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1.
Post-Viking Microbiology: New Approaches,New Data,New Insights   总被引:1,自引:0,他引:1  
In the 20 years since the Viking experiments, major advances have been made in the areas of microbial systematics, microbial metabolism, microbial survival capacity, and the definition of environments on earth, suggesting that life is more versatile and tenacious than was previously appreciated. Almost all niches on earth which have available energy, and which are compatible with the chemistry of carbon-carbon bonds, are known to be inhabited by bacteria. The oldest known bacteria on earth apparently evolved soon after the formation of the planet, and are heat loving, hydrogen and/or sulfur metabolizing forms. Among the two microbial domains (kingdoms) is a great deal of metabolic diversity, with members of these forms being able to grow on almost any known energy source, organic or inorganic, and to utilize an impressive array of electron acceptors for anaerobic respiration. Both hydrothermal environments and the deep subsurface environments have been shown to support large populations of bacteria, growing on energy supplied by geothermal energy, thus isolating these ecosystems from the rest of the global biogeochemical cycles. This knowledge, coupled with new insights into the history of the solar system, allow one to speculate on possible evolution and survival of life forms on Mars.  相似文献   

2.
何汉兴 《菌物学报》2013,32(Z1):20-44
综述了中国大陆腐霉属的研究进展,内容包括腐霉属菌物的发生、分布、分类鉴定、致病性、所致植物病害防治及腐霉的利用等方面.至今,中国已报道的腐霉属菌物有64个种,其中有13个种作为世界新种进行了描述,这13个新种分别为:顶生腐霉Pythium acrogynum,孤雌腐霉P.amasculinum,百色腐霉P.baisense,北方腐霉P.boreale,短枝腐霉P.breve,壁合腐霉P.connatum,镰雄腐霉P.falciforme,贵阳腐霉P.guiyangense,广西腐霉P.guangxiense,下雄腐霉P.hypoandrum,昆明腐霉P.kummingense,南宁腐霉尸nanningense和中国腐霉P.sinensis.瓜果腐霉Pythium aphanidermatum为优势种,在全国普遍引起多种植物严重的猝倒病和根、茎、叶、果腐烂病.其中,大多数腐霉种对植物具有致病性,44个种寄生植物,1个种:紫菜腐霉P.porphyrae寄生红藻和紫菜,2个种:卡地腐霉P.carolinianum 和贵阳腐霉P.guiyangense寄生蚊子幼虫,2个种:努氏腐霉P.nunn和寡雄腐霉P.oligandrum 是真菌的重寄生菌.相比之下,台湾报道的腐霉种有48种(其中新种1个:四季腐霉P.sukuiense),海南报道的腐霉种有28种.对中国大陆腐霉属的研究前景也进行了讨论.  相似文献   

3.
Russian Journal of Bioorganic Chemistry - Nucleic acids have made a long and arduous journey “from the bench to the bedside.” At present, it can be assumed that drugs based on...  相似文献   

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《Anthrozo?s》2013,26(1):3-4
Abstract

Published eyewitness accounts and stories from Aboriginal Australians are used to provide an overview of the geographical extent and characteristics of cooperative fishing between Aboriginal Australians and dolphins in eastern Australia. These sources indicate that cooperative fishing was geographically widespread in eastern Australia, involved both bottlenose dolphins and orcas, and had a significance (emotional and spiritual) to Aboriginal people beyond the acquisition of food. These fishing interactions represent both context and precedent for the economic and emotional objectives of contemporary human–dolphin interactions such as dolphin provisioning.  相似文献   

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中国蝴蝶新种、新亚种及新记录种(VI)   总被引:13,自引:0,他引:13  
记述蛱蝶科12新种,2新亚种,1新型,6新记录,4个在《中国蝶类志》中未记载的已知种。所有模式标本均保存在西北农林科技大学昆虫博物馆。  相似文献   

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Abstract

The new gammarideans Photis nigrocula, P. phaeocula, and Halice sublittoralis are described from grab samples taken from the North Arm of Port Pegasus, where they appear to be the most abundant amphipods on the sandy-mud substrate. They are illustrated and compared with closely related taxa.  相似文献   

10.
New data, please     
Meetings and conferences are the best places to feature the latest results coming out of the laboratory. Unfortunately, not enough researchers take advantage of these opportunities.  相似文献   

