53 results on '"Zidong Chen"'
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2. Effectiveness and Safety of Vitrectomy Combined with Cataract Surgery Concurrently Versus Vitrectomy with Subsequent Cataract Surgery for Proliferative Diabetic Retinopathy Patients with Mild-moderate Cataract: A Multicenter Randomized Controlled Study
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weibo feng, Lei Zheng, Guoming Zhang, xian wang, yingqi li, Yonghao Li, Bingqian Liu, Ling Jin, yinuo huang, Yangfan Yang, Zidong Chen, Dahui Ma, Qingshan Chen, chaojun qin, bingmin feng, zhumin yang, xing huang, chengjie yang, shenghui liu, and Mingxing Wu
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Purpose To evaluate the effectiveness and safety of pars plana vitrectomy (PPV) combined with phacoemulsification and intraocular lens implantation in proliferative diabetic retinopathy (PDR) patients over 45 years old with mild-moderate cataract, in comparison with PPV with subsequent cataract surgery. Methods This multi-center randomized controlled trial was conducted in three Chinese hospitals. From February 2021 to October 2021, 168 PDR patients were assessed for eligibility. After exclusion, a total of 129 patients were recruited and randomly assigned to PPV combined with cataract surgery concurrently (the combined group) or PPV with subsequent cataract surgery 6 months later (the subsequent group). A 12-month follow-up period was scheduled. Changes of best correct visual acuity (BCVA), rate of complications were compared between groups. Results 66 patients were assigned to the combined group and 63 to the subsequent group. The change of BCVA in the combined group with mean 36.90 (95% confidence interval, 95% CI: 30.35-43.45) letters was significantly better (adjusted difference of 16.43, 95% CI: 8.77-24.08, P<0.001) than the subsequent group with 22.40 (95% CI: 15.55-29.24) letters 6 months after the PPV, and no significant difference was found after the cataract surgery in the subsequent group. Compared with the combined group, the rates of neovascular glaucoma (17.65% vs. 3.77%, P=0.005) were significantly higher in the subsequent group. Conclusion Compared with PPV with subsequent cataract surgery, PPV combined with cataract surgery concurrently was relatively effective, convenient and safe, being a promising and reliable surgical option for PDR patients over 45 years old with mild-moderate cataract. Trial registration number NCT04729023.
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- 2023
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3. Intraocular pressure and diurnal fluctuation of open-angle glaucoma and ocular hypertension: a baseline report from the LiGHT China trial cohort
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Yangfan, Yang, Xinyi, Zhang, Zidong, Chen, Yifan, Wei, Qiaona, Ye, Yanmei, Fan, Neil, Nathwani, Gus, Gazzard, Minbin, Yu, and Yunzhi, Xu
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Cellular and Molecular Neuroscience ,Ophthalmology ,genetic structures ,sense organs ,eye diseases ,Sensory Systems - Abstract
AimsTo report the baseline intraocular pressure (IOP) characteristics and its diurnal fluctuation in the Laser in Glaucoma and Ocular Hypertension China cohort.Methods622 primary open-angle glaucoma (POAG) patients and 149 ocular hypertension (OHT) patients were recruited at Zhongshan Ophthalmic Center from 2015 to 2019. Standardised ocular examinations were performed including IOP measurement using the Goldmann applanation tonometer. Daytime phasing IOP was recorded at 8:00, 10:00, 11:30, 14:30, 17:00 hour.ResultsThe mean baseline IOP was 20.2 mm Hg for POAG patients and 24.4 mm Hg for OHT. Multiple regression analysis revealed that thicker central corneal thickness (CCT) was correlated with higher IOP in both POAG and OHT. Male gender and younger age were correlated with higher IOP only for POAG. As for diurnal IOP fluctuation, mean IOP fluctuation was 3.4 mm Hg in POAG eyes and 4.4 mm Hg in OHT. The peak and trough IOP occurred at 8:00 and 14:30 hour in both POAG and OHT eyes.ConclusionsYounger age, male gender and thicker CCT are correlated to higher IOP in POAG patients while only thicker CCT is related to higher IOP in OHT patients. Peak IOP appears mostly at early morning or late afternoon and trough value occurs mostly at early afternoon.
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- 2022
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4. Li-Alloy Texture Creates In-Built Li(110) Epitaxy in Thin Li-Metal Anode Allowing High Depth-of-Discharge Cycling in Carbonate Electrolyte
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Yuhang Hu, Hao Li, Zidong Chen, Wanglai Cen, Qiang Wang, Yungui Chen, Ali Davoodi, and Wei Liu
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- 2023
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5. Perceptual Quality Assessment of TTS-Synthesized Speech
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Zidong Chen and Xiongkuo Min
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- 2023
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6. The risk of glaucoma associated with phacomatosis cesioflammea and phacomatosis cesioflammeo-marmorata
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Shitong, Huang, Yangfan, Yang, Zhikun, Ouyang, Xiujuan, Guo, Zongyi, Zhan, Xing, Liu, Zidong, Chen, Jiangang, Xu, and Minbin, Yu
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Tuberous Sclerosis ,Hyperpigmentation ,Neurocutaneous Syndromes ,Humans ,Glaucoma ,Prospective Studies - Abstract
The ocular features of phacomatosis pigmentovascularis (PPV) have rarely been reported, and glaucoma is the leading cause of blindness in patients with this condition. To protect vision in these patients, it is important to identify glaucoma as early as possible.To systematically report the systemic and ocular manifestations of phacomatosis cesioflammea and phacomatosis cesioflammeo-marmorata, and to investigate a glaucoma risk scoring system.In this prospective study, patients with PPV from 2014 to 2021 were included. Clinical information was collected, and associations with glaucoma were evaluated. The suitability of the scoring system was assessed. A systematic literature review and analysis of reported cases of PPV was performed.A total of 28 participants with PPV were included. Their ocular findings were similar, ranging from episcleral hyperpigmentation (78.5%), glaucoma (75%), choroid haemangioma (38%), and retinal vascular abnormalities (48%), to hyperpigmentation of the cornea, iris, lens and fundus. Glaucoma was associated with multiple factors, especially a thick choroid (odds ratio: 2.61; p = 0.008) and a diffuse mass-type of episcleral hyperpigmentation (odds ratio: 41.3; p = 0.027). The risk scoring system was characterized by high sensitivity (84%) and specificity (80%; AUC = 0.91) in predicting glaucoma.In addition to involving the systemic system, phacomatosis cesioflammea and phacomatosis cesioflammeo-marmorata also represent a specific spectrum of ophthalmic vascular malformations and hyperpigmentation. Early and periodic detailed ocular examination are recommended. The novel scoring system will help to tailor follow-up for visual protection.
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- 2022
7. 'Sticky' carbon coating enables high-area-capacity lithium storage of silicon-graphitic carbon hybrid
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Zheng Zhang, Bo Xie, Ali Davoodi, Yungui Chen, Hao Li, Zidong Chen, Lun Li, Saman Hosseinpour, and Wei Liu
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Materials science ,Silicon ,chemistry.chemical_element ,Nanoparticle ,General Chemistry ,engineering.material ,Anode ,Coating ,Chemical engineering ,chemistry ,engineering ,General Materials Science ,Lithium ,Graphite ,Layer (electronics) ,Carbon - Abstract
Pulverization and surface instability have been identified as the main impediments to the application of Si anodes in high-energy lithium-ion batteries (LIBs). In this study, a Si-graphitic carbon hybrid (SiG) is created via embedding Si nanoparticles in between expanding graphite interlayers, thus to be adopted as a model system to unravel structure-properties relations for LIBs applications. We explore the impact of artificial surface coating layers on the lithium cycling performance of SiG particles. In comparison with native SiG and carbon-coated SiG (CC-SiG), we find that the “sticky-carbon” coating, i.e., an epoxy-rich layer on top of the carbon coating, gave rise to superior cycle performance. In the “sticky carbon” coated SiG (SCC-SiG), the surface chemistry appears to have a pivotal role in both alleviating electrode disintegration and forming a favorable SEI rich in fluorine-polymers. These positive findings are examined in electrodes with mass loading ranging from 1.0 to 5.0 mg/cm2, achieving area capacities up to ∼5.0 mAh/cm2. A full cell adopting >6 mg/cm2 LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode and SCC-SiG delivers stable cycling performances. It is hence unraveled that the carbon coating layer with reactive surface groups on the top is an unrecognized key for wide range of Si-based anodes.
