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新护士生涯适应力对其转型冲击的影响 被引量:23
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作者 罗兰 刘思维 +1 位作者 陈阳广 吴艳平 《中华现代护理杂志》 2016年第21期2971-2974,共4页
目的:探讨新护士生涯适应力对其转型冲击的影响。方法采用《生涯适应力量表》及《新护士转型冲击量表》对湖南省6家三级甲等医院223名新护士进行问卷调查,了解新护士生涯适应力及转型冲击的现状,分析两者之间的关系。结果在新护士生... 目的:探讨新护士生涯适应力对其转型冲击的影响。方法采用《生涯适应力量表》及《新护士转型冲击量表》对湖南省6家三级甲等医院223名新护士进行问卷调查,了解新护士生涯适应力及转型冲击的现状,分析两者之间的关系。结果在新护士生涯适应力中,生涯信心维度均分最高为(3.61±0.53)分,生涯控制维度均分最低为(3.29±0.74)分;而转型冲击中,身体维度均分最高为(3.72±0.84)分,社会文化与发展维度均分最低为(3.24±0.76)分。进一步研究发现,新护士生涯适应力各维度与转型冲击各维度得分呈负相关(r值分别为-0.440,-0.224,-0.258,-0.238;P〈0.05)。多元逐步回归分析显示,新护士生涯关注、生涯控制、生涯好奇、生涯信心为转型冲击的影响因素。结论医院管理者尤其要注重关注新护士的生涯关注力和生涯控制力,采取针对性措施提高新护士生涯适应力水平,使其顺利完成角色转变,稳定护理队伍,进一步提高医院护理质量。 展开更多
关键词 新护士 生涯适应力 转型冲击 newly graduated nurses(NGRNs)
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Geochemistry of the high-Mg andesites at Zhangwu, western Liaoning: Implication for delamination of newly formed lower crust 被引量:20
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作者 HUANG Hua1,GAO Shan1,2,HU ZhaoChu1,LIU XiaoMing2 & YUAN HongLing2 1 State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China 2 State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China 《Science China Earth Sciences》 SCIE EI CAS 2007年第12期1773-1786,共14页
Ten volcanic samples at Zhangwu,western Liaoning Province,North China were selected for a sys-tematic geochemical,mineralogical and geochronological study,which provides an opportunity to ex-plore the interaction betw... Ten volcanic samples at Zhangwu,western Liaoning Province,North China were selected for a sys-tematic geochemical,mineralogical and geochronological study,which provides an opportunity to ex-plore the interaction between the continental crust and mantle beneath the north margin of the North China craton.Except one basalt sample(SiO2= 50.23%),the other nine samples are andesitic with SiO2 contents ranging from 53% to 59%.They have relatively high MgO(3.4%―6.1%,Mg#=50―64) and Ni and Cr contents(Ni 27×10?6―197×10?6,Cr 51×10?6―478×10?6).Other geochemical characteristics of Zhangwu high-Mg andesites(HMAs) include strong fractionation of light rare earth elements(LREE) from heavy rare earth elements(HREE),and Sr from Y,with La/Yb greater than 15,and high Sr/Y(34― 115).Zircons of andesite YX270 yield three age groups with no Precambrian age,which precludes ori-gin of the Zhangwu HMAs from the partial melting of the Precambrian crust.The oldest age group peaking at 253 Ma is interpreted to represent the collision of the Siberia block and the North China block,resulting in formation of the Central Asian orogenic belt by closure of the Mongol-Okhotsk Ocean.The intermediate age group corresponds to the basalt underplating which caused the wide-spread coeval granitoids in the North China craton with a peak 206Pb/238U age of 172 Ma.The youngest age group gives a 206Pb/238U age of 126±2 Ma,which is interpreted as the eruption age of the Zhangwu HMAs.The high 87Sr/86Sri(126 Ma)>0.706 and low εNd(t)= ?6.36―?13.99 of the Zhangwu HMAs are distinct from slab melts.The common presence of reversely zoned clinopyroxene phenocrysts in the Zhangwu HMAs argues against the origin of the Zhangwu HMAs either from melting of the water saturated mantle or melting of the lower crust.In light of the evidence mentioned above,the envisaged scenario for the formation of the Zhangwu HMAs is related to the basaltic underplating at the base of the crust,which led to the thickening of the lower crust and formation of lower crustal ec 展开更多
关键词 Zhangwu HMAs BASALT underplating newly FORMED lower crust delamination North China CRATON
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A Comparative miRNAome Analysis Reveals Seven Fiber Initiation-Related and 36 Novel miRNAs in Developing Cotton Ovules 被引量:16
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作者 Zheng-Ming Wang Wei Xue +5 位作者 Chun-Juan Dong Long-Guo Jin Shao-Min Bian Chuan Wang Xiu-Yun Wu Jin-Yuan Liu 《Molecular Plant》 SCIE CAS CSCD 2012年第4期889-900,共12页
