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Common Characters (common + character)

Distribution by Scientific Domains

Life Sciences	60%
Earth and Environmental Science	40%

Selected Abstracts

The status of warning services for plant pests in Italy,

EPPO BULLETIN, Issue 1 2000
V. Rossi
A survey of the present status of warning services for plant protection in Italy shows the lack of a national project, so that the different regional governments approach the question in different ways. In spite of this, some common characters are present: (1) most of the regions manage the warning service directly; (2) everywhere, the warning service interacts with research institutes, farmers' associations, agrometeorological networks and other warning services; (3),indirect warning' is the prevalent model of organization; geographical areas are divided into homogeneous subareas, where information useful for producing advice is collected and elaborated; warnings are then disseminated by different means of communication, and farmers comply with them autonomously; (4) warnings are usually prepared by a team of advisers, who meet periodically, analyse available information and elaborate suggestions for crop protection; (5) available information comes from field monitoring, weather stations, insect and spore traps, forecasting models for pests and diseases; unfortunately, forecasting models are not widespread; (6) the content of warnings is rather uniform, including information on crops pests and diseases, suggestions for control strategies and, frequently, meteorological conditions and forecasts; (7) different means are used to disseminate warnings to farmers; usually several methods co-exist: bulletins published in local newspapers, sent by mail or fax, displayed on notice boards or available via the Internet; placards; telephone messages; surveys on local TV or radio. [source]

Muscle fibre types and size distribution in sub-antarctic notothenioid fishes

JOURNAL OF FISH BIOLOGY, Issue 6 2000
D. A. Fernandez
The presumptive tonic muscles fibres of Cottoperca gobio, Champsocephalus esox, Harpagifer bispinis, Eleginops maclovinus, Patagontothen tessellata, P. cornucola and Paranotothenia magellanica stained weakly or were unstained for glycogen, lipid, succinic dehydrogenase (SDHase) and myosin ATPase (mATPase) activity. Slow, intermediate and fast twitch muscle fibres, distinguished on the basis of the pH stability of their mATPases, showed intense, moderate and low staining activity for SDHase, respectively. Slow fibres were the major component of the pectoral fin adductor profundis muscle. The proportion of different muscle fibre types varied from the proximal to distal end of the muscle, but showed relatively little variation between species. The myotomes contained a lateral superficial strip of red muscle composed of presumptive tonic, slow twitch and intermediate fibres, thickening to a major wedge at the horizontal septum. All species also had characteristic secondary dorsal and ventral wedges of red muscle. The relative abundance and localization of muscle fibre types in the red muscle varied between species and with body size in the protandric hermaphrodite E. maclovinus. The frequency distribution of diameters for fast twitch muscle fibres, the major component of deep white muscle, was determined in fish of a range of body sizes. The absence of fibres <20 ,m diameter was used as a criterion for the cessation of muscle fibre recruitment. Fibre recruitment had stopped in P. tessellata of 13·8 cm LT and E. maclovinus of 32·8 cm LT, equivalent to 49 and 36·5% of their recorded maximum sizes respectively. As a result in 20-cm P. tessellata, the maximum fibre diameter was 300 ,m and 36% of fibres were in excess of 200 ,m. The unusually large maximum fibre diameter, the general arrangement of the red muscle layer and the extreme pH lability of the mATPase of fast twitch fibres are all common characters of the sub-Antarctic and Antarctic Notothenioids, including Cottoperca gobio, the suggested sister group to the Notothenidae. [source]

A key and four new species of Hedysarum (Fabaceae) in Iran

NORDIC JOURNAL OF BOTANY, Issue 1-2 2008
M. Ranjbar
A key, descriptions and new findings are given for some species from of the short-stemmed group Hedysarum sect. Multicaulia, which occur within the area covered by the flora of the north-eastern part of Iran (Khorassan Province). They have short stem, becoming woody at base, standard as long as keel and pods, glabrous or densely covered with grey appressed hairs. In addition, H.longepedunculatum, H. bojnordense, H. paucifoliolatum and H. glabrifoliolatum are described and illustrated as new species. The relationships between the new species and their closest relatives are discussed. Hedysarum fallacinum Rech. f. & Aellen is reduced to a synonym of H. kopetdaghi Boriss. on the basis of their common characters such as arrangement of branches and flowers, shape of leaflet and size of calyx and corolla. [source]

