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Impact of grazing on germination trait selection in an alpine grassland on the Tibet Plateau

Journal of Plant Ecology 2022年第4期15卷 818-828页

作者： Yang Liu Kun Liu Zhilong Zhang Shiting Zhang Carol C.Baskin Jerry m.Baskin Ting Liang Haiyan Bu Shuxia Li Tingting Zhang Xianliang Cui sa Xiao State Key Laboratory of Grassland and Agro-ecosystems School of Life SciencesLanzhou UniversityLanzhou 730020China department of Chemistry and Life Science Gansu Normal College for NationalitiesHezuo 74700China department of Biology University of KentuckyLexingtonKY 40506USA department of Plant and Soil Sciences University of KentuckyLexingtonKY 40506USA

Previous studies indicated that grazing can cause significant changes in abiotic and biotic environment in ***,how these changes impact germination trait selection in grassland has not been well ***,we aimed to explore whether grazing can significantly change germination trait diversity and composition of grasslands *** measured the germination traits of species in the laboratory,and compared their performance in grazed and nongrazed ***,we compared the community-weighted means of germination traits and functional diversity of grazed and nongrazed grasslands based on these germination traits to know whether grazed and nongrazed grasslands differed in their germination trait *** the species level,we found that the changes of abundance in grazed and nongrazed grasslands were not related to species’germination ***,at the community level,compared with nongrazed grasslands,species in the grazed grasslands generally exhibited a higher seed germination ***,seed germination response in grazed grasslands was more positively related to alternating temperature than in nongrazed grasslands,and breadth of the germination temperature niche was narrower in grazed than in nongrazed *** with nongrazed grasslands,seed germination trait diversity was increased and germination trait evenness decreased in grazed *** can change microhabitat conditions,thereby changing germination trait selection by environmental filtering,resulting in a significant difference in germinate trait composition at the community level.

关键词： alpine grassland biodiversity germination trait selection grazing Tibet Plateau

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Petrogenesis of the Late Cretaceous Tholeiitic Volcanism and Oceanic Island Arc Affinity of the Chagai Arc, Western Pakistan

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1248-1263页

作者： Rehanul Haq SIddIQUI m. Qasim JAN mohammad Asif KHAN m. Ishaq KAKAR John d. FOdEN Baluchistan University of Information Technology Engineering and Management Sciences Quetta Pakistan National Centre of Excellence in Geology University of Peshawar Peshawar & COMSTECH Islamabad Pakistan Karakoram International University Gilgit Pakistan Centre of Excellence in mineralogy University of Baluchistan Quetta Pakistan department of Earth Sciences University of Adelaide SA 5005 Australia

The Late Cretaceous Chagai arc outcrops in western Pakistan, southern Afghanistan and eastern Iran. It is in the Tethyan convergence zone, formed by northward subduction of the Arabian oceanic plate beneath the Afghan block. The oldest unit of the Chagai arc is the Late Cretaceous Sinjrani Volcanic Group. This is composed of porphyritic lava flows and volcaniclastic rocks, and subordinate shale, sandstone, limestone and chert. The flows are fractionated low-K tholeiitic basalts, basaltic- andesites, and andesites. Relative enrichment in their LILE and depletion in HFSE, and negative Nb and Ta and positive K, Ba and Sr anomalies point to a subduction-related origin. Compared to mORB, the least fractionated Chagai basalts have low Na2O, Fe2O3^T, CaO, Ti, Zr, Y and ^87Sr/^86Sr. Rather than an Andean setting, these results suggest derivation from a highly depleted mantle in an intraoceanic arc formed by Late Cretaceous convergence in the Ceno-Tethys. The segmented subduction zone formed between Gondwana and a collage of small continental blocks （Iran, Afghan, Karakoram, Lhasa and Burma） was accompanied by a chain of oceanic island arcs and suprasubduction ophiolites including Semail, Zagros, Chagai-Raskoh, Kandahar, muslim Bagh, Waziristan and Kohistan-Ladakh, Nidar, Nagaland and manipur. These complexes accreted to the southern margin of Eurasia in the Late Cretaceous.