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- 2021
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8. A Time-to-Digital Converter Based on Looping and Averaging Logic for Accuracy Improvement
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Zhiwei Huang, Zidong Chen, Chongzhuo Zhao, Chuanxin Teng, and Shijie Deng
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- 2022
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9. An Element Sharing Based Dynamic Range Adjustable Time-to-Digital Converter
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Chongzhuo Zhao, Zidong Chen, Zhiwei Huang, Chuanxin Teng, and Shijie Deng
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- 2022
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10. Li-Alloy texture creates in-built Li(110) epitaxy in a thin Li-metal anode allowing high depth-of-discharge cycling in carbonate electrolyte
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Yuhang Hu, Hao Li, Zidong Chen, Wanglai Cen, Qiang Wang, Yungui Chen, Ali Davoodi, and Wei Liu
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General Chemical Engineering ,Environmental Chemistry ,General Chemistry ,Industrial and Manufacturing Engineering - Published
- 2023
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11. Higher contrast thresholds for vanishing optotype recognition in macular visual fields among glaucoma patients: a structure–function analysis
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Kaixin Tan, Hui Cheng, Zidong Chen, Yun Wen, Shuo Chen, Minbin Yu, and Yang Kong
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Adult ,medicine.medical_specialty ,genetic structures ,media_common.quotation_subject ,Visual Acuity ,Glaucoma ,Spectral domain ,Young Adult ,Cellular and Molecular Neuroscience ,Nerve Fibers ,Optical coherence tomography ,Ophthalmology ,medicine ,Humans ,Contrast (vision) ,Intraocular Pressure ,media_common ,medicine.diagnostic_test ,business.industry ,Structure function ,medicine.disease ,Inner plexiform layer ,eye diseases ,Sensory Systems ,Pattern vision ,Visual field ,medicine.anatomical_structure ,Visual Field Tests ,sense organs ,Visual Fields ,business ,Glaucoma, Open-Angle ,Tomography, Optical Coherence - Abstract
Background/aimsWe aimed to explore the impact of glaucomatous macular damage, specifically retinal ganglion cell (RGC) loss, on macular pattern vision measured by the vanishing optotype (VO) recognition contrast threshold.MethodsSeventy-two patients (mean age, 33.51±7.05 years) with primary open-angle glaucoma and 36 healthy controls (mean age, 30.25±6.70 years) were enrolled. VO recognition contrast thresholds of each participant were measured at the 16 preset test locations covering the central 5° visual field (VF). Macular sensitivity (MS) was tested by macular threshold test of Humphrey Field Analyzer. Macular RGC plus inner plexiform layer (GCIPL) thickness was also measured by spectral domain optical coherence tomography.ResultsThe VO contrast threshold demonstrated weak-to-moderate correlations (rho=−0.275 to −0.653) with MS (pConclusionsGlaucomatous eyes have higher contrast thresholds for VO recognition in fovea-around VF. Stronger structure–function relationships indicate that VO contrast threshold is more vulnerable to RGC damage.
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- 2021
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12. A New Contact Lens Sensor System for Continuous Intraocular Pressure Monitoring: Evaluation of Safety and Tolerability
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Yuning Zhang, Yifan Wei, I. K. Karunaratne, Ching Hymn Christopher Lee, Mingjie Deng, Zidong Chen, Yangfan Yang, Iok Tong Chong, David C. C. Lam, and Minbin Yu
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Ophthalmology ,Tonometry, Ocular ,Fatigue Syndrome, Chronic ,Contact Lenses ,Humans ,Glaucoma ,Prospective Studies ,Fluoresceins ,Intraocular Pressure ,Circadian Rhythm - Abstract
To assess the safety and tolerability of a new contact lens sensor (CLS) system for continuous 3- and 24-hr intraocular pressure (IOP) monitoring in human eyes.Twenty-five subjects were recruited for 3-hr IOP measurement by CLS. Corneal fluorescein staining (CFS) scores were evaluated before and after measurement. Then, 30 participants (10 normal subjects and 20 glaucoma patients) were recruited for 24-hr IOP monitoring. Ocular surface disease index (OSDI) was assessed before and one day after measurement. Contact lens dry eye questionnaire-8 was assessed immediately after measurement. Visual analog scale of discomfort was measured before, immediately after, and one day after measurement. Best-corrected visual acuity (BCVA), tear break-up time (TBUT), and CFS were assessed before, immediately after, and 1 day after measurement.All participants completed 3- or 24-hr IOP measurement by CLS. Corneal fluorescein staining increased from 0.6±0.7 to 2.4±1.5 after 3-hr IOP measurement ( P0.001). For participants undergoing 24-hr IOP monitoring, OSDI increased from 9.1±9.7 to 18.0±12.4 ( P =0.001). CLDEQ-8 score was 11.6±5.8. Visual analog scale increased from 11.1±14.2 to 35.2±21.8 after measurement ( P0.001) and decreased to 26.7±18.4 one day later ( P0.001 compared with baseline). BCVA decreased from 1.0±0.01 to 0.8±0.1 ( P0.001) and returned to 0.9±0.1 after one day ( P0.001 compared with baseline). TBUT decreased from 5.1±3.9 to 2.6±1.5 s ( P =0.001) and returned to 4.8±2.5 s ( P =0.465 compared with baseline). Corneal fluorescein staining increased from 0.7±0.9 to 4.3±0.8 ( P0.001) and dropped to 0.8±0.7 ( P =0.599 compared with baseline). No significant difference was found for all variations of indicators between normal subjects and glaucoma patients ( P0.1 for all comparisons).The CLS shows a great potential for a safe and tolerable 24-hr IOP monitoring in normal subjects and glaucoma patients. Clinical attention to the worsening signs and symptoms after measurement is required.
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- 2022
13. Lithium-activated SnS–graphene alternating nanolayers enable dendrite-free cycling of thin sodium metal anodes in carbonate electrolyte
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Zheng Zhang, Wei Liu, Yixian Wang, David Mitlin, Zidong Chen, Eunsu Paek, Pingxian Jiang, and Yungui Chen
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Materials science ,Nanocomposite ,Renewable Energy, Sustainability and the Environment ,Graphene ,Sodium ,chemistry.chemical_element ,Electrolyte ,Pollution ,Cathode ,law.invention ,Anode ,Metal ,Nuclear Energy and Engineering ,Chemical engineering ,chemistry ,law ,visual_art ,visual_art.visual_art_medium ,Environmental Chemistry ,Separator (electricity) - Abstract
Sodium metal battery (SMB, NMB) anodes can become dendritic due to an electrochemically unstable native Na-based solid electrolyte interphase (SEI). Herein Li-ion activated tin sulfide graphene nanocomposite membrane (A-SnS–G) is employed as an artificial SEI layer, allowing cyclability of record-thin 100 μm Na metal foils. The thin Na metal is prepared by a self-designed metallurgical rolling protocol. A-SnS–G is initially placed onto the polypropylene (PP) separator but becomes in situ transferred onto the Na metal surface. Symmetric metal cells protected by A-SnS–G achieve low-overpotential extended high-rate cycling in a standard carbonate electrolyte (EC : DEC = 1 : 1, 5% FEC). Accumulated capacity of 1000 mA h cm−2 is obtained after 500 cycles at 4 mA cm−2, with accumulated capacity-to-foil capacity (A/F) ratio of 90.9. This is among the most favorable cycle life, accumulated capacity, and anode utilization combinations reported. Protection by non-activated SnS–G membrane yields significantly worse cycling, albeit still superior to the baseline unprotected sodium. Post-mortem and dedicated light optical analysis indicate that metal swelling, dendrite growth and dead metal formation is extensive for the unprotected sample, but is suppressed with A-SnS–G. Per XPS, post-100 cycles near-surface structure of A-SnS–G is rich in metallic Sn alloys and inorganic carbonate salts. Even after 300 cycles, Li-based SEI components ROCO2-Li, Li2CO3 and LiF are detected with A-SnS–G. As a proof of principle, an SMB with a high mass loading (6 mg cm−2) NVP cathode and a A-SnS–G protected anode delivered extended cyclability, achieving 74 mA h g−1 after 400 cycles at 0.4C.
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- 2021
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14. Corneal Stiffness and Modulus of Normal-Tension Glaucoma in Chinese
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YUNZHI XU, YIMING YE, ZIDONG CHEN, JIANGANG XU, YANGFAN YANG, YANMEI FAN, PINGPING LIU, IOK TONG CHONG, KEMING YU, DAVID C. C. LAM, and MINBIN YU
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Cornea ,Ophthalmology ,China ,Cross-Sectional Studies ,Nerve Fibers ,Optic Disk ,Humans ,Glaucoma ,Low Tension Glaucoma ,Prospective Studies ,Glaucoma, Open-Angle ,Intraocular Pressure ,Tomography, Optical Coherence - Abstract
To assess and compare the corneal biomechanics of normal-tension glaucoma (NTG), high-tension glaucoma (HTG), and normal controls based on stiffness and modulus. The correlations among central corneal thickness (CCT), visual field, retinal nerve fiber layer (RNFL) thickness, and corneal biomechanics in glaucoma eyes were also evaluated.A prospective, cross-sectional, comparative study.This study included 334 eyes of 108 NTG patients, 113 HTG patients, and 113 control subjects at Zhongshan Ophthalmic Center, Sun Yat-Sen University. Corneal biomechanics were evaluated using a corneal indentation device (CID) and corneal visualization Scheimpflug technology (Corvis ST). Visual field and RNFL thickness were obtained using standard automated perimetry and spectral-domain optical coherence tomography. One-way analyses of variance with Bonferroni post hoc tests and a multivariable linear regression analysis with adjustment were conducted. Correlations among corneal biomechanical parameters, CCT, visual field, and RNFL thickness were analyzed.The corneal stiffness of the NTG patients (71.0 ± 10.9 N/m) was significantly lower than that of the HTG patients (77.3 ± 15.6 N/m; P = .001) and the CCT- and IOP-matched normal controls (75.6 ± 11.0 N/m; P = .023). The patients in the NTG group had lower corneal stiffness than those in the control group (β = -4.88, 95% CI -9.002, -0.758; P = .020) after adjusting for confounders. Stiffness was positively correlated with CCT in the NTG group (P = .028) but not in the HTG group (P = .509). There was no significant correlation (P.05) between corneal biomechanics, visual field, or RNFL thickness.The corneas of NTG patients were softer than those of HTG patients and controls, as assessed by CID, which were associated with thinner CCT. These might suggest different ocular biomechanical properties in NTG and HTG.
