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Retinal layers thickness and retinal vascular parameters in patients with multiple sclerosis
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作者 Mehdi Moghaddasi Mahsa Sardarinia +3 位作者 Mostafa Soltansanjari Ahmad Vafajoo Nafise Mohebi Simin Zare 《国际眼科杂志》 2026年第3期368-374,共7页
AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patie... AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patients diagnosed with MS and a control group of 43 healthy hospital staff matched in terms of age and sex at Iran University,department of neurology and ophthalmology from March 2020 to March 2021.The ophthalmic parameters of each patient were recorded,and optical coherence tomography was used to evaluate the retinal thickness in the layers.RESULTS:This study enrolled a total of 85 participants,with a mean age of 40.44±11.52 years,including 61 females(72%).The control group consisted of 43 individuals with a mean age of 39.49±11.07 years,while the MS group comprised 42 participants with a mean age of 41.40±12.01 years.The mean disease duration in the MS group was 8.45±6.04 a.The thickness of the ganglion cell layer in the right eye was significantly lower in the MS group compared to the control group(P=0.034).In addition,except for the left nasal sector(P=0.106),the mean peripapillary neurofibrillation in all examined sectors were significantly lower in the MS group than in the control group(P<0.05).The average vessel density in both the deep and superficial capillary plexuses across all regions of both eyes was lower in the MS group than in the control group,with all comparisons for the superficial capillary plexus showing statistical significance(P<0.05 for all except the left nasal sector).CONCLUSION:The thickness of the retina of patients with MS is significantly reduced.Therefore,optical coherence tomography results can be used as a reliable tool to evaluate disease progression and prognosis in MS patients. 展开更多
关键词 multiple sclerosis optical coherence tomography RETINA retinal vascular disorder retinal layer thickness
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Enhancing Solar Photovoltaic Efficiency:A Computational Fluid Dynamics Analysis 被引量:1
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作者 Rahool Rai Fareed Hussain Mangi +1 位作者 Kashif Ahmed Sudhakar Kumaramsay 《Energy Engineering》 EI 2025年第1期153-166,共14页
The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable energy.Solar ener... The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable energy.Solar energy,among the various renewable sources,is particularly appealing due to its abundant availability.However,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight hours.This study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat transfer.The CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of 10.These specific parameters were found to maximize the heat transfer and temperature reduction efficiency.This finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar panels.Alternative cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits. 展开更多
关键词 PV module efficiency water film thickness reynolds number CFD analysis PV/T renewable energy
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Film thickness effect on 2D lead-free hybrid double perovskite properties: Band gap, photocurrent and stability 被引量:2
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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 被引量:1
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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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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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Influence mechanism and calculation of the minimum safe thickness of waterproof rock mass in karst tunnels 被引量:1
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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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Crustal Thickness Evolution Controls the Formation of Porphyry Cu Deposits in Collisional Orogens:An Example from Central Tethys 被引量:1
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作者 WANG Xuhui LANG Xinghai +2 位作者 WU Changyi DENG Yulin Robert MORITZ 《Acta Geologica Sinica(English Edition)》 2025年第2期522-531,共10页
The key factor that controls the genesis of porphyry Cu deposits(PCDs)in collisional orogens remains a debated topic.This study employs whole-rock La/Yb proxies to quantitatively constrain the spatial and temporal var... The key factor that controls the genesis of porphyry Cu deposits(PCDs)in collisional orogens remains a debated topic.This study employs whole-rock La/Yb proxies to quantitatively constrain the spatial and temporal variations in crustal thickness of the South Armenian-Iranian magmatic belt(SAIMB)within the Zagros orogen(central Tethys region)since the Eocene.Our results show that rapid crustal thickening occurred first in the NW section of the SAIMB at~35 Ma,then propagated southeastward into the central and SE sections at~25 Ma and 20 Ma,respectively,indicating that the Arabia-Eurasia collision was diachronous.The formation of the large and giant collision-related PCDs in the SAIMB might have been controlled by the collision process because they developed first in the NW section of the SAIMB and subsequently