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Adrenomedullin (AM) and amylin are involved in angiogenesis/lymphangiogenesis and glucose homeostasis/food intake, respectively. They activate receptor activity-modifying protein (RAMP)/G protein-coupled receptor (GPCR) complexes. RAMP3 with the calcitonin receptor-like receptor (CLR) forms the AM(2) receptor, whereas when paired with the calcitonin receptor AMY(3) receptors are formed. RAMP3 interacts with other GPCRs although the consequences of these interactions are poorly understood. Therefore, variations in the RAMP3 sequence, such as single nucleotide polymorphisms or mutations could be relevant to human health. Variants of RAMP3 have been identified. In particular, analysis of AK222469 (Homo sapiens mRNA for receptor (calcitonin) activity-modifying protein 3 precursor variant) revealed several nucleotide differences, three of which encoded amino acid changes (Cys40Trp, Phe100Ser, Leu147Pro). Trp56Arg RAMP3 is a polymorphic variant of human RAMP3 at a conserved amino acid position. To determine their function we used wild-type (WT) human RAMP3 as a template for introducing amino acid mutations. Mutant or WT RAMP3 function was determined in Cos-7 cells with CLR or the calcitonin receptor (CT((a))). Cys40Trp/Phe100Ser/Leu147Pro RAMP3 was functionally compromised, with reduced AM and amylin potency at the respective AM(2) and AMY(3(a)) receptor complexes. Cys40Trp and Phe100Ser mutations contributed to this phenotype, unlike Leu147Pro. Reduced cell-surface expression of mutant receptor complexes probably explains the functional data. In contrast, Trp56Arg RAMP3 was WT in phenotype. This study provides insight into the role of these residues in RAMP3. The existence of AK222469 in the human population has implications for the function of RAMP3/GPCR complexes, particularly AM and amylin receptors.

On the occasion of the 100th issue of English Today, scholars from around the world were invited to send their thoughts. Excerpts from messages received up to September 6th, 2009 are presented here.

Human adrenomedullin (AM) is a 52-amino acid peptide belonging to the calcitonin peptide family, which also includes calcitonin gene-related peptide (CGRP) and AM2. The two AM receptors, AM(1) and AM(2), are calcitonin receptor-like receptor (CL)/receptor activity-modifying protein (RAMP) (RAMP2 and RAMP3, respectively) heterodimers. CGRP receptors comprise CL/RAMP1. The only human AM receptor antagonist (AM(22-52)) is a truncated form of AM; it has low affinity and is only weakly selective for AM(1) over AM(2) receptors. To develop novel AM receptor antagonists, we explored the importance of different regions of AM in interactions with AM(1), AM(2), and CGRP receptors. AM(22-52) was the framework for generating further AM fragments (AM(26-52) and AM(30-52)), novel AM/alphaCGRP chimeras (C1-C5 and C9), and AM/AM(2) chimeras (C6-C8). cAMP assays were used to screen the antagonists at all receptors to determine their affinity and selectivity. Circular dichroism spectroscopy was used to investigate the secondary structures of AM and its related peptides. The data indicate that the structures of AM, AM2, and alphaCGRP differ from one another. Our chimeric approach enabled the identification of two nonselective high-affinity antagonists of AM(1), AM(2), and CGRP receptors (C2 and C6), one high-affinity antagonist of AM(2) receptors (C7), and a weak antagonist selective for the CGRP receptor (C5). By use of receptor mutagenesis, we also determined that the C-terminal nine amino acids of AM seem to be responsible for its interaction with Glu74 of RAMP3. We provide new information on the structure-activity relationship of AM, alphaCGRP, and AM2 and how AM interacts with CGRP and AM(2) receptors.

Archean cratons are characterized by granite-greenstone belts, by abundant tonalites, trondhjemites, and granodiorites (TTGs), and by the presence of strong and buoyant subcratonic lithospheric mantle (SCLM). Individually, mechanisms for their formation remain controversial, and together they provide no clear picture of the tectonic style prevalent during the late Hadean and Early Archean. Following earlier observation that the dome-and-keel structure of granite-greenstone terranes resembles salt diapirs, we present numerical calculations that show that in pre-Archean to Middle Archean thermal regimes, mafic to ultramafic volcanics overlying a felsic basement will overturn diapirically in as few as 10 Ma, displacing as much as 60% of the volcanics to the lower crust. This suggests that diapirism may have dominated Hadean and Early Archean crustal tectonics. Furthermore, repeated cycles of bimodal volcanism and crustal recycling by diapirism provide a mechanism for making TTGs, leaving a restite that contributes to the SCLM from above. This diapiric tectonism later declined as the Earth cooled and plate tectonics became the dominant paradigm.

The extensive shoreline deposits of Lake Chilwa, southern Malawi, a shallow water body today covering 600 km2 of a basin of 7500 km2, are investigated for their record of late Quaternary highstands. OSL dating, applied to 36 samples from five sediment cores from the northern and western marginal sand ridges, reveal a highstand record spanning 44 ka. Using two different grouping methods, highstand phases are identified at 43.7–33.3 ka, 26.2–21.0 ka and 17.9–12.0 ka (total error method) or 38.4–35.5 ka, 24.3–22.3 ka, 16.2–15.1 ka and 13.5–12.7 ka (Finite Mixture Model age components) with two further discrete events recorded at 11.01 ± 0.76 ka and 8.52 ± 0.56 ka. Highstands are comparable to the timing of wet phases from other basins in East and southern Africa, demonstrating wet conditions in the region before the LGM, which was dry, and a wet Lateglacial, which commenced earlier in the southern compared to northern hemisphere in East Africa. We find no evidence that wet phases are insolation driven, but analysis of the dataset and GCM modelling experiments suggest that Heinrich events may be associated with enhanced monsoon activity in East Africa in both timing and as a possible causal mechanism.

