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Université de Perpignan

UniversityPerpignan, Occitanie, France

Research output, citation impact, and the most-cited recent papers from Université de Perpignan (France). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
15.8K
Citations
628.4K
h-index
271
i10-index
10.3K
Also known as
Universitat de Perpinyà Via DomitiaUniversitat de Perpinyà Via DomíciaUniversity of PerpignanUniversité de Perpignan

Top-cited papers from Université de Perpignan

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)
Daniel J. Klionsky, Kotb Abdelmohsen, Akihisa Abe, Md. Joynal Abedin +4 more
2016· Autophagy6.0Kdoi:10.1080/15548627.2015.1100356

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is thatthere is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure flux through the autophagy pathway (i.e., the completeprocess including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defined as increasedautophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in manycases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as forreviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multipleassays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation, it is imperative to target by gene knockout or RNA interference more than one autophagyrelated protein. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways implying that not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular assays, we hope to encourage technical innovation in the field.

The B73 Maize Genome: Complexity, Diversity, and Dynamics
Patrick S. Schnable, Doreen Ware, Robert S. Fulton, Joshua C. Stein +4 more
2009· Science4.2Kdoi:10.1126/science.1178534

A-Maize-ing Maize is one of our oldest and most important crops, having been domesticated approximately 9000 years ago in central Mexico. Schnable et al. (p. 1112 ; see the cover) present the results of sequencing the B73 inbred maize line. The findings elucidate how maize became diploid after an ancestral doubling of its chromosomes and reveals transposable element movement and activity and recombination. Vielle-Calzada et al. (p. 1078 ) have sequenced the Palomero Toluqueño ( Palomero ) landrace, a highland popcorn from Mexico, which, when compared to the B73 line, reveals multiple loci impacted by domestication. Swanson-Wagner et al. (p. 1118 ) exploit possession of the genome to analyze expression differences occurring between lines. The identification of single nucleotide polymorphisms and copy number variations among lines was used by Gore et al. (p. 1115 ) to generate a Haplotype map of maize. While chromosomal diversity in maize is high, it is likely that recombination is the major force affecting the levels of heterozygosity in maize. The availability of the maize genome will help to guide future agricultural and biofuel applications (see the Perspective by Feuillet and Eversole ).

A new versatile primer set targeting a short fragment of the mitochondrial COI region for metabarcoding metazoan diversity: application for characterizing coral reef fish gut contents
Matthieu Leray, Joy Yang, Chris Meyer, Suzanne C. Mills +4 more
2013· Frontiers in Zoology1.7Kdoi:10.1186/1742-9994-10-34

INTRODUCTION: The PCR-based analysis of homologous genes has become one of the most powerful approaches for species detection and identification, particularly with the recent availability of Next Generation Sequencing platforms (NGS) making it possible to identify species composition from a broad range of environmental samples. Identifying species from these samples relies on the ability to match sequences with reference barcodes for taxonomic identification. Unfortunately, most studies of environmental samples have targeted ribosomal markers, despite the fact that the mitochondrial Cytochrome c Oxidase subunit I gene (COI) is by far the most widely available sequence region in public reference libraries. This is largely because the available versatile ("universal") COI primers target the 658 barcoding region, whose size is considered too large for many NGS applications. Moreover, traditional barcoding primers are known to be poorly conserved across some taxonomic groups. RESULTS: We first design a new PCR primer within the highly variable mitochondrial COI region, the "mlCOIintF" primer. We then show that this newly designed forward primer combined with the "jgHCO2198" reverse primer to target a 313 bp fragment performs well across metazoan diversity, with higher success rates than versatile primer sets traditionally used for DNA barcoding (i.e. LCO1490/HCO2198). Finally, we demonstrate how the shorter COI fragment coupled with an efficient bioinformatics pipeline can be used to characterize species diversity from environmental samples by pyrosequencing. We examine the gut contents of three species of planktivorous and benthivorous coral reef fish (family: Apogonidae and Holocentridae). After the removal of dubious COI sequences, we obtained a total of 334 prey Operational Taxonomic Units (OTUs) belonging to 14 phyla from 16 fish guts. Of these, 52.5% matched a reference barcode (>98% sequence similarity) and an additional 32% could be assigned to a higher taxonomic level using Bayesian assignment. CONCLUSIONS: The molecular analysis of gut contents targeting the 313 COI fragment using the newly designed mlCOIintF primer in combination with the jgHCO2198 primer offers enormous promise for metazoan metabarcoding studies. We believe that this primer set will be a valuable asset for a range of applications from large-scale biodiversity assessments to food web studies.

