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31.
When a dissimilarity matrix cannot be represented in a Euclidean space, it is possible to make it Euclidean by means of suitable
transformations of the original dissimilarity values. In this paper we discuss some interesting properties of a class of transformations
based on adding a specific squared Euclidean distance to the initial dissimilarity.
An erratum to this article is available at . 相似文献
32.
Hydrological and mechanical properties of plants to predict suitable legume species for reinforcing soil 总被引:1,自引:0,他引:1
Plants have considerable hydrological and mechanical impacts on soil. However, there are lack of documentation and limited understanding on the hydro- logical and mechanical impacts of tropical legume trees. Therefore, this study was aimed to investigate the hydro- logical and mechanical properties of three selected legume plants, Leucaena leucocephala, Adenanthera pavonina and Peltophorum pterocarpum. Regarding hydrological aspect, the study results indicated that soil on which the L. leu- cocephala was grown had the highest transpiration rate, water absorption rate (WAR) and soil matric suction (SMS). In terms of mechanical characteristics, L. leuco- cephala exhibited the highest root tensile strength and cellulosic components in the root. Interestingly, L. leuco- cephala also showed a higher root biomass, root length and fine roots than A. pavonina and P. pterocarpum. The leaf area index (LAI) strongly correlated with SMS (R2 = 0.74), indicating that high LAI improved SMS. The high root tensile strength and fine roots of L. leucocephala make this species special for growing as a soil reinforcing plant. Overall results suggested that L. leucocephala exhibited outstanding hydrological and mechanical prop- erties and can be a potential plant for the soil reinforcement program. 相似文献
33.
Ahmed Mostafa Soliman Neveen Samy Gadallah Michael Ohl Hathal Mohammed Al Dhafer 《Journal of Natural History》2017,51(33-34):2057-2085
The apoid wasps of the families Ampulicidae and Heterogynaidae of Saudi Arabia are revised. In Ampulicidae, four species in three genera are reported, of which three species are recorded for the first time from Saudi Arabia (Al-Baha, Asir and Riyadh regions): Ampulex assimilis Kohl, Dolichurus arabicus Ohl and Trirogma caerulea Westwood. Additionally, the family Heterogynaidae is reported for the first time from Saudi Arabia (Asir and Riyadh regions), and a new species, Heterogyna saudita sp. nov., is described, diagnosed and illustrated. An illustrated key to the species of Heterogyna from the Arabian Peninsula is provided.
www.zoobank.org/urn:lsid:zoobank.org:pub:C23C70A7-AA1C-47C0-951A-D164E7B20001 相似文献
34.
Al-Mayouf SM Sunker A Abdwani R Abrawi SA Almurshedi F Alhashmi N Al Sonbul A Sewairi W Qari A Abdallah E Al-Owain M Al Motywee S Al-Rayes H Hashem M Khalak H Al-Jebali L Alkuraya FS 《Nature genetics》2011,43(12):1186-1188
Systemic lupus erythematosus (SLE) is a complex autoimmune disease that causes substantial morbidity. As is typical for many other multifactorial disorders, much of the heritability of SLE remains unknown. We identified a rare autosomal recessive form of SLE, in which autozygome analysis revealed a null mutation in the DNASE1L3 gene. The DNASE1L3-related SLE we describe was always pediatric in onset and correlated with a high frequency of lupus nephritis. Our findings confirm the critical role of impaired clearance of degraded DNA in SLE pathogenesis. 相似文献
35.
ZHANG Wenbing ABUZAR HUSSEIN MOHAMMED Atitalla BAO Jiatong LIU Yurong 《系统科学与复杂性》2022,35(5):1700-1718
In this paper, the authors study the fully distributed event-triggering consensus problem for multi-agent systems with linear time-varying dynamics, where each agent is described by a linear time-varying system. An adaptive event-triggering protocol is proposed for time-varying multi-agent systems under directed graph. Based on the Gramian matrix of linear time-varying systems, the design of control gain is done and sufficient conditions ensuring the consensus of linear time-varying multiagent s... 相似文献
36.
Education: The PhD factory 总被引:3,自引:0,他引:3
37.
365 days: Nature's 10 总被引:1,自引:0,他引:1
Butler D Callaway E Hayden EC Cyranoski D Hand E Nosengo N Reich ES Tollefson J Yahia M 《Nature》2011,480(7378):437-445
38.
利用石英弹簧称重法测定了308.15K时乙醇和苯在含端羟基聚丁二烯(HTPB)和端羟基聚丁二烯/丙烯腈共聚物(HTBN)的嵌段共聚聚氨酯膜中的吸收动力学曲线。结合吸收-络合吸附双模式传递模型,研究了聚氨酯膜的微相分离程度、软硬段的比例和组成以及软段分子量等因素对溶剂在膜中溶解和传递性质的影响。 相似文献
39.
对正离子表面活性剂烷基三甲基溴化铵(DeTAB、DoTAB、TTAB和CTAB)和负离子表面活性剂十二烷基硫酸钠(SDS)混合体系双水相性质进行了研究.结果表明:313 K下各体系都能形成双水相,且阴、阳离子表面活性剂分别决定着阴、阳离子双水相(ATPSa、ATPSc)的性质.双水相区域中两表面活性剂的配比可能与该区域内富舍表面活性剂胶团化性能有关.胶团化越强,其在双水相中所占的比例越大.实验结果也表明:混合溶液中两表面活性剂链长的匹配扩大了双水相区域的面积,使双水相具有更好的稳定性. 相似文献