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| 1 | Effect of Helicobacter pylori infection on gastric epithelial proliferation in progression from normal mucosa to gastric carcinoma显示文摘EfectofHelicobacterpyloriinfectionongastricepithelialproliferationinprogressionfromnormalmucosatogastriccarcinomaLIUWenZhon... | LIU Wen Zhong, ZHENG Xiong, SHI Yao, DONG Quan Jiang and XIAO Shu Dong | 1998 | World Journal of Gastroenterology1998,4,3: | 30 |
| 2 | A 12-year cohort study on the efficacy of plasmaderived hepatitis B vaccine in rural newborns显示文摘AIM To understand the anti-HBs persistenceand the long-term preventive efficacy in ruralnewborns after vaccination with plasma-derivedhepatitis B vaccine.METHODS In the time of expanded program onimmunization(EPI),the newborns werevaccinated with 10μg×3 doses of hepatitis Bvaccine and 762 newborns who were HBsAgnegative after primary immunization wereselected for cohort observation from 1986 to1998.Their serum samples were detectedqualitatively and quantitatively for hepatitis Binfecting markers,including HBsAg,anti-HBsand anti-HBc by SPRIA Kits.The annual HBsAgpositive conversion rate was counted by life-table method.RESULTS①The anti-HBs positive rate was94.44% for the babies born to HBsAg negativemothers and 84.21% for those born to HBsAgpositive mothers in the 1st year afterimmunization,and dropped to 51.31% and52.50% in the 12th year respectively.GMT valuewas dropped from 31.62 to 3.13 and 23.99 to 3.65in the 2nd to the 12th year respectively.Therewas a marked drop in GMT at the 3rd to the 5thyear,and in anti-HBs positive rate at the 9th tothe 10th year.②In the period of 12 yearsobservation,the person-year HBsAg positive conversion rates were 0.12%(5/4150.0)innewborns born to HBsAg negative mothers and0.20%(1/508.0)in those born to HBsAgpositive mothers,and none of the HBsAgpositive converted children became HBsAgchronic carriers.Compared with the baselinebefore immunization,the protective rates were97.19% and 95.32% respectively.CONCLUSION The protective efficacy ofplasma-derived hepatitis B vaccine persisted atleast 12 years,and a booster dose seems notnecessary within at least 12 years after theprimary three-doses immunization to newbornsborn to HBsAg negative mothers. | Hong Bin Liu Zong Da Meng Jing Chen Ma Chang Quan Han Ying Lin Zhang Zhan Chun Xing Yu Wei Zhang Yu Zhong Liu Hui Lin Cao | 2000 | World Journal of Gastroenterology2000,6,3: | 11 |
| 3 | Development of the Transitional Care Model for nursing care in China's Mainland:A literature review显示文摘Background:The Transitional Care Model(TCM)for nursing care has yet to be implemented in China despite its success in Western countries.However,rapid social changes have demanded an upgrade in the quality of nursing care;in 2010,the Chinese government has acknowledged the need to implement the TCM in China.Objective:This study has the following objectives:(1)perform a thorough review of the literature regarding the development and implementation of the TCM in China's Mainland within the past 5 years;(2)provide a comprehensive discussion of the current status,problems,and strategies related to the implementation of the TCM in China's Mainland;and(3)suggest strategies pertaining to the future of the TCM in China.Design:The current pertinent literature is systematically reviewed.Data sources:Systematic and manual searches in computerized databases for relevant studies regarding the TCM led to the inclusion of 26 papers in this review.Review methods:Abstracts that satisfied the inclusion criteria were reviewed independently by the two authors of this manuscript,and discrepancies were resolved through discussion.The same reviewers independently assessed the paper in its entirety for selected abstracts.Results:The present English literature reviewrevealed a paucity of updated information about the development and implementation of the TCM in China's Mainland.Nevertheless,the dramatic growth of the TCM in the past 5 years has had a vital impact within the society and in nursing development.This review also revealed numerous issues regarding the focus of the TCM.Overall implications for practiceandrecommendations for future researchare discussed.Conclusion:Despite the potential of this nursing model to have a successful and beneficial impact in China's Mainland,it remains an under-researched topic.Further research on education and training as well as premium policies for nurses under the TCM are needed. | Zeng-Jie Ye Mei-Ling Liu Rui-Qing Cai Mei-Xia Zhong Hui Huang Mu-Zhi Liang Xiao-Ming Quan | 2016 | International Journal of Nursing Sciences2016,3,1: | 10 |