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Dineutus assimilis Kirby and Dineutus discolor Aubé of the Family Gyrinidae are newly reported from New Brunswick, Canada. Four species of Carabidae, Agonum (Agonum) piceolum (LeConte), Bembidion (Pseudoperyphus) rufotinctum Chaudoir, Harpalus (Harpalus) opacipennis (Haldeman), and Pterostichus (Melanius) castor Goulet & Bousquet are newly reported from New Brunswick and the Maritime provinces, and one species of Dytiscidae, Liodessus noviaffinis Miller, is newly recorded for the province. Collection, habitat data, and distribution maps are presented for each species.  相似文献   

14.
We report 21 new species records for the Coleoptera fauna of New Brunswick, Canada, seven of which are new records for the Maritime provinces. Four species of Mycetophagidae (Litargus didesmus Say, Litargus tetrapilotus LeConte, Mycetophagus punctatus Say, and Mycetophagus quadriguttatus Müller) are newly reported for the province of New Brunswick. Litargus didesmus is newly recorded for the Maritime provinces. Seven species of Tetratomidae are added to the faunal list of New Brunswick: Eustrophus tomentosus Say, Penthe obliquata (Fabricius), and Tetratoma tessellata Melsheimer are new to New Brunswick: Hallomenus serricornis LeConte, Pisenus humeralis Kirby, Synstrophus repandus (Horn), and Tetratoma variegata Casey, which are newly recorded for New Brunswick and the Maritime provinces. Ten additional species of Melandryidae are reported from New Brunswick, of which Orchesia cultriformis Laliberté, Orchesia ovata Laliberté, Phloeotrya fusca (LeConte), Scotochroides antennatus Mank, Spilotus quadripustulatus (Melsheimer), Symphora flavicollis (Haldeman), Symphora rugosa (Haldeman), and Zilora hispida LeConte are new for the province, and Microscapha clavicornis LeConte and Zilora nuda Provancher are newly recorded for the Maritime provinces. In addition, we report numerous additional records for three species of Mycetophagidae and one species of Melandryidae previously recorded from New Brunswick that suggest these species are more widely distributed than previously known. Collection, habitat data, and distribution maps are presented for all these species.  相似文献   

15.
We report ten new species records for the Coleoptera fauna of New Brunswick, Canada from the families Dermestidae, Endecatomidae, Bostrichidae, and Ptinidae. Anthrenus fuscus Olivier and Anthrenus museorum (Linnaeus) of the family Dermestidae are newly recorded for New Brunswick. Endecatomus rugosus (Randall) and the family Endecatomidae are recorded for the first time for New Brunswick and the Maritime provinces. Two Bostrichidae, the adventive Dinoderus minutus (Fabricius) and the native Stephanopachys substriatus (Paykull), are newly recorded for the province. Five species of Ptinidae, the adventive Anobium punctatum (DeGeer) and Microbregma emarginatum emarginatum (Duftschmid), and the native Hadrobregmus notatus (Say), Ptilinus lobatus Casey, and Ptilinus ruficornis Say are added to the faunal list of New Brunswick. Collection data, habitat data, and distribution maps are presented for all these species.  相似文献   

16.
Two species of Sphindidae, Odontosphindus denticollis LeConteand Sphindus trinifer Casey, are reported for the first time for New Brunswick. Another species, Sphindus near americanus LeConte is reported from the province but may be an undescribed species, pending further study. Five species of Erotylidae are newly recorded for the province, including Tritoma humeralis Fabricius and Tritoma sanguinipennis (Say), which are new to the Maritime provinces. Three species of Monotomidae are added to the New Brunswick faunal list, including Pycnotomina cavicollis (Horn), which is newly recorded for the Maritime provinces. Six additional species of Cryptophagidae are reported for the province and the presence of Antherophagus convexulus LeContein New Brunswick is confirmed. Cryptophagus pilosus Gyllenhal and Myrmedophila americana (LeConte) are newly reported to the Maritime provinces.  相似文献   

17.
We report five new species records for New Brunswick, Canada from the Coleoptera families Dryopidae, Elimidae, Psephenidae, and Ptilodactylidae. Dryops viennensis (Heer) (Dryopidae) and Promoresia elegans (LeConte) (Elmidae) are added to the faunal list for New Brunswick and the Maritime provinces. Two Psephenidae species, Ectopria nervosa (Melsheimer) and Ectopria thoracica (Ziegler) are reported for the first time for New Brunswick, and the latter species is also new for the Maritime provinces. Anchytarsus bicolor (Melsheimer) and the family Ptilodactylidae are newly recorded for New Brunswick and the Maritime provinces. Collection, habitat data, and distribution maps are presented for all of these species.  相似文献   

