A New Evolutionary Channel for Type Ia Supernovae

We show that long-period dwarf novae offer a promising route for making Type Ia supernovae. For typical dwarf nova duty cycles d ~ 0.1 - 0.01, mass is accreted by the white dwarf mainly during dwarf nova outbursts at rates allowing steady nuclear burning of most of the accreted matter. Mass gains up to ~ 0.4 Msun are possible in this way. Although these are too small to allow a 0.7 Msun WD to reach the Chandrasekhar mass, they are sufficient if the WD grew to ~ 1 Msun in a previous episode of thermal-timescale mass transfer, i.e. for those long-period dwarf novae which descend from supersoft binaries. A further advantage of this picture is that the supernova always occurs in a binary of small secondary/primary mass ratio, with the secondary having very little remaining hydrogen. Both features greatly reduce the possibility of hydrogen contamination of the supernova ejecta.Comment: 5 pages, 5 figures, MNRAS, accepte

Sport psychology consulting in professional rugby union in the United Kingdom

This article describes my experiences of working within professional rugby union in South Wales, United Kingdom. Initially, I locate the context of professional rugby union in the country alongside how my various subcultural understandings of the sport were obtained. After outlining my consulting philosophy developed for working in a professional rugby union context, subsequent cultural challenges for practitioners working in the sport are then explored, together with example strategies used to account for such cultural considerations. I conclude by reflecting upon the importance of practitioners possessing and developing contextual intelligence and cultural competency to work effectively in high performance environments

The Charging Structure for the Great Barrier Reef - A review of willingness to pay

The Great Barrier Reef Marine Park Authority (GBRMPA or the Reef Authority) is currently conducting a comprehensive review of the charging structure for the use of the Great Barrier Reef (GBR) Marine Park with a view to implement potential changes from 1 July 2023

Using the factors of soil formation to assess stable carbon isotope disequilibrium in late Pleistocene (MIS 3) buried soils of the Great Plains, North America

The stable carbon isotope composition of both soil organic matter (SOM) and pedogenic carbonate are widely used as paleoenvironmental proxies. This study utilizes δ13C analyses to reconstruct bioclimatic change from a series of buried soils in the central Great Plains of North America that developed between ca. 44–24 ka. Results revealed a paradoxical isotopic disequilibrium between the isotopic composition of bulk SOM (δ13CSOM) and pedogenic carbonate (δ13Ccarb). Specifically, Δ13C values are 0.1 to 6.3 per mil greater than the highest expected equilibrium value of 17 per mil in the Bk horizons. In contrast, Δ13C values are 0.1 to 4.8 per mil lower than the lowest expected equilibrium value of 14 per mil in the Ak horizons. A soil-forming factor approach was utilized to establish multiple working hypotheses regarding the influence of climate, vegetation, parent material, and time on the observed isotopic disequilibrium. Of the various hypotheses presented, we suggest that the following most likely explain the observed isotopic disequilibrium. The greater-than-expected Δ13C values in the Bk horizons most likely reflects seasonal bias in pedogenic carbonate formation, resulting in an apparent C4-biased signal. The lower-than-expected Δ13C values in the Ak horizons remains perplexing. The most likely explanation is that detrital carbonate contributions affected the δ13Ccarb record or that the δ13Ccarb and δ13CSOM records are asynchronous. Overall, it appears that different factors have affected the δ13CSOM and δ13Ccarb records independently and therefore results of this study highlight the importance of assessing pedogenic carbonates for isotopic equilibrium as well as the need to understand past environmental conditions (i.e., soil-forming factors) when interpreting isotopic trends

Green tea polyphenols in cardiometabolic health: A critical appraisal on phytogenomics towards personalized green tea