The mixed semi-evergreen forests in lowland central equatorial Africa can contain many elements of secondary vegetation. This raises the question of what factors have determined the current forest composition in this region. Is this forest in the process of succession after natural climatic variation and/or anthropogenic disturbances in the past, or is it a stable forest type? This paper presents a multiproxy palaeoecological analysis of a sedimentary sequence taken from a small sedimentary basin located in logged semi-evergreen lowland forest in northern Congo-Brazzaville which addresses these questions. Analyses undertaken included fossil pollen, geochemical and microscopic charcoal. Geochemical results were interpreted as a proxy for rainfall, and showed that northern Congo has experienced changes in rainfall during the past 2580 years, while microscopic charcoal concentrations indicated increased burning from approximately 1240 cal. yr BP to the present. Analysis of the fossil pollen assemblages showed that although light-demanding taxa were a major constituent of this forest throughout the sequence, shade-tolerant taxa were more abundant in the forest prior to 1345 cal. yr BP. Increases in aridity and/or droughts after 1345 cal. yr BP, and an increase in fire after 1240 cal. yr BP resulted in a semi-evergreen forest with abundant pioneers that persisted with minor changes in composition during the last 900 years, even during a period of increased rainfall from 400 to 100 cal. yr BP. These data may guide conservation policy by predicting potential consequences of future climate change and the impact of logging. © 2009 SAGE Publications.

Receptor activity modifying protein 1 (RAMP1) is an integral component of several receptors including the calcitonin gene-related peptide (CGRP) receptor. It forms a complex with the calcitonin receptor-like receptor (CLR) and is required for receptor trafficking and ligand binding. The N-terminus of RAMP1 comprises three helices. The current study investigated regions of RAMP1 important for CGRP or CLR interactions by alanine mutagenesis. Modeling suggested the second and third helices were important in protein-protein interactions. Most of the conserved residues in the N-terminus (M48, W56, Y66, P85, N66, H97, F101, D113, P114, P115), together with a further 13 residues spread throughout three helices of RAMP1, were mutated to alanine and coexpressed with CLR in Cos 7 cells. None of the mutations significantly reduced RAMP expression. Of the nine mutants from helix 1, only M48A had any effect, producing a modest reduction in trafficking of CLR to the cell surface. In helix 2 Y66A almost completely abolished CLR trafficking; L69A and T73A reduced the potency of CGRP to produce cAMP. In helix 3, H97A abolished CLR trafficking; P85A, N86A, and F101A had caused modest reductions in CLR trafficking and also reduced the potency of CGRP on cAMP production. F93A caused a modest reduction in CLR trafficking alone and L94A increased cAMP production. The data are consistent with a CLR recognition site particularly involving Y66 and H97, with lesser roles for adjacent residues in helix 3. L69 and T73 may contribute to a CGRP recognition site in helix 2 also involving nearby residues.

The lowland region of north Norfolk contains some of the best preserved evidence for glacial deposition during the Middle Pleistocene in northwest Europe. Despite the importance of these deposits, there is limited chronological control and it is debated whether they belong to a single glaciation, equated to the Anglian Glaciation (Marine Isotope Stage 12), or represent deposition over a number of Middle Pleistocene cold stages. In order to develop an improved chronology for glaciation in this region, we obtained 18 samples for optical stimulated luminescence (OSL) dating from glacial outwash facies. Samples of coarse-grained quartz sand were measured using the SAR (single aliquot regenerative-dose) protocol. The low radioactive isotope concentrations in sediments of this region enable the traditionally accepted age limit of luminescence dating to be extended. The form of the dose response curves, pre-heat plateaux tests, and dose recovery experiments also indicate that laboratory doses can be reliably measured in these samples. Age overestimation due to partial bleaching is thought to be insignificant. The OSL ages suggest that the glacial sediments studied were deposited during MIS 12 rather than in different post MIS 12 stages.

Glaciar León is a temperate, grounded outlet of the eastern North Patagonian Icefield (NPI). It terminates at an active calving margin in Lago Leones, a 10 km long proglacial lake. We take a multidisciplinary approach to its description and use ASTER imagery and clast sedimentology to describe the geomorphology of the glacier and its associated moraines. We date periods of glacier retreat over the last 2500 years using a combination of lichenometric, dendrochronological, cosmogenic and optically stimulated luminescence techniques and show that the glacier receded from a large terminal moraine complex some 2500 years ago and underwent further significant recession from nineteenth-century moraine limits. The moraine dates indicate varying retreat rates, in conjunction with significant downwasting. The bathymetry of Lago Leones is characterized by distinct ridges interpreted as moraine ridges that dissect the lake into several basins, with water depths reaching 360 m. The fluctuations of Glaciar León appear to have been controlled by the interplay between climatic forcing and calving dynamics.

This paper presents a closed form solution for the electrical potential perturbation of a perfectly insulating flat circular disc embedded in a homogeneous half-space in a uniform primary electric field. This has applications to the detection of insulating underground targets such as hydrocarbon reservoirs or plastic mines, as well as to the electrical properties of composite materials. The solution method is an adaptation of Weber’s method for the potential around a charged conducting disk. It yields closed form analytic solutions for the electric and magnetic fields and by straightforward numerical integration, an easily evaluated numerical solution for the electric potential and an explicit solution for the electrical resistivity of a composite material consisting of a dilute concentration of such embedded disks in an otherwise uniform conductor.

