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1.
In the late 1960s, Hong Kong was hit by a wave of social and political unrest, an echo in the colony of China's Cultural Revolution of 1966–69. The unrest spread to parts of Britain's Chinatown, where a leftist movement emerged in sympathy with the Hong Kong agitation. Among the Chinatown leftists were former supporters of the Communist anti-Japanese guerrillas in Hong Kong's rural New Territories. The colonial authorities reacted to these developments in Britain by drawing up plans to protect and assist overseas Hong Kong residents in an attempt to win their political approval and stymie the pro-Communists. The Hong Kong Government Office [HKGO] in London started providing materials for Chinese-language schools and set up various other communal services. Later, it launched a campaign to foster the emigrants’ “Hong Kong identity”. The scheme was in many ways successful. Chinatowners were usually happy to make use of the facilities on offer. However, there is little evidence that the HKGO succeeded in winning their political allegiance.  相似文献   

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The revision of Agrilus (Coleoptera, Buprestidae) pests of citrus trees from A. angulatus species–group comprising six species: A. angulatus (Fabricius, 1798); A. connatus sp. nov.; A. livensKerremans, 1892a, Kerremans, 1892b; A. mediocrisKerremans, 1900; A. nubilusKerremans, 1892a, Kerremans, 1892b and A. olivaceidorsisObenberger, 1917 from South and Southeast Asia is provided. The study is based on examination of all relevant types and 2498 additional specimens. The key to species is given and complemented with illustrations of morphology, habitus, genitalia, size variability, color variability, type specimens and distribution. Comprehensive commented literature references, data on type specimens, faunal records, revised and updated distribution and host plant data are cited for each species. The new species A. connatus sp. nov. from Laos and Thailand is described. The following taxonomic and nomenclatural acts are proposed: the name grisatorKerremans, 1893syn. nov. (Agrilus) is a junior subjective synonym of the name nubilusKerremans, 1892a, Kerremans, 1892b (Agrilus); the name macellusBourgoin, 1922syn. nov. (Agrilus) is a junior subjective synonym of the name olivaceidorsisObenberger, 1917 (Agrilus); the lectotype of Buprestis angulataFabricius, 1798 (now in Agrilus) is designated.www.zoobank.org/urn:lsid:zoobank.org:pub:BAE5BD51-2811-44CE-8BC1-AEEC76075667  相似文献   

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Pinus ponderosa forests occupy numerous topographic and soil complexes across vast areas of the southwestern United States, yet few data exist on species distributions and vegetation–environment relationships for these environmentally diverse landscapes. We measured topography, soils, and vegetation on 66, 0.05-ha plots within a 110,000-ha P. ponderosa landscape in northern Arizona, USA, to discern vegetation–environment relationships on this landscape. We analyzed associations of environmental variables with plant communities and with single-species distributions, and we classified ecological species groups (co-occurring plant species exhibiting similar environmental affinities). Gradients in community composition paralleled gradients in soil texture, available water, organic C, total N, and geographic precipitation patterns. Soil parent material, affected by the presence or absence of volcanic activity, is a primary factor constraining vegetation patterns on this landscape. Using discriminant analysis, we built a model that correctly classified the most important of four grasses (Bouteloua gracilis, Muhlenbergia montana, Sporobolus interruptus, or Festuca arizonica) on 70–80% of plots based on five environmental variables related to soil moisture and resource levels. We also classified 52 of the 271 detected plant species into 18 ecological species groups. Species groups ranged from Phacelia and Bahia groups occupying xeric, volcanic cinder soils low in organic C and total N, to Festuca and Lathyrus groups characterizing moist, loam and silt loam soils. We applied the species groups by estimating P. ponderosa diameter increment in a regression tree using abundances of species groups. The most rapid P. ponderosa diameter growth of 5 mm/year occurred on plots with high importance of the Festuca and Lathyrus groups. Our results on this semi-arid landscape support several general ecological species group principles chiefly developed in temperate regions, and suggest that vegetation–environment research has great potential for enhancing our understanding of P. ponderosa forests occupying vast areas of the southwestern United States.  相似文献   

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Liu J  Wang L  Geng Y  Wang Q  Luo L  Zhong Y 《Genetica》2006,128(1-3):385-394
Lamiophlomis rotata (Lamiaceae), a perennial medicinal herb, is endemic to the Qinghai–Tibet Plateau. A total of 188 individuals from eight natural populations of L. rotata in Qinghai–Tibet Plateau (four from Tibet, two from Yunnan, and two from Qinghai) were analyzed using intersimple sequence repeats (ISSR) and randomly amplified polymorphic DNA (RAPD) techniques. Our results revealed that the level of genetic variation in L. rotata was relatively high (P = 94.85%, I = 0.440 ± 0.220, H T = 0.289 ± 0.028). Three genetic groups corresponding to the three geographic regions were detected, suggesting significant geographic structure. Our results suggest that the highly structured geographic pattern found in L. rotata might represent diverging evolutionary processes associated with the uplifting of the Qinghai–Tibet Plateau and Quaternary climatic oscillations. These findings imply that as many populations as possible should be preserved in situ for the conservation of this species. Given their genetic variability and peripheral distribution, Qinghai and Yunnan populations should be assigned priority for conservation. Optimal harvesting strategies, domestication and tissue culture of L. rotata should be developed as soon as possible to guarantee its sustainable use.  相似文献   

