期刊文献+
共找到24篇文章
< 1 2 >
每页显示 20 50 100
An improved analysis method for assessing the nuclear-heating impact on the stability of toroidal field magnets in fusion reactors
1
作者 Yu-Dong Lu Jin-Xing Zheng +7 位作者 Xu-Feng liu Huan Wu Jian Ge Kun Xu Ming Li hai-yang liu Lei Zhu Fei liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期163-176,共14页
The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin... The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T neutrons.This study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal hydraulics.In the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on stability.To enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the superconductor.This selection streamlines the workload associated with thermal-hydraulic analysis.This approach enables a more efficient and precise evaluation of the temperature margin of TF magnets.Moreover,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems. 展开更多
关键词 Superconducting magnet Nuclear heating NEUTRONICS Thermal hydraulics
下载PDF
Diabetes onset at an earlier age and high HbA1c levels as risk factors of diabetic retinopathy 被引量:9
2
作者 Rui-Fang Feng hai-yang liu +10 位作者 Ya-Lu liu Qing Xu Lei Qiao Chao-Ju Gong Yi-Peng Zhang Jie Li Li-Na Guan Wei Fan Mei-Li Li Wen-Jin Li Su-Yan Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第2期269-276,共8页
AIM:To assess the effect of age at diabetes onset and uncontrollable high Hb A1 c levels on the development of diabetic retinopathy(DR)among Chinese type 2 diabetes mellitus(DM)patients.METHODS:This was a cross-sectio... AIM:To assess the effect of age at diabetes onset and uncontrollable high Hb A1 c levels on the development of diabetic retinopathy(DR)among Chinese type 2 diabetes mellitus(DM)patients.METHODS:This was a cross-sectional survey of diabetic patients in Subei district,China.Data covering physical measurements,fasting blood-glucose(FBG),glycosylated hemoglobin(Hb A1 c),blood lipid,urinary albumin/creatinine ratio(UACR),ocular fundus examination,and diabetes treatment records were collected.An independent sample t-test were used to analyze differences.A Logistic regression analysis was applied to study the independent risk factors of DR.RESULTS:A total of 1282 patients with type 2 DM were enrolled,and 191 cases had DR(14.9%).The age at diabetes onset,education level,alcohol consumption,Hb A1 c level,UACR level,and hypoglycemic drugs were independent influencing factors for DR.The older the onset of diabetes,the less likely to develop DR(OR:0.958,95%CI:0.942-0.975,P=0.000).Patients were then divided in terms of age at diabetes onset as follows:<50 y,50-59 y,60-69 y,and≥70 y.Compared with diabetes onset age<50 y,50-59 y(OR:0.463,95%CI:0.306-0.699,P=0.000),60-69 y(OR:0.329,95%CI:0.203-0.535,P=0.000)and≥70 y(OR:0.232,95%CI:0.094-0.577,P=0.002)were at a lower risk of DR.The prevalence of DR was highest in patients with diabetes onset age<50 y(29.5%,P<0.05).The Hb A1 c level(8.67±1.97)%and proportion of insulin injection(52.5%)in patients with diabetes onset<40 y were higher than in patients with older diabetes onset age(P<0.05).CONCLUSION:Diabetes onset at an earlier age and uncontrollable high Hb A1 c level could be independent risk factors for DR. 展开更多
关键词 diabetic retinopathy age diabetes mellitus risk factors HBA1C
下载PDF
康柏西普联合25G玻璃体手术及小梁切除术治疗继发于PDR伴VH的NVG 被引量:7
3
作者 杨柳 李甦雁 +5 位作者 刘海洋 徐青 刘亚鲁 范巍 管莉娜 李婕 《国际眼科杂志》 CAS 北大核心 2020年第8期1399-1404,共6页