An increasing number of microRNAs (miRNAs) have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to chara... An increasing number of microRNAs (miRNAs) have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to characterize miRNAomes from the ovules of wild-type upland cotton and a fiberless mutant during fiber initiation. Comparative miR- NAome analysis combined with northern blotting and RACE-PCR revealed seven fiber initiation-related miRNAs expressed in cotton ovules and experimentally validated targets of these miRNAs are involved in different cellular responses and metabolic processes, including transcriptional regulation, auxin and gibberellin signal transduction, actin bundles, and lignin biosynthesis. This paper describes a complex regulatory network consisting of these miRNAs expressed in cotton ovules to coordinate fiber initiation responses. In addition, 36 novel miRNAs and two conserved miRNAs were newly iden- tified, nearly doubling the number of known cotton miRNA families to a total of 78. Furthermore, a chromatin remodeling complex subunit and a pre-mRNA splicing factor are shown for the first time to be miRNA targets. To our knowledge, this study is the first systematic investigation of fiber initiation-related miRNAs and their targets in the developing cotton ovule, deepening our understanding of the important regulatory functions of miRNAs in cotton fiber initiation. 展开更多
关键词 Cotton ovules fiber initiation high-throughput sequencing molecular characterization newly identifiedmiRNAs.
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Dietary supplementation of xylanase and protease on growth performance,digesta viscosity,nutrient digestibility,immune and oxidative stress status,and gut health of newly weaned pigs 被引量:12
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作者 Marcos E.Duarte Fang X.Zhou +1 位作者 Wilson M.Dutra Jr. Sung Woo Kim 《Animal Nutrition》 SCIE 2019年第4期351-358,共8页
This study was to investigate the effect of dietary supplementation with xylanase and protease on growth performance,digesta viscosity,apparent ileal digestibility(AID) of nutrients,and gut health in nursery pigs.Fort... This study was to investigate the effect of dietary supplementation with xylanase and protease on growth performance,digesta viscosity,apparent ileal digestibility(AID) of nutrients,and gut health in nursery pigs.Forty-eight pigs(24 barrows and 24 gilts at 21 d of age with 7.2±0.4 kg BW) were randomly allotted to 4 dietary treatments(2 x 2 factorial arrangement) in a randomized complete block design and fed in 2 phases(phase 1 for 10 d and phase 2 for 14 d).Factors were xylanase(0 or45,000 XU/kg) and protease(0 or 300,000 U/kg).Feed intake and BW gain were measured on d 10 and24.Titanium dioxide(0.25%) was added to all diets as an indigestible external marker from d 20 to 24.On d 24,all pigs were euthanized to obtain jejunal and ileal digesta to measure viscosity and apparent ileal digestibility.The jejunal mucosa was collected to measure immune and oxidative stress status.Jejunal tissues were used to measure morphology and crypt cells proliferation.In phase 2,xylanase increased(P <0.05) the average daily gain(ADG) which was further increased(P <0.05) when combined with protease.Overall,combinational use of xylanase and protease increased(P <0.05) ADG compared with the use of xylanase or protease alone,whereas protease improved(P <0.05) feed efficiency.In jejunum,xylanase reduced(P <0.05) viscosity of digesta,mucosal malondialdehyde(MDA),crypt depth and crypt cells proliferation,and protease increased(P <0.05) villus height,and decreased(P <0.05) crypt depth and crypt cells proliferation.Collectively,xylanase improved growth performance,digesta viscosity,and oxidative stress,whereas protease improved feed efficiency and gut morphology.The combinational use of xylanase and protease enhanced growth performance of newly weaned pigs. 展开更多
关键词 Growth performance GUT health newly weaned PIGS Viscosity PROTEASE XYLANASE
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Fragmentation Energy-Saving Theory of Full Face Rock Tunnel Boring Machine Disc Cutters 被引量:12
