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On the Existence of Solutions for an Elliptic System of Equations with Arbitrary Order Growth

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 415-424页

作者： zhong-yuan liu Academy of Mathematics and Systems Science Chinese Academy of Sciences

Let BR be the ball centered at the origin with radius R in RN （N≥2）. In this paper we study the existence of solution for the following elliptic systemwhere λ 〉 0,μ 〉 0 p ≥ 2, q ≥ 2, u is the unit outward normal at the boundary OBR. Under certain assumptions on K（｜x｜）, using variational methods, we prove the existence of a positive and radially increasing solution for this problem without growth conditions on the nonlinearity.

关键词： elliptic system Nehari manifold variational method

Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-Di yuan Jun-Fa liu Bao-Liang zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

关键词： symptoms prevalence analysis

Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms

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Photonics Research 2024年第2期12卷 356-368页

作者： HUAN yuan ZHEQIANG zhong BIN ZHANG College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province Chengdu 610065China

Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing technologies.However,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and multifunctionality.In this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured metasurface.By controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image displays.In particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关键词： holographic asymmetric visible

High cerium content(Nd-Pr-Ce)_(2)Fe_(14)B melt-spun ribbons with high coercivity

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Journal of Rare Earths 2024年第4期42卷 690-695页

作者： Yujiang zhong Junming Wang Zikai yuan Ruijin liu Minggang Zhu Zhe liu Xin Chen Wei Li Zhaohui Guo Division of Functional Materials Central Iron and Steel Research InstituteBeijing100081China Ningbo Jinji Strong Magnetic Material Co. Ltd.Ningbo315172China Jiangxi Jiangwu Rare Metal New Material Co. Ltd.Nanchang330013China

The effects of wheel speeds on the magnetic properties and microstructures of[(Nd,Pr)_(1-x)Ce_(x)]-Fe-B meltspun ribbons were investigated.Compared to melt-spun ribbons with low cerium(Ce)content(x=0.2),amorphous formation can be suppressed at high wheel speed in the ribbons with a relatively high Ce content(x=0.8),and with the increase of the wheel speed,the magnetic properties of the ribbons with high Ce content raise continuously.At high wheel speed,the coercivity mechanism of melt-spun ribbons is mainly pinning field,and the high wheel speed introduces a large number of defects into the matrix as pinning sites.Furthermore,ribbons with high Ce content form a fine and uniform grain structure,so the grain boundary area enlarges,which further hinders the movement of domain walls.The combined effects of the above factors enable ribbons with high Ce content to have excellent magnetic properties(Hcj=0.977 T,Mr=64 m^(2) A/kg)at the wheel speed of 35 m/s.

关键词： Wheel speed Cecontent Microstructure Magnetic properties Rare earths

A 1-bp deletion in the MC04g1399 is highly associated with failure to produce fruit wart in bitter gourd

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Horticultural Plant Journal 2024年第1期10卷 171-180页

作者： Jia liu Junjie Cui Jichi Dong Jian zhong Chunfeng zhong Fanchong yuan Wendong Guan Fang Hu Jiaowen Cheng Kailin Hu College of Horticulture South China Agricultural UniversityGuangzhouGuangdong 510642China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China) Ministry of Agriculture and Rural AffairsGuangzhouGuangdong 510642China Guangdong Vegetables Engineering Research Center GuangzhouGuangdong 510642China Department of Horticulture Foshan UniversityFoshanGuangdong 528225China Henry Fok School of Biology and Agricultural Shaoguan UniversityShaoguanGuangdong 512023China

Fruit wart is an important appearance trait influencing consumer preferences of bitter gourd(Momordica charantia L.).The molecular genetic mechanisms underlying fruit wart formation in bitter gourd are largely unknown.In this study,genetic analysis based on four generations showed that fruit wart formation in bitter gourd was controlled by a single dominant locus named as Fwa.The Fwa locus was initially mapped into a 4.82 Mb region on pseudochromosome 4 by BSA-seq analysis and subsequently narrowed down to a 286.30 kb region by linkage analysis.A large F2population consisting of 2360 individuals was used to screen recombinants,and the Fwa locus was finally fine mapped into a 22.70 kb region harboring four protein-coding genes through recombination analysis.MC04g1399,encoding an epidermal patterning factor 2-like protein,was proposed as the best candidate gene for Fwa via sequence variation and expression analysis.In addition,a 1-bp insertion and deletion(InDel)variation within MC04g1399 was converted to a cleaved amplified polymorphic sequence(CAPS)marker that could precisely distinguish between the warty and non-warty types with an accuracy rate of 100%among a wide panel of 126 bitter gourd germplasm resources.Our results not only provide a scientific basis for deciphering the molecular mechanisms underlying fruit wart formation but also provide a powerful tool for efficient genetic improvement of fruit wart via marker-assisted selection.