Reference genome sequence of the model plant Setaria
Jeffrey L. Bennetzen, Jeremy Schmutz, Hao Wang, Ryan Percifield +4 more
2012· Nature Biotechnology989doi:10.1038/nbt.2196

Completion of genome sequences for the diploid Setaria italica reveals features of C4 photosynthesis that could enable improvement of the polyploid biofuel crop switchgrass (Panicum virgatum). The genetic basis of biotechnologically relevant traits, including drought tolerance, photosynthetic efficiency and flowering control, is also highlighted. We generated a high-quality reference genome sequence for foxtail millet (Setaria italica). The ∼400-Mb assembly covers ∼80% of the genome and >95% of the gene space. The assembly was anchored to a 992-locus genetic map and was annotated by comparison with >1.3 million expressed sequence tag reads. We produced more than 580 million RNA-Seq reads to facilitate expression analyses. We also sequenced Setaria viridis, the ancestral wild relative of S. italica, and identified regions of differential single-nucleotide polymorphism density, distribution of transposable elements, small RNA content, chromosomal rearrangement and segregation distortion. The genus Setaria includes natural and cultivated species that demonstrate a wide capacity for adaptation. The genetic basis of this adaptation was investigated by comparing five sequenced grass genomes. We also used the diploid Setaria genome to evaluate the ongoing genome assembly of a related polyploid, switchgrass (Panicum virgatum).

The One Health Concept: 10 Years Old and a Long Road Ahead
Delphine Destoumieux‐Garzón, Patrick Mavingui, Gilles Boëtsch, Jérôme Boissier +4 more
2018· Frontiers in Veterinary Science895doi:10.3389/fvets.2018.00014

Over the past decade, a significant increase in the circulation of infectious agents was observed. With the spread and emergence of epizootics, zoonoses, and epidemics, the risks of pandemics became more and more critical. Human and animal health has also been threatened by antimicrobial resistance, environmental pollution, and the development of multifactorial and chronic diseases. This highlighted the increasing globalization of health risks and the importance of the human-animal-ecosystem interface in the evolution and emergence of pathogens. A better knowledge of causes and consequences of certain human activities, lifestyles, and behaviors in ecosystems is crucial for a rigorous interpretation of disease dynamics and to drive public policies. As a global good, health security must be understood on a global scale and from a global and crosscutting perspective, integrating human health, animal health, plant health, ecosystems health, and biodiversity. In this study, we discuss how crucial it is to consider ecological, evolutionary, and environmental sciences in understanding the emergence and re-emergence of infectious diseases and in facing the challenges of antimicrobial resistance. We also discuss the application of the "One Health" concept to non-communicable chronic diseases linked to exposure to multiple stresses, including toxic stress, and new lifestyles. Finally, we draw up a list of barriers that need removing and the ambitions that we must nurture for the effective application of the "One Health" concept. We conclude that the success of this One Health concept now requires breaking down the interdisciplinary barriers that still separate human and veterinary medicine from ecological, evolutionary, and environmental sciences. The development of integrative approaches should be promoted by linking the study of factors underlying stress responses to their consequences on ecosystem functioning and evolution. This knowledge is required for the development of novel control strategies inspired by environmental mechanisms leading to desired equilibrium and dynamics in healthy ecosystems and must provide in the near future a framework for more integrated operational initiatives.

A global outlook to the interruption of education due to COVID-19 pandemic: Navigating in a time of uncertainty and crisis
Aras Bozkurt, Insung Jung, Junhong Xiao, Viviane Vladimirschi +4 more
2020· UniSA Research Outputs Repository (University of South Australia)880doi:10.5281/zenodo.3878572

Uncertain times require prompt reflexes to survive and this study is a collaborative reflex to better understand uncertainty and navigate through it. The Coronavirus (Covid-19) pandemic hit hard and interrupted many dimensions of our lives, particularly education. As a response to interruption of education due to the Covid-19 pandemic, this study is a collaborative reaction that narrates the overall view, reflections from the K12 and higher educational landscape, lessons learned and suggestions from a total of 31 countries across the world with a representation of 62.7% of the whole world population. In addition to the value of each case by country, the synthesis of this research suggests that the current practices can be defined as emergency remote education and this practice is different from planned practices such as distance education, online learning or other derivations. Above all, this study points out how social injustice, inequity and the digital divide have been exacerbated during the pandemic and need unique and targeted measures if they are to be addressed. While there are support communities and mechanisms, parents are overburdened between regular daily/professional duties and emerging educational roles, and all parties are experiencing trauma, psychological pressure and anxiety to various degrees, which necessitates a pedagogy of care, affection and empathy. In terms of educational processes, the interruption of education signifies the importance of openness in education and highlights issues that should be taken into consideration such as using alternative assessment and evaluation methods as well as concerns about surveillance, ethics, and data privacy resulting from nearly exclusive dependency on online solutions.

