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Dietary studies of marine predators offer an immediate signal of foodweb changes occurring at lower trophic levels, and therefore are often used to assess the ecosystem status of marine systems. Conventionally, these studies are based on morphological analysis of prey remains in stomach contents, involving invasive and destructive techniques to collect samples. More recently, the number of dietary studies based on less invasive biochemical and molecular approaches has dramatically increased. However, all three methods, morphological, biochemical and molecular, have well-documented limitations for resolving taxonomy, temporal variation or biomass composition. In this study, we minimise these limitations by considering multiple techniques in combination. As a case study, we report the target prey species and diet composition of a marine predator that has been used to assess annual change in managed fishing areas for several decades, the macaroni penguin Eudyptes chrysolophus . We use biochemical (stable isotope) and molecular (DNA) analysis of faecal samples collected across the different phases of a single breeding season, and compare the resolved diet to a 26-year dataset of stomach contents collected from a closely located colony (0.25 km apart) that exploits identical foraging grounds. Molecular analysis increased the known target prey species for this highly monitored population by 31%, including a fish species of commercial importance. Biochemical analysis detected subtle changes in the proportion of fish and krill in the diet, demonstrating promising opportunities for using a combined molecular and biochemical method to assess inter-annual foodweb changes at lower trophic levels. The combined approach offers a less invasive sampling methodology, compared to morphological analysis, and provides more information regarding prey species diversity and the overall trophic signature of the diet. Further studies are required to examine the feasibility of using this approach for long-term dietary studies of different marine predator species. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of the GnRH vaccine on the performance and meat quality of Holstein bulls fed high concentrate diets. A total of 493 approximately 7 month old bulls (initial BW 298 ± 1.2 kg) were allocated into 3 treatment groups, intact bulls ( n = 164), animals surgically castrated at 15 to 17 d of the study ( n = 164), and animals vaccinated on 0 and 28 d of the study with the GnRH vaccine ( n = 165). Animals were slaughtered between 131 and 133 d and carcass quality was evaluated. Hot carcass weight, dressing percentage, fat classification and meat quality parameters did not differ significantly between surgically castrated and vaccinated animals but differed ( P < 0.05) from intact bulls. Carcass classification, pH at 26 h, and fat color were not affected by treatment. [ABSTRACT FROM AUTHOR]

Abstract: In AD 365 a great (M w >8) earthquake lifted up western Crete, exposing a shoreline encrusted by marine organisms, and up to 10m of marine substrate beneath it. Radiocarbon ages determined for corals and bryozoans exposed between the paleo-shoreline and present sea level are consistent, within measurement error, with each other and with the date of the earthquake. But radiocarbon ages determined for the boring bivalve Lithophaga lithophaga found on the same substrate are at least 350years, and up to 2000years, older than the date of the earthquake that lifted them above sea level. These observations reveal two important effects that limit the use of radiocarbon lithophagid ages in tectonic and paleoseismological studies. The first is that the exceptional preservation potential of lithophagids allows them to remain intact and in situ long after natural death, while the substrate continues to be colonised until eventual uplift. The second, which we confirm with radiocarbon analysis of museum specimens of known age, is the incorporation of old (14C-free) carbon into lithophagid shells from the limestone host rock into which the lithophagids bored. The two effects are both significant in Crete and central Greece, and can cause the radiocarbon lithophagid ages to be up to 2000years older than the uplift event which exposed them. Understanding these effects is important because lithophagids are far more abundantly preserved, and used to date uplift, than most other marine organisms. This study shows that they can rarely be used to distinguish uplift events, or date them to better than 1000years, or even to distinguish whether observed uplift occurred in a single or in multiple events. After taking account of these uncertainties, the ages of the lithophagids are, however, consistent with the hypothesis that the highest prominent marine notches and exposed lithophagid holes within a few metres of sea level in Greece formed when sea level became relatively stable ~6000years ago, following rapid rise after the last glacial maximum. [Copyright &y& Elsevier]

Humpback whales (Megaptera novaeangliae) are showing strong recovery from commercial whaling in the western South Atlantic. In this region, humpback whales migrate annually from their winter breeding grounds off the coast of Brazil to their summer feeding grounds near to the Polar Front, an area that includes the waters of South Georgia and the South Sandwich Islands (SGSSI). This latter region includes a Marine Protected Area (MPA), which has been developed to ensure sustainable management of fisheries, and protection of foraging predators. To date, management measures within the MPA have primarily been concerned with foraging predators that rely upon Antarctic krill, including for a number of previously over-exploited species. With humpback whales increasing in the western South Atlantic, understandingnderstanding their spatiotemporal distribution within the MPA is important as it will help inform management particularly in respect of interactions between humpback whales and the regional fishery for Antarctic krill. Here we develop habitat models from the distribution and movement patterns of 16 individuals at their high-latitude feeding grounds, south of 50°S. We show that whale habitat use varies throughout the foraging period. Upon reaching their feeding ground, whales use the area to the east of the South Sandwich Islands, moving westward into the centre of the Scotia Arc and towards South Georgia during the high summer, and then expanding back towards the east in the winter. Based on these findings, we discuss the implications for the future, including necessary research required for underpinning management. [ABSTRACT FROM AUTHOR]

