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Leave or Stay?Antecedents of High-level Talent Migration in the Pearl River Delta Megalopolis of China:from a Perspective of Regional Differentials in Housing Prices

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Chinese Geographical Science 2023年第6期33卷 1068-1081页

作者： SHEN Chen WANG Yang zuo jian Raufdeen RAMEEZDEEN School of Civil Engineering Wuhan UniversityWuhan430072China School of Architecture&Built Environment University of AdelaideAdelaide5005Australia School of Natural and Built Environments University of South AustraliaAdelaide5001Australia

Rapid urbanization and population growth have triggered an increase in urban housing demand and rising housing prices,which can influence the migration intention of high-level *** work within the literature has focused more on the migration of the general ***,antecedents of migration intention and the impact of housing prices on the migration of high-level talents remain ***,based on the push-pull theory,this study investigates the influencing factors of talent migration intention and explores the role of housing *** study reveals a complex mechanism underlying migration decisions by using logistic regression models and survey data of high-level talents in the Pearl River Delta(PRD)megalopolis of *** results indicate that:1)in high house-price regions,social integration is the primary push factor,and the main factors for retaining talents are the expectation of future work and intimate family relationships;2)in medium house-price regions,the main factors that attract talents are the current salary level and close family ties;3)in low house-price regions,living convenience is a determining factor in retaining *** study provides a new perspective for talent mobility research and offers valuable inputs for retaining and attracting talents in different economic development *** are of great significance for formulating talent introduction policies and forming a new pattern of rational spatial docking and effective allocation of human resources.

关键词： destination choice migration intention high-level talents house-price pressure push-pull theory the Pearl River Delta megalopolis of China

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An Improved UNet lightweight Network for Semantic Segmentation of Weed Images in Corn Fields

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Computers, Materials & Continua 2024年第6期79卷 4413-4431页

作者： Yu zuo Wenwen li School of Information and Control Engineering Jilin Institute of Chemical TechnologyJilin132022China School of Mechanical and Control Engineering Baicheng Normal UniversityBaicheng137000China

In cornfields,factors such as the similarity between corn seedlings and weeds and the blurring of plant edge details pose challenges to corn and weed *** addition,remote areas such as farmland are usually constrained by limited computational resources and limited collected ***,it becomes necessary to lighten the model to better adapt to complex cornfield scene,and make full use of the limited data *** this paper,we propose an improved image segmentation algorithm based on ***,the inverted residual structure is introduced into the contraction path to reduce the number of parameters in the training process and improve the feature extraction ability;secondly,the pyramid pooling module is introduced to enhance the network’s ability of acquiring contextual information as well as the ability of dealing with the small target loss problem;and lastly,Finally,to further enhance the segmentation capability of the model,the squeeze and excitation mechanism is introduced in the expansion *** used images of corn seedlings collected in the field and publicly available corn weed datasets to evaluate the improved *** improved model has a total parameter of 3.79 M and miou can achieve 87.9%.The fps on a single 3050 ti video card is about *** experimental results show that the network proposed in this paper can quickly segment corn weeds in a cornfield scenario with good segmentation accuracy.

关键词： Semantic segmentation deep learning UNet pyramid pooling module

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Expression of a novel dipeptidyl peptidase 8(DPP8)transcript variant,DPP8-v3,in human testis

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Asian Journal of Andrology 2005年第3期7卷 245-255,页

作者： Hui Zhu zuo-Min Zhou li Lu Min Xu Hui Wang jian-Min li Jia-Hao Sha Key Laboratory of Reproductive Medicine Department of Histology and Embryology Nanjing Medical UniversityNanjing 210029 China

