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| 1 | Assessment of metastatic liver disease in patients with primary extrahepatic tumors by contrast-enhanced sonography versus CT and MRI显示文摘瞄准:与已知的额外的肝的原发性瘤对包括 CT, MRI 和临床 / 组织学的数据的联合标准答案在病人在肝转移的察觉用 SonoVue 评估提高对比的 ultrasonography (CEUS ) 。方法:它是一国际多集中学习,并且有 12 个中心和 125 个病人(64 男性, 61 女性,变老 59+/-11 年) 包含,与 102 个病人一起每协议。原发性瘤是在 35% 表面的颜色,在 27% 的胸,在 17% 胰腺并且其它在 21% 。用 SonoVue 的 CEUS 用西门子 Elegra, Philips HDI 5000 和 Acuson 红杉与一种 low-mechanical-index 技术和对比特定的软件被采用;为至少五分钟的连续扫描。结果:有 SonoVue 的 CEUS 显著地增加了检测的焦点的肝损害对 unenhanced sonography 的数字。在 31.4% 病人,更多的损害在对比改进以后被发现。检测的损害的全部的数字与 CEUS (55 ) 是可比较的,三倍阶段的螺线 CT (61 ) 和有一个肝特定的对比代理人(53 ) 的 MRI。变形疾病的察觉的精确性(即至少一变形损害) 比为 unenhanced sonography (81.4%) 为 CEUS (91.2%) 是显著地更高的并且类似于三倍阶段的螺线 CT (89.2%) 的。在其 CEUS 检查否定的 53 个病人,后续考试 3-6 瞬间以后在 50 个病人(94.4%) 证实了变形损害的缺席。结论:CEUS 被证明在在有已知的额外的肝的原发性瘤的病人的肝转移的察觉可靠并且怀疑肝损害。 | Christoph F Dietrich Wolfgang Kratzer Deike Strobel Etienne Danse Robert Fessl Alfred Bunk Udo Vossas Karlheinz Hauenstein Wilhelm Koch Wolfgang Blank Matthijs Oudkerk Dietbert Hahn Christian Greis | 2006 | World Journal of Gastroenterology2006，12，11： | 39 |
| 2 | 脊髓神经干细胞的培养和鉴定显示文摘目的 研究脊髓源性神经干细胞的培养和体外分化情况 .方法 采用细胞培养技术结合间接免疫荧光细胞化学法 .结果 1在只有 EGF存在的情况下 ,没有干细胞团的生成 ;而在只有 b FGF存在的情况下 ,有少量干细胞团生成 ;在EGF和 b FGF同时存在时 ,有大量神经干细胞团生成 . 2体外存活时间越长 ,培养中的干细胞成分越多 ,分化后成分越少 . 3随诱导分化时间的加长 ,分化的细胞类型开始出现并增多 ,干细胞比率下降 .结论 脊髓神经干细胞的存活有赖于 EGF和 b FGF的共同作用 ,体外培养 4wk以上的细胞 ,所含的前体细胞的成分较少 。 | 孟晋宏 Udo Bartsch Melitta Schachner 鞠躬 | 2000 | 第四军医大学学报2000，21，8： | 20 |
| 3 | Improved spontaneous erectile function in men with mild-tomoderate arteriogenic erectile dysfunction treated with a nightly dose of sildenafil for one year: a randomized trial显示文摘瞄准:为了测试假设,那 sildenafil (为一年夜里的 50 mg ) 能与 mild-to-moderate arteriogenic 在人改进自发的可勃起的功能(EF ) 可勃起的机能障碍(编辑) 对 erectogenic 处理应答。方法:在未来的开标签的试用,有编辑的 112 个人被使随机化到 sildenafil 夜里的 50 mg 或 sildenafil 需要 for12 月的 50 或 100 mg,由一个月和 6 月的非药物治疗的时期列在后面。非使随机化,有编辑的 non-medicatedmen 也被估计。可勃起的功能(IIEFEF ) 和山峰的国际索引的 EF 领域阴茎多孔的动脉的收缩速度(PSV ) 被用来测量功效。结果:在 sildenafil 处理和一个随后的非药物治疗的月以后, IIEF EF 在 48 中的 29 个是正常的(60.4% , 95% 信心间隔[CI ] :45.3-74.2%) 夜里的组对 4 of49 (8.2% , 95% CI:2.3-19.6%) 同样需要的组。PSV 由 11.2 cm/s 改善了(95% CI:4.7-21.4;P= 0.012 ) 在夜里的组,但是仅仅由 3.4 cm/s (-5.1-14.7;P = 0.435 ) 在同样需要的 group.IIEF, EF 在 18 中的 1 个使正常化(5.6% , 95% CI:0.1-27.3%) 非药物治疗的人和 PSV 稍微拒绝了。在处理,正常的仍然是的 IIEF EF 和 PSV 以后的六个月在大多数被稳定(28/29, 97%) 开始使正常化的夜里的组人。结论:为一年夜里的 Sildenafil 导致了在处理的结束以后坚持了很好的编辑回归,以便 spontaneousEF 在大多数人在 IIEF 上作为正常被描绘。从这开标签的、使随机化的试用的结果在双窗帘下面保证确认,控制安慰剂的条件。 | Frank Sommer Theodor Klotz Udo Engelmann | 2007 | Asian Journal of Andrology2007，9，1： | 12 |
| 4 | Differential changes in intrinsic innervation and interstitial cells of Cajal in small bowel atresia in newborns显示文摘AIM: To investigate morphological changes of the enteric nervous system (ENS) and the interstitial cells of Cajal (ICCs) in small bowel atresia.METHODS: Resected small bowel specimens from affected patients (n = 7) were divided into three parts (proximal, atretic, distal). Standard histology and enzyme immunohistochemistry anti-S100, anti-protein gene product (PGP) 9.5, anti-neurofilament (NF), antic-kit-receptor (CD117) was carried out on conventional paraffin sections of the proximal and distal part. RESULTS: The neuronal and glial markers (PGP 9.5, NF, S-100) were expressed in hypertrophied ganglia and nerve fibres within the myenteric and submucosal plexuses. Furthermore, the submucous plexus contained typical giant ganglia. The innervation pattern of the proximal bowel resembled intestinal neuronal dysplasia. The density of myenteric ICCs was clearly reduced in the proximal bowel, whereas a moderate number of muscular ICCs were found. The anti-CD117 immunore- action revealed additional numerous mast cells. The distal bowel demonstrated normal morphology and density of the ENS, the ICCs and the mast cells.CONCLUSION: The proximal and distal bowel in small bowel atresia revealed clear changes in morphology and density of the ENS and ICCs. | Stefan Gfroerer Roman Metzger Henning Fiegel Priya Ramachandran Udo Rolle | 2010 | World Journal of Gastroenterology2010，16，45： | 9 |