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作者 Zhao-Huang Zhang Guo-Fang Gong +1 位作者 Qing-Feng Gao Fei Sun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期913-919,共7页
Attempts to minimize energy consumption of a tunnel boring machine disc cutter during the process of fragmentation have largely focused on optimizing disc- cutter spacing, as determined by the minimum specific energy ... Attempts to minimize energy consumption of a tunnel boring machine disc cutter during the process of fragmentation have largely focused on optimizing disc- cutter spacing, as determined by the minimum specific energy required for fragmentation; however, indentation tests showed that rock deforms plastically beneath the cutters. Equations for thrust were developed for both the traditional, popularly employed disc cutter and anew design based on three-dimensional theory. The respective energy consumption for penetration, rolling, and side-slip fragmentations were obtained. A change in disc-cutter fragmentation angles resulted in a change in the nature of the interaction between the cutter and rock, which lowered the specific energy of fragmentation. During actual field excavations to the same penetration length, the combined energy consumption for fragmentation using the newly designed cutters was 15% lower than that when using the traditional design. This paper presents a theory for energy saving in tunnel boring machines. Investigation results showed that the disc cutters designed using this theory were more durable than traditional designs, and effectively lowered the energy consumption. 展开更多
关键词 newly design Disc cutter FRAGMENTATION Specific energy Energy consumption
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基于心理授权的培训模式对新毕业护士工作胜任力的影响 被引量:13
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作者 沈月 孙璇 万永慧 《现代临床护理》 2018年第7期57-61,共5页
目的探讨基于心理授权的培训模式对提高新毕业护士工作胜任力的效果。方法将2016年本院入职的221名新毕业护士设为对照组,在培训中采用理论授课和专科操作培训;将2017年本院入职的219名新毕业护士设为观察组,采用基于心理授权的培训模... 目的探讨基于心理授权的培训模式对提高新毕业护士工作胜任力的效果。方法将2016年本院入职的221名新毕业护士设为对照组,在培训中采用理论授课和专科操作培训;将2017年本院入职的219名新毕业护士设为观察组,采用基于心理授权的培训模式进行干预,两组培训时间均为6个月。培训前后对两组新毕业护士的心理授权水平和胜任力进行测评和比较。结果培训后,观察组新毕业护士心理授权总分与工作胜任力总分均高于对照组,两组比较,差异均有统计学意义(P<0.05)。结论基于心理授权的培训模式能有效提高新毕业护士的心理授权水平,最终达到提升新毕业护士胜任力,对新毕业护士完成角色转变起到促进作用。 展开更多
关键词 新毕业 护士 心理授权 护士胜任力
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Newly onset indirect traumatic optic neuropathy-surgical treatment first versus steroid treatment first 被引量:11
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作者 Bo Yu Ying-Jie Ma +1 位作者 Yun-Hai Tu Wen-Can Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第1期124-128,共5页
AIM: To investigate the efficacy and safety of the treatment of endoscopic trans-ethmosphenoid optic canal decompression(ETOCD) with combination of steroid in patients with newly onset indirect traumatic optic neuropa... AIM: To investigate the efficacy and safety of the treatment of endoscopic trans-ethmosphenoid optic canal decompression(ETOCD) with combination of steroid in patients with newly onset indirect traumatic optic neuropathy(ITON) and compare the outcome between immediate ETOCD treatment and ETOCD with preoperative steroid treatment. METHODS: Patients presented as newly onset ITON(suffered trauma within 3 d) at a tertiary medical center between Mar 1 st, 2016 and Mar 1 st, 2018 were enrolled in this study. All patients were equally and randomly divided into 2 groups. Cases in group A were performed ETOCD immediately after admition while cases in group B were prescribed by methylprednisolone(20 mg/kg · d) for 3 d before ETOCD. Methylprednisolone(20 mg/kg · d) was used after surgery for 6 d in group A and 3 d in group B. Follow-up was up to 3 mo in all cases. Visual acuity(VA) before and after treatment between the two groups were taken into comparison. RESULTS: Complete postoperative data were acquired from 34 patients in group A and from 32 patients in group B. Group A had significantly higher effective rate in VA than group B(χ~2 =4.905, P=0.027).CONCLUSION: For patients with newly onset ITON, combination treatment of ETOCD with high-dose steroid is an effective and safe way. Immediate surgery will lead to better prognosis for these cases. 展开更多