Aim： To investigate the role of a novel dipeptidyl peptidase 8 transcript variant （DPP8-v3） gene in testis development and/or spermatogenesis. Methods： A human testis cDNA microarray was hybridized with mRNA of human adult and fetal testes. Differentially expressed clones were sequenced and characterized and their expression was analyzed by real-time reverse transcription polymerase chain reaction （RT-PCR） and Southern-blot analysis. Results： A new transcript variant of the human dipeptidyl peptidase （DPP8）, exhibiting a 5-fold higher expression level in human adult than that in fetal testes, was cloned and was named DPP8 variant 3 （DPP8-v3）. The full-length sequence of DPP8-v3 was 3,030 bp, encoding a protein of 898 amino acids. Conclusion： DPPS-v3 is a novel human DPP8 transcript variant highly expressed in the adult testis. Similar to DPPIV, DPP8-v3 may play a key role in the immunoregulation of testes and accordingly may influence spermatogenesis and male fertility. （Asian J Androl 2005 Sep; 7： 245-255）

关键词： DPP8 dipeptidyl peptidase IV (DPPIV) DPP8-v3 immunoregulation spermatogenesis testis

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纳米粒子在骨组织工程化基因修饰治疗中的应用

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中国组织工程研究 2025年第22期29卷 4771-4783页

作者：李光照裴锡波王剑口腔疾病防治全国重点实验室国家口腔医学中心国家口腔疾病临床医学研究中心四川大学华西口腔医院修复科四川省成都市610041

背景:传统的骨组织工程技术治疗临界骨缺损存在成骨效率低、安全性差等问题。而以非病毒纳米粒子为基因载体构建的基因强化型骨组织工程移植物,具有更高的成骨效率和安全性,引起了国内外学者的广泛关注和研究。目的:对当前国内外有关纳... 详细信息

背景:传统的骨组织工程技术治疗临界骨缺损存在成骨效率低、安全性差等问题。而以非病毒纳米粒子为基因载体构建的基因强化型骨组织工程移植物,具有更高的成骨效率和安全性,引起了国内外学者的广泛关注和研究。目的:对当前国内外有关纳米粒子在组织工程成骨基因治疗研究中取得的新技术、新方法以及面临的挑战等进行综述,旨在为纳米粒子介导的骨组织工程基因治疗研究提供参考。方法:第一作者在Pub Med、Web of Science和中国知网数据库上进行文献检索,并以“Bone defect repair,Bone tissue engineering,Gene delivery,Nanoparticles,Non-viral gene vector,Sustained release technology,Sequential release,Targeted delivery”作为英文检索词,以“骨缺损修复,骨组织工程,基因递送,纳米粒子,非病毒基因载体,缓释技术,序贯释放,靶向递送”作为中文检索词,最终纳入84篇文献进行总结。结果与结论:(1)在骨缺损愈合的各个生理阶段进行针对性的基因递送可以显著增强骨修复效果。在早期炎症阶段,通过纳米粒子递送抗炎基因来调节炎症反应,可以为后续骨愈合奠定基础;在血管新生期,向局部递送促血管化基因有助于形成高度组织化、可灌注的血管系统,加快骨愈合速度;随着血管化的进行,骨骼的神经再支配也开始发生,此时递送促神经再生的功能性基因有利于促进神经化骨再生;在成骨阶段,通过构建纳米粒子-成骨基因复合物,可以直接提升支架及体内新骨形成的效率。(2)各种有机、无机纳米颗粒、金属有机框架和外泌体等非病毒纳米载体,在骨组织工程基因治疗中具有巨大的潜力,这些纳米基因载体各有其独特的优势和不足,因此在实际应用时,需要根据基因转染效率、生物安全性和成骨特性等因素选择最合适的类型。(3)为了全面提升递送基因的效果,目前主要通过对纳米载体进行各种功能设计来增强基因转染效率,包括增强缓释性和多基因递送序贯性等时间调控能力、增强对骨组织和成骨相关细胞的空间靶向能力、增强跨膜运输效率和细胞核靶向能力等全过程调控手段。(4)未来要进一步推动纳米粒子介导的骨组织工程基因治疗在临床上的应用,还需要克服诸多技术挑战,包括提高有机纳米基因载体的基因转染效率、降低无机纳米载体的生物安全性风险、优化新型纳米载体的生产工艺以及促进其它生理过程与成骨交互作用等,这些问题也是未来骨组织工程基因治疗的研究热点和潮流。