关键词： Bitter gourd Fruit wart Bulk segregant analysis Fine-mapping Candidate gene

A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： zhong Qu Guoqing Mu Bin yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage space.This limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile devices.To solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature fusion.Firstly,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of images.In addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context information.Finally,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction map.We evaluate our method on three public crack datasets:DeepCrack,CFD,and Crack500.Experimental results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight crack detectionmodel,the parameter count of the mo

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

Predictability of the upper ocean heat content in a Community Earth System Model ensemble prediction system

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Acta Oceanologica Sinica 2024年第1期43卷 1-10页

作者： Ting liu Wenxiu zhong State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Atmospheric Sciences Sun Yat-Sen UniversityZhuhai 519082China

Upper ocean heat content(OHC)has been widely recognized as a crucial precursor to high-impact climate variability,especially for that being indispensable to the long-term memory of the ocean.Assessing the predictability of OHC using state-of-the-art climate models is invaluable for improving and advancing climate forecasts.Recently developed retrospective forecast experiments,based on a Community Earth System Model ensemble prediction system,offer a great opportunity to comprehensively explore OHC predictability.Our results indicate that the skill of actual OHC predictions varies across different oceans and diminishes as the lead time of prediction extends.The spatial distribution of the actual prediction skill closely resembles the corresponding persistence skill,indicating that the persistence of OHC serves as the primary predictive signal for its predictability.The decline in actual prediction skill is more pronounced in the Indian and Atlantic oceans than in the Pacific Ocean,particularly within tropical regions.Additionally,notable seasonal variations in the actual prediction skills across different oceans align well with the phase-locking features of OHC variability.The potential predictability of OHC generally surpasses the actual prediction skill at all lead times,highlighting significant room for improvement in current OHC predictions,especially for the North Indian Ocean and the Atlantic Ocean.Achieving such improvements necessitates a collaborative effort to enhance the quality of ocean observations,develop effective data assimilation methods,and reduce model bias.

关键词： ocean heat content prediction skill retrospective forecast experiment

Global adaptive output-feedback tracking with prescribed performance for uncertain nonlinear systems

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Science China(Information Sciences) 2024年第5期67卷 150-164页

作者： yuan WANG Yungang liu School of Control Science and Engineering Shandong University

At present, one typical control strategy for guaranteeing transient and steady-state performance is funnel control and prescribed performance control. The strategy features completely discarding the system nonlinearities, even if they are completely known and available. Such an intrinsic feature requires the controller to produce a larger control effect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we fully take advantage of known information on nonlinearities in control design, instead of completely discarding it as done in funnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of output feedback, tracking control, and the performance guarantee.As such, an adaptive output-feedback scheme is developed for global tracking with spatiotemporal performance specifications: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output feedback prescribed performance unknown control direction dynamic high gain global tracking

Immediate Effect of Electro-acupuncture on Endometrial Blood Flow in Patients with Recurrent Implantation Failure:A Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2024年第4期30卷 291-298页

作者： LAI yuan-yuan liu Li-ying WU Yong-na HUANG Lei ZHENG Xiao-yan GAN Di YU Si-yi zhong Ying LIANG Fan-rong ZHOU Ying YANG Jie Acupuncture and Tuina School Chengdu University of Traditional Chinese MedicineChengdu(610032)China Sichuan Jinxin Xi'nan Women's and Children's Hospital Chengdu(610032)China yuan TCM Wellness Pte.Ltd.(999002) Pulse TCM SingaporeSingapore

Objective To investigate the immediate effects of electro-acupuncture(EA)on endometrial blood flow among recurrent implantation failure(RIF)patients.Methods Eighty RIF patients,enrolled from March 2022 to December 2022,were randomly allocated into either the EA group(40 cases)or the waiting-list(WL)group(40 cases)by using a random number table.The EA group underwent acupuncture at points of Shenting(GV 24),Baihui(GV 4),Benshen(GB 13),bilateral Zigong(EX-CA 1),Huangshu(KI 16),Sanyinjiao(SP 6)and Xuehai(SP10),and electric acupuncture apparatus was connected to EX-CA 1,KI 16,SP 6,and SP 10 with disperse-dense waves at 4/20 Hz frequencies for 30 min after transvaginal ultrasound,while the WL group received no intervention.The primary outcome measured was the endometrial volume blood flow.The secondary outcomes included the bilateral uterine artery index,endometrial volume,endometrial blood flow type,vascular distribution index(VI^(MV))for endometrial and ovary,clinical pregnancy rate,and embryo implantation rate.Results In the EA group,there was a notable decrease in the bilateral pulsatility index and a significant improvement in the endometrial blood flow type post-EA(P0.05).Besides,no adverse events related to EA were observed.Conclusions EA can promptly ameliorate VI^(MV) for the endometrial and right ovary,and endometrial blood flow type.Future randomized controlled trials are warranted to investigate the long-term effects of EA on blood flow of RIF patients and its implications for pregnancy outcomes.(Trial registration No.ChiCTR2200057377).

关键词： electro-acupuncture recurrent implantation failure transvaginal ultrasound endometrial receptivityanalysis randomized controlledtrial