Oak gallwasps (Hymenoptera, Cynipidae, Cynipini) are one of seven major animal taxa that commonly reproduce by cyclical parthenogenesis (CP). A major question in research on CP taxa is the frequency with which lineages lose their sexual generations, and diversify as purely asexual radiations. Most oak gallwasp species are only known from an asexual generation, and secondary loss of sex has been conclusively demonstrated in several species, particularly members of the holarctic genus Andricus. This raises the possibility of widespread secondary loss of sex in the Cynipini, and of diversification within purely parthenogenetic lineages. We use two approaches based on analyses of allele frequency data to test for cryptic sexual generations in eight apparently asexual European species distributed through a major western palaearctic lineage of the gallwasp genus Andricus. All species showing adequate levels of polymorphism (7/8) showed signatures of sex compatible with cyclical parthenogenesis. We also use DNA sequence data to test the hypothesis that ignorance of these sexual generations (despite extensive study on this group) results from failure to discriminate among known but morphologically indistinguishable sexual generations. This hypothesis is supported: 35 sequences attributed by leading cynipid taxonomists to a single sexual adult morphospecies, Andricus burgundus, were found to represent the sexual generations of at least six Andricus species. We confirm cryptic sexual generations in a total of 11 Andricus species, suggesting that secondary loss of sex is rare in Andricus.

The aim of this study was to investigate potential for the fixed wing Spectrem AEM system to detect perfect conductors. The methodology extends previous results in successful detection of perfect conductors in the twin helicopter Gemini AEM experiment. Primary fields in the square-wave Spectrem response are conventionally estimated by using the latest time samples in each half-cycle. Measured Spectrem aircraft attitude, coupled with physical constraints using tow-cable geometry and drag, were collectively used to devise a new primary field prediction for high altitude data. The new prediction method was then applied to survey data to produce a secondary field. Time constants predicted from the new secondary field estimation were sensitive to values 10 times greater than time constants using conventional late-time reference approach.

Large lake basins, now almost entirely devoid of water in the Kalahari’s semi arid environment, can be clearly identified from Landsat imagery of northern Botswana. These basins are delineated by a series of beach ridges marking the former shorelines of an inundated area that, at its largest extent, encompassed 60,000 km2. In the last 30 yr over 150 radiocarbon ages have been produced from three component basins that make up the Palaeo-Makgadikgadi system (consisting of the Ngami, Mababe and Makgadikgadi basins). The paucity of well preserved organic material in the region has led to these 14C ages being derived from inorganic carbonates whose open system behaviour and polygenetic origin frequently result in unreliable dates from uncertain contexts and then only within the temporal limits of the radiocarbon method. The application of Optically Stimulated Luminescence (OSL) dating to beach ridge sediments from Lake Ngami [Shaw, P.A., Bateman, M.D., Thomas, D.S.G., Davies, F., 2003. Holocene fluctuations of Lake Ngami, Middle Kalahari: chronology and responses to climatic change. Quaternary International 111 (1), 23--35] improved chronological resolution, but was limited by the use of hand dug pits. The new application of OSL to samples derived from deep coring of beach ridges has allowed access to a much longer, three dimensional, geomorphic record than previously available. Seventy-four ages new OSL ages from shorelines are presented allowing, for the first time, the opportunity to unravel the complex history of lake stages in the Ngami basin. Multiple lake highstands are identified in the period ∼ 0.3 ka to ∼ 140 ka, with several causes of these events, including tropical and local climates and upstream channel avulsion, identified. To unravel the full paleaoclimatic significance of these events it will be necessary to identify the timing of high stands in the other terminal basins within the Okavango system.

Background and purpose: Transmembrane proline (P) residues in family A G protein-coupled receptors (GPCRs) form functionally important kinks in their helices. These residues are little studied in family B GPCRs but experiments with the VPAC1 receptor and calcitonin receptor-like receptor (CL) show parallels with family A receptors. We sought to determine the function of these residues in the insert negative form of the human calcitonin receptor, a close relative of CL. Experimental approach: Proline residues within the transmembrane domains of the calcitonin receptor (P246, P249, P280, P326, P336) were individually mutated to alanine (A) using site-directed mutagenesis. Receptors were transiently transfected into Cos-7 cells using polyethylenimine and salmon and human calcitonin-induced cAMP responses measured. Salmon and human calcitonin competition binding experiments were also performed and receptor cell-surface expression assessed by whole cell ELISA. Key results: P246A, P249A and P280A were wild-type in terms of human calcitonin-induced cAMP activation. P326A and P336A had reduced function (165 and 12-fold, respectively). In membranes, human calcitonin binding was not detectable for any mutant receptor but in whole cells, binding was detected for all mutants apart from P326A. Salmon calcitonin activated mutant and wild-type receptors equally, although Bmax values were reduced for all mutants apart from P326A. Conclusions and Implications: P326 and P336 are important for the function of human calcitonin receptors and are likely to be involved in generating receptor conformations appropriate for agonist binding and receptor activation. However, agonist-specific effects were observed, implying distinct conformations of the human calcitonin receptor. British Journal of Pharmacology (2007) 151, 678–687; doi:10.1038/sj.bjp.0707246

We combine satellite gravity data from the gravity recovery and climate experiment (GRACE) and precipitation measurements from the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center’s (CPC) Merged Analysis of Precipitation (CMAP) and the Tropical Rainfall Measuring Mission (TRMM), over the period from mid-2002 to mid-2006, to investigate the relative importance of sink (runoff and evaporation) and source (precipitation) terms in the hydrological balance of the Amazon Basin. When linear and quadratic terms are removed, the time-series of land water storage variations estimated from GRACE exhibits a dominant annual signal of 250 mm peak-to-peak, which is equivalent to a water volume change of ~1,800 km3. A comparison of this trend with accumulated (i.e., integrated) precipitation shows excellent agreement and no evidence of basin saturation. The agreement indicates that the net runoff and evaporation contributes significantly less than precipitation to the annual hydrological mass balance. Indeed, raw residuals between the de-trended water storage and precipitation anomalies range from ±40 mm. This range is consistent with stream-flow measurements from the region, although the latter are characterized by a stronger annual signal than our residuals, suggesting that runoff and evaporation may act to partially cancel each other.

