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Presents information on a study which aimed to determine the factors which control the abundance of herbivores in an ecosystem while evaluating the relationship between net primary production (NPP), autotrophic nitrogen content and herbivory. Information on ecosystems dominated by richer autotrophs; How NPP and herbivory rates were expressed; Relation of NPP to autotrophic nitrogen content.

Discusses a survey of the development of gene therapy in Europe and the U.S. Barriers to the process of converting today's science into tomorrow's technology; Countries that are best placed to reap the rewards of gene therapy research; Comparative analysis of the innovation process in Great Britain and the U.S.

Deforestation for agriculture in the tropics, followed by abandonment, has resulted in large areas of secondary forest. Some authors have suggested that this secondary regrowth could help prevent mass extinction in the tropics by providing habitat for forest species. However, there is little generalised understanding of the biodiversity value of secondary forest. To address this knowledge gap, we conducted an analysis of avian responses to secondary forest succession, comparing data from 44 tropical secondary forest sites with nearby primary forest sites and investigating both species and functional diversity based metrics. Total species richness in secondary forests was 12% lower than in primary forests and was not related to secondary forest age. In contrast, forest specialist species richness increased with time since disturbance, reaching 99% of primary forest values after 100 years. In terms of functional diversity, functional dispersion (FDis) and functional divergence (FDiv) were similar in primary and secondary forests. However, functional evenness (FEve) was 5% higher in secondary than in primary forests. The standardized effect size of functional diversity (sesFD) was higher in young secondary forests than primary forests and declined with time since disturbance. Overall, these results suggest that secondary tropical forests can support provision of ecosystem services but that these services may be less stable in young forests. Therefore, secondary tropical forests, particularly older regrowth, have biodiversity value and can support important ecosystem functions. These secondary forests should be protected from further disturbance but preserving primary forest is vital for supporting overall and forest specialist species richness. [ABSTRACT FROM AUTHOR]

Abstract: 3D seismic data are used to establish the origin and timing of layer-bound arrays of radial faults within a 1500-m-thick sequence of polygonally faulted, Eocene to middle Miocene claystones penetrated by two adjacent salt stocks in the UK Central Graben. Polygonal faults are organised into six laterally extensive tiers that formed during sediment compaction and dewatering during early burial. Dip and amplitude attributes of faulted horizons within the centre of the tiers shows that regional polygonal fault patterns change to radial patterns around the two salt stocks which have radii of c. 1.5 and 2.5 km respectively. Radial faults are confined to the same (120–450 m thick) tiers as those of polygonal faults, indicating that they are also layer bound. The radial-fault pattern in each tier is distinctive and commonly shows a range of fault spacings (154–356 m), maximum throws (7–40 ms), and C-shaped displacement–distribution profiles similar to those of laterally equivalent polygonal faults. These layer-bound radial faults are interpreted as a form of polygonal faults in which strikes have been strongly aligned by a local stress perturbation of salt stocks. Timing constraints indicate that layer-bound arrays of polygonal and radial faults formed in discrete phases during and at the close of sedimentation of each tier. The six tiers formed during the early Eocene, late Eocene, early Oligocene, late Oligocene, early Miocene and middle Miocene. The distance of the polygonal–radial-fault transition from the salt stocks vary from tier to tier but are typically within 800–4000 m of the salt-sediment contact. The position of the transition boundary is used to reconstruct the lateral limit of the salt/sediment-boundary-parallel stress or hoop stress field during key stages in the evolution of the Pierce salt stocks. The position of the radial–polygonal fault transition could be caused by two possible mechanisms: (1) limit of circumferential stretching caused by arching during diapiric rise or (2) lateral limit of hoop stresses produced by radial loading of the overburden from a pressurised salt stock. [Copyright &y& Elsevier]

Abstract: Ceratocystis fimbriata sensu lato represents a complex of cryptic and commonly plant pathogenic species that are morphologically similar. Species in this complex have been described using morphological characteristics, intersterility tests and phylogenetics. Microsatellite markers have been useful to study the population structure and origin of some species in the complex. In this study we sequenced the genome of C. fimbriata. This provided an opportunity to mine the genome for microsatellites, to develop new microsatellite markers, and map previously developed markers onto the genome. Over 6000 microsatellites were identified in the genome and their abundance and distribution was determined. Ceratocystis fimbriata has a medium level of microsatellite density and slightly smaller genome when compared with other fungi for which similar microsatellite analyses have been performed. This is the first report of a microsatellite analysis conducted on a genome sequence of a fungal species in the order Microascales. Forty-seven microsatellite markers have been published for population genetic studies, of which 35 could be mapped onto the C. fimbriata genome sequence. We developed an additional ten microsatellite markers within putative genes to differentiate between species in the C. fimbriata s.l. complex. These markers were used to distinguish between 12 species in the complex. [Copyright &y& Elsevier]

Abstract: In this paper we study the effects of negative Poisson''s ratios on elastic problems containing singularities. Materials with a negative Poisson''s ratio are termed auxetic. We present a brief review of such materials. The elasticity problem of a bimateral wedge is presented, then two particular cases of this problem are investigated: the free-edge problem and the interface crack problem. We study the effect on the stress singularity due to one portion of the bimaterial becoming auxetic. We find that the auxetic material has a significant effect on the singularity order, even causing the singularity to vanish for certain values of the elastic constants. [Copyright &y& Elsevier]