目的:比较不同围手术时期给予玻璃体腔内注射康柏西普联合25G微创玻璃体手术(PPV)及小梁切除术治疗继发于增生型糖尿病视网膜病变(PDR)伴玻璃体积血(VH)的新生血管性青光眼(NVG)的手术效果及并发症。方法:前瞻性随机对照临床试验。纳入2... 目的:比较不同围手术时期给予玻璃体腔内注射康柏西普联合25G微创玻璃体手术(PPV)及小梁切除术治疗继发于增生型糖尿病视网膜病变(PDR)伴玻璃体积血(VH)的新生血管性青光眼(NVG)的手术效果及并发症。方法:前瞻性随机对照临床试验。纳入2016-11/2019-04在我院确诊的PDR伴VH的Ⅲ期NVG患者28例30眼。所有患者均接受25G PPV联合小梁切除术。将其随机分为两组:第1组12例14眼患者于术前3d玻璃体腔内注射康柏西普,第2组16例16眼于25G玻璃体手术及小梁切除术毕玻璃体腔内注射康柏西普(IVC)0.5mg/0.05mL。比较两组患者手术时间、术中出血及术后并发症的发生率。观察术后疼痛缓解、虹膜新生血管(INV)消退和最佳矫正视力(BCVA)以及眼压(IOP)控制率情况。结果:第1、2组均完成手术并分别随访12.40±2.21mo和12.23±2.11mo(P>0.05)。第1组术中出血和术后早期前房出血发生率(29%、14%)低于第2组(75%、56%,均P<0.05)。两组患者手术时间、浅前房、脉络膜脱离、玻璃体再出血的发生率无差异(P>0.05)。术后3d所有患者疼痛缓解。第1组IVC后3d(即手术日)93%的INV完全消退,第2组PPV术后7d 94%INV完全消退。末次随访两组患者各有1眼残余少许萎缩的INV。术后1wk,1、3、6mo IOP控制率,第1组依次为93%、79%、64%、57%,第2组依次为94%、75%、50%、44%,两组患者各时间段比较无差异(P>0.05)。两组术后不同时间点IOP与术前相比均明显降低(P<0.05)。末次随访时第1、2组IOP分别为20.45±10.55和22.63±7.24mmHg,与术前42.21±9.11和44.88±11.83mmHg相比明显降低(P<0.05)。两组术后不同随访时间点BCVA与术前相比无差异(P>0.05)。结论:术前IVC预处理与术毕IVC联合25G PPV及小梁切除术治疗继发于PDR伴VH的NVG相比,术中出血和术后早期前房出血的发生率较低。两种方法IOP控制率相当,虽然随着时间逐渐减低,但是经过及时处理最终可以获得较好的疗效。 展开更多
关键词 康柏西普 新生血管性青光眼 增生型糖尿病视网膜病变 微创玻璃体切割术 小梁切除术
下载PDF
Ypsiyunnosides A-E,Five New Cholestanol Glycosides from Ypsilandra yunnanensis 被引量:6
4
作者 Yu Chen Yong-Ai Si +4 位作者 Wei Ni Huan Yan Xu-Jie Qin Chang-Xiang Chen hai-yang liu 《Natural Products and Bioprospecting》 CAS 2016年第3期173-182,共10页
Phytochemicalinvestigation onthe whole plants of Ypsilandra yunnanensiswas carried out forthe firsttime andledtothe isolation of five new cholestanol glycosides,ypsiyunnosides A–E(1–5),and one known analogue.Their s... Phytochemicalinvestigation onthe whole plants of Ypsilandra yunnanensiswas carried out forthe firsttime andledtothe isolation of five new cholestanol glycosides,ypsiyunnosides A–E(1–5),and one known analogue.Their structures were determined mainly by detailed spectroscopic analysis,including extensive 1D and 2D NMR,MS and UV,as well as chemical methods.Among them,compound 1 possessed a rare 6/6/6/5/5 fused-rings cholestanol sketelon,which was identified as(23R,25R)-3β,16α,26-triol-16,23-cyclocholest-5,17(20)-dien-22-one.Their induced platelet aggregation activities and cytotoxicities were evaluated.Graphical Abstract Five new cholestanol glycosides,ypsiyunnosides A–E(1–5),were isolated from the whole plants of Ypsilandra yunnanensis.Compound 1 possessed a rare 6/6/6/5/5 fused-rings cholestanol sketelon.Their structures were elucidated by a combination of 1D and 2D NMR,MS and chemical analysis. 展开更多
关键词 Ypsilandra yunnanensis LILIACEAE Cholestane glycoside Ypsiyunnosides A-E
下载PDF
Untiring Researches for Alternative Resources of Rhizoma Paridis 被引量:3
5
作者 Xu-Jie Qin Wei Ni +1 位作者 Chang-Xiang Chen hai-yang liu 《Natural Products and Bioprospecting》 CAS 2018年第4期265-278,共14页
Rhizoma Paridis(RP,M®),a traditional Chinese medicine,is the rhizoma of Paris polyphylla var.yunnanensis(PPY)or P.polyphylla var.chinensis which are widely used as important raw materials for several Chinese pate... Rhizoma Paridis(RP,M®),a traditional Chinese medicine,is the rhizoma of Paris polyphylla var.yunnanensis(PPY)or P.polyphylla var.chinensis which are widely used as important raw materials for several Chinese patent drugs.However,the wild resources of these herbs have become less and less due to their slow-growing characteristics and previously excessive excavation.This review covers untiring investigations on alternative resources of RP by our research group over the past decades,including non-medicinal parts of PPY as well as other plants of Liliaceae and Liliflorae families.The arial parts of PPY and the whole plants of Trillium kamtschaticum might be alternative resources for RP based on the fact that they shared the same or similar saponins and bioactivities. 展开更多
