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N O Santos - One of the best experts on this subject based on the ideXlab platform.
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kerr geodesics the penrose process and jet collimation by a black hole
Astronomy and Astrophysics, 2010Co-Authors: J Gariel, Malcolm Maccallum, G Marcilhacy, N O SantosAbstract:Aims. We re-examine the possibility that astrophysical jet collimation may arise from the geometry of rotating black holes and the presence of high-energy particles resulting from a Penrose process, without the help of magnetic fields. Methods. Our analysis uses the Weyl coordinates, which are revealed better adapted to the desired shape of the jets. We numerically integrate the 2D-geodesics equations. Results. We give a detailed study of these geodesics and give several numerical examples. Among them are a set of perfectly collimated geodesics with asymptotes ρ = ρ1 parallel to the z-axis, with ρ1 only depending on the ratios Q E2−1 and a M ,w herea and M are the parameters of the Kerr black hole, E the particle energy and Q the Carter’s constant.
Vlada Peneva - One of the best experts on this subject based on the ideXlab platform.
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Ground beetles (Coleoptera: Carabidae) diversity from harvested oilseed rape fields (Brassica napus L.) in Southern Bulgaria
ARPHA Conference Abstracts, 2019Co-Authors: Teodora Teofilova, Ivailo Todorov, Milka Elshishka, Vlada PenevaAbstract:This study aimed at clarifying the species composition and ecological structure of carabid communities, in oilseed rape fields after rape harvest. Field work was carried out in 2018. Pitfall traps (5 in each site) were set in 10 sampling sites in Thracean Lowland and Sarnena Sredna Gora Mts. Captured beetles belonged to 66 species and 24 genera, representing 9% of the species and 19% of the ground beetle genera occurring in Bulgaria. The most diverse was genus Harpalus Latreille, 1802 (15 species), followed by the genera Amara Zimmermann, 1832 (7 species), Microlestes Schmidt-Goebel, 1846 (6 species) and Parophonus Ganglbauer, 1891 (5 species). Five species were new for the region of the Thracean Lowland: Amara (Bradytus) consularis (Duftschmid, 1812), Harpalus (Harpalus) caspius (Steven, 1806), H. (Pseudoophonus) calceatus (Duftschmid, 1812), Microlestes negrita negrita (Wollaston, 1854), Tachyura (Tachyura) parvula (Dejean, 1831). Three species: Amara (Zezea) fulvipes (Audinet-Serville, 1821), A. (Zezea) chaudoiri incognita Fassati, 1946 and Diachromus germanus (Linnaeus, 1758) were new records for the region of the Sarnena Gora. Seven species were new for the whole Sredna Gora Mts.: Acinopus (Acinopus) picipes (Olivier, 1795), A. (Oedematicus) megacephalus (P. Rossi, 1794), Carterus (Carterus) dama (P. Rossi, 1792), Harpalus (Harpalus) flavicornis flavicornis Dejean, 1829, H. (Pseudoophonus) griseus (Panzer, 1796), Licinus (Licinus) depressus (Paykull, 1790) and Microlestes maurus maurus (Sturm, 1827). Genera Acinopus Dejean, 1821, Carterus Dejean, 1830 and Licinus Latreille, 1802 were new geographic records for the Sredna Gora Mts. Twelve life form categories were established (7 zoophagous and 6 mixophytophagous). The analysis of the life forms showed a slight predominance of the mixophytophages (38 species; 58%) over the zoophages (28 species; 42%). There were no constant species occurring in all sampling sites (with 100% occurrence). Thirteen species appeared after the harvest (they were absent during the flowering and ripening of the rape), forty-four species disappeared (they were present during flowering and ripening), and twenty-nine species were present in all stages.
