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燕山地区国家重点保护鸟类生境评估与国家级自然保护区保护空缺分析 被引量:8
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作者 谢文冬 贾嘉 +6 位作者 卜长利 马黎明 郭建刚 宋凯 李欣海 孙悦华 方昀 《动物学杂志》 CAS CSCD 北大核心 2022年第2期170-184,共15页
燕山地区地处太行山生物多样性保护优先区,紧邻人口密集的京津冀城市群,拥有很高的鸟类物种多样性。为探讨燕山地区的鸟类生境状况与保护效益,本研究以当地40种国家重点保护鸟类为指示物种,利用物种分布模型和Marxan系统保护规划模型进... 燕山地区地处太行山生物多样性保护优先区,紧邻人口密集的京津冀城市群,拥有很高的鸟类物种多样性。为探讨燕山地区的鸟类生境状况与保护效益,本研究以当地40种国家重点保护鸟类为指示物种,利用物种分布模型和Marxan系统保护规划模型进行了保护空缺分析与保护策略优化。研究发现,在燕山地区的鸟类生境中,森林的面积最大(6537 km^(2)),连贯性最强,而湿地仅有345 km^(2),占总面积之比为3.3%,且在景观格局中各斑块之间分散程度高。目前燕山地区国家级自然保护区所保护的94.6%为森林与草地生境,湿地生境面积极少。物种分布模型预测重点保护鸟类多样性高的地区偏向于湿地生境,与湖泊的距离因子在模拟过程中贡献度最大。通过Marxan模型分析获得需要优先保护的生物多样性热点区的面积为2442 km^(2),比目前保护区面积提高了6倍。热点区内生境类型更加平均,湿地在受保护区域中的生境面积占比提高至7.9%。新规划的热点区中指示物种平均受保护比例由1.2%上升至33.6%,提高了28倍。本研究显示,燕山地区的国家级自然保护区呈现较大的保护空缺,新规划的热点区可为未来燕山地区的国家公园建设和保护规划提供重要依据。 展开更多
关键词 MAXENT 燕山 MARXAN 景观破碎化 保护空缺 国家级自然保护区 国家重点保护野生鸟类
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Synergistic mechanism between SDBS and oleic acid in anionic flotation of rhodochrosite 被引量:7
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作者 Yong-jie bu Run-qing Liu +1 位作者 Wei Sun yue-hua Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第5期447-452,共6页
Pure mineral flotation experiments, zeta potential testing, and infrared spectroscopy were employed to investigate the interracial reactions of oleic acid (collector), sodium dodecyl benzene sulfonate (SDBS, synerg... Pure mineral flotation experiments, zeta potential testing, and infrared spectroscopy were employed to investigate the interracial reactions of oleic acid (collector), sodium dodecyl benzene sulfonate (SDBS, synergist), and rhodochrosite in an anionic system. The pure mineral test shows that oleic acid has a strong ability to collect products on rhodochrosite. Under neutral to moderately alkaline conditions, low temperature (e.g., 10℃) adversely affects the flotation performance of oleic acid; the addition of SDBS significantly improves the dis- persion and solubility of oleic acid, enhancing its collecting ability and flotation recovery. The zeta potential test shows that rhodochrosite interacts with oleic acid and SDBS, resulting in a more negative zeta potential and the co-adsorption of the collector and synergist at the mineral surface. Infrared spectroscopy demonstrated that when oleic acid and SDBS are used as a mixed collector, oleates along with -COO- and --COOH functional groups are formed on the mineral surface, indicating chemical adsorption on rhodochrosite. The results demonstrate that oleic acid and SDBS co-adsorb chemically on the surface ofrhodochrosite, thereby improving the flotation performance of the collector. 展开更多
关键词 RHODOCHROSITE FLOTATION sodium dodecyl benzene sulfonate oleic acid synergistic effects TEMPERATURE
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Endoscopic Ruler for varix size measurement:A multicenter pilot study
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作者 Yi-Fei huang Sheng-Juan Hu +29 位作者 Yang bu Yi-Ling Li Yan-Hong Deng Jian-Ping Hu Shao-Qi Yang Qian Shen Mark McAlindon Rui-Chun Shi Xiao-Qin Li Tie-Ying Song Hai-Long Qi Tai-Wei Jiao Meng-Yuan Liu Fang He Jun Zhu Bin Ma Xiao-Bin Yu Jian-Yang Guo yue-hua Yu Hai-Jiang Yong Wen-Tun Yao Ting Ye hua Wang Wen-Fu Dong Jian-Guo Liu Qiang Wei Jing Tian Xiao-Guo Li Xavier Dray Xiao-Long Qi 《World Journal of Gastrointestinal Endoscopy》 2023年第9期564-573,共10页
