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Reducing the global cancer burden with gastrointestinal screening: China's 30 years practice
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作者 Lei Yang Li Feng +5 位作者 Yong Zhu ning wang Xinpu Lu Fanghui Gu Xiaotian Zhang Jiafu Ji 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第3期204-212,共9页
Gastrointestinal(GI) cancers include esophageal [EC(International Classification of Disease 10^(th) revision: C15)], gastric [GC(C16)], and colorectal [CRC(C18-C21)] cancers. China is a high-incidence country of GI ca... Gastrointestinal(GI) cancers include esophageal [EC(International Classification of Disease 10^(th) revision: C15)], gastric [GC(C16)], and colorectal [CRC(C18-C21)] cancers. China is a high-incidence country of GI cancers. 展开更多
关键词 ESOPHAGEAL COLORECTAL GASTROINTESTINAL
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大豆花药优势表达基因GmFLA22a调控雄性育性的功能研究
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作者 曹振林 李金红 +10 位作者 周铭辉 张曼婷 王宁 陈一飞 李嘉欣 祝青松 宫雯珺 杨绪晨 方小龙 和家贤 李美娜 《遗传》 CAS CSCD 北大核心 2024年第4期333-345,共13页
我国大豆对外依赖度高,加速提高大豆产量是目前亟需解决的问题。利用杂种优势是大幅提高作物产量的有效途径之一,近年来基于隐性核不育基因开发的智能雄性不育系统,为快速利用大豆杂种优势提供了可能。但是,大豆雄性不育基因研究相对滞... 我国大豆对外依赖度高,加速提高大豆产量是目前亟需解决的问题。利用杂种优势是大幅提高作物产量的有效途径之一,近年来基于隐性核不育基因开发的智能雄性不育系统,为快速利用大豆杂种优势提供了可能。但是,大豆雄性不育基因研究相对滞后。本研究基于课题组大豆花器官转录组数据,筛选到在大豆早期花药中优势表达基因GmFLA22a,编码含有FAS1结构域的成束状阿拉伯半乳糖蛋白,亚细胞定位表明其可能在内质网中发挥功能。利用基因编辑技术获得Gmfla22a突变体,突变体植株在营养生长阶段与对照组相比没有明显差异,但在生殖生长阶段表现为结实率显著降低。Gmfla22a突变体花粉活力和花粉萌发率均无明显异常,组织切片并染色观察发现,突变体植株花药室壁增厚,花粉粒释放延迟、不完全,这可能是导致Gmfla22a结实率降低的原因。综上,本研究初步揭示GmFLA22a可能参与调控大豆雄性育性,为深入揭示其分子功能提供重要遗传材料,同时为大豆杂种优势利用提供基因资源和理论依据。 展开更多
关键词 大豆 杂种优势 雄性不育 基因编辑 反向遗传学
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Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy
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作者 ning wang Kai Ma +3 位作者 Qiu-da Li Yu-dong Yuan Yan-chun Zhao Li Feng 《China Foundry》 SCIE EI CAS CSCD 2024年第2期147-158,共12页
AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting technology.The microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentat... AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting technology.The microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal testing.The results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the dendrite.Manganese(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these areas.With an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then decreases.Similarly,the area fraction initially decreases and then increases.Additionally,the alloy’s strength and wear resistance decrease,while its plasticity increases.The Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively. 展开更多
关键词 high-entropy alloys MICROSTRUCTURE mechanical properties wear resistance strengthening mechanisms
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All‑Covalent Organic Framework Nanofilms Assembled Lithium‑Ion Capacitor to Solve the Imbalanced Charge Storage Kinetics
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作者 Xiaoyang Xu Jia Zhang +6 位作者 Zihao Zhang Guandan Lu Wei Cao ning wang Yunmeng Xia Qingliang Feng Shanlin Qiao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期246-260,共15页
Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in superca... Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in supercapacitors.The development of these nanofilms offers a promising solution to address the persistent challenge of imbalanced charge storage kinetics between battery-type anode and capacitor-type cathode in lithium-ion capacitors(LICs).Herein,for the first time,custom-made COFBTMB-TP and COFTAPB-BPY nanofilms are synthesized as the anode and cathode,respectively,for an all-COF nanofilm-structured LIC.The COFBTMB-TP nanofilm with strong electronegative–CF3 groups enables tuning the partial electron cloud density for Li^(+) migration to ensure the rapid anode kinetic process.The thickness-regulated cathodic COFTAPB-BPY nanofilm can fit the anodic COF nanofilm in the capacity.Due to the aligned 1D channel,2D aromatic skeleton and accessible active sites of COF nanofilms,the whole COFTAPB-BPY//COFBTMB-TP LIC demonstrates a high energy density of 318 mWh cm^(−3) at a high-power density of 6 W