110 resultados para YELLOW WARBLERS


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The nucleotide sequence of the coat protein gene of barley yellow dwarf virus (BYDV, PAV serotype) was determined, and the amino acid sequence was deduced. The open reading frame, encoding a protein of relative molecular mass (Mr) 22,047, was confirmed as the coat protein gene by comparison with amino acid sequences of tryptic peptides derived from dissociated virions. In addition, a fragment of this gene expressed in Escherichia coli produced a product which was recognized by antibodies prepared against purified BYDV virions. An overlapping reading frame encoding an Mr 17,147 protein is contained completely within the coat protein gene. © 1988.

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We provide a taxonomic redescription of the ubiquitous and variable dasyurid marsupial Yellow-footed Antechinus, Antechinus flavipes (Waterhouse), which comprises three currently recognized subspecies whose combined geographic distribution spans almost the length and breadth of Australia. A. flavipes leucogaster Gray is confined to south-west Western Australia; A. flavipes flavipes is distributed in south-eastern Australia across four states—South Australia, Victoria, New South Wales and Queensland; A. flavipes rubeculus Van Dyck is confined to the wet tropics of Queensland. A. flavipes is readily distinguished from all extant congeners based on external morphology by the following combination of features: a grey head; orange-yellow toned flanks/rump, feet and tail base; pale eye-rings and a darkened tail tip. A. flavipes skulls are stout, being broad at the level of the rear upper molars, have small palatal vacuities and small entoconid cusps on the lower molars. However, notable differences among subspecies of A. flavipesprevent any obvious collection of skull characters being diagnostic for species-level discrimination among congeners. A. flavipes rubeculus is the largest of the three subspecies of Yellow-footed Antechinus and most similar in skull morphology to A. leo, A. bellus and A. godmani—all four species are geographically limited to tropical Australia. A. f. rubeculus is notably larger in many characters than its conspecifics: A. f. flavipes, the next largest, and A. f. leucogaster, the smallest of the group. A. f. flavipes and A. f. leucogaster diverge significantly at only a few skull characters, and both subspecies have cranial morphological affinities with the recently discovered A. mysticus, most notably A. f. leucogaster. Phylogenies generated from mt- and nDNA data strongly support Antechinus flavipes as monophyletic with respect to other members of the genus; within A. flavipes, each of the three recognized subspecies form distinctive monophyletic clades.

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In this paper, the complete mitochondrial genome of Acraea issoria (Lepidoptera: Nymphalidae: Heliconiinae: Acraeini) is reported; a circular molecule of 15,245 bp in size. For A. issoria, genes are arranged in the same order and orientation as the complete sequenced mitochondrial genomes of the other lepidopteran species, except for the presence of an extra copy of tRNAIle(AUR)b in the control region. All protein-coding genes of A. issoria mitogenome start with a typical ATN codon and terminate in the common stop codon TAA, except that COI gene uses TTG as its initial codon and terminates in a single T residue. All tRNA genes possess the typical clover leaf secondary structure except for tRNASer(AGN), which has a simple loop with the absence of the DHU stem. The sequence, organization and other features including nucleotide composition and codon usage of this mitochondrial genome were also reported and compared with those of other sequenced lepidopterans mitochondrial genomes. There are some short microsatellite-like repeat regions (e.g., (TA)9, polyA and polyT) scattered in the control region, however, the conspicuous macro-repeats units commonly found in other insect species are absent.

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This catalogue essay was written to accompany Eugenia Lim's 2015 exhibition at Metro Arts, Brisbane, 'Yellow Peril'. It discusses Lim's exploration of her identity as a Chinese-Australian, providing contextual information of Chinese immigration during Australia's gold rush years and the work of Hong Kong born American artist, Tseng Kwong Chi. It presents Yellow Peril as an exhibition that speaks critically about art and our cultural history amidst a fine layering of imagery, object and context, with a vitality that is derived from its rich and compelling base in real life moments and connections.

