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1.
Risk Anal ; 39(5): 1022-1043, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30408211

RESUMO

Space weather phenomena have been studied in detail in the peer-reviewed scientific literature. However, there has arguably been scant analysis of the potential socioeconomic impacts of space weather, despite a growing gray literature from different national studies, of varying degrees of methodological rigor. In this analysis, we therefore provide a general framework for assessing the potential socioeconomic impacts of critical infrastructure failure resulting from geomagnetic disturbances, applying it to the British high-voltage electricity transmission network. Socioeconomic analysis of this threat has hitherto failed to address the general geophysical risk, asset vulnerability, and the network structure of critical infrastructure systems. We overcome this by using a three-part method that includes (i) estimating the probability of intense magnetospheric substorms, (ii) exploring the vulnerability of electricity transmission assets to geomagnetically induced currents, and (iii) testing the socioeconomic impacts under different levels of space weather forecasting. This has required a multidisciplinary approach, providing a step toward the standardization of space weather risk assessment. We find that for a Carrington-sized 1-in-100-year event with no space weather forecasting capability, the gross domestic product loss to the United Kingdom could be as high as £15.9 billion, with this figure dropping to £2.9 billion based on current forecasting capability. However, with existing satellites nearing the end of their life, current forecasting capability will decrease in coming years. Therefore, if no further investment takes place, critical infrastructure will become more vulnerable to space weather. Additional investment could provide enhanced forecasting, reducing the economic loss for a Carrington-sized 1-in-100-year event to £0.9 billion.

2.
Arch Virol ; 163(3): 815-817, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29224129

RESUMO

A recent proposal that the genus Rymovirus be assimilated into the genus Potyvirus is examined, discussed, and rejected. It illustrates the danger of using 'sequence identity' as a proxy for phylogenetic relatedness to distinguish closely related but distinct groups of viruses.


Assuntos
Genoma Viral , Filogenia , Potyviridae/classificação , Potyvirus/classificação , RNA Viral/genética , Sequência de Bases , Evolução Biológica , Biologia Computacional/métodos , Potyviridae/genética , Potyvirus/genética , Análise de Sequência de RNA , Homologia de Sequência do Ácido Nucleico , Terminologia como Assunto
3.
Proc Natl Acad Sci U S A ; 107(21): 9485-9, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20435916

RESUMO

Globally, many fish species are overexploited, and many stocks have collapsed. This crisis, along with increasing concerns over flow-on effects on ecosystems, has caused a reevaluation of traditional fisheries management practices, and a new ecosystem-based fisheries management (EBFM) paradigm has emerged. As part of this approach, selective fishing is widely encouraged in the belief that nonselective fishing has many adverse impacts. In particular, incidental bycatch is seen as wasteful and a negative feature of fishing, and methods to reduce bycatch are implemented in many fisheries. However, recent advances in fishery science and ecology suggest that a selective approach may also result in undesirable impacts both to fisheries and marine ecosystems. Selective fishing applies one or more of the "6-S" selections: species, stock, size, sex, season, and space. However, selective fishing alters biodiversity, which in turn changes ecosystem functioning and may affect fisheries production, hindering rather than helping achieve the goals of EBFM. We argue here that a "balanced exploitation" approach might alleviate many of the ecological effects of fishing by avoiding intensive removal of particular components of the ecosystem, while still supporting sustainable fisheries. This concept may require reducing exploitation rates on certain target species or groups to protect vulnerable components of the ecosystem. Benefits to society could be maintained or even increased because a greater proportion of the entire suite of harvested species is used.


Assuntos
Biodiversidade , Pesqueiros/métodos , Animais , Feminino , Peixes/crescimento & desenvolvimento , Masculino , Dinâmica Populacional , Estações do Ano
4.
PLoS One ; 18(3): e0282668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36921005

RESUMO

Production of cultivated resources require additional planning that takes growth time into account. We formulate a mathematical programming model to determine the optimal location and sizing of growth facilities, impacted by resource survival rate as a function of its growth time. Our method informs strategic decisions regarding the number, location, and sizing of facilities, as well as operational decisions of optimal growth time for a cultivated resource in a facility to minimize total costs. We solve this facility location and sizing problem in the context of coral aquaculture for large-scale reef restoration using a two-stage algorithm and a linear mixed-integer solver. We assess growth time in a facility in terms of its impact on survival (post-deployment) considering growth quantity requirements and growth facility production constraints. We explore the sensitivity of optimal facility number, location, and sizing to changes in the geographic distribution of demand and cost parameters computationally. Results show that the relationship between growth time and survival is critical to optimizing operational decisions for grown resources. These results inform the value of data certainty to optimize the logistics of coral aquaculture production.


