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Peter Simmonds

Bio: Peter Simmonds is an academic researcher from University of Oxford. The author has contributed to research in topics: Hepatitis C virus & Virus. The author has an hindex of 131, co-authored 823 publications receiving 62953 citations. Previous affiliations of Peter Simmonds include John Radcliffe Hospital & Edinburgh Royal Infirmary.
Topics: Hepatitis C virus, Virus, Hepatitis C, Population, RNA


Papers
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Journal ArticleDOI
TL;DR: A new nomenclature for HCV variants is proposed in this communication that reflects the two-tiered nature of sequence differences between different viral isolates and describes criteria that would enable new variants to be assigned within the classification as they are discovered.
Abstract: Hepatitis C virus (HCV) showed substantial nucleotide sequence diversity distributed throughout the viral genome, with many variants showing only 68 to 79% overall sequence similarity to one another. Phylogenetic analysis of nucleotide sequences derived from part of the gene encoding a non-structural protein (NS-5) has provided evidence for six major genotypes of HCV amongst a worldwide collection of 76 samples from HCV-infected blood donors and patients with chronic hepatitis. Many of these HCV types comprised a number of more closely related subtypes, leading to a current total of 11 genetically distinct viral populations. Phylogenetic analysis of other regions of the viral genome produced relationships between published sequences equivalent to those found in NS-5, apart from the more highly conserved 5' non-coding region in which only the six major HCV types, but not subtypes, could be differentiated. A new nomenclature for HCV variants is proposed in this communication that reflects the two-tiered nature of sequence differences between different viral isolates. The scheme classifies all known HCV variants to date, and describes criteria that would enable new variants to be assigned within the classification as they are discovered.

1,424 citations

Journal ArticleDOI
TL;DR: This study represents a major update to the previous consensus HCV classification, incorporating additional sequence information derived from over 1,300 (near‐)complete genome sequences of HCV available on public databases in May 2013.

1,219 citations

Journal ArticleDOI
TL;DR: Changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses in February 2015 are listed.
Abstract: Changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses in February 2015 are listed.

1,039 citations


Cited by
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01 Jun 2012
TL;DR: SPAdes as mentioned in this paper is a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler and on popular assemblers Velvet and SoapDeNovo (for multicell data).
Abstract: The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.

10,124 citations

Journal ArticleDOI
TL;DR: The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity, and molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth.
Abstract: This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

7,638 citations

Journal ArticleDOI
TL;DR: In this article, a review of available scientific evidence shows that human alterations of the nitrogen cycle have approximately doubled the rate of nitrogen input into the terrestrial nitrogen cycle, with these rates still increasing; increased concentrations of the potent greenhouse gas N 2O globally, and increased concentration of other oxides of nitrogen that drive the formation of photochemical smog over large regions of Earth.
Abstract: Nitrogen is a key element controlling the species composition, diversity, dynamics, and functioning of many terrestrial, freshwater, and marine ecosystems. Many of the original plant species living in these ecosystems are adapted to, and function optimally in, soils and solutions with low levels of available nitrogen. The growth and dynamics of herbivore populations, and ultimately those of their predators, also are affected by N. Agriculture, combustion of fossil fuels, and other human activities have altered the global cycle of N substantially, generally increasing both the availability and the mobility of N over large regions of Earth. The mobility of N means that while most deliberate applications of N occur locally, their influence spreads regionally and even globally. Moreover, many of the mobile forms of N themselves have environmental consequences. Although most nitrogen inputs serve human needs such as agricultural production, their environmental conse- quences are serious and long term. Based on our review of available scientific evidence, we are certain that human alterations of the nitrogen cycle have: 1) approximately doubled the rate of nitrogen input into the terrestrial nitrogen cycle, with these rates still increasing; 2) increased concentrations of the potent greenhouse gas N 2O globally, and increased concentrations of other oxides of nitrogen that drive the formation of photochemical smog over large regions of Earth; 3) caused losses of soil nutrients, such as calcium and potassium, that are essential for the long-term maintenance of soil fertility; 4) contributed substantially to the acidification of soils, streams, and lakes in several regions; and 5) greatly increased the transfer of nitrogen through rivers to estuaries and coastal oceans. In addition, based on our review of available scientific evidence we are confident that human alterations of the nitrogen cycle have: 6) increased the quantity of organic carbon stored within terrestrial ecosystems; 7) accelerated losses of biological diversity, especially losses of plants adapted to efficient use of nitrogen, and losses of the animals and microorganisms that depend on them; and 8) caused changes in the composition and functioning of estuarine and nearshore ecosystems, and contributed to long-term declines in coastal marine fisheries.

5,729 citations

Journal ArticleDOI
TL;DR: The independent zoonotic transmission of SARS-CoV and SARS -CoV-2 highlights the need for studying viruses at the species level to complement research focused on individual pathogenic viruses of immediate significance.
Abstract: The present outbreak of a coronavirus-associated acute respiratory disease called coronavirus disease 19 (COVID-19) is the third documented spillover of an animal coronavirus to humans in only two decades that has resulted in a major epidemic. The Coronaviridae Study Group (CSG) of the International Committee on Taxonomy of Viruses, which is responsible for developing the classification of viruses and taxon nomenclature of the family Coronaviridae, has assessed the placement of the human pathogen, tentatively named 2019-nCoV, within the Coronaviridae. Based on phylogeny, taxonomy and established practice, the CSG recognizes this virus as forming a sister clade to the prototype human and bat severe acute respiratory syndrome coronaviruses (SARS-CoVs) of the species Severe acute respiratory syndrome-related coronavirus, and designates it as SARS-CoV-2. In order to facilitate communication, the CSG proposes to use the following naming convention for individual isolates: SARS-CoV-2/host/location/isolate/date. While the full spectrum of clinical manifestations associated with SARS-CoV-2 infections in humans remains to be determined, the independent zoonotic transmission of SARS-CoV and SARS-CoV-2 highlights the need for studying viruses at the species level to complement research focused on individual pathogenic viruses of immediate significance. This will improve our understanding of virus–host interactions in an ever-changing environment and enhance our preparedness for future outbreaks.

5,527 citations