A Feasibility Study of Airborne Radiometric Survey for UK Fallout

Brief details are presented of a feasibility study of the use of aerial radiometric survey techniques to map local variations of fallout and natural radioactivity in Scotland

A Feasibility Study of Airborne Radiometric Survey for UK Fallout

Brief details are presented of a feasibility study of the use of aerial radiometric survey techniques to map local variations of fallout and natural radioactivity in Scotland

What is the origin of the Scottish populations of the European endemic Cherleria sedoides (Caryophyllaceae)?

Cherleria sedoides L. (Minuartia sedoides (L.) Hiern) is a montane perennial which, with some species in Minuartia sect. Spectabiles, is more closely related to Scleranthus than to other Minuartia species and is therefore best restored to the reinstated and redefined genus Cherleria. Reconstruction of the ancestral area of the clade containing C. sedoides suggests that it evolved in the Alps or the Balkan peninsula. The species now has an unusual distribution, being present in the mountains of southern Europe and Scotland but absent from the Arctic. Three historical scenarios that might have led to the presence of the species in Scotland are outlined and tested by a molecular analysis comparing Scottish populations with populations from the Pyrenees and the Alps. The sampled populations show little variation in internal transcribed spacer (ITS)/external transcribed spacer (ETS) but much more in cpDNA. The latter reveals a major division between some Alpine material and the other Alpine, Pyrenean and Scottish plants. Once the anomalous Alpine haplotypes are excluded, Scottish populations are at least as variable as those from the Alps and Pyrenees, and are closely related to both. We conclude that they have not undergone a long period of isolation, nor have they originated by recent, long-distance dispersal from the Alps or Pyrenees. They appear to be derived from a metapopulation that was probably widespread at the last glacial maximum (LGM) and gave rise to the Alpine, Pyrenean and Scottish plants

Protein-quality evaluation of complementary foods in Indian children

Background: The types of food in complementary feeding of infants and young children are important for growth and development. Food protein quality, as measured by the Digestible Indispensable Amino Acid Score (DIAAS), requires the determination of true ileal digestibility of indispensable amino acids (IAAs) in children. Objectives: First, the aim of this study was to measure the true ileal IAA digestibility of 4 (rice, finger millet, mung bean, and hen egg) commonly consumed complementary foods in children aged <2 y using the dual-isotope tracer method. Second, we calculated the DIAAS of complementary feeding diets and their relation to stunting in a representative Indian rural population. Design: Rice, finger millet, and mung bean were intrinsically labeled with deuterium oxide (2H2O), whereas egg was labeled through oral dosing of hens with a uniformly 2H-labeled amino acid mixture. True ileal IAA digestibility was determined by the dual-isotope tracer technique. The DIAAS of complementary food protein was calculated in children aged 1–3 y from a nationally representative survey to evaluate its relation with stunting. Results: True ileal IAA digestibility was lowest in mung bean (65.2% ± 7.1%), followed by finger millet (68.4 %± 5.3%) and rice (78.5% ± 3.5%), and was highest for egg (87.4% ± 4.0%). There was a significant inverse correlation of complementary food DIAAS with stunting in survey data (r = −0.66, P = 0.044). The addition of egg or milk to nationally representative complementary diets theoretically improved the DIAAS from 80 to 100. Conclusions: The true ileal IAA digestibility of 4 foods commonly consumed in complementary diets showed that the DIAAS was associated with stunting and reinforces the importance of including animal source food (ASF) in diets to improve growth. This trial was registered at http://ctri.nic.in/clinicaltrials/login.php as CTRI/2017/02/007921

Modification of alumina matrices through chemical etching and electroless deposition of nano-Au array for amperometric sensing

Simple nanoporous alumina matrix modification procedure, in which the electrically highly insulating alumina barrier layer at the bottom of the pores is replaced with the conductive layer of the gold beds, was described. This modification makes possible the direct electron exchange between the underlying aluminum support and the redox species encapsulated in the alumina pores, thus, providing the generic platform for the nanoporous alumina sensors (biosensors) with the direct amperometric signal readout fabrication