cm^(−3),excellent rate capability,good cycle stability with the capacity retention rate of 77%after 5000-cycle.The COFTAPB-BPY//COFBTMB-TP LIC represents a new benchmark for currently reported film-type LICs and even film-type supercapacitors.After being comprehensively explored via ex situ XPS,7Li solid-state NMR analyses,and DFT calculation,it is found that the COFBTMB-TP nanofilm facilitates the reversible conversion of semi-ionic to ionic C–F bonds during lithium storage.COFBTMB-TP exhibits a strong interaction with Li^(+) due to the C–F,C=O,and C–N bonds,facilitating Li^(+) desolation and absorption from the electrolyte.This work addresses the challenge of imbalanced charge storage kinetics and capacity between the anode and cathode and also pave the way for future miniaturized and wearable LIC devices. 展开更多
关键词 Covalent organic frameworks Lithium-ion capacitor Charge storage kinetic
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Moxibustion at ST36 activates peritoneal macrophages in CTX-induced immunosuppression in mouse model via IFN-γ
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作者 Li Tan Jing Li +5 位作者 Nan Cao Zhi-Yu Ye Bin-Yan Mo Hong-Da Chen Jiang Pan ning wang 《Traditional Medicine Research》 2024年第1期57-68,共12页
Background:To explored whether moxa cone moxibustion can reduce peritoneal inflammation by increasing the content of peritoneal macrophages and B cells via interferon-gamma.Methods:The mice were randomly divided into ... Background:To explored whether moxa cone moxibustion can reduce peritoneal inflammation by increasing the content of peritoneal macrophages and B cells via interferon-gamma.Methods:The mice were randomly divided into three groups with six mice in each group:the control group,model group,and moxibustion group,and the model was established in mice using cyclophosphamide.In the moxibustion group,the mice received moxa cone moxibustion at Zusanli(ST36)for 7 days.Analysis of Peritoneal cell were detected by flow cytometry and immunofluorescence,the protein expression level in the peritoneal fluid were measured with mouse cytokine antibody arrays and verified by enzyme linked immuno sorbent assay test,and RNA-Sequencing was used for peritoneal cell RNA analysis.Results:Our results showed that moxa cone moxibustion could reduce the loss of large peritoneal macrophages and B1 cells(P<0.05).With the cytokine array analysis and enzyme linked immuno sorbent assay test of peritoneal fluid,we found that IFN‐γwas up-regulated in moxibustion group(P<0.05).There were 169 genes were down-regulated in the model group and up-regulated in the moxibustion group while 19 genes that were up-regulated in the model group and down-regulated in the moxibustion group via RNA-sequencing.Kyoto Encyclopedia of Genes and Genomes pathway analysis of 188 intersect differentially expressed genes were found that the top 3 pathways with the highest enrichment of up-regulated genes included Hematopoietic cell lineage,Inflammatory bowel disease and Malaria.The differentially expressed genes visualization protein-protein interaction network shows the top 10 genes including Ifng,Grb2,CCR7,CTLA4,CXCR5,Foxp3,kit,PRF1,CD5 and klrg1.Conclusion:These findings showed that moxa cone moxibustion can alleviate chemotherapy-induced diarrhea by reducing the loss of large peritoneal macrophages and B1 cells in the peritoneal cavity,possibly through up-regulating inflammatory bowel disease signaling pathway via interferon-gamma to regulate the survival and function of large peritoneal macrophages and B1 cells. 展开更多
关键词 MOXIBUSTION IFN-Γ CYCLOPHOSPHAMIDE Zusanli(ST36)
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Natural regulatory T cells and bifunctional regulatory T cells:potential targets of traditional Chinese medicine in treating colitis-associated colon cancer
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作者 ning wang Huan Pei +5 位作者 Li-Wei Xing Si wang Jia-Bao Liao Wei-Bo Wen Yu-Hong Bian Huan-Tian Cui 《Integrative Medicine Discovery》 2024年第6期1-3,共3页
