888 research outputs found
A comparative strategic analysis of China Airlines and EVA Air
The two biggest airlines in Taiwan – China Airlines and EVA Air – face a wide range of similar strategic opportunities and challenges, while also pursuing considerably different strategic priorities in some key areas. This paper conducts a comparative strategic analysis of these two airlines by considering the key success factors (KSFs) of fleet mix and size, international partnerships and cooperation, network scope and global reach, and brand awareness and loyalty. Despite geopolitical restrictions, both carriers have developed sizable fleets, networks and partnerships with a global ambition, effectively creating a duopoly that controls half of the passenger market and almost two-thirds of the cargo market in Taiwan. Their brands are recognized outside Taiwan, although EVA Air enjoys slightly better perception of quality by rating companies and passengers. Yet, external realities have greater potential to determine each airline's future strategic trajectory, rather than internal KSFs. Both airlines help to illustrate the global connectivity that the airline industry can foster and promote, and each provides a counterbalance to regional tensions and divisions by doing so
Vision 2030 and prospects for network airlines in Saudi Arabia
In: 12th International Conference on Air Transport – INAIR 2023, The Future of Aviation – is the Sky the Limit?The air transport industry in Saudi Arabia is experiencing rapid growth of late, fuelled in large part by the Kingdom's Vision 2030 aspirations and national development plan. This ambitious national vision seeks to diversify the Kingdom's economy, and in the process, develop and expand a wide range of industry and public sectors. Central to these plans is air transport, including not only the building of new airports and related transport infrastructure, along with expanding the wider travel and hospitality sectors, but also the launch of a new network airline in 2025 – Riyadh Air. This new airline will join current national flag carrier Saudia, and together they will play central roles in growing both the domestic and international air markets in the Kingdom, mainly out of the two main hubs Riyadh Airport (RUH) and Jeddah Airport (JED). The paper here aims to assess this coming network carrier duopoly, including the future prospects for both airlines as they seek to compete in a region, and indeed globally, against well-established legacy and flag carriers. Evidently, the future of network airlines in KSA could very well shape and determine prospects for the industry more generally for decades to come
Avihepadnavirus diversity in parrots is comparable to that found amongst all other avian species
Avihepadna viruses have previously been isolated from various species of duck ,goose, stork, heron and
crane. Recently the first parrot avihepadna virus was isolated from a Ring-necked Parakeet in Poland. In
this study, 41 psittacineliver samples archived in Poland over the last nine years were tested for
presence of Parrot hepatitis B virus(PHBV). We cloned and sequenced PHBVisolates from 18 birds
including a Crimson Rosella, an African grey parrot and sixteen Ring-necked Parakeets. PHBVisolates
display a degree of diversity (478% genome wide pair wise identity) that is comparable to that found
amongst all other avihepadna viruses (479% genome wide pair wise identity). The PHBV viruses can be
subdivided into seven genetically distinct groups (tentatively named A-G) of which the two isolated of
PHBV-Gare the most divergent sharing 79% genome wide pair wise identity with all their PHBVs. All
PHBV isolates display classical avihepadnavirus genome architecture.Department of HE and Training approved lis
The Maunakea Spectroscopic Explorer Book 2018
(Abridged) This is the Maunakea Spectroscopic Explorer 2018 book. It is
intended as a concise reference guide to all aspects of the scientific and
technical design of MSE, for the international astronomy and engineering
communities, and related agencies. The current version is a status report of
MSE's science goals and their practical implementation, following the System
Conceptual Design Review, held in January 2018. MSE is a planned 10-m class,
wide-field, optical and near-infrared facility, designed to enable
transformative science, while filling a critical missing gap in the emerging
international network of large-scale astronomical facilities. MSE is completely
dedicated to multi-object spectroscopy of samples of between thousands and
millions of astrophysical objects. It will lead the world in this arena, due to
its unique design capabilities: it will boast a large (11.25 m) aperture and
wide (1.52 sq. degree) field of view; it will have the capabilities to observe
at a wide range of spectral resolutions, from R2500 to R40,000, with massive
multiplexing (4332 spectra per exposure, with all spectral resolutions
available at all times), and an on-target observing efficiency of more than
80%. MSE will unveil the composition and dynamics of the faint Universe and is
designed to excel at precision studies of faint astrophysical phenomena. It
will also provide critical follow-up for multi-wavelength imaging surveys, such
as those of the Large Synoptic Survey Telescope, Gaia, Euclid, the Wide Field
Infrared Survey Telescope, the Square Kilometre Array, and the Next Generation
Very Large Array.Comment: 5 chapters, 160 pages, 107 figure
Identifying and Seeing beyond Multiple Sequence Alignment Errors Using Intra-Molecular Protein Covariation
BACKGROUND: There is currently no way to verify the quality of a multiple sequence alignment that is independent of the assumptions used to build it. Sequence alignments are typically evaluated by a number of established criteria: sequence conservation, the number of aligned residues, the frequency of gaps, and the probable correct gap placement. Covariation analysis is used to find putatively important residue pairs in a sequence alignment. Different alignments of the same protein family give different results demonstrating that covariation depends on the quality of the sequence alignment. We thus hypothesized that current criteria are insufficient to build alignments for use with covariation analyses.