| 5 | 两种麦蚜取食诱导小麦抗性品种后对后来取食蚜生物学特性的影响显示文摘刺吸式昆虫在刺吸作物韧皮部取食后会影响作物的正常生长发育,随着作物抗性及昆虫种类的不同,作物反过来也会对昆虫造成或正或反的影响,然而一种刺吸式昆虫取食后对后来者有什么样的影响目前尚不确定。本研究通过严谨的实验方法,即选定3个不同国家的小麦抗性品种98-10-30、Amigo和Batis,在所有条件严格统一的人工智能控制温室内,通过各处理在同一植株上先后不同的接蚜方式,分别测定了麦二叉蚜Schizaphis graminum(Rondani)和麦长管蚜Sitobion avenaeFab.在前期被蚜虫危害的抗虫品种98-10-30、Amigo和Batis上的发育历期、体重差及相对日均体重增长率(mean relative growthrate MRGR)等生物学参数。结果表明:品种不同,蚜虫在不同处理条件下取食作物时受到的影响也不同,即在品种98-10-30上,通过与前期不接虫的对照及前期接不同麦蚜的相关处理比较,麦长管蚜对后期取食的麦二叉蚜(MRGR=0.0974±0.0071)具有抑制作用,而麦二叉蚜对后期取食的麦长管蚜(MRGR=0.1614±0.0048)却有促进作用;在品种Amigo上,前期麦蚜的危害对麦长管蚜的取食具有促进作用,而在品种Batis上前期危害对麦二叉蚜的取食具有促进作用。同时明确了3个品种对两种蚜虫的抗性状况,即在前期无蚜虫危害时,品种98-10-30和Batis对两种麦蚜的抗性相当;在前期有麦蚜危害时,品种98-10-30对麦二叉蚜的抗性较好,而品种Batis对麦长管蚜的抗性较好;品种Amigo无论在任何处理下均对麦二叉蚜的抗性较好。 | 李军 赵惠燕 Udo HEIMBACH Thomas THIEME | 2007 | 昆虫学报2007，50，2： | 9 |
| 6 | Key Factors Involved in Lamb Quality from Farm to Fork in Europe显示文摘World lamb consumption is approximately 2 kg per capita with large variations between continents,e.g.,17 kg in Oceania vs.0.7 kg in North America.With less than one million tonnes,the international trade of sheep meat contributes to a small percentage of the total meat exchanged between countries.On the other hand,lamb represents the highest rate of species trading in relation to the total sheep meat produced.It is therefore likely to find a wide variability of different lamb products in the same market,and that the conservation procedures(such as refrigeration,packaging or freezing),chemical composition,especially the fat due to its implication in human health,flavour development and juiciness perception(affected,i.e.,by the feeding or the age or slaughter weight of the animal) and acceptability(based on culinary background) could be considered important indicators of this advantageous situation.In this paper some studies related to the aforementioned indicators are discussed. | Carlos Saudo Erica Muela María del Mar Campo | 2013 | Journal of Integrative Agriculture2013，12，11： | 5 |
| 7 | 溶液法制备杂化钙钛矿薄膜过程中核化与晶粒生长动力学控制(英文)显示文摘如何利用溶液法制备高质量、高效率的有机-无机杂化钙钛矿薄膜光电器件,取决于对该体系的核化和晶体生长机理的深入研究.尽管用很多方法可以制备出高性能的钙钛矿薄膜,到目前为止,还缺乏一个准确且统一的模型,去解释钙钛矿晶体是如何从溶液中析出生长的过程.本文通过对晶体核化和生长动力学的详细研究,提出了有机-无机杂化钙钛矿薄膜材料的形成机制.通过精准控制钙钛矿晶粒生长的条件,异质晶核之间的距离能够在几百纳米到几百微米之间调控.我们还发现在晶核周围直径超过100微米范围,聚集着取向高度一致的晶体团簇.但是这些晶体团簇的尺寸大小,与提高钙钛矿光电器件的性能并没有什么直接的对应关系;钙钛矿材料微观结构的形成机理,兼有经典和非经典晶体生长的特征.因此对钙钛矿薄膜生长的深入研究,将有助于进一步控制杂化钙钛矿薄膜的微观结构. | Alexander R.Pascoe 顾钦颖 Mathias U.Rothmann 李蔚 张豫鹏 Andrew D.Scully 林雄峰 Leone Spiccia Udo Bach 程一兵 | 2017 | Science China Materials2017，60，7： | 5 |
| 8 | Two strategies for prevention of cytomegalovirus infections after liver transplantation显示文摘AIM: To analyze differences in patients' clinical course, we compared two regimes of either preemptive therapy or prophylaxis after liver transplantation.METHODS: This retrospective study was reviewed and approved by the institutional review board of the University of Leipzig. Cytomegalovirus(CMV) prophylaxis with valganciclovir hydrochloride for liver transplant recipients was replaced by a preemptive strategy in October 2009. We retrospectively compared liver transplant recipients 2 years before and after October 2009. During the first period, all patients received valganciclovir daily. During the second period all patients included in the analysis were treated following a preemptive strategy. Outcomes included one year survival and therapeutic intervention due to CMV viremia or infection.RESULTS: Between 2007 and 2010 n = 226 patients underwent liver transplantation in our center. n = 55 patients were D^+/R^- high risk recipients and were excluded from further analysis. A further 43 patients had to be excluded since CMV prophylaxis/preemptive strategy was not followed although there was no clinical reason for the deviation. Of the