关键词 indirect traumatic optic neuropathy endoscopic trans-ethmosphenoid optic canal decompression STEROID visual acuity newly onset
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Serum uric acid level in newly diagnosed essential hypertension in a Nepalese population:A hospital based cross sectional study 被引量:10
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作者 Bibek Poudel Binod Kumar Yadav +2 位作者 Arun Kumar Bharat Jha Kanak Bahadur Raut 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第1期59-64,共6页
Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hyperten... Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hypertension was defined according to blood pressure readings by definitions of the Seventh Report of the Joint National Committee.Totally 205newly diagnosed and untreated essential hypertensive cases and age-sex matched nonnotensive controls were enrolled in the study.The potential confounding factors of hyperuricemia and hypertension in both cases and controls were controlled.Uric acid levels in all participants were analyzed.Results:Renal function between newly diagnosed hypertensive cases and nonnotensive healthy controls were adjusted.The mean serum uric acid observed in newly diagnosed hypertensive cases and in nonnotensive healthy controls were(290.05±87.03)μmol/L and(245.24±09.38)μmol/L respectively.A total of 59(28.8%)participants of cases and 28(13.7%)participants of controls had hyperuricemia(odds ratio 2.555(95%CI:1.549-4.213),P<0.00l).Conclusions:The mean serum uric acid leveb and number of hyperuricemic subjects were found to be significantly higher in cases when compared to controls. 展开更多
关键词 newly diagnosed HYPERTENSION SERUM uric acid HYPERURICEMIA Joint National COMMITTEE
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Correlation analysis of internal jugular vein abnormalities and cerebral venous sinus thrombosis 被引量:9
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作者 JIA Ling-yun HUA Yang +1 位作者 JI Xun-ming LIU Jiang-tao 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第20期3671-3674,共4页
Background Cerebral venous sinus thrombosis (CVST) is a special form of stroke with multiple causes and risk factors. However, there are still a portion of cases with unknown reasons. The aim of this study was to in... Background Cerebral venous sinus thrombosis (CVST) is a special form of stroke with multiple causes and risk factors. However, there are still a portion of cases with unknown reasons. The aim of this study was to investigate the relationship between internal jugular vein (IJV) abnormalities and the development of CVST. Methods A total of 51 CVST patients and 30 healthy controls were enrolled. The diameter, the maximum velocity (Vmax) and the reflux time in bilateral IJVs were measured by color Doppler flow imaging (CDFI). The paired t test was used to compare the numeric values between the bilateral IJVs. The Pearson chi-square test was used to evaluate the relationship between IJV abnormality and CVST, IJV abnormality and IJV reflux, respectively. Results Among the 51 CVST patients, 20 (39%) patients were with normal IJV and 31 (61%) patients were with abnormal IJV. The types of IJV abnormality included annulus stenosis 19 cases (61%), hypoplasia 9 cases (29%), thrombosis 2 cases (7%) and anomalous valve 1 case (3%). In patients with unilateral IJV abnormality, the minimum diameter of the IJV on the lesion side was significantly smaller than that of the contralateral side (P 〈0.0001). When compared with contralateral side, the Vmax of the lesion side with unilateral annulus stenosis was significant higher, however, it was obvious lower in patients with unilateral hypoplasia (P 〈0.05). Furthermore, among 27 cases with unilateral IJV abnormality, all the CYST occurred on the same side as the IJV lesions. 展开更多
关键词 IJV abnormality closely correlated with the development of CVST which is a newly identified risk factor forCVST.