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Ground beetles (Coleoptera: Carabidae) diversity from pastures in Southern Bulgaria
ARPHA Conference Abstracts, 2019Co-Authors: Teodora Teofilova, Ivailo Todorov, Milka Elshishka, Vlada PenevaAbstract:This study aimed at clarifying the species composition and ecological structure of carabids, associated with active pastures. Field work was carried out in 2017 and 2018. Pitfall traps (5 in each site) were set in 10 sampling sites in Thracean Lowland and Sarnena Sredna Gora Mts. Captured beetles belonged to 90 species and 33 genera, representing 12% of the species and 26% of the ground beetle genera occurring in Bulgaria. The most diverse was genus Harpalus (22 species), followed by the genera Amara (7 species), Microlestes (6 species), Ophonus (6 species) and Parophonus (5 species). Twenty species were new for the region of the Thracean Lowland: Amara fulvipes (Audinet-Serville, 1821), Anisodactylus binotatus (Fabricius, 1787), A. intermedius Dejean, 1829, Apotomus clypeonitens Müller, 1943, Calathus cinctus Motschulsky, 1850, Carterus gilvipes (Piochard de la Brûlerie, 1873), Gynandromorphus etruscus (Quensel en Schönherr, 1806), Harpalus fuscicornis Ménétriés, 1832, H. subcylindricus Dejean, 1829, Microlestes apterus Holdhaus, 1904, M. corticalis (L. Dufour, 1820), M. fulvibasis (Reitter, 1901), M. maurus (Sturm, 1827), M. minutulus (Goeze, 1777), Notiophilus laticollis Chaudoir, 1850, Pangus scaritides (Sturm, 1818), Parophonus laeviceps (Ménétriés, 1832), P. planicollis (Dejean, 1829), Polystichus connexus (Geoffroy in Fourcroy, 1785) and Pterostichus strenuus (Panzer, 1796). Twenty species were new for the whole Sredna Gora Mts.: Acinopus picipes (Olivier, 1795), A. megacephalus (P. Rossi, 1794), Amara anthobia A. Villa et G. B. Villa, 1833, Ditomus calydonius (P. Rossi, 1790), Harpalus albanicus Reitter, 1900, H. angulatus Putzeys, 1878, H. attenuatus Stephens, 1828, H. dimidiatus (P. Rossi, 1790), H. flavicornis Dejean, 1829, H. pumilus Sturm, 1818, H. pygmaeus Dejean, 1829, H. subcylindricus Dejean, 1829, H. tardus (Panzer, 1796), H. signaticornis (Duftschmid, 1812), Lebia scapularis (Geoffroy, 1785), Microlestes fissuralis (Reitter, 1901), M. fulvibasis (Reitter, 1901), M. maurus (Sturm, 1827), M. minutulus (Goeze, 1777) and Ophonus sabulicola (Panzer, 1796). Fourty-one species were new for the region of the Sarnena Sredna Gora. Genus Apotomus, Gynandromorphus, Pangus and Polystichus were new geographic records for Thracean Lowland. Genera Acinopus and Ditomus were new for the Sredna Gora Mts. Fourteen life form categories were established (9 zoophagous and 5 mixophytophagous). The analysis of the life forms showed a slight predominance of the mixophytophages (53 species; 59%) over the zoophages (37 species; 41%). Microlestes minutulus was a constant species occurring in all sampling sites.
José Galián - One of the best experts on this subject based on the ideXlab platform.
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Chromosome evolution in ground beetles: localization of the rDNA loci in the tribe Harpalini (Coleoptera, Carabidae)
Journal of Zoological Systematics and Evolutionary Research, 2004Co-Authors: Elena Maria Martínez‐navarro, José Serrano, José GaliánAbstract:The pattern of localization of the ribosomal genes was studied by means of fluorescence in situ hybridization in 39 species of the tribe Harpalini. Most of them show one pair of autosomes carrying the ribosomal genes in a distal position of a single chromosome arm. This pattern is hypothesized to be ancestral for the whole tribe. Both, chromosome number and the number and localization of rDNA loci, show little variation and are therefore of little phylogenetic value. Only in the subtribe Ditomina is there enough variation to characterize phyletic relationships. The stability of rDNA loci is even higher than the constancy of chromosome number, as most species of Ditomina (genera Dixus, EoCarterus, Carterus, Odontocarus and Ditomus) have the usual pair of autosomes with rDNA loci, in spite of remarkable differences in the diploid number. Only Dixus sphaerocephalus and Dixus clypeatus have two autosomal pairs with a fluorescent signal. These results do not support the hypothesis that the high chromosome numbers found within Ditomina are the result of polyploid change from the ancestral 2n ¼ 37 karyotype of the tribe Harpalini. Chromosomal translocations or the presence of mobile genetic elements are plausible sources of the few cases of intraspecific polymorphism in the rDNA loci found in species of Harpalus.
David Wrase - One of the best experts on this subject based on the ideXlab platform.
