Krogia coralloides, a new lichen genus and species from Mauritius

2002 ◽  
Vol 34 (4) ◽  
pp. 293-296 ◽  
Author(s):  
Einar Timdal
Keyword(s):  
Related Compound ◽  
Humid Forest ◽  
Thallus Anatomy

AbstractThe new corticolous lichen genus Krogia and species K. coralloidesare described from humid forest in Mauritius. The genus shows affinities with Phyllopsora, but differs in characters of the ascus, ascospores, and thallus anatomy. The ascal characters make its inclusion in the Bacidiaceae or Phyllopsoraceae problematic. The lichen contains boninic acid and an apparently related compound.

scholarly journals Reaction between sheep liver mitochondrial aldehyde dehydrogenase and various thiol-modifying reagents

1989 ◽  
Vol 261 (1) ◽  
pp. 281-284 ◽  
Author(s):  
K M Loomes ◽  
T M Kitson
Keyword(s):  
Aldehyde Dehydrogenase ◽  
Related Compound ◽  
Physiological Responses ◽  
Enzymic Activity ◽  
Cysteine Residues ◽  
Mitochondrial Enzyme ◽  
Step Process ◽  
Cytoplasmic Enzyme ◽  
Sheep Liver

Sheep liver mitochondrial aldehyde dehydrogenase reacts with 2,2′-dithiodipyridine and 4,4′-dithiodipyridine in a two-step process: an initial rapid labelling reaction is followed by slow displacement of the thiopyridone moiety. With the 4,4′-isomer the first step results in an activated form of the enzyme, which then loses activity simultaneously with loss of the label (as has been shown to occur with the cytoplasmic enzyme). With 2,2′-dithiodipyridine, however, neither of the two steps of the reaction has any effect on the enzymic activity, showing that the mitochondrial enzyme possesses two cysteine residues that must be more accessible or reactive (to this reagent at least) than the postulated catalytically essential residue. The symmetrical reagent 5,5′-dithiobis-(1-methyltetrazole) activates mitochondrial aldehyde dehydrogenase approximately 4-fold, whereas the smaller related compound methyl l-methyltetrazol-5-yl disulphide is a potent inactivator. These results support the involvement of mixed methyl disulphides in causing unpleasant physiological responses to ethanol after the ingestion of certain antibiotics.

The synthesis and characterization of the superconductor-related compound Pb2Sr2AmCu3O8

1996 ◽  
Vol 101 (4) ◽  
pp. 539-545 ◽  
Author(s):  
L. Soderholm ◽  
Clayton Williams ◽  
S. Skanthakumar ◽  
Mark R. Antonio ◽  
S. Conradson
Keyword(s):  
Related Compound ◽  
Synthesis And Characterization

An evaluation of ECOSTRESS products of a temperate montane humid forest in a complex terrain environment

2021 ◽  
Vol 265 ◽  
pp. 112662
Author(s):  
Ning Liu ◽  
A. Christopher Oishi ◽  
Chelcy Ford Miniat ◽  
Paul Bolstad
Keyword(s):  
Complex Terrain ◽  
Humid Forest

scholarly journals Phytogeographical patterns of dry forests sensu stricto in northern Minas Gerais State, Brazil

2013 ◽  
Vol 85 (2) ◽  
pp. 623-634 ◽  
Author(s):  
DANIEL M. ARRUDA ◽  
WALNIR G. FERREIRA-JUNIOR ◽  
REINALDO DUQUE-BRASIL ◽  
CARLOS E.R. SCHAEFER
Keyword(s):  
Late Quaternary ◽  
Sensu Stricto ◽  
Minas Gerais ◽  
Dry Forest ◽  
Floristic Similarity ◽  
Humid Forest ◽  
Quaternary Climate ◽  
Dominant Soil ◽  
Minas Gerais State ◽  
Semi Arid

The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.

Revision of Pycnandra subgenus Achradotypus (Sapotaceae), with five new species from New Caledonia

2010 ◽  
Vol 23 (3) ◽  
pp. 185 ◽  
Author(s):  
Ulf Swenson ◽  
Jérôme Munzinger
Keyword(s):  
New Caledonia ◽  
Iucn Red List ◽  
Red List ◽  
Corolla Lobe ◽  
Vegetation Types ◽  
New Members ◽  
Infrageneric Classification ◽  
Humid Forest ◽  
Leaf Venation ◽  
Wide Range

Pycnandra is a genus of Sapotaceae (Chrysophylloideae), restricted to New Caledonia, and includes ~60 species. The genus is a member of the monophyletic Niemeyera complex of Australia and New Caledonia and it is characterised by the lack of staminodes and a fruit containing a single seed, plano-convex cotyledons and absence of endosperm. In New Caledonia, several segregate genera have been recognised, but weak cladistic support for these groups and homoplasious morphology renders a narrow generic concept untenable. Instead, a broad generic circumscription of Pycnandra with an infrageneric classification recognising the subgenera Achradotypus, Leptostylis, Pycnandra, Sebertia and Trouettia results in a stable nomenclature. Here we revise Pycnandra subg. Achradotypus that includes 14 species, of which five (P. belepensis, P. blaffartii, P. bracteolata, P. glabella, and P. ouaiemensis) are described as new. Members of subg. Achradotypus are distinguished from other subgenera on the basis of a character combination of two stamens opposite each corolla lobe (except P. litseiflora), glabrous leaves (except P. belepensis and P. decandra), a distinctive reticulate tertiary leaf venation (except P. comptonii), and sepal-like bracts that often are borne along the pedicel. All species are restricted to Grande Terre except for P. decandra, whose distribution also extends to nearby Art Island (Belep Islands), and P. belepensis, which is endemic to that same island. The members grow in a wide range of vegetation types from dry maquis to humid forest, from sea level to the highest mountain massif, and on ultramafic soils to schist and greywacke (not limestone). Because of past and present threats such as mining, logging and fire, preliminary IUCN Red List assessments are provided for all species. Five taxa (P. chartacea, P. decandra subsp. decandra, P. glabella, P. litseiflora, and P. neocaledonica) are proposed the IUCN status Endangered, and P. belepensis and P. ouaiemensis are proposed to be Critically Endangered. We suggest that some locations where these species occur should be given protection in the form of nature reserves.

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