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A Preliminary Study on Geological and Seismogenic Structures in the Region of 1969 M 7.4 Bohai Sea Earthquake 被引量:8
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作者 Xu Jie, Gao Zhanwu, Sun Jianbao, and Song ChangqingInstitute of Geology, China Seismological Bureau, Beijing 100029, China 《Earthquake Research in China》 2001年第4期365-379,共15页
A more detailed and deep-going analysis of tectonic conditions for the 1989 Bohai Sea M 7.4 earthquake area has been made based on the data of oil geological exploration and results of seismological researches. The ob... A more detailed and deep-going analysis of tectonic conditions for the 1989 Bohai Sea M 7.4 earthquake area has been made based on the data of oil geological exploration and results of seismological researches. The obtained result fills the gap in seismotectonic research of Large Bohai Sea earthquake area of North China. The earthquake area is located in the eastern part of Cenozoic rifted basin of the Bohai Gulf, along the intersection zone between the NNE-trending Yingkou-Weifang fault zone and the NW-trending Beijing-Penglai fault zone. In the early-Tertiary fault-depression stage, three sets of faults, the NNE-, NW-, and W-E-trending faults, were developed in the upper crust in the area. They are listric and planar in the form, of normal fault character and mostly the major faults in faulted depressions. In the fault-depression stage since late Tertiary, the preexisting faults have undergone movement to different extent. Meanwhile, a new NE-trending Huanghekou (Yellow River Mouth)-Miaoxibei fault zone was developed. The focal faulting of the M 7.4 earthquake, striking to N45°E and dipping to SE, is nearly vertical, with dextral strike-slip nature, and buried down to depth of 15~34 km. The seismogenic fault for the large earthquake is not the Yingwei fault, but the newly generated Huanghekou-Miaoxibei fault. 展开更多
关键词 Bohai GULF basin Bohai Sea Ms7.4 EARTHQUAKE newly generated FAULT zone LIS tric FAULT
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A Single-Frequency Linearly Polarized Fiber Laser Using a Newly Developed Heavily Tm3+-Doped Germanate Glass Fiber at 1.95 μm 被引量:8
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作者 杨麒 徐善辉 +5 位作者 李灿 杨昌盛 冯洲明 肖瑜 黄湘 杨中民 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期62-65,共4页
A compact linearly polarized, low-noise, narrow-linewidth, single-frequency fiber laser at 1950nm is demonstrated. This compact fiber laser is based on a 21-mm-long homemade Tm3+-doped germanate glass fiber. Over 100... A compact linearly polarized, low-noise, narrow-linewidth, single-frequency fiber laser at 1950nm is demonstrated. This compact fiber laser is based on a 21-mm-long homemade Tm3+-doped germanate glass fiber. Over 100-mW stable continuous-wave single transverse and longitudinal mode lasing at 195Ohm are achieved. The measured relative intensity noise is less than -135dB/Hz at frequencies over 5 MHz. The signal-to-noise ratio of the laser is larger than 72dB, and the laser linewidth is less than 6kHz, while the obtained linear polarization extinction ratio is higher than 22 dB. 展开更多
关键词 FBG Doped Germanate Glass Fiber at 1.95 DBR kHz RIN A Single-Frequency Linearly Polarized Fiber Laser Using a newly Developed Heavily Tm
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Report of Prionospio complex(Annelida:Polychaeta:Spio-nidae) from China's waters,with description of a new species 被引量:6
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作者 ZHOU Jin LI Xinzheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第1期116-127,共12页
Nine species of Prionospio complex are recorded from China's waters,including one new species and six newly recorded species.Prionospio(Prionospio) pacifica sp.nov.,is characterized by having first and forth pairs ... Nine species of Prionospio complex are recorded from China's waters,including one new species and six newly recorded species.Prionospio(Prionospio) pacifica sp.nov.,is characterized by having first and forth pairs of branchiae pinnate,second and third pairs of apinnate,ventral crest on Setiger 9 and dorsal crests on Setigers 10-25.Apoprionospio kirrae(Wilson,1990),Prionospio(Aquilaspio) convexa Imajima,1990,Prionospio(Minuspio) multibranchiata Berkeley,1927,Prionospio(Prionospio) bocki Sderstrm,1920,Prionospio(Prionospio) dubia Maciolek,1985 and Prionospio(Prionospio) paradisea Imajima,1990 are recorded for the first time from China's waters. 展开更多
