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Recent Revision (recent + revision)

Distribution by Scientific Domains

Life Sciences	33%
Medical Sciences	25%

Selected Abstracts

Index Pteridophytorum Guadalupensium or a revised checklist to the ferns and club mosses of Guadeloupe (French West Indies)

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2009
MAARTEN J. M. CHRISTENHUSZ
Recent revision of the fern diversity of the French Caribbean island of Guadeloupe and its dependencies (Marie Galante, Les Saintes and La Désirade) resulted in the listing of 292 native ferns and club mosses in 28 families and 88 genera, of which eight ferns are endemic to Guadeloupe and 20 taxa are only recorded from the Lesser Antilles. Additionally, 21 species have recently been found to be naturalized. Nineteen new combinations are made and a new hybrid is described. Many types from the Fée collection have been reassessed and a number of names are lecto- or neotypified. Studied specimens are cited and localities are provided. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 213,277. [source]

Rethinking axial patterning in amphibians

DEVELOPMENTAL DYNAMICS, Issue 4 2002
Mary Constance Lane
Abstract Recent revisions in the Xenopus laevis fate map led to the designation of the rostral/caudal axis and reassignment of the dorsal/ventral axis (Lane and Smith [1999] Development 126:423,434; Lane and Sheets [2000] Dev. Biol. 225:37,58). It is unprecedented to reassign primary embryonic axes after many years of research in a model system. In this review, we use insights about vertebrate development from anatomy and comparative embryology, as well as knowledge about gastrulation in frogs, to reexamine several traditional amphibian fate maps. We show that four extant maps contain information on the missing rostral/caudal axis. These maps support the revised map as well as the designation of the rostral/caudal axis and reassignment of the dorsal/ventral axes. To illustrate why it is important for researchers to use the revised map and nomenclature when thinking about frog and fish embryos, we present an example of alternative interpretations of "dorsalized" zebrafish mutations. © 2002 Wiley-Liss, Inc. [source]

Defining targets in myeloproliferative disorders: reflecting on what is important,

HEMATOLOGICAL ONCOLOGY, Issue S1 2009
Martin Griesshammer
Abstract The current lack of curative options for essential thrombocythaemia (ET) leads to the goal of reducing the risk of potentially life-threatening thrombohaemorrhagic complications with long-term treatment. The setting of relevant treatment targets is an important consideration in this process, allowing the monitoring of disease control. Recent revisions to the World Health Organization (WHO) diagnostic criteria for the chronic MPDs 1 have implications not only for the diagnosis of patients, but also for the management of their disease and the continuing assessment of their progress. The purpose of this article is to discuss recent revisions to the WHO guidelines, and their influence on the setting of treatment targets in patients with ET. Copyright © 2009 John Wiley & Sons, Ltd. [source]

EU emissions trading: Legitimacy and stringency

ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 5 2010
Jon Birger Skjærseth
Abstract In December 2008, the EU Emissions Trading System (EU ETS) was significantly revised and strengthened. This article explores the basis for, and the consequences of, the revision for legitimacy. The key to legitimate EU governance is seen in the convergence of different sources of legitimacy at various levels of society. In addition to member-state consent, participation of non-state actors, democracy, expertise and effectiveness are of relevance. The first conclusion is that the recent revision of the EU ETS has indeed been grounded in a broader multilevel legitimacy basis. Second, the system faces significant challenges with regard to carbon markets and effectiveness, which could reduce its legitimacy in the long term. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment. [source]

EVOLUTION OF POECILOGONY AND THE BIOGEOGRAPHY OF NORTH AMERICAN POPULATIONS OF THE POLYCHAETE STREBLOSPIO

EVOLUTION, Issue 4 2000
Stefan R. Schulze
Abstract. Invertebrate interspecific developmental patterns can be highly variable and, taxonomically, are considered only weakly constrained. Intraspecifically, some invertebrate species possess multiple developmental modes,a condition known as poecilogony. Closer examination of most putative poecilogenous species, however, has not supported poecilogony, but rather has uncovered hidden or cryptic species. The polychaete Streblospio benedicti is a well-known, poecilogenous species found along the coast of North America. We collected mitochondrial cytochrome subunit I DNA sequence data from 88 individuals taken from 11 locations along the Atlantic, Gulf, and Pacific Coasts of the United States to provide a phylogenetic framework from which to interpret intraspecific variation in larval life history and brooding structure morphology in this species. Our results are consistent with a recent revision of the species into two separate species: S. benedicti, a pouched brooding form distributed along the Atlantic and Pacific Coasts, and S. gynobranchiata, a branchiate brooding form in the Gulf of Mexico. Contrary to the redescription, S. benedicti is paraphyletic because the pouched brooding population in Vero Beach, Florida shows strong genetic affinity with Gulf of Mexico populations (S. gynobranchiata). However, S. benedicti is a true poecilogenous species, with both lecithotrophic and planktotrophic individuals possessing identical mitochondrial DNA haplotypes. Crossbreeding experiments further support the molecular phylogeny with reproductive isolation demonstrated between, but not within, the major phylogenetic clades consistent with the previously described species. The genetic break near Vero Beach, Florida, corresponds to a well-known phylogeographic boundary, but the estimated time of separation for the Streblospio spp., approximately 10 million years before present, predates all other known phylogeographic subdivisions in this area. This suggests that biogeographic sundering in this region is a recurrent event. Divergence times within the major Streblospio spp. clades are recent and indicate that changes in larval life history as well as brooding structure morphology are highly plastic and can evolve rapidly. [source]

