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1.
Yuan Wang Jing Ji Tae-Kyun Oh Sung Oh Sue Hoon Kim Hyun Ju Lee Myoung Yong Shim Chang Won Choi Seong Hwan Kim Il-Seop Kim Young Shik Kim 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(3):361-370
Two newly emerged begomoviruses were isolated from naturally infected tomato (Solanum lycopersicum) plants grown in greenhouses at Jeju Island and Dangjin in Korea and their genomes were characterized. These viruses-infected plants had very small leaves that curled upward, yellow margins and a leathery appearance, and a bushy and stunted appearance with short internodes. Nucleotide (nt) sequence analysis of their genomes showed that they have a DNA-A component of a monopartite begomovirus. Their genomes comprised 2763 and 2764 nucleotides with six open reading frames. The results of nt sequence similarity analysis of DNA-A genome between the two Korean isolates and isolates of Tobacco leaf curl Japan virus (TbLCJV), Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and Eupatorium yellow vein virus in Japan (EpYVV) showed that they are likely similar to HYVV-[Masuda] (89.4–92.8% nt identity). Consequently, we tentatively propose the two isolates’ names as HYVV-Jeju and -DJ according to the ICTV geminivirus rules. Phylogenetic relationship analysis of 33 DNA-A genome sequences using PAUP* 4.0b10 and MrBayes revealed that HYVV-Jeju and -DJ belong to the Far East Asian begomovirus species complex. Within the Far East Asian begomovirus species complex, HYVV-Jeju and -DJ are distantly related to EpYVV, HYVMV, and TbLCJV groups. Based on the presence of a recombination fragment spanning the C3 ORF, a recombinant origin was suggested for both HYVV-Jeju and –DJ, with parents close to Japanese isolates HYVMV-[SP1:00] and Eupatorium yellow vein virus (EpYVV)-[Suya]. In addition, the presence of a further recombination fragment spanning the IR suggested the parents of HYVV-DJ were close to HYVV-Jeju and EpYVV-[Suya]. 相似文献
2.
Obtaining information on movement and spatial patterns of animals and understanding the factors that shape their movements about the landscape are critical steps in designing conservation strategies. We conducted a comparative radiotelemetry study of two snake species, the northern water snake, Nerodia sipedon sipedon, and the imperiled copperbelly water snake, Nerodia erythrogaster neglecta, in northwest Ohio and southern Michigan to assess differences in movement patterns, spatial ecology, and resource use. N. e. neglecta moved distances (53.3 ± 7.1 m/day and 4809 ± 603 m/year) over twice as far as N. s. sipedon (25.6 ± 2.7 m/day and 2244 ± 228 m/year), and used areas nearly four times larger (15.8 ± 2.7 ha) than N. s. sipedon (4.0 ± 0.9 ha). When wetlands were widely dispersed in the landscape, N. e. neglecta moved longer distances and used larger areas, whereas spatial and movement patterns in N. s. sipedon were unaffected by wetland spatial distribution. N. e. neglecta’s long movements and large area use are likely related to its use of variable resources such as ephemeral wetlands and anuran prey. N. s. sipedon used more permanent wetlands and preyed more generally on fish and anurans. Habitat alterations that change the spatial distribution of wetlands in the landscape, such as the loss of small isolated wetlands, have likely increased energetic costs and mortality rates for N. e. neglecta. Conservation strategies for vagile wetland animals that use spatially and temporally variable resources over broad spatial scales should focus on protecting and restoring large areas with numerous, heterogeneous wetlands. 相似文献
3.
Lactococcus lactis is a food-grade microorganism of major commercial importance. Antifreeze protein is a potent cryogenic protection agent for the cryopreservation of food and pharmaceutical materials. In this study, extracellular expression of a novel recombinant type I antifreeze protein analogue (rAFP) in L. lactis was optimized. An efficient SlpA promoter (P SlpA) was fused to various signal peptides (SPs) and propeptide sequences to examine the extracellular expression levels of rAFP. An efficient signal peptide, SP sacB, fused to prosequence AE, enabled higher extracellular rAFP production; use of the SlpA terminator (Ter SlpA) was a further improvement. The extracellularly expressed rAFP successfully inhibited ice recrystallization and is thus potentially applicable for cryogenic preservation. 相似文献
4.