关键词 taxonomy Prionospio complex new species newly recorded species China's waters.
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Application of nanotechnology in a silver/graphite contact material and optimization of its physical and mechanical properties 被引量:5
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作者 YUHaifeng LEIJingxuan +4 位作者 MAXueming ZHULihui LUYao XIANGJing WENGWei 《Rare Metals》 SCIE EI CAS CSCD 2004年第1期79-83,共5页
By applying nanotechnology, a new type of silver/graphite (AgC) electricalcontact was fabricated and characterized. The AgC coating powders were obtained through high-energyball milling and reducer liquid spraying-coa... By applying nanotechnology, a new type of silver/graphite (AgC) electricalcontact was fabricated and characterized. The AgC coating powders were obtained through high-energyball milling and reducer liquid spraying-coating method. The as-prepared powders were examined bytransmission electron microscope (TEM), scanning electron microscope (SEM), and X-ray diffraction(XRD). The results show that the thickness of graphite flakes milled for 10 h is about 50-60 nm andthe AgC coating powders exhibit flocculent structure with quite fine and homogeneous internalmicropores. XRD implies that the average crystalline size of silver in coating powders is about 50nm. The mechanical and physical properties of this newly developed AgC contact made from theabove-mentioned nanocrystalline powders by traditional powder metallurgy technique were measured.Compared with its counterparts made from other techniques, the properties of this new AgC contacthave been optimized. High surface energy and high-energy interfaces of the nanocrystalline AgCcoating powders provide powerful driving force for sintering densification. Moreover, the flocculentstructure of the powders is also an important factor to acquire fine density ratio. 展开更多
关键词 contact material AgC-N (newly developed) NANOTECHNOLOGY high-energy ballmilling reducer liquid spraying-coating method optimization
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Updates in version 2019 of CSCO guidelines for colorectal cancer from version 2018 被引量:7
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作者 Ying Yuan Xicheng Wang +10 位作者 Gong Chen Yi Wang Weiqi Sheng Xinxiang Li Aiping Zhou Zhen Zhang Guichao Li Sanjun Cai Ruihua Xu Jin Li Suzhan Zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第3期423-425,共3页
According to the latest data from cancer registration center, there are estimated to be 3,929,000 individuals newly diagnosed with cancer and 2,338,000 deaths from this disease in China in 2015 (1). Among them, colore... According to the latest data from cancer registration center, there are estimated to be 3,929,000 individuals newly diagnosed with cancer and 2,338,000 deaths from this disease in China in 2015 (1). Among them, colorectal cancer (CRC) with 388,000 newly diagnosed cases and 187,000 deaths, stands the third place in incidence and the fifth place in mortality. The Chinese Society of Clinical Oncology (CSCO) has organized an expert committee to write and publish the Guideline for Colorectal Cancer in 2017. And its English version has already been published in March 2019 (2). According to the latest progress, the expert committee updated the guideline to the 2019 version in this April, and the summary of the main updates are as following. 展开更多
关键词 According to the latest individuals newly are as following
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Recent progress in carbon-based electrochemical catalysts:From structure design to potential applications 被引量:2
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作者 Jixin Yan Fenghui Ye +4 位作者 Quanbin Dai Xinyue Ma Zhihai Fang Liming Dai Chuangang Hu 《Nano Research Energy》 2023年第2期3-25,共23页