METHODOLOGY/PRINCIPAL FINDINGS: We show that current criteria are insufficient to build alignments for use with covariation analyses as systematic sequence alignment errors are present even in hand-curated structure-based alignment datasets like those from the Conserved Domain Database. We show that current non-parametric covariation statistics are sensitive to sequence misalignments and that this sensitivity can be used to identify systematic alignment errors. We demonstrate that removing alignment errors due to 1) improper structure alignment, 2) the presence of paralogous sequences, and 3) partial or otherwise erroneous sequences, improves contact prediction by covariation analysis. Finally we describe two non-parametric covariation statistics that are less sensitive to sequence alignment errors than those described previously in the literature.
CONCLUSIONS/SIGNIFICANCE: Protein alignments with errors lead to false positive and false negative conclusions (incorrect assignment of covariation and conservation, respectively). Covariation analysis can provide a verification step, independent of traditional criteria, to identify systematic misalignments in protein alignments. Two non-parametric statistics are shown to be somewhat insensitive to misalignment errors, providing increased confidence in contact prediction when analyzing alignments with erroneous regions because of an emphasis on they emphasize pairwise covariation over group covariation
Evidence that dicot-infecting mastreviruses are particularly prone to inter-species recombination and have likely been circulating in Australia for longer than in Africa and the Middle East
Viruses of the genus Mastrevirus (family Geminiviridae) are transmitted by leafhoppers and infect either mono- or dicotyledonous plants. Here we have determined the full length sequences of 49 dicot-infecting mastrevirus isolates sampled in Australia, Eritrea, India, Iran, Pakistan, Syria, Turkey and Yemen. Comprehensive analysis of all available dicot-infecting mastrevirus sequences showed the diversity of these viruses in Australia to be greater than in the rest of their known range, consistent with earlier studies, and that, in contrast with the situation in monocot-infecting mastreviruses, detected inter-species recombination events outnumbered intra-species recombination events. Consistent with Australia having the greatest diversity of known dicot-infecting mastreviruses phylogeographic analyses indicating the most plausible scheme for the spread of these viruses to their present locations, suggest that most recent common ancestor of these viruses is likely nearer Australia than it is to the other regions investigated.Department of HE and Training approved lis
Comparative Genome Analysis Reveals an Absence of Leucine-Rich Repeat Pattern-Recognition Receptor Proteins in the Kingdom Fungi
Background: In plants and animals innate immunity is the first line of defence against attack by microbial pathogens. Specific molecular features of bacteria and fungi are recognised by pattern recognition receptors that have extracellular domains containing leucine rich repeats. Recognition of microbes by these receptors induces defence responses that protect hosts against potential microbial attack. Methodology/Principal Findings: A survey of genome sequences from 101 species, representing a broad cross-section of the eukaryotic phylogenetic tree, reveals an absence of leucine rich repeat-domain containing receptors in the fungal kingdom. Uniquely, however, fungi possess adenylate cyclases that contain distinct leucine rich repeat-domains, which have been demonstrated to act as an alternative means of perceiving the presence of bacteria by at least one fungal species. Interestingly, the morphologically similar osmotrophic oomycetes, which are taxonomically distant members of the stramenopiles, possess pattern recognition receptors with similar domain structures to those found in plants. Conclusions: The absence of pattern recognition receptors suggests that fungi may possess novel classes of patternrecognition receptor, such as the modified adenylate cyclase, or instead rely on secretion of anti-microbial secondary metabolites for protection from microbial attack. The absence of pattern recognition receptors in fungi, coupled with their abundance in oomycetes, suggests this may be a unique characteristic of the fungal kingdom rather than a consequence o
Do Behavioral Foraging Responses of Prey to Predators Function Similarly in Restored and Pristine Foodwebs?