Assuntos
Antozoários , Animais , Modelos Teóricos , Aquicultura
5.
Nature ; 440(7088): E8; discussion E9-10, 2006 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-16641948

RESUMO

Taubenberger et al. have sequenced the polymerase genes of the pandemic 'Spanish' influenza A virus of 1918, thereby completing the decoding of the genome of this virus. The authors conclude from these sequences that the virus jumped from birds to humans shortly before the start of the pandemic and that it was not derived from earlier viruses by gene shuffling, a process called reassortment. However, we believe that their evidence does not convincingly support these conclusions and that some of their results even indicate that, on the contrary, the virus evolved in mammals before the pandemic began and that it was a reassortant. In light of this alternative interpretation, we suggest that the current intense surveillance of influenza viruses should be broadened to include mammalian sources.


Assuntos
Aves/virologia , Evolução Molecular , Vírus da Influenza A Subtipo H1N1/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Filogenia , Animais , História do Século XX , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Aviária/transmissão , Influenza Humana/epidemiologia , Influenza Humana/história , Influenza Humana/transmissão , Modelos Biológicos , Vírus Reordenados/genética , Vírus Reordenados/fisiologia , Reprodutibilidade dos Testes , Suínos/virologia , Fatores de Tempo , Zoonoses/transmissão , Zoonoses/virologia
6.
PLoS One ; 17(11): e0273325, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36449458

RESUMO

While coral reefs in Australia have historically been a showcase of conventional management informed by research, recent declines in coral cover have triggered efforts to innovate and integrate intervention and restoration actions into management frameworks. Here we outline the multi-faceted intervention approaches that have developed in Australia since 2017, from newly implemented in-water programs, research to enhance coral resilience and investigations into socio-economic perspectives on restoration goals. We describe in-water projects using coral gardening, substrate stabilisation, coral repositioning, macro-algae removal, and larval-based restoration techniques. Three areas of research focus are also presented to illustrate the breadth of Australian research on coral restoration, (1) the transdisciplinary Reef Restoration and Adaptation Program (RRAP), one of the world's largest research and development programs focused on coral reefs, (2) interventions to enhance coral performance under climate change, and (3) research into socio-cultural perspectives. Together, these projects and the recent research focus reflect an increasing urgency for action to confront the coral reef crisis, develop new and additional tools to manage coral reefs, and the consequent increase in funding opportunities and management appetite for implementation. The rapid progress in trialling and deploying coral restoration in Australia builds on decades of overseas experience, and advances in research and development are showing positive signs that coral restoration can be a valuable tool to improve resilience at local scales (i.e., high early survival rates across a variety of methods and coral species, strong community engagement with local stakeholders). RRAP is focused on creating interventions to help coral reefs at multiple scales, from micro scales (i.e., interventions targeting small areas within a specific reef site) to large scales (i.e., interventions targeting core ecosystem function and social-economic values at multiple select sites across the Great Barrier Reef) to resist, adapt to and recover from the impacts of climate change. None of these interventions aim to single-handedly restore the entirety of the Great Barrier Reef, nor do they negate the importance of urgent climate change mitigation action.


Assuntos
Antozoários , Animais , Ecossistema , Austrália , Aclimatação , Água
8.
Risk Anal ; 31(11): 1784-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21449961

RESUMO

Ecological risk assessment embodied in an adaptive management framework is becoming the global standard approach for formally assessing and managing the ecological risks of technology and development. Ensuring the continual improvement of ecological risk assessment approaches is partly achieved through the dissemination of not only the types of risk assessment approaches used, but also their efficacy. While there is an increasing body of literature describing the results of general comparisons between alternate risk assessment methods and models, there is a paucity of literature that post hoc assesses the performance of specific predictions based on an assessment of risk and the effectiveness of the particular model used to predict the risk. This is especially the case where risk assessments have been used to grant consent or approval for the construction of major infrastructure projects. While postconstruction environmental monitoring is increasingly commonplace, it is not common for a postconstruction assessment of the accuracy and performance of the ecological risk assessment and underpinning model to be undertaken. Without this "assessment of the assessment," it is difficult for other practitioners to gain insight into the performance of the approach and models used and therefore, as argued here, this limits the rate of improvement of risk assessment approaches.


