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Association between retinal layer thickness and postoperative delirium in older patients
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作者 Zhongyong Shi Xin Ma +9 位作者 Tianyi Tang Meijuan Wang Hailin Zheng Yupeng Chen Jingxiao Hu Ariel Mueller Timothy T Houle Edward R Marcantonio Zhongcong Xie Yuan Shen 《General Psychiatry》 2025年第2期73-81,共9页
Background Postoperative delirium is one of the most common complications in the older surgical population,but its pathogenesis and biomarkers are largely undetermined.Retinal layer thickness has been demonstrated to ... Background Postoperative delirium is one of the most common complications in the older surgical population,but its pathogenesis and biomarkers are largely undetermined.Retinal layer thickness has been demonstrated to be associated with cognitive function in mild cognitive impairment and patients with Alzheimer’s disease.However,relatively little is known about possible retinal layer thickness among patients with postoperative delirium.Aims We aimed to investigate the relationship between retinal layer thickness and postoperative delirium in this cross-sectional study.Methods The participants(≥65 years old)having elective surgery under general anaesthesia were screened via medical records from Shanghai 10th People’s Hospital.Preoperative macular thickness and peripapillary retinal nerve fibre layer(RNFL)thickness were measured using optical coherence tomography(OCT).The Confusion Assessment Method(CAM)algorithm and CAM-Severity(CAM-S)were used to assess the incidence and severity of postoperative delirium on the first,second and third days after surgery.Results Among 169 participants(mean(standard deviation(SD)71.15(4.36)years),40(24%)developed postoperative delirium.Notably,individuals who developed postoperative delirium exhibited thicker preoperative macular thickness in the right eye compared with those who did not(mean(SD)283.35(27.97)µm vs 273.84(20.14)µm,p=0.013).Furthermore,the thicker preoperative macular thickness of the right eye was associated with a higher incidence of postoperative delirium(adjusted odds ratio 1.593,95%confidence interval(CI)1.093 to 2.322,p=0.015)and greater severity(adjusted mean difference(β)=0.256,95%CI 0.037 to 0.476,p=0.022)after adjustment for age,sex and Mini-Mental State Examination(MMSE)scores.However,such a difference or association did not appear in the left macular or bilateral peripapillary RNFL thicknesses.Conclusions Current findings demonstrated that preoperative macular thickness might serve as a potential non-invasive marker for the vulnerability of developing postoperative delirium in older surgical patients.Further large-scale validation studies should be performed to confirm these results. 展开更多
关键词 cognitive function retinal layer thickne layer thickness older patients retinal layer thickness mild cognitive impairment postoperative delirium
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Collaborative enhancement of thermal diffusivities and mechanical properties of C_(sf)-Cu/Mg composites via introducing Cu coating with different thicknesses 被引量:1
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作者 Yuan Ma Lingjun Guo +3 位作者 Jiancheng Wang Baolin Chen Lehua Qi Hejun Li 《Journal of Magnesium and Alloys》 2025年第1期229-242,共14页
Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excell... Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excellent mechanical properties,and heat dissipation.However,the different characteristics of C_(sf)and Mg alloy make the interface a critical issue affecting the synergistic improvement of thermal and mechanical properties of the composites.Here,Cu coating with different thicknesses is introduced to modify the C_(sf)/Mg interface,so as to simultaneously enhance the thermal and mechanical performances,which can combine the advantages of coating modification and matrix alloying.Results reveal that thermal diffusivity(TD)of 3-C_(sf)-Cu/Mg composites is as high as 22.12 mm^(2)/s and an enhancement of 52.97%is achieved compared with C_(sf)/Mg composites,as well as 16.3%enhancement of ultimate compressive strength(UCS)in the longitudinal direction,8.84%improvement of UCS in the transverse direction,and 53.08%increasement of ultimate tensile strength(UTS).Such improvement can be ascribed to the formation of intermetallic compounds.The formation of intermetallic compounds can not only effectively alleviate the lattice distortion of the matrix and decrease interfacial thermal resistance,but also bear the loads.Our work is of great significance for designing C_(sf)/Mg composites with integrated structure and function. 展开更多
关键词 Magnesium matrix composites Cu coating thickness Intermetallic compounds Thermal performances Mechanical properties
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Evolution of undeformed chip thickness and grinding forces in grinding of K4002 nickel-based superalloy using corundum abrasive wheels 被引量:1
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作者 Yang CAO Biao ZHAO +6 位作者 Wenfeng DING Xiaofeng JIA Bangfu WU Fei LIU Yanfang ZHU Qi LIU Dongdong XU 《Chinese Journal of Aeronautics》 2025年第1期131-146,共16页
