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| 1 | Reforestation Programs in Southwest China:Reported Success,Observed Failure, and the Reasons Why显示文摘Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in China’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan County, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs. | Christine Jane Trac Stevan Harrell Thomas M. Hinckley Amanda C. Henck | 2007 | Journal of Mountain Science2007，4，4： | 13 |
| 2 | An efficient sparse channel estimator combining time-domain LS and iterative shrinkage for OFDM systems with IQ-imbalances显示文摘A time-domain(TD) least square(LS) channel estimator is first proposed to estimate channel parameters of OFDM system with IQ imbalances at both transmitter and receiver.Then,an iterative shrinkage(IS) algorithm from compressed sensing is adopted to further improve the estimation performance by using the TD-LS solution as the initial value of IS in the case of sparse channel.Simulation shows that our algorithm combining TD-LS and IS performs better on bit error rate than the frequency-domain LS and matching pursuit in sparse Hilly Terrain channel when the same LS equalizer is adopted. | SHU Feng ZHAO JunHui YOU XiaoHu WANG Mao CHEN Qian STEVAN Berber | 2012 | Science China(Information Sciences)2012，55，11： | 10 |
| 3 | ML integer frequency offset estimation for OFDM systems with null subcarriers:Estimation range and pilot design显示文摘In this paper the estimation range(ERG) of any null subcarriers(NSC) placement is further investigated and sufficient and necessary conditions of an NSC allocation that achieves a full ERG are defined.Then,a perfect distributed NSC allocation with the NSC distance larger than coherent bandwidth is devised to fully exploit frequency diversity of wireless channels and achieve a full ERG.Simulations confirmed that the propsoed FFT-based ML method of using this NSC placement has a smaller bandwidth overhead,achieves a fuller ERG and provides a better performance than the existing methods of using the consecutive NSC allocation at middle and high signal-to-noise ratios(SNRs). | SHU Feng BERBER Stevan WANG DongMing ZHANG QinChuan WANG Mao | 2010 | Science China(Information Sciences)2010，53，12： | 8 |
