The Neogene seismic stratigraphy and uplift history of the Otago Shelf, New Zealand

The Otago continental shelf is a prospective petroleum area on the east side of the South Island New Zealand. During the Neogene it evolved from a post-rift to passive margin as giant progrades extended eastward across the shelf, fed by tectonic uplift and erosion of the Southern Alps to the west. Seismic reflection profiles reveal an uplifted limestone horizon near the Dunedin Volcano. This may be caused by a buoyant load under the lithosphere and can be spatially and temporally linked to the Dunedin Volcano and geophysical anomalies in the area. This thesis utilises 2D and 3D seismic data to map Neogene sequence boundaries over the Otago Shelf. Seven such sequence boundaries have been mapped based on distinctive seismic characteristics above and below these surfaces. These surfaces have been tied to nearby petroleum and Integrated Ocean Drilling Project wells using biostratigraphic data and then used to generate a series of isopach and depth maps that document the Neogene evolution of this margin. The maps depict the deposition of Neogene sediment and provide age constraints to structural events in the basin such as the uplift near Dunedin and fault movement on the Endeavour High. The maps are then used to develop a lithospheric flexure model where uplift is interpreted to have been caused by asthenospheric upwelling beneath Dunedin. The model provides insight into the conditions that led to the flexure of the lithosphere, specifically the elastic thickness of the plate and the magnitude and depth distribution of buoyant intrusive material that fed the Dunedin Volcano. Asthenospheric upwelling explains elevated heat flow around Dunedin and would result in enhanced petroleum maturity. This highlights the potential for petroleum generation in source rocks immediately offshore from Dunedin

Viral inosine triphosphatase: A mysterious enzyme with typical activity, but an atypical function

Plant viruses typically have highly condensed genomes, yet the plant‐pathogenic viruses Cassava brown streak virus, Ugandan cassava brown streak virus, and Euphorbia ringspot virus are unusual in encoding an enzyme not yet found in any other virus, the “house‐cleaning” enzyme inosine triphosphatase. Inosine triphosphatases (ITPases) are highly conserved enzymes that occur in all kingdoms of life and perform a house‐cleaning function by hydrolysing the noncanonical nucleotide inosine triphosphate to inosine monophosphate. The ITPases encoded by cassava brown streak virus and Ugandan cassava brown streak virus have been characterized biochemically and are shown to have typical ITPase activity. However, their biological role in virus infection has yet to be elucidated. Here we review what is known of viral‐encoded ITPases and speculate on potential roles in infection with the aim of generating a greater understanding of cassava brown streak viruses, a group of the world's most devastating viruses

Cassava brown streak virus Ham1 protein hydrolyses mutagenic nucleotides and is a necrosis determinant

Cassava brown streak disease (CBSD) is a leading cause of cassava losses in East and Central Africa and is currently having a severe impact on food security. The disease is caused by two viruses within the Potyviridae family: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), which both encode atypical Ham1 proteins with highly conserved ITP pyrophosphohydrolase (ITPase) domains. ITPase proteins are widely encoded by plant, animal and archaea. They selectively hydrolyse mutagenic nucleotide triphosphates (NTP) to prevent their incorporation into nucleic acid and thereby function to reduce mutation rates. It has previously been hypothesised that U/CBSVs encode Ham1 proteins with ITPase activity to reduce viral mutation rates during infection. In this study, we investigate the potential roles of U/CBSV Ham1 proteins. We show that both CBSV and UCBSV Ham1 proteins have ITPase activities through in vitro enzyme assays. Deep-sequencing experiments found no evidence of the U/CBSV Ham1 proteins providing mutagenic protection during infections of Nicotiana hosts. Manipulations of the CBSV Tanza infectious clone were performed, including a Ham1 deletion, ITPase point mutations and UCBSV Ham1 chimera. Unlike severely necrotic wild-type CBSV Tanza infections, infections of Nicotiana benthamiana with the manipulated CBSV ICs do not develop necrosis, indicating that that the CBSV Ham1 is a necrosis determinant. We propose that the presence of U/CBSV Ham1 proteins with highly conserved ITPase motifs indicates that they serve highly selectable functions during infections of cassava and may represent a Euphorbia host adaptation that could be targeted in anti-viral strategies

Are children's own interpretations of ambiguous situations based on how they perceive their mothers have interpreted ambiguous situations for them in the past?