关键词 Rhizoma Paridis Paris polyphylla Alternative resources Steroidal saponins BIOACTIVITIES
下载PDF
Steroidal and pregnane glycosides from Ypsilandra thibetica 被引量:3
6
作者 hai-yang liu Chang-Xiang CHEN +2 位作者 Yi LU Jun-Yun YANG Wei NI 《Natural Products and Bioprospecting》 CAS 2012年第1期11-15,共5页
The whole plants of Ypsilandra thibetica have been analyzed as part of a systematic study on saponin constituents of medicinal plants.This has resulted in the isolation of two new bisdesmosidic furostanol saponins,nam... The whole plants of Ypsilandra thibetica have been analyzed as part of a systematic study on saponin constituents of medicinal plants.This has resulted in the isolation of two new bisdesmosidic furostanol saponins,named ypsilandroside P(1)and ypsilandroside Q(2),and one new pregnane glycoside,named ypsilandroside R(3),together with nine known steroidal glycosides.Their structures were elucidated on the basis of extensive spectroscopic analysis,including that of 2D NMR data,and the results of acidic hydrolysis.Ypsilandroside P(1)was cytotoxicity against two human tumor cell lines. 展开更多
关键词 Ypsilandra thibetica LILIACEAE furostanol glycoside pregnane glycoside ypsilandroside
下载PDF
Two New Highly Oxygenated Spirostanol Saponins from Paris polyphylla var.stenophylla 被引量:2
7
作者 Ling-Yu Jin Ting-Xiang Lu +6 位作者 Xu-Jie Qin Wei Ni Huan Yan Yu Chen Hui liu Hong-Ping He hai-yang liu 《Natural Products and Bioprospecting》 CAS 2016年第4期205-210,共6页
Phytochemical investigation of the rhizomes of Paris polyphylla var.stenophylla led to the isolation of two new highly oxygenated spirostanol saponins,named paristenosides A(1)and B(2),together with seven known compou... Phytochemical investigation of the rhizomes of Paris polyphylla var.stenophylla led to the isolation of two new highly oxygenated spirostanol saponins,named paristenosides A(1)and B(2),together with seven known compounds.Their structures were established mainly on the base of NMR spectroscopic techniques and mass spectrometry,as well as chemical methods.In addition,the cytotoxicity of the two new saponins was tested.Graphical Abstract Two new highly oxygenated spirostanol saponins,paristenosides A(1)and B(2),were isolated from the rhizomes of Paris polyphylla var.stenophylla.Their structures were established mainly based on NMR spectroscopic techniques and mass spectrometry,as well as chemical methods. 展开更多
关键词 Paris polyphylla var.stenophylla LILIACEAE Spirostanol saponins Paristenoside A Paristenoside B
下载PDF
Two New Steroidal Saponins from Ypsilandra thibetica 被引量:2
8
作者 Yong-Ai Si Huan Yan +4 位作者 Wei Ni Zhen-Hua liu Ting-Xiang Lu Chang-Xiang Cheng hai-yang liu 《Natural Products and Bioprospecting》 CAS 2014年第6期315-318,共4页
Two new monosaccharide steroidal saponins,named ypsilandroside S(1)and ypsilandroside T(2),have been isolated from the whole plants of Ypsilandra thibetica.Their structures were elucidated as heloniogenin 3-O-b-D-apio... Two new monosaccharide steroidal saponins,named ypsilandroside S(1)and ypsilandroside T(2),have been isolated from the whole plants of Ypsilandra thibetica.Their structures were elucidated as heloniogenin 3-O-b-D-apiofuranoside(1)and pregna 5,16-dien-3b,12a-diol-20-one-3-O-b-D-apiofuranoside(2)by spectroscopic techniques(1D and 2D NMR,MS).Compounds 1 and 2 were tested for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells. 展开更多
