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11.
12.
CHRISTINA M. COUSINS 《Journal of applied microbiology》1951,14(2):184-190
SUMMARY: The test is based on a colony count method to determine the survival of a given test organism, Bacterium coli , in the presence of sterile homogenized whole milk added with the bacterial suspension to the quaternary ammonium compound dilutions, for an exposure time of two min.
Attention is drawn to the special cleaning of the glassware used. The preparation and use of the Q.A.C. inhibitor, lecithin in 'Lissapol N', is described, with details of the testing procedure.
Inconsistencies in survivor counts occurring when Q.A.C. solutions were tested against saline suspensions of Bact. coli were reduced by carrying out the test in the presence of whole milk solids.
Examples quoted show how this test indicated a difference in bactericidal efficiency between (a) two different Q.A.C. solutions, and (b) the same Q.A.C. included in two powder formulations of differing pH value. 相似文献
Attention is drawn to the special cleaning of the glassware used. The preparation and use of the Q.A.C. inhibitor, lecithin in 'Lissapol N', is described, with details of the testing procedure.
Inconsistencies in survivor counts occurring when Q.A.C. solutions were tested against saline suspensions of Bact. coli were reduced by carrying out the test in the presence of whole milk solids.
Examples quoted show how this test indicated a difference in bactericidal efficiency between (a) two different Q.A.C. solutions, and (b) the same Q.A.C. included in two powder formulations of differing pH value. 相似文献
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Interest in bay scallop conservation has resulted in organized stock enhancement efforts and increased attention to fisheries management issues. Genetic markers can facilitate the monitoring of enhancement efforts, characterization of wild populations, and optimize hatchery practices. We have identified eight polymorphic simple sequence repeat markers including one dinucleotide, six trinucleotide and one compound dinucleotide repeats, in expressed sequence tags generated from multiple bay scallop cDNA libraries. The numbers of alleles range from two to five. The expected and observed heterozygosities range from 0.093 to 0.720 and 0.095 to 0.600, respectively. 相似文献
15.
RANDY W. DEYOUNG ANGELINE ZAMORANO BRIAN T. MESENBRINK TYLER A. CAMPBELL BRUCE R. LELAND GUY M. MOORE RODNEY L. HONEYCUTT J. JEFFREY ROOT 《The Journal of wildlife management》2009,73(8):1292-1299
ABSTRACT In west-central Texas, USA, abatement efforts for the gray fox (Urocyon cinereoargenteus) rabies epizootic illustrate the difficulties inherent in large-scale management of wildlife disease. The rabies epizootic has been managed through a cooperative oral rabies vaccination program (ORV) since 1996. Millions of edible baits containing a rabies vaccine have been distributed annually in a 16-km to 24-km zone around the perimeter of the epizootic, which encompasses a geographic area >4 × 105 km2. The ORV program successfully halted expansion of the epizootic into metropolitan areas but has not achieved the ultimate goal of eradication. Rabies activity in gray fox continues to occur periodically outside the ORV zone, preventing ORV zone contraction and dissipation of the epizootic. We employed a landscape-genetic approach to assess gray fox population structure and dispersal in the affected area, with the aim of assisting rabies management efforts. No unique genetic clusters or population boundaries were detected. Instead, foxes were weakly structured over the entire region in an isolation by distance pattern. Local subpopulations appeared to be genetically non-independent over distances >30 km, implying that long-distance movements or dispersal may have been common in the region. We concluded that gray foxes in west-central Texas have a high potential for long-distance rabies virus trafficking. Thus, a 16-km to 24-km ORV zone may be too narrow to contain the fox rabies epizootic. Continued expansion of the ORV zone, although costly, may be critical to the long-term goal of eliminating the Texas fox rabies virus variant from the United States. 相似文献
16.
CHRISTINA TORRES-ROUFF 《American anthropologist》2008,110(3):325-337
ABSTRACT Using a contextualized bioarchaeological framework, in this article, I examine the complex relationship between the Tiwanaku polity of the Bolivian altiplano (C.E. 550–1000) and the inhabitants of the San Pedro de Atacama oases of northern Chile, in Tiwanaku's far periphery. I focus on how influences from Tiwanaku might have affected the presentation of Atacameño group identity in the mortuary context. I compare skeletal and mortuary data from 300 individuals buried during the peak of Tiwanaku influence in the Atacama to assess mortuary context, trauma, and body modifications. Results suggest a complex response to Tiwanaku influence. Data from the grave and mortuary assemblage reveal traditional Atacameño tombs with occasional foreign objects. Evidence of increased traumatic injury suggests that this relationship was not without some conflict. Finally, the maintenance of bodily expressions of local identity indicates a society that used their bodies to mark Atacameño identity. 相似文献
17.
DAMIAN O. ELIAS WAYNE P. MADDISON CHRISTINA PECKMEZIAN MADELINE B. GIRARD ANDREW C. MASON 《Biological journal of the Linnean Society. Linnean Society of London》2012,105(3):522-547
Jumping spiders in the genus Habronattus use complex multimodal signals during courtship displays. In the present study, we describe multimodal displays from the Habronattus coecatus clade, comprising a diverse group of 23 described species. Habronattus coecatus group displays are made up of sex‐specific ornamentation and temporally coordinated combinations of motion displays and vibratory songs. Vibratory songs are complex, consisting of up to 20 elements organized in functional groupings (motifs) that change as courtship progresses. This temporal structuring of displays is analogous to a musical composition. Vibratory elements are associated with movement displays involving coloured and patterned ornaments on the male body. We describe general patterns of multimodal displays for 11 species including one, Habronattus borealis, which appears to have lost complex display behaviour. Habronattus coecatus group courtship is one of the most complex communication systems yet described in arthropods and this group may reveal important factors driving the evolution of complex signals. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 522–547. 相似文献
18.
