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Film thickness effect on 2D lead-free hybrid double perovskite properties: Band gap, photocurrent and stability 被引量:1
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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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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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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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Enhancing Solar Photovoltaic Efficiency:A Computational Fluid Dynamics Analysis
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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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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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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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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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“Lightning survivors” in the forest
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作者 高云 《疯狂英语(新读写)》 2025年第8期52-53,78,79,共4页
Activity 1 Think about the following questions and write down your answers before reading the text.1.What are some common factors that usually cause damage to trees when they are struck by lightning?2.How might the un... Activity 1 Think about the following questions and write down your answers before reading the text.1.What are some common factors that usually cause damage to trees when they are struck by lightning?2.How might the unique characteristics of a tree contribute to its ability to survive a lightning strike? 展开更多
关键词 LIGHTNING bark thickness root system think following questions trees SURVIVAL FOREST moisture content
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ANN-based prediction model for single-hole water inflow from piedmont to inland plain areas of Hebei Province, North China Plain
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作者 Hong-wei Song Fan Xia +2 位作者 Wei-qiang Wang Ming-sen Shang Jian-ye Gui 《Journal of Groundwater Science and Engineering》 2025年第4期434-448,共15页
This study,based on Artificial Neural Network(ANN)technology,develops a quantitative prediction model for the unit water flow rate of the Quaternary strata in the Shijiazhuang-Hebei Plain area.The study area extends f... This study,based on Artificial Neural Network(ANN)technology,develops a quantitative prediction model for the unit water flow rate of the Quaternary strata in the Shijiazhuang-Hebei Plain area.The study area extends from the piedmont region of Shijiazhuang,at the eastern foothills of the Taihang Mountains,to the hinterland area of Hengshui within the plain in Hebei Province section of the North China Plain.The hydrological and exploration boreholes selected for modeling are primarily located in the south-eastern part of Shijiazhuang urban area—the southern region of Xinji County—north of Hengshui City near the Shenzhou County area.By employing the Induced Polarization method(IP)and Vertical Electrical Sounding(VES),apparent resistivity(ρS),apparent polarization rate(ηS),half-decay time(Th),and decay degree(D)were obtained as initial input parameters.These were combined with the measured water flow rates from borehole pumping tests to build the training sample set.To address the prevalent issue of high-salinity interference in the study area,multiple regression analysis revealed that when the inverted resistiv-ity(ρ)is less than 5Ω·m and the inverted polarization rate(η)is greater than 8%,the contribution of groundwater salinity to the resistivity parameter reaches 42%±6%.Based on this,a comprehensive parame-ter T"=ρ*H/ρ'was established,whereρis the aquifer resistivity,ρ'is the aquitard resistivity,and H is the aquifer thickness.The resistivity ratio effectively eliminates the coupling effect between electrical parame-ters and salinity.The input neurons of the improved model were adjusted to a four-parameter system consisting of decay time(Th),decay degree(D),deviation degree(σ),and the comprehensive parameter(T").Experiments showed that the prediction error of the model on the validation set was reduced from the original model's 5%-10%to 0.9%-5%.The introduction of the T"parameter reduced the prediction error in high salinity areas(Cl->500 mg/L)to within 7%.The study confirms that the composite parameter T"based on geophysical inversion parameters can effectively characterize the coupling features of aquifer thickness and water quality.Even with a small sample size,through algorithm optimization,data augmentation,and model structural improvements,it is entirely possible to effectively enhance prediction accuracy and gener-alization ability,providing a new parameterization method for the quantitative evaluation of Quaternary pore water in plain areas. 展开更多
关键词 Artificial Neural Network SINGLE-HOLE Aquifer Thickness RESISTIVITY Induced Polarization
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Overcoming transparency limitations in 3D-printed yttria ceramics
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作者 Sinuo Zhang Chang Woo Gal +5 位作者 Imam Akbar Sutejo Shakeel Abbas Yeong-Jin Choi Ha-Neul Kim Young-Jo Park Hui-suk Yun 《Journal of Materials Science & Technology》 2025年第22期59-71,共13页
Microstructure and surface roughness are two critical factors governing the transparency of transparent ceramics.The manufacturing mechanism of additive manufacturing(AM)layer by layer is destined that the layer thick... Microstructure and surface roughness are two critical factors governing the transparency of transparent ceramics.The manufacturing mechanism of additive manufacturing(AM)layer by layer is destined that the layer thickness has an important influence on the microstructure and surface quality of the printed workpiece.Simultaneously,the occurrence of the stair-stepping phenomenon unavoidably results in a significant surface roughness.Therefore,in this study,yttria(Y_(2)O_(3))transparent ceramics with different printing layer thicknesses were fabricated by AM to investigate the effect of layer thickness on its optical and mechanical properties.The findings indicate that an increase in the layer thickness correlates with a heightened density in the printed green bodies,subsequently leading to enhanced transmittance in the final sintered body.When the layer thickness approximates or falls below the size of large particle agglomerations found in ceramic powders,numerous pores,and voids emerge within the green bodies.Significantly,at a layer thickness of 45µm,the in-line transmittance of Y_(2)O_(3)can reach up to 97.73%of the theoretical limit.In addition,the surface roughness of the Y_(2)O_(3)ceramics decreased as the layer thickness increased.To facilitate the further transition from translucent to transparent 3D Y_(2)O_(3)structures,a vibration-assisted chemical-mechanical polishing technique was developed by replacing water with a colloidal SiO_(2) suspension.This technique resulted in a significant reduction in the surface roughness of the Y_(2)O_(3)ceramics by 95.42%and eliminated the stair-stepping phenomenon caused by AM,thus increasing 66.12%of the in-line transmittance.These enhancements expand their potential applications in laser amplification,optical communications,and other areas requiring high-transparency materials.The method developed in this study can be used for the AM-based fabrication of transparent 3D polycrystalline ceramics. 展开更多
关键词 Additive manufacturing YTTRIA Layer thickness Surface roughness Optical properties
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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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