Summary 1 Bacillus thuringiensis (Bt) crops kill pest larvae but have led to resistance evolution in several target pests. The high dose-refuge (HDR) strategy aimed at delaying Bt resistance evolution depends on dispersal patterns of target pests. Examination of adult dispersal of the European corn borer Ostrinia nubilalis (ECB), the main target of Bt maize, can help to improve resistance management. 2 Estimated recapture rates over 20 mark–release–recapture sessions in herbaceous field borders, where ECB adults rest during the day and mate at night, were used to examine the influence of sex, release period and site on ECB dispersal. Data from an additional 30 sessions were used to test the influence of night temperature, humidity, dew index and wind speed. 3 Average recaptures within 50 m of release were lower 12 h after night (7·7%) than 12 h after day (34·5%) releases, did not differ between sexes, and decreased during nights with higher temperatures and lower wind speed. 4 Local habitat had a major influence on dispersal. The number of unmarked adults caught initially in a given section of field border was strongly correlated with those subsequently captured in the same section, suggesting that moths flying in from the surroundings consistently settle in the same preferred spots. Moreover, recapture rates of marked adults were positively correlated with the prior density of unmarked adults in the release section. 5 The spatial distribution of recaptured moths around the release point suggests that they moved on a very local scale, while those not recaptured probably left the area by a different, long-range type of dispersal. 6 Synthesis and applications. A proportion of European corn borer adults typically remained within a few metres of their initial location for at least 12 h. This should favour non-random mating early in the flight season when nights are cold, population mixture is low and most individuals are unmated. Non-random mating can accelerate the evolution of resistance, but this effect may be offset by non-random oviposition. Our findings suggest that the intensity and direction of dispersal could be manipulated by field border management. Our data on the range and prevalence of short-range dispersal and the factors influencing this process, support the view that resistance evolution is multifactorial. Our results can be used to parameterize multifactorial models from which specific management recommendations can be formulated.

To sustain viable fish populations, protect stocks of wild salmon Oncorhynchus spp., and successfully manage the Pacific salmon fishery, all sources of fishing mortality need to be understood. The fishery targeting Chinook salmon O. tshawytscha is an important component of the commercial, recreational, and First Nations fisheries in British Columbia. A mark–recovery study was used to investigate the effect of angling on both the immediate hooking mortality and subsequent spawning success of Chinook salmon in the Nicola River, British Columbia, from 1996 to 2002. The immediate hooking mortality rate was lower than mortality rates reported for marine and other freshwater fisheries. Higher hooking mortality rates were found for fish hooked in critical locations, which were associated with heavy bleeding. However, increased bleeding did not translate into reduced spawning success for those fish that survived. Conclusions regarding hook size and its association with hooking mortality rate and spawning...

Many of the small-scale arroyo systems found across southern Colorado contain well-preserved sedimentary records of prehistoric fluvial erosion and aggradation epicycles. In the following paper, we date a set of 50 ephemeral fluvial samples from four southern Colorado arroyo systems using a combination of single-grain and single-aliquot OSL techniques. Analysis of the sample D e distribution characteristics reveals that these arroyo sediments were subjected to a diverse array of bleaching conditions prior to deposition. The use of appropriate burial dose estimation procedures is therefore deemed vital to ensuring that accurate age estimates are produced for each of these samples. In this study we apply the formal ‘age model’ decision procedures of Bailey and Arnold [Statistical modelling of single-grain quartz D e distributions and an assessment of procedures for estimating burial dose. Quaternary Science Reviews, in press.] and Arnold [2006. Optical dating and computer modelling of arroyo epicycles in the American Southwest. D.phil. Thesis, University of Oxford, unpublished] to our fluvial sample dataset in order to enable a more objective selection of appropriate burial dose estimates. The resultant OSL chronostratigraphies are examined and discussed. These formal decision procedures yield sample ages that are stratigraphically consistent for 94% of the 50 fluvial samples examined. The resulting OSL ages also display a greater degree of stratigraphic consistency in comparison to those ages that would have been generated by simply applying a single type of age model to all samples.

To reduce the risk of enteric disease in poultry, knowledge of how bird gut innate defences mature with age while also responding to different rearing environments is necessary. In this study the gut innate responses of two phylogenetically distinct lines of poultry raised from hatch to 35days, in conditions mimicing high hygiene (HH) and low hygiene (LH) rearing environments, were compared. Analyses focussed on the proximal gut antimicrobial activities and the duodenal and caecal AvBD1, 4 and 10 defensin profiles. Variability in microbial killing was observed between individual birds in each of the two lines at all ages, but samples from day 0 birds (hatch) of both lines exhibited marked killing properties, Line X: 19±11% (SEM) and Line Y: 8.5±12% (SEM). By day 7 a relaxation in killing was observed with bacterial survival increased from 3 (Line Y (LY)) to 11 (Line X (LX)) fold in birds reared in the HH environment. A less marked response was observed in the LH environment and delayed until day 14. At day 35 the gut antimicrobial properties of the two lines were comparable. The AvBD 1, 4 and 10 data relating to the duodenal and caecal tissues of day 0, 7 and 35 birds LX and LY birds revealed gene expression trends specific to each line and to the different rearing environments although the data were confounded by inter-individual variability. In summary elevated AvBD1 duodenal expression was detected in day 0 and day 7 LX, but not LY birds, maintained in LH environments; Line X and Y duodenal AvBD4 profiles were detected in day 7 birds reared in both environments although duodenal AvBD10 expression was less sensitive to bird age and rearing background. Caecal AvBD1 expression was particularly evident in newly hatched birds. These data suggest that proximal gut antimicrobial activity is related to the bird rearing environments although the roles of the AvBDs in such activities require further investigation.

