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Search Results: 1 - 10 of 80876 matches for " Xinqing Liu "
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Holocene climatic and environmental changes recorded in Baahar Nuur Lake core in the Ordos Plateau, Inner Mongolia of China
LanLan Guo,ZaoDong Feng,XinQing Li,LianYou Liu,LiXia Wang
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0132-1
Abstract: A 5.3 m lake core was drilled in Baahar Nuur Lake in the Ordos Plateau, and measurements of mean grain size, organic δ 13C (δ 13Corg), organic carbon content (TOC), C/N, carbonate content, carbonate δ 13C (δ 13Ccar) and δ 18O (δ 18Ocar) were conducted for retrieving the Holocene chronosequence of climatic changes based on 15 AMS 14C dates. The record documented four major stages of climate change in the Ordos Plateau: (IV) a cold and dry condition before ~7.65 14C ka BP; (III) a warm and humid stage between ~7.65 and ~5.40 ka BP; (II) a generally drier and cooler climate since ~5.40 ka BP with two humid events occurring from ~4.70 to ~4.60 ka BP and from ~4.20 to ~3.70 ka BP, and (I) a dry climate characterized by complete desiccation of the lake after 3.70 ka BP. Stage III can be further divided into three sub-stages: (IIIa) a warm and humid episode from ~7.65 to ~6.70 ka BP, (IIIb) a warm and relatively dry episode from ~6.70 to ~6.20 ka BP, and (IIIc) the magthermal and maghumid episode of the Holocene from ~6.20 to ~5.40 ka BP.
Scattering Center Modeling Using Adaptive Segmental Compressive Sampling
Scattering Center Modeling Using Adaptive Segmental Compressive Sampling

Qifeng Li,Kunyi Guo,Jiaxin Wang,Xinqing Sheng,Tianshu Liu
- , 2017, DOI: 10.15918/j.jbit1004-0579.201726.0408
Abstract: In order to deal with aliasing distortions of Doppler frequencies shown in time-frequency representation (TFR) with aspect undersampling, an approach using adaptive segmental compressive sampling according to the aspect dependencies of the scattering centers is proposed. The random noise problem induced by compressive sampling is solved by employing a series of signal processing techniques of filtering, image transformation and Hough Transform. Three examples are presented to verify the effectiveness of this approach. The comparisons between the built models and the precise scattered fields computed by a well-validated full-wave numerical method are investigated, and the results show good agreements between each other.
In order to deal with aliasing distortions of Doppler frequencies shown in time-frequency representation (TFR) with aspect undersampling, an approach using adaptive segmental compressive sampling according to the aspect dependencies of the scattering centers is proposed. The random noise problem induced by compressive sampling is solved by employing a series of signal processing techniques of filtering, image transformation and Hough Transform. Three examples are presented to verify the effectiveness of this approach. The comparisons between the built models and the precise scattered fields computed by a well-validated full-wave numerical method are investigated, and the results show good agreements between each other.
Translational medicine as a permanent glue and force of clinical medicine and public health: perspectives (1) from 2012 Sino-American symposium on clinical and translational medicine
Jiebai Zhou, Duojiao Wu, Xinqing Liu, Shuoqi Yuan, Xiaoqiu Yang, Xiangdong Wang
Clinical and Translational Medicine , 2012, DOI: 10.1186/2001-1326-1-21
Abstract: Clinical and translational medicine (CTM) has been highly emphasized since Dr. Elias Zerhouni, the former director of the National Institutes of Health, proposed “The NIH Roadmap” in 2003 [1]. CTM is an emerging area comprising multidisciplinary research from basic sciences to medical applications and entails a close collaboration between clinicians and basic scientists across institutes. It is further defined as a two-way road: bench-to-bedside and bedside-to-bench [2], to translate discoveries from the bench into clinical application and/or the translation of clinical findings into the understanding of molecular mechanisms. CTM was emphasized to play a unique and critical role in optimizing new biotechnologies, improving clinical application of new therapeutic concepts, and ultimately improving the quality of life for patients [3]. The emergence of translational science highlights the unifying framework that bridges the continuum of knowledge creation and deployment, converting fundamental discoveries to human application, advancing the information into clinical practice, disseminating best clinical practices into communities and, ultimately, modifying the behavior of populations to improve global health [4].It is of great significance to promote CTM among clinicians, basic researchers, biotechnologists, politicians, ethicists, sociologists, or investors and coordinate these efforts among different countries [5]. CTM as an inter-disciplinary science is developing widely and become a global priority. The 2012 Sino-American Symposium on Clinical and Translational Medicine (SAS-CTM) as one of milestone conferences on CTM was organized by Chinese Academy of Engineering, Chinese Academy of Medical Sciences, The U.S. National Institutes of Health Clinical Center, and GlobalMD Organization. The SAS-CTM was established as a bridge between China and the U.S. to exchange ideas on clinical and translational research, built up the highest level and most influential collaborat
Nitrogen and phosphorus balance analysis of cultivated land in Jiangsu plain, China
Xinqing Zou,Pierre Gerber,Haiyu Li,Qingsong Liu,Qian Wang,Jingfen Shen,Binwen Shi
Chinese Science Bulletin , 2001, DOI: 10.1007/BF03187249
Abstract: Jiangsu plain is located along the downstream of the Yangtze River, the north part of which is also the coast area of the Yellow Sea. The specific location makes the local environmental issues regionally important. This paper studied arable land area, plantation structure, livestock sector data, which shows that livestock sector contributes a big amount of nitrogen and phosphorus, in terms of the demand from the agriculture use in Jiangsu plain. But actually, there is still much mineral fertiliser used in agriculture, which causes the N and P produced from livestock sector being an important source of pollution to the environment. The paper suggests to tighten up manure management, in order to lead to a big reduction in the pollution to both soil and surface water.
Holocene climatic and environmental changes recorded in Baahar Nuur Lake in the Ordos Plateau, Southern Mongolia of china
Holocene climatic and environmental changes recorded in Baahar Nuur Lake core in the Ordos Plateau, Inner Mongolia of China