Silicified Upper Ordovician trilobites from Pai-Khoi, Arctic Russia

PALAEONTOLOGY, Issue 6 2009
ROBERT M. OWENS
Abstract:, A collection of silicified trilobites extracted from samples obtained by F. Nansen from the Upper Ordovician of Khabarovo, Pai Khoi, Russian Arctic is dominated by two new species of the proetide Lasarchopyge, a genus known hitherto only from the Argentine Precordillera. Comparison of Lasarchopyge with Scharyia reveals a range of common characters that support inclusion of both genera in the same family. The rest of the fauna comprises a metagnostid (Trinodus elspethi), an asaphid (Isotelus sp.), two remopleuridids (Remopleurides cf. caelatus and R. sp. nov. A), an aulacopleurid (Harpidella triloba), a lichid and an odontopleurid (Apianurus cf. barbatus), the last two being represented by very fragmentary material. T. elspethi, H. triloba, R. cf. caelatus and A. cf. barbatus are common to or closely resemble taxa from the Edinburg Formation, Virginia. Closely related taxa are present also in the Esbataottine Formation, NW Territories, Canada, and in the Albany Group, Girvan district, Scotland. All of these occurrences are of early Caradoc (Sandbian) age, and most lay at palaeolatitudes of 20°,30° south; all are interpreted as having been deposited on the outer shelf, which is consistent with their distribution. [source]

Establishment of Liebermannia dichroplusae n. comb. on the Basis of Molecular Characterization of Perezia dichroplusae Lange, 1987 (Microsporidia)

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 3 2007
YULIYA Y. SOKOLOVA
ABSTRACT. Perezia dichroplusae Lange, 1987 is a parasite of the Malpighian tubules of an Argentine grasshopper, Dichroplus elongatus (Orthoptera, Acrididae, Melanoplinae). In order to determine relationships of this microsporidium with Perezia nelsoni and with other microsporidia, we sequenced its small subunit ribosomal RNA gene (SSU rDNA) (GenBank Accession No. EF016249) and performed phylogenetic analysis of the novel sequence against 17 microsporidian SSU rDNA sequences from GenBank, using neighbor-joining (NJ), maximum-parsimony (MP), and maximum-likelihood (ML) methods. This analysis revealed the highest similarity (96%) of the new sequence to Liebermannia patagonica, a parasite of gut epithelium cells of another grasshopper from Argentina, versus only 65% similarity to P. nelsoni, a parasite of muscles of paenaeid shrimps. In phylogenetic trees inferred from SSU rDNA sequences, the microsporidium from D. elongatus is sister taxon to L. patagonica and both cluster with Orthosomella operophterae. At the higher hierarchical level, the Liebermania,Orthosomella branch forms a clade with the Endoreticulatus,Cystosporogenus,Vittaforma group and with Enterocytozoon bieneusi. Perezia nelsoni falls into another large clade together with Nosema and Ameson species. We propose transferring P. dichroplusae to the genus Liebermannia and creating a new combination Liebermannia dichroplusae n. comb., based both on SSU rDNA sequence analysis and on common characters between P. dichroplusae and L. patagonica, which include the presence of elongated multinuclear sporonts, sporoblastogenesis by a similar process of sequentially splitting off sporoblasts, ovocylindrical spores of variable size, tissue tropism limited to epithelial cells, Orthoptera as hosts, and geographical distribution of hosts in the southern temperate region of Argentina. We argue that the condition of the nuclei in spores (i.e. diplokaryotic in L. patagonica or monokaryotic in L. dichroplusae) cannot be used to distinguish genera. Therefore, we remove the statement about the presence of diplokaryotic spores from the revised diagnosis of the genus Liebermannia. [source]