The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusio... The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy. 展开更多
关键词 K4002 nickel-based superalloy Grinding force Material removal mechanism Undeformed chip thickness Quantity of active abrasive grains
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Numerical Simulation of the Pitting Corrosion Behavior of Stainless Steel Bellows Influenced by Varying Liquid Film Thicknesses
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作者 Lu-Jun Ren Guo-Min Li +2 位作者 Zhen-Xiao Zhu Hai-Yan Xiong Bing Li 《电化学(中英文)》 北大核心 2025年第7期37-51,共15页
To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations ... To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations to investigate the pitting corrosion rates and pit morphologies of bellows peaks and troughs under varying electrolyte film thicknesses.The model incorporates localized electrochemical reactions,oxygen concentration,and homogeneous solution reactions.For improved computational accuracy,the fitted polarization curve data were directly applied as nonlinear boundary conditions on the electrode surface via interpolation functions.Simulation results reveal that the peak regions exhibit faster corrosion rates than the trough regions.With increasing electrolyte film thickness(from 10μm to 500μm),corrosion rates at both peaks and troughs decrease progressively,and after 120 hours of simulation,the maximum corrosion rate at the peaks declines from 0.720 mm/a to 0.130 mm/a,and at the troughs from 0.520 mm/a to 0.120 mm/a,with the disparity in corrosion rates diminishing over time.Furthermore,as corrosion progresses,pits propagate deeper into the substrate,exhibiting both vertical penetration and lateral expansion along the passive film interface,ultimately breaching the substrate.This research offers valuable insights into designing corrosion mitigation strategies for stainless steel bellows in marine environments. 展开更多
关键词 Finite element method Pitting corrosion Stainless steel bellows Electrolyte film thickness
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Surgical site soft tissue thickness as a predictor of complications following arthroplasty
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作者 Kevin A Wu Faheem Pottayil +2 位作者 Crystal Jing Ankit Choudhury Albert T Anastasio 《World Journal of Methodology》 2025年第2期62-73,共12页
Appreciation of soft-tissue thickness(STT)at surgical sites is an increasingly recognized aspect of arthroplasty procedures as it may potentially impacting postoperative outcomes.Recent research has focused on the pre... Appreciation of soft-tissue thickness(STT)at surgical sites is an increasingly recognized aspect of arthroplasty procedures as it may potentially impacting postoperative outcomes.Recent research has focused on the predictive value of preoperative STT measurements for complications following various forms of arthroplasty,particularly infections,across procedures such as total knee,hip,shoulder,and ankle replacements.Several studies have indicated that increased STT is associated with a higher risk of complications,including infection and wound healing issues.The assessment of STT before surgery could play a crucial role in identifying patients at a higher risk of complications and may be instru-mental in guiding preoperative planning to optimize outcomes in arthroplasty procedures.Standardized measurement techniques and further research are essential to enhance the reliability and clinical utility of STT assessment for arthro-plasty surgery. 展开更多
关键词 Soft-tissue thickness ARTHROPLASTY Surgical complications Total knee arthroplasty Total hip arthroplasty Total shoulder arthroplasty Total ankle arthroplasty Preoperative assessment Wound healing Infection risk
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Petrogenesis of the Xuexiumaer Biotite Quartz Monzonite Porphyry in Southern Gangdese and its Implications for Paleo-Crustal Thickness of the Qinghai-Tibet Plateau
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作者 DAI Zuowen LI Guangming +3 位作者 LIU Hong HUANG Hanxiao FU Jiangang Jan Marten HUIZENGA 《Acta Geologica Sinica(English Edition)》 2025年第4期978-994,共17页
The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic a... The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic analyses on the Xuexiumaer biotite quartz monzonite porphyry(BQMP)sampled from the Lake Dajia area in southern Gangdese.This study aims to estimate the paleo-crustal thickness beneath this region during the early India-Asia collision stage using whole-rock Sr/Y and(La/Yb)N ratios as proxies.Results reveal that the Xuexiumaer BQMP was formed at~51 Ma in a collisional tectonic setting following Neo-Tethyan slab breakoff,and is an I-type granitoid derived primarily from partial melting of juvenile mafic lower crust with subordinate ancient crustal input.The estimated paleo-crustal thickness in the Lake Dajia area at~51 Ma is less than 40 km.This indicates that although the Qinghai-Tibet Plateau had already undergone significant crustal thickening and attained an exceptionally thick crust(>50 km)prior to the India-Asia collision as demonstrated by previous studies,some regions still maintained a crust only slightly thicker than the average continental crust(~35 km)at the initial collision stage.This limited crustal thickening likely resulted from underplating of subduction-related mafic magma at the mantle-crust boundary. 展开更多