Most bacterial cells are enclosed in a single macromolecule of the cell wall polymer, peptidoglycan, which is required for shape determination and maintenance of viability, while peptidoglycan biosynthesis is an important antibiotic target. It is hypothesized that cellular enlargement requires regional expansion of the cell wall through coordinated insertion and hydrolysis of peptidoglycan. Here, a group of (apparent glucosaminidase) peptidoglycan hydrolases are identified that are together required for cell enlargement and correct cellular morphology of Staphylococcus aureus, demonstrating the overall importance of this enzyme activity. These are Atl, SagA, ScaH, and SagB. The major advance here is the explanation of the observed morphological defects in terms of the mechanical and biochemical properties of peptidoglycan. It was shown that cells lacking groups of these hydrolases have increased surface stiffness and, in the absence of SagB, substantially increased glycan chain length. This indicates that, beyond their established roles (for example in cell separation), some hydrolases enable cellular enlargement by making peptidoglycan easier to stretch, providing the first direct evidence demonstrating that cellular enlargement occurs via modulation of the mechanical properties of peptidoglycan., IMPORTANCE Understanding bacterial growth and division is a fundamental problem, and knowledge in this area underlies the treatment of many infectious diseases. Almost all bacteria are surrounded by a macromolecule of peptidoglycan that encloses the cell and maintains shape, and bacterial cells must increase the size of this molecule in order to enlarge themselves. This requires not only the insertion of new peptidoglycan monomers, a process targeted by antibiotics, including penicillin, but also breakage of existing bonds, a potentially hazardous activity for the cell. Using Staphylococcus aureus, we have identified a set of enzymes that are critical for cellular enlargement. We show that these enzymes are required for normal growth and define the mechanism through which cellular enlargement is accomplished, i.e., by breaking bonds in the peptidoglycan, which reduces the stiffness of the cell wall, enabling it to stretch and expand, a process that is likely to be fundamental to many bacteria.

This is the first report providing estimates of the genetic basis of breast muscle myopathies (BMM) and their relationship with growth and yield in broiler chickens. In addition, this paper addresses the hypothesis that genetic selection for increase breast yield has contributed to the onset of BMM. Data were analyzed from ongoing recording of BMM within the Aviagen breeding program. This study focused on three BMM: deep pectoral myopathy (DPM; binary trait), white striping (WS; 4 categories) and wooden breast (WB; 3 categories). Data from two purebred commercial broiler lines (A and B) were utilized providing greater than 40,000 meat quality records per line. The difference in selection history between these two lines has resulted in contrasting breast yield (BY): 29% for Line A and 21% for Line B. Data were analyzed to estimate genetic parameters using a multivariate animal model including six traits: body weight (BW), processing body weight (PW), BY, DPM, WB, and WS, in addition to the appropriate fixed effects and permanent environmental effect of the dam. Results indicate similar patterns of heritability and genetic correlations for the two lines. Heritabilities (h2) of BW, PW and BY ranged from 0.271–0.418; for DPM and WB h2

Recent studies have shown that monocytes and macrophages not only present antigens to effector T cells and stimulate and shape T cell-mediated immune responses, but they also prime naïve T cells, thus initiating adaptive immune responses. Phosphatidylinositol 3-kinase functions at an early phase of toll-like receptor signaling pathways, modulates the magnitude of the primary immune responses, and is involved in the reorganization of the actin cytoskeleton during macropinocytic and phagocytic antigen uptakes, important early steps in triggering adaptive immune responses. We assessed by flow cytometry the endocytic capacities of bovine monocytes by using endocytic tracers and

It is possible to increase the accuracy of the optical dating of some Quaternary deposits by deriving age estimates from individual quartz grains. Age estimates from individual grains within single samples display varying degrees of inconsistency however and this paper address the difficulties in reducing complex distributions of single-grain age estimates to single accurate sample ages using existing statistical age models. A modelled response of the quartz OSL signal to irradiation and illumination (both in the laboratory and under natural conditions) was used to test the accuracy of various published statistical age-models. ‘Aeolian’ and ‘fluvial’ transport conditions were simulated by adjusting the wavelength range of the daylight spectrum and the incident photon flux during the simulated bleaching event. A heterogeneous mix of grains was produced using a Monte Carlo approach, in which key irradiation and bleaching parameters were varied for each simulated grain, and the accuracy of published statistical models assessed. Results suggest that no single age-model is appropriate for all modelled cases. A formal decision process is suggested and shown to make appropriate choices between the available age-models in each of the modelled cases and in ∼85% of cases using 43 known-age sediment samples.

A Viking-Age hogback, recently discovered in the Wirral, is the smallest known example of this type of stone monument and forms part of a marked concentration of tenth- and eleventh-century carvings around the beach market at Meols. Its elaborate decoration is not only allusively Christian but visually asserts an identity with Hiberno-Norse groups in north Yorkshire.

The paper presents an application of genetic algorithms (GAs) to the problem of finding appropriate parameter values for the numerical simulation of quartz thermoluminescence (TL). We show that with the use of GAs it is possible to achieve a very good match between simulated and experimentally measured characteristics of quartz, for example the thermal activation characteristics of fired quartz. The rate equations of charge transport in the numerical model of luminescence in quartz contain a large number of parameters (trap depths, frequency factors, populations, charge capture probabilities, optical detrapping probabilities, and recombination probabilities). Given that comprehensive models consist of over 10 traps, finding model parameters proves a very difficult task. Manual parameter changes are very time consuming and allow only a limited degree of accuracy. GAs provide a semi-automatic way of finding appropriate parameters.