propagated southeastward into the central and SE sections.More importantly,crustal thickness mapping shows that the PCDs are preferentially developed in the thickened crust areas(>50 km).Our findings propose that thickened crust is critical for the formation of the PCDs in collisional orogens by promoting Fe^(2+)-rich minerals as a fractionating phase,driving magmatic auto-oxidation and releasing Cu into the magmas.The Cu is then partitioned into magmatic fluids,sustaining the porphyry systems.Furthermore,our research highlights that the thickened crust hosting PCDs was characterized by a previously thinner crust(<40 km),where magmas had low oxygen fugacity due to the absence of the auto-oxidation process.Consequently,chalcophile elements(e.g.,Cu)efficiently separated from the melt through sulfide segregation,forming large Cu-bearing lower-crustal cumulates.These cumulates can be mobilized with an increase in oxygen fugacity,incorporating into subsequent porphyry mineralization.We thus propose that the crustal thickness evolution over time controls the formation of the PCDs in collisional orogens.There are two essential stages in the collision-related PCDs formation:the first is high-flux magmatism in the thin crustal setting(<40 km),leading to metal-fertilized lower crust through sulfide segregation,and the second is the intracrustal auto-oxidation during crustal thickening(>50 km)which facilitates pre-enriched sulfides in the lower crust to re-dissolve,releasing Cu into the magmas. 展开更多
关键词 porphyry Cu deposit crustal thickness pre-enrichment Arabia–Eurasia collision Tethyan metallogenic belt
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Melatonin improves endometrial receptivity and embryo implantation via MT2/PI3K/LIF signaling pathway in sows 被引量:1
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作者 Xue Qin Menghao Yang +4 位作者 Yang Yu Xiaolin Wang Yi Zheng Rui Cai Weijun Pang 《Journal of Animal Science and Biotechnology》 2025年第2期631-652,共22页
Background Increased backfat thickness of sows in early gestation is negative to reproductive performance.Endometrial receptivity is an important determinant of reproductive success,but it is unclear whether the effec... Background Increased backfat thickness of sows in early gestation is negative to reproductive performance.Endometrial receptivity is an important determinant of reproductive success,but it is unclear whether the effect of sow backfat thickness on litter size is associated with endometrial receptivity and whether melatonin treatment may have benefits.The present study seeks to answer these questions through in vitro and in vivo investigations.Results Excessive lipid deposition and lower melatonin levels in the uterus are detrimental to endometrial receptivity and embryo implantation in high backfat thickness sows.In cells treated with melatonin,the MT2/PI3K/LIF axis played a role in reducing lipid accumulation in porcine endometrial epithelium cells and improved endometrial receptivity.Furthermore,we found a reduction of lipids in the uterus after eight weeks of intraperitoneal administration of melatonin to HFD mice.Notably,melatonin treatment caused a significant reduction in the deposition of endometrial collagen,an increase in the number of glands,and repair of the pinopode structure,ultimately improving endometrial receptivity,promoting embryo implantation,and increasing the number of litter size of mice.Conclusions Collectively,the finding reveals the harmful effects of high backfat thickness sows on embryo implantation and highlight the role of melatonin and the MT2/PI3K/LIF axis in improving endometrial receptivity by enhancing metabolism and reducing the levels of uterine lipids in obese animals. 展开更多
关键词 Backfat thickness Embryo implantation Endometrial receptivity MELATONIN MT2/PI3K/LIF SOW
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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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Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber
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作者 Honghan Wang Xinyu Xiao +5 位作者 Shangru Zhai Chuang Xue Guangping Zheng Deqing Zhang Renchao Che Junye Cheng 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期424-438,共15页
The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engin... The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter). 展开更多
关键词 High-entropy alloys Carbothermal shock Switchable electron migration modes Emblematic shell-core heterointerfaces Ultra-thin thickness
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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study
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作者 Kaixuan Zhou Gaoxiong Duan +19 位作者 Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong Yang Demao Deng 《Neural Regeneration Research》 SCIE CAS 2025年第10期3013-3024,共12页
Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal b... Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase data.As a result,little is known about the pathophysiology of sleep disturbances in the acute phase of COVID-19.To address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this study.Eleven COVID-19 patients with sleep disturbances were included in a longitudinal analysis.We found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain lobes.The cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index scores.Additionally,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy controls.The 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep disturbances.Our findings indicate that the sleep disturbances patients had altered morphology in the cortical and hippocampal structures during the acute phase of infection and persistent changes in cortical regions at 3 months post-infection.These data improve our understanding of the pathophysiology of sleep disturbances caused by COVID-19. 展开更多