Colon cancer(CRC)is one of the most common malignancies globally,ranking third in terms of new cancer cases and second as a cause of cancer deaths[1].In recent 30 years,the incidence and mortality rates of CRC in Chin... Colon cancer(CRC)is one of the most common malignancies globally,ranking third in terms of new cancer cases and second as a cause of cancer deaths[1].In recent 30 years,the incidence and mortality rates of CRC in China have been increasing,gradually exceeding the global levels[2].Due to the fact that most CRC patients are diagnosed at the advanced stage,the treatment of this disease is challenging and often ineffective.Therefore,prevention and early diagnosis of CRC are crucial. 展开更多
关键词 prevention diagnosis COLON
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Analgesic Effect of Combined Spinal-Epidural Anesthesia and its Effect on TNF-α and CRP Levels in Elderly Patients with Hip Fracture During Surgical Treatment
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作者 Jie Xu Linyan Li ning wang 《Journal of Clinical and Nursing Research》 2024年第3期7-11,共5页
Objective:To observe the analgesic effect of combined spinal and epidural anesthesia on older patients undergoing hip fracture surgery.Method:One hundred and twenty elderly hip fracture surgery patients treated in our... Objective:To observe the analgesic effect of combined spinal and epidural anesthesia on older patients undergoing hip fracture surgery.Method:One hundred and twenty elderly hip fracture surgery patients treated in our hospital from January 2021 to December 2022 were selected and randomly divided into two groups,with 60 cases in the experimental group and 60 in the control group.The experimental group was given combined spinal-epidural anesthesia intervention measures,while the control group was given epidural anesthesia intervention measures.The analgesic effect,tumor necrosis factor-alpha(TNF-α),C-reactive protein(CRP)levels,and other observation indicators were analyzed after anesthesia intervention.Result:After the intervention,the analgesic effect and the evaluation results of the subjects in the experimental group were better than those in the control group(P<0.05);the obtained values of TNF-αand CRP levels in the experimental group were higher than those of the control group(P<0.05).Conclusion:The combined spinal-epidural anesthesia intervention demonstrated positive outcomes.The analgesic effect of patients during surgery and their inflammatory factor levels improved,which makes this intervention worthy of clinical application and promotion. 展开更多
关键词 Hip fracture in the elderly SURGERY Combined spinal and epidural anesthesia Analgesic effect TNF-Α CRP level
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Shao Yao Decoction exerts a protective effect on ulcerative colitis by inhibiting inflammation mediated by hypercoagulability
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作者 Huan-Tian Cui Yu-Ming wang ning wang 《Gastroenterology & Hepatology Research》 2024年第1期1-5,共5页
Background:Shaoyao decoction(SYD)has been found widespread clinical use in treating ulcerative colitis(UC).However,the mechanism underlying SYD impact on UC remains elusive.Materials and methods:We preliminarily evalu... Background:Shaoyao decoction(SYD)has been found widespread clinical use in treating ulcerative colitis(UC).However,the mechanism underlying SYD impact on UC remains elusive.Materials and methods:We preliminarily evaluated the therapeutic effect of SYD intervention in a dextran sulfate sodium-induced UC mouse model by analyzing the body weight change,disease activity index score,colon length,and HE staining results of colon tissue in each group of mice.Subsequently,we determined pro-inflammatory cytokines level and blood coagulation markers in the colon tissues of mice in each group to evaluate the effect of SYD intervention on colonic inflammatory response and coagulation function in UC mice.Results:Our findings emphasize the significant therapeutic effect of SYD on UC,including slowed down body weight loss,reduced disease activity index score,increased colon length,and reduced inflammatory infiltration in colon tissue.Moreover,SYD intervention significantly downregulated the levels of pro-inflammatory cytokines IL-1β,IL-6,and IL-17A in the colon.Furthermore,SYD intervention reversed the coagulation-related indicators such as prothrombin time,fibrinogen,P-selectin,D-dimer,and platelet glycomembrane protein IIb/IIIa.Conclusion:Our results elucidate the substantial therapeutic impact of SYD on UC mice.Importantly,the therapeutic mechanism of SYD in addressing UC potentially involves the inhibiting of inflammatory response mediated by hypercoagulability. 展开更多
