56 research outputs found
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The regulation of television sports broadcasting: a comparative analysis
Based on seven different sports broadcasting markets (Australia, Brazil, Italy, India, South Africa, United Kingdom and the United States), this article provides a comparative analysis of the regulation of television sports broadcasting. The article examines how contrasting perspectives on television and sport â economic and sociocultural â have been reflected in two main approaches to the regulation of sports broadcasting, namely competition law and major events legislation. The results of this analysis suggest that in many cases, the balance between commerce and culture in sports broadcasting has shifted too far in favour of the commercial interests of dominant pay-TV operators and sports organisations. Here, the case is made for the pursuit of an approach to sports broadcasting regulation that seeks to balance the commercial priorities of broadcasters and sports organisations with the wider sociocultural benefits citizens gain from freeto- air sports broadcasting
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Characteristics of the memory sources of dreams: A new version of the content-matching paradigm to take mundane and remote memories into account
Several studies have demonstrated that dream content is related to the waking life of the dreamer. However, the characteristics of the memory sources incorporated into dreams are still unclear. We designed a new protocol to investigate remote memories and memories of trivial experiences, both relatively unexplored in dream content until now. Upon awakening, for 7 days, participants identified the waking life elements (WLEs) related to their dream content and characterized them and their dream content on several scales to assess notably emotional valence. Thanks to this procedure, they could report WLEs from the whole lifespan, and mundane ones before they had been forgotten. Participants (N = 40, 14 males, age = 25.2 ± 7.6) reported 6.2 ± 2.0 dreams on average. For each participant, 83.4% ± 17.8 of the dream reports were related to one or more WLEs. Among all the WLEs incorporated into dreams dated by the participants (79.3 ± 19%), 40.2 ± 30% happened the day before the dream, 26.1 ± 26% the month before (the day before excluded), 15.8 ± 21% the year before the dream (the month before excluded), and 17.9 ± 24% happened more than one year before the dream. As could be expected from previous studies, the majority of the WLEs incorporated into dreams were scored as important by the dreamers. However, this was not true for incorporated WLEs dating from the day before the dream. In agreement with Freudâs observations, the majority of the day residues were scored as mundane. Finally, for both positive and negative WLEs incorporated into dreams, the dreamt version of the WLE was rated as emotionally less intense than the original WLE. This result, showing that dreams tend to attenuate the emotional tone of waking-life memories towards a more neutral one, argues in favor of the emotional regulation hypothesis of dreaming
Cochliobolus heterostrophus (Drechsler) Drechsler,(1934)
Cochliobolus heterostrophus (anamorph, Bipolaris maydis) is a necrotophic, hetrothallic fungus which infects the leaves of maize. The species is subdivided into three races: race O, race T and race C. Race T is the most virulent to maize plants carrying the Texas cytoplasmic male sterile trait due to presence of approx. 1.2 Mb of DNA encoding genes for T-toxin production. Other members of the genus include the necrotrophic corn pathogen Cochliobolus carbonum, the oat pathogen, Cochliobolus victoriae, the rice pathogen, Cochliobolus miyabeanus, the sorghum pathogen, Bipolaris sorghicola, the sugarcane pathogen, Bipolaris sacchari, and the hemibiotrophic generalized cereal and grass pathogen, Cochliobolus sativus. All species mentioned above produce host selective toxins
Rapid screening method of Saccharomyces cerevisiae mutants using calcofluor white and aniline blue.
Fungal cell walls are composed of polysaccharide scaffold that changes in response to environment. The structure and biosynthesis of the wall are unique to fungi, with plant and mammalian immune systems evolved to recognize wall components. Additionally, the enzymes that assemble fungal cell wall components are excellent targets for antifungal chemotherapies and fungicides. Understanding changes in the cell wall are important for fundamental understanding of cell wall dynamics and for drug development. Here we describe a screening technique to monitor the gross morphological changes of two key cell wall polysaccharides of chitin and ÎČ-1,3-glucan combined with polymerase chain reaction (PCR) genotyping. Changes in chitin and ÎČ-1,3-glucan were detected microscopically by using the dyes calcofluor white and aniline blue. Combining PCR and fluorescence microscopy, as a quick and easy screening technique, confirmed both the phenotype and genotype of the wild-type, h chitin synthase mutants (chs1Î and chs3Î) and one ÎČ-1,3-glucan synthase mutant fks2Î from Saccharomyces cerevisiae knockout library. This combined screening method highlighted that the fks1Î strain obtained commercially was in fact not FKS1 deletion strain, and instead had both wild-type genotype and phenotype. A new ÎČ-1,3-glucan synthase knockout fks1::URA3 strain was created. Fluorescence microscopy confirmed its phenotype revealing that the chitin and the new ÎČ-1,3-glucan profiles were elevated in the mother cells and in the emerging buds respectively in the fks1Î cell walls. This combination of PCR with fluorescence microscopy is a quick and easy screening method to determine and verify morphological changes in the S. cerevisiae cell wall
Propidium iodide enabled live imaging of Pasteuria sp.-Pratylenchus zeae infection studies under fluorescence microscopy.
