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1.
Flowers and leaves of Disynaphia multicrenulata from Argentina afforded a large number of known germacradienolides and heliangolides, a new germacradienolide, a known melampolide, a new parthenolide derivative, one known and seven new cronquistiolides, a new 4Z-melampolide, three known and five new eudesmanolides, a new elemadienolide, a known grazielolide, an isoguaiagrazielolide, two diepoxygermacran-8,12-olides, three common kauranoic acids, pinoresinol, jaceosidin and the sesquiterpene oplopanone. Structures were elucidated by high-field 1H NMR spectrometry. The relationship to the known chemistry of other members of the Disynaphiinae is discussed.  相似文献   

2.
The hypothesis of a qualitative new field permits the prediction of a new fundamental constant. With this constant a relation between c and h can be found. The new constant permits not only a system of physics but also a new transition from physics into biology.  相似文献   

3.
Aerial parts of Centaurea tweediei from Argentina afforded as the main constituent the sesquiterpene lactone onopordopicrin and minor amounts of a new heliangolide, a new guaianolide, a new eudesmanolide, a new eudesmane acid and the lignans arctigenin and matairesinol.  相似文献   

4.
In anticipation of the publication of full revisions, a diagnosis of a new species of Droguetia is presented together with two new combinations for subspecies of Droguetia iners , a new combination for a species and a variety on Didymodoxa and a new combination for a subspecies of Australina pusilla . The name Elatostema trinerve Hochst. (1845) is shown to be conspecific with and antedate Urera cameroonensis Wedd. (1869). The new combination Urera trinervis is therefore made.  相似文献   

5.
赵冰  龚梅香  张启翔 《植物研究》2007,27(2):131-132
描述了蜡梅(Chimonanthus praecox L.)一新变种即卷瓣蜡梅,该变种与原变种的主要区别是中花被片高度反卷,中被片颜色为白色或金黄色,主要分布于神农架林区。其中中被片颜色为白色的卷瓣蜡梅可以被看作一个新变型跳枝蜡梅。  相似文献   

6.
本文记述同翅目蚧总科粉蚧科一新属一新种。即异星粉蚧属Heteroheliococcus gen.nov.,内蒙异星粉蚧H.innermongolicus sp.nov.。新种模式标本保存在山西农业大学蚧虫研究中心。  相似文献   

7.
A higher category is the result of a population's breaking-throuh into a new adaptive zone (attaining a new grade), and the subsequent adaptive radiation tiere. The taxonomic level of the new group is determined by the amount (quantitative and ualitative) of radiation that occurs; and tgis amount in turn is determined by the number of open sub-zones in the new zone and by the genetic plasticity of the new population. The more the new adaptive zone differs from the old one, the less likely a new population can survive in it. Should such survival occur, however, adaptations of the new population to the new zone will appear quickly. The new population will rapidly become quite different from the old one, minimizing the likelihood of finding intermediate forms, i. e., “missing links.” In addition, the intermediate population – the early entrants into the new zone – will be less well adapted to it than their descendents, and will become extinct. The combination of rapid extinction and an ephemeral transitional population explains the apparent gaps between higher-category taxa. These ideas do not help in solving such dilemmas of taxonomists as equivalence of taxa in different groups, and the taxonomic level at which to place a given group of species. But a higher taxonomic category itself is the result of a very real biological phenomenon, and that fact must influence systematicists.  相似文献   

8.
Summary A new modified Square Root model and two new modified Schoolfield models were evaluated for their ability to predict the growth rate ofYersinia enterocolitica as a function of temperature. The new Square Root model fits the data better than both the original Square Root model and the Zwietering Square Root model. Both new Schoolfield models, a six-and a four-parameter equation, fit the data better than the original Schoolfield model. The new four-parameter Schoolfield model was developed by removing the term describing low temperature inactivation from the new six-parameter Schoolfield model. Inclusion of the two extra parameters in the new six-parameter Schoolfield model (F=318) did not significantly improve the fit compared to the new fourparameter Schoolfield model (F=488).  相似文献   

9.
On prediction of genetic values in marker-assisted selection.   总被引:13,自引:0,他引:13  
C Lange  J C Whittaker 《Genetics》2001,159(3):1375-1381
We suggest a new approximation for the prediction of genetic values in marker-assisted selection. The new approximation is compared to the standard approach. It is shown that the new approach will often provide substantially better prediction of genetic values; furthermore the new approximation avoids some of the known statistical problems of the standard approach. The advantages of the new approach are illustrated by a simulation study in which the new approximation outperforms both the standard approach and phenotypic selection.  相似文献   

10.
Anticipating a complete revision of the genus Xanthophyllum , which will be printed in Blumea within two years, one new subgenus, 17 new species, one new subspecies and two new varieties are described, and for three names a new status is proposed. This is done for nomenclatural reasons, validating the new names in W. C. Dickison's study of the leaf anatomy of Xanthophyllum , published elsewhere in this Journal.  相似文献   

11.
We describe here two new species of oegopsid squids. The first is an Asperoteuthis (Chiroteuthidae), and it is based on 18 specimens. This new species has sucker dentition and a funnel–mantle locking apparatus that are unique within the genus. The second new species is a Promachoteuthis (Promachoteuthidae), and is based on a unique specimen. This new species has tentacle ornamentation which is unique within the genus. We also describe a new genus and a new species of sepioid squid in the subfamily Heteroteuthinae (Sepiolidae) and it is based on four specimens. This new genus and species exhibits unique modifications of the arms in males.  相似文献   