关键词 shaoyao decoction ulcerative colitis HYPERCOAGULABILITY INFLAMMATION traditional Chinese medicine
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Serum containing Tongqiaohuoxue decoction suppresses glutamate-induced PC12 cell injury 被引量:8
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作者 ning wang Yi Dengt +2 位作者 Wei Wei Lihua Song Yan wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第15期1125-1131,共7页
Glutamate application is an established method of inducing PC12 cell injury. PC12 cells were cultured with serum containing Tongqiaohuoxue decoction consisting of moschus, Carthamus tinctorius, Rhizoma chuanxiong, Sem... Glutamate application is an established method of inducing PC12 cell injury. PC12 cells were cultured with serum containing Tongqiaohuoxue decoction consisting of moschus, Carthamus tinctorius, Rhizoma chuanxiong, Semen pruni persicae, and Radix Paeoniae Rubra. After 24 hours of co-cultivation, glutamate (12.5 mM) was added to the culture medium. We found that serum containing Tongqiaohuoxue decoction prevented the increase in reactive oxygen species, and the decreases in superoxide dismutase and Na+-K+-ATPase activity, induced by glutamate. It also reduced the concentration of malondialdehyde, enhanced the mitochondrial transmembrane potential, inhibited the elevation of cellular calcium, and decreased phosphorylation of calmodulin-dependent protein kinase II. Thus, serum containing Tongqiaohuoxue decoction had protective effects on cell proliferation and membrane permeability in glutamate-injured PC12 cells. 展开更多
关键词 PC12细胞 细胞损伤 谷氨酸 活血 诱导 血清 超氧化物歧化酶 ATP酶活性
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Tissue cell differentiation and multicellular evolution via cytoskeletal stiffening in mechanically stressed microenvironments 被引量:3
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作者 Junwei Chen ning wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第2期270-274,共5页
Evolution of eukaryotes from simple cells to complex multicellular organisms remains a mystery. Our postulate is that cytoskeletal stiffening is a necessary condition for evolution of complex multicellular organisms f... Evolution of eukaryotes from simple cells to complex multicellular organisms remains a mystery. Our postulate is that cytoskeletal stiffening is a necessary condition for evolution of complex multicellular organisms from early simple eukaryotes. Recent findings show that embryonic stem cells are as soft as primitive eukaryotes-amoebae and that differentiated tissue cells can be two orders of magnitude stiffer than embryonic stem cells. Soft embryonic stem cells become stiff as they differentiate into tissue cells of the complex multicellular organisms to match their microenvironment stiffness. We perhaps see in differentiation of embryonic stem cells (derived from inner cell mass cells) the echo of those early evolutionary events. Early soft unicellular organisms might have evolved to stiffen their cytoskeleton to protect their structural integrity from external mechanical stresses while being able to maintain form, to change shape, and to move. 展开更多
关键词 CYTOSKELETON Force Bacteria AMOEBAE EUKARYOTES
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Influence of Ultrasonic Surface Rolling Process and Shot Peening on Fretting Fatigue Performance of Ti-6Al-4V 被引量:3
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作者 ning wang Jinlong Zhu +3 位作者 Bai Liu Xiancheng Zhang Jiamin Zhang Shantung Tu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期63-75,共13页