Assuntos
Ecologia , Medição de Risco , Meio Ambiente , Monitoramento Ambiental , Gestão de Riscos
9.
PLoS One ; 16(5): e0250870, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33956851

RESUMO

The health and condition of the world's reefs are in steep decline. This has triggered the development of fledgling micro-scale coral reef restoration projects along many reef coastlines. However, it is increasingly recognised that the scale and productivity of micro-scale coral gardening projects will be insufficient to meet the growing global threats to reefs. More recently, efforts to develop and implement restoration techniques for application at regional scales have been pursued by research organisations. Coral reefs are mostly located in the unindustrialised world. Yet, most of the funding, and scientific and engineering method development for larger-scale methods will likely be sourced and created in the industrialised world. Therefore, the development of the emerging at-scale global reef restoration sector will inevitably involve the transfer of methods, approaches, finances, labour and skills from the industrialised world to the unindustrialised world. This opens the door to the industrialised world negatively impacting the unindustrialised world and, in some cases, First Nations peoples. In Western scientific parlance, ecological imperialism occurs when people from industrialised nations seek to recreate environments and ecosystems in unindustrialised nations that are familiar and comfortable to them. How a coral reef 'should' look depends on one's background and perspective. While predominately Western scientific approaches provide guidance on the ecological principles for reef restoration, these methods might not be applicable in every scenario in unindustrialised nations. Imposing such views on Indigenous coastal communities without the local technical and leadership resources to scale-up restoration of their reefs can lead to unwanted consequences. The objective of this paper is to introduce this real and emerging risk into the broader reef restoration discussion.


Assuntos
Recifes de Corais , Ecologia/organização & administração , Recuperação e Remediação Ambiental/métodos , Internacionalidade , Colonialismo , Países Desenvolvidos , Países em Desenvolvimento
10.
Mol Phylogenet Evol ; 56(2): 526-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20434570

RESUMO

Influenza A virus infects a wide range of hosts including birds, humans, pigs, horses, and other mammals. Because hosts differ in immune system structure and demography, it is therefore expected that host populations leave different imprints on the viral genome. In this study, we investigated the evolutionary trajectory of the main lineages of N1 type neuraminidase (NA) gene sequences of influenza A viruses by estimating their evolutionary rates and the selection pressures exerted upon them. We also estimated the time of emergence of these lineages. The Eurasian (avian-like) and North American (classical) swine lineages, the human (seasonal) and avian H5N1 lineages, and a long persisting avian lineage were studied and compared. Nucleotide substitution rates ranged from 1.9x10(-3) to 4.3x10(-3) substitutions per site per year, with the H5N1 lineage estimated to have the greatest rate. The evolutionary rates of the H1N1 human lineage appeared to be slightly greater after it re-emerged in 1977 than before it disappeared in the 1950s. Comparing across the lineages, substitution rates appeared to correlate with the number of positively selected sites and with the degree of asymmetry of the phylogenetic trees. Some lineages had strongly asymmetric trees, implying repeated genotype replacement and narrow genetic diversity. Positively selected sites were identified in all lineages, with the H5N1 lineage having the largest number. A great number of isolates of the H5N1 lineage were sequenced in a short time period and the phylogeny of the lineage was more symmetric. We speculate that the rate and selection estimations made for this lineage could have been influenced by sampling and may not represent the long-term trends.


Assuntos
Evolução Molecular , Vírus da Influenza A/genética , Neuraminidase/genética , Seleção Genética , Análise por Conglomerados , Genótipo , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/genética , Virus da Influenza A Subtipo H5N1/enzimologia , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A/classificação , Vírus da Influenza A/enzimologia , Funções Verossimilhança , Filogenia , RNA Viral/genética
11.
Biomimetics (Basel) ; 5(2)2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32443598

RESUMO

Amidst the inter-related challenges of climate change, resource scarcity, and population growth, the built environment must be designed in a way that recognises its role in shaping and being shaped by complex social and ecological systems. This includes avoiding the degradation of living systems in the design and construction of buildings and infrastructure, as well as enhancing the built environment's resilience to disturbance by those systems. This paper explores the potential for biomimetic place-based design (BPD) to inform resilient and regenerative built environment outcomes by learning from local ecosystems. One recognised hurdle is the upfront resourcing required to establish the biomimetic knowledge base for each project. However, conducting BPD projects at-scale (i.e., city or region) can improve the method's value-proposition by better leveraging upfront research efforts, design concepts, and strategies. This research identifies existing barriers to the widespread adoption of BPD and presents an action framework for capability-building across industry, government, and academia to enable application at-scale. Drawing on findings from workshops in the USA and Australia, it creates a resource for colleagues looking to apply BPD in a city or region and offers next steps for research and development.