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Revision der Carterus angustus-Gruppe und Bemerkungen zur Gattung Carterus DEJEAN (Col., Carabidae, Harpalini)
1994Co-Authors: David WraseAbstract:By investigation of all types and other material the species belonging to the Carterus angustus group are revised. Described as new: PristoCarterus subg. nov. (type species: C. angustus (MEN.)); C. {Pristocarter us) neglectus spec. nov. Lectotypes are designated for: Ditomus angustus MENETRIES 1832, Odogenius longipennis CHAUDOIR 1846, Ditomus angustipennis CHAUDOIR 1852, Carlerus ignoratus STICHEL 1923, Ditomus cribratus REICHE & SAULCY 1855, Ditomus validiusculus PIOCHARD 1873. New synonyms (with senior synonyms listed first): C. angustus (MEN.) (= longipennis (CHD.) syn. nov.), C. angustipennis ssp. angustipennis (PlOCH.) (= C. ignoratus STICH), C. validiusculus (PlOCH.) (= C. kulzeri SCHAUB.). New status: C. lutshniki ZAMOTAJLOV 1988 (= C. angustipennis ssp. lutshniki ZAMOTAJL). Resto- red status: C. cribratus (REICHE & SAULCY) spec, distinct., no synonym of C. angustus (MEN). A key for the species of PristoCarterus subg. nov. is given, all available distribu- tion datas are named, distribution maps are provided (exept of C. angustus (MEN)). The genus Carterus DEJEAN 1829 is characterized in a new sense, basing on phylogenetic considerations, a phylogenetic system is provided, zoogeograprucal aspects are discussed. The taxa Odontocarus SOLER 1834, Tschitscherinellus CSDG 1906 and Ditomus BONELLI 1810 (= Sabienus DES GOZIS 1882) are to be treated as distinct genera judging from their striking autapomorphies.
B. M. Kataev - One of the best experts on this subject based on the ideXlab platform.
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New data on distribution of ground-beetles of the tribe Harpalini in the Palaearctic, Oriental Region and in Australia (Coleoptera, Carabidae: Harpalini)
Entomological Review, 2015Co-Authors: B. M. KataevAbstract:New data on the distribution of 27 species and subspecies of ground-beetles of the tribe Harpalini in the Palaearctic, Oriental Region and in Australia are provided. The following taxa are reported for the first time: Chydaeus abramovi Kataev et Fedorenko, 2013 from Laos; Anisodactylus poeciloides pseudoaeneus Dejean, 1829 from Mongolia and Tuva (Russia); A. karennius (Bates, 1892) from Bhutan, Vietnam, Laos, the Indian state Assam, and the Chinese province Sichuan; Progonochaetus indicus Kataev, 2002 from Pakistan (Azad Jammu and Kashmir); Pseudorhysopus kabakovi Kataev et Wrase, 2001 from China (Guangxi) and Laos; Dicheirotrichus ( Trichocellus ) obscuricornis (Reitter, 1899) from Georgia; Stenolophus ( Stenolophus ) charis Bates, 1892 from China (Yunnan); S. ( Egadroma ) bajaurae Andrewes, 1924 from Turkmenistan; Hemiaulax dentipennis (Bates, 1892) from Cambodia; Daptus pictus Fischer von Waldheim, 1823 from Afghanistan (Herat and Nimruz); D. komarowi Semenov, 1889 from Egypt; Ophoniscus cribrifrons Bates, 1892 from Vietnam; Harpalus tinctulus luteicornoides Breit, 1913 from Laos and the Chinese provinces Anhui, Jiangxi and Guizhou; H. grilli Kataev, 2002 from Pakistan (Baluchistan); H. parvulus Dejean, 1829 from Australia (New South Wales and South Australia); H. anxioides Kataev, 1991 from Greece (Eastern Macedonia); H. smaragdinus (Duftschmidt, 1812) from Israel; H. uniformis staudingeri Jedlička, 1953 from Iran (Horasan); Ophonus ferrugatus Reitter, 1902 and O. pumilio (Dejean, 1829) from Portugal; O. rufibarbis (Fabricius, 1792) from Afghanistan (Herat); Liochirus cycloderus (Solsky, 1874) from Iran (Horasan) and Afghanistan (Ghor); Oedesis caucasicus (Dejean, 1831) from Uzbekistan; Carterus gilvipes (Piochard de La Brûlerie, 1873) from Ukraine (Odessa Prov.), the Crimea and Krasnodar Territory of Russia; Carterus rufipes (Chaudoir, 1843) from Russia (Daghestan), Azerbaijan and Afghanistan (Nimruz); and Tschitscherinellus oxygonus radjabii (Morvan, 1974) from Afghanistan (Ghazni).