Advances in research and development of carbon-based metal-free electrocatalysts(C-MFECs)have provided potential alternatives to precious metal catalysts for various reactions important to renewable energy and environ... Advances in research and development of carbon-based metal-free electrocatalysts(C-MFECs)have provided potential alternatives to precious metal catalysts for various reactions important to renewable energy and environmental remediation.This timely but critical review provides an overview of recent breakthroughs(within the past 5 years or so)on C-MFECs in all aspects,including the design and regulation of intrinsic catalytic active sites,design and synthesis of carbon composite and hybrid carbon catalysts,mechanism understanding,and potential applications in clean energy storage and energy/chemical conversion.Current challenges and future opportunities in the field of metal-free carbon electrocatalysis are also discussed to provide forward-looking opportunities for their potential applications in various catalytic processes of practical significance. 展开更多
关键词 carbon-based metal-free electrocatalysts intrinsic regulation structural design optimized composition newly developed application
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Chrysosplenium fallax Koldaeva(Chrysosplenium),a newly recorded species from China
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作者 Xiang Niyan Chen Xitang +2 位作者 Yang Tiange Liu Xihong Liu Hong 《植物科学学报》 CAS CSCD 北大核心 2024年第4期423-430,共8页
Chrysosplenium fallax Koldaeva,recently discovered and collected in Yanji,Jilin Province,repre-sents a newly recorded species of Saxifragaceae in China.This species,native to the Russian Far East,was first described a... Chrysosplenium fallax Koldaeva,recently discovered and collected in Yanji,Jilin Province,repre-sents a newly recorded species of Saxifragaceae in China.This species,native to the Russian Far East,was first described as a new species in 2021.Based on precise field investigations and specimen examination,we provide a comprehensive description of C.fallax and its seed micromorphology.Phylogenetic analysis based on chloroplast genomes of 45 Chrysosplenium species confirmed the systematic position of C.fallax in Chrysosplenium.Voucher specimens were deposited in the Herbarium of South-Central Minzu University(HSN). 展开更多
关键词 Chrysosplenium fallax Chrysosplenium newly record PHYLOGENY China
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项目区尺度下新增耕地可持续利用综合评价——基于中国广东的案例分析
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作者 郭畅 金晓斌 +3 位作者 杨绪红 徐伟义 孙瑞 周寅康 《Journal of Geographical Sciences》 SCIE CSCD 2024年第4期745-762,共18页
Cultivated land plays a pivotal role in ensuring national food security,particularly in populous nations like China,where substantial investments are made to develop cultivated land as a counterbalance to construction... Cultivated land plays a pivotal role in ensuring national food security,particularly in populous nations like China,where substantial investments are made to develop cultivated land as a counterbalance to construction-occupied areas.Consequently,long-term,effective monitoring of the utilization of newly cultivated land becomes imperative.This study introduces a comprehensive monitoring framework,designed for refined scales,that leverages remote sensing data.The framework focuses on the sustainable utilization of newly cultivated land,emphasizing utilization sustainability,productivity stability,and landscape integration.Its effectiveness was validated through a case study in Guangdong province,China.The results revealed satisfactory utilization sustainability and improved productivity stability of newly cultivated land in Guangdong,though landscape integration showed sub-optimal results.Furthermore,the comprehensive evaluation categorized the newly cultivated land into three levels and eight types.The study recommends enhancing the site selection process for newly cultivated land and improving the long-term monitoring,as well as incentive and constraint mechanisms,for their utilization.This study can provide a scientific reference to bolster the implementation of cultivated land protection policies,thereby contributing significantly to high-quality economic and social development. 展开更多