Guo Lanlan,
GUO
,LanLan,FENG,ZaoDong,LI,XinQing,LIU,LianYou,WANG,LiXia

科学通报(英文版) , 2007,
Abstract: A 5.3 m lake core was drilled in Baahar Nuur Lake in the Ordos Plateau, and measurements of mean grain size, organic δ 13C (δ 13Corg), organic carbon content (TOC), C/N, carbonate content, carbonate δ 13C (δ 13Ccar) and δ 18O (δ 18Ocar) were conducted for retrieving the Holocene chronosequence of climatic changes based on 15 AMS 14C dates. The record documented four major stages of climate change in the Ordos Plateau: (IV) a cold and dry condition before ~7.65 14C ka BP; (III) a warm and humid stage between ~7.65 and ~5.40 ka BP; (II) a generally drier and cooler climate since ~5.40 ka BP with two humid events occurring from ~4.70 to ~4.60 ka BP and from ~4.20 to ~3.70 ka BP, and (I) a dry climate characterized by complete desiccation of the lake after 3.70 ka BP. Stage III can be further divided into three sub-stages: (IIIa) a warm and humid episode from ~7.65 to ~6.70 ka BP, (IIIb) a warm and relatively dry episode from ~6.70 to ~6.20 ka BP, and (IIIc) the magthermal and maghumid episode of the Holocene from ~6.20 to ~5.40 ka BP. Supported by the National Natural Science Foundation of China (Grant Nos. 40025105, 40331102, 40421101 and 40671184), US National Science Foundation (Grant No. NSF-ESH04-02509), Ministry of Science and Technology of China (Grant No. G2000048701) and National Geographic Ministry of Society (Grant No. NGS-6938-00)
Five-year Prognosis after Mild to Moderate Ischemic Stroke by Stroke Subtype: A Multi-Clinic Registry Study
Yumei Lv, Xianghua Fang, Karam Asmaro, Hongjun Liu, Xinqing Zhang, Hongmei Zhang, Xiaoming Qin, Xunming Ji
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0075019
Abstract: Background and Purpose Mild to moderate ischemic stroke is a common presentation in the outpatient setting. Among the various subtypes of stroke, lacunar infarction (LI) is generally very common. Currently, little is known about the long-term prognosis and factors associated with the prognosis between LI and non-LI. This study aims to compare the risk of death and acute cardiovascular events between patients with LI and non-LI, and identify potential risk factors associated with these outcomes. Methods A total of 710 first-ever ischemic stroke patients (LI: 474, non-LI: 263) from 18 clinics were recruited consecutively from 2003 to 2004. They were prospectively followed-up until the end of 2008. Hazard ratios and 95% confidence intervals were calculated using multivariable Cox proportional hazards regression. Results After a 5-year follow up, 54 deaths and 96 acute cardiovascular events occurred. Recurrent stroke was the most common cause of death (19 cases, 35.18%) and new acute cardiovascular events (75 cases, 78.13%). There were no significant differences between patients with LI and non-LI in their risks of death, new cardiovascular events, and recurrent stroke after adjusting for age, sex, hypertension, diabetes, cardiac diseases, body mass index, dyslipidemia, smoking, alcohol consumption, ADL dependence, and depressive symptoms. Among the modifiable risk factors, diabetes, hypertension, ADL dependency, and symptoms of depression were independent predictors of poor outcomes in patients with LI. In non-LI patients, however, no modifiable risk factors were detected for poor outcomes. Conclusion Long-term outcomes did not differ significantly between LI and non-LI patients. Detecting and managing vascular risk factors and depression as well as functional rehabilitation may improve the prognoses of LI patients.
Aberrant Functional Organization within and between Resting-State Networks in AD
Jinyu Song, Wen Qin, Yong Liu, Yunyun Duan, Jieqiong Liu, Xiaoxi He, Kuncheng Li, Xinqing Zhang, Tianzi Jiang, Chunshui Yu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063727