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Gerhard Bauer 《Oecologia》1985,65(3):437-441
Summary The population ecology of Pardia tripunctana and Notocelia roborana, a bud- and a leaf-feeding tortricid respectively, on Rosa spp. was studied.Mortality factors of the egg and larval stages are low and density-independent.Pupal mortality in the soil is a regulatory mechanism: it compensates for density fluctuations, as independent of the initial pupal densities the densities of emerging adults are fairly constant.These mechanisms lead to low density levels, low resource utilization rates, and low density fluctuations. A steady state model is developed to describe the population dynamics.Both species therefore can be considered as equilibrium species.  相似文献   

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Jin H  Tan G  Brar DS  Tang M  Li G  Zhu L  He G 《Plant molecular biology》2006,62(4-5):769-777
The wild species Oryza officinalis Wall. ex Watt (2n = 24, CC) is a valuable genetic resource for rice (O. sativa L., 2n = 24, AA) breeding and genomics research. Genomic in situ hybridization (GISH) and molecular approaches were used to determine the nature and composition of the additional chromosome in a monosomic alien addition line (MAAL) of O. officinalis and its backcross progenies. The extra wild species chromosome in the MAAL (2n = 2x = 25) was a mosaic one, comprising of the long arm of chromosome 4 from O. officinalis and the short arm from O. sativa. Comparative analysis showed that O. sativa and O. officinalis shared high synteny of restriction fragment length polymorphism (RFLP) markers and low synteny of simple sequence repeat (SSR) markers. A DNA methylation alteration was revealed at C619 in the MAAL and progenies. Analysis of progenies of the MAAL indicated that introgression segments were small in size and introgression was not evenly distributed along the long arm. One recombination hot spot between C513 and RG177 was identified, which is in a gene-rich region.  相似文献   

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Summary Heracleum is a large and taxonomically complex genus of the Umbelliferae–Tordylieae. The phylogenetic relationships of West Asian Heracleum species and related taxa were explored using data from sequences of the internal transcribed spacer (ITS1 and ITS2) region of nuclear ribosomal DNA. The data set consists of 56 species, of which 47 were analyzed for the first time; it represents all subdivisions of the genus Heracleum, as well as some representatives of Pastinaca complex. Heracleum was shown to be a polyphyletic genus, as its species fall into two different clades, one of which comprises also Symphyoloma and Mandenovia. Section Pubescentia was confirmed, in contrast to the sections Villosa and Heracleum being polyphyletic. A separate position of the section Wendia was supported. H. marashicum was shown to be a member of a clade comprising Pastinaca and related genera. The sequences of chloroplast psbA-trnH intergenic spacer, the region recently proposed for DNA barcoding in plants, were also analyzed for 33 species, representing all principal clades within Heracleum and its relatives. They have been proven to be very similar and not suitable for DNA barcoding in this group. However, some sequence variation was revealed. This variation could be explained by the combination of such evolutionary events as inversion and duplication. It was shown that these events are rather common in Tordylieae and can occur independently in different lineages. The evolution patterns of psbA-trnH spacer are hypothesized.  相似文献   

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Biological Invasions - Assessing the effects of landscape composition on invasive and native wildlife abundance patterns is necessary to reach effective biodiversity management planning, especially...  相似文献   

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 The taxonomic status of three small [probably less than ca. 600 mm in the largest total length (TL)] and poorly known species, Trichiurus brevis Wang and You, 1992 and T. minor Li, 1992, both from South China Sea, and T. russelli Dutt and Thankam, 1966, from Bengal Bay, was reexamined. Trichiurus brevis and T. russelli, being valid species, are redescribed and a neotype is designated for the latter. Trichiurus brevis is considered to be a senior synonym of T. minor, there being no significant differences in their type specimens. Both valid species, i.e., T. brevis and T. russelli, are similar to T. lepturus Linnaeus, 1758 (larger than ca. 1000 mm TL) in general appearance, but clearly differ from the latter in having the top of the supraoccipital crest situated directly above the posterior margin of eye (vs. well behind posterior margin), lower number of total vertebrae (147–155 and 149–153, respectively, in the former two species vs. 168–173 in T. lepturus), longer dorsal fin base (mean 87% and mean 84% vs. mean 76% of TL), and shorter caudal peduncle length (6% and 8% vs. 13% of TL). Furthermore, the former two species are characterized by having the anal fin origin situated below about the 32nd–35th dorsal fin ray base, whereas in T. lepturus it is situated below the 37th–41st dorsal fin ray base. We recognize that T. brevis and T. russelli together comprise a species group, defined as the “T. russelli complex,” in the genus Trichiurus, the two species differing in snout shape (strongly pointed in T. brevis vs. moderately pointed in T. russelli), snout length [mean 35% vs. mean 30% of head length (HL)], preopercle length (22% vs. 19% HL), predorsal length (70% vs. 63% HL), and dermal eye opening (16% vs. 18% HL). Received: April 26, 2001 / Revised: January 19, 2002 / Accepted: February 1, 2002  相似文献   

