Statural growth in known-age African elephants (Loxodonta africana)

The shoulder heights of 224 females and 170 males, and hindfoot length of 236 female and 217 male known-age African elephants ( Loxodonta africana ) were measured, and growth curves constructed for each measure of size. A linear relationship between foot length and shoulder height was confirmed in simultaneous measures of 97 males and 110 females. Growth curves demonstrated the typical sexual dimorphism in both foot length and shoulder height, with males growing more rapidly than females from birth onwards. The size dimorphism in foot length and shoulder height becomes marked by the age of 10 years, with males on average being 60–70 cm taller than females at 65 years. This size dimorphism is produced through faster growth which continues for longer than does that of females. The variance in growth rates is slightly greater for females than for males. It is proposed that female growth after puberty is affected by a trade-off between growth and reproduction, while males who deviate markedly from typical patterns of growth may be subject either to mortality or energetic constraints limiting their potential variance.     

A multivariate approach to the selection of biological reserves

Multivariate analysis provides an effective context for the examination of some significant aspects of biodiversity and conservation. The framework is a multidimensional space that integrates sample sites, taxa and environments. This approach enables terms such as representativeness, complementarity and irreplaceability to be integrated within an intuitive and practical framework for reserve design. Cluster analysis is proposed to determine what is there by defining a set of complementary clusters. These clusters are sampled in a representative manner; from the core outward. The degree of irreplaceability of a site is defined as the multivariate distance of each potential reserve site to its nearest neighbour.     

库蠓属的两个新种(双翅目:蠓科)

1982年在四川省采集吸血蠓时,发现库蠓属(culicoides)两个新种。现记述如下。新种模式标本分别保藏于四川省成都铁路局中心卫生防疫站和中国科学院动物研究所。     

Structure and Process in the Interpretation of South American Myth: The Arawak Dog Spirit People

Recent work on oral narrative has emphasized differences in textual and performative approaches, which in turn has tended to widen the distinction between two fundamental categories of anthropological thought: structure and process. This paper argues that, at least for the interpretation of South American myth, an integrated approach is essential. After reviewing the epistemological basis of current problems in myth studies, the paper attempts a structural analysis of myths with the theme of a metamorphic conjugal union between human and nonhuman. Processual considerations are introduced in the form of syncretic myth, and the argument is advanced that there exist syncretic transformations of a structural nature. Identifying these provides the beginnings of a bridge between structure and process, and leads to an examination of the performative context of the subject myth. Other narrative genres, dealing with explicitly ethnic concepts, are implicated in the processual sequence of the telling and interpretation of the tale. The attempted synthesis of structure and process in narrative analysis leads to an engagement with two difficult problems: the relationship between ethnicity and kinship; and the transition from myth to history. [myth, structure, process, ethnicity, kinship]     

Inhibitory activity of palladium(II) and platinum(II) complexes with isoxazole and its derivatives

The investigation of the inhibitory activity on the membrane bonded ATP-ase of the M(L)₂X₂ complexes [where M = Pd(II), Pt(II); L = isoxazole(isox), 3,5-dimethylisoxazole(3,5-diMeisox), 3-methyl,5-phenylisoxazole(3-Me,5-Phisox), 3,5-diphenylisoxazole-(3,5-diPhisox), and 4-amino-3,5-dimethylisoxazole(4-ADI); X = Cl, Br] is reported. These results show that the complexes with isox and its methyl and phenyl derivatives have a much stronger inhibitory effect than the corresponding free ligands; in the 4-ADI compounds this activity drops. The Pd(II) complexes have a greater effect than the Pt(II) derivatives. The interaction occurs with SH groups and probably also with other active centers of the enzyme. These conclusions have been correlated with the E.S.C.A. spectra. These measurements show that the electron density of the complexes on the central metal ion and N_ring atom or N_ring and N-hexocyclic atoms on passing from chloride to bromide derivatives changes slightly.     

Taxonomy and Description of Vibrio fluvialis sp. nov. (Synonym Group F Vibrios, Group EF6)

A numerical taxonomic study has been carried out to establish the relationship of group F to other biochemically similar organisms within the family Vibrionaceae. A total of 154 strains were examined including 59 of group F. Out of 114 characters determined for each strain 100 were used to compute average Euclidean distances between strains. Four methods of clustering were used, all of which gave very similar results.
Strains resembling Vibrio anguillarum fell into clusters corresponding to V. anguillarum, Beneckea nereida and a previously unrecognized group, phenon 5. Strains of the Aeromonas hydrophila/punctata group formed a heterogenous phenon within which certain subdivisions, perhaps artificial, could be discerned.
Group F strains all fell in one closely-knit cluster distinct from all the species of Vibrio, Aeromonas, Plesiomonas and Photobacteriwn studied. Group F strains could be divided into two biovars, I and II. Both biovars are present in aquatic, particularly estuarine, environments throughout the world but biovar I strains have also been isolated from humans with diarrhoea. It is concluded that group F is a synonym of group EF6 and that the strains within these groups should be classified in a new species named Vibrio fluvialis. The type strain is NCTC 11327.     