| 4 | Biomaterial-based strategies for maxillofacial tumour therapy and bone defect regeneration显示文摘Issues caused by maxillofacial tumours involve not only dealing with tumours but also repairing jaw bone defects.In traditional tumour therapy,the systemic toxicity of chemotherapeutic drugs,invasive surgical resection,intractable tumour recurrence,and metastasis are major threats to the patients’lives in the clinic.Fortunately,biomaterial-based intervention can improve the efficiency of tumour treatment and decrease the possibility of recurrence and metastasis,suggesting new promising antitumour therapies.In addition,maxillofacial bone tissue defects caused by tumours and their treatment can negatively affect the physiological and psychological health of patients,and investment in treatment can result in a multitude of burdens to society.Biomaterials are promising options because they have good biocompatibility and bioactive properties for stimulation of bone regeneration.More interestingly,an integrated material regimen that combines tumour therapy with bone repair is a promising treatment option.Herein,we summarized traditional and biomaterial-mediated maxillofacial tumour treatments and analysed biomaterials for bone defect repair.Furthermore,we proposed a promising and superior design of dual-functional biomaterials for simultaneous tumour therapy and bone regeneration to provide a new strategy for managing maxillofacial tumours and improve the quality of life of patients in the future. | Bowen Tan Quan Tang Yongjin Zhong Yali Wei Linfeng He Yanting Wu Jiabao Wu Jinfeng Liao | 2021 | International Journal of Oral Science2021,13,1: | 9 |
| 5 | Corneal flap morphological analysis using anterior segment optical coherence tomography in laser in situ keratomileusis with femtosecond lasers versus mechanical microkeratome显示文摘AIM:To assess and compare the flap morphology using anterior segment optical coherence tomography (AS-OCT) in laser in situ keratomileusis(LASIK) with Femto LDV femtosecond lasers versus Hansatome mechanical Microkeratome.· METHODS:AS-OCT (Visante) was used to compare 1 month postoperatively the morphology of the flaps created with Femto LDV femtosecond lasers or Hansatome Microkeratome.The intendedfiap thickness was 110μm and 160μm respectively.The thickness of twenty-five points across each flap,which were 0mm,1.5mm,2.5mm,and 3.5mm to the corneal vertex on the horizontal,vertical,45° and 135° meridian respectively,was evaluated.· RESULTS:One month postoperative,the central flap thickness in the Femto LDV group was 107.43±4.70μm,while 125.90±17.50μm in the Hansatome group.The difference between the actual and the expectedfiap thickness was 5.61±3.84μm and 31.52±12.27μm,respectively.The Hansatome group had presented a statistically significant result (P <0.001).Flap morphology showed a more regular planar shape in the Femto LDV group and a meniscus shape in the Hansatome group.· CONCLUSION:AS-OCT is a direct and fast procedure to assess the flap morphology.The morphology by AS-OCT showed that the flaps created with Femto LDV femtosecond laser were more accurate and regular than the flaps created with Hansatome microkeratome. | Xiao-Xiao Zhang Xing-Wu Zhong Jun-Shu Wu Zheng Wang Ke-Ming Yu Quan Liu and Bin Yang | 2012 | International Journal of Ophthalmology(English edition)2012,5,1: | 9 |
| 6 | SCUTEBARSATINE A, A NEW NEOCLERODANE-TYPE DITERPENOID ALKALOID FROM SCUTELLARIA BARBATA显示文摘SCUTEBARSATINEA,ANEWNEOCLERODANE-TYPEDITERPENOIDALKALOIDFROMSCUTELLARIABARBATA¥ZhaoQuanWANG;FengMingXU;XianZhongYANandYuanZHU... | Zhao Quan WANG Feng Ming XU Xian Zhong YAN and Yuan ZHU(Anhui Institute of Medical Sciences, Hefei, 230061)(Instrumental Analysis Center, Academy of Military Sciences, Beijing, 100850) | 1996 | Chinese Chemical Letters1996,7,4: | 9 |