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- 2022
15. Visual Crowding Reveals Field- and Axis-Specific Cortical Miswiring After Long-Term Axial Misalignment in Strabismic Patients Without Amblyopia
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Yiru Huang, Zitian Liu, Zidong Chen, Zongyi Zhan, Le Gao, Jingyi Hu, Yanyan Wu, Fang-Fang Yan, Daming Deng, Chang-Bing Huang, and Minbin Yu
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General Medicine - Published
- 2023
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16. Campus Sentiment Analysis with GAN-based Data Augmentation
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Yu Shang, Xiaohui Su, Zhifeng Xiao, and Zidong Chen
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- 2021
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17. Synergy of Epoxy Chemical Tethers and Defect‐Free Graphene in Enabling Stable Lithium Cycling of Silicon Nanoparticles
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Eunsu Paek, Jialun Jin, Qin Wang, Hongju Li, Wei Liu, Zidong Chen, Yizhe Wang, David Mitlin, Zheng Zhang, and Yungui Chen
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Materials science ,Silicon ,010405 organic chemistry ,Graphene ,chemistry.chemical_element ,General Medicine ,General Chemistry ,Electrolyte ,Epoxy ,010402 general chemistry ,01 natural sciences ,Silane ,Catalysis ,0104 chemical sciences ,law.invention ,Anode ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,visual_art ,visual_art.visual_art_medium ,Graphite ,Faraday efficiency - Abstract
We report a new approach for nanosilicon-graphene hybrids with uniquely stable solid electrolyte interphase. Expanded graphite is gently exfoliated creating "defect-free" graphene that is non-catalytic towards electrolyte decomposition, simultaneously introducing high mass loading (48 wt. %) Si nanoparticles. Silane surface treatment creates epoxy chemical tethers, mechanically binding nano-Si to CMC binder through epoxy ring-opening reaction while stabilizing the Si surface chemistry. Epoxy-tethered silicon pristine-graphene hybrid "E-Si-pG" exhibits state-of-the-art performance in full battery opposing commercial mass loading (12 mg cm-2 ) LiCoO2 (LCO) cathode. At 0.4 C, with areal capacity of 1.62 mAh cm-2 and energy of 437 Wh kg-1 , achieving 1.32 mAh cm-2 , 340.4 Wh kg-1 at 1 C. After 150 cycles, it retains 1.25 mAh cm-2 , 306.5 Wh kg-1 . Sputter-down XPS demonstrates survival of surface C-Si-O-Si groups in E-Si-pG after repeated cycling. The discovered synergy between support defects, chemical-mechanical stabilization of Si surfaces, and SEI-related failure may become key LIB anode design rule.
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- 2019
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18. Ocular Motor Behavior Monitor in Intermittent Exotropia by Eye Tracker
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Xiaoxiao Cai, Yanping Liu, Zidong Chen, Zitian Liu, Minbin Yu, and Daming Deng
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genetic structures ,business.industry ,Ocular motor ,education ,Medicine ,Optometry ,Eye tracking ,sense organs ,business ,Intermittent exotropia ,eye diseases - Abstract
Purpose: Eye movement in intermittent exotropia (IXT) patients is characterized by viability and uncertainty, however, conventional strabismus inspection methods cannot reflect these important qualities. Here, we sought to study the ocular motor behavior of IXT under different viewing conditions by eye tracker.Methods: Sixty-one IXT patients (33 males and 28 females) and 15 age-matched control participants were recruited for this study. An eye tracker equipped with a high-speed camera and MATLAB software was employed to monitor and record eye movement as well as eye position in included subjects with 3D shutter glasses at a normal reading distance (57 cm).Results: By using an eye tracker, our data showed that 90% of the included IXT patients lost their control and showed exotropia in 1.5±2.1s. The average deviation degree measured by the eye tracker was 32.9±11.5△, ranging from 6 to 50△, and reached its maximum deviation degree at 36.9±12.4△, with a mean time of 2±1.5s. Although a significant difference exists in the strabismus quantification between the prism test and the eye tracker, the test results obtained from these two methods were positively correlated. Moreover, by using the eye tracker, the fixation instability of IXT patients could be easily recorded and analyzed. In addition, the included IXT patients were divided into three types according to their ocular motor behavior as monitored by an eye tracker.Conclusion: Eye trackers could not only provide continuous, precise and effective strabismus assessments but also analyze ocular motor behavior over a period of time in IXT patients.
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- 2021
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19. The Impact of Cataract Surgery on Vision-Related Quality of Life and Psychological Distress in Monocular Patients
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Xuepei Li, Jianqiang Lin, Zidong Chen, Guangming Jin, and Danying Zheng
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Ophthalmology ,Article Subject ,genetic structures ,sense organs ,RE1-994 ,behavioral disciplines and activities ,eye diseases ,Research Article - Abstract
Purpose. To determine the changes in vision-related quality of life and psychological distress after cataract surgery in monocular patients and to compared these with a control group of age- and gender-matched binocular patients. Methods. We enrolled 40 monocular patients and 40 binocular patients who underwent cataract surgery from August 2017 to December 2018. All participants undertook eye examinations and answered questionnaires (the National Eye Institute Visual Function Questionnaire, Self-rating Anxiety Scale, and Self-rating Depression Scale) before and after cataract surgery. Result. The monocular patients had significantly worse mean CDVA than the binocular patients before and after surgery. However, there was no significant difference between the increases gained by the two groups. Mean composite VFQ-25 scores of the monocular group were significantly lower than those of the binocular group before and after surgery, but the improvement experienced by the monocular group was statistically larger than the binocular group (37.20 ± 12.84 vs. 19.11 ± 5.13, P < 0.001 ). Mean standard SAS scores of monocular patients were significantly higher than those of binocular controls before and after surgery, while monocular patients experienced a significant greater decline of SAS scores (−9.41 ± 5.39 VS −3.84 ± 1.61, P < 0.001 ). Mean standard SDS scores of the monocular group were significantly higher than those of the control group before and after surgery, but the monocular group experienced a significantly greater decline of SDS scores following cataract surgery (−11.91 ± 6.38 VS −4.78 ± 1.79, P < 0.001 ). There was a significant correlation between the preoperative logMAR CDVA and both the postoperative logMAR CDVA (r = 0.63, P < 0.001 ) and the changes in the logMAR CDVA (r = −0.881, P < 0.001 ) for monocular patients. Linear regression analyses suggested that higher postoperative VFQ-25 scores had significant associations with better preoperative CDVA and the absence of systemic comorbidity (both P < 0.05 ). Age and ocular comorbidity were significantly associated with postoperative SAS scores (both P < 0.05 ). Age and systemic comorbidity remained significant impact factors for SDS scores (both P < 0.05 ). Conclusion. Monocular patients reported greater improvement in vision-related quality of life and greater decline in the level of anxiety and depression than binocular control subjects, despite having similar CDVA gains after cataract surgery. We argue that it is not a better choice for monocular patients to delay cataract surgery until the cataract is very advanced. A clear understanding of the impact of cataract surgery on vision-related quality of life and psychological distress in monocular patients is needed by ophthalmologists when making surgery decision.
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- 2021
20. Low-Contrast High-Pass Visual Acuity Might Help to Detect Glaucoma Damage: A Structure-Function Analysis
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Zidong Chen, Jiangang Xu, Yangfan Yang, Minbin Yu, Hui Cheng, Chengguo Zuo, Yun Wen, and Yang Kong
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Medicine (General) ,medicine.medical_specialty ,Visual acuity ,genetic structures ,media_common.quotation_subject ,Nerve fiber layer ,Glaucoma ,low-contrast visual acuity ,03 medical and health sciences ,chemistry.chemical_compound ,R5-920 ,0302 clinical medicine ,Chart ,Optical coherence tomography ,Ophthalmology ,medicine ,Contrast (vision) ,Original Research ,media_common ,optical coherence tomography ,medicine.diagnostic_test ,business.industry ,macular damage ,Structure function ,Retinal ,General Medicine ,medicine.disease ,eye diseases ,glaucoma ,medicine.anatomical_structure ,chemistry ,high-pass optotypes ,030221 ophthalmology & optometry ,Medicine ,sense organs ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
Purpose: The conventional visual acuity (VA) test is not sensitive enough to detect glaucoma macular damage. We aimed to investigate whether VA measurements using low-contrast high-pass optotypes are more sensitive to macular dysfunction in glaucoma and to find the potential structural basis of this difference.Methods: A total of 147 subjects were recruited, including 118 patients with glaucoma (mean age: 46.08 ± 14.64 years) and 29 healthy controls (mean age: 39.83 ± 9.81 years). For each participant, monocular best-corrected VA was measured using a conventional chart and six high-pass charts at 100, 50, 10, 5, 2.5, and 1.25% contrast levels, respectively. The macular retinal thickness and circumpapillary retinal nerve fiber layer (cpRNFL) thickness of all the glaucoma patients were obtained by spectral-domain optical coherence tomography (SD-OCT).Results: Compared with healthy subjects, glaucoma patients with normal vision demonstrated worse VAs in high-pass acuity measurements (0.22–0.93 vs. 0.28–1.08, p < 0.05). Receiver operating characteristic curve (ROC) showed that 1.25% low-contrast high-pass VA was optimal for discriminating between the controls and glaucoma patients (AUC: 0.918, p < 0.001; sensitivity: 77.33%; specificity: 96.55%). Compared with conventional VA, 1.25% high-pass VA correlated better with nasal-side macular retinal ganglion cell (RGC)-related parameters (r = −0.419 to −0.446 vs. r = −0.538 to −0.582; Fisher's Z transformation, pz < 0.05). There was no difference in the strength of correlations between the VAs measured using different charts and cpRNFL thickness (Fisher's Z transformation; pz > 0.05).Conclusions: VA measurement taken with low-contrast (1.25%) high-pass acuity chart is more sensitive in detecting central visual loss in glaucoma than that taken with the conventional chart. Macular RGC damage appears to be associated with low-contrast (1.25%) high-pass visual loss in glaucomatous eyes.