12.
The behavioural response of the brown spiny mouse, Mus platythrix Bennett to new place and new object was studied in a plus (+) maze. The new place reaction was observed by allowing the mice to access an area which had previously been not exposed to them and the new object reaction was studied by introducing a change at the feeding point. The experiment suggested new place philia and new object philia in this species.  相似文献   

13.
云南蕨类植物小志   总被引:4,自引:1,他引:3  
根据PYU(云南大学蕨类植物标本室)保存的标本,报道云南蕨类植物若干新资料,内容为:3新种,2新变种,中国分布新记录2种,云南分布新记录1属3种,1个种的新组合名称,另1个种的属、科位置的订正及其新组合名称。  相似文献   

14.
Some new micromycetes from New Zealand   总被引:1,自引:0,他引:1  
New collections of micromycetes from New Zealand are recorded, including several new species and a new variety of the genera Cercospora, Entylomella, Gonatophragmium, Pseudocercospora, Ramularia and Subramaniomyces as well as some new combinations and a new name. Based on a new generic concept of the Pseudocercospora/Cercostigmina complex, which is supported by new molecular examinations, all species of Cercostigmina are re-allocated to Pseudocercospora.  相似文献   

15.
Rupert Barneby had 263 publications (two of which were published with two volumes each) during his career (including 56 book reviews), and additionally published new taxa and combinations in 16 publications by B. A. Krukoff, S. L. Welsh, and A. Lourteig. In total, these publications amount to 7676 pages. Each entry was examined, was dated as accurately as possible, and was annotated with any new nomenclauture presented in the publication. Barneby published 4 new subtribes within the legumes, 9 new genera of legumes (one based on a new combination) and 6 new genera of Menispermaceae, 621 new species (including 6 new nothospecies), 16 new subspecies, 355 new varieties, and 1 new form. Additionally, he published 238 new infrageneric taxa (subgenera, sections, or subsections). he made numerous new combinations (including nomina nova) at the infrageneric level (169), the species level (582), the subspecific level (27), and the varietal level (533), as well as a single combination at the form level.  相似文献   

16.
Americabaetis (Insecta: Ephemeroptera: Baetidae), previously considered synonymous with Acerpenna, is reinstated and given generic rank. The genus differs from Acerpenna in lacking hindwings, gills on abdominal segment 1, and a conical process between the male genital forceps, and in possessing apically rounded gills on abdominal segment 7. The genus has a general Neotropical distribution with a northern limit in east-central Mexico. Five new species of Americabaetis are described from South America: A. alphus, new species, from Argentina, Bolivia, Brazil, Chile, and Paraguay; A. labiosus, new species, from Brazil, Paraguay, and Uruguay; A. longetron, new species, from Brazil, Paraguay, and Uruguay; A. maxifolium, new species, from Paraguay; and A. titthion, new species, from Brazil. Americabaetis boriquensis, new combination; A. intermedius, new combination; A. naranjoi, new combination; A. pleturus, new combination; and A. robacki, new combination, are reviewed.  相似文献   

17.
This paper represents new discoveries of the genus Hippophae L, including two new sections: i. e. Sect. I. Hippophae and Sect. II. Gyantsenses Lian, a new rank species H. gyantsensis (Rousi) Lian, as well as a new record of H. rhamnoides L. subsp. turkestanica Rousi in Gansu. Besides, a key to the sections and species is provided and an account of the new classification scheme on the genus is given.  相似文献   

18.
R Rothstein  R Wu 《Gene》1981,15(2-3):167-176
The construction of two new derivatives of the bacteriophage cloning vector M13mp2 is described. One derivative, mWJ22, contains a new HindIII site while the other, mWJ43, contains a new BamHI site. These new sites were both introduced at the EcoRI site at amino acid five of the 145 amino acid-long fragment of Escherichia coli beta-galactosidase within the phage. The new restriction sites do not disrupt the blue color detection system of M13mp2; therefore insertion of cloned fragments results in colorless plaques on indicator plates for the new derivatives.  相似文献   

19.
本文对广东滩涂经济鱼类寄生复殖吸虫中的单孔科HaploporidaeNicoll,1914,单胜科HaplosplanchnidaePoche,1926和八睾科OctotestidaeYamaguti,1971吸虫进行研究,其中长尾亚科Elonainurinae和鲻长尾吸虫Elonginurusmuugilus分别作为单孔科的新亚科和新属新种;雄囊新单脏吸虫Neohaplosplanchnuscirrusaci作为单脏科的新属新种;天竺鲷八睾吸虫Octotestisapogoni作为八睾科、八睾吸虫属Octotestis(Wang,1963)Yamaguti,1951的新种。  相似文献   

20.
值得注意的中国植物   总被引:2,自引:0,他引:2  
张宏达  丘华兴   《广西植物》1999,19(3):193-196
近年为研究中国的大戟科、檀香科等科的植物,对中山大学生物系植物标本馆(SYS)、华南植物研究所标本馆(IBSC)等的标本予以重新鉴定.现将中国植物区系中一些属或种作必要的修订,增加《中国植物志》未收载的2个新记录种,处理1个新异名.  相似文献   

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