关键词：骨缺损修复骨组织工程基因递送纳米粒子非病毒基因载体缓释技术序贯释放靶向性递送

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STUDY ON PHASE-SEPARATION OF PMMA/SAN BLENDS INDUCED BY GLASS BEADS THROUGH DYNAMIC RHEOLOGICAL MEASUREMENTS

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Chinese Journal of Polymer Science 2006年第1期24卷 53-60页

作者： Miao Du jian-hua Gong Min zuo Qiang Zheng Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Fluid Power Control and Transmission Zhejiang University Hangzhou 310027 China

Based on the premise that the addition of glass beads （GB） could hardly influence the linear viscoelasticity in low frequency （ω） region for homogeneous polymer systems, the dynamic rheological behaviors of unfilled and filled poly（methyl methyacrylate）（PMMA）/poly（styrene-co-acrylonitrile）（SAN） blends were studied in order to explore the effect of GB on the phase-separation of binary polymer matrix. Results show that GB has an induced effect on the phase-separation, which embodies that the phase-separation temperature （Ts） of PMMA/SAN blend filled with GB is lower than that of the unfilled system. The higher content of GB, the higher is the ＂secondary plateau＂ of ω in the terminal region of storage modulus （G＇） versus ω plot. The ＂secondary plateau＂ appearing in the terminal region is attributed to the phase-separation of PMMA/SAN blends and it becomes more fiat for filled polymer blends under the same conditions. However, it is suggested that this kind of ＂induced effect＂ is related to the GB content; the higher content of GB particles might enhance the interaction between the particles and polymer matrix. Moreover, it is found that the addition of GB also has an influence more or less on the morphology and domain size of polymer matrix. It is believed that the plot of dynamic viscosity （η＇） versus the loss viscosity （η＂） is sensitive to examine the effect induced by GB on the phase-separation of binary polymer matrix.

关键词： PMMA/SAN blends Glass beads Phase-separation Rheological behavior. poly(styrene-co-acrylonitrile)

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Electron delocalization-enhanced sulfur reduction kinetics on an MXene-derived heterostructured electrocatalyst

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Nano Research 2024年第8期17卷 7153-7162页

作者： Yunmeng li Yinze zuo Xiang li Yongzheng Zhang Cheng Ma Xiaomin Cheng jian Wang Jitong Wang Hongzhen lin licheng ling State Key Laboratory of Chemical Engineering Key Laboratory of Specially Functional Polymeric Materials and Related Technology(Ministry of Education)East China University of Science and TechnologyShanghai 200237China Institute of New Energy Materials and Engineering College of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Specially Functional Polymeric Materials and Related Technology(Ministry of Education) School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China i-Lab&CAS Key Laboratory of Nanophotonic Materials and Device Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123China Helmholtz Institute Ulm(HIU) D89081 UlmGermany

lithium-sulfur(li-S)batteries mainly rely on the reversible electrochemical reaction of between lithium ions(li^(+))and sulfur species to achieve energy storage and conversion,therefore,increasing the number of free li^(+)and improving the li^(+)diffusion kinetics will effectively enhance the cell ***,Mo-based MXene heterostructure(MoS_(2)@Mo_(2)C)was developed by partial vulcanization of Mo_(2)C MXene,in which the introduction of similar valence S into Mo-based MXene(Mo_(2)C)can create an electron delocalization *** theoretical simulations and electrochemical characterisation,it is demonstrated that the MoS_(2)@Mo_(2)C heterojunction can effectively promote ion desolvation,increase the amount of free li^(+),and accelerate li^(+)transport for more efficient polysulfide *** addition,the MoS_(2)@Mo_(2)C material is also capable of accelerating the oxidation and reduction of polysulfides through its sufficient defects and vacancies to further enhance the catalytic ***,the li-S battery with the designed MoS_(2)@Mo_(2)C electrocatalyst performed for 500 cycles at 1 C and still maintained the ideal capacity(664.7 mAh·g^(−1)),and excellent rate performance(567.6 mAh·g^(−1)at 5 C).Under the extreme conditions of high loading,the cell maintained an excellent capacity of 775.6 mAh·g^(−1)after 100 *** also retained 838.4 mAh·g^(−1)for 70 cycles at a low temperature of 0℃,and demonstrated a low decay rate(0.063%).These results indicate that the delocalized electrons effectively accelerate the catalytic conversion of lithium polysulfide,which is more practical for enhancing the behaviour of li-S batteries.