At present,there are many studies on the residual stress field and plastic strain field introduced by surface strengthening,which can well hinder the initiation of early fatigue cracks and delay the propagation of fat... At present,there are many studies on the residual stress field and plastic strain field introduced by surface strengthening,which can well hinder the initiation of early fatigue cracks and delay the propagation of fatigue cracks.However,there are few studies on the effects of these key factors on fretting wear.In the paper,shot-peening(SP)and ultrasonic surface rolling process(USRP)were performed on Ti-6Al-4V plate specimens.The surface hardness and residual stresses of the material were tested by vickers indenter and X-ray diffraction residual stress analyzer.Microhardness were measured by HXD-1000MC/CD micro Vickers hardness tester.The effects of different surface strengthening on its fretting fatigue properties were verified by fretting fatigue experiments.The fretting fatigue fracture surface and wear morphology of the specimens were studied and analyzed by means of microscopic observation,and the mechanism of improving fretting fatigue life by surface strengthening process was further explained.After USRP treatment,the surface roughness of Ti-6Al-4V is significantly improved.In addition,the microhardness of the specimen after SP reaches the maximum at 80μm from the surface,which is about 123%higher than that of the AsR specimen.After USRP,it reaches the maximum at 150μm from the surface,which is about 128%higher than that of AsR specimen.It is also found that the residual compressive stress of the specimens treated by USRP and SP increases first and then decreases with the depth direction,and the residual stress reaches the maximum on the sub surface.The USRP specimen reaches the maximum value at 0.18 mm,about−550 MPa,while the SP specimen reaches the maximum value at 0.1 mm,about−380 MPa.The fretting fatigue life of Ti-6Al-4V effectively improved after USRP and SP.The surface integrity of specimens after USRP is the best,which has deeper residual compressive stress layer and more refined grain.In this paper,a fretting wear device is designed to carry out fretting fatigue experiments on specimens with different surface strengthening. 展开更多
关键词 TI-6AL-4V Fretting fatigue Residual stress Ultrasonic surface rolling process Surface strengthening
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Structural analysis of DMD gene and its clinical application in Chinese.Ⅰ. Bgl Ⅱ exon-containing fragment,RFLP and carrier detection
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作者 YU LONG ning wang +3 位作者 YU DENG YUMEIYANG SHENXING MURONG SHOUYUAN ZHAO(Institute of Genetics, National Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433,China)(Department of Neurology, Fujian Medical College,Fuzhou, China)(Correspon 《Cell Research》 SCIE CAS CSCD 1994年第2期201-215,共15页
This article is one of the serial studies oll the characteristics of the molecular structure for dystrophin gene in Chinese. By using the entire dystrophin cDNA (14 kb) as a probe- the number and RFLPs of Bgl Ⅱ exon-... This article is one of the serial studies oll the characteristics of the molecular structure for dystrophin gene in Chinese. By using the entire dystrophin cDNA (14 kb) as a probe- the number and RFLPs of Bgl Ⅱ exon-containing fragments of the dystrophin gene were analysed. Four new Bgl Ⅱ fragments were found, two of them (3.7 and 6.2 kb) detected by comparing the hybridization patterns with cDNA1-2a. 1a and 2a, one (9.3 kb) from the hybridization pattern with cDNA 9 by lengthening migrating distance of DNA fragments in electrophoresis. and another one (4.0 kb) by comparing the patterns with cDNA 11-14,11a- 11b’ 11c-12a and 14. The results indicated that the number of Bgl Ⅱ exon-containing fragments should be 59 rather than 55 reported previously, which laid the foundation of the Bgl Ⅱ partial restriction map for dystrophin gene. Three of the four RFLPs found in Caucacian appear in the hybridization patterns of three subclones, i.e.cDNA 2b-3. cDNA 4-5, and cDNA 5b-7.’ The values of expected heterozygote frequency (EHF) were 0.33, 0.33and 0.40 and the observed heterozygote frequency (OHF)were 0.40. 0.40 and 0.48 respectively. Meanwhile, two new rare allelic fragments (15 kb) were found in RFLPs from Bgl Ⅱ/2b-3 and Bgl Ⅱ/4-5a patterns respectively. These Bgl Ⅱ RFLPs and four XbaI RFLPs documented in our laboratory, have been used to detect the carrier in 7 DMDfamilies and 1 BMD family. Of the 69 individuals from the 8 families- 11 females were diagnosed as the carriers with DMD mutation, 4 females as the doubtful carriers, 12 females were defined as normal genotype and 2 females as probably normal. The results suggest that the carrier testing method based on dosage intensity analysis and genotype analysis by using dystrophin cDNA as a probe will be more sensitive and accurate. 展开更多