12.
PLoS One ; 15(10): e0240846, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33108387

RESUMO

Coral reef ecosystems are under increasing pressure from local and regional stressors and a changing climate. Current management focuses on reducing stressors to allow for natural recovery, but in many areas where coral reefs are damaged, natural recovery can be restricted, delayed or interrupted because of unstable, unconsolidated coral fragments, or rubble. Rubble fields are a natural component of coral reefs, but repeated or high-magnitude disturbances can prevent natural cementation and consolidation processes, so that coral recruits fail to survive. A suite of interventions have been used to target this issue globally, such as using mesh to stabilise rubble, removing the rubble to reveal hard substrate and deploying rocks or other hard substrates over the rubble to facilitate recruit survival. Small, modular structures can be used at multiple scales, with or without attached coral fragments, to create structural complexity and settlement surfaces. However, these can introduce foreign materials to the reef, and a limited understanding of natural recovery processes exists for the potential of this type of active intervention to successfully restore local coral reef structure. This review synthesises available knowledge about the ecological role of coral rubble, natural coral recolonisation and recovery rates and the potential benefits and risks associated with active interventions in this rapidly evolving field. Fundamental knowledge gaps include baseline levels of rubble, the structural complexity of reef habitats in space and time, natural rubble consolidation processes and the risks associated with each intervention method. Any restoration intervention needs to be underpinned by risk assessment, and the decision to repair rubble fields must arise from an understanding of when and where unconsolidated substrate and lack of structure impair natural reef recovery and ecological function. Monitoring is necessary to ascertain the success or failure of the intervention and impacts of potential risks, but there is a strong need to specify desired outcomes, the spatial and temporal context and indicators to be measured. With a focus on the Great Barrier Reef, we synthesise the techniques, successes and failures associated with rubble stabilisation and the use of small structures, review monitoring methods and indicators, and provide recommendations to ensure that we learn from past projects.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Animais , Antozoários , Biodiversidade , Conservação dos Recursos Naturais/métodos , Monitorização de Parâmetros Ecológicos/métodos , Ecossistema , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos
13.
Biomimetics (Basel) ; 4(4)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683928

RESUMO

Complex systems challenges like those facing 21st-century humanity, require system-level solutions that avoid siloed or unnecessarily narrow responses. System-level biomimicry aims to identify and adopt design approaches that have been developed and refined within ecosystems over 3.8 billion years of evolution. While not new, system-level biomimetic solutions have been less widely applied in urban design than the 'form' and 'process' level counterparts. This paper explores insights from a selection of system-level case studies in the built environment, using meta-analysis to investigate common challenges and priorities from these projects to support knowledge-sharing and continued development in the field. Using a grounded research approach, common themes are distilled, and findings presented regarding success and barriers to implementation and scaling. Considering the findings, and drawing on complex adaptive systems theory, the paper posits opportunities to facilitate broader implementation and mainstreaming of system-level biomimetic design approaches in the built environment.

14.
Viruses ; 11(11)2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31698821

RESUMO

Analyses of pospiviroids in commercial seed lots of tomato and capsicum, determined by testing of 12,000 to 40,000 seeds per lot, have enabled the development of empirically-derived distribution curves for the observed prevalences of viroids in those commodities. Those distribution curves can be considered in conjunction with statistically-based estimates of detection that would be achieved using other sample sizes. Statistical calculations using binomial distributions show that sample sizes of 3000 and 9400 seeds allow detection of viroid prevalences as low as 0.1% and 0.032%, respectively, with 95% confidence. Applying those calculations to observed viroid prevalences in contaminated tomato seed lots, it is estimated that the use of sample sizes of 3000 and 9400 seeds would detect 15% and 42%, respectively, of the contaminated seed lots identified using the larger sample sizes of approximately 20,000 seeds reported in this study. It is concluded that the higher costs associated with testing of larger sample sizes represent a worthwhile investment in agricultural biosecurity.