关键词： Chagai arc tholeiitic volcanics Late Cretaceous western Pakistan

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3d uniform nitrogen-doped carbon skeleton for ultra-stable sodium metal anode

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Nano Research 2020年第8期13卷 2136-2142页

作者： Ben Liu danni Lei Jin Wang Qingfei Zhang Yinggan Zhang Wei He Hongfei Zheng Baisheng sa Qingshui Xie dong-Liang Peng Baihua Qu Pen-Tung sah Institute of micro-Nano Science and Technology Fujian Key Laboratory of Materials GenomeCollege of MaterialsXiamen UniversityXiamen361005China State Key Laboratory of Optoelectronic materials and Technologies School of Materials Science and EngineeringSun Yat-Sen(Zhongshan)UniversityGuangzhou510275China multiscale Computational materials Facility College of Materials Science and EngineeringFuzhou UniversityFuzhou350100China

Sodium metal batteries are arousing extensive interest owing to their high energy density,low cost and wide ***,the practical development of sodium metal batteries is inherently plagued by the severe volume expansion and the dendrite growth of sodium metal anode during long cycles under high current ***,a simple electrospinning method is applied to construct the uniformly nitrogen-doped porous carbon fiber skeleton and used as three-dimensional(3d)current collector for sodium metal anode,which has high specific surface area(1,098 m^2/g)and strong binding to sodium *** a result,nitrogen-doped carbon fiber current collector shows a low sodium deposition overpotential and a highly stable cyclability for 3,500 h with a high coulombic effciency of 99.9%at 2 mA/cm^2 and 2 mAh/cm^***,the full cells using carbon coated sodium vanadium phosphate as cathode and sodium pre-plated nitrogen-doped carbon fiber skeleton as hybrid anode can stably cycle for 300 *** results illustrate an effective strategy to construct a 3d uniformly nitrogen-doped carbon skeleton based sodium metal hybrid anode without the formation of dendrites,which provide a prospect for further development and research of high performance sodium metal batteries.

关键词： sodium metal anode porous carbon skeleton nitrogen-doping sodium affinity ultra-stable cyclability

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基于随机森林的川崎病诊断关键实验室指标预测研究

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检验医学与临床 2024年第19期21卷 2887-2891,2897页

作者：王爱琼萨日娜张巧丽柴利娜李爱月内蒙古自治区鄂尔多斯市中心医院儿科内蒙古鄂尔多斯017000 内蒙古迪安丰信医疗科技有限责任公司内蒙古呼和浩特010000

目的通过随机森林算法构建诊断模型,分析不完全川崎病区别于完全川崎病的关键实验室指标,以提高不完全川崎病的诊断率及降低其误诊率。方法选取2018年1月至2023年6月就诊于鄂尔多斯市中心医院儿科确诊为完全川崎病或不完全川崎病的患儿... 详细信息

目的通过随机森林算法构建诊断模型,分析不完全川崎病区别于完全川崎病的关键实验室指标,以提高不完全川崎病的诊断率及降低其误诊率。方法选取2018年1月至2023年6月就诊于鄂尔多斯市中心医院儿科确诊为完全川崎病或不完全川崎病的患儿145例,其中不完全川崎病34例(不完全组),完全川崎病111例(完全组)。比较两组红细胞计数、血红蛋白、红细胞沉降率、血钠、白细胞计数、血小板计数、平均血小板体积、中性粒细胞计数、中性粒细胞百分比、淋巴细胞计数、淋巴细胞百分比、C反应蛋白、丙氨酸转氨酶、总蛋白、清蛋白、总胆红素、天冬氨酸转氨酶、降钙素原(PCT)、肌酸激酶、肌酸激酶m多肽(CK-m)、N末端B型钠尿肽前体(NT-proBNP)、凝血酶原时间、凝血酶时间、d-二聚体、尿白细胞计数的差异,利用随机森林算法构建诊断模型,分析不完全川崎病区别于完全川崎病的实验室指标。结果模型结果显示,贡献度前5位的实验室指标依次为血小板计数(0.381)、尿白细胞计数(0.372)、淋巴细胞百分比(0.260)、凝血酶时间(0.255)及中性粒细胞百分比(0.163),在区分川崎病类型方面具有重要的指示意义。构建的诊断模型ROC曲线下面积为0.864,灵敏度为1.00,特异度为0.74。结论通过随机森林算法得出,血小板计数、尿白细胞计数、淋巴细胞百分比、凝血酶时间以及中性粒细胞百分比可作为诊断不完全川崎病的关键实验室指标,这为患儿的诊断与及时治疗提供理论依据。