BACKGROUND We invented Endoscopic Ruler,a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension.AIM To assess the feasibility and safety of Endoscopic Ruler,and evalua... BACKGROUND We invented Endoscopic Ruler,a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension.AIM To assess the feasibility and safety of Endoscopic Ruler,and evaluate the agreement on identifying large oesophageal varices(OV)between Endoscopic Ruler and the endoscopists,as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler.METHODS We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals,all of whom got esophagogastroduodenoscopy(EGD)with Endoscopic Ruler.The primary study outcome was a successful measurement of the size of varices using Endoscopic Ruler.The secondary outcomes included adverse events,operation time,the agreement of identifying large OV between the objective measurement of Endoscopic Ruler and the empirical reading of endoscopists,together with the interobserver agreement on diagnosing large OV by Endoscopic Ruler.RESULTS From November 2020 to April 2022,a total of 120 eligible patients with cirrhosis were recruited and all of them underwent EGD examinations with Endoscopic Ruler successfully without any adverse event.The median operation time of Endoscopic Ruler was 3.00 min[interquartile range(IQR):3.00 min].The kappa value between Endoscopic Ruler and the endoscopists while detecting large OV was 0.52,demonstrating a moderate agreement.The kappa value for diagnosing large OV using Endoscopic Ruler among the six independent observers was 0.77,demonstrating a substantial agreement.CONCLUSION The data demonstrates that Endoscopic Ruler is feasible and safe for measuring the size of varices in patients with cirrhosis and portal hypertension.Endoscopic Ruler is potential to promote the clinical practice of the two-grade classification system of OV. 展开更多
关键词 Oesophageal varices CIRRHOSIS Portal hypertension ESOPHAGOGASTRODUODENOSCOPY Endoscopic ruler
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Upper bounds on vertex distinguishing chromatic index of some Halin graphs
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作者 ZHU Jun-qiao bu yue-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第3期329-334,共6页
A vertex distinguishing edge coloring of a graph G is a proper edge coloring of G such that any pair of vertices has the distinct sets of colors. The minimum number of colors required for a vertex distinguishing edge ... A vertex distinguishing edge coloring of a graph G is a proper edge coloring of G such that any pair of vertices has the distinct sets of colors. The minimum number of colors required for a vertex distinguishing edge coloring of a graph C is denoted by Xs'8(G). In this paper, we obtained upper bounds on the vertex distinguishing chromatic index of 3-regular Halin graphs and Halin graphs with △(G) ≥ 4, respectively. 展开更多
关键词 vertex distinguishing edge coloring Halin graph upper bound planar graph.
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四川某奶牛场犊牛腹泻主要病原微生物的PCR检测 被引量:1
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作者 卜娴 汤承 岳华 《动物医学进展》 北大核心 2023年第1期136-140,共5页
为了解四川省某奶牛场2月龄内犊牛腹泻的主要病原及其感染情况,采集22份犊牛腹泻粪便,PCR检测牛A群轮状病毒(BRVA)、牛冠状病毒(BCoV)、牛病毒性腹泻病毒(BVDV)、牛诺如病毒(BNoV)、纽布病毒(NeV)、牛环曲病毒(BToV)、产肠毒素大肠埃希... 为了解四川省某奶牛场2月龄内犊牛腹泻的主要病原及其感染情况,采集22份犊牛腹泻粪便,PCR检测牛A群轮状病毒(BRVA)、牛冠状病毒(BCoV)、牛病毒性腹泻病毒(BVDV)、牛诺如病毒(BNoV)、纽布病毒(NeV)、牛环曲病毒(BToV)、产肠毒素大肠埃希氏菌(ETEC)和沙门氏菌(Salmonella)共8种腹泻相关病原,并对BRVA进行基因分型。结果表明,22份粪便样本中,BRVA、BCoV、NeV和BToV的检出率分别为81.82%、31.82%、27.27%和13.64%,其中BRVA的检出率最高,存在基因型有G10、P[1]和P[11]型;且存在BRVA+BCoV、BRVA+NeV、BRVA+BToV、BRVA+BCoV+NeV混合感染,混合感染率分别为33.33%、25%、16.67%、25%,其他4种病原均未检出。可见该奶牛场犊牛腹泻主要由4种病毒感染引起,多种病毒混合感染率高,为该场犊牛腹泻的防治提供了依据。 展开更多
关键词 奶牛 腹泻 病毒 聚合酶链反应 混合感染
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