Only limited pharmacological characterization of the CGRP 1 receptor, a heterodimer of the calcitonin (CT) receptor-like receptor (CL) and receptor activity-modifying protein 1 has been performed in cells that do not endogenously express RAMP2. We characterized the receptor in RAMP-deficient Cos 7 cells by measuring cAMP responses following agonist treatment in the absence or presence of antagonists. Potent cAMP responses to human α-and β-CGRP (Cys(Et) 2,7 )hαCGRP and human adrenomedullin (AM) were observed. Adrenomedullin 15–52 was also an effective agonist of the CGRP 1 receptor but human and salmon calcitonin and rat amylin were only weak agonists. As expected, BIBN4096BS and CGRP 8–37 were effective antagonists of the CGRP 1 receptor. (Cys(Acm) 2,7 )hαCGRP also antagonized CGRP responses. Antagonists of related receptors were only weakly able to inhibit CGRP responses.

The English River Subprovince is a prominent belt of metasedimentary rocks in the Archean Western Superior Province. The structure of its western half was investigated by using techniques of enhancement and automatic interpretation of magnetic data, and integration of magnetic-derived information with seismic and gravity data. The results indicate that a suite of exposed felsic plutons that intruded the belt at ca. 2698 Ma extends under most of the metasedimentary rocks that are exposed at the surface. The thickness of the metasedimentary rocks is interpreted to be less than 1 km in areas where it is underlain by the members of this intrusive suite. In other areas, the metasedimentary rocks attain thicknesses of 3–4 km and appear to be underlain by rocks similar to the gneissic rocks that are exposed in the adjacent metaplutonic Winnipeg River Subprovince. The integration of enhanced magnetic data with gravity data indicates that the large gravity anomaly that extends along the English River belt correlates well spatially and morphologically with the extensive suite of felsic intrusions that underlies the belt, suggesting that the crustal component of the gravity anomaly is related to this suite of intrusions. We interpret the source of the gravity anomaly as a dense unit comprising anhydrous mineral assemblages that formed within these felsic intrusions in response to low-pressure, high-temperature metamorphism that affected the belt at ca. 2691 Ma. On the basis of geochronological, geological and geophysical constraints, we propose that this metamorphic episode is linked to the continuation of magmatism at depth after the emplacement of the ca. 2698 Ma felsic plutons, being ultimately related to the advection of mantle heat into the crust during a period of regional extension.

SUMMARY Maxwell viscoelastic materials are commonly simulated numerically in order to model the stresses and deformations associated with large-scale earth processes, such as mantle convection or crustal deformation. Both implicit and explicit time-marching methods require that the time steps used be small compared with the Maxwell relaxation time if accurate solutions are to be obtained. For crustal tectonic modelling, where Maxwell times in a ductile lower crust may be of order of a decade or less, the large number of time steps required to model processes lasting many millions of years imposes a huge computational burden. This burden is avoidable. In this paper I show that, with the appropriate formulation of the problem, time steps may be taken which are much larger than the Maxwell time without loss of accuracy, as long as they are not large compared with the times over which strain rates vary significantly (‘tectonic’ timescales) in the model. The method relies on explicit analytic integration of the Maxwell constitutive relation for the stress over time intervals, which may be longer than the relaxation time as long as they are short compared with the timescale over which crustal stresses and geometries change. The validity of the formulation is also demonstrated numerically by comparison with the analytic solutions for three simple plane-strain models: extension of a uniform block, shear of a composite layer and development of a Rayleigh‐Taylor instability.

For the red TL of quartz extracted from Chinese loess, the single-aliquot regenerative-dose (SAR) procedure overestimates the known laboratory doses in dose recovery test. The overestimation is the result of the first heating during the measurement of natural TL signal causing a sensitivity reduction, which is not corrected for using a SAR protocol. The SARA procedure was used to measure the sensitivity change. Using this as a correction factor is tested by comparison with the quartz optically stimulated luminiscence (OSL) equivalent dose. SARA is also employed to determine the residual level of red TL, which is found to be more than 100 Gy.

Date of Acceptance: 23/05/2014 We define three types of neighbour-balanced designs for experiments where the units are arranged in a circle or single line in space or time. The designs are balanced with respect to neighbours at distance one and at distance two. The variants come from allowing or forbidding self-neighbours, and from considering neighbours to be directed or undirected. For two of the variants, we give a method of constructing a design for all values of the number of treatments, except for some small values where it is impossible. In the third case, we give a partial solution that covers all sizes likely to be used in practice. Postprint

The zoonotic association between Campylobacter bacteria in poultry and humans has been characterized by decades of research which has attempted to elucidate the epidemiology of this complex relationship and to reduce carriage within poultry. While much work has focused on the mechanisms facilitating its success in contaminating chicken flocks (and other animal hosts), it remains difficult to consistently exclude Campylobacter under field conditions. Within the United Kingdom poultry industry, various bird genotypes with widely varying growth rates are available to meet market needs and consumer preferences. However, little is known about whether any differences in Campylobacter carriage exist across this modern broiler range. The aim of this study was to establish if a relationship exists between growth rate or breed and cecal Campylobacter concentration after natural commercial flock Campylobacter challenge. In one investigation, four pure line genotypes of various growth rates were grown together, while in the second, eight different commercial broiler genotypes were grown individually. In both studies, the Campylobacter concentration was measured in the ceca at 42 days of age, revealing no significant difference in cecal load between birds of different genotypes both in mixed- and single-genotype pens. This is important from a public health perspective and suggests that other underlying reasons beyond genotype are likely to control and affect Campylobacter colonization within chickens. Further studies to gain a better understanding of colonization dynamics and subsequent proliferation are needed, as are novel approaches to reduce the burden in poultry.