Assuntos
Capsicum/virologia , Sementes/virologia , Solanum lycopersicum/virologia , Viroides , Proteção de Cultivos , Patologia Molecular , Doenças das Plantas/virologia , Prevalência , RNA Viral , Viroides/genética , Viroides/isolamento & purificação
15.
Viruses ; 11(2)2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682856

RESUMO

Pospiviroid species are transmitted through capsicum and tomato seeds. Trade in these seeds represents a route for the viroids to invade new regions, but the magnitude of this hazard has not been adequately investigated. Since 2012, tomato seed lots sent to Australia have been tested for pospiviroids before they are released from border quarantine, and capsicum seed lots have been similarly tested in quarantine since 2013. Altogether, more than 2000 seed lots have been tested. Pospiviroids were detected in more than 10% of the seed lots in the first years of mandatory testing, but the proportion of lots that were infected declined in subsequent years to less than 5%. Six pospiviroid species were detected: Citrus exocortis viroid, Columnea latent viroid, Pepper chat fruit viroid, Potato spindle tuber viroid, Tomato chlorotic dwarf viroid and Tomato apical stunt viroid. They were detected in seed lots exported from 18 countries from every production region. In many seed lots, the detectable fraction (prevalence) of infected seeds was estimated to be very small, as low as 6 × 10-5 (~1 in 16,000; CI 5 × 10-6 to 2.5 × 10-4) for some lots. These findings raise questions about seed production practices, and the study indicates the geographic distributions of these pathogens are uncertain, and there is a continuing threat of invasion.


Assuntos
Capsicum/virologia , Sementes/virologia , Solanum lycopersicum/virologia , Viroides/isolamento & purificação , Austrália , Comércio , Filogenia , Doenças das Plantas/virologia , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , RNA Viral , Meios de Transporte , Viroides/genética
16.
BMC Bioinformatics ; 9: 83, 2008 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-18251994

RESUMO

BACKGROUND: Viruses of the Bunyaviridae have segmented negative-stranded RNA genomes and several of them cause significant disease. Many partial sequences have been obtained from the segments so that GenBank searches give complex results. Sequence databases usually use HTML pages to mediate remote sorting, but this approach can be limiting and may discourage a user from exploring a database. RESULTS: The VirusBanker database contains Bunyaviridae sequences and alignments and is presented as two spreadsheets generated by a Java program that interacts with a MySQL database on a server. Sequences are displayed in rows and may be sorted using information that is displayed in columns and includes data relating to the segment, gene, protein, species, strain, sequence length, terminal sequence and date and country of isolation. Bunyaviridae sequences and alignments may be downloaded from the second spreadsheet with titles defined by the user from the columns, or viewed when passed directly to the sequence editor, Jalview. CONCLUSION: VirusBanker allows large datasets of aligned nucleotide and protein sequences from the Bunyaviridae to be compiled and winnowed rapidly using criteria that are formulated heuristically.


Assuntos
Bunyaviridae/química , Bunyaviridae/genética , Bases de Dados Genéticas , Sistemas de Informação , Software , Sequência de Bases , Sistemas de Gerenciamento de Base de Dados/tendências , Bases de Dados Genéticas/tendências , Sistemas de Informação/tendências , Dados de Sequência Molecular , Análise de Sequência de Proteína/métodos , Análise de Sequência de Proteína/tendências , Software/tendências
17.
Virol J ; 5: 16, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18218114

RESUMO

BACKGROUND: Species within the Flavivirus genus pose public health problems around the world. Increasing cases of Dengue and Japanese encephalitis virus in Asia, frequent outbreaks of Yellow fever virus in Africa and South America, and the ongoing spread of West Nile virus throughout the Americas, show the geographical burden of flavivirus diseases. Flavivirus infections are often indistinct from and confused with other febrile illnesses. Here we review the specificity of published primers, and describe a new universal primer pair that can detect a wide range of flaviviruses, including viruses from each of the recognised subgroups. RESULTS: Bioinformatic analysis of 257 published full-length Flavivirus genomes revealed conserved regions not previously targeted by primers. Two degenerate primers, Flav100F and Flav200R were designed from these regions and used to generate an 800 base pair cDNA product. The region amplified encoded part of the methyltransferase and most of the RNA-dependent-RNA-polymerase (NS5) coding sequence. One-step RT-PCR testing was successful using standard conditions with RNA from over 60 different flavivirus strains representing about 50 species. The cDNA from each virus isolate was sequenced then used in phylogenetic analyses and database searches to confirm the identity of the template RNA. CONCLUSION: Comprehensive testing has revealed the broad specificity of these primers. We briefly discuss the advantages and uses of these universal primers.