关键词 brain structure cortical gray matter volume cortical surface area cortical thickness HIPPOCAMPUS magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume
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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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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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Real-world topographical efficacy, procedural outcome and safety of endoscopic full thickness resection in colon segments
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作者 Heinz Albrecht Claus Schaefer +3 位作者 Andreas Stegmaier Juergen Gschossmann Alexander Hagel Martin Raithel 《World Journal of Gastrointestinal Endoscopy》 2025年第10期155-164,共10页
BACKGROUND Despite growing evidence on endoscopic full thickness resection(EFTR),data on segment-specific outcomes in real-world patients remain limited.AIM To investigate segment-specific outcomes of EFTR using a ful... BACKGROUND Despite growing evidence on endoscopic full thickness resection(EFTR),data on segment-specific outcomes in real-world patients remain limited.AIM To investigate segment-specific outcomes of EFTR using a full-thickness resection device(FTRD)for neoplastic colorectal lesions.METHODS In this multicenter,retrospective study,EFTR was conducted in unselected realworld patients referred to participating German centers after colonoscopy confirmed EFTR eligibility.The primary outcome was histologically complete resection(R0)of the lesion,including segment-specific outcomes and adverse events(AE).Additional efficacy and safety parameters were investigated by colonic topography for up to 30 days.RESULTS The analysis included 102 patients(64 males,38 females)with a median age of 70 years.EFTR via FTRD was technically successful in all patients.The R0 rate was 81.4%,segment-specifically ranging from 85.0%(rectum),84.6%(descending colon),84.0%(ascending colon),83.3%(cecum),and 76.5%(sigmoid colon)to 73.3%(transverse colon).Examination time was longer in proximal parts compared to the rectosigmoid(non-significant).Overall,33 patients(32.4%)experienced AE,including only one major complication(0.98%;perforation of sigmoid colon).Abdominal postsurgical pain(18.6%),hematochezia(9.8%),and hemoglobin decline(7.8%)were the most frequent minor complications.Transverse colon lesions had the numerically highest rate of AE,with 8 of 15 patients(53.3%)affected.CONCLUSION EFTR is efficacious for neoplastic colorectal lesions,though R0 rates vary by location.This may impact patient education,selection of the operator,and consideration of laparoscopy surgery. 展开更多
关键词 Endoscopic full thickness resection Full thickness resection device Colorectal neoplasms Colorectal topography Endoscopy Endoscopic mucosal resection
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Beyond bark thickness:multifunctional explanations for variations in relative bark allocation in temperate forest trees
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作者 Huabin Zhao Zhecheng Liu +5 位作者 Yichen Duan Yongjie Han Luna Zhang Xue Sun Chuankuan Wang Xingchang Wang 《Journal of Forestry Research》 2025年第6期175-186,共12页
While the fire protection function of tree bark has been extensively documented,other critical functions,including storage and mechanical support,have received less attention.In this study we examined:(1)the allometry... While the fire protection function of tree bark has been extensively documented,other critical functions,including storage and mechanical support,have received less attention.In this study we examined:(1)the allometry of bark thickness(and biomass)against wood radius(and biomass)at a disc level,(2)differences in bark allocation between the ratio and the regression approaches,(3)differences between bark thickness and biomass as metrics of bark allocation,and(4)how bark allocation is associated with the evolution of wood from non-porous to diffuse-porous and ring-porous types.Thickness and biomass of bark and wood were measured using trunk discs of 88 individual trees of 36 species in a temperate forest characterized by a long fire interval.Allometric relationships of bark thickness(and biomass)against wood radius(and biomass)explained why both relative bark thickness and biomass decreased with increasing stem diameter.Variations in both among species varied by factors of 3.5 to 7.5 depending on the measurement methods.The ratio approach produced higher estimates of both relative bark thickness and biomass compared to the regression approach,while relative bark thickness was significantly lower than relative bark biomass.Ring-porous species exhibited higher bark thickness based on the ratio approach,which might reflect evolutionary adaptations where ring-porous species have developed thicker bark as protection:thermal insulation against freeze-thaw embolism coupled with carbohydrate reservoirs for hydraulic repair.The regression slope of bark allocation against wood density increased along the wood porosity gradient,demonstrating evolutionary biomechanical coordination between bark and wood.These findings highlight systematic coupling between bark and xylem multifunctionality. 展开更多