Resetting of previously accumulated optically stimulated luminescence (OSL) signals during transport of sediment is a fundamental requirement for reliable optical dating. The completeness of optical resetting of 46 modern-age quartz samples from a variety of depositional environments was examined. All equivalent dose ( D e ) estimates were 5 Gy , with the majority of aeolian samples 0.1 Gy , and fluvial samples 1 Gy . The OSL signal of quartz originates from several trap types with different rates of charge loss during illumination. As such, incomplete bleaching may be identifiable as an increase in D e from easy-to-bleach through to hard-to-bleach components. For all modern fluvial samples with non-zero D e values, SAR D e ( t ) analysis and component-resolved linearly modulated OSL (LM OSL) D e estimates showed this to be the case, implying incomplete resetting of previously accumulated charge. LM OSL measurements were also made to investigate the extent of bleaching of the slow components in the natural environment. In aeolian sediments examined, the natural LM OSL was effectively zero (i.e. all components were fully reset). The slow components of modern fluvial samples displayed measurable residual signals up to 15 Gy.

An essential part of the laboratory procedure associated with optical dating is the irradiation of sample aliquots with known doses of ionizing radiation. Only if laboratory irradiation faithfully reproduces the effects (within the dating sample) of natural irradiation (during burial) will the dates obtained be accurate. Modelling of quartz luminescence suggests that the usual practice of administering laboratory doses at room temperature, and in single exposures, may lead to both equivalent-dose overestimation and increased levels of scatter in individual age estimates for samples with palaeodoses greater than ∼ 40 Gy. In the model, this effect is due to the large differences between laboratory and natural dose rates. A modification to standard irradiation practices is suggested as a remedy to this problem, whereby laboratory regeneration doses are administered in 10 Gy pulses, with the aliquot then being heated to 240 °C following each pulse. Empirical measurements of 12 sedimentary samples support the theoretical findings, with significant differences in dose response being observed between single-irradiation and pulsed-irradiation OSL regeneration data. Results are also presented in which the problem of the laboratory dose response failing to reach the level obtained through natural irradiation is remedied by the pulsed-irradiation procedure. It is possible that the application of pulsed-irradiation regeneration may in future lead to a more accurate means of dating the deposition of quaternary sediments, although this remains to be demonstrated empirically by the dating of known-age samples.

Magnetotelluric (MT) soundings were made at more than 230 sites in the western Superior Province, in central Canada, as part of the Lithoprobe Western Superior Transect investigations. The Superior Province forms the nucleus of the North American continent. Its western part contains a regional pattern of east–west trending 100–200 km wide granite–greenstone and metasedimentary belts or subprovinces. The objectives of the MT study are to define the electrical resistivity structure of the crust of the subprovinces and their boundaries, and to determine if there exists a signature in the upper mantle related to the formation of the craton. The exceptionally large MT database for the western Superior Province provides a three-dimensional sampling of the resistivity structure. In this paper, the primary MT responses from the data set, including geoelectric strike, apparent resistivity and phase, are used to define first-order geoelectrical structures in the region. Apparent resistivity responses indicate the ca 3.0 Ga North Caribou terrane contains extremely resistive crust. Crust to the south, accreted at ca. 2.7 Ga, is significantly more conductive, with resistivities similar to in the southeast Superior Province. The results suggest that the supracrustal component of the North Caribou terrane provides minimal enhancement of the crustal conductivity. At the southern margin of the former North Caribou superterrane, induction arrows define a conductivity anomaly that extends in an east–west direction for at least 600 km and causes a reversal of arrows in a region 100–200 km wide. This anomaly is interpreted to be caused by a conductive component of the 2.7 Ga metasedimentary rocks of the English River subprovince. The observations demonstrate the ability of electromagnetic methods to map some Neoarchean continental margins. In the southwest Superior Province, geoelectric strike azimuths for periods corresponding to signal penetration into the upper mantle are aligned with the trend of subprovince boundaries and are interpreted to be related to fossil structure in the mantle lithosphere. This result provides support to the interpretation that the lithospheric mantle of the western Superior Province has remained intact since the 2.7 Ga accretion of the subprovinces. The MT responses from the western Superior Province have thus defined a number of large-scale resistivity structures providing information on tectonic structure and history, and confirming the value of electromagnetic imaging of Archean lithosphere.

United Technologies Corporation is developing a low-cost solid oxide fuel cell stack technology that offers long-life durability and thermal cycling robustness for building cooling heating and power applications. Our design philosophy decouples the coefficient of thermal expansion and oxidation requirements for metallic interconnects, enabling us to use oxidation resistant nickel-based superalloy interconnects. Innovative interconnect designs along with non-contaminating seals offer tremendous advantages in producing long-life, thermal cycle tolerant stacks. 1-cell and 3-cell stack tests for up to 4500 hours and 20 thermal cycles show excellent stack durability.

The Australian Medical Journal is important to Australian anaesthesia in that, as well as associated editorials, it recorded the first use of ether for surgical operations. Though it survived from 1 August 1846 until 1 October 1847, its first issue was surrounded with mystery, referring to an earlier publication. Proof of this earlier issue of April 1846 has been discovered though no copy remains extant.