| 7 | Rapid detection of sepsis complicating acute necrotizing pancreatitis using polymerase chain reaction显示文摘INTRODUCTIONAcute narcotizing pancreatitis usually takes a severe clinical course and is associated with multiple organ dysfunction .With the further understanding of pathophysiological events of acute pancreatisis and the therapeutic measuses taken by the clinicians ,the patients can pass through the critical carry stages ,and then the septic complication caused by rtanslocated bacteria, mostly gram-negative microbes from the intestines ensues[1]. | Wei Zhong Zhang1 Tian Quan Han2 Yao Qing Tang2 Sheng Dao Zhang2 1Department of Surgery. Huangyan First Hospital, Huangyan 318020, Zhejiang Province. China 2Department of Surgery. Ruijin Hospital. Shanghai Second Medical University. Shanghai 200025. ChinaDr. Wei Zhong Zhang, graduated from Shanghai Second MedicalUniversity receiving master degree of surgery in 1999 he is devoted to basic and clinical investigation on severe acute pancreatitis and has one paper published. | 2001 | World Journal of Gastroenterology2001,7,2: | 7 |
| 8 | Red/orange dual-emissive carbon dots for pH sensing and cell imaging显示文摘The dual-emissive N,S co-doped carbon dots (N,S-CDs) with a long emission wavelength were synthesized via solvothermal method.The N,S-CDs possess relatively high photoluminescence (PL) quantum yield (QY) (35.7%) towards near-infrared fluorescent peak up to 648 nm.With the advanced characterization techniques including X-ray photoelectron spectroscopy (XPS),Fourier transform infrared spectroscopy (FTIR),etc.It is found that the doped N,S elements play an important role in the formation of high QY CDs.The N,S-CDs exist distinct pH-sensitive feature with reversible fluorescence in a good linear relationship with pH values in the range of 1.0-13.0.What is more,N,S-CDs can be used as an ultrasensitive Ag+ probe sensor with the resolution up to 0.4 μM.This finding will expand the application of as prepared N,S-CDs in sensing and environmental fields. | Miaoran Zhang Rigu Su Jian Zhong Ling Fei Wei Cai Qingwen Guan Weijun Li Neng Li Yusheng Chen Lulu Cai Quan Xu | 2019 | Nano Research2019,12,4: | 6 |
| 9 | Additional laparoscopic gastrectomy after noncurative endoscopic submucosal dissection for early gastric cancer: A single-center experience显示文摘BACKGROUND The necessity of additional gastrectomy for early gastric cancer (EGC) patients who do not meet curative criteria after endoscopic submucosal dissection (ESD) is controversial. AIM To examine the clinicopathologic characteristics of patients who underwent additional laparoscopic gastrectomy after ESD and to determine the appropriate strategy for treating those after noncurative ESD. METHODS We retrospectively studied 45 patients with EGC who underwent additional laparoscopic gastrectomy after noncurative ESD from January 2013 to January 2019 at the Cancer Hospital of the Chinese Academy of Medical Sciences. We analyzed the patients’ clinicopathological data and identified the predictors of residual cancer (RC) and lymph node metastasis (LNM). RESULTS Surgical specimens showed RC in ten (22.2%) patients and LNM in five (11.1%).Multivariate analysis revealed that positive horizontal margin [odds ratio (OR)=13.393, 95% confidence interval (CI): 1.435-125, P=0.023] and neural invasion (OR=14.714, 95%CI: 1.087-199, P=0.043) were independent risk factors for RC. Undifferentiated type was an independent risk factor for LNM (OR=12.000, 95%CI: 1.197-120, P=0.035). Tumors in all patients with LNM showed submucosal invasion more than 500 μm. Postoperative complications after additional laparoscopic gastrectomy occurred in five (11.1%) patients, and no deaths occurred among patients with complications. CONCLUSION Gastrectomy is necessary not only for patients who have a positive margin after ESD, but also for cases with neural invasion, undifferentiated type, and submucosal invasion more than 500 μm. Laparoscopic gastrectomy is a safe, minimally invasive, and feasible procedure for additional surgery after noncurative ESD. However, further studies are needed to apply these results to clinical practice. | Yan-Tao Tian Fu-Hai Ma Gui-Qi Wang Yue-Ming Zhang Li-Zhou Dou Yi-Bin Xie Yu-Xin Zhong Ying-Tai Chen Quan Xu Dong-Bing Zhao | 2019 | World Journal of Gastroenterology2019,25,29: | 6 |