关键词 paleo-crustal thickness PETROGENESIS Xuexiumaer GANGDESE Qinghai-Tibet Plateau
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Poor sleep and decreased cortical thickness in veterans with mild traumatic brain injury and post-traumatic stress disorder
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作者 Murray J.Andrews David H.Salat +2 位作者 William P.Milberg Regina E.McGlinchey Catherine B.Fortier 《Military Medical Research》 2025年第5期716-726,共11页
Background:Poor sleep quality has been associated with changes in brain volume among veterans,particularly those who have experienced mild traumatic brain injury(mTBI)and post-traumatic stress disorder(PTSD).This stud... Background:Poor sleep quality has been associated with changes in brain volume among veterans,particularly those who have experienced mild traumatic brain injury(mTBI)and post-traumatic stress disorder(PTSD).This study sought to investigate:1)whether poor sleep quality is associated with decreased cortical thickness in Iraq and Afghanistan war veterans,and 2)whether these associations differ topographically depending on the presence or absence of mTBI and PTSD.Methods:A sample of 440 post-9/11 era U.S.veterans enrolled in the Translational Research Center for Traumatic Brain Injury and Stress Disorders study at VA Boston,MA from 2010 to 2022 was included in the study.We examined the relationship between sleep quality,as measured by the Pittsburgh Sleep Quality Index(PSQI),and cortical thickness in veterans with mTBI(n=57),PTSD(n=110),comorbid mTBI and PTSD(n=129),and neither PTSD nor mTBI(n=144).To determine the topographical relationship between subjective sleep quality and cortical thickness in each diagnostic group,we employed a General Linear Model(GLM)at each vertex on the cortical mantle.The extent of topographical overlap between the resulting statistical maps was assessed using Dice coefficients.Results:There were no significant associations between PSQI and cortical thickness in the group without PTSD or mTBI(n=144)or in the PTSD-only group(n=110).In the mTBI-only group(n=57),lower sleep quality was significantly associated with reduced thickness bilaterally in frontal,cingulate,and precuneus regions,as well as in the right parietal and temporal regions(β=-0.0137,P<0.0005).In the comorbid mTBI and PTSD group(n=129),significant associations were observed bilaterally in frontal,precentral,and precuneus regions,in the left cingulate and the right parietal regions(β=-0.0094,P<0.0005).Interaction analysis revealed that there was a stronger relationship between poor sleep quality and decreased cortical thickness in individuals with mTBI(n=186)compared with those without mTBI(n=254)specifically in the frontal and cingulate regions(β=-0.0077,P<0.0005).Conclusions:This study demonstrates a significant relationship between poor sleep quality and lower cortical thickness primarily within frontal regions among individuals with both isolated mTBI or comorbid diagnoses of mTBI and PTSD.Thus,if directionality is established in longitudinal and interventional studies,it may be crucial to consider addressing sleep in the treatment of veterans who have sustained mTBI. 展开更多
关键词 TRAUMA Brain injury SLEEP VETERANS Cortical thickness
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Unraveling thickness-dependent lithiation behaviors of boride films for all-solid-state thin-film lithium batteries
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作者 Jie Lin Wenbin Wu +4 位作者 Jie Zhu Qing Luo Laisen Wang C.Buddie Mullins Dong-Liang Peng 《Energy Materials and Devices》 2025年第2期23-32,22,共11页
The energy density of thin-film lithium batteries(TFLBs)is predominantly determined by the average voltage and specific capacity,however,the mechanism of regulating the voltage plateaus of the film electrodes is not w... The energy density of thin-film lithium batteries(TFLBs)is predominantly determined by the average voltage and specific capacity,however,the mechanism of regulating the voltage plateaus of the film electrodes is not well understood.In this study,three boride films(Co–B,Fe–B,and Co–Fe–B alloys)with different thick-nesses were fabricated to enhance the specific capacity and voltage stability of TFLBs.By analyzing the cycling performance,redox peak evolution,and capacitive contribution,the thickness-dependent lithiation behavior of the thin/thick films was elucidated.Theoretical simulations and electrochemical analysis were conducted to investigate how the lithiation behaviors affected the voltage profiles of the film electrodes.In addition,the various-thickness CoB films were compared in all-solid-state TFLBs,demonstrating the universality and practicability of this simple regulation strategy to develop high-performance energy storage devices. 展开更多