Rawn DF Quade SC Sun WF Smith M Fouquet A Bélanger A 《Journal of agricultural and food chemistry》2008,56(3):916-921
Apples were sampled directly from orchard trees at 96, 45, and 21 days postapplication with one of three organophosphate insecticides (azinphos methyl, phosalone, or phosmet, respectively). Individual apples were prepared for analysis following one of three postharvest preparations: no preparation, rinsed with deionized water for 10-15 s, or rinsed and peeled. Azinphos methyl, phosalone, and phosmet concentrations ranged from below the level of detection to 5.26 ng/g, 94.7 to 5720 ng/g, and 0.011 to 663 ng/g in the apples that received no postharvest preparation, respectively. Although rinsed apples had lower maximum concentrations than observed in apples with no preparation, levels were not significantly lower. Concentrations of all three OP insecticides in apples that were rinsed followed by peeling, however, were much lower (below detection limits to 0.733 ng/g, azinphos methyl; 0.322-219 ng/g, phosalone; and below detection limits to 44.0 ng/g, phosmet) than observed in apples that had been rinsed alone. Rinsing and peeling of apples resulted in a 74.5-97.9% reduction in OP residues, while rinsing alone lowered mean concentrations by 13.5-28.7% relative to apples that received no postharvest preparation. 相似文献
5.
6.
Prevalence and epidemiology of the major gastrointestinal parasites of horses in Perth, Western Australia 总被引:2,自引:0,他引:2
A survey was conducted on the prevalence of the major gastrointestinal parasites in 140 horses necropsied in Perth, Western Australia, during 1979 to 1982. Adult Strongylus vulgaris were found in 22.5 per cent of horses and verminous arteritis in 62.9 per cent. The peak worm prevalence was in November to January (summer). S edentatus had a similar prevalence and seasonality but S equinus was not found in this survey. Draschia megastoma and Habronema muscae were found in 66.2 per cent and 35.3 per cent of horses respectively. Infection is probably acquired in summer when 8 per cent of the Musca domestica in the vicinity of the stables carried third stage spiruroid larvae. Gasterophilus intestinalis and G nasalis occurred in 36.4 per cent and 22.1 per cent of the horses respectively and 52.1 per cent of horses were infected with one or both species. The peak prevalence of G intestinalis larvae occurred in December with a trough in February-April; the peak prevalence of G nasalis was in May with a trough in November-December. Parascaris equorum was found in 9.9 per cent of the horses and in 21.3 per cent of those less than three years old. Anoplocephala perfoliata was found in 4.9 per cent of the horses and most of these were in older horses. 相似文献
7.
8.
Epstein E Norlyn JD Rush DW Kingsbury RW Kelley DB Cunningham GA Wrona AF 《Science (New York, N.Y.)》1980,210(4468):399-404
Increasing salinity of soil and water threatens agriculture in arid and semiarid regions. By itself, the traditional engineering approach to the problem is no longer adequate. Genetic science offers the possibility of developing salt-tolerant crops, which, in conjunction with environmental manipulation, could improve agricultural production in saline regions and extend agriculture to previously unsuited regions. 相似文献
9.
10.
Heterotopic ossification has not previously been described in the horse. An event horse was investigated due to poor performance and development of a hopping-type forelimb lameness when ridden. Comprehensive local analgesic techniques did not alter the hopping-type lameness. Radiological assessment revealed an osseous plate between the biceps brachii and brachiocephalicus muscles of the lame limb. Ultrasonographic examination verified that there was no involvement of the intertubercular bursa or tendon of biceps brachii or the muscles themselves. The horse was humanely destroyed because of multilimb lameness, with multiple sources of pain. Postmortem examination revealed a large plate of bone with very sharp, pointed margins, which was easily dissected from the adjacent muscles. The radiological and gross appearances of the bone plate were typical of heterotopic ossification in human beings. 相似文献