关键词 Bgl RFLP DMD基因 结构分析 中国人 临床意义 肌营养不良 含exon片断 检测
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Data mining-based model and risk prediction of colorectal cancer by using secondary health data:A systematic review
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作者 Hailun Liang Lei Yang +6 位作者 Lei Tao Leiyu Shi Wuyang Yang Jiawei Bai Da Zheng ning wang Jiafu Ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第2期242-251,共10页
Objective:Prevention and early detection of colorectal cancer(CRC)can increase the chances of successful treatment and reduce burden.Various data mining technologies have been utilized to strengthen the early detectio... Objective:Prevention and early detection of colorectal cancer(CRC)can increase the chances of successful treatment and reduce burden.Various data mining technologies have been utilized to strengthen the early detection of CRC in primary care.Evidence synthesis on the model’s effectiveness is scant.This systematic review synthesizes studies that examine the effect of data mining on improving risk prediction of CRC.Methods:The PRISMA framework guided the conduct of this study.We obtained papers via Pub Med,Cochrane Library,EMBASE and Google Scholar.Quality appraisal was performed using Downs and Black’s quality checklist.To evaluate the performance of included models,the values of specificity and sensitivity were comparted,the values of area under the curve(AUC)were plotted,and the median of overall AUC of included studies was computed.Results:A total of 316 studies were reviewed for full text.Seven articles were included.Included studies implement techniques including artificial neural networks,Bayesian networks and decision trees.Six articles reported the overall model accuracy.Overall,the median AUC is 0.8243[interquartile range(IQR):0.8050-0.8886].In the two articles that reported comparison results with traditional models,the data mining method performed better than the traditional models,with the best AUC improvement of 10.7%.Conclusions:The adoption of data mining technologies for CRC detection is at an early stage.Limited numbers of included articles and heterogeneity of those studies implied that more rigorous research is expected to further investigate the techniques’effects. 展开更多
关键词 Systematic review colorectal cancer disease detection data mining
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果园风送喷雾精准控制方法研究进展 被引量:61
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作者 翟长远 赵春江 +4 位作者 ning wang John Long 王 秀 Paul Weckler 张海辉 《农业工程学报》 EI CAS CSCD 北大核心 2018年第10期1-15,共15页
果园风送喷雾技术与装备正在朝着精准化和智能化方向发展。果园喷雾控制对象主要为喷施药量和风力供给量,二者需要协同精准调控,其按需调控的前提是果园靶标精准探测。该文从果园靶标探测方法、喷施药量控制方法、风力调控方法 3个方面... 果园风送喷雾技术与装备正在朝着精准化和智能化方向发展。果园喷雾控制对象主要为喷施药量和风力供给量,二者需要协同精准调控,其按需调控的前提是果园靶标精准探测。该文从果园靶标探测方法、喷施药量控制方法、风力调控方法 3个方面对现有研究进展进行综述,阐述了基于光电感知、超声波传感、激光雷达、图像、光谱和电子鼻技术探测果树位置、冠层外形轮廓、冠层体积、冠层内部结构、枝叶稠密程度、病虫害程度等特征信息的技术方法;分析了喷施药量调控方法中管道总药量控制方法在管道设计、混药方式、药液流量控制策略方面技术和产品化上取得的巨大突破,以及喷头药量独立控制方法研究方面获得的大量成果;综述了果园风送喷雾风速风量需求理论原则、风场雾场建模方法、风力调控方法与调控装备研究进展,指出了其基本理论原则、建模调控方法等科学问题还有待深入探索。同时,还分析了目前研究在果园靶标探测方法、喷施药量调控方法和风送喷雾风力调控方法中面临的困难和挑战,主要包括冠层稠密程度和病虫害程度高效感知方法探索、靶标风力需求普适模型构建、风场建模风力按需调控方法研究和精准喷雾技术与系统集成开发。最后指出了果园风送喷雾精准控制方法未来发展方向:1)果园靶标冠层枝叶稠密程度和病虫害程度在线探测方法将成为新的研究热点;2)果园风送喷雾风速风量供给需求理论原则、风场快速模拟仿真和风力调控方法与装备是未来重要研究方向;3)随着高新科技的涌现,科研院所和公司有望在果园喷雾药量和风力调控系统优化设计及精准喷雾机系统集成研发方面获得更大发展。 展开更多
关键词 农业机械 喷雾 果园 靶标探测 变量技术 风力调控
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基于地面激光雷达的田间花生冠层高度测量系统研制 被引量:21
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作者 程曼 蔡振江 +1 位作者 ning wang 袁洪波 《农业工程学报》 EI CAS CSCD 北大核心 2019年第1期180-187,共8页
在花生育种研究中对于冠层高度的获取主要依靠人工测量,不但费时费力,而且存在一定的主观性。为解决这一问题,该文构建了一个田间花生冠层高度特性表型信息获取系统,利用地面激光雷达Li DAR对花生冠层结构进行扫描,获取其三维点云数据;... 在花生育种研究中对于冠层高度的获取主要依靠人工测量,不但费时费力,而且存在一定的主观性。为解决这一问题,该文构建了一个田间花生冠层高度特性表型信息获取系统,利用地面激光雷达Li DAR对花生冠层结构进行扫描,获取其三维点云数据;采用多项式曲线拟合算法对点云数据进行分析,描绘冠层的大致轮廓并确定其边界,以得到目标冠层的有效数据集;通过对有效点云数据集生成的冠层高度矩阵分析,得到冠层的高度特性。试验结果表明,利用该系统获取的花生冠层平均高度与手工测量值最小偏差为2%,最大偏差为32%,最大偏差受地形影响和植株早期冠层本身的低高度所致,平均测量偏差约为11%,位于15%的可接受范围之内。该系统可以实现田间花生冠层高度信息的快速自动化获取,减少了人力成本的投入,该研究可为花生育种研究提供参考。 展开更多