Abstract: Macroparasites of vertebrates usually occur in multi-species communities, producing infections whose outcome in individual hosts or host populations may depend on the dynamics of interactions amongst the different component species. Within a single co-infection, competition can occur between conspecific and heterospecific parasite individuals, either directly or via the host’s physiological and immune responses. We studied a natural single-host, multi-parasite model infection system (polystomes in the anuran Xenopus laevis victorianus) in which the parasite species show total interspecific competitive exclusion as adults in host individuals. Multi-species infection experiments indicated that competitive outcomes were dependent on infection species composition and strongly influenced by the intraspecific genetic identity of the interacting organisms. Our results also demonstrate the special importance of temporal heterogeneity (the sequence of infection by different species) in competition and co-existence between parasite species and predict that developmental plasticity in inferior competitors, and the induction of species-specific host resistance, will partition the within-host-individual habitat over time. We emphasise that such local (within-host) context-dependent processes are likely to be a fundamental determinant of population dynamics in multi-species parasite assemblages. [Copyright &y& Elsevier]

This study investigated associations between pre-treatment cytokine expression and infection patterns, before and after de-worming, in humans exposed to two gastrointestinal nematode species. Quantitative measures of Ascaris lumbricoides and Trichuris trichiura infection (based on faecal egg counts) were estimated immediately before and 8–9 months after treatment in a Cameroonian population. Whole blood cytokine responses to parasite-derived antigens were assayed immediately pre-treatment. An overall measure of the tendency towards species-specific infection (increasing with A. lumbricoides faecal egg counts and decreasing with T. trichiura faecal egg counts) was significantly positively related to IL-10 levels in older (14–57 year) hosts. There was a significant negative influence of IL-5 on reinfection probability in T. trichiura but not A. lumbricoides. This effect coincided with reduced reinfection success in T. trichiura compared to A. lumbricoides. TH2 cytokine expression by younger hosts (4–13 year) was negatively associated with contemporary A. lumbricoides faecal egg counts before treatment. Following treatment, the pre-treatment TH2 cytokine expression data for younger hosts (now reflecting responsiveness 8–9 months in the past) were negatively associated with T. trichiura faecal egg counts. Taken together, these observations suggest a successional interaction between TH2-driven immune responses and species infection over time. However, any differential effects of the measured immune responses on species-specific recruitment, maturation and mortality were superimposed upon (and outweighed by) the effects of other factors favouring coinfection. [Copyright &y& Elsevier]

Variation in host-specific infectivity was studied in monogenean polystome parasites (Protopolystoma spp.) of the interfertile, parapatric anurans Xenopus laevis laevis and Xenopus muelleri. Laboratory-raised host F1 hybrids were resistant to parasites respectively specific to each parent taxon in nature. This resistance occurred against parasite isolates from both inside and outside a host hybrid/sympatric zone (and no isolate was compatible with the foreign host species under experimental conditions). Geographical Protopolystoma xenopodis isolates showed variable infectivity to a single full-sib group of their usual host, X. l. laevis, and strains with high or low infectivity to these sibs co-occurred in spatially distant local areas (separated by 1,700 km). The host compatibility of P. xenopodis was also subject to host genotype×parasite genotype interactions. Refractoriness to some parasites or pathogens, as a consequence of hybridisation, may have conferred a selective advantage on the allopolyploid pathway by which most Xenopus spp. are believed to have evolved. [Copyright &y& Elsevier]

Comprehensive field data on polystomatid monogeneans record low prevalence and intensity of infection and suggest that worm burdens in this group are strongly regulated: thus, in the majority of Polystoma species infecting anuran amphibians mean abundance is typically less than one parasite/host. There is circumstantial evidence that the dominant control is attributable to host factors which over-ride variations in transmission success. This review provides a brief summary of information on Pseudodiplorchis americanus, a parasite of the desert toad, Scaphiopus couchii, and then focuses in detail on the spectrum of factors regulating infrapopulations of Protopolystoma xenopodis, a parasite of the aquatic Xenopus laevis. Infection levels of adult worms and their contribution to transmission are regulated by external environmental factors (especially temperature), by host factors (including behaviour and population density), and by a range of parasite factors including intra- and inter-specific competitive interactions and variations in intrinsic characters, especially survivorship and reproductive output. In addition to these factors whose primary effect is to modulate transmission rates, there is a major attrition in parasite numbers between invasion and maturity (3 months post-infection). Long-term laboratory experiments on the Xenopus laevis/Protopolystoma xenopodis interaction demonstrate a powerful acquired immune response. Primary infection is characterised by a high prevalence of established adult worms but the success of subsequent challenge infection is greatly reduced, leading to low prevalence and extended pre-patent period. In the small proportion of hosts supporting a second infection of adult parasites, surviving burdens are small (one to two worms/host) and show reduced egg production. These results provide an explanation for the low burdens encountered in field studies: a majority of adult X. laevis in natural populations are likely to exhibit strong, relatively long-term, post-infection immunity after the loss of a previous infection. [Copyright &y& Elsevier]

Studies the rerating capacity of a constructed wetland (CW) treatment system in Orlando, Florida. Actual total nitrogen and total phosphorus concentrations in the treatment system; Design influent concentrations; Summary of nutrient uptake during the capacity testing.