remaining 128 patients whose data were analyzed, 60 receivedprophylaxis and 68 were treated following a preemptive strategy. The difference in overall mortality was not significant, nor was it significant for one-year mortality where it was 10%(95%CI: 8%-28%, P = 0.31) higher for the preemptive group. No significant differences in blood count abnormalities or the incidence of sepsis and infections were observed other than CMV. In total, 19 patients(14.7%) received ganciclovir due to CMV viremia and/or infections. Patients who were treated according to the preemptive algorithm had a significantly higher rate risk of therapeutic intervention with ganciclovir [n = 16(23.5%) vs n = 3(4.9%), P = 0.003)].CONCLUSION: These data suggest that CMV prophylaxis is superior to a preemptive strategy in patients undergoing liver transplantation. | Philipp Simon Max Sasse Sven Laudi David Petroff Michael Bartels Udo X Kaisers Sven Bercker | 2016 | World Journal of Gastroenterology2016，22，12： | 5 |
| 9 | Complications of newborn enterostomies显示文摘AIM To evaluate the occurrence and severity of enterostomy complications in newborns suffering from different intestinal disorders.METHODS A 10-year retrospective cohort study(2008-2017) investigated newborns that underwent enterostomy formation and reversal for different intestinal disorders. Only infants less than 28 d old at the time of enterostomy creation were included in the study(corrected age was applied in the cases of preterm neonates). The patients were divided into two groups according to their underlying diseases. Group 1 included infants suffering from necrotizing enterocolitis(NEC), whereas Group 2 included newborns diagnosed with intestinal disorders other than NEC, such as meconium obstruction, anorectal malformation, focal intestinal perforation, ileus, intestinal atresia and volvulus. The primary outcome measure was enterostomy-related morbidity. The data were analyzed statistically using Pearson's χ2 test or Fisher's exact test for categorical variables and the Wilcoxon-Mann-Whitney U-Test for continuous variables. RESULTS In total, 76 infants met the inclusion criteria and were evaluated for enterostomy-related complications. Neither group showed significant differences regarding gender, gestational age, weight at birth or weight at enterostomy formation. Infants suffering from NEC(Group 1) were significantly older at enterostomy for-mation than the neonates of Group 2 [median(range), 11(2-75) d vs 4(1-101) d, P = 0.004)]. Significantly more ileostomies were created in Group 1 [47(92.2%) vs 16(64.0%), P = 0.007], whereas colostomies were performed significantly more often in Group 2 [2(3.9%) vs 8(32.0%), P = 0.002]. The initiation of enteral nutrition after enterostomy was significantly later in Group 1 infants than in Group 2 infants [median(range), 5(3-13) vs 3(1-9), P < 0.001]. The overall rate of one or more complications in patients of both groups after enterostomy formation was 80.3%, with rates of 86.3% in Group 1 and 68.0% in Group 2(P = 0.073). Most patients suffered from two complications(23.7%). Four or more complications occurred in 21.6% of the infants in Group 1 and in 12.0% of the infants in Group 2(P = 0.365). Following enterostomy closure, at least one complication was observed in 26.0% of the patients(30.6% in Group 1 and 16.7% in Group 2, P = 0.321). The occurrence of complications was not significantly different between neonates with NEC and infants with other intestinal disorders. 48(65.8%) patients required no treatment or only pharmacological treatment for the complications that occurred [Clavien-Dindo-Classification(CDC) < Ⅲ], while 25(34.2%) required surgery to address the complications(CDC ≥Ⅲ). Early reversal of the enterostomy was performed significantly more often(P = 0.003) and the time to full enteral nutrition after closure was significantly longer [median(range), 7(3-87) d vs 12(5-93) d, P = 0.006] in infants with a CDC grading ≥Ⅲ than in infants with a CDC grading < Ⅲ. CONCLUSION Complications occur in almost all infants with enterostomies. The majority of these complications are minor and do not require surgical treatment. There is a clear trend that neonates with NEC have a higher risk for developing complications than those without NEC. | Lea Wolf Stefan Gfroerer Henning Fiegel Udo Rolle | 2018 | World Journal of Clinical Cases2018，6，16： | 5 |