Chasmogamous and Cleistogamous Pollination in Salpiglossis sinuata

Pollen from chasmogamous flowers of Salpiglossis sinuata L. could not be induced to germinate in vitro unless stigmatal extract was applied to the culture medium. The substance that induces pollen germination in the stigmatal extract is water-soluble and heat-stable. Crosses could not be achieved between chasmogamous and cleistogamous flowers because of structural incompatibility. Pollinated pistils of chasmogamous flowers release a large amount of ethylene. The burst of ethylene release is due to an interaction between pollen tubes and stylar tissue and is directly proportional to the quantity of pollen placed on the stigma. Cleistogamous flower buds also produce a burst of ethylene at the time of pollination within the closed flower. The ethylene release may be a cause of reduced corolla development associated with cleistogamous flowers.     

Fine-structural Alterations in Leishmania tropica within Human Macrophages Exposed to Antileishmanial Drugs in Vitro1

The mechanism of action of antileishmanial compounds is poorly understood. Ultrastructural changes in Leishmania tropica within human macrophages exposed in vitro to Pentostam, pentamidine, amphotericin B, WR 6026, ketoconazole, and Formycin B were examined in these experiments. In Pentostam-treated cultures, some organisms exhibited diminished definition of mitochondrial and other membranes, while other organisms had completely disintegrated. Pentostam-exposed macrophages demonstrated loss of membrane definition in the absence of further alterations; it is therefore hypothesized that impaired macrophage membrane function may contribute towards the effect of this drug against macrophage-contained organisms. Leishmania parasites in pentamidine-treated cultures initially demonstrated swollen kinetoplasts and fragmentation of the kinetoplast DNA core. The initial observed effect of the other four drugs on the parasites was cytoplasmic condensation. These ultrastructural studies suggest that all five non-antimonial drugs may have different mechanisms of action than antimony (Pentostam) against Leishmania.     

Amphipod crustaceans as an important component of zoobenthos of the shallow Antarctic sublittoral

Benthic quantitative samples were taken in 1988 in the soft bottom sublittoral of Admiralty Bay (King George Island, South Shetlands) using a Tvärminne-type bottom sampler and SCUBA-diving technique at 7 successive stations situated at depths from 4 to 30 m.Dominant animal groups in terms of abundance were Amphipoda, Polychaeta and Bivalvia, whereas in terms of biomass Echinoidea were also dominant. Amphipod crustaceans clearly dominated the zoobenthos at depths from 10 to 25 m (the numerical share surpaising 60%) with maximal abundance of abt. 17 000 ind m^–2; in terms of biomass at specific depths amphipods occupied the 1st, 2nd or 3rd place with maximal biomass of abt. 100 g m^–2 where the maximal total biomass of zoobenthos reached 260 g m^–2 (10 m).Amphipoda were the most diversified group with some 35 taxa belonging to 14 families. Most species belonged to Eusiridae s.l. and Lysianassidae s.l. Dominant forms were Pontogeneiella brevicornis, Prostebbingia gracilis, Schraderia gracilis, Hippomedon kergueleni, Orchomenella cf. ultima, Cardenio paurodactylus and Paraphoxus rotundifrons.     

Liverwort genomes display extensive structural variations

PIKE, L. M., HU, A., RENZAGLIA, K. S. & MUSICH, P. R., 1992. Liverwort genomes display extensive structural variations. Analyses of the total genomic DNA of eight species of liverworts and two species of green algae by thermal denaturation and CsCl buoyant density gradient centrifugation reveal a high degree of structural complexity and interspecific heterogeneity. The hepatic taxa exhibit two or more DNA components of varying base composition. Average G4-C contents of total cellular DNA calculated from melting profiles are similarly variable, ranging from 38% to 53% G + C. The green alga Chara , a member of the ancestral line to land plants, shows similarities with liverworts in possessing multiple DNA components of comparable complexity, whereas Hydrodiciyon DNA displays a single component. Detailed hybridization analyses of individual density gradient fractions using α-tubulin, rRNA and ribulose 1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene probes were performed to locate the low-copy number and moderately repetitive nuclear genes, and the chloroplast chromosome, respectively. The location of each gene within the density gradient is highly variable among the organisms examined; a-tubulin occurs in fractions ranging from 44–64% G + C, rDNA in 50–64% G + C fractions, and the RbcL gene is located in fractions from 30–59% G + C. For a given species, the two nuclear genes normally overlap in their distributions within the gradient. In most instances, neither gene occurs in the major DNA components, indicating that these components may contain repetitive DNAs. The observed variation in the density of the rbcL gene implies substantial reorganization of the chloroplast genome. The overall differences in the genomic components within and between taxa provide insight into the dynamics of DNA structure that have occurred during the extended evolutionary history of these organisms.