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Driving on an approach to a signalized intersection while distracted is relatively risky, as potential vehicular conflicts and resulting angle collisions tend to be relatively more severe compared to other locations. Given the prevalence and importance of this particular scenario, the objective of this study was to examine the decisions and actions of distracted drivers during the onset of yellow lights. Driving simulator data were obtained from a sample of 69 drivers under baseline and handheld cell phone conditions at the University of Iowa – National Advanced Driving Simulator. Explanatory variables included age, gender, cell phone use, distance to stop-line, and speed. Although there is extensive research on drivers’ responses to yellow traffic signals, the examinations have been conducted from a traditional regression-based approach, which do not necessary provide the underlying relations and patterns among the sampled data. In this paper, we exploit the benefits of both classical statistical inference and data mining techniques to identify the a priori relationships among main effects, non-linearities, and interaction effects. Results suggest that the probability of yellow light running increases with the increase in driving speed at the onset of yellow. Both young (18–25 years) and middle-aged (30–45 years) drivers reveal reduced propensity for yellow light running whilst distracted across the entire speed range, exhibiting possible risk compensation during this critical driving situation. The propensity for yellow light running for both distracted male and female older (50–60 years) drivers is significantly higher. Driver experience captured by age interacts with distraction, resulting in their combined effect having slower physiological response and being distracted particularly risky.

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Raman spectroscopic analyses of fragmented wall-painting specimens from a Romano-British villa dating from ca. 200 AD are reported. The predominant pigment is red haematite, to which carbon, chalk and sand have been added to produce colour variations, applied to a typical Roman limewash putty composition. Other pigment colours are identified as white chalk, yellow (goethite), grey (soot/chalk mixture) and violet. The latter pigment is ascribed to caput mortuum, a rare form of haematite, to which kaolinite (possibly from Cornwall) has been added, presumably in an effort to increase the adhesive properties of the pigment to the substratum. This is the first time that kaolinite has been reported in this context and could indicate the successful application of an ancient technology discovered by the Romano-British artists. Supporting evidence for the Raman data is provided by X-ray diffraction and SEM-EDAX analyses of the purple pigment.

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Through media such as newspapers, letterbox flyers, corporate brochures and television we are regularly confronted with descriptions for conventional (bricks 'n' mortar style) services. These representations vary in the terminology utilised, the depth of the description, the aspects of the service that are characterised and their applicability to candidate service requestors. Existing service catalogues (such as the Yellow Pages) provide little relief for service requestors from the burdensome task of discovering, comparing and substituting services. Add to this environment the rapidly evolving area of web services with its associated surfeit of standards, and the result is a considerably fragmented approach to the description of services. It leaves the reality of the Semantic Web somewhat clouded. --------- Let's consider service description briefly, before discussing our concerns with existing approaches to description. The act of describing is performed prior to advertising. This simple fact provides an interesting paradox as services cannot be described exactly before advertisement. This doesn't mean they can't be described comprehensively. By "exactly", we are referring to the fact that context provided by a service requestor (and their service needs) will alter the description of the service that is presented to the discoverer. For example, a service provider who operates a cinema wants to describe the price of their service. Let's say the advertised price is $15. They also want to state that a pensioner discount and a student discount is available which provides a 50% discount. A customer (i.e. service requestor) uses the cinema web site to purchase tickets online. They find the movie of their choice at a time that suits. However, its not until some context is provided by the requestor that the exact price is determined. The requestor might state that they are a pensioner. The same is applicable for a service requestor who purchases multiple tickets perhaps on behalf of other people. The disconnect between when the service is described and when a requestor provides context introduces challenges to the description process. A service provider would be ill-advised to offer independent descriptions that represent all the permutations possible for a single service. The descriptive effort would be prohibitive.

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The common brown leafhopper, Orosius orientalis (Matsumura) (Homoptera: Cicadellidae), previously described as Orosius argentatus (Evans), is an important vector of several viruses and phytoplasmas worldwide. In Australia, phytoplasmas vectored by O. orientalis cause a range of economically important diseases, including legume little leaf (Hutton & Grylls, 1956), tomato big bud (Osmelak, 1986), lucerne witches broom (Helson, 1951), potato purple top wilt (Harding & Teakle, 1985), and Australian lucerne yellows (Pilkington et al., 2004). Orosius orientalis also transmits Tobacco yellow dwarf virus (TYDV; genus Mastrevirus, family Geminiviridae) to beans, causing bean summer death disease (Ballantyne, 1968), and to tobacco, causing tobacco yellow dwarf disease (Hill, 1937, 1941). TYDV has only been recorded in Australia to date. Both diseases result in significant production and quality losses (Ballantyne, 1968; Thomas, 1979; Moran & Rodoni, 1999). Although direct damage caused by leafhopper feeding has been observed, it is relatively minor compared to the losses resulting from disease (P Tr E bicki, unpubl.).