关键词： delocalized electron lithium sulfur batteries MXene-based heterostructures catalytic desolvation multi-catalytic sites

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Prediction calculations for the first criticality of the HTR-PM using the PANGU code

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Nuclear Science and Techniques 2021年第9期32卷 9-15页

作者： Ding She Bing Xia Jiong Guo Chun-lin Wei jian Zhang Fu li Lei Shi zuo-Yi Zhang Institute of Nuclear and New Energy Technology(INET) Tsinghua UniversityBeijing 100084China

The high-temperature reactor pebble-bed mod-ule(HTR-PM)is a modular high-temperature gas-cooled reactor demonstration power *** first criticality experiment is scheduled for the latter half of *** performing the first criticality experiment,a prediction calculation was performed using PANGU *** paper presents the calculation details for predicting the HTR-PM first criticality using PANGU,including the input model and parameters,numerical results,and uncertainty *** accuracy of the PANGU code was demonstrated by comparing it with the high-fidelity Monte Carlo solution,using the same input *** should be noted that k eff can be significantly affected by uncertainties in nuclear data and certain input parameters,making the criticality calculation ***,the PANGU is used to pre-dict the critical loading height of the HTR-PM first criti-cality under design conditions,which will be evaluated in the upcoming experiment later this year.

关键词： HTR-PM First criticality Prediction PANGU

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Form factors for B meson weak decays in QCD light cone sum rules with a chiral current correlator

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Chinese Science Bulletin 2014年第29期59卷 3771-3786页

作者： zuo-Hong li Department of Physics Yantai University

We report some applications of QCD light cone sum rules(LCSR)to B meson weak *** emphasis is on estimates of the form factors for B decays into a pseudoscalar(P)/vector(V)meson,with a certain chiral current *** main new ingredient,as compared with the case of the standard correlators,is that in the operator product expansion calculations,the contributions due to the twist-3 distribution amplitudes of the related light mesons,which are less known and would bring a larger uncertainty to the calculations with the standard correlators,cancel out fully in the B!P case and do out partially in the B!V *** important observation,which is similar to that in soft collinear effective theory,is made in twist-3 approximation:whereas only one independent form factor is needed for parameterizing the hadronic matrix elements for a B!P transition induced by all the relevant heavy-light quark currents,there exist two independent form factors under the condition of neglecting the terms suppressed by a factor of m2V,for the B!V ***,the improved LCSR approach could be of stronger predictive power for the weak form ***,this approach is employed to understand the B!D transitions by introducing a leading twist-2 DA for an energetic D meson,combined with some of other QCDbased approaches.A detailed QCD next-to-leading order calculation of the B!p form factors is presented for an illustrative purpose,and the sum rule results are used to extract the Cabibbo–Kobayashi–Maskawa matrix element jVubj from the latest BaBar data.