| 10 | Evolution of germination strategy in the invasive species Ulex europaeus显示文摘Aims The study of the adaptive potential of the germination patterns of invading species enables us to identify some traits linked with their capacity to colonize new sites,and to gain a better understanding of their area of distribution.The aim of this study is to determine the germination pattern of Ulex europaeus,a cosmopolitan invasive species,in relation to temperature and to explore its potential evolu-tion and invasiveness in a tropical region,following its introduction from Europe.Methods We studied the germination pattern of U.europaeus(the com-mon gorse)to test both physical dormancy and germination capacity within the range of temperatures found in the native and invasive regions.To understand its germination pattern and its evolution,the rate and the speed of germination,as well as the percentage of seeds that became mouldy during the experi-ment,have been compared between a native habitat,France and a habitat into which it has been introduced,the tropical island of La Reunion.Important Findings The results show that gorse seeds germinate in large quantities,pos-sess the ability to germinate under a wide range of temperatures and they confirm the physical dormancy of the seeds(caused by seed coat impermeability).The decrease in germination from 25℃ upwards,coupled with an increase in the rate of moulding help to explain its restricted distribution at altitude in tropical environments.For scari-fied seeds,we have not detected any difference between the two regions,neither in the percentage of germinated seeds,nor in the per-centage of mouldy seeds.However,seeds from Reunion germinate faster at 20℃ than seeds from France and a greater number of seeds from Reunion are able to germinate without scarification(10-60%for Reunion versus 0-10%for France).These results suggest that while preserving the advantages of the native habitat,in Reunion gorse develops a strategy which favours the rapid occupation of new sites. | Nathalie Udo Michèle Tarayre Anne Atlan | 2017 | Journal of Plant Ecology2017，10，2： | 4 |
| 11 | Decreasing nutrient concentrations in soils and trees with increasing elevation across a treelineecotone in Rolwaling Himal, Nepal显示文摘At a global scale, tree growth in alpine treeline ecotones is limited by low temperatures. At a local scale, however, tree growth at its upper limit depends on multiple interactions of influencing factors and mechanisms. The aim of our research was to understand local scale effects of soil properties and nutrient cycling on tree growth limitation, and their interactions with other abiotic and biotic factors in a near-natural Himalayan treeline ecotone. Soil samples of different soil horizons, litter, decomposition layers, and foliage samples of standing biomass were collected in four altitudinal zones along three slopes, and were analysed for exchangeable cations and nutrient concentrations, respectively. Additionally, soil and air temperature, soil moisture, precipitation, and tree physiognomy patterns were evaluated. Both soil nutrients and foliar macronutrient concentrations of nitrogen(N), magnesium(Mg), potassium(K), and foliar phosphorus(P) decrease significantly with elevation. Foliar manganese(Mn) concentrations, bycontrast, are extraordinarily high at high elevation sites. Potential constraining factors on tree growth were identified using multivariate statistical approaches. We propose that tree growth, treeline position and vegetation composition are affected by nutrient limitation, which in turn, is governed by low soil temperatures and influenced by soil moisture conditions. | Simon DROLLINGER Michael MULLER Timo KOBL Niels SCHWAB Jurgen BOHNER Udo SCHICKHOFF Thomas SCHOLTEN | 2017 | Journal of Mountain Science2017，14，5： | 4 |