Abstract: Altered functional characteristics have been reported in amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD); nonetheless, comprehensive analyses of the resting-state networks (RSNs) are rare. This study combined multiple imaging modalities to investigate the functional and structural changes within each RSN and between RSNs in aMCI/AD patients. Eight RSNs were identified from functional MRI data from 35 AD, 18 aMCI and 21 normal control subjects using independent component analysis. We compared functional connectivity (FC) within each RSN and found decreased FC in the several cognitive-related RSNs in AD, including the bilateral precuneus of the precuneus network, the posterior cingulate cortex and left precuneus of the posterior default mode network (DMN), and the left superior parietal lobule of the left frontoparietal network (LFP). We further compared the grey matter volumes and amplitudes of low-frequency fluctuations of these regions and found decreases in these measures in AD. Importantly, we found decreased inter-network connectivity between the visual network and the LFP and between the anterior and posterior DMNs in AD. All indices in aMCI patients were numerically between those of controls and AD patients. These results suggest that the brain networks supporting complex cognitive processes are specifically and progressively impaired over the course of AD, and the FC impairments are present not only within networks but also between networks.
The Distributional Characteristics of Heavy Metal in Jiangsu Province Shoal Sea
Yu Wenjin,Zou Xinqing
Journal of Environmental and Public Health , 2013, DOI: 10.1155/2013/142065
Abstract: After the analysis of surface samples and core samples collected in Xinyanggang tidal land, the contents of Pb, Cu, Zn, and Cr were obtained and analyzed in this paper. The heavy metal accumulation rule and pollution status were studied by Index of geo-accumulation, latent ecological risk index method, and elements accumulation index method. The research suggests that (1) the contents of heavy metal Pb, Cu, Zn, and Cr in Xinyanggang tidal land have the same change trend, and such trend remains unchanged after the data were normalized, while the fluctuation range becomes smaller. (2) After analyzing the heavy metal content in the surface samples, it was revealed that the contents of heavy metals are getting lower from high tidal zone to low tidal zone, but the ranges of the change were different. Cu, Ni, and Zn emerge obvious decline from supratidal zone to subtidal zone, while the changes of Cr and Pb are not obvious. (3) Pb and Cr contents in Xinyanggang tidal land present accumulative character, as Pb in Xinyanggang is 3 times as much as the local background value, whose EF reaches 3.774. (4) RI value in Xinyanggang is 23.552, which indicates that though Xinyanggang tidal land has some heavy metal pollution and accumulation, there are no ecosystem risks, and the whole Xinyanggang core area environment quality is relatively good. 1. Introduction As a special coastal wetland, tidal wetland is a complicated multiple-functional ecosystem with unique ecovalue and resource potential. In tidal zone, heavy metals cannot be purified through water self-purification; they normally sink into sediments after deposition and accumulation in tidal land through complicated physical, chemical, and biological process. Xu carried out researches on the spatial distributions of heavy metals and their dynamic accumulating characteristics in Shanghai coastal tidal land [1] which indicate that, in large scale, the spatial distribution pattern of the heavy metal Cu, Zn, Cr, and Pb in tidal flat sediments was not directly affected by coastal pollution discharges, rather they were closely related to sediment dynamics; while in small scale, the content of heavy metals in the tidal land near the drain was closely related to the drain. Bi Ch [2] studied different variation patterns of the existing form of heavy metal Cu, Zn, Cr, and Pb in different seasons, different locations in tidal land near the Bailonggang drain, and the shape, content, and distribution in the root sediments, finding that the contents of heavy metals in the tidal land near the Bailonggang drain were all
动态增强MRI半定量信号强度-时间曲线及全定量灌注参数在子宫肿瘤中的应用
Signal intensity-time curve and quantitative dynamic contrast-enhanced magnetic resonance imaging in differentiating neoplasms of uterus

