Soil depth shapes plant functional diversity in granite outcrops vegetation of Southwestern Australia

Background: The arid and nutrient-poor Southwestern Australia is one of the global biodiversity hotspots. Embedded in this landscape, granite outcrops are considered terrestrial insular habitats supporting habitat heterogeneity when compared to the more homogenous surrounds. Ecology of plant species and communities on granite outcrops has been addressed in numerous studies. However, functional diversity (FD) in context of the environmental heterogeneity remained unexplored.

Aims: We tested whether mesic deep-soil habitats on granite outcrops can sustain larger FD than dry shallow-soil habitats.

Methods: We calculated FD for dominant species for five single traits (leaf dry matter content, foliar δ¹³C, foliar C:N ratio, plant height and specific leaf area) and their combinations. We employed Generalized Additive Mixed Models to quantify the relationship between selected climate and soil depth variables, and FD.

Results: More benign (deep-soil) habitats supported larger FD for foliar C:N, plant height and for multiple traits than did shallow-soil habitats.

Conclusions: We suggest that: (1) functional diversification, likely aimed at avoiding intra- and interspecific competition for light and nutrients acquisition, might be the important factor in deep-soil habitats; (2) deep-soils patches on and around granite outcrops may serve as ecological microrefugia for biota associated with resource-rich environments.     

Aminoacylation of tRNA and Protein Turnover in Nitrateand Sulphate-Deficient Spirodela polyrhiza

Cultures of Spirodela polyrhiza were maintained in completeHoagland's medium at 25°C in continuous light. Nitrate-and sulphate-deficient plants were cultured in media containing1/20 Hoagland's nitrate and 1/200 Hoagland's sulphate respectively.After 10 days of growth the plants were examined for total aminoacyltRNA levels. Turnover of leucyl-tRNA and rates of protein synthesiswere assessed by pulse feeding [³H]leucine. Control and nutrient-deficientplants had similar levels of tRNA-associated amino acids. Howeverthe amounts of tRNA, expressed on a fresh weight basis, weresignificantly lower in nitrate- and sulphate-deficient plants.Although the specific radioactivities of leucyltRNA were highestin deficient cultures the rate of turnover of this pool wasless than non-deficient control or nitrate- and sulphate-supplementedplants. Calculation of the average rate constants for proteinsynthesis and degradation showed that nitrate deficiency, althoughnot affecting rates of synthesis, supported rates of proteindegradation that were higher than control cultures. ¹ Present address: The Biological Laboratories, Harvard University,16 Divinity Avenue, Cambridge, Massachusetts 02138, U.S.A. (Received March 7, 1983; Accepted August 16, 1983)     

Attempt at demonstrating the effect of a weak magnetic field onTaraxacum officinale

The exposure ofTaraxacum officinale L. at flowering time to a weak magnetic field resulted in (1) retarded opening and the closing of the inflorescence, (2) wilting and death after prolonged exposure. Controls were unchanged. Plants exposed to the effect of magnetic fields were degenerated in subsequent year.     

International Code of Phytosociological Nomenclature. 4th edition

The fourth edition of the International Code of Phytosociological Nomenclature (ICPN) was prepared by the Steering Committee of the IAVS Working Group for Phytosociological Nomenclature (GPN). The edition consists of 14 Definitions, 7 Principles, 53 Articles, and 7 Appendices. When compared with the previous edition, the main amendments are: (a) the acceptance of electronic publications (Art. 1); (b) the introduction of binding decisions (Definition XIV, Principle II, Articles 1, 2b, 3c, 29b, 40, 42, 44, Appendices 6 and 7); (c) the mandatory use of the English or Latin terminology for syntaxonomic novelties (Definition II, Principle II, Articles 3d and 3i); (d) the introduction of autonyms for the main ranks when the corresponding secondary ranks are created (Articles 13b and 24); (e) the automatic correction of the taxon names (name-giving taxa) used in the names of syntaxa in accordance with the International Code of Nomenclature for algae, fungi, and plants (ICN) (Article 44); (f) the possibility to mutate the name of a syntaxon in using other correct, alternative names for the name-giving taxa (Article 45); (g) the introduction of inadequate names, a new category of rejected names (Definition V, Articles 43 through 45); and (h) the introduction of a conserved type (Definition XIII, Article 53). The fourth edition of ICPN was approved by the GPN on 25 May 2019 and becomes effectively binding on 1 January 2021.     