| 12 | Statistical analyses of Global U-Pb Database 2017显示文摘The method of obtaining zircon samples affects estimation of the global U-Pb age distribution.Researchers typically collect zircons via convenience sampling and cluster sampling.When using these techniques,weight adjustments proportional to the areas of the sampled regions improve upon unweighted estimates.Here,grid-area and modern sediment methods are used to weight the samples from a new database of 418,967 U-Pb ages.Preliminary tests involve two age models.Model-1 uses the most precise U-Pb ages as the best ages.Model-2 uses the^(206)Pb/^(238)U age as the best age if it is less than a1000 Ma cutoff,otherwise it uses the^(207)Pb/^(206)Pb age as the best age.A correlation analysis between the Model-1 and Model-2 ages indicates nearly identical distributions for both models.However,after applying acceptance criteria to include only the most precise analyses with minimal discordance,a histogram of the rejected samples shows excessive rejection of the Model-2 analyses around the1000 Ma cutoff point.Because of the excessive rejection rate for Model-2,we select Model-1 as the preferred model.After eliminating all rejected samples,the remaining analyses use only Model-1 ages for five rock-type subsets of the database:igneous,meta-igneous,sedimentary,meta-sedimentary,and modern sediments.Next,time-series plots,cross-correlation analyses,and spectral analyses determine the degree of alignment among the time-series and their periodicity.For all rock types,the U-Pb age distributions are similar for ages older than 500 Ma,but align poorly for ages younger than 500 Ma.The similarities(>500 Ma)and differences(<500 Ma)highlight how reductionism from a detailed database enhances understanding of time-dependent sequences,such as erosion,detrital transport mechanisms,lithification,and metamorphism.Time-series analyses and spectral analyses of the age distributions predominantly indicate a synchronous period-tripling sequence of^91-Myr,~273-Myr,and^819-Myr among the various rock types. | Stephen J.Puetz Carlos E.Ganade Udo Zimmermann Glenn Borchardt | 2018 | Geoscience Frontiers2018，9，1： | 4 |
| 13 | 2013 ESC guidelines on the management of stable coronary artery disease显示文摘 | Gilles Montalescot Udo Sechtem Stephan Achenbach Felicita Andreotti Chris Arden Andrzej Budaj Raffaele Bugiardini Filippo Crea Thomas Cuisset Carlo Di Mario J. Rafael Ferreira Bernard J. Gersh Anselm K. Gitt Jean-Sebastien Hulot Nikolaus Marx Lionel H. Op | 2013 | European Heart Journal2013，，38： | 4 |
| 14 | 环境中的药物——LC-MS/MS分析地表水和地下水显示文摘 | Alida(Linda)AM Stolker Willem Niesing Frank Bakker Johanna(Ans)FM Versteegh Elbert A Hogendoorn Udo A Th Brinkman | 2007 | 环境化学2007，26，4： | 4 |
| 15 | Knowledge of the Firm, Combinative Capabilities, and the Replication of Technology显示文摘 | Bruce Kogut Udo Zander | 1992 | Organization Science1992，，3： | 4 |
| 16 | Mountain Pastures and Grasslands in the SW Tien Shan,Kyrgyzstan-Floristic Patterns,Environmental Gradients,Phytogeography,and Grazing Impact显示文摘Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain agriculture of local farmers.Accordingly,these pastures are subject to an increasing utilization pressure reflecting the changing political and social conditions in the transformation process from a Soviet republic to an independent state.A first detailed analysis of mountain pasture vegetation in the Ferghana Range answers the following questions:What are the main plant community types among Kyrgyzstan's mountain pastures? What are the main environmental gradients that shape their species composition? Which phytogeographical distribution