Efforts to restore top predators in human-altered systems raise the question of whether rebounds in predator populations are sufficient to restore pristine foodweb dynamics. Ocean ecosystems provide an ideal system to test this question. Removal of fishing in marine reserves often reverses declines in predator densities and size. However, whether this leads to restoration of key functional characteristics of foodwebs, especially prey foraging behavior, is unclear. The question of whether restored and pristine foodwebs function similarly is nonetheless critically important for management and restoration efforts. We explored this question in light of one important determinant of ecosystem function and structure – herbivorous prey foraging behavior. We compared these responses for two functionally distinct herbivorous prey fishes (the damselfish Plectroglyphidodon dickii and the parrotfish Chlorurus sordidus) within pairs of coral reefs in pristine and restored ecosystems in two regions of these species' biogeographic ranges, allowing us to quantify the magnitude and temporal scale of this key ecosystem variable's recovery. We demonstrate that restoration of top predator abundances also restored prey foraging excursion behaviors to a condition closely resembling those of a pristine ecosystem. Increased understanding of behavioral aspects of ecosystem change will greatly improve our ability to predict the cascading consequences of conservation tools aimed at ecological restoration, such as marine reserves
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Managing Oil Palm Plantations More Sustainably: Large-Scale Experiments Within the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Programme
Conversion of tropical forest to agriculture results in reduced habitat heterogeneity, and associated declines in biodiversity and ecosystem functions. Management strategies to increase biodiversity in agricultural landscapes have therefore often focused on increasing habitat complexity; however, the large-scale, long-term ecological experiments that are needed to test the effects of these strategies are rare in tropical systems. Oil palm (Elaeis guineensis Jacq.)—one of the most widespread and important tropical crops—offers substantial potential for developing wildlife-friendly management strategies because of its long rotation cycles and tree-like structure. Although there is awareness of the need to increase sustainability, practical options for how best to manage oil palm plantations, for benefits to both the environment and crop productivity, have received little research attention. In this paper we introduce the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Programme: a long-term research collaboration between academia and industry in Sumatra, Indonesia. The BEFTA Programme aims to better understand the oil palm agroecosystem and test sustainability strategies. We hypothesise that adjustments to oil palm management could increase structural complexity, stabilise microclimate, and reduce reliance on chemical inputs, thereby helping to improve levels of biodiversity and ecosystem functions. The Programme has established four major components: (1) assessing variability within the plantation under business-as-usual conditions; (2) the BEFTA Understory Vegetation Project, which tests the effects of varying herbicide regimes; (3) the Riparian Ecosystem Restoration in Tropical Agriculture (RERTA) Project, which tests strategies for restoring riparian habitat; and (4) support for additional collaborative projects within the Programme landscape. Across all projects, we are measuring environmental conditions, biodiversity, and ecosystem functions. We also measure oil palm yield and production costs, in order to assess whether suggested sustainability strategies are feasible from an agronomic perspective. Early results show that oil palm plantation habitat is more variable than might be expected from a monoculture crop, and that everyday vegetation management decisions have significant impacts on habitat structure. The BEFTA Programme highlights the value of large-scale collaborative projects for understanding tropical agricultural systems, and offers a highly valuable experimental set-up for improving our understanding of practices to manage oil palm more sustainably
Geometagenomics illuminates the impact of agriculture on the distribution and prevalence of plant viruses at the ecosystem scale
Disease emergence events regularly result from human activities such as agriculture, which
frequently brings large populations of genetically uniform hosts into contact with potential
pathogens. Although viruses cause nearly 50% of emerging plant diseases, there is little systematic
information about virus distribution across agro-ecological interfaces and large gaps in understanding
of virus diversity in nature. Here we applied a novel landscape-scale geometagenomics
approach to examine relationships between agricultural land use and distributions of plantassociated
viruses in two Mediterranean-climate biodiversity hotspots (Western Cape region of
South Africa and Rhône river delta region of France). In total, we analysed 1725 geo-referenced plant
samples collected over two years from 4.5 × 4.5 km2 grids spanning farmlands and adjacent
uncultivated vegetation. We found substantial virus prevalence (25.8–35.7%) in all ecosystems, but
prevalence and identified family-level virus diversity were greatest in cultivated areas, with some
virus families displaying strong agricultural associations. Our survey revealed 94 previously
unknown virus species, primarily from uncultivated plants. This is the first effort to systematically
evaluate plant-associated viromes across broad agro-ecological interfaces. Our findings indicate that
agriculture substantially influences plant virus distributions and highlight the extent of current
ignorance about the diversity and roles of viruses in nature
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