关键词 Ypsilandra thibetica LILIACEAE Ypsilandroside S Ypsilandroside T
下载PDF
Perioperative massive cerebral stroke in thoracic patients:Report of three cases 被引量:1
9
作者 Min-Yu Jian Fa Liang +1 位作者 hai-yang liu Ru-Quan Han 《World Journal of Clinical Cases》 SCIE 2021年第13期3170-3176,共7页
BACKGROUNDPerioperative stroke is a rare but devastating complication. The risk factors formassive cerebral stroke in surgical patients include older age, male sex, priorcerebrovascular disease, hypertension, renal fa... BACKGROUNDPerioperative stroke is a rare but devastating complication. The risk factors formassive cerebral stroke in surgical patients include older age, male sex, priorcerebrovascular disease, hypertension, renal failure, smoking, diabetes mellitus,and atrial fibrillation.CASE SUMMARYWe describe two cases of perioperative massive cerebral stroke following thoracicsurgery and one case following bronchoscopy. Neurologic symptoms, includingchanges in mental status and hemiplegia, occurred within 10 h after surgery in thethree patients. All three patients died after the surgery.CONCLUSIONPerioperative massive cerebral stroke may be more likely to occur in thoracicsurgical patients if there are pre-existing factors including previous stroke,hypotension, and hypoxemia. Sufficient pain control after surgery and timelyneurology consultation and management are helpful for the diagnosis and controlof stroke in high-risk patients. 展开更多
关键词 PERIOPERATIVE Massive cerebral stroke Thoracic surgery ANESTHESIA Literature review Case report
下载PDF
Structurally Diverse Polymethylated Phloroglucinol Meroterpenoids from Baeckea frutescens 被引量:1
10
作者 Yin-E Zhi Xu-Jie Qi +5 位作者 Hui liu Yuan Zeng Wei Ni Li He Zu-Ding Wang hai-yang liu 《Natural Products and Bioprospecting》 CAS 2018年第6期431-439,共9页
Phytochemical investigation of the MeOH extract of twigs and leaves of Baeckea frutescens led to the isolation of seven new polymethylated phloroglucinol meroterpenoids(PPMs),named baeckfrutones M-S(1-7).Their structu... Phytochemical investigation of the MeOH extract of twigs and leaves of Baeckea frutescens led to the isolation of seven new polymethylated phloroglucinol meroterpenoids(PPMs),named baeckfrutones M-S(1-7).Their structures and absolute configurations were determined by spectroscopic analyses,chiral-phase HPLC analysis,and electronic circular dichroism(ECD)calculations.PPM 1 is a novel meroterpenoid possessing a 6/6/5/3 tetracyclic skeleton in PPMs,whereas 3 and 4 are the first hydroxytasmanone type phloroglucinol-monoterpene hybrids.(+)-2 and 7 displayed potent antiinflammatory activity with IC50 values of 20.86±0.60 and 36.21±1.18 lL,respectively. 展开更多
关键词 Baeckea frutescens MYRTACEAE Polymethylated phloroglucinol meroterpenoids Anti-inflammatory activity
下载PDF
胸部肿瘤螺旋断层放疗系统setup功能位置矫正与误差来源分析
11
作者 徐士飞 冯欢 +2 位作者 刘海洋 胡杰 马露 《医学新知》 CAS 2022年第1期47-52,共6页
目的探讨螺旋断层放疗(helical tomotherapy,HT)系统setup功能矫正位置误差的作用并分析误差的来源。方法分析36例胸部肿瘤患者兆伏级计算机断层扫描图像信息,收集首次放疗常规复位和第二次放疗setup功能复位扫描的图像,并分别记录与千... 目的探讨螺旋断层放疗(helical tomotherapy,HT)系统setup功能矫正位置误差的作用并分析误差的来源。方法分析36例胸部肿瘤患者兆伏级计算机断层扫描图像信息,收集首次放疗常规复位和第二次放疗setup功能复位扫描的图像,并分别记录与千伏级计算机断层扫描图像配准的位置误差。比较2次复位误差间差异,构建重复测量混合线性回归模型分析可能的误差来源。结果除左右方向平移误差外,setup功能复位后误差均值总体上均小于首次复位,尤其在前后方向上,setup功能复位后误差显著小于首次复位(0.17±1.14 vs.5.04±2.43,P<0.001)。多因素分析发现,体质量指数(BMI)对胸部肿瘤前后方向平移误差和Roll旋转误差存在影响,回归系数β分别为0.191(P=0.001)和0.034(P=0.040)。此外,前后方向平移误差还受到分次剂量和治疗次数的影响。未发现性别、年龄和疾病类型对位置误差有明确影响。结论setup功能能够矫正位置误差,尤其前后方向平移误差。BMI、分次剂量和治疗次数影响胸部肿瘤放疗前后方向位置精准性。 展开更多