Cardiovascular disease is a chronic multifactorial health complication that is either directly or indirectly associated with pathophysiological mechanisms, including pro-oxidation, pro-inflammation, vascular and endothelial dysfunction, impaired platelet function, thrombosis, and others. The therapeutic options to circumvent cardiovascular complications include several phytomedicines, including green tea polyphenols. However, while many experimental and clinical studies report distinct mechanisms by which the polyphenols of green tea elicit a beneficial role in cardiometabolic health, the translation and applications of green tea polyphenols in clinics have yet to gain their optimal use on the broader population. This review critically appraises the various reported mechanisms of green tea polyphenols in modulating cardio-metabolic health and associated phyto-genomic challenges. Further, our review highlights the probability of gene polymorphic associated therapeutic variations in individuals using green tea for cardio-metabolic effects and the necessity to personalize green tea for clinical use, thereby improvising the risk-benefit ratio

A model of superoutbursts in binaries of SU UMa type

A new mechanism explaining superoutbursts in binaries of SU UMa type is proposed. In the framework of this mechanism the accretion rate increase leading to the superoutburst is associated with formation of a spiral wave of a new "precessional" type in inner gasdynamically unperturbed parts of the accretion disc. The possibility of existence of this type of waves was suggested in our previous work (astro-ph/0403053). The features of the "precessional" spiral wave allow explaining both the energy release during the outburst and all its observational manifestations. The distinctive characteristic of a superoutburst in a SU UMa type star is the appearance of the superhump on the light curve. The proposed model reproduces well the formation of the superhump as well as its observational features, such as the period that is 3-7% longer than the orbital one and the detectability of superhumps regardless of the binary inclination.Comment: LaTeX, 20 pages, 4 figures, to be published in Astron. Z

Quaternary Stratigraphy and Stratigraphic Nomenclature Revisions in Kansas

This paper outlines Quaternary nomenclature changes to Zeller (1968) that have been adopted by the Kansas Geological Survey (KGS). The KGS formally recognizes two series/epochs for the Quaternary: the Holocene and Pleistocene. Pleistocene stage/age names Kansan, Aftonian, Nebraskan, and Yarmouthian are abandoned and replaced with the broader term "pre-Illinoian." Formation names Bignell, Peoria, Gilman Canyon, and Loveland are maintained for loess units. Formation names for the following alluvial lithostratigraphic units are abandoned: Crete, Sappa, Grand Island, Fullerton, and Holdrege. The Severance Formation is adopted as a new lithostratigraphic unit for thick packages of late Pleistocene alluvium and colluvium in Kansas. The DeForest Formation is accepted as a valid lithostratigraphic unit for deposits of fine-grained Holocene alluvium in Kansas. Formation names Iowa Point, Nickerson, and Cedar Bluffs for glacial tills and Atchison and David City for glaciofluvial deposits are abandoned. The Afton and Yarmouth Soils are abandoned as pedostratigraphic units, whereas the Sangamon Geosol and Brady Geosol are maintained

Foundations of character: methodological aspects of a study of character development in three- to six-year-old children with a focus on sharing behaviours

This article focuses on methodological issues arising in a study of character development, using illustrations of ‘sharing behaviours.’ Based primarily in six early years settings in southeast England the research records naturalistic observations of peer interactions for 55 children aged three to six years. Applying grounded theory to the processes of observing, analysing and interpreting evidence required a cautious and collectively reflective approach. The methodology sought to moderate the influence of the researchers' prior knowledge of ‘grand theories’ of moral development and assumptions about relevance to the observation records. The study's originality lay in the exploration of moral development without reference to any particular grand theory as an explanatory framework; and in the reluctance to be drawn to potentially simplistic rationalisations of the children's intentions on the basis of their observed behaviours. Exploring young children's subjective experiences, this research provides insights into the intricacy of this process, steering away from ‘neat’ findings and attempting to reflect the sophistication of the children's skilful and sometimes surprising negotiations of moral dilemmas. Implications for practice relate to the complexities involved in attempts to unravel the developing moral characters of young children and the practice through which this may be nurtured