关键词 thickness voltage plateau cycling stability BORIDE thin-film lithium battery
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Experimental determination of stripping foil thickness on the XiPAF synchrotron
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作者 Xiao-Yu Liu Hong-Juan Yao +4 位作者 Shu-Xin Zheng Ze-Jiang Wang Yang Xiong Pei-Zhi Fang Zhong-Ming Wang 《Nuclear Science and Techniques》 2025年第3期27-37,共11页
Stripping injection overcomes the limitations of Liouville's theorem and is widely used for beam injection and accumulation in high-intensity synchrotrons.The interaction between the stripping foil and beam is cru... Stripping injection overcomes the limitations of Liouville's theorem and is widely used for beam injection and accumulation in high-intensity synchrotrons.The interaction between the stripping foil and beam is crucial in the study of stripping injection,particularly in low-energy stripping injection synchrotrons,such as the XiPAF synchrotron.The foil thickness is the main parameter that affects the properties of the beam after injection.The thin stripping foil is reinforced with collodion during its installation.However,the collodion on the foil surface makes it difficult to determine its equivalent thickness,because the mechanical measurements are not sufficiently reliable or convenient for continuously determining foil thickness.We propose an online stripping foil thickness measurement method based on the ionization energy loss effect,which is suitable for any foil thickness and does not require additional equipment.Experimental studies were conducted using the XiPAF synchrotron.The limitation of this method was examined,and the results were verified by comparing the experimentally obtained beam current accumulation curves with the simulation results.This confirms the accuracy and reliability of the proposed method for measuring the stripping foil thickness. 展开更多
关键词 Stripping injection Foil thickness SYNCHROTRON Injection efficiency Experimental study
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Film thickness effect on 2D lead-free hybrid double perovskite properties: Band gap, photocurrent and stability
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作者 Mohamed Saber Lassoued Faizan Ahmad Yanzhen Zheng 《Chinese Chemical Letters》 2025年第4期449-454,共6页
Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic pr... Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic properties has not yet been investigated. Herein, we synthesized two new Ruddlesden–Popper LFHDPs, namely(C_(5)H_(12)N)_(4)AgBiI_(8)(CAB-1) and(C_(6)H_(14)N)_(4)Ag Bi I8(CAB-2) using cyclopentylamine and cyclohexylamine as monoamine ligands. Indeed, these two Ag(Ⅰ)-Bi(Ⅲ) LFHDPs form smooth and uniform films ranging in thickness from 250 nm to 1 μm, with preferred orientations. Notably, the studies on the optical properties showed that the direct band gap value decreased from 2.17 e V to 1.91 e V for CAB-1 and from 2.05 e V to 1.86 e V for CAB-2 with increasing thickness. Accordingly, photo-current response using a xenon lamp revealed a significant difference of over 1000 n A between light and dark conditions for1 μm-thickness films, suggesting potential for light harvesting. Other than that, thicker films of CAB-1and CAB-2 exhibit high stability for 90 days in a relatively humid environment(RH of 55%), paving the way for promising optoelectronic applications. 展开更多
关键词 LEAD-FREE Double perovskites Film thickness Photocurrent response High stability
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Use of Prenasal Thickness,Nasal Bone Length and Their Ratio in Diagnosing Down Syndrome at 16-25 weeks'of gestation in India:A Retrospective,Observational,Case Control Study
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作者 Mhaske Nilesh Madhukar Rachna Gupta +2 位作者 Akshatha Sharma Smriti Prasad Anita Kaul 《iRADIOLOGY》 2025年第3期239-247,共9页
Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with t... Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with trisomy 21(T 21)between 16 and 25 weeks of gestation as a diagnostic tool for T 21.Methods:Facial profile images in the two dimensional(2D)gray scale were assessed to measure fetal NBL and PNT between 16 and 25 weeks of gestation.The PNT:NBL ratio of the fetuses was calculated.Nomograms were constructed from the data of morphologically normal fetuses at live birth.The PNT,NBL,and PNT:NBL ratio of fetuses with confirmed T 21(n=31)and morphologically normal fetuses at live birth(controls,n=3485)were compared.Results:Nomograms for PNT,NBL,and the PNT:NBL ratio were constructed.In T 21 fetuses,PNT(>95th percentile),NBL(<5th percentile),and the PNT:NBL ratio(>95th percentile)showed a sensitivity of 25%,29%,and 45%for PNT,NBL,and PNT:NBL,respectively,and specificity of 95%,96%,and 94%,for PNT,NBL,and PNT:NBL,respectively.All of these markers showed a negative predictive value of 99%.Conclusion:PNT,NBL,and the PNT:NBL ratio have high diagnostic value for fetuses with Down syndrome and can be incorporated easily in the current second trimester screening protocol for T 21.PNT,NBL,and the PNT:NBL ratio are more specific markers for Down syndrome than those used in previous studies. 展开更多