The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets

This review addresses our current understanding of comets that venture close to the Sun, and are hence exposed to much more extreme conditions than comets that are typically studied from Earth. The extreme solar heating and plasma environments that these objects encounter change many aspects of their behaviour, thus yielding valuable information on both the comets themselves that complements other data we have on primitive solar system bodies, as well as on the near-solar environment which they traverse. We propose clear definitions for these comets: We use the term near-Sun comets to encompass all objects that pass sunward of the perihelion distance of planet Mercury (0.307 AU). Sunskirters are defined as objects that pass within 33 solar radii of the Sun’s centre, equal to half of Mercury’s perihelion distance, and the commonly-used phrase sungrazers to be objects that reach perihelion within 3.45 solar radii, i.e. the fluid Roche limit. Finally, comets with orbits that intersect the solar photosphere are termed sundivers. We summarize past studies of these objects, as well as the instruments and facilities used to study them, including space-based platforms that have led to a recent revolution in the quantity and quality of relevant observations. Relevant comet populations are described, including the Kreutz, Marsden, Kracht, and Meyer groups, near-Sun asteroids, and a brief discussion of their origins. The importance of light curves and the clues they provide on cometary composition are emphasized, together with what information has been gleaned about nucleus parameters, including the sizes and masses of objects and their families, and their tensile strengths. The physical processes occurring at these objects are considered in some detail, including the disruption of nuclei, sublimation, and ionisation, and we consider the mass, momentum, and energy loss of comets in the corona and those that venture to lower altitudes. The different components of comae and tails are described, including dust, neutral and ionised gases, their chemical reactions, and their contributions to the near-Sun environment. Comet-solar wind interactions are discussed, including the use of comets as probes of solar wind and coronal conditions in their vicinities. We address the relevance of work on comets near the Sun to similar objects orbiting other stars, and conclude with a discussion of future directions for the field and the planned ground- and space-based facilities that will allow us to address those science topics

Contribution of humic substances from different composts to the synthesis of humin in a tropical soil

The contribution of humic substances of different composts to the synthesis of humin in a tropical soil was evaluated. Increasing doses (0, 13, 26, 52, and 104 Mg ha-1) of five different composts consisting of agroinpowderrial residues were applied to a Red-Yellow Latosol. These composts were chemically characterized and 13C NMR determined and the quantity of the functional alkyl groups of humic acids applied to the soil as compost was estimated. Thirty days after application of the treatments, organic matter samples were collected for fractionation of humic acids (HA), fulvic acids (FA) and humin (HU), from which the ratios HA/FA and (HA + FA)/HU were calculated. The application of the composts based on castor cake resulted in the highest HU levels in the soil; alkyl groups of the HA fraction of the composts were predominant in the organic components added to the HU soil fraction.Avaliou-se a contribuição de substâncias húmicas provenientes de diferentes compostos orgânicos na síntese de humina em um solo tropical. Para isso, foram adicionadas doses crescentes (0, 13, 26, 52 e 104 Mg ha-1) de cinco diferentes compostos orgânicos formulados com resíduos orgânicos agroindustriais em um Latossolo Vermelho-Amarelo. As substâncias húmicas desses compostos foram caracterizadas quimicamente e por ressonância nuclear magnética do 13C, sendo estimados os quantitativos dos grupos funcionais alquil dos ácidos húmicos aplicados no solo via composto. Trinta dias após aplicação dos tratamentos, coletaram-se amostras de solo para fracionamento da matéria orgânica em ácidos húmicos (AH), ácidos fúlvicos (FA) e humina (HU), a partir dos quais foram calculadas as relações AH/FA e (AH + FA)/HU. A aplicação do composto à base de torta de mamona contribuiu para obtenção de teores mais elevados de HU no solo; a incorporação de componentes orgânicos à fração HU do solo foi regida pelo conteúdo de grupos alquil da fração AH dos compostos