关键词 螺旋断层放疗系统 位置误差 setup功能 BMI
下载PDF
Terpenoids from Chloranthus elatior
12
作者 Chang-Li SUN Huan YAN +2 位作者 Xu-Hong LI Xue-Fang ZHENG hai-yang liu 《Natural Products and Bioprospecting》 CAS 2012年第4期156-159,共4页
Two new eudesmane-type sesquiterpenoid lactones,named chlorelactone A(1)and chlorelactone B(2),and one new labdane-type diterpenoid,named elatiorlabdane(3),along with seven known sesquiterpenoids and one known disesqu... Two new eudesmane-type sesquiterpenoid lactones,named chlorelactone A(1)and chlorelactone B(2),and one new labdane-type diterpenoid,named elatiorlabdane(3),along with seven known sesquiterpenoids and one known disesquiterpenoid were isolated from the whole plants of Chloranthus elatior.Their structures and relative configurations were established on the basis of extensive spectroscopic analysis. 展开更多
关键词 Chloranthus elatior CHLORANTHACEAE SESQUITERPENOID chlorelactone elatiorlabdane
下载PDF
Ypsilandrosides U-Y,five new steroidal saponins from Ypsilandra thibetica
13
作者 Wen-Tao Gao Ling-Ling Yu +5 位作者 Jing Xie Long-Gao Xiao Shi-Juan Zhang Wen-Yi Ma Huan Yan hai-yang liu 《Natural Products and Bioprospecting》 2022年第1期211-219,共9页
Phytochemical reinvestigation on the whole plants of Ypsilandra thibetica obtained four new spirostanol glycosides,named ypsilandrosides U-X(1-4),and one new cholestanol glycoside,named ypsilandroside Y(5).Their struc... Phytochemical reinvestigation on the whole plants of Ypsilandra thibetica obtained four new spirostanol glycosides,named ypsilandrosides U-X(1-4),and one new cholestanol glycoside,named ypsilandroside Y(5).Their structures have been established by extensive spectroscopic data and chemical methods.Among them,compound 4 is a rare spirostanol glycoside which possesses a novel 5(6→7)abeo-steroidal aglycone,while compound 1 is a first spiro-stanol bisdesmoside attached to C-3 and C-12,respectively,isolated from the genus Ypsilandra.The induced platelet aggregation activity of the isolates was tested. 展开更多
关键词 Ypsilandra thibetica Melanthiaceae Ypsilandrosides U-Y Spirostanol saponins Cholestanol saponins
下载PDF
Cytotoxic Acylphloroglucinol Derivatives from Callistemon salignus
14
作者 Xu-Jie Qin Tong Shu +7 位作者 Qian Yu Huan Yan Wei Ni Lin-Kun An Pan-Pan Li Yin-E Zhi Afsar Khan hai-yang liu 《Natural Products and Bioprospecting》 CAS 2017年第4期315-321,共7页
Callisalignenes G–I(1–3),three new meroterpenoids of b-triketone and monoterpene,along with two known analogues(4 and 5),were isolated from Callistemon salignus.Their structures and absolute configurations were unam... Callisalignenes G–I(1–3),three new meroterpenoids of b-triketone and monoterpene,along with two known analogues(4 and 5),were isolated from Callistemon salignus.Their structures and absolute configurations were unambiguously established by a combination of NMR and MS analysis and electronic circular dichroism(ECD)evidence.Callisalignenes H(2)and I(3)have a rare sec-butyl moiety at C-7.Meroterpenoids 1–3 exhibited cytotoxicity against HCT116 cells with IC50 values of 8.51±1.8,9.12±0.3,and 16.33±3.3 lM,respectively. 展开更多
关键词 Callistemon salignus MYRTACEAE MEROTERPENOIDS CYTOTOXICITY
下载PDF