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Isolating the impact of a colour, or a combination of colours, is extremely difficult to achieve because it is difficult to remove other environmental elements such as sound, odours, light, and occasion from the experience of being in a place. In order to ascertain the impact of colour on how we interpret the world in day to day situations, the current study records participant responses to achromatic scenes of the built environment prior to viewing the same scene in colour. A number of environments were photographed in colour or copied from design books; and copies of the images saved as both colour and black/grey/white. An overview of the study will be introduced by firstly providing examples of studies which have linked colour to meaning and emotions. For example, yellow is said to be connected to happiness1 ; or red evokes feelings of anger2 or passion. A link between colour and the way we understand and/or feel is established however, there is a further need for knowledge of colour in context. In response to this need, the current achromatic/chromatic environmental study will be described and discussed in light of the findings. Finally, suggestions for future research are posed. Based on previous research the authors hypothesised that a shift in environmental perception by participants would occur. It was found that the impact of colour includes a shift in perception of aspects such as its atmosphere and youthfulness. Through studio-class discussions it was also noted that the predicted age of the place, the function, and in association, the potential users when colour was added (or deleted) were often challenged. It is posited that the ability of a designer (for example, interior designer, architect, or landscape architect) to design for a particular target group—user and/or clients will be enhanced through more targeted studies relating colour in situ. The importance of noting the perceptual shift for the participants in our study, who were young designers, is the realisation that colour potentially holds the power to impact on the identity of an architectural form, an interior space, and/or particular elements such as doorways, furniture settings, and the like.

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Callus was initiated in three different ‘‘esculenta’’ taro cultivars by culturing corm slices in the dark on half-strength MS medium supplemented with 2.0 mg/l 2,4- dichlorophenoxyacetic acid (2,4-D) for 20 days followed by subculture of all corm slices to half-strength MS medium containing 1.0 mg/l thidiazuron (TDZ). Depending on the cultivar, 20–30% of corm slices produced compact, yellow, nodular callus on media containing TDZ. Histological studies revealed the presence of typical embryogenic cells which were small, isodiametric with dense cytoplasms. Somatic embryos formed when callus was transferred to hormone-free medium and *72% of the embryos germinated into plantlets on this medium. Simultaneous formation of roots and shoots during germination, and the presence of shoot and root poles revealed by histology, confirmed that these structures were true somatic embryos. Plants derived from somatic embryos appeared phenotypically normal following 2 months growth in a glasshouse. This method is a significant advance on those previously reported for the esculenta cultivars of taro due to its efficiency and reproducibility.

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Orosius orientalis is a leafhopper vector of several viruses and phytoplasmas affecting a broad range of agricultural crops. Sweep net, yellow pan trap and yellow sticky trap collection techniques were evaluated. Seasonal distribution of O. orientalis was surveyed over two successive growing seasons around the borders of commercially grown tobacco crops. Orosius orientalis seasonal activity as assessed using pan and sticky traps was characterised by a trimodal peak and relative abundance as assessed using sweep nets differed between field sites with peak activity occurring in spring and summer months. Yellow pan traps consistently trapped a higher number of O. orientalis than yellow sticky traps.

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Purpose: To determine (a) the effect of different sunglass tint colorations on traffic signal detection and recognition for color normal and color deficient observers, and (b) the adequacy of coloration requirements in current sunglass standards. Methods: Twenty color-normals and 49 color-deficient males performed a tracking task while wearing sunglasses of different colorations (clear, gray, green, yellow-green, yellow-brown, red-brown). At random intervals, simulated traffic light signals were presented against a white background at 5° to the right or left and observers were instructed to identify signal color (red/yellow/green) by pressing a response button as quickly as possible; response times and response errors were recorded. Results: Signal color and sunglass tint had significant effects on response times and error rates (p < 0.05), with significant between-color group differences and interaction effects. Response times for color deficient people were considerably slower than color normals for both red and yellow signals for all sunglass tints, but for green signals they were only noticeably slower with the green and yellow-green lenses. For most of the color deficient groups, there were recognition errors for yellow signals combined with the yellow-green and green tints. In addition, deuteranopes had problems for red signals combined with red-brown and yellow-brown tints, and protanopes had problems for green signals combined with the green tint and for red signals combined with the red-brown tint. Conclusions: Many sunglass tints currently permitted for drivers and riders cause a measurable decrement in the ability of color deficient observers to detect and recognize traffic signals. In general, combinations of signals and sunglasses of similar colors are of particular concern. This is prima facie evidence of a risk in the use of these tints for driving and cautions against the relaxation of coloration limits in sunglasses beyond those represented in the study.