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Pars plana vitrectomy with internal limiting membrane plugging assisted by autologous blood for optic disc pit associated with vitreomacular traction

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1957-1959页

作者： Bin Chen Yan-ting Li Tian-Hong wu Ya-Ping Yuan Yun-feng Lu Department of Ophthalmology Suzhou EENT HospitalSuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

Dear Editor,We report a case of optic disc pit(ODP)associated with vitreomacular traction which has been successfully treated by a combined *** have obtained the written informed consent from the patient,and this case... 详细信息

关键词： technique. traction macular

A Hybrid Integrated and Low-Cost Multi-Chip Broadband Doherty Power Amplifier Module for 5G Massive MIMO Application

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Engineering 2024年第7期38卷 223-232页

作者： Fei Huang Guansheng Lv Huibo wu Wenhua Chen Zhenghe feng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabricated using the gallium arsenide(GaAs)integrated passive device(IPD)process,is proposed for 5G massive multiple-input multiple-output(MIMO)*** inverted DPA structure with a low-Q output network is proposed to achieve better bandwidth performance,and a single-driver architecture is adopted for a chip with high gain and small *** proposed DPA has a bandwidth of 4.4-5.0 GHz that can achieve a saturation of more than 45.0 *** gain compression from 37 dBm to saturation power is less than 4 dB,and the average power-added efficiency(PAE)is 36.3%with an 8.5 dB peak-to-average power ratio(PAPR)in 4.5-5.0 *** measured adjacent channel power ratio(ACPR)is better than50 dBc after digital predistortion(DPD),exhibiting satisfactory linearity.

关键词： 5G Doherty power amplifier Multi-input multi-output Multi-chip modules Hybrid integrated

A Piezoelectrically Driven Microrobot Using a Novel Monolithic Spatial Parallel Mechanism as Its Hip Joint

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Journal of Bionic Engineering 2024年第2期21卷 803-820页

作者： Guangping wu Ziyang Wang Jiaxin Zhao feng Cui Xinghan Cai National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai200240China Department of Micro-Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal *** microrobot uses a novel spatial parallel mechanism as its hip joint,which consists of two spatially orthogonal slider-crank *** mechanism maps two inputs of two independent actuators to the decoupled swing and lift outputs of a leg,and each leg can produce the closed trajectories in the sagittal plane necessary for robot ***,the kinematics of the transmission are analyzed,and the parameters of the flexure hinges are designed based on geometrical constraints and yield *** hip joints,legs and exoskeletons are integrated into a five-layer standard laminate for monolithic fabrication which is composed of two layers of carbon fiber,two layers of acrylic adhesive and a polyimide *** measured output force(15.97 mN)of each leg is enough to carry half of the robot’s weight,which is necessary for the robot to move *** has been proven that the robot can successfully perform forward and turning *** to the microrobot fabricated with discrete components,the monolithically fabricated microrobot is more capable of maintaining the original direction of locomotion when driven by a forward signal and has a greater speed,whose maximum speed is 25.05 cm/s.

关键词： Insect-like Crawling microrobot Piezoelectric drive Parallel mechanism Monolithic fabrication

Joint Transmit and Reflective Beamforming Design for Active IRS-Aided SWIPT Systems

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Chinese Journal of Electronics 2024年第2期33卷 536-548页

作者： Weiping SHI Qingqing wu Di wu feng SHU Jiangzhou WANG School of Electronic and Optical Engineering Nanjing University of Science and Technology Department of Electronic Engineering Shanghai Jiao Tong University School of Information and Communication Engineering Hainan University Department of Automation Shanghai Jiao Tong University School of Engineering University of Kent

To further improve the performance of passive intelligent reflecting surface(IRS)-assisted communication systems and mitigate the serious path loss due to “double-fading ” of IRS-assisted links, an active IRS-aided simultaneous wireless information and power transfer(SWIPT) system is investigated. This paper jointly optimizes the transmit beamforming at the base station(BS) and the phase shifts at the active IRS in order to maximize the power collected by the energy harvesting receiver under both perfect and imperfect channel state information(CSI)states, subject to the signal-to-interference-noise ratio constraint of the information decoding receiver, and the power constraints of the BS/IRS. Under perfect CSI, the alternating optimization algorithm is utilized for obtaining the transmit beamforming at the BS and the phase shifts at the active IRS. For each subproblem, we first transform nonconvex objective function and constraints into convex ones by performing a first-order Taylor expansion. Then, each subproblem is solved by using the interior point method. Given that obtaining perfect CSI is impractical, two robust beamforming designs are proposed for imperfect CSI case. Under the bounded CSI error model, we first transform the non-convex optimization problem into two semidefinite programming subproblems, and then solve each subproblem based on S-procedure and sequential rank-one constraint relaxation(SROCR) techniques. Under the stochastic CSI error model, the alternating optimization method is applied in an iterative manner based on Bernstein-type inequality and SROCR technique. Simulation results show that both robust and non-robust schemes for active IRS-assisted SWIPT systems can achieve extremely superior performance over conventional passive IRS-assisted systems under the same overall power budget.