MARTIN PÄCKERT CHRISTINA BLUME YUE-HUA SUN LIANG WEI JOCHEN MARTENS 《Biological journal of the Linnean Society. Linnean Society of London》2009,96(3):584-600
The present study evaluated the degree of differentiation between closely-related species of Blyth's leaf warbler complex ( Phylloscopus reguloides s.l. ) and white-tailed leaf warbler complex ( Phylloscopus davisoni s.l. ) by molecular (cytochrome b and 16S rRNA) and bioacoustic markers (sonagraphic analysis of songs). Molecular phylogenetic results corroborate the recently suggested splittings of the two former taxa into three and two species, respectively. By contrast to previous opinion, differentiation of territorial songs parallels the genetic diversification in both groups. In the P. reguloides group, all recently established species can be distinguished by a characteristic song pattern. Regularly structured songs composed of repeated two- or three-note syllables were found in all species of the group, whereas trill songs with single notes repeated are unique to Phylloscopus claudiae . The phylogenetic relationships of Phylloscopus occipitalis are ambiguous among different molecular trees, but song pattern clearly corroborates a close relationship to the P. reguloides group. In the white-tailed leaf warbler group, songs are irregularly structured and often descending in frequency with exception of P. davisoni and Phylloscopus ogilviegranti disturbans . Song pattern corroborates the genetic affiliation of Phylloscopus hainanus and Phylloscopus xanthoschistos to the molecular white-tailed leaf warbler clade. All target species correspond to distinct acoustic clusters resulting from discriminant analysis of several spectral and structural song parameters. Linear correlation between genetic and acoustic differentiation (pairwise p -distances versus difference of discriminant functions) is significant within both groups, except for one case, in which discriminant function 1 was correlated with a spectral parameter (minimum frequency) only. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 584–600. 相似文献
19.
The contribution of individual vascular bundles of the stemto the flow of assimilates from a selected source leaf to thesink regions was investigated inUrtica dioica L., a plant witha decussate leaf arrangement. Two homologous sets of eight vascularstrands were recognized, arranged in mirror symmetry in thestem internodes. In each set, three of the bundles were identifiedas traces of one leaf merging into the vascular system of thestem one node below the origin of the leaf. The main bundleof a stem-half bifurcates at each end of the internode intotwo subdominant bundles, which combine in the next but one nodeto form the dominant bundle again. Each set of vascular strandsalso contains two minor bundles which pass more or less withoutinterruption through the whole stem. The uppermost mature source leaf (leaf number 5 as counted fromthe tip) was exposed to14CO2in a closed gas circuit. The concentrationof the carbon-labelled CO2was maintained at the ambient CO2levelto maintain the natural source strength of the leaf. By theend of the usual nocturnal dark phase, carbon from the sourceleaf had been imported predominantly by sink leaves of the sameorthostichy. Lesser, but significant amounts of radiocarbonwere also incorporated into the sink leaves of the adjacenttwo orthostichies via the marginal leaf traces. In spite ofthe junction of the vascular strands in the nodes and an interfascicularconnection of the stem bundles, randomization of the photosynthatesfrom individual leaves was minimal in the vascular system ofthe stem in the upward direction, and also low in the flux tothe roots. Substantial amounts of radioactivity were also foundin the lately-formed xylem elements of the vascular strandsand their interfascicular connections, indicating active secondarygrowth. Assimilate distribution; sourcesink connections; Urtica dioica ; vascular architecture 相似文献
20.
LISA M. SCHLOEGEL LUÍS FELIPE TOLEDO JOYCE E. LONGCORE SASHA E. GREENSPAN CONRADO AUGUSTO VIEIRA MARIA LEE SERENA ZHAO CATHERINE WANGEN CLAUDIA MARIS FERREIRA MÁRCIO HIPOLITO ANGELA J. DAVIES CHRISTINA A. CUOMO PETER DASZAK TIMOTHY Y. JAMES 《Molecular ecology》2012,21(21):5162-5177
Global amphibian declines are linked with the presence of specific, highly virulent genotypes of the emerging fungal disease chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) known as the global panzootic lineage (Bd‐GPL). The global trade in amphibians for human consumption is suspected to have facilitated emergence of the disease, but evidence to support this is largely lacking. Here, we investigated the role the Lithobates catesbeianus (North American bullfrog) trade in spreading Bd genotypes by comparing strains associated with L. catesbeianus to a global panel using 36 sequenced loci from multiple chromosomal regions. Most bullfrogs were infected with Bd‐GPL genotypes, but we also detected novel, highly divergent Bd genotypes (Bd‐Brazil) from a live bullfrog in a US market and from native Brazilian anurans in the Atlantic Forest where bullfrogs are widely farmed. Sexual reproduction was also detected for the first time in Bd in the form of a hybrid genotype between the Bd‐GPL and Bd‐Brazil lineages in the Atlantic Forest. Despite the demonstration that ribosomal RNA types in Bd fail to undergo concerted evolution (over 20 sequence types may be found in a single strain), the Bd‐GPL and Bd‐Brazil lineages form largely separate clusters of related internal transcribed spacer (ITS) RNA sequences. Using ITS sequences, we then demonstrate the presence of Bd‐Brazil in Japan, primarily on invasive L. catesbeianus. The finding that Bd is capable of sexual reproduction between panzootic and endemic genotypes emphasizes the risk of international wildlife trade as a source of additional Bd epizootics owing to hybridization. 相似文献