Correction to:Structurally Diverse Polymethylated Phloroglucinol Meroterpenoids from Baeckea frutescens
15
作者 Yin-E Zhi Xu-Jie Qin +5 位作者 Hui liu Yuan Zeng Wei Ni Li He Zu-Ding Wang hai-yang liu 《Natural Products and Bioprospecting》 CAS 2019年第1期75-75,共1页
Correction to:Natural Products and Bioprospecting(2018)8:431–439 https://doi.org/10.1007/s13659-018-0189-3 In the original publication,two errors have occurred.The corrected texts are provided below:1.The author,Xu-J... Correction to:Natural Products and Bioprospecting(2018)8:431–439 https://doi.org/10.1007/s13659-018-0189-3 In the original publication,two errors have occurred.The corrected texts are provided below:1.The author,Xu-Jie Qi,should read as Xu-Jie Qin among the author group.2.The reference 9 should be cited as X.J.Qin,Y.E.Zhi,H.Yan,Y.Zhang,H.Liu,Q.Yu,S.Wang,Q.Zhao,L.He,X.Ma,L.K.An,H.Y.Liu,Tetrahedron 74,6658–6666(2018). 展开更多
关键词 PROSPECTING AMONG corrected
下载PDF
A sample of metal-poor galaxies identified from the LAMOST spectral survey
16
作者 Yu-Long Gao Jian-Hui Lian +8 位作者 Xu Kong Ze-Sen Lin Ning Hu hai-yang liu En-Ci Wang Zi-Huang Cao Yong-Hui Hou Yue-Fei Wang Yong Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第5期17-30,共14页
We present a sample of 48 metal-poor galaxies at z 〈 0.14 selected from 92 510 galaxies in the LAMOST survey. These galaxies are identified by their detection of the auroral emission line[OⅢ]λ4363 above the 3σ lev... We present a sample of 48 metal-poor galaxies at z 〈 0.14 selected from 92 510 galaxies in the LAMOST survey. These galaxies are identified by their detection of the auroral emission line[OⅢ]λ4363 above the 3σ level, which allows a direct measurement of electron temperature and oxygen abundance. The emission line fluxes are corrected for internal dust extinction using the Balmer decrement method. With electron temperature derived from [OⅢ]λλ4959, 5007/[OⅢ]λ4363 and electron density from [SⅡ]λ6731/[SⅡ]λ6717, we obtain the oxygen abundances in our sample which range from 12 + log(O/H) = 7.63(0.09 Z_⊙) to 8.46(0.6 Z_⊙). We find an extremely metal-poor galaxy with 12 + log(O/H) = 7.63 ± 0.01. With multiband photometric data from FUV to NIR and Hαmeasurements, we also determine the stellar masses and star formation rates, based on the spectral energy distribution fitting and Hα luminosity, respectively. We find that our galaxies have low and intermediate stellar masses with 6.39 ≤ log(M/M_⊙) ≤ 9.27, and high star formation rates(SFRs) with-2.18 ≤ log(SFR/M_⊙yr^(-1)) ≤ 1.95. We also find that the metallicities of our galaxies are consistent with the local T_e-based mass-metallicity relation, while the scatter is about 0.28 dex. Additionally,assuming the coefficient of α = 0.66, we find most of our galaxies follow the local mass-metallicity-SFR relation, but a scatter of about 0.24 dex exists, suggesting the mass-metallicity relation is weakly dependent on SFR for those metal-poor galaxies. 展开更多
关键词 galaxies: abundances -- galaxies: evolution -- galaxies: starburst -- star formation
下载PDF
Risk assessment of malignancy in solitary pulmonary nodules in lung computed tomography:a multivariable predictive model study 被引量:8
17
作者 hai-yang liu Xing-Ru Zhao +7 位作者 Meng Chi Xiang-Song Cheng Zi-Qi Wang Zhi-Wei Xu Yong-Li Li Rui Yang Yong-Jun Wu Xiao-Ju Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2021年第14期1687-1694,共8页