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- 2021
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21. Corneal Biometric Parameters and Refractive Properties in Microcornea With Normal Axial Length
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Fangyu Wang, Jiangang Xu, Minbin Yu, Zidong Chen, Zhaoxin Jiang, and Yanmei Fan
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Adult ,medicine.medical_specialty ,Biometry ,genetic structures ,Refraction, Ocular ,Cataract ,law.invention ,Corneal Diseases ,Cornea ,law ,Ophthalmology ,Medicine ,Normal axial length ,Humans ,Eye Abnormalities ,Keratometer ,business.industry ,medicine.disease ,eye diseases ,Horizontal corneal diameter ,Microcornea ,Corneal diameter ,Endothelial cell density ,Axial Length, Eye ,Congenital cataracts ,Corneal endothelial cell ,sense organs ,business - Abstract
Purpose The purpose of this study was to evaluate the features of and relationships among corneal diameter, central corneal thickness (CCT), endothelial cell density (ECD), and corneal refractive properties in cases of microcornea (MC) with normal axial length. Methods We included 22 patients (35 eyes) with MC and cataracts and 41 patients (48 eyes) with isolated cataracts as age-matched controls. They were divided into patients with MC younger than 18 years (MC-child), patients with MC 18 years or older (MC-adult), children with congenital cataracts (CCs), and adults with senile cataracts (SCs). Corneal diameter, axial and anterior chamber length, and keratometry were measured; central corneal endothelial cell imaging was performed. Results The mean horizontal corneal diameter was 7.71 ± 1.51 and 8.78 ± 0.52 mm in MC-child and MC-adult groups, respectively, and 11.89 ± 0.59 and 11.52 ± 2.42 mm in child and adult controls, respectively. The mean CCT was 641.26 ± 63.37 (MC-child) and 617.38 ± 45.40 mm (MC-adult), and 554.92 ± 34.64 (CC) and 551.58 ± 28.47 mm (SC). The mean ECD was 2898.47 ± 443.90 (MC-child) and 2825.81 ± 484.65 cells/mm2 (MC-adult), and 3155.13 ± 372.67 (CC) and 2749.33 ± 399.63 cells/mm2 (SC). The average keratometry was 44.22 ± 3.14 D (MC-child) and 43.86 ± 2.59 D (MC-adult), and 44.19 ± 1.44 D (CC) and 43.94 ± 1.34 D (SC). Conclusions Patients with MC and normal axial length possess specific parameters, including significantly smaller corneal diameter and thicker CCT than the patients in the control groups. There were no significant differences in ECD and average keratometry. These parameters should be taken into account in the follow-up and treatment.
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- 2021
22. Emerging Organic Surface Chemistry for Si Anodes in Lithium‐Ion Batteries: Advances, Prospects, and Beyond (Adv. Energy Mater. 32/2022)
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Zidong Chen, Askar Soltani, Yungui Chen, Qiaobao Zhang, Ali Davoodi, Saman Hosseinpour, Wolfgang Peukert, and Wei Liu
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Renewable Energy, Sustainability and the Environment ,General Materials Science - Published
- 2022
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23. Emerging Organic Surface Chemistry for Si Anodes in Lithium‐Ion Batteries: Advances, Prospects, and Beyond
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Zidong Chen, Askar Soltani, Yungui Chen, Qiaobao Zhang, Ali Davoodi, Saman Hosseinpour, Wolfgang Peukert, and Wei Liu
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Renewable Energy, Sustainability and the Environment ,General Materials Science - Published
- 2022
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24. Binocular Human Body Attitude Distance Localization Recognition Algorithm Based on Dual Convolution
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Wenbo Wang, Jianming Sun, and Zidong Chen
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Structure (mathematical logic) ,business.industry ,Computer science ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Human body ,Convolution ,Dual (category theory) ,Image (mathematics) ,Position (vector) ,Computer vision ,Artificial intelligence ,business ,Recognition algorithm - Abstract
Objective: An algorithm based on real-time accurate target recognition and distance location for VAVs, the existing target location and discrimination methods often fail to meet practical requirements. Method: The image information collected under the common single camera can only obtain two-dimensional information, and the relative distance of the camera based on the target cannot be obtained. However, the commonly used dual camera-based distance acquisition algorithm is too complicated, not stable enough, and requires developers to have higher the level of knowledge, the high threshold for development, and the difficulty of application. Therefore, this paper proposes to train the feature extraction network based on the two-channel Darknet-53 basic structure through the dual camera under the human body posture recognition image dataset, and initialize the YOLOv2 network with its parameters, and to train the human body position in the human body posture image, relative distance, and category. Result: Experimental results verify that the human body position and category recognition of human posture using this method improves the recognition accuracy by 3.83% and 4.81% compared with the single-convolution chain, and the accuracy of the target-based relative distance is achieved 65.21%. Conclusion: The algorithm can be effectively applied to the UAV to quickly recognize the human body posture and obtain a better recognition effect to meet the real-time demand.
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- 2020
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25. Quantifying Nasotemporal Asymmetry of Interocular Suppression in Alternating Strabismus After Correction
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Junpeng Yuan, Minbin Yu, Zidong Chen, Zitian Liu, Yun Wen, Jinrong Li, Qingshu Ge, Jing Samantha Pan, Daming Deng, and Lei Feng
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Male ,medicine.medical_specialty ,hemifield ,genetic structures ,Adolescent ,Eye Movements ,media_common.quotation_subject ,Motion Perception ,interocular suppression ,Ophthalmologic Surgical Procedures ,Asymmetry ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,Visual Psychophysics and Physiological Optics ,medicine ,Prism diopters ,Humans ,0501 psychology and cognitive sciences ,Postoperative Period ,Strabismus ,media_common ,Depth Perception ,business.industry ,05 social sciences ,medicine.disease ,eye diseases ,strabismus ,Stereopsis ,Oculomotor Muscles ,Sensory Thresholds ,030221 ophthalmology & optometry ,Female ,sense organs ,business ,Binocular vision ,Exotropia ,Esotropia ,psychological phenomena and processes ,Photic Stimulation ,Strabismus surgery - Abstract
Purpose This study identifies and characterizes the nasotemporal hemifield difference of interocular suppression in subjects who have been successfully treated for strabismus. Methods Interocular suppression in the nasal and temporal hemifields were measured using two methods, namely, binocular phase combination and dichoptic motion coherence, both entailed suprathreshold stimuli. We tested 29 clinical subjects, who had strabismus (19 with exotropia and 10 with esotropia) but regained good ocular alignment (within 10 prism diopters) after surgical or refractive correction, and 10 control subjects. Results Both the hemifield binocular phase combination and the hemifield dichoptic motion coherence tests revealed similar nasotemporal asymmetry of interocular suppression. Subjects with previous exotropia showed deeper suppression in the nasal hemifield, and those with previous esotropia showed deeper suppression in the temporal hemifield. This finding was consistent with the hemifield suppression theory. Furthermore, there was deeper suppression but less imbalance of nasotemporal asymmetry in the hemifield dichoptic motion coherence test. Finally, clinical stereopsis and the nasotemporal asymmetry of suppression (P < 0.05 in both tests) were negatively correlated in subjects with previous exotropia and measurable stereopsis. Conclusions Hemifield asymmetry of interocular suppression in corrected strabismus can be measured by using static and dynamic suprathreshold stimuli. Thus, the evaluation of binocular vision in strabismus should focus on both the magnitude and the pattern of interocular suppression.
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- 2020
26. Low-noise compliance-design for intraocular pressure contact lens sensor
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Iok Tong Chong, Ching Hymn Christopher Lee, David Chuen Chun Lam, I.K. Karunaratne, Yifan Wei, Zidong Chen, Minbin Yu, and Yangfan Yang
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Intraocular pressure ,business.industry ,Metals and Alloys ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Low noise ,Compliance (physiology) ,Contact lens ,Medicine ,Electrical and Electronic Engineering ,business ,Instrumentation ,Biomedical engineering - Published
- 2021
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27. Effects of floating gate structures on the two-dimensional electron gas density and electron mobility in AlGaN/AlN/GaN heterostructure field-effect transistors
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Fukai Xu, Zidong Chen, Zhaojun Lin, Jingtao Zhao, and Zhenguo Zhao
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010302 applied physics ,Electron mobility ,Materials science ,Field (physics) ,business.industry ,Transistor ,General Physics and Astronomy ,Heterojunction ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,law.invention ,Barrier layer ,Computer Science::Hardware Architecture ,Computer Science::Emerging Technologies ,law ,0103 physical sciences ,Coulomb ,Optoelectronics ,0210 nano-technology ,business ,Fermi gas ,Polarization (electrochemistry) - Abstract
In this study, we have investigated the electrical properties of the AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with floating gate structures using the measured capacitancevoltage (C-V) and current-voltage (I-V) characteristics. It is found that the two-dimensional electron gas (2DEG) density under the central gate cannot be changed by the floating gate structures. However, the floating gate structures can cause the strain variation in the barrier layer, which lead to the non-uniform distribution of the polarization charges, then induce a polarization Coulomb field and scatter the 2DEG. More floating gate structures and closer distance between the floating gates and the central gate will result in stronger scattering effect of the 2DEG.