关键词：随机森林不完全川崎病实验室指标早期诊断完全川崎病

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Polycaprolactone (PCL) Chains Grafting on the Surface of Cellulose Nanocrystals (CNCs) during <i>In Situ</i>Polymerization of <i>ε</i>-Caprolactone at Room Temperature

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materials Sciences and Applications 2020年第11期11卷 744-756页

作者： Jérémy Astruc Patrice Cousin Gaétan Laroche mathieu Robert saïd Elkoun Center of Innovative Technology and Eco-design (CITE) University of Sherbrooke Granby QC Canada Laboratoire d’Ingénierie de Surface Département de Génie des Mines de la Métallurgie et des Matériaux Centre de recherche sur les Matériaux avancés Pavillon Adrien-Pouliot University of Laval Québec QC Canada Centre de Recherche du CHU de Québec Hopital Saint-Francois d’Assise Québec QC Canada

This work aimed at investigating the feasibility of surface modification of cellulose nanocrystals (CNCs) using in situ ring opening polymerization of ε-caprolactone (ε-CL) at room temperature. Residues of flax and ... 详细信息

This work aimed at investigating the feasibility of surface modification of cellulose nanocrystals (CNCs) using m>in situm> ring opening polymerization of m>εm>-caprolactone (m>εm>-CL) at room temperature. Residues of flax and milkweed (m>Asclepias syriacam>) stem fibers were used as a source of cellulose to obtain and isolate CNCs. The cationic ring opening polymerization (CROP) of the monomer m>εm>-CL was used to covalently graft polycaprolactone (PCL) chains at the CNCs surface. Silver hexafluoroantimonate (AgSbF6) was used in combination with the extracted CNCs to initiate, at room temperature, the polymerization and the grafting reactions with no other stimulus. Fourier-Transform InfraRed (FTIR), X-ray Photoelectron Spectrometry (XPS), UV/visible absorption and Gel Permeation Chromatography (GPC) analyses evidenced the presence of PCL chains covalently grafted at CNCs surface, the formation of Ag(0) particles as well as low or moderate molecular weight free PCL chains.

关键词： Cellulose Nanocrystals (CNCs) Simultaneous Polymerization and Surface Grafting ε-Caprolactone Cationic Ring Opening Polymerization Room Temperature Silver Hexafluoroantimonate

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Zinc-oxide/PdmS-clad tapered fiber saturable absorber for passively mode-locked erbium-doped fiber laser

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Chinese Physics B 2021年第5期30卷 384-389页

作者： F d muhammad S A S Husin E K Ng K Y Lau C A C Abdullah m A mahdi department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Wireless and Photonics Networks Research Centre Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia department of Electronics and Nanoengineering Tietotie 3Aalto University02150 EspooFinland

We propose and demonstrate a passively mode-locked erbium-doped fiber laser(EdFL)based on zinc-oxide/polydimethylsiloxane(ZnO/PdmS)saturable absorber(sa)that evanescently interacts with the light on a tapered *** ZnO/PdmS composite is coated on the whole surface of the tapered fiber to guarantee the maximum efficiency of the sa device,with a measured insertion loss of 0.87 dB and a modulation depth of 6.4%.The proposed laser can generate soliton mode-locking operation at a threshold power of 33.07 *** generated output pulse yields a repetition rate and pulse width of 9.77 mHz and 1.03 ps,*** results indicate that the proposed ZnO/PdmS-clad tapered fiber could be useful as an efficient,compatible,and low-cost sa device for ultrafast laser applications.