关键词 down syndrome nasal bone length pernasal thickness prenatal screening soft marker
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Theoretical and Experimental Investigations on Thickness Uniformity in Double-sided Lapping
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作者 Zhuolin Cai Zhe Yang +4 位作者 Bo Pan Jiale Lian Lianlin Wang Sergei Pronkevich Jiang Guo 《Chinese Journal of Mechanical Engineering》 2025年第3期151-163,共13页
The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has ex... The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has explored the thickness uniformity among different workpieces after double-sided lapping,and the underlying mechanism remains unclear.To address the demand for higher precision,this paper first analyzed the relative kinematic model between the workpiece and the lapping plate to clarify the causes of thickness variations among workpieces after double-sided lapping.Subsequently,a finite element method(FEM)model was developed to account for the pressure distribution on the workpiece surfaces at the initial stage of the process.The results indicate that the number of workpieces influences the final thickness variation.Then,various sets of thin copper plates with different thicknesses were lapped,and the findings revealed that five copper plates processed simultaneously exhibited more uniform thickness compared to the three plates.The experimental results align well with the theoretical analysis.Ultimately,a thickness variation of less than 6μm was achieved on five copper plates measuringΦ100×2.9 mm.This study presents a comprehensive analysis of the mechanisms influencing thickness uniformity in the double-sided lapping process and provides practical guidelines for optimizing the process to achieve stringent precision standards in industrial applications. 展开更多
关键词 Double-sided lapping thickness uniformity Theoretical analysis FEM Thin copper plate
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A Dynamic Prediction Approach for Wire Icing Thickness under Extreme Weather Conditions Based on WGAN-GP-RTabNet
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作者 Mingguan Zhao Xinsheng Dong +5 位作者 Yang Yang Meng Li Hongxia Wang Shuyang Ma Rui Zhu Xiaojing Zhu 《Computer Modeling in Engineering & Sciences》 2025年第2期2091-2109,共19页
Ice cover on transmission lines is a significant issue that affects the safe operation of the power system.Accurate calculation of the thickness of wire icing can effectively prevent economic losses caused by ice disa... Ice cover on transmission lines is a significant issue that affects the safe operation of the power system.Accurate calculation of the thickness of wire icing can effectively prevent economic losses caused by ice disasters and reduce the impact of power outages on residents.However,under extreme weather conditions,strong instantaneous wind can cause tension sensors to fail,resulting in significant errors in the calculation of icing thickness in traditional mechanics-based models.In this paper,we propose a dynamic prediction model of wire icing thickness that can adapt to extreme weather environments.The model expands scarce raw data by the Wasserstein Generative Adversarial Network with Gradient Penalty(WGAN-GP)technique,records historical environmental information by a recurrent neural network,and evaluates the ice warning levels by a classifier.At each time point,the model diagnoses whether the current sensor failure is due to icing or strong winds.If it is determined that the wire is covered with ice,the icing thickness will be calculated after the wind-induced tension is removed from the ice-wind coupling tension.Our new model was evaluated using data from the power grid in an area with extreme weather.The results show that the proposed model has significant improvements in accuracy compared with traditional models. 展开更多
关键词 Wire icing thickness instantaneous wind transmission lines WGAN-GP-RTabNet dynamic tension
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The Effect of Carrier Doping and Thickness on the Electronic Structures of La_(3)Ni_(2)O_(7)Thin Films
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作者 Haoliang Shi Zihao Huo +4 位作者 Guanlin Li Hao Ma Tian Cui Daoxin Yao Defang Duan 《Chinese Physics Letters》 2025年第8期201-229,共29页
The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the re... The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the realization of superconductivity in compressively strained La_(3)Ni_(2)O_(7)thin films grown on the SrLaAlO_(4)substrates,with a T_(c)exceeding 40 K,represents a significant step toward this goal.Here,we investigate the influence of film thickness and carrier doping on the electronic structure of La_(3)Ni_(2)O_(7)thin films,ranging from 0.5 to 3 unit cells,using first-principles calculations.For a 2 unit-cell film with an optimal doping concentration of 0.3 hole per formula unit(0.15 hole/Ni),the Ni-d_(z^(2))interlayer bonding state crosses the Fermi level,resulting in the formation ofγpockets at the Fermi surface.These findings align with angle-resolved photoemission spectroscopy experimental data.Our results provide theoretical validation for the recent experimental discovery of ambient-pressure superconductivity in La_(3)Ni_(2)O_(7)thin films and underscore the significant impact of film thickness and carrier doping on electronic property modulation. 展开更多