关键词： B介子衰变求和规则 QCD 外形电流手性光锥矩阵元素

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Percutaneous cryosurgery for the treatment of hepatic colorectal metastases

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World Journal of Gastroenterology 2008年第9期14卷 1430-1436页

作者： Ke-Cheng Xu li-Zhi Niu Wei-Bing He Yi-Zi Hu jian-Sheng zuo Cryosurgery Center for Cancer Fuda Cancer Hospital Guangzhou Guangzhou 510300 Guangdong Province China

AIM:To determine the safety and efficacy of efficacy of percutaneous cryosurgery for treatment of patients with hepatic colorectal metastases. METHODS: Three hundred and twenty-six patients with non-resectable hepatic colorectal metastases underwent percutaneous cryosurgery under the guidance of ultrasound or CT. Follow-up was 1 mo after cryosurgery and then every 4 mo thereafter by assessment of tumor markers, liver ultrasonography, and abdominal CT. For lesions suspicious of recurrence, a liver biopsy was performed and subsequent repeat cryosurgery was given if histology was positive for cancer. RESULTS: All patients underwent a total of 526 procedures of cryosurgery. There were 151 patients who underwent repeat procedures of cryosurgery for recurrent tumors in the liver and extrahepatic places. At 3 mo after cryosurgery, carcinoembryonic antigen (CEA) levels in 197 (77.5%) patients who had elevated markers before cryosurgery decreased to normal range. Among 280 patients who received CT following-up, cryotreated lesions showed complete response (CR) in 41 patients (14.6%), partial response (PR) in 115 patients (41.1%), stable disease (SD) in 68 patients (24.3%) and progressive disease (PD) in 56 patients (20%). The recurrence rate was 47.2% during a median follow-up of 32 mo (range, 7-61). Sixty one percent of the recurrences were seen in liver only and 13.9% in liver and extrahepatic areas. The recurrence rate at cryotreated site was only 6.4% for all cases. During a median follow-up of 36 mo (7-62 mo), the median survival of all patient was 29 mo (range 3-62 mo). Overall survival was 78%, 62%, 41%, 34% and 23% at 1, 2, 3, 4 and 5 years, respectively, after the treatment. Patients with tumor size less than 3 cm, tumor in right lobe of liver, lower CEA levels (< 100 ng/dL) and post- cryosurgery TACE had higher survival rate. There wasno significant difference in terms of survival based on the number of tumors, pre-cryosurgery chemotherapy and the timing of the dev

关键词： Hepatic colorectal metastases Hepatic cryosurgery Percutaneous cryosurgery Colorectal cancer

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Identification of a novel testis-specific gene and its potential roles in testis development/spermatogenesis

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Asian Journal of Andrology 2005年第2期7卷 127-137页

作者： Lan-LanYin jian-Minli zuo-MinZhou Jia-HaoSha KeyLaboraryofReproductiveMedicine NanjingMedicalUniversityHangzhongRoadNanjing210029China

Aim:To identify and characterize a novel gene with potential roles in testis development and spermatogenesis. Methods:A cDNA microarray was constructed from a human testis large insert cDNA library and hybridized with probes of human or mouse adult and fetal *** expressed genes were isolated and ***-PCR was used to test the tissue distribution of the genes of interest and in situ hybridization was performed to localize the gene expression in the mouse testis.A range of bioinformatical programs including Gene Runner,SMART,NCBI Blast and Emboss CpGPlot were used to characterize the new gene's ***:A novel testis-specific gene, NYD-SP5,was differentially expressed in fetal and adult *** deduced protein structure of NYD-SP5 was found to contain an IQ motif (a short calmodulin-binding motif containing conserved lie and Gin residues),a Carbam- ate kinase-like domain,a Zn-dependent exopeptidase domain and a lactate dehydrogenase (LDH) C-terminal-like ***-PCR analysis revealed that NYD-SP5 was predominantly expressed in the testis but not in other 15 tissues *** situ hybridization and RT-PCR examinations revealed that the expression of NYD-SP5 was confined in the male germ cell but not present in the somatic cell in the ***:NYD-SP5 is a newly found testis- specific gene with potential roles in testis development and spermatogenesis through a calmodulin-activated enzyme.

关键词： spermatogenesis testis calmodulin

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