关键词： zinc-oxide saturable absorber tapered fiber mode-locked fiber laser

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铈基镧系氧化物的制备与晶体结构变化

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核化学与放射化学 2017年第2期39卷 145-150页

作者：孟凡石陈丹莹林有奇韩东梅康明亮 sad Obbade 中山大学中法核工程与技术学院广东珠海519082 法国格勒诺布尔综合理工学院法国格勒诺布尔31800

通过制备和表征镧系元素的氧化物来模拟研究次锕系元素的混合氧化物固溶体的晶体结构。采用草酸盐共沉淀法和程序煅烧,得到了阳离子分布均匀的以CeO_2为本底的混合氧化物Ce_(1-x)Ln_xO_(2-x/2)(其中x∈[0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0... 详细信息

通过制备和表征镧系元素的氧化物来模拟研究次锕系元素的混合氧化物固溶体的晶体结构。采用草酸盐共沉淀法和程序煅烧,得到了阳离子分布均匀的以CeO_2为本底的混合氧化物Ce_(1-x)Ln_xO_(2-x/2)(其中x∈[0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1];Ln=Nd、Sm)。利用红外光谱、拉曼光谱、热重分析和X射线衍射,表征了草酸盐前驱体(Ce_(1-x)Ln_x)_2(C_2O_4)_3·10H_2O的结构和特殊官能团,并使用X射线衍射法研究了Ce_(1-x)Ln_xO_(2-x/2)系列混合氧化物的晶体结构。结果表明,当固体氧化物中镧系元素含量较低时(对于Nd,x≤0.4;对于Sm,x≤0.3),可观察到典型的Fm-3 m萤石结构;当x较高(对于Nd,x≥0.5;对于Sm,x≥0.4)时,可观察到Ia-3立方结构。通过Rietveld方法计算晶格常数,表明其与平均阳离子半径遵从一种二次关系,这种二次关系是逐渐增长的平均阳离子半径和由于氧空位造成的O-O斥力减少综合作用的结果。

关键词：核燃料 X射线衍射 Rietveld精修固溶体铈基镧系氧化物

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Soft-tissue management and reconstruction of lower-extremity trauma

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Plastic and Aesthetic Research 2022年第1期9卷 233-242页

作者： sammy Othman said C.Azoury Kevin m.Klifto LScott Levin Stephen J.Kovach department of Plastic and Reconstructive Surgery Northwell HealthNew YorkNY 1075USA division of Plastic and Reconstructive Surgery Department of SurgeryMemorial Sloan Kettering Cancer CenterNew YorkNY 1075USA division of Plastic and Reconstructive Surgery Department of SurgeryUniversity of MissouriColumbiaMO 65211USA department of Orthopedic Surgery University of PennsylvaniaPhiladelphiaPA 19104USA division of Plastic and Reconstructive Surgery Department of SurgeryUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Soft-tissue management and subsequent salvage of the lower extremity following trauma has long presented difficult challenges to the plastic *** to the lower extremity can produce long-term sequelae consisting of psychological trauma,functional deficits,and increased costs to the healthcare *** incorrect management is important,and is compounded by the fact that few guidelines exist on appropriate treatment and patient *** study aims to describe the authors’experience at a large limb salvage center in order to further delineate management strategies.

