954 resultados para leaf nutrient content


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The Yd2 gene for “resistance” to barley yellow dwarf virus (BYDV) has been widely used in barley (Hordeum vulgare). We have tested Australian isolates of BYDV of varying severity against barley genotypes with and without the Yd2 gene and report here a positive relationship between symptoms and virus levels determined by ELISA. Cultivar Shannon is the result of backcrossing the resistant line CI 3208 to cultivar Proctor, a susceptible line. It appears to be intermediate in reaction to BYDV between Proctor and CI 3208, although it carries the major gene, Yd2. Unlike the whole plant studies, no significant differences were observed with regard to the ability of protoplasts derived from these various genotypes to support BYDV replication. It is therefore demonstrated for the first time that the Yd2 gene is not among the small number of resistance genes which are effective against virus replication in isolated protoplasts.

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Particles of carrot red leaf virus (CRLV; luteovirus group) purified from chervil (Anthriscus cerefolium) contain a single ssRNA species of mol. wt. about 1.8 x 106 and a major protein of mol. wt. about 25000. CRLV acts as a helper for aphid transmission of carrot mottle virus (CMotV; ungrouped) from mixedly infected plants. Virus preparations purified from such plants possess the infectivity of both viruses but contain particles indistinguishable from those of CRLV; some of the particles are therefore thought to consist of CMotV RNA packaged in CRLV coat protein. When RNA from such preparations was electrophoresed in agarose/polyacrylamide gels, CMotV infectivity was associated with an RNA band that migrated ahead of the CRLV RNA band and had an estimated mol. wt. of about 1.5 x 106, similar to that previously found for the infective ssRNA extracted directly from Nicotiana clevelandii leaves infected with CMotV alone. Preparations of dsRNA from CMotV-infected N. clevelandii leaves contained two species: one of mol. wt. about 3.2 x 106, presumably the replicative form of the infective ssRNA, and the other, mol. wt. about 0.9 x 106, of unknown origin and function. The infective agent in buffer extracts of CMotV-infected N. clevelandii was resistant to RNase (although the enzyme acted as a reversible inhibitor of infection at high concentrations) and is therefore not unprotected RNA. It may be protected within the approximately 52 nm enveloped structures previously reported.

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Particles of two isolates of subterranean clover red leaf virus were purified by a method in which infected plant tissue was digested with an industrial-grade cellulase, Celluclast® 2.0 L type X. The yields of virus particles using this enzyme were comparable with those obtained using either of two laboratory-grade cellulases, Cellulase type 1 (Sigma) and Driselase®. However, the specific infectivity or aphid transmissibility of the particles purified using Celluclast® was 10-100 times greater than those of preparations obtained using laboratory-grade cellulases or no enzyme. The main advantage of using Celluclast® is that at present in Australia its cost is only ca. 1% of laboratory-grade cellulases.

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A theoretical rationale, policy analysis and research agenda for a critical sociology of language and literacy curriculum, outlining the agenda for a political economy of textbooks.

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In Australia, protection orders are a key legal response to domestic violence, and are often viewed as a way of providing for victim safety. For instance, recently the joint Australian and New South Wales Law Reform Commissions recommended that a common core purpose of all state and territory domestic violence legislation should be ‘to ensure or maximise the safety and protection of persons who fear or experience family violence’ (2010:Recommendation 7-4). Drawing and building upon prior research in Australia and the United States (‘US’), this paper uses comparative quantitative content analysis to assess the victim safety focus of domestic violence protection order legislation in each Australian state and territory. The findings of this analysis show that the Northern Territory, South Australia and Victoria ‘stand out’ from the other jurisdictions, having the highest victim safety focus in their legislation. However, there remains sizeable scope for improvement in all Australian jurisdictions, in terms of the victim safety focus of their legislative provisions and the considerations of legislative inconsistency between jurisdictions.

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G protein-coupled receptors (GPCRs) are critical for cardiovascular physiology. Cardiac cells express >100 nonchemosensory GPCRs, indicating that important physiological and potential therapeutic targets remain to be discovered. Moreover, there is a growing appreciation that members of the large, distinct taste and odorant GPCR families have specific functions in tissues beyond the oronasal cavity, including in the brain, gastrointestinal tract and respiratory system. To date, these chemosensory GPCRs have not been systematically studied in the heart. We performed RT-qPCR taste receptor screens in rodent and human heart tissues that revealed discrete subsets of type 2 taste receptors (TAS2/Tas2) as well as Tas1r1 and Tas1r3 (comprising the umami receptor) are expressed. These taste GPCRs are present in cultured cardiac myocytes and fibroblasts, and are enriched in myocytes, which we corroborated using in situ hybridization. Tas1r1 gene-targeted mice (Tas1r1Cre/Rosa26tdRFP) strikingly recapitulated these data. In vivo taste receptor expression levels were developmentally regulated in the postnatal period. Intriguingly, several Tas2rs were upregulated in cultured rat myocytes and in mouse heart in vivo following starvation. The discovery of taste GPCRs in the heart opens an exciting new field of cardiac research. We predict that these taste receptors may function as nutrient sensors in the heart.

