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Quantifying peripapillary vessel density and retinal nerve fibre layer in type 1 diabetic children without clinically detectable retinopathy using OCTA

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 278-281页

作者： ling Chen Yun Feng Sha-Sha Zhang yan-Fang Liu ping lin Xi’an Children’s Hospital Affiliated to Xi’an Jiaotong University Xi’an 710002Shaanxi ProvinceChina

AIM:To quantify changes in radial peripapillary capillary vessel density(ppVD)and the peripapillary retinal nerve fiber layer(pRNFL)in children with type 1 diabetes without clinical diabetic retinopathy by optical coherence tomography angiography(OCTA),providing a basis for early retinopathy in children with type 1 ***:This was a retrospective study.A total of 30 patients(3–14y)with type 1 diabetes without clinical diabetic retinopathy(NDR group)were included.A total of 30 age-matched healthy subjects were included as the normal control group(CON group).The HbA1c level in the last 3mo was measured once in the NDR *** pRNFL thickness and ppVD were automatically measured,and the mean pRNFL and ppVD were calculated in the nasal,inferior,temporal,and superior *** changes in ppVD and pRNFL in the two groups were ***:Compared with CON group,the nasal and superior ppVDs decreased in the NDR group(all P0.05).Person and Spearman correlation analysis of ppVD and pRNFL thickness in each quadrant of the NDR group showed a positive correlation between nasal and superior(all P0.05).There was no significant correlation between the HbA1c level and ppVD and pRNFL in any quadrant(all P>0.05).There was no significant correlation between the course of diabetes mellitus and ppVD and pRNFL in any quadrant(all P>0.05).CONCLUSION:ppVD and pRNFL decrease in eyes of children with type 1 diabetes before clinically detectable retinopathy and OCTA is helpful for early monitoring.

关键词： diabetic retinopathy children peripapillary vessel density peripapillary retinal nerve fiber layer optical coherence tomography angiography

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Synthesis and characteristics of transparent Gd_(2)O_(3)ceramics with cubic structure

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Journal of Advanced Ceramics 2024年第4期13卷 463-468页

作者： Akio Ikesue yan lin Aung World Lab Co. Nagoya456-8587Japan

Transparent Gd_(2)O_(3)ceramics with a cubic crystal structure were successfully synthesized for the first *** Gd_(2)O_(3)ceramics subjected to hot isostatic press(HIP)at 1070℃consisted of uniform grains of 2-3μm,and only a few residual pores could be detected inside the materials.X-ray diffraction(XRD)shows that the obtained polycrystalline materials have a cubic crystal structure,and the transmission polarized light observation shows that there is no birefringence inside the materials,indicating inherent optical properties of the cubic crystal *** optical absorption edge is 640 nm(optical band gap:2.1 eV),and the transmittance in the visible to near-infrared region is 72%,which is close to the theoretical transmittance calculated from Fresnel *** constant of this material is almost wavelength-independent,and it is diamagnetic since it has the opposite polarity to that of common paramagnetic materials.

关键词： gadolinium oxide cubic hot isostatic press(HiP) diamagnetic Verdet constant

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Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks

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Digital Communications and Networks 2024年第1期10卷 109-116页

作者： Xiaoming He Yingchi Mao Yinqiu Liu ping ping yan Hong Han Hu The College of Computer and Information Hohai UniversityNanjingChina The Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing China The School of Computer Science and Engineering Nanyang Technological UniversitySingapore The College of Textile and Clothing Engineering Soochow UniversitySuzhouChina The College of Internet of Things Nanjing University of Posts and TelecomurunicationsNanjingChina

In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference ***,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable *** the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign ***,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power ***,agents in the collection stage slow down,which hinders the learning of other ***,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler *** experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods.