Genome analysis of the smallest free-living eukaryote <i>Ostreococcus tauri</i> unveils many unique features
Évelyne Derelle, Conchita Ferraz, Stéphane Rombauts, Pierre Rouzé +4 more
2006· Proceedings of the National Academy of Sciences868doi:10.1073/pnas.0604795103

The green lineage is reportedly 1,500 million years old, evolving shortly after the endosymbiosis event that gave rise to early photosynthetic eukaryotes. In this study, we unveil the complete genome sequence of an ancient member of this lineage, the unicellular green alga Ostreococcus tauri (Prasinophyceae). This cosmopolitan marine primary producer is the world's smallest free-living eukaryote known to date. Features likely reflecting optimization of environmentally relevant pathways, including resource acquisition, unusual photosynthesis apparatus, and genes potentially involved in C(4) photosynthesis, were observed, as was downsizing of many gene families. Overall, the 12.56-Mb nuclear genome has an extremely high gene density, in part because of extensive reduction of intergenic regions and other forms of compaction such as gene fusion. However, the genome is structurally complex. It exhibits previously unobserved levels of heterogeneity for a eukaryote. Two chromosomes differ structurally from the other eighteen. Both have a significantly biased G+C content, and, remarkably, they contain the majority of transposable elements. Many chromosome 2 genes also have unique codon usage and splicing, but phylogenetic analysis and composition do not support alien gene origin. In contrast, most chromosome 19 genes show no similarity to green lineage genes and a large number of them are specialized in cell surface processes. Taken together, the complete genome sequence, unusual features, and downsized gene families, make O. tauri an ideal model system for research on eukaryotic genome evolution, including chromosome specialization and green lineage ancestry.

The genome sequence of segmental allotetraploid peanut Arachis hypogaea
David J. Bertioli, Jerry Jenkins, Josh Clevenger, Olga Dudchenko +4 more
2019· Nature Genetics831doi:10.1038/s41588-019-0405-z

Like many other crops, the cultivated peanut (Arachis hypogaea L.) is of hybrid origin and has a polyploid genome that contains essentially complete sets of chromosomes from two ancestral species. Here we report the genome sequence of peanut and show that after its polyploid origin, the genome has evolved through mobile-element activity, deletions and by the flow of genetic information between corresponding ancestral chromosomes (that is, homeologous recombination). Uniformity of patterns of homeologous recombination at the ends of chromosomes favors a single origin for cultivated peanut and its wild counterpart A. monticola. However, through much of the genome, homeologous recombination has created diversity. Using new polyploid hybrids made from the ancestral species, we show how this can generate phenotypic changes such as spontaneous changes in the color of the flowers. We suggest that diversity generated by these genetic mechanisms helped to favor the domestication of the polyploid A. hypogaea over other diploid Arachis species cultivated by humans.

The genome of Theobroma cacao
Xavier Argout, Jérôme Salse, Jean‐Marc Aury, Mark J. Guiltinan +4 more
2010· Nature Genetics779doi:10.1038/ng.736

Xavier Argout and colleagues report the draft genome of Theobroma cacao, the tropical crop that is the source of chocolate. The sequence assembly covers approximately 80% of the genome. We sequenced and assembled the draft genome of Theobroma cacao, an economically important tropical-fruit tree crop that is the source of chocolate. This assembly corresponds to 76% of the estimated genome size and contains almost all previously described genes, with 82% of these genes anchored on the 10 T. cacao chromosomes. Analysis of this sequence information highlighted specific expansion of some gene families during evolution, for example, flavonoid-related genes. It also provides a major source of candidate genes for T. cacao improvement. Based on the inferred paleohistory of the T. cacao genome, we propose an evolutionary scenario whereby the ten T. cacao chromosomes were shaped from an ancestor through eleven chromosome fusions.