Background:Computed tomography images are easy to misjudge because of their complexity,especially images of solitary pulmonary nodules,of which diagnosis as benign or malignant is extremely important in lung cancer tr... Background:Computed tomography images are easy to misjudge because of their complexity,especially images of solitary pulmonary nodules,of which diagnosis as benign or malignant is extremely important in lung cancer treatment.Therefore,there is an urgent need for a more effective strategy in lung cancer diagnosis.In our study,we aimed to externally validate and revise the Mayo model,and a new model was established.Methods:A total of 1450 patients from three centers with solitary pulmonary nodules who underwent surgery were included in the study and were divided into training,internal validation,and external validation sets(n=849,365,and 236,respectively).External verification and recalibration of the Mayo model and establishment of new logistic regression model were performed on the training set.Overall performance of each model was evaluated using area under receiver operating characteristic curve(AUC).Finally,the model validation was completed on the validation data set.Results:The AUC of the Mayo model on the training set was 0.653(95%confidence interval[CI]:0.613–0.694).After re-estimation of the coefficients of all covariates included in the original Mayo model,the revised Mayo model achieved an AUC of 0.671(95%CI:0.635–0.706).We then developed a new model that achieved a higher AUC of 0.891(95%CI:0.865–0.917).It had an AUC of 0.888(95%CI:0.842–0.934)on the internal validation set,which was significantly higher than that of the revised Mayo model(AUC:0.577,95%CI:0.509–0.646)and the Mayo model(AUC:0.609,95%CI,0.544–0.675)(P<0.001).The AUC of the new model was 0.876(95%CI:0.831–0.920)on the external verification set,which was higher than the corresponding value of the Mayo model(AUC:0.705,95%CI:0.639–0.772)and revised Mayo model(AUC:0.706,95%CI:0.640–0.772)(P<0.001).Then the prediction model was presented as a nomogram,which is easier to generalize.Conclusions:After external verification and recalibration of the Mayo model,the results show that they are not suitable for the prediction of malignant pulmonary nodules in the Chinese population.Therefore,a new model was established by a backward stepwise process.The new model was constructed to rapidly discriminate benign from malignant pulmonary nodules,which could achieve accurate diagnosis of potential patients with lung cancer. 展开更多
关键词 CT image Lung cancer Prediction model Pulmonary nodules Regression algorithm
原文传递
High-mobility patternable MoS_(2) percolating nanofilms 被引量:3
18
作者 Xiangxiang Gao Jun Yin +4 位作者 Gang Bian hai-yang liu Chao-Peng Wang Xi-Xi Pang Jian Zhu 《Nano Research》 SCIE EI CSCD 2021年第7期2255-2263,共9页
Fabrication of large-area and uniform semiconducting thin films of two-dimensional(2D)materials is paramount for the full exploitation of their atomic thicknesses and smooth surfaces in integrated circuits.In addition... Fabrication of large-area and uniform semiconducting thin films of two-dimensional(2D)materials is paramount for the full exploitation of their atomic thicknesses and smooth surfaces in integrated circuits.In addition to elaborate vapor-based synthesis techniques for the wafer-scale growth of 2D films,solution-based approaches for high-quality thin films from the liquid dispersions of 2D flakes,despite underdeveloped,are alternative cost-effective tactics.Here,we