| 10 | Alterations of brain local functional connectivity in amnestic mild cognitive impairment显示文摘Background:Resting-state functional magnetic resonance imaging studies using a regional homogeneity(ReHo)method have reported that amnestic mild cognitive impairment(aMCI)was associated with abnormalities in local functional connectivity.However,their results were not conclusive.Methods:Seed-based d Mapping was used to conduct a coordinate-based meta-analysis to identify consistent ReHo alterations in aMCI.Results:We identified 10 studies with 11 datasets suitable for inclusion,including 378 patients with aMCI and 435 healthy controls.This meta-analysis identified significant ReHo alterations in patients with aMCI relative to healthy controls,mainly within the default mode network(DMN)(bilateral posterior cingulate cortex[PCC],right angular gyrus,bilateral middle temporal gyri,and left parahippocampal gyrus/hippocampus),executive control network(right superior parietal lobule and dorsolateral prefrontal cortex),visual network(right lingual gyrus and left middle occipital gyrus),and sensorimotor network(right paracentral lobule/supplementary motor area,right postcentral gyrus and left posterior insula).Significant heterogeneity of ReHo alterations in the bilateral PCC,left parahippocampal gyrus/hippocampus,and right superior parietal lobule/angular gyrus was observed.Exploratory meta-regression analyses indicated that general cognitive function,gender distribution,age,and education level partially contributed to this heterogeneity.Conclusions:This study provides provisional evidence that aMCI is associated with abnormal ReHo within the DMN,executive control network,visual network,and sensorimotor network.These local functional connectivity alterations suggest coexistence of functional deficits and compensation in these networks.These findings contribute to the modeling of brain functional connectomes and to a better understanding of the neural substrates of aMCI.Confounding factors merit much attention and warrant future investigations. | Dan Zheng Wei Xia Zhong Quan Yi Pan Wen Zhao Jian Guo Zhong Hai Cun Shi Hua Liang Li Zhen Yu Dai Ping Lei Pan | 2018 | Translational Neurodegeneration2018,7,1: | 5 |
| 11 | Stromatolite characteristics of Mesoproterozoic Shennongjia Group in the northern margin of Yangtze Block, China显示文摘Mesoproterozoic Shennongjia Group in Shennongjia Area can be divided into three subgroups in ascender order. Of which the lower subgroup includes Yingwodong, Dayanping, Macaoyuan, Luanshigou, Dawokeng and Kuangshishan formations;the middle subgroup is formed by Yemahe, Wenshuihe and Shicaohe formations;the upper subgroup consists of Songziyuan and Wagangxi formations. Stromatolites developed very well in the carbonate rocks of each subgroup in Shennongjia Group. Based on descriptions of stromatolites macrotypes and their characteristics, this paper studied the formation environments, discussed the relationship among types, sizes, abundance of stromatolites and sedimentary environment, and established the formation and development pattern of stromatolites. As a result, this research also reveals the paleoenvironment and paleoclimate during the period of the Shennongjia Group deposited, which is beneficial to the study of paleoenvironment, paleogeography and paleoclimate, stratigraphic succession and regional correlation of the northern edge of Yangtze block. Stromatolites of Shennongjia Group are mainly conical, columnar, domal, wavy, stratiform and stromatolite reefs. The columnar and conical stromatolites are well developed. Conical stromatolites are mainly monomers, with a variety of pyramidal types, ranging in diameter from a few millimeters to several meters and formed in the high energy subtidal zone and tidal lagoon environment. Most of the columnar stromatolites are medium to small sizes implied a wide and gentle slope environment at that time. Stratiform (including wavy) stromatolites are larger scales and extends far away and distributed most widely in almost every