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- 2017
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28. Interocular suppression in children with deprivation amblyopia
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Joanna Black, Jinrong Li, Benjamin Thompson, Junpeng Yuan, Minbin Yu, Shuan Dai, Zidong Chen, and Lisa M Hamm
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Male ,medicine.medical_specialty ,Adolescent ,genetic structures ,Visual Acuity ,Stimulus (physiology) ,Amblyopia ,Contrast Sensitivity ,Deprivation amblyopia ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Cataracts ,Ophthalmology ,Humans ,Medicine ,In patient ,Child ,Dichoptic presentation ,Vision, Binocular ,High contrast ,Adaptation, Ocular ,business.industry ,Treatment options ,medicine.disease ,eye diseases ,Sensory Systems ,Bilateral Cataracts ,Child, Preschool ,Sensory Thresholds ,030221 ophthalmology & optometry ,Female ,business ,Photic Stimulation ,030217 neurology & neurosurgery - Abstract
In patients with anisometropic or strabismic amblyopia, interocular suppression can be minimized by presenting high contrast stimulus elements to the amblyopic eye and lower contrast elements to the fellow eye. This suggests a structurally intact binocular visual system that is functionally suppressed. We investigated whether suppression can also be overcome by contrast balancing in children with deprivation amblyopia due to childhood cataracts. To quantify interocular contrast balance, contrast interference thresholds were measured using an established dichoptic global motion technique for 21 children with deprivation amblyopia, 14 with anisometropic or mixed strabismic/anisometropic amblyopia and 10 visually normal children (mean age mean=9.9years, range 5-16years). We found that interocular suppression could be overcome by contrast balancing in most children with deprivation amblyopia, at least intermittently, and all children with anisometropic or mixed anisometropic/strabismic amblyopia. However, children with deprivation amblyopia due to early unilateral or bilateral cataracts could tolerate only very low contrast levels to the stronger eye indicating strong suppression. Our results suggest that treatment options reliant on contrast balanced dichoptic presentation could be attempted in a subset of children with deprivation amblyopia.
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- 2017
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29. A Novel Indentation Assessment to Measure Corneal Biomechanical Properties in Glaucoma and Ocular Hypertension
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David Chuen Chun Lam, Minbin Yu, Yunzhi Xu, Keming Yu, Yiming Ye, Zidong Chen, Yangfan Yang, Jiangang Xu, and Iok Tong Chong
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medicine.medical_specialty ,Corvis ST ,genetic structures ,Scheimpflug principle ,Biomedical Engineering ,Ocular hypertension ,Glaucoma ,corneal indentation device ,Article ,Cornea ,Ophthalmology ,Indentation ,medicine ,Humans ,Intraocular Pressure ,business.industry ,Healthy subjects ,Stiffness ,medicine.disease ,eye diseases ,Biomechanical Phenomena ,glaucoma ,Cross-Sectional Studies ,medicine.anatomical_structure ,ocular hypertension ,sense organs ,medicine.symptom ,corneal biomechanics ,business ,Glaucoma, Open-Angle - Abstract
Purpose To evaluate the ability of the new in vivo corneal indentation device (CID) to measure corneal biomechanical properties. Methods and Results In total, 186 eyes from 46 healthy subjects, 107 patients with primary open-angle glaucoma, and 33 patients with ocular hypertension were enrolled in a cross-sectional study. Measurements were performed using corneal visualization Scheimpflug technology (Corvis ST) and the CID. The deformation amplitude (DA), inward applanation time, inward applanation velocity (A1V), outward applanation time (A2T), outward applanation velocity (A2V), highest concavity time, DA ratio, max inverse radius (MIR), integrated radius, and stiffness parameter A1 were included as Corvis ST parameters, and stiffness and modulus were included as CID parameters. Associations between the Corvis ST and CID parameters and correlations between central corneal thickness and corneal biomechanical parameters were analyzed. The stiffness was significantly correlated with all the Corvis ST parameters (P < 0.05). The modulus was significantly correlated with the DA, A1V, A2T, A2V, highest concavity time, and MIR (P < 0.05). The DA, inward applanation time, A1V, A2T, A2V, DA ratio, MIR, integrated radius, and stiffness parameter A1 values and both CID-derived values were significantly correlated with central corneal thickness (P < 0.05). Conclusions Parameters derived from the CID and Corvis ST demonstrated agreement in the measurement of corneal biomechanical properties. The stiffness and modulus can characterize in vivo corneal biomechanical properties. Translational Relevance Agreeing with the Corvis ST regarding the assessment of corneal biomechanical properties, the CID can be a novel clinical tool for biomechanical evaluation of the cornea.
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- 2021
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30. A novel dynamic random-dot stereopsis assessment to measure stereopsis in intermittent exotropia
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Junpeng Yuan, Jing Zhong, Zidong Chen, Jinrong Li, Minbin Yu, Daming Deng, and Lei Feng
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medicine.medical_specialty ,Stereopsis ,business.industry ,Ophthalmology ,Assessment methods ,Evaluation methods ,medicine ,Original Article ,General Medicine ,business ,Strabismus ,Intermittent exotropia ,Disease course - Abstract
BACKGROUND: To investigate dynamic stereopsis in intermittent exotropia [X(T)] patients using a novel dynamic random-dot stereopsis assessment method. METHODS: A novel dynamic random-dot stereopsis test was performed using novel self-programmed software, which consisted of red and green dots and four blocks on the screen. The test included motion + disparity (MD), motion (M), and disparity (D), where the D cues ranged from 200 to 1,200 arc-seconds. The characteristics of preoperative dynamic stereopsis in 83 X(T) patients and associations with clinical features were analysed, and the prognosis was followed up on the 1(st) day and at the 2(nd), 6(th) and 12(th) months postoperatively. RESULTS: Preoperatively, the mean reciprocal values of near and far stereopsis were 0.013±0.0016 and 0.0011±0.0005 arc-seconds in static stereopsis patients, respectively, and the MD, M, and D values were 0.002±0.0002, 0.0018±0.0001, and 0.0012±0.0002 arc-seconds in dynamic stereopsis, respectively. The MD value was negatively correlated with the Newcastle control score, disease course, and prism deviations (P
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- 2021
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31. Evaluation of dynamic stereopsis in intermittent exotropia patients
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Junpeng Yuan, Daming Deng, Lei Feng, Zidong Chen, Jing Zhong, Jinrong Li, Minbin Yu, and Ai-Hou Wang
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Reproducibility ,medicine.medical_specialty ,Stereoblindness ,business.industry ,Bagolini striated lens test ,intermittent exotropia ,Normal group ,Disease course ,Ophthalmology ,Stereopsis ,disparity ,lcsh:Ophthalmology ,lcsh:RE1-994 ,Clinical Research ,motion ,Medicine ,business ,Intermittent exotropia - Abstract
AIM: To delineate the characteristics of the dynamic stereopsis test and analyze related parameters in intermittent exotropia [X(T)] patients. METHODS: Fifty-seven X(T) patients and 55 normal subjects were enrolled in this study. The normal and X(T) groups were used to test the reproducibility and reliability of the dynamic stereopsis test, and Bangerter filters with densities of 0.2 were then used to simulate suppression to test for traditional and dynamic stereopsis. In the X(T) group, the measurements included 1) dynamic stereopsis test comprising three parts: motion+disparity, motion only and disparity only; 2) ocular deviation angle; 3) Bagolini striated lens test; 4) disease course; and 5) Titmus stereopsis test. RESULTS: The test-retest reliability of the dynamic stereopsis method was 0.901 in the normal and X(T) groups, and none of the X(T) patients were able to pass the static and dynamic stereopsis tests after using the 0.2 Bangerter filter. The accuracy rate was greater than 80% in the normal group and 31.81%, 36.36%, and 45.45% for the motion+disparity, motion-only and disparity-only components of the traditional test for X(T) patients diagnosed with stereoblindness via traditional tests, respectively. Patients with a long disease course (>1y) had worse dynamic stereopsis than those with a short disease course (0.05, Chi-square test). CONCLUSION: Dynamic stereopsis is preserved in certain X(T) patients diagnosed with stereoblindness via traditional tests. A long disease course was shown to be a negative factor for dynamic stereopsis in X(T) patients which might be associated with worse progression, and provide good references clinically.
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- 2019
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32. Contrast-balanced binocular treatment in children with deprivation amblyopia
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Benjamin Thompson, Junpeng Yuan, Shuan Dai, Zidong Chen, Lisa M Hamm, Jinrong Li, Joanna Black, and Minbin Yu
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medicine.medical_specialty ,Visual acuity ,genetic structures ,Adolescent ,Pseudophakia ,media_common.quotation_subject ,Visual Acuity ,Subgroup analysis ,Cataract Extraction ,Amblyopia ,Cataract ,Developmental psychology ,Deprivation amblyopia ,Contrast Sensitivity ,03 medical and health sciences ,0302 clinical medicine ,Cataracts ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Strabismic amblyopia ,Contrast (vision) ,Humans ,Prospective Studies ,Child ,media_common ,Vision, Binocular ,business.industry ,Treatment options ,Infant ,Childhood cataract ,medicine.disease ,eye diseases ,Eyeglasses ,Child, Preschool ,030221 ophthalmology & optometry ,medicine.symptom ,Sensory Deprivation ,business ,030217 neurology & neurosurgery ,Optometry ,Follow-Up Studies - Abstract
Background Children with deprivation amblyopia due to childhood cataract have been excluded from much of the emerging research into amblyopia treatment. An investigation was conducted to determine whether contrast-balanced binocular treatment - a strategy currently being explored for children with anisometropic and strabismic amblyopia - may be effective in children with deprivation amblyopia. Methods An unmasked, case-series design intended to assess proof of principle was employed. Eighteen children with deprivation amblyopia due to childhood cataracts (early bilateral n = 7, early unilateral n = 7, developmental n = 4), as well as 10 children with anisometropic (n = 8) or mixed anisometropic and strabismic amblyopia (n = 2) were prescribed one hour a day of treatment over a six-week period. Supervised treatment was available. Visual acuity, contrast sensitivity, global motion perception and interocular suppression were measured pre- and post-treatment. Results Visual acuity improvements occurred in the anisometropic/strabismic group (0.15 ± 0.05 logMAR, p = 0.014), but contrast sensitivity did not change. As a group, children with deprivation amblyopia had a smaller but statistically significant improvement in weaker eye visual acuity (0.09 ± 0.03 logMAR, p = 0.004), as well a significant improvement in weaker eye contrast sensitivity (p = 0.004). Subgroup analysis suggested that the children with early bilateral deprivation had the largest improvements, while children with early unilateral cataract did not improve. Interestingly, binocular contrast sensitivity also improved in children with early bilateral deprivation. Global motion perception improved for both subgroups with early visual deprivation, as well as children with anisometropic or mixed anisometropic/strabismic amblyopia. Interocular suppression improved for all subgroups except children with early unilateral deprivation. Conclusion These data suggest that supervised contrast-balanced binocular treatment should be further investigated as a treatment option for children with deprivation amblyopia. However, for children with more severe deprivation amblyopia due to early unilateral cataracts, supplementary or alternative options should also be explored.