关键词： Wireless communication Semidefinite programming Array signal processing Simulation Stochastic processes Transforms Receivers

Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China

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Journal of Integrative Agriculture 2024年第2期23卷 430-443页

作者： Zongyi wu Xiaolong feng Yumei Zhang Shenggen Fan Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China College of Economics and Management China Agricultural UniversityBeijing 100083China

China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable ***,the impact of this policy reform on food security and the environment remains inadequately ***,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high *** study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these *** the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental *** findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food *** fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic ***,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.

关键词： food security fertilizer manufacturing subsidies agri-food systems greenhouse gas emissions

Nonlinear proinflammatory effect of short-term PM_(2.5)exposure:A potential role of lipopolysaccharide

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Journal of Environmental Sciences 2024年第2期136卷 292-300页

作者： Fangxia Shen Mutong Niu Haoxuan Chen ting Zhang Jing Li Haijie Tong Yan wu School of Space and Environment Beihang UniversityBeijing 100191China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Institute of Surface Science Helmholtz-Zentrum HereonGeesthacht 21502Germany School of Environmental Science and Engineering Shandong UniversityJinan 250100China

The association between PM_(2.5)(particulate matter≤2.5μm)short-term exposure and its health effect is non-linear from the epidemiological *** this nonlinearity is suggested to be related with the PM_(2.5)heterogeneity,however,the underlying biological mechanism is still ***,a total of 38 PM_(2.5)filters were collected continuously for three weeks in winter Beijing,with the ambient PM_(2.5)varying between 10 and 270μg/m^(3).Human monocytes-derived macrophages(THP-1)were treated with PM_(2.5)water-soluble elutes at10μg/mL to investigate the PM_(2.5)short-term exposure effect from a proinflammatory *** proinflammatory cytokine tumor necrosis factor(TNF)induced by the PM_(2.5)elutes at equal concentrations were unequal,showing the heterogeneity of PM_(2.5)proinflammatory *** the various chemical and biological components,lipopolysaccharide(LPS)showed a strong positive association with the TNF ***,some outliers were observed among the TNF-LPS ***,for PM_(2.5)from relatively clean air episodes,the higher LPS amount corresponded to relatively low TNF *** this phenomenon was also observed in the promotion tests by treating macrophages with PM_(2.5)elutes dosed with additional trace *** expression analysis indicated the involvement of oxidative-stress related genes in the LPS signaling ***,a potential oxidative-stress-mediated suppression on the PM_(2.5)-borne LPS proinflammatory effect was proposed to be accounted for the ***,the results showed the differential role of LPS in the heterogeneity of PM_(2.5)proinflammatory effects from a component-based *** experimental studies are needed to elucidate the signaling pathway of LPS attached on PM_(2.5)from different air quality episodes.

关键词： Fine PM PM_(2.5)pro-inflammatory effects Aerosol health effect Endotoxin Oxidative stress

Do nocturnal birds use acoustic and visual cues to avoid predation by bats?

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Integrative Zoology 2024年第3期19卷 524-537页

作者： Lixin GONG Huan wu Zhiqiang WANG Hui wu Jiang feng tinglei JIANG Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchunChina Key Laboratory of Vegetation Ecology of Education Ministry Institute of Grassland ScienceNortheast Normal UniversityChangchunChina College of Life Science Jilin Agricultural UniversityChangchunChina

Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey *** an important defense strategy,sensory predator detection(such as through acoustic and visual cues)enables animals to assess predation risk and execute predator-avoidance behavior;however,there are limited studies on the anti-predation behavior of nocturnal *** prey of bats provides an excellent representative system for examining the anti-predation behavior of nocturnal ***,we broadcasted different types of echolocation calls of the bird-eating bat Ia io to two wild passerine birds,namely,Zosterops japonicus and Sinosuthora webbiana,that are preyed upon by ***,and presented the birds with individual bats under different light *** results showed that both bird species were able to perceive the low-frequency audible portion of the bats’echolocation calls;however,they did not exhibit escape responses to the acoustic *** the dark and under moonlit conditions,both bird species were unable to respond to active bats at close range and the birds only exhibited evasive flight behavior when bats approached or touched *** results suggest that nocturnal passerine birds may not be able to use acoustic or visual cues to detect bats and adopt evasive maneuvers to avoid *** work suggests that bat predation pressure may not elicit primary predator-avoidance responses in nocturnal passerine *** results provide new insights into the anti-predation behavior of nocturnal animals.