Biological nitrogen fixation in non-legume plants
Carole Santi, Didier Bogusz, Claudine Franche
2013· Annals of Botany776doi:10.1093/aob/mct048

BACKGROUND: Nitrogen is an essential nutrient in plant growth. The ability of a plant to supply all or part of its requirements from biological nitrogen fixation (BNF) thanks to interactions with endosymbiotic, associative and endophytic symbionts, confers a great competitive advantage over non-nitrogen-fixing plants. SCOPE: Because BNF in legumes is well documented, this review focuses on BNF in non-legume plants. Despite the phylogenic and ecological diversity among diazotrophic bacteria and their hosts, tightly regulated communication is always necessary between the microorganisms and the host plant to achieve a successful interaction. Ongoing research efforts to improve knowledge of the molecular mechanisms underlying these original relationships and some common strategies leading to a successful relationship between the nitrogen-fixing microorganisms and their hosts are presented. CONCLUSIONS: Understanding the molecular mechanism of BNF outside the legume-rhizobium symbiosis could have important agronomic implications and enable the use of N-fertilizers to be reduced or even avoided. Indeed, in the short term, improved understanding could lead to more sustainable exploitation of the biodiversity of nitrogen-fixing organisms and, in the longer term, to the transfer of endosymbiotic nitrogen-fixation capacities to major non-legume crops.

Forced Regressions in a Sequence Stratigraphic Framework: Concepts, Examples, and Exploration Significance
Henry W. Posamentier, George P. Allen, David P. James, Michel Tesson
1992· AAPG Bulletin741doi:10.1306/bdff8aa6-1718-11d7-8645000102c1865d

ABSTRACT Sequence stratigraphic concepts suggest that stratal geometries develop and are largely controlled by changes in relative sea level. On the shelf, lowstand deposits, which form during falls and subsequent stillstands of relative sea level, can be recognized by the presence of an unconformity at the base, the isolated and basinward position relative to the previous shoreline, and the abrupt seaward translation of shallow-water and shoreline facies into the basin across an unconformity surface. This seaward translation of facies and shoreline regression in response to relative sea level lowering is termed a “forced regression.” A forced regression is independent of variations of sediment flux and is in contrast with “normal” regressions that occur in response to excess sediment flux relative to space available on the shelf (i.e., accommodation). Forced regressions commonly are associated with a zone of sedimentary bypass, subaerial exposure, and possible fluvial erosion between the newly formed and preceding shorelines. Certain shelf sands, previously interpreted as offshore or mid-shelf sand bodies, thus can be reinterpreted as stranded lowstand shorelines associated with forced regressions. This alternative interpretation has economic significance insofar as it suggests different subsurface correlations and reservoir geometries with the potential for development of new play types and enhanced recovery in older fields. Examples of forced regression can be observed at a variety of scales and ages. Several such examples include the modern East Coulee fan delta and the Lower Cretaceous Viking Formation in Alberta, Canada, the Quaternary Rhône Delta, and the Quaternary Hudson Valley system.

A multi-decade record of high-quality <i>f</i> CO <sub>2</sub> data in version 3 of the Surface Ocean CO <sub>2</sub> Atlas (SOCAT)
Dorothée C. E. Bakker, Benjamin Pfeil, Camilla S. Landa, Nicolas Metzl +4 more
2016· Earth system science data714doi:10.5194/essd-8-383-2016

Abstract. The Surface Ocean CO2 Atlas (SOCAT) is a synthesis of quality-controlled fCO2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million fCO2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million fCO2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water fCO2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water fCO2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) "living data" publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014). Individual data set files, included in the synthesis product, can be downloaded here: doi:10.1594/PANGAEA.849770. The gridded products are available here: doi:10.3334/CDIAC/OTG.SOCAT_V3_GRID.

A global outlook to the interruption of education due to COVID-19 pandemic: Navigating in a time of uncertainty and crisis
Aras Bozkurt, Insung Jung, Junhong Xiao, Viviane Vladimirschi +4 more
2020· Acta Académica (Acta Académica)676doi:10.5281/zenodo.3878571

Uncertain times require prompt reflexes to survive and this study is a collaborative reflex to better understand uncertainty and navigate through it. The Coronavirus (Covid-19) pandemic hit hard and interrupted many dimensions of our lives, particularly education. As a response to interruption of education due to the Covid-19 pandemic, this study is a collaborative reaction that narrates the overall view, reflections from the K12 and higher educational landscape, lessons learned and suggestions from a total of 31 countries across the world with a representation of 62.7% of the whole world population. In addition to the value of each case by country, the synthesis of this research suggests that the current practices can be defined as emergency remote education and this practice is different from planned practices such as distance education, online learning or other derivations. Above all, this study points out how social injustice, inequity and the digital divide have been exacerbated during the pandemic and need unique and targeted measures if they are to be addressed. While there are support communities and mechanisms, parents are overburdened between regular daily/professional duties and emerging educational roles, and all parties are experiencing trauma, psychological pressure and anxiety to various degrees, which necessitates a pedagogy of care, affection and empathy. In terms of educational processes, the interruption of education signifies the importance of openness in education and highlights issues that should be taken into consideration such as using alternative assessment and evaluation methods as well as concerns about surveillance, ethics, and data privacy resulting from nearly exclusive dependency on online solutions.