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Aim Facilities in retirement villages form a supportive environment for older residents. The purpose of this paper is to investigate the provision of these facilities in retirement villages, which are regarded as a viable accommodation option for the ever-increasing ageing population in Australia. Method A content analysis of 124 retirement villages operated by 22 developers in Queensland and South Australia was conducted for the research purpose. Results The most widely provided facilities are community centres, libraries, barbeque facilities, hairdressers/salons and billiards/snooker/pool tables. Commercial operators provide more facilities than not-for-profit organisations and larger retirement villages normally have more facilities due to the economics of scale involved. Conclusions The results of the study provide a useful reference for providing facilities within retirement villages that may support the quality lifestyles for the older residents.

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The characterization of X-ray diffraction, X-ray fluorescence, and field emission scanning electron microscope were used to confirm the successful preparation of Al-substituted goethite with different Al content. The micro-Raman spectroscopy was utilized to investigate the effect of Al content on the goethite lattice. The results show that all the feature bands of goethite shifted to high wavenumbers after the occurrence of Al substitution for Fe in the structure of goethite. The shift of wavenumber shows a good linear relationship as a function of increasing Al content especially for the band at 299 cm−1 (R2 = 0.9992). The in situ Raman spectroscopy of thermally treated goethite indicated that the Al substitution not only hinders the transformation of goethite, but also retarded the crystallization of thermally formed hematite. All the results indicated that Raman spectrum displayed an excellent performance in characterizing Al-substituted goethite, which implied the promising application in other substituted metal oxides or hydroxides.

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Debates about user-generated content (UGC) often depend on a contrast with its normative opposite, the professionally produced content that is supported and sustained by commercial media businesses or public organisations. UGC is seen to appear within or in opposition to professional media, often as a disruptive, creative, change-making force. Our suggestion is to position UGC not in opposition to professional or "producer media", or in hybridised forms of subjective combination with it (the so-called "pro-sumer" or "pro-am" system), but in relation to different criteria, namely the formal and informal elements in media industries. In this article, we set out a framework for the comparative and historical analysis of UGC systems and their relations with other formal and informal media activity, illustrated with examples ranging from games to talkback radio. We also consider the policy implications that emerge from a historicised reading of UGC as a recurring dynamic within media industries, rather than a manifestation of consumer agency specific to digital cultures.

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This Article is about legal scholarly publication in a time of plenitude. It is an attempt to explain why the most pressing questions in legal scholarly publishing are about how we ensure access to an infinity of content. It explains why standard assumptions about resource scarcity in publication are wrong in general, and how the changes in the modality of publication affect legal scholarship. It talks about the economics of open access to legal material, and how this connects to a future where there is infinite content. And because student-edited law reviews fit this future better than their commercially-produced, peer-refereed cousins, this Article is, in part, a defense of the crazy-beautiful institution that is the American law review.

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Researchers from Queensland University of Technology have teamed up with the Australian Research Council (ARC), Screen Australia, The Australian Broadcasting Corporation (ABC), the Special Broadcasting Service (SBS) and the Australian Children’s Television Foundation (ACTF) to investigate the use of Australian screen content in primary, secondary and tertiary education. Over the next three years (2014-2016), researchers and investigators will undertake a national survey of schools and universities, and will conduct in-depth interviews with hundreds of industry representatives, teachers, principals, librarians and students. Furthermore, new approaches to developing screen content and curricula will be trialled. The project aims to develop a comprehensive picture of why, how, how much and where Australian screen content is used in education.

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High-temperature, low-light (HTLL) treatment of 35S:PAP1 Arabidopsis thaliana over-expressing the PAP1 (Production of Anthocyanin Pigment 1) gene results in reversible reduction of red colouration, suggesting the action of additional anthocyanin regulators. High-performance liquid chromatography (HPLC), liquid chromatography mass spectrometry (LCMS) and Affimetrix®-based microarrays were used to measure changes in anthocyanin, flavonoids, and gene expression in response to HTLL. HTLL treatment of control and 35S:PAP1 A. thaliana resulted in a reversible reduction in the concentrations of major anthocyanins despite ongoing over-expression of the PAP1 MYB transcription factor. Twenty-one anthocyanins including eight cis-coumaryl esters were identified by LCMS. The concentrations of nine anthocyanins were reduced and those of three were increased, consistent with a sequential process of anthocyanin degradation. Analysis of gene expression showed down-regulation of flavonol and anthocyanin biosynthesis and of transport-related genes within 24 h of HTLL treatment. No catabolic genes up-regulated by HTLL were found. Reductions in the concentrations of anthocyanins and down-regulation of the genes of anthocyanin biosynthesis were achieved by environmental manipulation, despite ongoing over-expression of PAP1. Quantitative PCR showed reduced expression of three genes (TT8, TTG1 and EGL3) of the PAP1 transcriptional complex, and increased expression of the potential transcriptional repressors AtMYB3, AtMYB6 and AtMYBL2 coincided with HTLL-induced down-regulation of anthocyanin biosynthesis. HTLL treatment offers a model system with which to explore anthocyanin catabolism and to discover novel genes involved in the environmental control of anthocyanins.