present layer-by-layer(LbL)assembly as an effective approach to obtaining scalable semiconducting films of molybdenum disulfide(MoS_(2))for field-effect transistors(FETs).LbL assembly is achieved by coordinating electrochemically exfoliated MoS_(2) with cationic poly(diallyldimethylammonium chloride)(PDDA)through electrostatic interactions.The PDDA/MoS_(2) percolating nanofilms show controlled and self-limited growth on a variety of substrates,and are easily patterned through lift-off processes.Ion gel gated FETs are fabricated on these MoS_(2) nanofilms,and they show mobilities of 9.8 cm^(2)·V^(−1)·s^(−1),on/off ratios of 2.1×10^(5) with operating voltages less than 2 V.The annealing temperature in the fabrication process can be as low as 200℃,thereby permitting the fabrication of flexible FETs on polyethylene terephthalate substrates.The LbL assembly technique holds great promise for the large-scale fabrication of flexible electronics based on solution-processed 2D semiconductors. 展开更多
关键词 layer-by-layer assembly molybdenum disulfide NANOFILMS solution-processed electronics field-effect transistors
原文传递
β-Octafluorinated tetrakis(ethoxycarbonyl)porphyrin 被引量:2
19
作者 Hua-Hua Wang Yi-Yu Jiang +4 位作者 Mian HR Mahmood hai-yang liu Herman H.Y.Sung Ian D.Williams Chi K.Chang 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第5期529-533,共5页
Tetrakis(alkoxycarbonyl)porphyrin and its β-octafluoro-substituted derivatives were synthesized via Lindsey method and transformed to their zinc complexes. Single crystal X-ray structures of corresponding Zn(II) ... Tetrakis(alkoxycarbonyl)porphyrin and its β-octafluoro-substituted derivatives were synthesized via Lindsey method and transformed to their zinc complexes. Single crystal X-ray structures of corresponding Zn(II) porphyrins revealed that β-octafluorination will give more compactness of porphyrin moieties in the crystal structure owing to the hydrogen bonding interactions involving β- fluorine atoms. An unusual six-coordinated Zn(II) was found via intramolecular coordination of oxygen atom of meso-substituents with central Zn(II). 展开更多
关键词 Tetraalkyl porphyrin Zinc Ethyl glyoxylate 3 4-Difluoropyrrole
原文传递
Appended corrole manganese complexes:Catalysis and axial-ligand effect 被引量:3
20
作者 Nga-Chun Ng Mian HR Mahmood +3 位作者 Chi-K.Chang hai-yang liu Fei Yam Lam-Lung Yeung 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第4期571-574,共4页
A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated b... A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated by spectroscopy. Kinetic studies indicated that the presence of appended N- donor ligands may cause a significant enhancement of the rate of oxygen atom transfers (OAT) from (oxo)manganese(V) corrole to alkene, and the stronger axial ligand binding has impact on the rate of the oxidation reaction. Turnover frequency (TOF) for the catalytic oxidation of alkenes by appended manganese corroles varies with the following ligand order: acetamido 〈 pyridyl 〈 imidazolyl. The influence of the external axial ligands on the catalytic epoxidation was investigated by using appended acetamido manganese corrole as catalyst, with the results revealing that N-methylimidazole gave the best enhancement on the yields of total oxidation products among the investigated nitrogenous ligands. 展开更多
关键词 Manganese Corrole Catalysis Axial-ligand Oxygen atom transfer
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部