| 4 | 稀疏多径信道环境中MIMO-OFDM系统的IQ不平衡和信道联合估计显示文摘该文针对稀疏多径信道环境中的MIMO-OFDM系统所存在的IQ不平衡问题,提出了一种IQ不平衡参数和信道的联合估计方法。推导了联合估计的时域模型,提出了基于1 2l-l优化模型和平行坐标下降算法的联合估计算法。仿真结果表明,所提方法与传统的频域最小二乘算法和匹配追踪算法相比,显著提高了系统性能。 | 梁彦 束锋 张一晋 Berber Stevan | 2013 | 电子与信息学报2013，35，2： | 8 |
| 5 | 原发性结直肠癌解剖部位在美国白人与中国人之间分布趋势的比较显示文摘目的比较研究美国白人患者与中国患者原发性结直肠癌(CRC)的部位分布特点,并探讨与年龄、性别的关系。方法回顾性分析1990~2000年间美国克里夫兰佛罗里达临床中心结直肠外科690例和中国第一军医大学南方医院普通外科870例连续完整的CRC患者资料。结果CRC部位分布、年龄和性别在美国白人患者和中国患者间差异有显著性意义。位于近侧结肠者为36.3%比26.0%(P<0.001),位于远侧结直肠者为63.7%比74.0%(P<0.001)。近年来,在白人男性中远侧结直肠癌有减少和近侧结肠癌有增加的趋势,80岁以上老年组更明显。在近侧结肠癌中白人男性较女性更常见(P<0.01)。肿瘤分布及性别构成在中国患者中无变化。白人患者平均年龄69.8岁,而中国患者为48.3岁(P<0.001)。结论美国白人较中国人易患近侧结肠癌,其部位分布近年有从远侧向近侧结肠转移而重新分布的趋势。中国人易患远侧结直肠癌,其发病年龄较美国白人明显年轻。 | 卿三华 饶开运 蒋会勇 Stevan D.Wexner | 2002 | 中华胃肠外科杂志2002，5，2： | 7 |
| 6 | 2-甲氧基雌二醇和2-乙氧基雌二醇减少老年肥胖糖尿病ZSF_1大鼠的肾疾病进展显示文摘目的检查2-ME和其一个合成类似物2EE(2-ETHOXYESTRADIOL)对高血压、肥胖和肾脏病进展的影响。方法:实验在35周肥胖ZSF_1大鼠中进行。动物分对照组(PEG-400,0.5μl/ h)和治疗组,2ME,2EE(18μg/kg/h),在0周,3,6和9周时分别测定代谢和肾功能,在9周时评价肾血流动力学和排泄功能。结果2ME,2EE对肥胖和高血压无作用,但可降低糖化血红蛋白和糖尿,防止时间依赖的蛋白尿的增加。2ME和2EE显著增加肾血流和肾小球滤过,减少肾血管阻力;免疫标记肾皮质标本,肥胖动物比同窝出生雄瘦动物有显示增加PCNA,NF-KAPPA B和VEGF的表达。2ME,2EE减少PCNA,NF-KAPPA B和VEGF的表达。结论雌二醇的非雌性激素的代谢物2ME和2EE,对代谢病和肥胖相关的肾病有直接的肾脏保护作用。 | 贾友宏 Xincheng Zhang Edwin K. Jackson Stevan P. Tofovic | 2007 | 中国分子心脏病学杂志2007，7，5： | 4 |
| 7 | Plasma Membrane-Associated SCAR Complex Subunits Promote Cortical F-Actin Accumulation and Normal Growth Characteristics in Arabidopsis Roots显示文摘ARP2/3 建筑群, F 肌动朊聚合的高度保存的 nucleator,和它的使活跃之物, SCAR 建筑群,被显示了在叶起重要作用在 Arabidopsis 的表皮的房间形态发生。然而,疤和 ARP2/3 的细胞内部的地点和功能在植物房间的复杂依赖者的肌动朊聚合仍然保持不清楚。我们证明通常认为的疤建筑群子单元 BRK1 和 SCAR1 在扩展叶子和根的细胞对在细胞生长和墙免职的地点的血浆膜局部性。BRK1 本地化是疤依赖者,提供在在 vivo 的这些蛋白质之间的一个协会的进一步的证据。与疤建筑群子单元的血浆膜本地化一致,在根尖端房间的外皮的 F 肌动朊累积在 brk1 异种被减少。而且,破坏 SCAR 或 ARP2/3 建筑群的变化减少渗透半固体媒介的根和他们的能力的生长率,建议减少的刚硬。变异的根的房间墙在 BRK1 和 SCAR1 在邻近的血浆膜被充实的细胞间的连接展出反常结构和作文。一起拿,我们的结果建议复杂依赖者的肌动朊聚合支持的那个疤和 ARP2/3 在为正常生长和墙汇编是重要的血浆膜处理。 | Julia Dyachok Mon-Ray Shao Kevin Vaughn Andrew Bowling Michelle Facette Stevan Djakovic Lauren Clark Laurie Smith | 2008 | Molecular Plant2008，1，6： | 3 |
| 8 | 二甲酸钾对母猪体况和生长性能的影响显示文摘随着经济的发展和生活水平的日益提高,人们越来越重视和忧虑抗生素的残留和菌株的耐药性问题,消费者对安全绿色健康食品的呼声也愈来愈大,禁抗无抗是全球大势所趋。在目前讨论和研究的方案之中,二甲酸钾(KDF)引起动物营养学界和养猪业的广泛兴趣。欧洲各国对饲料用二甲酸钾的研究开发起源于20世纪90年代中期,1994年在挪威波斯格朗(Porsgrunn)Norsk Hydro的实验室因一次取萃石化用液体甲酸盐的意外,科学家Leif Hj?rnevik发现了沉淀中结晶的二甲酸钾,其在改善畜禽生长性能方面的作用相继被研究报道。2001年7月,欧盟批准了Norsk Hydro开发的Formi LHS(主要成分为二甲酸钾)作为第1个用于猪饲料抗生素促生长剂的代替品(Commission Reg.(EC) No.1334/2001),批准使用的应用范围局限于提高猪的生产性能。由此Formi开启了无抗新纪元,成为后抗生素时代一种可替代猪用生长促进剂。