Quality Assessment of the French OpenStreetMap Dataset
Jean‐François Girres, Guillaume Touya
2010· Transactions in GIS673doi:10.1111/j.1467-9671.2010.01203.x

Abstract The concept of Volunteered Geographic Information (VGI) has recently emerged from the new Web 2.0 technologies. The OpenStreetMap project is currently the most significant example of a system based on VGI. It aims at producing free vector geographic databases using contributions from Internet users. Spatial data quality becomes a key consideration in this context of freely downloadable geographic databases. This article studies the quality of French OpenStreetMap data. It extends the work of Haklay to France, provides a larger set of spatial data quality element assessments (i.e. geometric, attribute, semantic and temporal accuracy, logical consistency, completeness, lineage, and usage), and uses different methods of quality control. The outcome of the study raises questions such as the heterogeneity of processes, scales of production, and the compliance to standardized and accepted specifications. In order to improve data quality, a balance has to be struck between the contributors' freedom and their respect of specifications. The development of appropriate solutions to provide this balance is an important research issue in the domain of user‐generated content.

Quasistatic Contact Problems in Viscoelasticity and Viscoplasticity
Weimin Han, Mircea Sofonea
2002· AMS/IP studies in advanced mathematics664doi:10.1090/amsip/030

Nonlinear variational problems and numerical approximation: Preliminaries of functional analysis Function spaces and their properties Introduction to finite difference and finite element approximations Variational inequalities Mathematical modelling in contact mechanics: Preliminaries of contact mechanics of continua Constitutive relations in solid mechanics Background on variational and numerical analysis in contact mechanics Contact problems in elasticity Contact problems in viscoelasticity: A frictionless contact problem Bilateral contact with slip dependent friction Frictional contact with normal compliance Frictional contact with normal damped response Other viscoelastic contact problems Contact problems in visocplasticity: A Signorini contact problem Frictionless contact with dissipative potential Frictionless contact between two viscoplastic bodies Bilateral contact with Tresca's friction law Other viscoelastic contact problems Bibliography Index.

Marine reserves: size and age do matter
Joachim Claudet, Craig W. Osenberg, Lisandro Benedetti‐Cecchi, Paolo Domenici +4 more
2008· Ecology Letters657doi:10.1111/j.1461-0248.2008.01166.x

Marine reserves are widely used throughout the world to prevent overfishing and conserve biodiversity, but uncertainties remain about their optimal design. The effects of marine reserves are heterogeneous. Despite theoretical findings, empirical studies have previously found no effect of size on the effectiveness of marine reserves in protecting commercial fish stocks. Using 58 datasets from 19 European marine reserves, we show that reserve size and age do matter: Increasing the size of the no-take zone increases the density of commercial fishes within the reserve compared with outside; whereas the size of the buffer zone has the opposite effect. Moreover, positive effects of marine reserve on commercial fish species and species richness are linked to the time elapsed since the establishment of the protection scheme. The reserve size-dependency of the response to protection has strong implications for the spatial management of coastal areas because marine reserves are used for spatial zoning.

The Diversity of Parasites
Robert Poulin, Sergé Morand
2000· The Quarterly Review of Biology630doi:10.1086/393500