horizon in the carbonate rocks. Stratiform stromatolites can be formed in low energy environments such as subtidal and intertidal zones and supratidal belts. Wavy stromatolites often developed in the hydrodynamic energy condition from weak energy intertidal zone gradually strengthened to the below of the high energy supratidal. Although stromatolite reefs can be a single or multiform combination, they developed mainly consisted of laminar or small walled columnar and large domal stromatolites. Shicaohe Formation also partially developed large domical stromatolites, the depositional environment is from the upper intertidal to supratidal zone. Stromatolite in Shennongjia Group usually appears as a combination of “Stratiform (wavy)-dome-columnar-coniform ” or “stratiform-dome-coniform-columnar-dome-stratiform ” vertieally, which represents the seawater depth from shallower to deeper or from shallow to deep and then to shallow again. These phenomenons generally reflected a stable sea level and companied with a high frequency oscillation. Comprehensive researches on the stratigraphy, sedimentary facies, sedimentary environment and the stromatolite types and their characteristics in the Shennongjia Group indicated that the Shennongjia Area is located on a gentle slope of carbonate platform in the passive continental edge, generally, i.e., one of warm and humid climate shallow water zone or/and a cold-drought climate, and had been experienced with eustatic cycles during the Shennongjia Group deposited. | Hong-wei Kuang Zheng-xiu Fan Yong-qing Liu Nan Peng Zhi-cai Zhu Zhen-rui Yang Zhi-xian Wang Hui-liang Yu Quan Zhong | 2019 | China Geology2019,2,3: | 5 |
| 12 | Computer Controlled Polishing of the Off-axis Aspheric Mirrors显示文摘In this paper, the manufacturing and testing procedures to make large off-axis aspherical mirrors are presented. The difficulties in polishing and testing for both circular aperture and rectangular aperture mirrors are previewed, and a possible solution is given. The two mirrors have been polished by means of CCOS, and the final accuracy is 25nm rms for 770mm×210mm rectangular mirror and 20nm rms for φ600mm circular mirror. These results just meet the optical tolerances specified by the designer, and the manufacturing and testing procedures presented here show good ability to make the large off-axis aspherical mirrors. | ZHANG Xue jun,WENG Zhi cheng,ZHANG Zhong yu, WANG Quan dou,ZHANG Feng (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130022, China) | 2001 | 光学精密工程2001,9,5: | 4 |
| 13 | Extraordinary simultaneous enhancement of the coercivity and remanence of dual alloy HRE-free Nd-Fe-B sintered magnets by post-sinter annealing显示文摘Post-sinter annealing process plays an important role in the microstructures and magnetic properties of the Nd-Fe-B sintered magnets.In this paper,systematically investigated are the magnetic properties and microstructures of the as-sintered and post-sinter annealed Nd-Fe-B magnets with Pr-Fe-Ga boundary addition.Two choice consecutive annealing methods are adopted at high and low temperatures,namely the 1 st annealing at 880℃ for 2 h and then the 2^(nd) annealing at 440℃ for 3 h.It is exceptional to find out that both the remanence and coercivity are improved after 2^(nd) annealing process for this type of magnet.The coercivity is hugely increased from 10.09 kOe for the as-sintered sample to 17.19 kOe for the 2^(nd) annealed magnet,with a significant increment of 70.37%in coercivity.The extraordinary magnetic properties of B_(r)=14.44 kGs,H_(cj)=17.19 kOe and(BH)_(max)=51.08 MGOe are obtained for the designated Nd-Fe-B sintered magnets without heavy rare earth(HRE)elements manufactured by dual alloy method.The Curie temperature is monotonically decreased from 634 K to 602 K while the c-axis alignment degree is optimized after annealing.Microstructural observation and analysis indicate that the elemental distribution patterns are altered after the 2^(nd) annealing.The diffusion of the aggregate(Pr,Nd,Cu,Ga)-rich phase from triple junctions into the grain boundary regions is ascribed to the formation of thin and continuous grain boundary layer,which is critical to improve the microstructures and magnetic properties. | Qingfang Huang Qingzheng Jiang Jifan Hu Sajjad Ur Rehman Gang Fu Qichen Quan Jixiang Huang Deqin Xu Dakun Chen Zhenchen Zhong | 2022 | Journal of Materials Science & Technology2022,,11: | 3 |