关键词 作物 测量 图像处理 花生 冠层高度 LIDAR 田间测量
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金属气凝胶:可控制备与应用展望
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作者 王宁 李一 +4 位作者 崔乾 孙晓玥 胡悦 罗运军 杜然 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第9期69-98,共30页
作为多孔材料家族的最新成员之一,金属气凝胶(Metal aerogels,MAs)是完全由纳米结构金属构筑而成的一类新型气凝胶。MAs兼有金属独特的物理化学性质与气凝胶的结构特征,同时拥有高速传质通道、高导电性三维网络、自支撑性与独特的光学特... 作为多孔材料家族的最新成员之一,金属气凝胶(Metal aerogels,MAs)是完全由纳米结构金属构筑而成的一类新型气凝胶。MAs兼有金属独特的物理化学性质与气凝胶的结构特征,同时拥有高速传质通道、高导电性三维网络、自支撑性与独特的光学特性,故在电催化、表面增强拉曼散射和生物传感等领域均表现出卓越性能。然而,MAs的研究历史较短,其可控制备、构效关系探索等研究存在众多挑战性问题,距离商业化应用尚有较长的道路。因此,系统梳理MAs的研究工作,从中汲取经验与总结设计原理是极为有益的。本文将对MAs的合成策略、应用研究进行系统评述,在此基础上对本领域的挑战与机遇进行总结展望。希望招徕更多科研工作者,共同探索MAs这一年轻而前景广阔的新材料领域。 展开更多
关键词 气凝胶 金属 溶胶-凝胶 纳米结构 电催化
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从无障碍设施配置到友好环境营造——包容性大学校园规划设计探索 被引量:1
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作者 王宁 黄献明 《城市设计》 2023年第3期70-79,共10页
随着《中华人民共和国无障碍环境建设法》的正式实施,校园的无障碍环境建设将更多得到各级教育管理部门和办学机构的重视。“双一流”学科建设背景下,高校校园空间需要在实现无障碍要求的基础上,向更为友好和包容的方向发展。本文从包... 随着《中华人民共和国无障碍环境建设法》的正式实施,校园的无障碍环境建设将更多得到各级教育管理部门和办学机构的重视。“双一流”学科建设背景下,高校校园空间需要在实现无障碍要求的基础上,向更为友好和包容的方向发展。本文从包容性校园的服务对象、需求特征和性能目标3个方面的特殊性分析出发,结合康复大学、中国人民大学、北京科技大学等新校区案例实践,围绕校园无障碍系统性规划、精细化设计和多样化场景等内容,提出新时期大学校园包容性环境营造的策略与方法。 展开更多
关键词 无障碍 友好环境 包容性校园 系统性 精细化
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CPAL, as a New Mediator of Cardiomyocyte Metabolic Alterations and Pyroptosis, Regulates Myocardial Infarction Injury in Mice
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作者 Jiamin Li Hongru Xue +21 位作者 ning Xu Liling Gong Ming Li Sijia Li Di Huang Qingwei Zhang Pengyu Li Qingsui Li Hang Yu Yining Liu Yadong Xue Haixin Chen Jiali Liu Wanyu Zhang Mingbin Liu Siyu Chang Xianzhi Lang Xingmiao Zhao Weijie Du Benzhi Cai ning wang Baofeng Yang 《Engineering》 SCIE EI CAS CSCD 2023年第1期49-62,共14页
Myocardial infarction (MI), the most serious of the ischemic heart diseases, is accompanied by myocardial metabolic disorders and the loss of cardiomyocytes. Increasing evidence has shown that long noncoding RNAs (lnc... Myocardial infarction (MI), the most serious of the ischemic heart diseases, is accompanied by myocardial metabolic disorders and the loss of cardiomyocytes. Increasing evidence has shown that long noncoding RNAs (lncRNAs) are involved in various pathological conditions such as cancer and cardiovascular diseases (CVDs), and are emerging as a novel biomarker for these disorders. This study aims to investigate the regulatory role and mechanisms of lncRNAs in myocardial remodeling in the setting of MI. We find that post-infarcted hearts exhibit a reduction of adenosine triphosphate (ATP) and an alteration of the glucose and lipid metabolism genes cluster of differentiation 36 (CD36), hexokinase 1 (HK1), and clucose transporter 4 (GLUT4), accompanied by cardiomyocyte pyroptosis. We then identify a previously unknown conserved lncRNA, AK009126 (cardiomyocyte pyroptosis-associated lncRNA, CPAL), which is remarkably upregulated in the myocardial border zone of MI mice. Importantly, the adeno-associated virus 9 (AAV9)-mediated silencing of endogenous CPAL by its short hairpin RNA (shRNA) partially abrogates myocardial metabolic alterations and cardiomyocyte pyroptosis during MI in mice. Mechanistically, CPAL is shown to bind directly to nuclear factor kappa B (NFκB) and to act as an activator of NFκB to induce NFκB phosphorylation in cardiomyocytes. We also find that CPAL upregulates caspase-1 expression at the transcriptional level and consequently promotes the release of interleukin (IL)-18 and IL-1β from cardiomyocytes. Collectively, our findings reveal the conserved lncRNA CPAL as a new regulator of cardiac metabolic abnormalities and cardiomyocyte pyroptosis in the setting of MI and suggest CPAL as a new therapeutic target to protect cardiomyocytes against ischemic injury in infarcted hearts. 展开更多
关键词 Myocar dial infarction PYROPTOSIS CPAL NFKB Inflammation