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- 2017
33. Objective Assessment of the Effect of Optical Treatment on Magnocellular and Parvocellular-biased Visual Response in Anisometropic Amblyopia
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Zitian Liu, Zidong Chen, Ying Han, Minbin Yu, Junpeng Yuan, Yunzhi Xu, Daming Deng, and Lei Feng
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Adult ,Male ,medicine.medical_specialty ,Visual acuity ,Adolescent ,genetic structures ,media_common.quotation_subject ,Visual Acuity ,Visual Physiology ,Visual system ,Amblyopia ,optical treatment ,Objective assessment ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Parvocellular cell ,Ophthalmology ,visual plasticity ,medicine ,Humans ,Contrast (vision) ,Visual Pathways ,visual pathway ,media_common ,Eye Movements, Strabismus, Amblyopia and Neuro-Ophthalmology ,business.industry ,eye diseases ,Electrophysiology ,Eyeglasses ,nervous system ,Case-Control Studies ,030221 ophthalmology & optometry ,Evoked Potentials, Visual ,Significant response ,Female ,sense organs ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
Purpose Optical treatment can improve visual function in anisometropic amblyopia, but there is no electrophysiological evidence, and the underlying change in visual pathway remains unknown. Our aims were to characterize the functional loss in magnocellular and parvocellular visual pathways in anisometropic amblyopia at baseline and to investigate the effect of optical treatment on the 2 visual pathways. Methods Using isolated-check visual-evoked potential, we measured the magnocellular- and parvocellular-biased contrast response functions in 15 normal controls (20.13 ± 3.93 years; mean ± standard deviation), 16 patients with anisometropic amblyopia (18.00 ± 6.04 years) who were fully refractive corrected before and 29 (19.41 ± 7.41 years) who had never been corrected. Twelve previously uncorrected amblyopes received optical treatment for more than 2 months and finished the follow-up measurement. Results Both the magnocellular- and parvocellular-biased contrast response functions in the amblyopic eye exhibited significantly reduced response and weaker contrast gains. We also found that the uncorrected amblyopes showed a more severe response reduction in magnocellular-biased, but not parvocellular-biased condition when compared with those corrected, with a weaker initial contrast gain and lower maximal response. After optical treatment, 12 uncorrected amblyopes demonstrated improved visual acuity of the amblyopic eye and a significant response gain to magnocellular-biased but not parvocellular-biased stimuli. Conclusions We demonstrated deficits to both magnocellular- and parvocellular-biased stimuli in subjects with anisometropic amblyopia. Optical treatment could produce neurophysiological changes in visual pathways even in older children and adults, which may be mediated through the magnocellular pathway.
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- 2020
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34. Anisometropic Amblyopia: Interocular Contrast and Viewing Luminance Effects on Aniseikonia
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Junpeng Yuan, Daming Deng, Minbin Yu, Lei Feng, Jinrong Li, Xiaoxiao Cai, Jing Liu, and Zidong Chen
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aniseikonia ,Vision, Binocular ,medicine.medical_specialty ,genetic structures ,luminance ,business.industry ,anisometropic amblyopia ,media_common.quotation_subject ,Optical correction ,Aniseikonia ,Biomedical Engineering ,Amblyopia ,contrast ,Luminance ,Article ,eye diseases ,Ophthalmology ,medicine ,Humans ,Contrast (vision) ,In patient ,business ,media_common - Abstract
Purpose To demonstrate an aniseikonia test for anisometropic amblyopia (ATAA) that uses variable viewing luminance at different interocular contrast levels. Methods The test consists of a direct size comparison task based on a computer. The subject is asked to adjust the size of a dichoptically dissociated paired square target. One square was always presented at 100% contrast to the amblyopic eye/nondominant eye, whereas its counterpart was presented to the fellow eye at six contrast levels. Measurements were performed at two luminance backgrounds: (1) a white square on a black background (WoB) and (2) a black square on a white background (BoW). To test the feasibility of this approach, 16 patients with anisometropic amblyopia and 23 normal controls were recruited. Results The Aniseikonia Index (AI) calculated from the ATAA increased when the difference in the interocular contrast increased in both the patients with anisometropic amblyopia and controls under BoW and WoB conditions. The mean AI differed dramatically between the BoW and WoB conditions in patients with amblyopia but not in normal subjects. Conclusions Our model predicted interocular differences in contrast to the measurement of aniseikonia. Execution of the AI in individuals with amblyopia should consider that their responses to different luminance viewing conditions could be asymmetric. Translational relevance The ATAA has the potential to optimize optical correction for the management of aniseikonia in individuals with anisometropic amblyopia.
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- 2020
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35. Effects of Monocular Perceptual Learning on Binocular Visual Processing in Adolescent and Adult Amblyopia
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Minbin Yu, Jin Yuan, Zidong Chen, Zhonghao Wang, Siyuan Deng, Xuan Qiu, Li Gu, Xiang Wu, Zhong-Lin Lu, Lei Feng, Jianhua Yan, Zhipeng Chen, and Jinrong Li
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0301 basic medicine ,medicine.medical_specialty ,genetic structures ,Behavioral testing ,02 engineering and technology ,Significant negative correlation ,Behavioral neuroscience ,Audiology ,Article ,Sensory neuroscience ,Visual processing ,Behavioral Neuroscience ,03 medical and health sciences ,Perceptual learning ,medicine ,lcsh:Science ,Biological sciences ,Multidisciplinary ,Monocular ,Biological Sciences ,021001 nanoscience & nanotechnology ,eye diseases ,030104 developmental biology ,lcsh:Q ,sense organs ,Sensory Neuroscience ,0210 nano-technology ,Psychology - Abstract
Summary Re-establishing normal binocular visual processing is the key to amblyopia recovery beyond the critical period of visual development. Here, by combining perceptual learning, behavioral testing, and steady-state visually evoked potentials (SSVEPs), we examined how monocular perceptual learning in the amblyopic eye could change binocular visual processing in the adolescent and adult amblyopic visual system. We found that training reduced the interocular difference between amblyopic and fellow eyes and increased the amplitude of a binocular SSVEP component, with a significant negative correlation between the two measures. Our results demonstrate that training in the amblyopic eye primarily improves binocular rather than monocular visual processing in the amblyopic visual system, suggesting that behavioral training could potentially address key neural deficits in adolescent and adult amblyopia., Graphical Abstract, Highlights • PL reduced the interocular difference • PL increased the amplitude of a binocular SSVEP component • Training in the amblyopic eye improves binocular visual processing, Biological Sciences; Behavioral Neuroscience; Sensory Neuroscience
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- 2020
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36. The Effect of Bangerter Filters on Binocular Function in Observers With Amblyopia
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Robert F. Hess, Lily Y.L. Chan, Minbin Yu, Daming Deng, Zidong Chen, Jinrong Li, Junpeng Yuan, and Benjamin Thompson
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Adult ,Male ,medicine.medical_specialty ,Visual acuity ,Adolescent ,genetic structures ,Binocular summation ,Visual Acuity ,Amblyopia ,Binocular function ,Ocular dominance ,Young Adult ,Cellular and Molecular Neuroscience ,Ophthalmology ,Psychophysics ,medicine ,Humans ,Child ,Vision, Binocular ,Monocular ,business.industry ,Equipment Design ,eye diseases ,Sensory Systems ,Eyeglasses ,Female ,Spatial frequency ,medicine.symptom ,business ,Binocular vision - Abstract
Purpose We assessed whether partial occlusion of the nonamblyopic eye with Bangerter filters can immediately reduce suppression and promote binocular summation of contrast in observers with amblyopia. Methods In Experiment 1, suppression was measured for 22 observers (mean age, 20 years; range, 14-32 years; 10 females) with strabismic or anisometropic amblyopia and 10 controls using our previously established "balance point" protocol. Measurements were made at baseline and with 0.6-, 0.4-, and 0.2-strength Bangerter filters placed over the nonamblyopic/dominant eye. In Experiment 2, psychophysical measurements of contrast sensitivity were made under binocular and monocular viewing conditions for 25 observers with anisometropic amblyopia (mean age, 17 years; range, 11-28 years; 14 females) and 22 controls (mean age, 24 years; range, 22-27; 12 female). Measurements were made at baseline, and with 0.4- and 0.2-strength Bangerter filters placed over the nonamblyopic/dominant eye. Binocular summation ratios (BSRs) were calculated at baseline and with Bangerter filters in place. Results Experiment 1: Bangerter filters reduced suppression in observers with amblyopia and induced suppression in controls (P = 0.025). The 0.2-strength filter eliminated suppression in observers with amblyopia and this was not a visual acuity effect. Experiment 2: Bangerter filters were able to induce normal levels of binocular contrast summation in the group of observers with anisometropic amblyopia for a stimulus with a spatial frequency of 3 cycles per degree (cpd, P = 0.006). The filters reduced binocular summation in controls. Conclusions Bangerter filters can immediately reduce suppression and promote binocular summation for mid/low spatial frequencies in observers with amblyopia.