关键词： anti-predation behavior nocturnal animals sensory cues sensory defenses

Application of ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging in recurrent anastomotic tumors after surgery in digestive tract tumors

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2474-2483页

作者： Deng-feng Ge Hao Ren Zi-Chen Yang Shou-Xiang Zhao Zhen-ting Cheng Da-Da wu Bin Zhang Department of Cardiothoracic Surgery Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China

BACKGROUND This study was to investigate the application value of whole-body dynamic ^(18)F-fluorodeoxyglucose(FDG)positron emission tomography/computed tomogra-phy(PET/CT)imaging in recurrent anastomotic tumors of digestive tract after gastric and esophageal cancer *** patients with gastric and esophageal cancer have a high risk of tumor recurrence,and traditional imaging methods have certain limitations in early detection of recurrent ***-body dynamic ^(18)F-FDG PET/CT imaging,due to its high sensitivity and specifi-city,can provide comprehensive information on tumor metabolic activity,which is expected to improve the early diagnosis rate of postoperative recurrent tumors,and provide an important reference for clinical treatment *** A retrospective analysis was performed on 53 patients with upper digestive tract tumors after operation and systemic dynamic ^(18)F-FDG PET/CT imaging indi-cating abnormal FDG uptake by anastomosis,including 29 cases of gastric cancer and 24 cases of esophageal *** to the follow-up results of gas-troscopy and other imaging examinations before and after PET/CT examination,the patients were divided into an anastomotic recurrence group and anastomotic inflammation *** multi-parameter analysis software was used to obtain the metabolic rate(MRFDG),volume of distribution maximum(DVmax)of anastomotic lesions,and MRmean and DVmean of normal liver *** lesion/background ratio(LBR)was calculated by dividing the MRFDG and DVmax of the anastomotic lesion by the MRmean and DVmean of the normal liver tissue,respectively,to obtain LBR-MRFDG and *** independent sample t test was used for statistical analysis,and a receiver operating characteristic curve was used to analyze the differential diagnostic efficacy of each parameter for anastomotic recurrence and *** The dynamic ^(18)F-FDG PET/CT imaging parameters MRFDG,DVmax,LBR-MRFDG,and LBR-DVmax of post

关键词： Gastric cancer Esophageal cancer Anastomosis Dynamic positron emission tomography Differential diagnosis Metabolic rate

Strip flatness prediction of cold rolling based on ensemble methods

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Journal of Iron and Steel Research International 2024年第1期31卷 237-251页

作者： wu-quan Yang Zhi-ting Zhao Liang-yu Zhu Xun-yang Gao Li Wang School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142LiaoningChina

Aiming at the problem of insufficient prediction accuracy of strip flatness at the outlet of cold tandem rolling,the prediction performance of strip flatness based on different ensemble methods was studied and a high-precision prediction ensemble model of strip flatness at the outlet was ***,based on linear regression(LR),K nearest neighbors(KNN),support vector regression,regression trees(RT),and backpropagation neural network(BPN),bagging,boosting,and stacking ensemble methods were used for ensemble ***,three existing ensemble models,i.e.,random forest,extreme random tree(ET)and extreme gradient boosting,were used to conduct experiments and compare the *** research shows that bagging,boosting,and stacking three ensemble methods have the most significant improvement in the prediction accuracy of the regression trees model,which is increased by 5.28%,6.51%,and 5.32%,*** the same time,the stacking ensemble method improves both the simple model and the complex model,and the improvement effect on the simple base model is the greatest,which is 4.69%higher than that of the base model *** all of the ensemble models,the stacking ensemble model of level-1(ET,AdaBoost-RT,LR,BPN)paired with level-2(LR)was discovered to be the best model(EALB-LR)and can be further studied for industrial applications.

关键词： Tandem cold rolling Flatness prediction Machine learning Ensemble method