关键词 bilayer nickelate film thickness electronic structure l electronic structure la ni o thin films carrier doping stabilize superconductivity SUPERCONDUCTIVITY
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Implantation of a posterior chamber phakic intraocular lens on Bruch’s membrane opening-minimum rim width,retinal nerve fiber layer,and macular thickness
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作者 Josefina Reñones Humberto Carreras +4 位作者 Alfonso Antón-López Ángel García-García Rafael Melián Juan Francisco Loro-Ferrer David P Piñero 《International Journal of Ophthalmology(English edition)》 2025年第9期1658-1664,共7页
AIM:To assess whether the implantation of a posterior chamber phakic intraocular lens produces changes in optical coherence tomography(OCT)measurements of macular thickness(MT)and two parameters that define the struct... AIM:To assess whether the implantation of a posterior chamber phakic intraocular lens produces changes in optical coherence tomography(OCT)measurements of macular thickness(MT)and two parameters that define the structure of the optic nerve,the peripapillary nerve fiber layer(RNFL)and the Bruch’s membrane opening-minimum rim width(BMO-MRW).METHODS:This nonrandomized prospective pre-post study included 86 eyes of 48 patients(age,20-47y;axial length:23.10-28.95 mm)scheduled for myopia or myopic astigmatism correction with implantation of the implantable collamer lens(ICL).Eyes with glaucoma or any other ocular disease that could alter OCT results were excluded.RNFL,BMO-MRW and MT were measured preoperatively,and at 1 and 6mo after surgery using spectral-domain OCT.Changes between preoperative and postoperative values were evaluated.RESULTS:There was a significant increase in BMOMRW at 1mo(mean change:3.48±15.07μm,P=0.041).No significant changes were found during the rest of followup(1-6mo postop.,P=0.623).There was also a significant increase in RNFL thickness at 1mo af ter surger y(1.45±2.18μm,P<0.001),but with a significant reduction from 1 to 6mo postoperatively(P=0.002).Regarding MT,it increased significantly at 1mo(2.46±3.76μm,P<0.001),with a significant decrease afterwards(P=0.048).Measurements of the three parameters at 6mo were slightly superior to preoperative values(P<0.01).CONCLUSION:Minimal changes are induced in BMOMRW,RNFL and MT after ICL implantation in healthy eyes,confirming the safety of the surgical procedure regarding the structure of the optic nerve head and the macula,and indicating that this phakic intraocular lens seems to have a slight impact on OCT measurements. 展开更多
关键词 implantable collamer lens phakic intraocular lens posterior chamber macular thickness macular edema optical coherence tomography
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Change in choroid thickness and vascularity index associated with accommodation and aberration after small-incision lenticule extraction
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作者 Dan Cheng Yi-Lin Qiao +6 位作者 Xue-Ying Zhu Kai-Ming Ruan Heng-Li Lian Mei-Xiao Shen Shu-Lin Wang Li-Jun Shen Yu-Feng Ye 《International Journal of Ophthalmology(English edition)》 2025年第4期672-682,共11页
AIM:To explore choroidal thickness(CT)and choroidal vascularity index(CVI)changes around the macula and optic nerve head(ONH)using swept-source optical coherence tomography(SS-OCT)after small-incision lenticule extrac... AIM:To explore choroidal thickness(CT)and choroidal vascularity index(CVI)changes around the macula and optic nerve head(ONH)using swept-source optical coherence tomography(SS-OCT)after small-incision lenticule extraction(SMILE)and evaluate their associations with accommodation and aberrations.METHODS:Participants were divided into more myopic group(43 eyes)and less myopic group(33 eyes)according to refractive error.SS-OCT,negative relative accommodation(NRA),and positive relative accommodation(PRA)were analyzed before and 1d,1wk,and 1mo postoperatively.Root mean square higher-order aberrations(RMS HOAs),spherical aberrations(SAs),and coma were compared preoperative,1wk,and 1mo postoperatively.RESULTS:After surgery,RMS(0.29±0.26)and Coma(0.16±0.19)all increased.In the more myopic group,central and T macular CT(247.58±63.81 a n d 276.45±62.52μm)increased.NRA(0.41±0.51)and PRA(0.10±1.30)decreased,and SAs(0.21±0.21)increased.In the less myopic group,all regional and mean macular CT increased.NRA was correlated with mean and inferior CTs and mean ONH CVI.SE was correlated with macular CT,CVI,and ONH CT.Mean macular and ONH CTs were associated with RMS HOA,SA,and coma.Macular T2 CT was a significant predictor of SA.Macular T2 and N1 CT were correlated with coma.CONCLUSION:More variations in accommodation and aberrations and fewer choroid thickens on macular and ONH are found in more myopic eyes after SMILE.Choroidal values are associated with accommodation and aberrations during SMILE.Choroid parameters on SS-OCT varies in eyes with different refractive errors after SMILE and has an association with accommodation and visual quality. 展开更多