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- 2014
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37. Phakic posterior chamber intraocular lens for unilateral high myopic amblyopia in Chinese pediatric patients
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Jing Zhang, Minbin Yu, Jinrong Li, Keming Yu, and Zidong Chen
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medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,medicine.medical_treatment ,media_common.quotation_subject ,Phakic intraocular lens ,03 medical and health sciences ,0302 clinical medicine ,Clinical Research ,Ophthalmology ,Refractive surgery ,medicine ,Contrast (vision) ,Anisometropia ,media_common ,business.industry ,Stereopsis recovery ,medicine.disease ,eye diseases ,030221 ophthalmology & optometry ,medicine.symptom ,business ,Phakic posterior chamber intraocular lens ,030217 neurology & neurosurgery - Abstract
Aim To assess the outcomes of posterior chamber implantable collamer lens (ICL) implantation in Chinese pediatric patients with unilateral high myopic amblyopia. Methods Eleven eyes of 11 amblyopic patients aged 11.02±3.34y underwent ICL (model V4, Staar Surgical Inc.) implantation to treat unilateral anisometropia were studied. Visual acuity, cycloplegic refraction, contrast sensitivity, stereopsis, intraocular pressure (IOP), vaulting, corneal endothelial cell count and complications were evaluated. Patients completed follow-up at 3d, 1, 3mo and the last follow-up time (mean 8.18±2.82mo) after surgery. Results The mean myopic anisometropia was -13.70±3.25 D preoperatively and +0.69±2.63 D at 8mo postoperatively. The logMAR corrected distance visual acuity (CDVA) of the amblyopic eye was 1.51±0.72 preoperatively and 0.75±0.40 at 8mo postoperatively. The logMAR CDVA at 3d, 1, 3 and 8mo postoperatively improved by a mean of 0.64, 1.55, 1.82 and 2.64 lines and gained more than 2 lines accounted for 18%, 45%, 45%, 64%, respectively. The contrast sensitivity of 0.5, 1 and 2 cpd in amblyopic eyes was significantly increased after surgery. No patient had near stereopsis recovery. The vaulting at 3 and 8mo was significantly lower than that at 1mo postoperatively. No other intraoperative or postoperative complications were observed, except an acute pupillary block glaucoma happened in a patient at two weeks postoperatively. Conclusion This short-term results indicate that ICL implantation can be a promising alternative therapy for high myopic anisometropic amblyopia in pediatric patients who have failed with conventional treatments and not suitable to corneal refraction surgery.
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- 2016
38. Semiclassical methods to the Klein–Gordon equation with the unequal scalar and vector potentials
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Zidong Chen, Gang Chen, and Pei-cai Xuan
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Physics ,Scalar (mathematics) ,Semiclassical physics ,Scalar potential ,General Medicine ,Exponential function ,symbols.namesake ,Quantum mechanics ,Bound state ,symbols ,Coulomb ,Klein–Gordon equation ,Mathematical physics ,Vector potential - Abstract
When the scalar potential is larger than the vector potential there are very few exactly solvable Klein?Gordon equations. Based on a general transformation between the unequal scalar and vector potential, in this paper, we employ two semiclassical methods to determine the bound state energy spectrum of the Klein?Gordon equation. To illustrate this procedure, the scalar potentials are chosen as the linear, exponential and linear plus Coulomb potentials and the corresponding energy spectra are analytically obtained. It is shown that the energy spectrum can be obtained by a simple algebraic method and our proposal methods can be extended to discuss the quasi-exactly solvable cases.
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- 2006
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39. Quantum phase transition for the Dicke model with the dipole–dipole interactions
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Dingfeng Zhao, Gang Chen, and Zidong Chen
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Quantum optics ,Quantum phase transition ,Physics ,Dipole ,Phase transition ,Condensed matter physics ,Physics::Atomic Physics ,Condensed Matter Physics ,Ground state ,Scaling ,Atomic and Molecular Physics, and Optics ,Spectral line ,Excitation - Abstract
In this paper, we reveal a second-order phase transition for the Dicke model with the dipole–dipole interaction between the atoms. By means of Holstein–Primakoff transformation, the energy spectra for both the normal and superradiant phases are explicitly obtained and therefore the scaling behaviour near the critical transition point can be given clearly. It is also shown that the dipole–dipole interactions between the atoms deeply affect the critical transition point, the ground-state and excitation energies and the scaled atomic inversion in the ground state.
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- 2006
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40. Exactly solvable potentials of the Klein–Gordon equation with the supersymmetry method
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Gang Chen, Pei-cai Xuan, and Zidong Chen
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Physics ,symbols.namesake ,Screened Poisson equation ,Quantum mechanics ,Scalar (mathematics) ,symbols ,General Physics and Astronomy ,Relativistic wave equations ,Supersymmetric quantum mechanics ,Supersymmetry ,Klein–Gordon equation ,Mathematical physics ,Exponential function - Abstract
Based on a general relation between the vector and scalar potentials we construct a series of exactly solvable potentials for the one-dimensional Klein–Gordon equation by means of supersymmetry and shape-invariance approach. The exact solutions of Klein–Gordon equation with linear and exponential potentials are obtained explicitly as examples to explain our method.
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- 2006
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41. Wigner function of the position-dependent effective Schrödinger equation
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Zidong Chen and Gang Chen
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Physics ,Mass distribution ,Wigner quasiprobability distribution ,Wigner semicircle distribution ,Condensed Matter Physics ,Wave equation ,Atomic and Molecular Physics, and Optics ,Wigner D-matrix ,Schrödinger equation ,symbols.namesake ,Effective mass (solid-state physics) ,Quantum mechanics ,symbols ,Wigner distribution function ,Mathematical Physics ,Mathematical physics - Abstract
In this paper, we calculate the Wigner distribution function to reveal the quantum–classical connection for the Schrodinger equation with position-dependent effective mass. On mapping this wave equation into an isospectral one with constant mass, the Wigner distribution function, which can be used to calculate matrix elements and expectation values of operators, can be obtained analytically for a given mass distribution and potential function.
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- 2006
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42. Exact bound state solutions of the s-wave Klein–Gordon equation with the generalized Hulthén potential
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Gang Chen, Zidong Chen, and Zhi-Mei Lou
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Physics ,symbols.namesake ,S-wave ,Bound state ,symbols ,General Physics and Astronomy ,Scalar potential ,Klein–Gordon equation ,Vector potential ,Mathematical physics - Abstract
In this Letter, on the condition that the generalized Hulthen-type scalar potential is not less than its vector potential, the exact bound state solutions of the s-wave Klein–Gordon equation of the generalized Hulthen potential are obtained in terms of the super-symmetric quantum mechanics. The conclusions contain the standard Hulthen and Wood–Saxon potentials.
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- 2004
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43. Exact solutions of the position-dependent mass Schrödinger equation in D dimensions
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Gang Chen and Zidong Chen
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Physics ,Mass distribution ,General Physics and Astronomy ,Canonical transformation ,Wave equation ,Schrödinger equation ,symbols.namesake ,Effective mass (solid-state physics) ,Quantum mechanics ,Bound state ,symbols ,Wave function ,Harmonic oscillator ,Mathematical physics - Abstract
In this Letter, we employ the point canonical transformation to solve the D-dimensional position-dependent effective mass Schrodinger equation with physical potentials. By mapping this wave equation into the well-known exactly solvable D-dimensional Schrodinger equation with constant mass, for a given spatial dependent mass distribution, the exact bound state solutions including the energy spectrum and corresponding wave functions are derived. As examples, the cases of the harmonic oscillator and Coulomb potential are considered.
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- 2004
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44. Motion-generated optical information allows event perception despite blurry vision in AMD and amblyopic patients
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Shirin E Hassan, Xiaoye Michael Wang, Hongyuan Wu, Emily A. Mangiaracina, Jing Samantha Pan, Christopher Connell, Zidong Chen, Geoffrey P. Bingham, and Jingrong Li
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Male ,Computer science ,media_common.quotation_subject ,Motion Perception ,Vision, Low ,Optic Flow ,Amblyopia ,050105 experimental psychology ,Motion (physics) ,Macular Degeneration ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Static image ,Perception ,Humans ,0501 psychology and cognitive sciences ,Event perception ,Computer vision ,Motion perception ,Aged ,media_common ,Aged, 80 and over ,Analysis of Variance ,business.industry ,05 social sciences ,Sensory Systems ,Ophthalmology ,Flow (mathematics) ,Blurry vision ,Case-Control Studies ,030221 ophthalmology & optometry ,Female ,Spatial frequency ,Artificial intelligence ,business - Abstract
Events consist of objects in motion. When objects move, their opaque surfaces reflect light and produce both static image structure and dynamic optic flow. The static and dynamic optical information co-specify events. Patients with age-related macular degeneration (AMD) and amblyopia cannot identify static objects because of weakened image structure. However, optic flow is detectable despite blurry vision because visual motion measurement uses low spatial frequencies. When motion ceases, image structure persists and might preserve properties specified by optic flow. We tested whether optic flow and image structure interact to allow event perception with poor static vision. AMD (Experiment 1), amblyopic (Experiments 2 and 3), and normally sighted observers identified common events from either blurry (Experiments 1 and 2) or clear images (Experiment 3), when either single image frames were presented, a sequence of frames was presented with motion masks, or a sequence of frames was presented with detectable motion. Results showed that with static images, but no motion, events were not perceived well by participants other than controls in Experiment 3. However, with detectable motion, events were perceived. Immediately following this and again after five days, participants were able to identify events from the original static images. So, when image structure information is weak, optic flow compensates for it and enables event perception. Furthermore, weakened static image structure information nevertheless preserves information that was once available in optic flow. The combination is powerful and allows events to be perceived accurately and stably despite blurry vision.