关键词 land consolidation newly cultivated land utilization sustainability productivity stability landscape integration GUANGDONG
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Epidemiology of Leprosy in China,2021:An Update
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作者 Ying Shi Pei-Wen Sun +3 位作者 Le Wang Hong-Sheng Wang Mei-Wen Yu Heng Gu 《International Journal of Dermatology and Venereology》 CSCD 2024年第1期35-39,共5页
Objective:Leprosy is an infectious diseases that remains a concerning public health issue.The infection of Mycobacterium leprae still exists at the county level in hard-to-access areas in southwest China.An accurate a... Objective:Leprosy is an infectious diseases that remains a concerning public health issue.The infection of Mycobacterium leprae still exists at the county level in hard-to-access areas in southwest China.An accurate analysis of the prevalence of leprosy in various regions is necessary for the formulation of prevention and control strategies,so we conducted this study to describe the epidemiological characteristics of leprosy in China in 2021 and provide essential information for future national leprosy control and prevention strategies.Methods:We collected epidemiological data of leprosy from 31 provinces,autonomous regions,and municipalities of China(except for Hong Kong,Macao,and Taiwan)provided by the Leprosy Management Information System.We performed a comparative analysis of the epidemiological features of patients with leprosy including age,sex,geographical distribution,and grade of disability.Results:In total,374 newly detected leprosy cases were reported nationwide in China in 2021,giving an incidence rate of 0.27 per million population,which represented a decrease of 7.9%compared with 2020.Among the population with leprosy in 2021 that comprised 238 males(63.6%)and 136 females(36.4%),1.9%(7/374)were children younger than 15 years,92.8%(347/374)had multibacillary leprosy,and 18.2%(68/374)had grade 2 disability.More than half of the new leprosy cases(54.8%,205/374)were distributed in southwest China.There were 33 relapsed leprosy cases reported in 2021.By the end of 2021,there were 1,897 registered leprosy cases reported nationwide,giving a prevalence rate of 1.35 per million population.Conclusion:The leprosy epidemic in China shows a downward trend in terms of the prevalence and incidence rates.However,the high prevalence of leprosy in southwest China is still a matter of concern. 展开更多
关键词 EPIDEMIOLOGY LEPROSY China newly detected leprosy cases multibacillary leprosy paucibacillary leprosy incidence rate prevalence rate
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Snapshot Survey of the Presence of Perfluoroalkyl Substances in Products, Articles, and the Environment in Ecuador
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作者 Heidelore Fiedler Luis Vega-Bustillos +2 位作者 Jenny Arias-Pastrano Lander Vinicio Pérez-Aldás Jose Castro-Díaz 《Engineering》 SCIE EI CAS CSCD 2024年第6期49-61,共13页
The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production... The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the POPs listed in Annexes A,B,or C;provide information to registers;maintain inventories;and monitor the presence of POPs in the environment.In the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(PFAS)in its national implementation plan and sent selected products from its national market for PFAS analysis.The products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and pesticides.Our results showed that the three PFAS presently listed in the Stockholm Convention could be quantified in only a few samples;additional PFAS,not yet listed in the Convention also had low detection frequencies.Although the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel Convention—they would not constitute a disposal problem.Nevertheless,verification of the presence of PFAS in products on the market is expected to pose an analytical challenge for both,developed and developing countries. 展开更多
关键词 Emerging or newly listed POPs Stockholm Convention Products and articles PFAS analysis Developing countries
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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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