Examines the interaction between mantle upwelling, drainage evolution and active normal faulting. Relationship between gravity and topography; Localization of normal faulting; Competition between regional capture and local.

Investigates the ruptures of earthquakes in Kerman, Iran. Use of observations of surface faulting, analysis of body waves, interferometry and geomorphology; Probability of ruptures to occur at the fault system; Achievement of regional kinematics.

Evaluates the sequence of earthquakes in Iran on 1994. Occurrence of motion on blind thrusts; Involvement of bedding-plane slip on the coseismic ruptures of the surface; Recognition of active tectonics.

Evaluates the tectonic and hazard contexts of the 1999 earthquakes in Turkey. Seismic activity of the Marmara Sea; Relation of the long-term distribution of large earthquakes to Quaternary faults; Contribution of seismic slip on faults to the tectonic motion in the region.

Argues that the upper mantle beneath the continents has relatively little strength and the effective strength of the continental lithosphere is in the seismogenic crust. Focal depth distribution of earthquakes; Effective elastic thickness on the continents; Strength of the continental lithosphere and the height of mountain belts.

Assesses the faulting of the Mogod earthquake in Mongolia. Synthesis of the information on surface ruptures and satellites imagery; Association of the main shohl rupture to the coseismic surface faulting; Insights of the surface faulting and seismology with geomorphology in ways of faulting evolves.

Investigates the 1997 May 10 Zirkuh-e-Qa'enat earthquake faulting along the Sistan zone of Iran. Analysis of the body-wave seismograms from the main shock; Change in fault style; Average coseismic surface displacements.

Examines the surface faulting in historical and recent earthquakes in the Eastern Mediterranean region and Middle East. Number of cases of active and inactive faulting; Importance of information on the studies of active tectonics and palaeoseismology; Derivation of relationship between magnitude and rupture length.

• Synthesis and extraction mechanisms of sulfur donating extractants. • Speciation of actinide and lanthanide complexes in solvent extraction. • Collection of Am/Eu separation factors for assorted dithiophosphinic acids. The effective separation of trivalent actinides and lanthanides is capable of reducing the long term radiation hazard associated with used nuclear fuel. This class of separation exploits the tendency of ligands containing large and polarizable soft donor atoms to preferentially bind to the trivalent actinides instead of the lanthanides. Among the soft donors, nitrogen and sulfur based ligands have received the most attention with sulfur donors generally having greater selectivity for the actinides. Herein, the speciation, mechanism, and selectivity for the extraction of lanthanides and actinides from aqueous media into an organic phase by various sulfur containing extractants is reviewed. [ABSTRACT FROM AUTHOR]

Abstract: Bos indicus bulls 20months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at d0 and d91 (group IC, n=144) or were surgically castrated on d91 (group SC, n=144). Slaughter on d280, was 27weeks after castration. Adverse safety issues in 8% of group SC bulls following surgery contrasted with 0% in group IC bulls. At d105 testosterone levels were suppressed to similar levels in both groups. Importantly, group IC bulls had higher live weight, hot carcass weight, ADG (P <0.005) and dressing percentage (P <0.0001) compared to group SC animals. There were no negative effects on carcass or meat quality traits, thus immunocastration was concluded to offer a safe and effective method that provides production gains, and improves animal welfare in Bos indicus beef bulls without impacting meat and carcass quality. [Copyright &y& Elsevier]

Abstract: We investigate the depth and geometry of faulting within a cluster of buried, reverse faulting earthquakes that struck Qeshm island, in the Zagros fold-and-thrust belt, over a four year period between November 2005 and July 2009. Of particular interest is our observation that there was a vertical separation between the largest two earthquakes (M w 5.8 and 5.9), which ruptured the lower parts of a ∼10-km thick sedimentary cover, and microseismicity recorded by a local network after the first, M w 5.8 event, which was concentrated within the underlying basement at depths of 10–20km. Although measured in different ways — the largest three earthquakes using radar interferometry, moderate-sized events with teleseismically-recorded, long-period waveforms, and the microseismicity using data from a local seismic network — we used consistent velocity and elastic parameters in all our modelling, and the observed vertical separation is robust and resolvable. We suggest that it reflects the influence of the Proterozoic Hormuz salt, a weak layer at the base of the sedimentary cover across which rupture failed to propagate. Because the full thickness of the seismogenic layer failed to rupture during the largest earthquakes in the sequence, the lower, unruptured part may constitute a continued seismic hazard to the region. Considering the rarity of earthquakes larger than M w 6.2 in the Zagros Simply Folded Belt, we suggest that the Hormuz salt forms an important, regional barrier to rupture, not just a local one. Finally, we note that buried faulting involved in the largest earthquakes is almost perpendicular to the trend of an anticline exposed at the surface immediately above them. This suggests that locally, faulting and folding are decoupled, probably along a weak layer of marls or evaporites in the middle part of the sedimentary cover. [Copyright &y& Elsevier]