| 14 | Synthesis and antitumor activity of novel 10-amino acids ester homocamptothecin analogues显示文摘九外消旋的 homocamptothecin 衍生物被综合,在 vitro antitumor,活动被标准 MTT 方法评估。结果比 iritecan 显示出复合有的更高的 antitumor 活动的那一些。 | Liang You Wan Nian Zhang Zhen Yuan Miao Wei Guo Xiao Ying Che Wen Ya Wang Chun Quan Sheng Jiang Zhong Yao Ting Zhou | 2008 | Chinese Chemical Letters2008,19,7: | 3 |
| 15 | Total Synthesis of (±)-Calanolide A and Its Anti-HIV Activity显示文摘Anti-HIV agent (±)-calanolide A has been synthesized by a four-step approach startingfrom phloroglucinol, including the Pechmann reaction, Friedel-Crafts acylation, cyclization,chromenylation and Luche reduction. | Chun Mei ZHOU Lin WANG Ming Long ZHANG Zhi Zhong ZHAO (Institute of Materia Medica, Peking Union Medical College &Chinese Academy of Medical Sciences, Beijing 100050)Xing Quan ZHANG Xiang Hong CHEN Hong Shan CHEN (Institute of Medicinal Biotechno | 1998 | Chinese Chemical Letters1998,9,5: | 3 |
| 16 | Survival outcomes and prognostic indicators for gastric cancer patients with positive peritoneal wash cytology but no peritoneal metastasis after radical gastrectomy显示文摘BACKGROUND Positive peritoneal wash cytology with no peritoneal metastasis(CY1P0)is a special type of distant gastric cancer metastasis,which describes a patient with positive peritoneal lavage cytology,but no definitive peritoneal metastasis,and there are no widely accepted treatment guidelines.We enrolled 48 primary CY1P0 gastric cancer patients treated by radical gastrectomy in this study.Our study illustrated the efficacy of radical gastrectomy for CY1P0 gastric cancer patients,and suggested that the pathological N factor and vascular invasion were significant independent risk factors for overall survival(OS).AIM To assess the survival of CY1P0 gastric cancer patient post-radical gastrectomy,and to identify factors associated with long-term prognosis.METHODS Our study included 48 patients with primary CY1P0 gastric cancer who had radical gastrectomies at the Cancer Hospital,Chinese Academy of Medical Sciences,Beijing,China between 2013 and 2018.R0 resection was achieved in all 48 patients.Twelve patients received neoadjuvant chemotherapy.Thirty patients received adjuvant chemotherapy and four received adjuvant chemoradiotherapy.OS statistics were available for 48 patients.Follow-up continued through March 2020.Univariate and multivariate analyses were performed using a Cox proportional hazards model to identify prognostic factors.RESULTS Median OS was 22.0 mo(95%confidence interval:13.366-30.634 mo)post-surgery.Univariate analyses demonstrated that tumor site(P=0.021),pathological N factor(P=0.001),pathological T factor(P=0.028),vascular invasion(P=0.046),and the level of CA199 prior to initiating therapy(P=0.002)were significant risk factors for OS.Multivariate analyses demonstrated that pathological N factor(P=0.001)and vascular invasion(P=0.031)were significant independent risk factors for OS.CONCLUSION This study suggested that radical gastrectomy may be efficient for CY1P0 gastric cancer patient post-radical gastrectomy and the pathological N factor and vascular invasion are significant independent risk factors for OS. | Wen-Zhe Kang Yu-Xin Zhong Fu-Hai Ma Li-Yan Xue Jian-Ping Xiong Shuai Ma Yang Li Yi-Bin Xie Xu Quan Yan-Tao Tian | 2021 | World Journal of Gastrointestinal Oncology2021,13,1: | 3 |
| 17 | THE THEORETICAL STUDIES OF PRODUCT ALIGNMENT OF THE REACTIONS OF Na,F WITH CH_3I显示文摘The NaI and IF product rotational alignment of the reactionsof Na,F+CH3I has been theoretically studied in a LEPS PES.Theproduct alignment versus the relative translational energy of the reactantshas been obtained. | Ke Li HAN Guo Zhong HE Nan Quan LOU State Key Laboratory of Molecular Reaction Dynamics,Dalian Institute of Chemical Physics,CAS,Dalian 116012,China | 1993 | Chinese Chemical Letters1993,4,6: | 3 |