关键词 swept-source optical coherence tomography small-incision lenticule extraction choroid thickness ACCOMMODATION ABERRATION
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Impact of quadratic thermal radiation on MHD nanofluid flow across a stretching sheet with variable thickness:Xue and Yamado-Ota thermophysical model
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作者 Kandavkovi Mallikarjuna Nihaal Ulavathi Shettar Mahabaleshwar +1 位作者 Dia Zeidan Sang Woo Joo 《Acta Mechanica Sinica》 2025年第6期16-24,共9页
The work comparing the Yamada-Ota and Xue models for nanoparticle flow across a stretching surface has benefits in nanotechnology,medicinal treatments,environmental engineering,renewable energy,and heat exchangers.Mos... The work comparing the Yamada-Ota and Xue models for nanoparticle flow across a stretching surface has benefits in nanotechnology,medicinal treatments,environmental engineering,renewable energy,and heat exchangers.Most published nanofluid flow models assumed constant thermal conductivity and viscosity.With such great physiognomies in mind,the novelty of this work focuses on comparing the performance of the nanofluid models,Xue,and Yamada-Ota models on a stretched sheet with variable thickness under the influence of a magnetic field and quadratic thermal radiation.The altered boundary layer equations for momentum and temperature,subject to adequate boundary conditions,are numerically solved using an optimized,efficient,and extensive bvp-4c approach.The effects of non-dimensional constraints such as magnetic field,power index of velocity,wall thickness parameter,and quadratic radiation parameter on momentum and temperature profile in the boundary layer area are analyzed thoroughly and outcomes were illustrated graphically.Additionally,the consequences of certain distinctive parameters over engineering factors are also examined and results were presented in tabular form.From the outcomes,it is seen that fluid velocity slows down in the presence of a magnetic field but the opposite nature is observed in the case of temperature profile.With a higher index of velocity,the velocity profile decreases and the temperature field elevates.It has been found that the presence of quadratic convection improves the temperature field.The outcomes of the two models are compared.The Yamada-Ota model performed far better than the Xue model in the heat transfer analysis. 展开更多
关键词 Green nanofluid MHD Quadratic thermal radiation Xue and Yamada-Ota model Variable thickness
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Morphological alterations of macular region in fellow eyes of patients with idiopathic full-thickness macular holes detected by optical coherence tomography
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作者 Yan-Ting Li Xin-Zhu Chen +5 位作者 Yun-Feng Lu Yue-Qi Liu Tian-Hong Wu Zi-Yue Song Zheng-Gao Xie Pei-Rong Lu 《International Journal of Ophthalmology(English edition)》 2025年第4期642-647,共6页
AIM:To describe the optical coherence tomography(OCT)features in the fellow eyes of individuals with full-thickness macular holes(FTMHs).METHODS:This multicenter retrospective study included observational and validati... AIM:To describe the optical coherence tomography(OCT)features in the fellow eyes of individuals with full-thickness macular holes(FTMHs).METHODS:This multicenter retrospective study included observational and validation groups,incorporating fellow eyes of patients diagnosed with idiopathic FTMH.OCT images were categorized according to International Vitreomacular Traction Study(IVTS)and Gass classification.Age-and sex-related cataract patients were served as control groups.Vertical and horizontal OCT images were chosen for further measurement.OCT parameters including foveal floor width(FFW),central foveal thickness(CFT)and FFW/CFT ratio were assessed and compared between observational and control groups and were validated by validation group.Receiver operating characteristic(ROC)curves were plotted for OCT parameters in identifying macular holes(MHs).RESULTS:A total of 73 patients were included in the observational group,comprising 51 females and 22 males,with an average age of 65.5±7.3y and an axial length of 23.9±0.8 mm.The validated group consisted of 47 patients,including 31 females and 16 males,with an average age of 65.0±7.4y and an average axial length of 23.6±0.8 mm.In the observational group,16.4%of the fellow eyes associated with FTMHs also exhibited MHs,while in the validated group,this prevalence was 12.7%.The 45.2%in the observational group and 44.6%in validated group of these fellow eyes displayed abnormalities including vitreomacular adhesion(VMA),vitreomacular traction(VMT),and MHs.Statistically significant differences were observed in FFW,CFT,and FFW/CFT ratio between control and observational group,as well as validated group(P<0.01),no matter in the vertical or horizontal layer.ROC curves revealed the area under the curve(AUC)for FFW and the FFW/CFT ratio was 0.85 and 0.90,respectively.CONCLUSION:In the case of unilateral idiopathic MHs,it was important to carefully monitor the condition of the fellow eye.The FFW and FFW/CFT ratio may be good metrics for predicting MHs. 展开更多