types are predominant? How does grazing affect community composition and species richness in these grasslands? Species composition was classified by cluster analysis;underlying environmental gradients were explored using DCA.A dataset of 395 relevés was used for classification,and a subset of 79 relevés was used in a DCA to analyze the correlation between vegetation,environment,and grazing impact.The investigated pastures were classified into four distinctive plant communities.The site factors altitude,heat load,inclination and grazing impact were found to be the major determinants of the vegetation pattern.A significant overlap between floristic composition and structural and spatial properties was shown.The majority of the species pool consisted of Middle Asian endemics and Eurosiberian species.However,disturbance-tolerant species played a significant role with respect to species composition and coverage of the herbaceous layer in vast areas of southern Kyrgyzstan's mountain pastures.In general,an intense grazing impact is clearly reflected by both species composition and structural variables of plant communities.The highly diverse and unique ecosystem is modified by an increasing utilization pressure.In order to maintain vital processes and functioning of this valuable ecosystem-in both economical and ecological terms-,it is indispensable to adopt appropriate pasture management strategies. | BORCHARDT Peter SCHICKHOFF Udo SCHEITWEILER Sabrina KULIKOV Maksim | 2011 | Journal of Mountain Science2011，8，3： | 4 |
| 17 | Separating polydisperse particles using electrostatic precipitators with wire and spiked-wire discharge electrode design显示文摘 | Soren Sander Steffen Gawor Udo Fritsching | 2018 | Particuology2018，16，3： | 3 |
| 18 | Phase I study of matuzumab in combination with 5-fluorouracil, leucovorin and cisplatin (PLF) in patients with advanced gastric and esophagogastric adenocarcinomas显示文摘 | Tanja Trarbach Marta Przyborek Norbert Schleucher Steffen Heeger Christian Lüpfert Udo Vanhoefer | 2013 | Investigational New Drugs2013，，3： | 3 |
| 19 | Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change显示文摘Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths(3700-4200 m) at 50 plots in 2013 and 2014. We quantified species-environment relationships, i.e. the change ofenvironmental conditions(e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species-environment relationships suggest that the investigated krummholz belt will largely prevent theupward migration of other tree species and thus constrain the future response of Himalayan krummholz treelines to climate warming. | Niels SCHWAB Udo SCHICKHOFF Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND | 2017 | Journal of Mountain Science2017，14，3： | 3 |
| 20 | Particle penetration in fiber filters显示文摘Particle separation from gases is an important unit operation in manifold industrial applications,such as those conducted in environmental protection.For analysis of particle penetration and separation in fiber filters,standard dust particles (Al2O3)were loaded in the gas flow of a filter test facility and deposited within new and uncharged fiber filters.The loaded filters were analyzed by micro-computer tomography and scanning electron microscopy.Three-dimensional tomograms of the samples show an exponential decay of the penetration depth of the particles.This dependency is confirmed by simulations conducted using the discrete element method coupled with computational fluid dynamics within unloaded and loaded fiber structures.Microscale processes of particle separation at the fibers as well as the filtration efficiency and time-dependent filtering process are derived from the simuiations.Local particle clustering in the filter medium and partial filter clogging are thus identified. | Norbert Riefler Martina Ulrich Marko Morshaiuser Udo Fritsching | 2018 | Particuology2018，16，5： | 3 |
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