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- 2017
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45. Dichoptic training improves contrast sensitivity in adults with amblyopia
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Lily Y.L. Chan, Jinrong Li, Zidong Chen, Benjamin Thompson, Robert F. Hess, Minbin Yu, Daming Deng, and Daniel P. Spiegel
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Adult ,Male ,medicine.medical_specialty ,genetic structures ,medicine.medical_treatment ,media_common.quotation_subject ,education ,Visual Acuity ,Audiology ,Amblyopia ,Contrast Sensitivity ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Perceptual learning ,Vision, Monocular ,medicine ,Contrast (vision) ,Humans ,Video game ,media_common ,Communication ,Depth Perception ,Vision, Binocular ,Monocular ,Transcranial direct-current stimulation ,business.industry ,Reproducibility of Results ,eye diseases ,Sensory Systems ,Ophthalmology ,Visual cortex ,medicine.anatomical_structure ,Stereopsis ,Video Games ,030221 ophthalmology & optometry ,Female ,business ,Psychology ,Binocular vision ,030217 neurology & neurosurgery ,Photic Stimulation - Abstract
Dichoptic training is designed to promote binocular vision in patients with amblyopia. Initial studies have found that the training effects transfer to both binocular (stereopsis) and monocular (recognition acuity) visual functions. The aim of this study was to assess whether dichoptic training effects also transfer to contrast sensitivity (CS) in adults with amblyopia. We analyzed CS data from 30 adults who had taken part in one of two previous dichoptic training studies and assessed whether the changes in CS exceeded the 95% confidence intervals for change based on test–retest data from a separate group of observers with amblyopia. CS was measured using Gabor patches (0.5, 3 and 10 cpd) before and after 10 days of dichoptic training. Training was delivered using a dichoptic video game viewed through video goggles (n = 15) or on an iPod touch equipped with a lenticular overlay screen (n = 15). In the iPod touch study, training was combined with anodal transcranial direct current stimulation of the visual cortex. We found that dichoptic training significantly improved CS across all spatial frequencies tested for both groups. These results suggest that dichoptic training modifies the sensitivity of the neural systems that underpin monocular CS.
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- 2014
46. Spatial and Global Sensory Suppression Mapping Encompassing the Central 10° Field in Anisometropic Amblyopia
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Junpeng Yuan, Minbin Yu, Jing Liu, Zidong Chen, Jinrong Li, Xiaoxiao Cai, Daming Deng, and Jingjing Li
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Adult ,Male ,medicine.medical_specialty ,Visual acuity ,Adolescent ,genetic structures ,Sensory system ,Audiology ,Amblyopia ,Luminance ,Anisometropia ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Psychophysics ,Humans ,In patient ,Mathematics ,Depth Perception ,Vision, Binocular ,eye diseases ,Visual field ,Sensory Thresholds ,030221 ophthalmology & optometry ,Female ,Sensory Deprivation ,Visual Fields ,medicine.symptom ,Neutral density filter ,Photic Stimulation ,030217 neurology & neurosurgery ,Coherence (physics) - Abstract
Purpose We investigate the efficacy of a novel dichoptic mapping paradigm in evaluating visual function of anisometropic amblyopes. Methods Using standard clinical measures of visual function (visual acuity, stereo acuity, Bagolini lenses, and neutral density filters) and a novel quantitative mapping technique, 26 patients with anisometropic amblyopia (mean age = 19.15 ± 4.42 years) were assessed. Two additional psychophysical interocular suppression measurements were tested with dichoptic global motion coherence and binocular phase combination tasks. Luminance reduction was achieved by placing neutral density filters in front of the normal eye. Results Our study revealed that suppression changes across the central 10° visual field by mean luminance modulation in amblyopes as well as normal controls. Using simulation and an elimination of interocular suppression, we identified a novel method to effectively reflect the distribution of suppression in anisometropic amblyopia. Additionally, the new quantitative mapping technique was in good agreement with conventional clinical measures, such as interocular acuity difference (P < 0.001) and stereo acuity (P = 0.005). There was a good consistency between the results of interocular suppression with dichoptic mapping paradigm and the results of the other two psychophysical methods (suppression mapping versus binocular phase combination, P < 0.001; suppression mapping versus global motion coherence, P = 0.005). Conclusions The dichoptic suppression mapping technique is an effective method to represent impaired visual function in patients with anisometropic amblyopia. It offers a potential in "micro-"antisuppression mapping tests and therapies for amblyopia.
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- 2017
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47. Simulation of the superradiant quantum phase transition in the superconducting charge qubits inside a cavity
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Zidong Chen, Gang Chen, and Jiu-Qing Liang
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Quantum phase transition ,Physics ,Phase transition ,Superradiant phase transition ,Photon ,Condensed matter physics ,Qubit ,Physics::Optics ,Charge (physics) ,Superradiance ,Superconducting quantum computing ,Atomic and Molecular Physics, and Optics - Abstract
In this paper, we propose an experimentally feasible scheme that the superconducting quantum interference devices are coupled with a high-quality cavity supporting a single-mode photon, to realize an effective Dicke model. By using several hundred artificial two-level atoms, the strong coupling regime can be successfully achieved. Moreover, in our proposal the superradiant phase transition for this model can be well controlled by the frequency of external magnetic flux when the superconducting charge qubits work at their optimal point, in which the qubits can be mostly immune from charge noise produced by uncontrollable charge fluctuations. Finally, we propose to observe this phase transition by detecting the intracavity intensity in terms of a heterodyne detector out of the cavity.
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- 2007
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48. Quantum tunneling in the adiabatic Dicke model
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Jiu-Qing Liang, Zidong Chen, and Gang Chen
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Physics ,Phase transition ,Instanton ,Condensed matter physics ,Quantum mechanics ,Degenerate energy levels ,Bosonic field ,Quantum entanglement ,Quantum field theory ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Coupling (probability) ,Atomic and Molecular Physics, and Optics ,Quantum tunnelling - Abstract
The Dicke model describes $N$ two-level atoms interacting with a single-mode bosonic field and exhibits a second-order phase transition from the normal to the superradiant phase. The energy levels are not degenerate in the normal phase but have degeneracy in the superradiant phase, where quantum tunneling occurs. By means of the Born-Oppenheimer approximation and the instanton method in quantum field theory, the tunneling splitting, inversely proportional to the tunneling rate for the adiabatic Dicke model, in the superradiant phase can be evaluated explicitly. It is shown that the tunneling splitting vanishes as $\mathrm{exp}(\ensuremath{-}N)$ for large $N$, whereas for small $N$ it disappears as $\sqrt{N}∕\mathrm{exp}(N)$. The dependence of the tunneling splitting on the relevant parameters, especially on the atom-field coupling strength, is also discussed.
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- 2007
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49. One-step generation of cluster states in superconducting charge qubits coupled with a nanomechanical resonator
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Lixian Yu, Zidong Chen, Gang Chen, and Jiu-Qing Liang
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Physics ,Cluster state ,Quantum mechanics ,Operator (physics) ,Qubit ,Charge (physics) ,Quantum entanglement ,Unitary operator ,W state ,Superconducting quantum computing ,Atomic and Molecular Physics, and Optics - Abstract
We present a scalable solid-state system in which the superconducting charge qubits are coupled with a nanomechanical resonator (NAMR) to achieve highly entangled cluster states, which are responsible for one-way quantum computing via single-qubit measurements. Since the NAMR can play the essential role of the data bus, the long-range interactions among the qubits can occur. Therefore, without using the interacting picture we can directly obtain the long-range Ising-like unitary operator U{sub z}({lambda})=exp[i{lambda}S{sub z}{sup 2}] with S{sub z} the collective spin operator in z direction and {lambda} a parameter, which is insensitive to the thermal state of the NAMR. Based on this unitary operator, a set of highly entangled cluster states can be produced by efficient one-step generation. Moreover, the robustness of the highly entangled cluster states with respect to unavoidable parameter variations is also demonstrated.
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- 2007
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50. Series Solutions of theN-Dimensional Effective-Mass Schrödinger Equation with the Power Law Potential
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Zidong Chen and Gang Chen
- Subjects
Physics ,Condensed Matter Physics ,Power law ,Atomic and Molecular Physics, and Optics ,Schrödinger equation ,symbols.namesake ,Gravitational potential ,Classical mechanics ,Effective mass (solid-state physics) ,Bound state ,symbols ,Electric potential ,Series expansion ,Mathematical Physics ,Harmonic oscillator - Abstract
In this paper the N-dimensional Schrodinger equation with position-dependent effective mass for any physical potential is derived. As an example, the analytical bound state solutions of the power law potential with the position dependent mass are obtained by series expansion method. The special cases of the Coulomb potential and the harmonic oscillator are discussed.
- Published
- 2005
- Full Text
- View/download PDF
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