关键词 Bark thickness Stem diameter Relative bark thickness Relative bark biomass Bark allocation
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Layer-by-layer tear film measurement in patients with dry eye and meibomian gland dysfunction
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作者 Reiko Arita Gaku Takeuchi +2 位作者 Kiyofumi Sasai Masatsugu Nakamura Masahiro Akiba 《International Journal of Ophthalmology(English edition)》 2025年第11期2057-2064,共8页
AIM:To evaluate parameters measured using the tear film imager(TFI)prototype,a new technology that enables to quantify the tear film thickness of lipid and mucoaqueous layers.METHODS:In this cross-sectional study,pati... AIM:To evaluate parameters measured using the tear film imager(TFI)prototype,a new technology that enables to quantify the tear film thickness of lipid and mucoaqueous layers.METHODS:In this cross-sectional study,patients with dry eye,meibomian gland dysfunction(MGD),and non-dry eye/MGD from February 2020 to January 2021 were analyzed.Quantified TFI outputs included lipid layer thickness(LLT),mucoaqueous layer thickness(MALT),MALT rate of change(MALTR),and lipid breakup time.Two other interferometry devices,LipiView2 and DR-1α,were used for comparison.TFI outputs and other clinical parameters were analyzed using correlation coefficients.Each patient underwent one or several study visits.Baseline values of three device outputs,other clinical parameters,and their changes were examined.RESULTS:This study involved 28 patients(8 patients with dry eyes,13 with MGD,and 7 with non-dry eye/MGD).Baseline TFI,LipiView2,and DR-1αvalues were associated with various clinical parameters.The LLT values estimated using TFI had a correlation with the plugging score in the upper eyelid(r=−0.42).Several TFI values have correlated better than LipiView2 and DR-1α,particularly with questionnaire scores.MALTR by TFI revealed a correlation between standardized patient evaluation on eye dryness(SPEED)and dry eye-related quality of life score(DEQS)scores(r=0.59,0.43),respectively.CONCLUSION:TFI enabled to quantify the LLT and MALT separately over time and shows the moderate correlations between TFI measurements and clinical parameters,which yields the potential for TFI to serve as a complementary tool for assessing dry eye and MGD. 展开更多
关键词 dry eye lipid layer thickness meibomian gland dysfunction mucoaqueous layer thickness tear film imager
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Optical coherence tomography findings in beta-thalassemia major:a systematic review and Meta-analysis
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作者 Maryam Firdous Muhammad Farooq Umer Suriyakala Perumal Chandran 《International Journal of Ophthalmology(English edition)》 2025年第6期1113-1122,共10页
AIM:To describe the optical coherence tomography(OCT)findings of the retinal nerve fiber layer thickness(RNFLT)and choroidal thickness(CT)in beta-thalassemia major.METHODS:A systematic search was conducted on PubMed,C... AIM:To describe the optical coherence tomography(OCT)findings of the retinal nerve fiber layer thickness(RNFLT)and choroidal thickness(CT)in beta-thalassemia major.METHODS:A systematic search was conducted on PubMed,Cochrane,and Embase using a combination of specific key words.The records found were screened in two phases(title/abstract,and full-text screening).All the original observational cross-sectional studies conducted on beta-thalassemia major cases and controls reporting the RNFLT and CT were included.The Meta-analysis was run for comparing the OCT measurements between betathalassemia cases and controls including pooled effect size,confidence intervals(CI),quality assessment,and publication bias.The measurements included were RNFLT(average,and in various quadrants),and CT.RESULTS:A total of 10 studies were included in this Meta-analysis including a total of 684 individuals,362 cases and 322 controls.The RNFLT and CT showed a significant reduction in the values of beta-thalassemia cases as compared to controls.The heterogeneity among the included studies was found to be 92.65%for the average RNFLT and 30.13%for the CT making it obvious to use random effects model for analyzing the RNFLT values while fixed effects model for the CT.The Egger’s test showed significant publication bias among all the parameters except for nasal RNFLT(P=0.507),and CT(P=0.281).The estimated average effect size for the average RNFLT was 1.04(95%CI:0.35 to 1.72,Z=2.961,P=0.003)and for CT was 0.74(95%CI:0.51 to 0.96,Z=6.523,P<0.001).CONCLUSION:This Meta-analysis concludes that the RNFLT and CT are significantly thinner in beta-thalassemia cases in comparison to healthy individuals.Therefore,the RNFLT and CT must be evaluated in routine clinical practice in order to avoid irreversible vision loss particularly in betathalassemia individuals. 展开更多
关键词 BETA-THALASSEMIA retinal nerve fiber layer thickness choroidal thickness optical coherence tomography
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Multi-omics integration reveals Chr1 associated QTL mediating backfat thickness in pigs