Enigmatic sedimentary,volcanic successions in the central European Variscides: a Cambrian/Early Ordovician age for the Wojcieszów Limestone (Kaczawa Mountains, SW Poland) indicated by SHRIMP dating of volcanic zircons

GEOLOGICAL JOURNAL, Issue 4 2008
Ryszard Kryza
Abstract Metamorphosed volcanic and sedimentary successions in the central European Variscides are, in many areas, poorly biostratigraphically constrained, making palaeotectonic interpretations uncertain. In such instances, geochronological data are crucial. Sensitive high resolution ion microprobe (SHRIMP) dating of volcanic zircons from a quartz,white mica schist (interpreted as deformed metavolcaniclastic/epiclastic rock) within the stratigraphically controversial Wojcieszów Limestone of the Kaczawa Mountains (Sudetes, SW Poland), near to the eastern termination of the European Variscides, has yielded an age of 498,±,5,Ma (2, error), corresponding to late Cambrian to early Ordovician magmatism in that area and constraining the depositional age of the limestones. The new SHRIMP data are not consistent with the recent revision of the age of the Wojcieszów Limestone based on Foraminifera findings that ascribed them to a Late Ordovician,Silurian or even younger interval. They are though, consistent with sparse macrofossil data and strongly support earlier interpretations of the lower part of the Kaczawa Mountains succession as a Cambrian,Early Ordovician extensional basin-fill with associated initial rift volcanic rocks, likely emplaced during the breakup of Gondwana. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Species in the genus Turritopsis (Cnidaria, Hydrozoa): a molecular evaluation

JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2007
M. P. Miglietta
Abstract Mitochondrial ribosomal gene sequences were used to investigate the status of several populations of hydromedusae belonging to the genus Turritopsis (family Oceaniidae). Several nominal species have been described for this genus, but most of them had been synonymized and attributed to one cosmopolitan species, Turritopsis nutricula. A recent revision based on morphological and reproductive characters, however, has shown that many different populations can be distinguished and that several of the nominal Turritopsis species are likely valid biological species. Our investigation using molecular sequence data of 16S mitochondrial gene confirms these results. The Mediterranean Turritopsis must be attributed to Turritopsis dohrnii and the Turritopsis of New Zealand must be referred to Turritopsis rubra. The situation of the Japanese Turritopsis is more complex, though all sampled populations are clearly distinct from T. nutricula, a species likely confined to the Western Atlantic. The Japanese Turritopsis fall into three widely separated lineages. One of them, corresponding likely to Turritopsis pacifica, is closely related to T. rubra. A second clade, which potentially represents an as yet undescribed species, produces smaller medusae than T. pacifica and is morphologically distinguishable from it. Finally, a third group was distinguished by a single haplotype sequence that is identical with a Mediterranean sample of T. dohrnii. It is postulated that the last group of Japanese Turritopsis is likely a recent introduction, most probably by human activity. A survey of all known and potentially valid Turritopsis species is given in table format to facilitate identifications and future revisory work. Sommario Sequenze del gene mitocondriale 16S sono state utilizzate per studiare lo stato tassonomico di idroidi appartenenti al genere Turritopsis (Famiglia Oceaniidae). In letteratura, tra le numerose specie nominali di TurritoSPSis descritte, molte di queste sono state successivamente messe in sinonimia e attribuite ad un'unica specie cosmopolita, Turritopsis nutricula. Una recente revisione, basata su dati morfologici e caratteri riproduttivi, ha comunque mostrato che diverse popolazioni di Turritopsis possono essere distinte in numerose specie nominali e probabilmente rappresentano valide specie biologiche. Il presente studio conferma questa recente interpretazione, mediante lo studio di sequenze molecolari del gene 16S. La popolazione mediterranea di Turritopsisè ora attribuita a T. dohrnii, mentre la popolazione neozelandese va ascritta alla specie T. rubra. La situazione nei mari giapponesi si presenta piu' complessa, sebbene tutte le popolazioni ivi campionate siano chiaramente distinte da T. nutricula, la quale risulta confinata unicamente all'Atlantico Orientale. Le sequenze ottenute da esemplari di Turritopsis provenienti dal Giappone formano tre cladi ben distinti. Uno di essi corrisponde a Turritopsis pacifica. Un secondo clade è costituito da popolazioni che producono meduse piu' piccole rispetto a Turritopsis pacifica ed e' dunque anche morfologicamente separato. Un terzo gruppo e' rappresentato da un solo aplotipo identico alle popolazioni mediterranee di T. dohrnii. La presenza di quest'ultimo gruppo di Turritopsis in Giappone e' molto probabilmente il risultato di un'introduzione recente, in seguito ad attività umana. Per facilitare futuri lavori di revisione, è inoltre presentata tavola che riassume le caratteristiche di tutte le specie di Turritopsis conosciute e potenzialmente valide. La tavola cerca di integrare i dati morfologici e riproduttivi già noti e dei dati molecolari ottenuti con questo studio. [source]