郭永梅,江新青,刘国顺,黄云海,徐向东
GUO Yongmei
, JIANG Xinqing, LIU Guoshun, HUANG Yunhai, XU Xiangdong

- , 2015, DOI: 10.11817/j.issn.1672-7347.2015.12.012
Abstract: 目的:探讨3.0T动态增强MRI半定量信号强度-时间(signal intensity-time,SI-Time)曲线及全定量灌注参数在子宫病变中的应用价值。方法:回顾性分析经病理证实为子宫恶性肿瘤20例,良性肿瘤或肿瘤样病变22例。均行3.0T动态增强MRI扫描,并使用Siemens Tissue 4D软件进行图像后处理,勾画感兴趣区并绘制SI-Time曲线。进一步测得感兴趣区的容积定量灌注参数值:容量转移常数(Ktrans)、速率常数(Kep)、血管外细胞外间隙容积比(Ve)。对良、恶性病变组的SI-Time曲线类型进行统计学分析,对良、恶性病变组的定量灌注参数值进行单因素方差分析,多个样本均数的两两比较。结果:20例恶性肿瘤中宫颈癌12例,内膜癌8例;22例良性病变中13例为平滑肌瘤,3例为子宫内膜息肉,3例内膜增生,3例为子宫腺肌症。良性组以I型曲线(59.1%)为主;恶性组以II型曲线(65.0%)为主。不同类型的SI-Time曲线在良恶性病变之间差异具有统计学意义(P=0.011)。若以I型曲线作为诊断子宫良性病变的标准,II和III型曲线作为诊断子宫恶性病变的标准,则诊断灵敏度为90%,特异性为59.1%,阳性预测值为66.7%,阴性预测值为86.7%。恶性病变组Ve值比良性病变组[(0.477±0.143) vs (0.589±0.176),P=0.004]和对照组[(0.477±0.143) vs (0.614±0.146),P=0.004]均低;恶性病变组Ktrans值比对照组低[(0.178±0.067) min?1 vs (0.263±0.111) min?1,P=0.003];良性病变组Ktrans比对照组低[(0.182±0.096) min?1 vs (0.263±0.111) min?1,P=0.011]。结论:动态增强MRI半定量SI-Time曲线及全定量灌注参数值在子宫良恶性病变鉴别诊断中具有积极意义,可作为常规MRI形态学诊断的有效补充手段
中国钨矿成矿地质特征与资源潜力分析
Tungsten metallogenic geological features and mineral resources potential analyses in China.

夏庆霖,汪新庆,刘壮壮,李童斐,冯磊
XIA Qinglin
,WANG Xinqing,LIU Zhuangzhuang,LI Tongfei,FENG Lei

- , 2018, DOI: 10.13745/j.esf.2018.03.004
Abstract: 钨矿是中国传统优势矿种,前人在钨矿成矿理论方面积累了非常丰富的研究成果。然而,随着近年来在江西、云南和新疆等地取得的多项钨矿重大找矿突破,对原有的钨成矿带地质认识提出了挑战,急需进一步分析和总结其地质特征、成矿规律和资源潜力,为今后地质找矿工作提供理论指导。文中采用矿床模型综合地质信息预测方法,在各省区钨矿资源潜力预测成果的基础上,以MapGIS为平台,进行数据库汇总与综合分析研究。首先,基于全国1 538处钨矿产地数据的统计分析,初步总结了中国钨矿时空分布特征,以及岩浆岩、构造和地层等控矿因素。其次,根据钨矿床及预测区的空间分布和大地构造单元,划分了56个钨矿成矿区带。再次,将钨矿的预测类型划分为石英脉型、夕卡岩型、斑岩型、云英岩型、陆相火山岩型、沉积变质型、层控夕卡岩型和砂矿型,并建立了主要钨矿类型的预测模型。最后,在全国范围累计圈定的1 357个最小预测,累计预测资源量(WO3)2 973×104 t。根据钨矿区域成矿特征,将最小预测区归并为461个二级预测区,并进一步合并为118个钨矿三级预测区,其中,找矿潜力大的河南卢氏—栾川、新疆白干湖、湖南香花岭—瑶岗仙、甘肃野马滩—干巴河脑、江西坪背山—八仙脑和大湖塘等6个三级预测区可优先部署钨矿勘查工作。
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