A theoretical model of quartz luminescence is presented and used to simulate luminescence response to environmental dose rates over geological timescales. Simulations of natural burial and laboratory measurements suggest that dose-rate effects in quartz cause systematic overestimation of absorbed doses when standard dating procedures are applied. Overestimation of absorbed dose (and therefore of age estimates) becomes significant at palaeodoses greater than ∼40 Gy . This effect is due to competition from the relatively thermally unstable R1 recombination centre (the centre that also plays a key role in ‘dose quenching’ of quartz optically stimulated luminescence, and thermoluminescence). Variation in the concentration of R1 centres leads to variation in measured equivalent dose (De) values and may potentially be a significant source of scatter in De estimates from sedimentary quartz samples. Model predictions indicate that by administering laboratory doses either at raised temperature, or in short pulses with intervening thermal treatments, the malign effects of the R1 centre can be removed. Results from laboratory measurements using pulsed-irradiation support the theoretical predictions. Implementation of pulsed irradiation in a single-aliquot regenerative-dose procedure yielded an accurate and more precise age estimate for a last-interglacial age dune deposit from Africa, compared to the overestimate obtained using the standard procedure, as predicted by the model.

We present an adaptation of the full multigrid algorithm in DC resistivity modelling in an effort to increase its accuracy. There is a great difficulty with conventional multigrid solvers in representing the physics of an arbitrary distribution of electrical conductivity on a very coarse grid. In general, conventional rectangular finite-difference or 5-point approximations of Poisson's equation cannot represent, at a coarse grid level, the effective anisotropy on a coarse scale which results from fine structure in the model. An exception to this generalization occurs when the principal axes of structural anisotropy are aligned with the coordinate axis. Additional and similarly generated problems arise when a coarse cell is obliged to represent fine structure containing very high conductivity contrasts. We have developed an adaptation of the usual resistive-network representation of the continuum, which avoids some of these problems, and have compared it with the traditional resistive network currently used. The network adaptation consists of replacing the usual 5-point Laplacian operator stencil used on the finite-difference grid with a 9-point stencil, and the conductivity scalar with a 6-parameter conductivity parametrization. This parametrization permits representation of arbitrarily orientated anisotropy as well as more complex behaviour related to high conductivity contrasts. The importance of multigrid solvers does not lie in their speed at forward modelling (which is comparable with other methods), but rather in their potential for inverse modelling. Inverse solvers which proceed by refinement of an initially very coarse solution can, in principle, take time only linearly proportional to the number of gridpoints in the final desired model.

Kistler Aerospace Corporation is developing the K-1, a fully reusable, two-stage-to-orbit launch vehicle. Both stages return to the launch site using parachutes and airbags. Initial flight operations will occur from Woomera, Australia. K-1 guidance is performed autonomously. Each stage of the K-1 employs a triplex, fault tolerant avionics architecture, including three fault tolerant computers and three radiation hardened Embedded GPS/INS units with a hardware voter. The K-1 has an Integrated Vehicle Health Management (IVHM) system on each stage residing in the three vehicle computers based on similar systems in commercial aircraft. During first-stage ascent, the IVHM system performs an Instantaneous Impact Prediction (IIP) calculation 25 times per second, initiating an abort in the event the vehicle is outside a predetermined safety corridor for at least 3 consecutive calculations. In this event, commands are issued to terminate thrust, separate the stages, dump all propellant in the first-stage, and initiate a normal landing sequence. The second-stage flight computer calculates its ability to reach orbit along its state vector, initiating an abort sequence similar to the first stage if it cannot. On a nominal mission, following separation, the second-stage also performs calculations to assure its impact point is within a safety corridor. The K-1's guidance and control design is being tested through simulation with hardware-in-the-loop at Draper Laboratory. Kistler's verification strategy assures reliable and safe operation of the K-1.

Bleaching spectra of the ‘fast’ and ‘medium’ optically stimulated luminescence (OSL) components of quartz are reported. A dependence of photoionization cross-section, σ, on wavelength was observed for the fast and medium components and a significant difference in their responses to stimulation wavelength was found. The ratio of the fast and medium photoionization cross-sections, σfast/σmedium, varied from 30.6 when stimulated with View the MathML source light to 1.4 at View the MathML source. At View the MathML source the fast and medium photoionization cross-sections were found to be sufficiently different that infrared bleaching at raised temperatures allowed the selective removal of the fast component with negligible depletion of the medium. A method for optically separating the OSL components of quartz is suggested, based on the wavelength dependence of photoionization cross-sections.

The Sahelian Margin of West Africa is widely recognised as an area of recent environmental catastrophe and human suffering arising from food shortage and land degradation associated with prolonged drought. The propensity of this region to suffer drought has been related, using environmental data collected during the period of instrumental records, to a combination of low mean annual rainfall levels and a high degree of rainfall variability which relates to sea surface temperature anomalies in the adjacent tropical Atlantic Ocean. Despite the significant environmental and human consequences of such droughts, there is a paucity of long-term environmental data for the West African Sahel. Aeolian dune reactivations in this area are a potentially highly useful environmental archive of past periods of extended drought conditions, which may have resulted in localised or widespread dune reactivation. Here we describe the initial results from an ongoing programme of research, which seeks to develop a detailed record of past dune reactivations in Mali. We find evidence for repeated Holocene dune reactivation events and a significant number of reactivations, which commenced at the time of onset of the last major drought cycle in the early 1970s. We obtain ages as young as 20–30 years for some significant dune units (thickness up to 1 m) and describe the results of experiments which test the performance of our dating exercise. We specifically test for the significance of preheat temperature on single aliquot regeneration (SAR) equivalent dose determinations and recycling ratios; neither are found vary significantly as a function of preheating. Optical dating of sand sized quartz could provide a useful tool for palaeogeographical mapping of ancient and historical dune reactivations in this region and elsewhere.