关键词： Reconstructive surgery trauma lower extremity microsurgery soft-tissue

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Celecoxib enhances the detoxification of diethylnitrosamine in rat liver cancer

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World Journal of Gastroenterology 2009年第19期15卷 2345-2350页

作者： martha Estela salcido-Neyoy Adolfo Sierra-santoyo Olga Beltrán-Ramírez José Roberto macías-Pérez saúl Villa-Trevio department of Cell Biology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México External Section of Toxicology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México

AIm： To study the effect of celecoxib （CXB） on diethylnitrosamine activation through the regulation of cytochrome P450 in a hepatocarcinogenesis ***： Six-week-old male Sprague-dawley rats were randomly divided into five groups, a non-treated group （NT）, a diethylnitrosamine-treated group （dEN）, a dEN＋CXB-treated group （dEN＋CXB）,and CXB 8 d-treated and CXB 32 d-treated groups. The effects of celecoxib on the enzymatic activities of CYP1A1, 2A, 2B1/2, and 2E1 were assessed in hepatic microsomes 24 h after dEN *** in CYPIA1 and CYP2B1/2 protein expression were also evaluated. The rate of dEN metabolism was measured by the production of the deethylation metabolite acetaldehyde, and the denitrosation metabolite ***： dEN＋CXB administration produced a significant increase in the enzymatic activities ofCYP2B1/2 and 1A1, whereas it did not change the activities of CYP2A and 2E1, compared to that of the dEN group. CXB treatment for eight days did not produce a significant effect on enzymatic activity when compared to the NT group; however, when it was administered for prolonged times （CXB 32 d group）,the enzymatic activities were increased in a similar pattern to those in the dEN＋CXB group. The observed increase in the enzymatic activities in the dEN＋CXB group was accompanied by an increase in the CYP2B1/2 protein levels; no changes were observed in the levels of CYPIA1. In vitro, CXB increased the denitrosation of dEN, a pathway of metabolic detoxification. The addition of SKF-525A, a preferential inhibitor of CYP2B, abrogated the denitrosation of ***： These results suggest that the mechanism of action of CXB involves enhancement of the detoxification of dEN by an increasing denitrosation via CYP2B1/2.

关键词： Hepatocarcinogenesis Chemoprevention diebhylnitrosamine denitrosation Celecoxib CytochromesP450

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Relevant Frequency of multiple Infections with High- and Low-Risk HPV Genotypes among mexican Women Attending a Tertiary Care Hospital

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Open Journal of Obstetrics and Gynecology 2016年第7期6卷 424-432页

作者： saúl Flores-medina Carmen S. García-Romero diana m. Soriano-Becerril Francisco J. díaz-García Silvia Giono-Cerezo Graciela Castro-Escarpulli departamento Editorial Instituto Nacional de Perinatología Ciudad de México México CECyT No. 15 “dAE” Instituto Politécnico Nacional Ciudad de México México Programa de Biología y Biotecnología molecular Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional Ciudad de México México departamento de Infectología Instituto Nacional de Perinatología Ciudad de México México departamento de Biología Facultad de Química Universidad Nacional Autónoma de México Ciudad de México México Laboratorio de Bacteriología médica Departamento de Microbiología Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional Ciudad de México México

Aims: To assess the frequency and the main HPV genotypes circulating among a group of women attending at a third level Hospital in mexico City. methods: A cross-sectional and descriptive study was performed in a group of 143 female outpatients of the Gynecology and Obstetrics Service at the National Institute of Perinatology of mexico. Cervical swabs were taken from participants and subjected to simultaneous detection/genotyping of HPV by Linear Array Genotyping Test (Roche molecular Systems). mann-Whitney U, median and/or Square Chi tests were used to compare socio-demographical features between HPV-infected and uninfected women. Results: A total of 66 women (46.2%) had HPV infection. Overall, 112 genotypes were detected either as single infections (45.5%) or multiple genotype infections (54.5%). The cumulated frequency of multiple infections with high-/low- and high-/high-risk HPV genotypes was 63.9 %. The most frequent high-risk genotypes were HPV52 HPV58 and HPV51, whereas the most frequent low-risk genotypes were HPV6, HPV53 and HPV84. Infected women were significantly younger and have less stable partner relationships than uninfected women (p mixed infections with high- and low-risk HPV genotypes, other than those considered most prevalent worldwide, was observed. most circulating high-risk genotypes among the women of this study are not covered by commercial vaccine formulations.

关键词： Human Papillomavirus High-Risk Genotypes HPV Co-Infections Linear Array Genotyping

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