Testicular toxicity of cyanobacterial biomass in Japanese quails

Previous studies demonstrated the toxic effects of cyanobacteria in Japanese quails (Coturnix coturnix japonica) in various experimental set-ups including acute, sub-chronic and reproduction toxicity, co-exposures with toxic metals and the Newcastle vaccination. This study aimed to assess the testicular toxicity of a complex cyanobacterial biomass administered to Japanese quails in the feed for eight weeks (daily dose of 61.62 μg microcystins pro toto including 26.54 μg MC-RR, 7.62 μg MC-YR and 27.39 μg MC-LR). There was no mortality in the controls or the biomass-exposed birds. However, males exposed to cyanobacteria in the feed showed moderate to marked atrophy of the seminiferous tubular epithelium with only sparse numbers of the developmental stages of spermatozoa and Sertoli cells. Biomass-exposed birds had elevated catalase activities but decreased glutathione peroxidase activities and surprisingly lower levels of lipid peroxides in the testes. The other biochemical parameters studied (i.e., glutathione level and glutathione reductase, glutathione-S-transferase and superoxide dismutase activities) showed no differences. The cell defensive system protecting testicular tissue from the damage associated with toxic effects of the complex cyanobacterial biomass seemed to be insufficient and partly depleted after the chronic exposure of male birds to this biomass.     

Glycosphingolipid profile of the apical pole of human placental capillaries: the relevancy of the observed data to Fabry disease

A series of six full-term placentas and umbilical cords were examined using the in situ detection of globotriaosylceramide (Gb3Cer), GM1 ganglioside (GM1), GM3 ganglioside (GM3), cholesterol and caveolin 1. Immunohistochemical study showed uniform distinct staining of the apical membrane of villous capillary endothelial cells for Gb3Cer, GM1, GM3 and cholesterol. There was also a strong signal for caveolin 1. The immunophenotype suggests the presence of caveola-associated raft microdomains. The immunophenotype was almost completely shared with the extravillous intravascular trophoblast in the basal plate. It was absent in the endothelial cells of umbilical vessels and in the capillaries of somatic structures (heart, lung, skeletal muscle and skin) in neonates as well as in adults, including capillaries of the proliferative endometrium. Results of in situ analyses were confirmed by lipid chromatographic analysis of tissue homogenates and by tandem mass spectrometry. Lysosomal Gb3Cer turnover was followed in three placentas including umbilical cords from Fabry disease (α-galactosidase A deficiency). Lysosomal storage was restricted to vascular smooth muscle cells and to endothelial cells of umbilical vessels. Placental villous capillary endothelial cells displaying a strong non-lysosomal staining for Gb3Cer were free of lysosomal storage.     

Synthesis and cytotoxic activities of estrone and estradiol cis-dichloroplatinum(II) complexes

Sixteen platinum(II) complexes of estrone and estradiol were synthesized in this work to evaluate their cytotoxic activity against several cancer cell lines including estrogen dependent and independent ones. The synthesis of all the complexes was done in three steps. The reaction of steroids with dibromoalkanes was followed by a reaction of the bromoalkyl steroids with 2-(aminomethyl)pyridine or 2-(2-aminoethyl)pyridine. The last step was a reaction of steroidal diamino ligands with potassium tetrachloroplatinate to obtain the desired platinum(II) complexes. Cytotoxicity assays showed that most of the complexes prepared are active against the cancer cell lines used—CEM, U-2 OS, MCF7, MCF7 AL, MDA-MB-468, BT-474, BT-549, and BJ fibroblasts. The six-membered platinum complexes are more active than five-membered ones.