关键词 optical coherence tomography macular hole FOVEA foveal floor width central foveal thickness
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Influence mechanism and calculation of the minimum safe thickness of waterproof rock mass in karst tunnels
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作者 AN Pengtao LI Maoxiang +1 位作者 ZHANG Wenjun LIU Xiong 《Journal of Mountain Science》 2025年第2期695-709,共15页
Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the ... Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the minimum safe thickness of water-proof rock mass,a simplified calculation model of water-proof rock mass thickness when the karst cave is located at any location around the tunnel is established,and the influence of multiple factors on the overall stability of water-proof rock mass is considered.Based on the cusp catastrophe theory,the analytical expressions for the safety thickness of waterproof rock mass are derived.Based on the finite difference principle,the analytical expressions of the safety thickness of water-proof rock mass are verified.In order to improve the application range of the analytical formula derived in this paper,the analytical formula is optimized based on the instability principle differences between the simplified calculation model and the elastic compressive bar.The research results show that the necessary condition solution is more applicable and much safer than the sufficient condition solution.Tectonic stress,rock beam length and karst cave water pressure are significantly positively correlated with the safe thickness of the waterproof rock mass.The calculated results of the semioptimized formula and the unoptimized formula are constant values,independent of the karst cave location.While the calculated results of the fully optimized formula are variable values,correlated with the karst cave location,the thickness of the waterproof rock mass gradually decreases as the karst cave location moves from the top of the tunnel to the bottom of the tunnel.The unoptimized formula does not consider the influence of the lateral force of the rock beam,and is not suitable for the working condition with large lateral force,the calculation results of the semi-optimized formula and the fully optimized formula are not very different and are biased to safety,so it can be given priority. 展开更多
关键词 Tunnel engineering Water inrush disaster Safe thickness Waterproof rock mass Concealed karst cave
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Prediction of overburden layer thickness based on spatial heterogeneity analysis and machine learning models in hillslope regions
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作者 Zhilu Chang Shui-Hua Jiang +4 位作者 Faming Huang Lei Shi Jinsong Huang Jianhong Wan Filippo Catani 《Geoscience Frontiers》 2025年第5期109-122,共14页
The spatial distribution of overburden layer thickness(OLT)is crucial for landslide susceptibility prediction and slope stability analysis.Due to OLT spatial heterogeneity in hillslope regions,combined with the diffic... The spatial distribution of overburden layer thickness(OLT)is crucial for landslide susceptibility prediction and slope stability analysis.Due to OLT spatial heterogeneity in hillslope regions,combined with the difficulty and time consumption of OLT sample collection,accurately predicting OLT distribution remains a challenging.To address this,a novel framework has been developed.First,OLT samples are collected through field surveys,remote sensing,and geological drilling.Next,the heterogeneity of OLT’s spatial distribution is analyzed using the probability distribution of OLT samples and their horizontal and vertical distributions.The OLT samples are categorized and the small sample categories are expanded using the synthetic minority over-sampling technique(SMOTE).The slope position is selected as a key conditioning factor.Subsequently,16 conditioning factors are applied to construct OLT prediction model using the random forest regression algorithm.Weights are assigned to each OLT sample category to balance the uneven distribution of sample sizes.Finally,the Pearson correlation coefficient,mean absolute error(MAE),root mean square error(RMSE),and Lin’s concordance correlation coefficient(Lin’s CCC)are employed to validate the OLT prediction results.The Huangtan town serves as the case study.Results show:(1)heterogeneity analysis,SMOTE-based OLT sample expansion strategy and slope position selection can significantly mitigate the effect of spatial heterogeneity on OLT prediction.(2)The Pearson correlation coefficient,RMSE,MAE and Lin’s CCC values are 0.84,1.173,1.378 and 0.804,respectively,indicating excellent prediction performance.This research provides an effective solution for predicting OLT distribution in hillslope regions. 展开更多
关键词 Overburden layer thickness Heterogeneity analysis Random forest regression Slope position Hillslope regions
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