| 18 | Effects of Cerium on Microstructures and Mechanical Properties of Zn-22%Al Vibration Damping Alloy显示文摘Using natural aging and artificial aging treatment, the effects of cerium on microstructures and mechanical properties of Zn 22%Al vibration damping alloy were studied by optical microscope, transmission electron microscope and scanning electron microscope. The results show that cerium can refine the microstructure of Zn 22%Al alloy, slow the grain growth and retain the equiaxial degree during aging. The strength of Zn 22%Al (0 07%~0 20%)Ce alloy and Zn 22%Al alloy remains constant after aging below the hot rolling temperature of 80 ℃, and cerium can improve the strength and the stability of mechanical properties of Zn 22%Al alloy. | PANG Shao ping, SHI Yun bao, LI Jun, YANG Bin jiu, QUAN Mei hua, QIAO Yan hui, ZHANG Chi zhong (College of Mechanical Engineering, Beihua University, Jilin 132021, China) | 2000 | Journal of Rare Earths2000,18,4: | 3 |
| 19 | Efficient reinforcement learning in continuous state and action spaces with Dyna and policy approximation显示文摘Dyna is an effective reinforcement learning (RL) approach that combines value function evaluation with model learning.However,existing works on Dyna mostly discuss only its efficiency in RL problems with discrete action spaces.This paper proposes a novel Dyna variant,called Dyna-LSTD-PA,aiming to handle problems with continuous action spaces.Dyna-LSTD-PA stands for Dyna based on least-squares temporal difference (LSTD)and policy approximation.Dyna-LSTD-PA consists of two simultaneous,interacting processes.The learning process determines the probability distribution over action spaces using the Gaussian distribution;estimates the underlying value function,policy,and model by linear representation;and updates their parameter vectors online by LSTD(,t).The planning process updates the parameter vector of the value function again by using ofttine LSTD(2).Dyna-LSTD-PA also uses the Sherman-Morrison formula to improve the efficiency of LSTD(,t),and weights the parameter vector of the value function to bring the two processes together.Theoretically,the global error bound is derived by considering approximation,estimation,and model errors.Experimentally,Dyna-LSTD-PA outperforms two representative methods in terms of convergence rate,success rate,and stability performance on four benchmark RL problems. | Shan ZHONG Quan LIU Zongzhang ZHANG Qiming FU | 2019 | Frontiers of Computer Science2019,13,1: | 3 |
| 20 | Vascularized bone regeneration accelerated by 3D-printed nanosilicate-functionalized polycaprolactone scaffold显示文摘Critical oral-maxillofacial bone defects,damaged by trauma and tumors,not only affect the physiological functions and mental health of patients but are also highly challenging to reconstruct.Personalized biomaterials customized by 3D printing technology have the potential to match oralmaxillofacial bone repair and regeneration requirements.Laponite(LAP)nanosilicates have been added to biomaterials to achieve biofunctional modification owing to their excellent biocompatibility and bioactivity.Herein,porous nanosilicate-functionalized polycaprolactone(PCL/LAP)was fabricated by 3D printing technology,and its bioactivities in bone regeneration were investigated in vitro and in vivo.In vitro experiments demonstrated that PCL/LAP exhibited good cytocompatibility and enhanced the viability of bone marrow mesenchymal stem cells(BMSCs).PCL/LAP functioned to stimulate osteogenic differentiation of BMSCs at the mRNA and protein levels and elevated angiogenic gene expression and cytokine secretion.Moreover,BMSCs cultured on PCL/LAP promoted the angiogenesis potential of endothelial cells by angiogenic cytokine secretion.Then,PCL/LAP scaffolds were implanted into the calvarial defect model.Toxicological safety of PCL/LAP was confirmed,and significant enhancement of vascularized bone formation was observed.Taken together,3D-printed PCL/LAP scaffolds with brilliant osteogenesis to enhance bone regeneration could be envisaged as an outstanding bone substitute for a promising change in oral-maxillofacial bone defect reconstruction. | Xiongcheng Xu Long Xiao Yanmei Xu Jin Zhuo Xue Yang Li Li Nianqi Xiao Jing Tao Quan Zhong Yanfen Li Yuling Chen Zhibin Du Kai Luo | 2021 | Regenerative Biomaterials2021,8,6: | 3 |