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As published by the Intergovernmental Panel on Climate Change (IPCC) global warming is a reality and its impact is huge like the increase of extreme weather events, glacier recession, sea level rise and also effects on human health. Among them allergies to airborne pollen might increase or change in pattern due to the invasion of new allergic plants or due to different behavior of plants like earlier flowering. In this study we used the longest Swiss airborne pollen data set to examine the influence of the temperature increase on the time of flowering. In the case of Basel, where pollen data for 38 years are available, it was shown that due to a temperature increase the start of flowering in the case of birch occurred about 15 days earlier. Apart from a shift of the start of the flowering there is also a trend towards higher annual birch pollen quantities and an increase of the highest daily mean pollen concentrations. Due to global warming and because symptoms may appear earlier in the year people suffering from a pollen allergy might face a new unaccustomed situation.  相似文献   

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John C. Semple 《Brittonia》1978,30(4):492-495
Analysis of the type collections ofChrysopsis hyssopifolia Nutt. (Compositae),C. gigantea Small andC. mixta Dress indicates that all three are conspecific. On the other hand, plants identified by all authors asC. hyssopifolia were found not to be conspecific. A new name is here proposed for these plants,C. Iinearifolia Semple. Two subspecies are recognized, subsp.linearifolia confined to west Florida and subsp.dressii Semple, primarily confined to central peninsular Florida.  相似文献   

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Pyramimonas Schmarda is a genus of unicellular green flagellates, recorded in marine water and sea ice samples. Pyramimonas is within the prey size range of the most important protozoan grazers in Disko Bay, West Greenland, where this study took place. Despite the potential ecological importance, little is known about the occurrence of the genus. The aim of this study was to explore the biomass of Pyramimonas in developing stages of sea ice and in the water column. Pyramimonas colonized the early stages of sea ice, and the highest percent of Pyramimonas biomass was found in grease ice. The biomass of Pyramimonas was more than a magnitude higher within sea ice compared to the surface water. The results illustrate that Pyramimonas from the ice is an important contributor to the plankton community prior to the spring bloom. An undescribed species, Pyramimonas diskoicola sp. nov., was found. Based on morphology and ultrastructure, combined with molecular phylogeny inferred from the small-subunit SSU rDNA and the large-subunit chloroplast-encoded rbcL, the species was placed in subgenus Vestigifera. The cells possessed four flagella, measured 8.3 ± 2.6 μm in length and 5.1 ± 0.8 μm in width, and were characterized by an uplifted quadrant in the center of the box scales, not seen at any other Pyramimonas species. The phylogenetic analyses indicated P. diskoicola to be closely related to other polar sea ice species of Pyramimonas.  相似文献   

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Three new species of Metalasia from the Western Cape of South Africa are described; Metalasia tristis A.Bengtson & P.O.Karis, a small shrublet from the Groot Winterhoek Mountains, and Metalasia formosa A.Bengtson & P.O.Karis and Metalasia eburnea A.Bengtson & P.O.Karis both found in the Langeberg Mountains. The morphology and relationships of the three new species are discussed, and an updated key to the genus is provided.  相似文献   

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Polyomavirus infections are common and relatively benign in the general human population but can become pathogenic in immunosuppressed patients. Because most treatments for polyomavirus-associated diseases nonspecifically target DNA replication, existing treatments for polyomavirus infection possess undesirable side effects. However, all polyomaviruses express Large Tumor Antigen (T Ag), which is unique to this virus family and may serve as a therapeutic target. Previous screening of pyrimidinone–peptoid hybrid compounds identified MAL2-11B and a MAL2-11B tetrazole derivative as inhibitors of viral replication and T Ag ATPase activity (IC50 of ∼20–50 μM). To improve upon this scaffold and to develop a structure–activity relationship for this new class of antiviral agents, several iterative series of MAL2-11B derivatives were synthesized. The replacement of a flexible methylene chain linker with a benzyl group or, alternatively, the addition of an ortho-methyl substituent on the biphenyl side chain in MAL2-11B yielded an IC50 of ∼50 μM, which retained antiviral activity. After combining both structural motifs, a new lead compound was identified that inhibited T Ag ATPase activity with an IC50 of ∼5 μM. We suggest that the knowledge gained from the structure–activity relationship and a further refinement cycle of the MAL2-11B scaffold will provide a specific, novel therapeutic treatment option for polyomavirus infections and their associated diseases.  相似文献   

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