The purpose of this study was to determine the effects of contrasting agricultural practices in organic and conventional farming (local factors), and to evaluate the influence of surrounding landscape features (regional factors) on plant assemblages, taking into account habitat structure. Plants were inventoried in crop fields and woody hedgerows (boundary and centre) of 16 conventional and 14 organic sites. Habitat structure, agricultural practices and landscape characteristics were quantified for each habitat. Hedgerow boundaries contained a higher number of plant species than adjacent habitats although many of them were exotics. However, exotics comprised a decreasing proportion of species richness from field to hedgerow centre. Many of the exotic species were shared between crop fields and adjacent boundaries. There was a clear difference in species richness and composition between the organic and conventional study sites. Fields and woody hedgerows situated in organic sites consistently harboured more native and exotic plant species than those in conventional systems. Numerous species were only found in organic hedgerows and included several long-lived herbaceous forest species. At the larger scale level, old-fields (areas with sparse shrubs and trees re-colonizing cleared land) were the only habitats that significantly influenced the species composition of hedgerows, particularly exotic species. Conversely, farm type was a significant predictor of native species richness. [Copyright &y& Elsevier]

Objective: Endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) is an essential tool in the diagnosis of pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy of cytology from EUS‐FNA, to correlate the results with the corresponding histopathological diagnoses and to analyse the impact of retrospective assignment of the Papanicolaou Society of Cytopathology (PSC) reporting system categories. Methods: All pancreatic FNA specimens reported at the Royal Free Hospital during a 2‐year period were retrospectively collected and assigned to the PSC system categories. Any available corresponding histological samples were assessed for concordance. Results: In total, 236 cytology specimens from 223 patients were identified, of which 108 (45.8%) had corresponding histology samples. The main reason for cyto‐histological discrepancy was sampling error. Interpretive error was identified in one case. Overall, sensitivity was 92.5%, specificity was 100%, diagnostic accuracy of cytology was 95%, false‐positive rate was 0% and false‐negative rate was 7.5%. The implementation of the new reporting system reduced the number of cases in the atypical category. All cases previously categorised as suspicious or malignant remained in the same category. Conclusions: EUS‐FNA is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system enhances standardisation of the reporting terminology and reduces the number of samples in the non‐standardised and equivocal atypical category. Endoscopic ultrasound‐guided fine needle aspiration is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system reduces the number of samples in the atypical category. [ABSTRACT FROM AUTHOR]

Lateral shortening is expressed in unique ways in salt basins, especially if pre-shortening diapirs are present. We present an overview of previously-published and new physical models and present new 3-D conceptual models that capture the evolution of shortening structures in salt provinces dominated by precursor isolated diapirs (termed isolated-diapir provinces ). In such provinces, isolated diapirs form only a minor volumetric component of a sedimentary basin, however, due to the relative weakness of rock salt and their ability to localize strain, during shortening they have a disproportionately large influence on structural development. We find three key mechanical principles govern the processes and structural styles developed during shortening of isolated-diapir provinces. First, salt diapirs shorten before surrounding sedimentary rocks due to their relative weakness, and so form salients in the thrust front during early shortening. Second, diapirs tend to nucleate folds and faults, which radiate out from the diapirs. Third, as diapir walls converge, the roof must shorten. Extrusive salt sheets are expelled through thin roofs, but thicker roofs resist piercement and so tend to undergo complex folding and faulting. As a result of these principles, the first-order controls on the structural styles expressed across a shortened isolated-diapir province are the configuration the diapir array prior to shortening, the connectivity of these diapirs prior to shortening, total strain magnitude, and diapir roof thickness. Second-order controls include the initial cross-sectional and map-view geometry of diapirs, diapir size, and diapir orientation with respect to the shortening direction. [ABSTRACT FROM AUTHOR]

Urban effluent potential toxicity was assessed by a battery of biomarkers aimed at determining sub-lethal effects after continuous exposure on the marine organism Solea senegalensis . Specimens were exposed to five effluent concentrations (1/2, 1/4, 1/8, 1/16, 1/32) during 7-days, simulating the dispersion plume at the discharge point. Three different groups of biomarkers were selected in the present study: biomarkers of exposure (Phase I: EROD and DBF; Phase II: GST), biomarkers with antioxidant responses (GR and GPX) and biomarkers of effects (DNA damage and LPO). Additionally, a biological depuration treatment (photobiotreatment (PhtBio)) was tested in order to reduce the adverse effects on aquatic organisms. Effluent exposure caused sub-lethal responses in juvenile fish suggesting oxidative stress. After PhtBio application, concentrations of the major part of measured contaminants were reduced, as well as their bioavailability and adverse effects. [ABSTRACT FROM AUTHOR]