Formi作为无毒害、无残留无抗药性的环保型添加剂的作用越来越为人们所认知,被广大技术专家所推崇。国内外很多KDF的应用实验表明,二甲酸钾作为一种分子式简单的复合盐(具特殊结构的甲酸和甲酸钾),既继承了甲酸的抗菌防霉作用,又具备无腐蚀的缓释效应(单一酸化剂释放过快,在胃中即被全部吸收,无法在小肠部位发挥作用)。具有促进猪的生长,改善仔猪胃肠道消化环境,调节饲料的适口性,提高动物的采食量,有效抑制饲料中的霉菌等有害成分,保持饲料新鲜度和质量,延长饲料的保存期限等一系列作用,且酸化效果优于常用复合型酸化剂。KDF作为非抗生素促生长剂,主要针对断奶仔猪、生长育肥猪及哺乳母猪。文章只重点讨论了KDF饲喂母猪后对饲料采食量,养分消化率,母猪妊娠期至断奶期体况的影响。 | Christian Lückst?dt Stevan Petrovic 李坤杰 | 2019 | 猪业科学2019，36，4： | 2 |
| 9 | The Influence of Culture, Community, and the Nested‐Self in the Stress Process: Advancing Conservation of Resources Theory显示文摘 | Stevan E.Hobfoll | 2001 | Applied Psychology2001，，3： | 2 |
| 10 | The Influence of Culture, Community, and the Nested‐Self in the Stress Process: Advancing Conservation of Resources Theory显示文摘 | Stevan E.Hobfoll | 2001 | Applied Psychology2001，，3： | 2 |
| 11 | 欧洲共同体委员会促进情报服务市场发展的政策显示文摘 | Stevan,G 陈昭楠 | 1993 | 国外情报科学1993，11，3： | 1 |
| 12 | Network Support for IP Traceback 显示文摘 | Stevan Savagel David Wetherall Anna Karlin | 2001 | ACM/IEEE Transactions on Networking(TON)2001，9，3： | 1 |
| 13 | An overview of biomass energy utilization in Vojvodina 显示文摘 | Sinisa N Dodic Stevan D Popov Jelena M Dodie | 2010 | Renewable and Sustainable Energy Reviews2010，14，1： | 1 |
| 14 | Problem Weed control in glypho-sate - resistant soybean with glyphosate tank mixes and soil - applied herbicides显示文摘 | Stevan Z K Datta A Scott J | 2009 | Weed Technology2009，23，： | 1 |
| 15 | The Access/ impact Problem and the Green and Gold Roads to Open Access显示文摘 | Stevan H Brody T Valli~res F | 2004 | Serials Review2004，30，4： | 1 |
| 16 | Ureteropelvic junction obstruction: open operative intervention显示文摘 | Stevan BS | 1998 | Urol Clin North Am1998，25，2： | 1 |
| 17 | Experimental and numericalinvestigation of gaseous fuel combustion in swirl chamber显示文摘 | Stevan N Vukman B Simeon O | 2005 | International Journal of Heat and Mass Transfer2005，48，21： | 1 |
| 18 | α-times integrated semigroups显示文摘 | Milorad Mijatovic Stevan Pilipovic | 1997 | Journal of Mathematical Analysis and Applications1997，210，： | 1 |
| 19 | Orientation of the wood polymers in thecell wall of spruce wood fibres显示文摘 | Stevanic J S Salmon L | 2009 | Holzforschung2009，63，5： | 1 |
| 20 | ”显示文摘 | Harrell Stevan&Sara Dickey “Dowry Systems in Complex Society | 1985 | In Ethnology1985，，24： | 1 |
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