Parasitism is one of the most successful modes of life displayed by living organisms, as measured by how often it evolved and how many parasitic species are presently in existence. Studying the diversity of parasites is particularly relevant because sympatric diversification may be important in some parasite taxa, and because of the opportunity for independent tests of evolutionary hypotheses in the many separate lineages in which parasitism evolved. Our incomplete knowledge of existing parasite species--the result of a range of phenomena that includes inadequate sampling effort or the lumping of different cryptic species under one name--is not always a major obstacle for the study of parasite diversity. Patterns in the diversity of parasites may be associated with either host or parasite characteristics. The distribution of parasite diversity among host taxa does not simply reflect the species diversity of the host taxa themselves; life history and ecological traits of hosts appear to play important roles. These may determine the likelihood that hosts are colonized by parasite species over evolutionary time. It is not yet clear whether some host traits also favor intrahost speciation and diversification of parasites, and the formation of new parasite species. Certain features of parasites may also be associated with speciation and diversification. Only parasite body size has received much attention; the patterns observed are not greatly different from those of free-living species, with small-bodied parasite taxa being more speciose than related large-bodied taxa. Epidemiological parameters such as the basic reproductive rate of parasites, or R0, can also generate predictions regarding the distribution or evolution of parasite diversity. For instance, parasite taxa characterized by high R0 values may be more speciose than related taxa with lower values of R0; such predictions remain untested. Large-scale biogeographical patterns of diversity have only been well studied for metazoan parasites of marine fish; for these parasites, latitudinal patterns can be explained by effects of temperature on speciation rates and epidemiological variables, though other causes are possible. The emphasis for future research must shift from pattern description to the elucidation of the processes responsible for the structure and diversity of parasite faunas. A better integration of ecological and historical (or phylogenetic) approaches to the study of parasite diversity should make this objective possible.

Genomes of 13 domesticated and wild rice relatives highlight genetic conservation, turnover and innovation across the genus Oryza
Joshua C. Stein, Yeisoo Yu, Dario Copetti, Derrick J. Zwickl +4 more
2018· Nature Genetics627doi:10.1038/s41588-018-0040-0

The genus Oryza is a model system for the study of molecular evolution over time scales ranging from a few thousand to 15 million years. Using 13 reference genomes spanning the Oryza species tree, we show that despite few large-scale chromosomal rearrangements rapid species diversification is mirrored by lineage-specific emergence and turnover of many novel elements, including transposons, and potential new coding and noncoding genes. Our study resolves controversial areas of the Oryza phylogeny, showing a complex history of introgression among different chromosomes in the young ‘AA’ subclade containing the two domesticated species. This study highlights the prevalence of functionally coupled disease resistance genes and identifies many new haplotypes of potential use for future crop protection. Finally, this study marks a milestone in modern rice research with the release of a complete long-read assembly of IR 8 ‘Miracle Rice’, which relieved famine and drove the Green Revolution in Asia 50 years ago. Genome assemblies of 13 domesticated and wild rice relatives reveal salient features of genome evolution across the genus Oryza, especially rapid species diversification and turnover of transposons. This study also releases a complete long-read assembly of IR 8 ‘Miracle Rice’.

Worldwide distribution of continental rock lithology: Implications for the atmospheric/soil CO<sub>2</sub> uptake by continental weathering and alkalinity river transport to the oceans
Philippe Amiotte‐Suchet, Jean‐Luc Probst, Wolfgang Ludwig
2003· Global Biogeochemical Cycles598doi:10.1029/2002gb001891

The silicate rock weathering followed by the formation of carbonate rocks in the ocean, transfers CO 2 from the atmosphere to the lithosphere. This CO 2 uptake plays a major role in the regulation of atmospheric CO 2 concentrations at the geologic timescale and is mainly controlled by the chemical properties of rocks. This leads us to develop the first world lithological map with a grid resolution of 1° × 1°. This paper analyzes the spatial distribution of the six main rock types by latitude, continents, and ocean drainage basins and for 49 large river basins. Coupling our digital map with the GEM‐CO2 model, we have also calculated the amount of atmospheric/soil CO 2 consumed by rock weathering and alkalinity river transport to the ocean. Among all silicate rocks, shales and basalts appear to have a significant influence on the amount of CO 2 uptake by chemical weathering.

Global relationships of total alkalinity with salinity and temperature in surface waters of the world's oceans
Kitack Lee, Lan T. Tong, Frank J. Millero, Christopher L. Sabine +4 more
2006· Geophysical Research Letters595doi:10.1029/2006gl027207

A simple function of sea surface salinity (SSS) and temperature (SST) in the form A T = a + b (SSS − 35) + c (SSS − 35) 2 + d (SST − 20) + e (SST − 20) 2 fits surface total alkalinity (A T ) data for each of five oceanographic regimes within an area‐weighted uncertainty of ±8.1 μ mol kg −1 (1 σ ). Globally coherent surface A T data (n = 5,692) used to derive regional correlations of A T with SSS and SST were collected during the global carbon survey in the 1990s. Such region‐specific A T algorithms presented herein enable the estimation of the global distribution of surface A T when observations of SSS and SST are available.