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作者 Naibiao Yu Dengshuai Cui +3 位作者 Chenyu Li Siyu Yang Chuanmin Qiao Lei Xie 《Journal of Animal Science and Biotechnology》 2025年第6期2641-2657,共17页
Background Backfat thickness(BFT)is a vital economic trait in pigs,reflecting subcutaneous fat levels that affect meat quality and production efficiency.As a complex trait shaped by multiple genetic factors,BFT has be... Background Backfat thickness(BFT)is a vital economic trait in pigs,reflecting subcutaneous fat levels that affect meat quality and production efficiency.As a complex trait shaped by multiple genetic factors,BFT has been studied using genome-wide association studies(GWAS)and linkage analyses to locate fat-related quantitative trait loci(QTLs),but pinpointing causal variants and genes is hindered by linkage disequilibrium and limited regulatory data.This study aimed to dissect the QTLs affecting BFT on Sus scrofa chromosome 1(SSC1),elucidating regulatory variants,effector genes,and the cell types involved.Results Using whole-genome genotyping data from 3,578 pigs and phenotypic data for five BFT traits,we identified a 630.6 kb QTL on SSC1 significantly associated with these traits via GWAS and fine-mapping,pinpointing 34 candidate causal variants.Using deep convolutional neural networks to predict regulatory activity from sequence data integrated with detailed pig epigenetic profiles,we identified five SNPs potentially affecting enhancer activity in specific tissues.Notably,rs342950505(SSC1:161,123,588)influences weak enhancer activity across multiple tissues,including the brain.High-throughput chromosome conformation capture(Hi-C)analysis identified that rs342950505 interacts with eight genes.Chromatin state annotations confirmed enhancer activity at this QTL in the cerebellum.Leveraging these insights,single-cell ATAC-seq revealed a chromatin accessibility peak encompassing rs342950505 that regulates PMAIP1 expression in inhibitory neurons via enhancer-mediated mechanisms,with an adjacent peak modulating CCBE1 expression in neuroblasts and granule cells.Transcriptome-wide association studies(TWAS)confirmed PMAIP1's role in the hypothalamus,and Mendelian randomization(MR)validated PMAIP1 and CCBE1 as key brain expression quantitative trait locus(eQTL)effectors.We propose that the variant rs342950505,located within a regulatory peak,modulates PMAIP1 expression in inhibitory neurons,potentially influencing energy homeostasis via hypothalamic regulation.Similarly,CCBE1 may contribute to this process.Conclusions Our results,through systematic dissection of pleiotropic BFT-associated loci,provide a framework to elucidate regulatory mechanisms of complex traits,offering insights into polygenic control through lipid metabolism and neural signaling pathways. 展开更多
关键词 Backfat thickness Deep learning GWAS Multi-omics PIG
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Research Progress of Microstructure Regulation on the Electrical Properties of PZT Ferroelectric Films
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作者 Hefa Zhu Zhiguo Xing +5 位作者 Haidou Wang Longlong Zhou Wei Peng Qingbo Mi Han Dong Weiling Guo 《Chinese Journal of Mechanical Engineering》 2025年第6期470-486,共17页
Lead zirconate titanate(PbZr_(x)Ti_(1-x)O_(3),PZT)ferroelectric films possess remarkable characteristics such as high residual polarization,high dielectric constant,and high piezoelectric coefficient and have great ap... Lead zirconate titanate(PbZr_(x)Ti_(1-x)O_(3),PZT)ferroelectric films possess remarkable characteristics such as high residual polarization,high dielectric constant,and high piezoelectric coefficient and have great application prospects in modern electronics,communications,medical care,and military fields.At present,the microstructure changes of PZT ferroelectric thin films have a significant impact on their electrical properties.Therefore,this work summarizes the influences of geometric structure(thickness,porosity),composition structure(Zr/Ti ratio,doping),and grain structure(grain size,grain boundaries,orientation)on the electrical properties of PZT ferroelectric thin films.The results show that the changes in thickness and porosity have a significant impact on the electrical properties of PZT ferroelectric films.Especially,the actual application scenarios and preparation processes determine the required geometric dimensions and structures of PZT ferroelectric films.The Zr/Ti ratio and doping mainly affect the electrical properties by influencing the phase composition of PZT ferroelectric films.The changes in grain size,boundary structure,and orientation dependence mainly have a certain degree of influence on the domain response and domain switching behavior of PZT ferroelectric thin films.In conclusion,different structures have different influence effects on the dielectric,ferroelectric,and piezoelectric properties of PZT ferroelectric films.The way the tiny structure affects how PZT thin films work was shown,helping to guide the design of ferroelectric thin film devices.In order to further study and apply piezoelectric ceramic devices,it is crucial to have an in-depth understanding of the relationship between the structure and performance of piezoelectric ceramic devices. 展开更多
关键词 PZT films Thickness POROSITY DOPING Grain size Grain boundary ORIENTATION
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