The intergenerational transmission of anxious cognitions and behaviors may be a possible mechanism underlying concordance between maternal and child anxieties. By disambiguating ambiguous situations for their child in a threatening manner, anxious mothers may `train their children towards a general tendency to also interpret ambiguity in a threatening way. Ninety-two children and their mothers completed trait anxiety measures. Children completed two ambiguous scenario questionnaires, to measure their own interpretations of ambiguous situations (ASQ-C) and to measure their expectations of their mother's interpretation and behavior in response to ambiguous situations involving them (ASQ-EM). Maternal and child anxiety were significantly correlated. Children who made threat interpretations also anticipated that their mother would disambiguate situations for them in a threatening way. The relationship between maternal anxiety and child threat cognitions was mediated by children's expectations of how their mother would disambiguate situations for them when taken together with children's trait anxiety. The present findings provide preliminary support for the suggestion that children of anxious mothers may learn to interpret and respond to ambiguous situations based on how their mothers have interpreted ambiguous situations for them in the past

Oxidation Behavior Of Graphene Nanoplatelet Reinforced Tantalum Carbide Composites In High Temperature Plasma Flow

Graphene nanoplatelets (GNP) reinforced tantalum carbide (TaC) composites are exposed to a high temperature plasma flow in order to evaluate the effects of GNP on the oxidation behavior of TaC at conditions approaching those of hypersonic flight environments. The addition of GNP is found to suppress the formation of the oxide layer by up to 60%. The high thermal conductivity of GNPs dissipates heat throughout the sample thereby reducing thermal gradients and reducing the intensity of heating at the surface exposed to plasma. In addition, GNPs enhance oxidation resistance by providing toughening which suppresses crack formation and bursting that accelerates oxidation. Scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HR-TEM) reveal that GNPs have the ability to survive the intense high temperature of the plasma. GNPs are believed to seal oxide grain boundaries and hinder the further influx of oxygen. GNPs also provide nano sized carbon needed to induce the localized reduction of Ta2O5 to TaC. Micro computed X-ray tomography (MicroCT) validates that the above mechanisms protect the underlying unoxidized material from the structural damage caused by thermal shocks and high shear forces, by reducing thermal gradients and providing toughness. © 2013 Elsevier Ltd. All rights reserved

How age and sex affect treatment outcomes for children with severe malnutrition: A multi‐country secondary data analysis

International audienceAge and sex influence the risk of childhood wasting. We aimed to determine if wasting treatment outcomes differ by age and sex in children under 5 years, enroled in therapeutic and supplementary feeding programmes. Utilising data from stage 1 of the ComPAS trial, we used logistic regression to assess the association between age, sex and wasting treatment outcomes (recovery, death, default, non-response, and transfer), modelling the likelihood of recovery versus all other outcomes. We used linear regression to calculate differences in mean length of stay (LOS) and mean daily weight gain by age and sex. Data from 6929 children from Kenya, Chad, Yeme

Decolonising imperial heroes:Britain and France

The heroes of the British and French empires stood at the vanguard of the vibrant cultures of imperialism that emerged in Europe in the second half of the nineteenth century. Yet imperial heroes did not disappear after 1945 as British and French flags were lowered around the world. On the contrary, their reputations underwent a variety of metamorphoses in both the former metropoles and the former colonies. The introduction to this special issue of the Journal of Imperial and Commonwealth History presents an overview of the changing history and historiography of imperial heroes half a century after the end of empire