Intrasalt sediment packages containing siliciclastic sediments, carbonate sediments, or non-halite evaporites such as gypsum or anhydrite are common within most salt sequences. Intrasalt sediment packages may have been deposited before, during, or after salt deposition and be incorporated into the salt by various processes. Understanding the origin and evolution of intrasalt sediment packages may yield important insights into the tectonic and geodynamic history of the basin, and also into the understanding of salt tectonics. Despite the importance of intrasalt sediment packages, currently there is no systematic description of their possible origins and their distinguishing criteria. This work is divided into three parts. The first part outlines the possible origins of intrasalt sediment packages, as well as criteria to determine if they originated as subsalt, suprasalt or intrasalt sequences. The second part examines how sediment packages that originated on top of salt, such as minibasins, can be encased within salt. Four key encasement processes are proposed: a) salt expulsion from beneath a minibasin experiencing density-driven subsidence; b) salt expulsion from beneath adjacent subsiding minibasins; c) salt expulsion associated with lateral shortening; d) override of minibasins by a salt sheet sourced from elsewhere. The third part of the paper presents a case study from the SE Precaspian Basin, Kazakhstan, where, using a borehole-constrained 3D seismic reflection dataset, the proposed criteria are applied to an area with abundant, newly discovered sediment packages within salt. [ABSTRACT FROM AUTHOR]

Minibasin provinces are widespread and can be found in all types of salt tectonic settings, many of which are prone to shortening. Previous studies of how minibasin provinces shorten assume that the salt between the minibasins is homogeneous and that the base of salt is flat or of low relief, such that minibasins are free to move laterally. Here we investigate how minibasin provinces respond to shortening when the lateral mobility of the minibasins is restricted by intra-salt sediment bodies, in order to gain a greater understanding of the controls on the structural styles and modes of tectono-stratigraphic evolution exhibited in minibasin provinces. We examine a borehole-constrained, 3D seismic reflection dataset from the SE Precaspian Basin (onshore western Kazakhstan). The study area is characterised by large, supra-salt minibasins and an array of smaller intra-salt sediment packages distributed between these larger minibasins. We first outline the evidence of episodic shortening between the Late Triassic and present, after the onset of supra-salt minibasin subsidence. Next, we document spatial variations in shortening style, showing how these relate to the concentration of intra-salt sediment packages. Finally, we develop synoptic models showing how intra-salt sediment packages influence both the lateral mobility of minibasins during shortening and the resultant structural style, and we compare and contrast our findings with existing models and other natural examples of shortened minibasin provinces. We conclude that minibasin provinces may have different degrees of lateral mobility depending on the presence, or absence, of intrasalt barriers, and that these variations provide a first-order control on basin-shortening style and tectono-stratigraphic evolution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bradyrhizobium species isolated from diverse legumes in South Africa. • Delineation of these species following the genealogical concordance approach. • Novel Bradyrhizobium species represent nodA alleles specific to South African Clades. • Bradyrhizobium species may have agricultural importance in sub-Saharan Africa. Africa is known for its rich legume diversity with a significant number of endemic species originating in South Africa. Many of these legumes associate with rhizobial symbionts of the genus Bradyrhizobium , of which most represent new species. Yet, none of the Bradyrhizobium species from South Africa have been described. In this study, phylogenetic analysis of 16S rRNA gene sequences of fourteen strains isolated in southern Africa from root nodules of diverse legumes (i.e., from the tribes Crotalarieae, Acacieae, Genisteae, Phaseoleae and Cassieae) revealed that they belong to the Bradyrhizobium elkanii supergroup. The taxonomic position and possible novelty of these strains were further interrogated using genealogical concordance of five housekeeping genes (atpD, dnaK, glnII, gyrB and rpoB). These phylogenies consistently recovered four monophyletic groups and one singleton within Bradyrhizobium. Of these groups, two were conspecific with Bradyrhizobium brasilense UFLA 03-321T and Bradyrhizobium ivorense CI-1BT, while the remaining three represented novel taxa. Their existence was further supported with genome data, as well as metabolic and physiological traits. Analysis of nodA gene sequences further showed that the evolution of these bacteria likely involved adapting to local legume hosts and environmental conditions through the acquisition, via horizontal gene transfer, of optimal symbiotic loci. We accordingly propose the following names Bradyrhizobium acaciae sp. nov. 10BBT (SARCC 730T = LMG 31409T), Bradyrhizobium oropedii sp. nov. Pear76T (SARCC 731T = LMG 31408T), and Bradyrhizobium altum sp. nov. Pear77T (SARCC 754T = LMG 31407T) to accommodate three novel species, all of which are symbionts of legumes in South Africa. [ABSTRACT FROM AUTHOR]

A near-infrared diode laser-based spectrometer has been designed and built for the remote sensing of vehicle emissions. It detects carbon monoxide and carbon dioxide absorptions around 1580 nm and can provide the ratio CO/CO2 for vehicle exhaust studies. The system is battery powered and is designed to sit unobtrusively at the side of the road. The optics and electronics of the system is described and preliminary results are presented from field trials. Extensions to the spectrometer in terms of sensitivity by detection of the more intense first overtone of carbon monoxide around 2320 nm are described, in addition to further work on other species of interest. [Copyright &y& Elsevier]