Forecasting Substantial Data Revisions in the Presence of Model Uncertainty,

THE ECONOMIC JOURNAL, Issue 530 2008
Anthony Garratt
A recent revision to the preliminary measurement of GDP(E) growth for 2003Q2 caused considerable press attention, provoked a public enquiry and prompted a number of reforms to UK statistical reporting procedures. In this article, we compute the probability of ,substantial revisions' that are greater (in absolute value) than the controversial 2003 revision. The predictive densities are derived from Bayesian model averaging over a wide set of forecasting models including linear, structural break and regime-switching models with and without heteroscedasticity. Ignoring the nonlinearities and model uncertainty yields misleading predictives and obscures recent improvements in the quality of preliminary UK macroeconomic measurements. [source]

Pushing the Dead into the Next Reproductive Frontier: Post Mortem Gamete Retrieval under the Uniform Anatomical Gift Act

THE JOURNAL OF LAW, MEDICINE & ETHICS, Issue 2 2009
Bethany SpielmanArticle first published online: 3 JUN 200
In re Matter of Daniel Thomas Christy authorized post mortem gamete retrieval under the most recent revision of the Uniform Anatomical Gift Act. This article recommends that the National Conference of Commissioners on Uniform State Laws explicitly address the issue of post mortem gamete retrieval for reproductive purposes; that legislators specify whether their states will follow the Christy ruling; and that ethics committees and consultants prepare for the questions about human identity and self determination that post mortem gamete retrieval raises. [source]

Toward the Complete Prediction of the 1H and 13C NMR Spectra of Complex Organic Molecules by DFT Methods: Application to Natural Substances

CHEMISTRY - A EUROPEAN JOURNAL, Issue 21 2006
Alessandro Bagno Prof.
Abstract The NMR parameters (1H and 13C chemical shifts and coupling constants) for a series of naturally occurring molecules have been calculated mostly with DFT methods, and their spectra compared with available experimental ones. The comparison includes strychnine as a test case, as well as some examples of recently isolated natural products (corianlactone, daphnipaxinin, boletunone B) featuring unusual and/or crowded structures and, in the case of boletunone B, being the subject of a recent revision. Whenever experimental spectra were obtained in polar solvents, the calculation of NMR parameters was also carried out with the Integral Equation-Formalism Polarizable Continuum Model (IEF-PCM) continuum method. The computed results generally show a good agreement with experiment, as judged not only by statistical parameters but also by visual comparison of line spectra. The origin of the remaining discrepancies is attributed to the incomplete modeling of conformational and specific solvent effects. [source]

Defining targets in myeloproliferative disorders: reflecting on what is important,

The shared epitope hypothesis in rheumatoid arthritis: Evaluation of alternative classification criteria in a large UK Caucasian cohort

ARTHRITIS & RHEUMATISM, Issue 5 2008
Ann W. Morgan
Objective Many classification systems for the HLA,DRB1 allelic association with rheumatoid arthritis (RA) have been reported, but few have been validated in additional populations. We sought to evaluate 3 different DRB1 allele classification systems in a large cohort of Caucasian RA patients and control subjects in the UK. Methods HLA,DRB1 typing was undertaken in 1,325 Caucasian RA patients and 462 healthy Caucasian controls who were residents of the UK. Logistic regression analyses were performed to investigate the different classification systems. Results We confirmed the association between the susceptibility alleles S2 and S3P, as proposed by Tezenas du Montcel, and the presence of RA in UK Caucasians. A significant hierarchy of risk was observed within the S3P allele group. There was no evidence of a significant association between DRB1*1001 and RA. Our data did not support the hypothesis that an isoleucine at position 67 conferred protection against RA, other than in contrast to the susceptibility alleles. However, the presence of an aspartic acid at amino acid 70 did appear to confer some degree of protection. Conclusion We were unable to fully substantiate any of the 3 recent revisions of the shared epitope hypothesis in this large cohort of Caucasian RA patients and control subjects in the UK. This reinforces the importance of evaluating disease susceptibility alleles in different Caucasian populations as well as in other ethnic groups. In particular, it will be important to clarify the precise DRB1 association in a given population before DRB1 genotyping is incorporated into clinical diagnostic or treatment algorithms. [source]