关键词： B5G Heterogeneous edge networks PPO Channel assignment Power allocation Throughput

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Flexible Crystal Heterojunctions of Low-Dimensional Organic Metal Halides Enabling Color-Tunable Space-Resolved Optical Waveguides

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Research 2024年第3期6卷 293-304页

作者： Yuhang lin Shuya Liu Dongpeng yan Beijing Key Laboratory of Energy Conversion and Storage Materials and Key Laboratory of RadiopharmaceuticalsMinistry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China.

Molecular luminescent materials with optical waveguide have wide application prospects in light-emitting diodes, sensors, and logic gates. However, the majority of traditional optical waveguide systems are based on brittle molecular crystals, which limited the fabrication, transportation, storage, and adaptation of flexible devices under diverse application situations. To date, the design and synthesis of photofunctional materials with high flexibility, novel optical waveguide, and multi-port color-tunable emission in the same solid-state system remain an open challenge. Here, we have constructed new types of zero-dimensional organic metal halides (Au-4-dimethylaminopyridine [DMAP] and In-DMAP) with a rarely high elasticity and rather low loss coefficients for optical waveguide. Theoretical calculations on the intermolecular interactions showed that the high elasticity of 2 molecular crystalline materials was original from their herringbone structure and slip plane. Based on one-dimensional flexible microrods of 2 crystals and the 2-dimensional microplate of the Mn-DMAP, heterojunctions with multi-color and space-resolved optical waveguides have been fabricated. The formation mechanism of heterojunctions is based on the surface selective growth on account of the low lattice mismatch ratio between contacting crystal planes. Therefore, this work describes the first attempt to the design of metal-halide-based crystal heterojunctions with high flexibility and optical waveguide, expanding the prospects of traditional luminescent materials for smart optical devices, such as logic gates and multiplexers.

关键词： waveguide Crystal elasticity

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EXTRAPOLATION AND A-POSTERIORI ERROR ESTIMATORS OF PETROV-GALERKIN METHODS FOR NON-linEAR VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2001年第4期19卷 407-422页

作者： Shu-hua Zhang (Department of Mathematical Sciences, University of Alberta, Edrmonton, Alberta, Canada T6G 2G1) Tao lin (Department of Mathematics, Virginia Tech, Blacksburg VA 24061) yan-ping lin (Department of Mathematical Sciences, University of Alberta University of Alberta 加拿大 T6G 2G1 Virginia Tech 美国 VA 24061 University of Alberta 加拿大 T6G 2G6

In this paper we will show that the Richardson extrapolation can be used to enhance the numerical solution generated by a Petrov-Galerkin finite element method for the initial value problem for a nonlinear Volterra integro-differential equation. As by-products, we will also show that these enhanced approximations can be used to form a class of posteriori estimators for this Petrov-Galerkin finite element method. Numerical examples are supplied to illustrate the theoretical results.

关键词： Volterra integro-differential equations Petrov-Galerkin finite element methods Asymptotic expansions Interpolation post-processing A-posteriori error estimators.

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Effect of pre-moxibustion on apoptosis and proliferation of gastric mucosa cells

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World Journal of Gastroenterology 2007年第15期13卷 2174-2178页

作者： Shou-Xiang Yi yan Peng Xiao-Rong Chang Na Peng Jie yan Yap-ping lin The Institute of Acupuncture Moxibustion and Massage Hunan University of Traditional Chinese Medicine Changsha 410007 Hunan Province China