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Hybrid absorbing boundary condition based on transmitting boundary and its application in 3D fractional viscoacoustic modeling
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作者 Song-Ling Li Ying Shi +2 位作者 ning wang Wei-Hong wang Xuan Ke 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期840-856,共17页
An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computa... An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computational cost and hardware capability limitations, numerical simulations are often performed within a finite domain. Thus, an adequate absorbing boundary condition (ABC) is indispensable for obtaining accurate numerical simulation results. In this study, we develop a hybrid ABC based on a transmitting boundary, which is referred to as THABC, to eliminate artificial boundary reflections in 3D second-order fractional viscoacoustic numerical simulations. Furthermore, we propose an adaptive weighted coefficient to reconcile the transmitting and viscoacoustic wavefields in THABC. Through several numerical examples, we determine that the proposed THABC approach is characterized by the following benefits. First, with the same number of absorbing layers, THABC exhibits a better ability in eliminating boundary reflection than traditional ABC schemes. Second, THABC is more effective in computation, since it only requires the wavefields at the current and last time steps to solve the transmitting formula within the absorbing layers. Benefiting from a simple but effective combination between the transmitting equation and the second-order wave equation, our scheme performs well in the 3D fractional Laplacian viscoacoustic numerical simulation. 展开更多
关键词 Hybrid absorbing boundary Numerical simulation Transmitting boundary Fractional viscoacoustic wave equation
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Power Consumption Characteristics Research on Mobile System of Electrically Driven Large-Load-Ratio Six-Legged Robot
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作者 Hongchao Zhuang ning wang +1 位作者 Haibo Gao Zongquan Deng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期237-267,共31页
The electrically driven large-load-ratio six-legged robot with engineering capability can be widely used in outdoor and planetary exploration.However,due to the particularity of its parallel structure,the effective ut... The electrically driven large-load-ratio six-legged robot with engineering capability can be widely used in outdoor and planetary exploration.However,due to the particularity of its parallel structure,the effective utilization rate of energy is not high,which has become an important obstacle to its practical application.To research the power consumption characteristics of robot mobile system is beneficial to speed up it toward practicability.Based on the configuration and walking modes of robot,the mathematical model of the power consumption of mobile system is set up.In view of the tripod gait is often selected for the six-legged robots,the simplified power consumption model of mobile system under the tripod gait is established by means of reducing the dimension of the robot’s statically indeterminate problem and constructing the equal force distribution.Then,the power consumption of robot mobile system is solved under different working conditions.The variable tendencies of the power consumption of robot mobile system are respectively obtained with changes in the rotational angles of hip joint and knee joint,body height,and span.The articulated rotational zones and the ranges of body height and span are determined under the lowest power consumption.According to the walking experiments of prototype,the variable tendencies of the average power consumption of robot mobile system are respectively acquired with changes in duty ratio,body height,and span.Then,the feasibility and correctness of theory analysis are verified in the power consumption of robot mobile system.The proposed analysis method in this paper can provide a reference on the lower power research of the large-load-ratio multi-legged robots. 展开更多
关键词 Electrically driven Large-load-ratio six-legged robot Power consumption Mobile system
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