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Five sources of data force extensive revision of ideas about the nature and evolution of monocot xylem: scanning electron microscopy (SEM) studies of thick sections; availability of molecular phylogenies covering a relatively large number of families and genera; information on ecology and habitat; data concerning habit; and observations from xylem physiology. These five new sources of data, absent from the studies of Cheadle, plus added information from light microscopy, lead to a fresh understanding of how xylem has evolved in monocots. Tracheary elements hitherto recorded as vessel elements with scalariform end walls prove in a number of instances, to retain pit membranes (often porous or reticulate) in the end walls. There is not an inexorable progression from "primitive" to "specialized" xylem in monocots; apparent accelerations or reversions are also possible. The latter include such changes as the result of production of narrower vessel elements; or production of less metaxylem, which is probably heterochronic in nature (an extreme form of juvenilism). Tracheary elements intermediate between vessel elements and tracheids must be recognized for what they are, and not forced into mutually exclusive categories. Original data on tracheids and various types of vessel elements is related here to ecology and habit of groups such as Asteliaceae, Boryaceae, Cyclanthaceae, Orchidaceae, Pandanaceae, Taccaceae, Typhaceae, dracaenoid Asparagaceae, and Zingiberales. Data from palm xylem shows a nearly unique syndrome of features that can be explained with the aid of information from physiology and ecology. Vessellessness of stems and leaves characterizes a large number of monocot species; the physiological and ecological significance of these is highlighted. An understanding of how non-palm arborescent monocots combine an all-tracheid stem xylem with addition of bundles and vegetative modifications is attempted. The effect of the disjunction between xylems of adventitious roots and stems, providing a physiologically demonstrated valve ("rectifier") effect is discussed. "Ecological iteration" has occurred in some monocot lineages, so that early-departing branches in some cases may have more "specialized" xylem because of entry into xeric habitats, whereas nearby crown groups, which may have retained "primitive" xylem, probably represent long occupation of mesic habitats. Cheadle's use of xylem for "negations" of phyletic pathways can no longer be accepted. Symplesiomorphic mesomorphic xylem patterns do characterize many of the earlier-departing branches in the monocots as a whole, however. Cheadle's idea that monocots and non-monocot angiosperms attained vessels independently is improbable in the light of molecular trees for angiosperms. Vessels in roots seem an adaptation to major swings in moisture availability to adventitious roots as compared to taproots. The commonness of all-tracheid plans in stems and leaves in earlier-departing monocot clades is a feature that requires further clarification but is primarily related to the xylem disjunction that adventitious roots have. Secondary vessellessness or something very close to it can be hypothesized for Campynemataceae, Philesiaceae, Taccaceae, and some Orchidaceae. Eleven salient shifts in our conceptual views of monocot xylem are proposed and conclude the paper. Monocot xylem is not a collection of historical information, but a rigorously parsimonious system related to contemporary habits and habitats.  相似文献   

20.
We report 20 new species records for the Coleoptera fauna in New Brunswick, Canada, five of which are new records for the Maritime provinces, including one species that is new for Canada. One species of Kateretidae, Kateretes pusillus (Thunberg) is newly recorded for New Brunswick and the Maritime provinces. Stelidota octomaculata (Say), Phenolia grossa (Fabricius), andCryptarcha strigatula Parsons of the family Nitidulidae are added to the faunal list of New Brunswick; the latter species is new to the Maritime provinces. Two species of Cerylonidae, Philothermus glabriculus LeConte and Cerylon unicolor (Ziegler), are reported for the first time for New Brunswick. Philothermus glabriculus is new for the Maritime provinces. Two species of Endomychidae, Hadromychus chandleri Bousquet and Leschen and Danae testacea (Ziegler) are newly recorded for New Brunswick. Three species of Coccinelidae, Stethorus punctum punctum (LeConte), Naemia seriata seriata Melsheimer, and Macronaemia episcopalis (Kirby) are added to the provincial list. Macronaemia episcopalis (Kirby) is a species new to the Maritime provinces. Nine species of Latridiidae, Cartodere nodifer (Westwood), Dienerella ruficollis (Marsham), Enicmus aterrimus Motschulsky, Enicmus fictus Fall, Encimus histrio Jay and Tomlin, Lathridius minutus (Linnaeus), Stephostethus productus Rosenhauer, Corticaria elongata (Gyllenhal), and Corticarina longipennis (LeConte) are newly recorded for New Brunswick. Stephostehus productus is newly recorded from Canada. Collection and habitat data are presented for all these species.  相似文献   

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