Assuntos
Primers do DNA , Flavivirus/genética , Técnicas de Amplificação de Ácido Nucleico , RNA Viral/biossíntese , Animais , Sequência Conservada , Flavivirus/classificação , Infecções por Flavivirus/diagnóstico , Infecções por Flavivirus/virologia , Humanos , RNA Viral/genética , Proteínas não Estruturais Virais/genética
18.
J Virol Methods ; 153(2): 97-103, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18760305

RESUMO

Polymerase chain reaction (PCR) is used to detect groups of viruses with the use of group-specific degenerate primers. Inosine residues are sometimes used in the primers to match variable positions within the complementary target sequences, but there is little data on their effects on cDNA synthesis and amplification. A quantitative reverse-transcription PCR was used to measure the rate of amplification with primers containing inosine residues substituted at different positions and in increasing numbers. Experiments were conducted using standard quantities of cloned DNA copied from Potato virus Y genomic RNA and RNA (cRNA) transcribed from the cloned DNA. Single inosine residues had no affect on the amplification rate in the forward primer, except at one position close to the 3' terminus. Conversely, single inosine residues significantly reduced the amplification rate when placed at three out of four positions in the reverse primer. Four or five inosine substitutions could be tolerated with some decline in rates, but amplification often failed from cRNA templates with primers containing larger numbers of inosines. Greater declines in the rate of amplification were observed with RNA templates, suggesting that reverse transcription suffers more than PCR amplification when inosine is included in the reverse primer.


Assuntos
Primers do DNA , Inosina/química , Reação em Cadeia da Polimerase/métodos , Potyvirus/genética , RNA Viral , Benzotiazóis , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/metabolismo , Diaminas , Compostos Orgânicos , Doenças das Plantas/virologia , Folhas de Planta/virologia , Potyvirus/isolamento & purificação , Quinolinas , RNA Complementar/química , RNA Complementar/genética , RNA Complementar/metabolismo , RNA Viral/análise , RNA Viral/química , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Solanum tuberosum/virologia , Moldes Genéticos
19.
J Virol Methods ; 152(1-2): 98-101, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18602951

RESUMO

We describe a simple Perl computer tool for matching successive subsequences of a query sequence using the BLAST facilities of Genbank. SWeBLAST helps identify 'parents' of recombinant sequences, even when these are themselves unrelated, thus it is complementary to methods that compare sets of aligned homologous sequences, and avoids the significant problem of these methods in having first to decide which sequences to compare. SWeBLAST searches may also be valuable for checking the recombination history of genes proposed for use as transgenes.


Assuntos
Biologia Computacional/métodos , Internet , Alinhamento de Sequência/métodos , Software , Filogenia , Potyvirus/classificação , Potyvirus/genética , Análise de Sequência/métodos , Interface Usuário-Computador
20.
Sci China C Life Sci ; 51(11): 987-93, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18989641

RESUMO

We investigated the selection pressures on the haemagglutinin genes of H5N1 avian influenza viruses using fixed effects likelihood models. We found evidence of positive selection in the sequences from isolates from 1997 to 2007, except viruses from 2000. The haemagglutinin sequences of viruses from southeast Asia, Hong Kong and mainland China were the most polymorphic and had similar nonsynonymous profiles. Some sites were positively selected in viruses from most regions and a few of these sites displayed different amino acid patterns. Selection appeared to produce different outcomes in viruses from Europe, Africa and Russia and from different host types. One position was found to be positively selected for human isolates only. Although the functions of some positively selected positions are unknown, our analysis provided evidence of different temporal, spatial and host adaptations for H5N1 avian influenza viruses.


Assuntos
Genes Virais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/genética , Animais , Aves , Códon , Bases de Dados Genéticas , Variação Genética , Humanos , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/virologia , Influenza Humana/virologia , Funções Verossimilhança , Mamíferos , Modelos Genéticos , Infecções por Orthomyxoviridae/virologia , Seleção Genética , Especificidade da Espécie
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