Live imaging allows observations of cell structures and processes in real time, to monitor dynamic changes within living organisms compared to fixed organisms. Fluorescence microscopy was used to monitor the dynamic infection process of the nematode parasitic bacterium Pasteuria sp. and the sugarcane root-lesion nematode, Pratylenchus zeae. Under fluorescence microscopy, green-autofluorescent globules were observed in live control and Pasteuria sp.-infected nematodes. Only nematodes killed by Pasteuria sp. or heat treated displayed a diffuse pattern of autofluorescence. Propidium iodide (PI), used as a cell membrane integrity indicator, confirmed that the nematode's cuticle acts as an impermeable barrier. PI stained cells/DNA of heat-treated control and Pasteuria sp.-infected P. zeae. PI as a counterstain facilitated the location of Pasteuria endospores on the cuticle surface of P. zeae. No PI staining was observed in sporangia and in endospores within the nematode body. However, PI specifically stained endospores on the cuticle surface and within the cuticle carcass showing, in mature propagules, a ring-like pattern. Live imaging, combined with fluorescence microscopy and fluorescent dyes such as PI, appears useful in live studies on plant nematode interactions with nematophagous bacteria
The localization of auxin transporters PIN3 and LAX3 during lateral root development in Arabidopsis thaliana
International audienc
Pathogenicity of migratory endoparasitic nematodes on coffee seedlings (Coffea arabica cv. K7) in Australia
Plant-parasitic nematodes cause significant losses to coffee globally, but to date, there have been no reports of nematodes causing adverse effects to coffee crops in Australia. Four species of migratory endoparasitic nematodes, including Pratylenchus coffeae, Pratylenchus brachyurus, Pratylenchus zeae, and Radopholus similis, were detected in coffee-growing areas of Australia and their molecular data were also deposited in GenBank under accession numbers MN796428, MN718729, MN831891, and MN796426 respectively. A pathogenicity test of these nematode species was performed on seedlings of Coffea arabica cv. K7 under glasshouse conditions. We found that seedlings inoculated with P. coffeae and R. similis (both isolated from banana roots) and P. brachyurus (isolated from coffee roots), were stunted and their root systems were severely damaged. Tap roots and lateral roots of Coffea arabica cv. K7 were destroyed by P. coffeae, whereas P. brachyurus, and R. similis mainly damaged tap roots. Pratylenchus zeae, originally isolated from Saccharum spp., was not pathogenic to Coffea arabica cv. K7. This is the first report of nematode species capable of damaging coffee in Australia and the results demonstrate that nematodes pose a potential threat to coffee production
Early development and gravitropic response of lateral roots in Arabidopsis thaliana
Root system architecture plays an important role in determining nutrient and water acquisition and is modulated by endogenous and environmental factors, resulting in considerable developmental plasticity. The orientation of primary root growth in response to gravity (gravitropism) has been studied extensively, but little is known about the behaviour of lateral roots in response to this signal. Here, we analysed the response of lateral roots to gravity and, consistently with previous observations, we showed that gravitropism was acquired slowly after emergence. Using a lateral root induction system, we studied the kinetics for the appearance of statoliths, phloem connections and auxin transporter gene expression patterns. We found that statoliths could not be detected until 1 day after emergence, whereas the gravitropic curvature of the lateral root started earlier. Auxin transporters modulate auxin distribution in primary root gravitropism. We found differences regarding PIN3 and AUX1 expression patterns between the lateral root and the primary root apices. Especially PIN3, which is involved in primary root gravitropism, was not expressed in the lateral root columella. Our work revealed new developmental transitions occurring in lateral roots after emergence, and auxin transporter expression patterns that might explain the specific response of lateral roots to gravity
The Arabidopsis NRT1.1 transceptor coordinately controls auxin biosynthesis and transport to regulate root branching in response to nitrate
In agricultural systems, nitrate is the main source of nitrogen available for plants. Besides its role as a nutrient, nitrate has been shown to act as a signal molecule for plant growth, development and stress responses. In Arabidopsis, the NRT1.1 nitrate transceptor represses lateral root (LR) development at low nitrate availability by promoting auxin basipetal transport out of the LR primordia (LRPs). In addition, our present study shows that NRT1.1 acts as a negative regulator of the TAR2 auxin biosynthetic gene expression in the root stele. This is expected to repress local auxin biosynthesis and thus to reduce acropetal auxin supply to the LRPs. Moreover, NRT1.1 also negatively affects expression of the LAX3 auxin influx carrier, thus preventing cell wall remodeling required for overlying tissues separation during LRP emergence. Both NRT1.1-mediated repression of TAR2 and LAX3 are suppressed at high nitrate availability, resulting in the nitrate induction of TAR2 and LAX3 expression that is required for optimal stimulation of LR development by nitrate. Altogether, our results indicate that the NRT1.1 transceptor coordinately controls several crucial auxin-associated processes required for LRP development, and as a consequence that NRT1.1 plays a much more integrated role than previously anticipated in regulating the nitrate response of root system architecture
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