AIM： TO observe the effects of pre-moxibustion on apoptosis and proliferation of gastric mucosal cell in rats with stress-induced ulcer, and to analyze the relationship between those effects and the expression of heat-shock protein 70 （HSP70）. METHODS： Sixty healthy Sprague Dawley rats were randomly assigned into four groups, namely group A, B, C and D. The animal model of stress ulcer was established by water immersion and restraint stress. The rats in group A, B, and D served as the restraint, model, and non-acupoint controls, respectively, while those in group C received moxibustion at Zusanli and Uangmen points. Immunohistochemical methodology was used to detect the expression of HSP70, apoptosis index （AI, × 10^-6/μm^2） and proliferation index （PCNA-LI, × 10^-6/μm^2）. The mucosal expression of transforming growth factor α （TGF-α） was detected by radioimmunoassay. RESULTS： IVloxibustion at Zusanli and Liangmen points significantly decreased the gastric injury and the apoptosis of gastric mucosal cells, while markedly increased the mucosal expression of TGF-α and HSP70 as well as the proliferation of gastric mucosal cells. Compared with group A, ulcer index （UI）（26.8 ± 9.8 vs 12.0 ± 5.9, P 〈 0.01）, AI （9.6 ± 4.2 vs 4.4 ± 2.6, P 〈 0.05） and expression of HSP70 （9.6 ± 4.2 vs 4.4 ± 2.6, P 〈 0.05） were significantly increased, but the content of TGF-α （104.7 ± 51.2 pg/mL vs 254.0 ± 86.9 pg/mL, P 〈 0.01） and PCNA-LI （6.9 ± 4.7 vs 14.9 ± 4.6, P 〈 0.05） were significantly decreased in group B. However, ulcer index values （UI） and AI were obviously lower in group C compared to groups B and D （14.1 ± 5.4 vs 26.8 ± 9.8 and 26.2 ± 7.7, P 〈 0.01, 3.0 ± 1.6 vs 9.6 ± 4.2 and 8.2 ± 5.2, P 〈0.05, respectively）, but content of TGF-α （237.0 ± 72.6 pg/mL vs 104.7 ± 51.2 pg/mL and 154.1 ± 61.3 pg/mL, P 〈0.01） and expression of HSP70 （0.13 ± 0.03 vs 0.08 ± 0.06 and 0.06 ± 0.04, P 〈 0.05） were higher in group C. Furthermore, the PCNA-LI was significantly higher in group C than in

关键词： Moxibustion Stress ulcer HSP70 Proliferating cell nuclear antigen Apoptosis

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Recent progress in diagnostic imaging and therapeutics of osteosarcoma based on multifunctional nanoparticles

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Science China Chemistry 2024年第9期67卷 2864-2889页

作者： Xueke yan Danmin lin Dingyuan yan Dong Wang Huifang Su Department of Orthopaedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Center for AIE Research College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China

Osteosarcoma is one of the most common primary bone malignancies,mainly occurring in children and *** diagnosis imaging methods for osteosarcoma contain X-ray,computed tomography and magnetic resonance imaging,and traditional therapy protocols are surgical resection and ***,these strategies are complicated and *** imaging methods,despite their maturity,have drawbacks that prevent them from showing more *** is more,the prognosis for patients with osteosarcoma remains unsatisfactory due to side effects of chemotherapy,as well as incomplete surgical removal of the *** compensate for the shortcomings of traditional imaging and treatment strategies for osteosarcoma,various types of nanoparticles have been designed and synthesized to selectively target osteosarcoma cells without toxic side effects on healthy *** the same time,these nanoparticle-based technologies can integrate the imaging and treatment of *** review summarizes the application of nanotechnology in the imaging and treatment of osteosarcoma in recent years,and finally discusses the challenges and development prospects,aiming to provide ideas for future research.

关键词： osteosarcoma nanotechnology imaging diagnosis therapy

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Holographic Polymer Nanocomposites with High Refractive Index Modulation by Doping Liquid Crystal E6M

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Chinese Journal of Polymer Science 2024年第7期42卷 926-935,I0006页

作者： Meng-Yun Wang Yue Zhang Dan Wang Ming Yao Yi-Xuan Wang Xing-ping Zhou Hai-yan Peng Xiao-lin Xie Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National Anti-counterfeit Engineering Research Center Huazhong University of Science and TechnologyWuhan430074China

Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield ***,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index ***,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer *** high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.

关键词： Polymer nanocomposites Holography AR/VR Refractive index modulation Liquid crystal

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A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： yan yan Guang-hao Shang Li-ping Zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

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Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan Zheng Jian-ping Zhou yan Xu Kai Li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

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