Interaction of water, hydrogen and their mixtures with SnO2 based materials: the role of surface hydroxyl groups in detection mechanisms

DRIFTS, TGA and resistance measurements have been used to study the mechanism of water and hydrogen interaction accompanied by a resistance change (sensor signal) of blank and Pd doped SnO2. It was found that a highly hydroxylated surface of blank SnO2 reacts with gases through bridging hydroxyl groups, whereas the Pd doped materials interact with hydrogen and water through bridging oxygen. In the case of blank SnO2 the sensor signal maximum towards H-2 in dry air (R-0/R-g) is observed at similar to 345 degrees C, and towards water, at similar to 180 degrees C, which results in high selectivity to hydrogen in the presence of water vapors (minor humidity effect). In contrast, on doping with Pd the response to hydrogen in dry air and to water occurred in the same temperature region (ca. 140 degrees C) leading to low selectivity with a high effect of humidity. An increase in water concentration in the gas phase changes the hydrogen interaction mechanism of Pd doped materials, while that of blank SnO2 is unchanged. The interaction of hydrogen with the catalyst doped SnO2 occurs predominantly through hydroxyl groups when the volumetric concentration of water in the gas phase is higher than that of H-2 by a factor of 1000.

Continuous variation in the pattern of marine v. freshwater foraging in brown trout Salmo trutta L. from Loch Lomond, Scotland

Carbon stable-isotope analysis showed that individual brown trout Salmo trutta in Loch Lomond adopted strategies intermediate to that of freshwater residency or anadromy, suggesting either repeated movement between freshwater and marine environments, or estuarine residency. Carbon stable-isotope (delta C-13) values from Loch Lomond brown trout muscle tissue ranged from those indicative of assimilation of purely freshwater-derived carbon to those reflecting significant utilization of marine-derived carbon. A single isotope, two-source mixing model indicated that, on average, marine C made a 33% contribution to the muscle tissue C of Loch Lomond brown trout. Nitrogen stable isotope, delta N-15, but not delta C-13 was correlated with fork length suggesting that larger fish were feeding at a higher trophic level but that marine feeding was not indicated by larger body size. These results are discussed with reference to migration patterns in other species. (c) 2008 The Authors Journal compilation (c) 2008 The Fisheries Society of the British Isles.

Dissonances in self-reported health and mortality across denominational groups in Northern Ireland

Measures of self-reported health status are increasingly used in research and health policy. However, the inherent subjectivity of the responses gives rise to lingering concerns about their utility, especially across national and cultural boundaries. In this study we use religious denomination as a proxy for Scottish ancestry within Northern Ireland and demonstrate significant differences in levels of self-reported ill-health that are not fully reflected in mortality risks. These findings mirror the differences between Scotland and Northern Ireland previously shown in ecological studies and provide more definitive evidence that even within the United Kingdom factors other than morbidity levels influence the perception and reporting of health status. Possible explanations for the dissonance between morbidity and mortality levels are discussed and the reasons for a preference for socio-economic rather than cultural factors are described. (C) 2010 Elsevier Ltd. All rights reserved.

Hanging Flower Baskets, Blowing in the Wind? Third Sector Groups, Cross-Border Partnerships and the EU Peace Programmes in Ireland

The EU’s Peace programmes in Ireland have promoted the cross-border activity of Third sector groups. Potentially, such activity gives substantive meaning to regional cross-border governance and helps to ameliorate ethno-national conflict by providing positive sum outcomes for ‘post-conflict’ communities. The paper mobilizes focused research conducted by the authors to explore this potential. It finds that while regional cross-border governance has indeed developed under the Peace programmes, the sustainability of the social partnerships underpinning this governance is uncertain and its significance for conflict resolution is qualified by difficulties in forming a stable power-sharing arrangement at the political elite level.

Alternative reproductive tactics in male Cape ground squirrels Xerus inauris

In some animal societies, males vary in the strategies and tactics that they use for reproduction. Explanations for the evolution of alternative tactics have usually focussed on extrinsic factors such as social status, the environment or population density and have rarely examined proximate differences between individuals. Anecdotal evidence suggests that two alternative reproductive tactics occur in cooperatively breeding male Cape ground squirrels. Here we show that there is strong empirical support for physiological and behavioural differences to uphold this claim. `Dispersed' males have higher resting metabolic rates and a heightened pituitary activity, compared with philopatric 'natal' males that have higher circulating cortisol levels. Dispersed males also spend more time moving and less time feeding than natal males. Additionally, lone males spend a greater proportion of their time vigilant and less of their time foraging than those that were in groups. The choice of whether to stay natal or become a disperser may depend on a number of factors such as age, natal group kin structure and reproductive suppression, and the likelihood of successful reproduction whilst remaining natal. Measuring proximate factors, such as behavioural and endocrine function, may provide valuable insights into mechanisms that underlie the evolution of alternative reproductive tactics.

Jellyfish aggregations and leatherback turtle foraging patterns in a temperate coastal environment

Leatherback turtles (Dermochelys coriacea) are obligate predators of gelatinous zooplankton. However, the spatial relationship between predator and prey remains poorly understood beyond sporadic and localized reports. To examine how jellyfish (Phylum Cnidaria: Orders Semaeostomeae and Rhizostomeae) might drive the broad-scale distribution of this wide ranging species, we employed aerial surveys to map jellyfish throughout a temperate coastal shelf area bordering the northeast Atlantic. Previously unknown, consistent aggregations of Rhizostoma octopus extending over tens of square kilometers were identified in distinct coastal

Sea turtle diving and foraging behaviour around the Greek Island of Kefalonia

The discovery of a shallow water (

Trusting Groups in Coalition Formation using Social Distance

In environments where distributed team formation is key, and defections are possible, the use of trust as social capital allows social norms to be defied and compared. An agent can use this information, when invited to join a group or collation, to decide whether or not its utility will be increased by joining. In this work a social network approach is used to define and reason about the relationships contained in the agent community. Previous baseline work is extended with two decision making mechanisms. These are compared by simulating an abstract grid-like environment, and preliminary results are reported.

Contextualism as an important facet of individualism-collectivism: personhood beliefs across 37 national groups

Beliefs about personhood are understood to be a defining feature of individualism-collectivism (I-C), but they have been insufficiently explored, given the emphasis of research on values and self-construals. We propose the construct of contextualism, referring to beliefs about the importance of context in understanding people, as a facet of cultural collectivism. A brief measure was developed and refined across 19 nations (Study 1: N = 5,241), showing good psychometric properties for cross-cultural use and correlating well at the nation level with other supposed facets and indicators of I-C. In Study 2 (N = 7,623), nation-level contextualism predicted ingroup favoritism, corruption and differential trust of ingroup and outgroup members, while controlling for other facets of I-C, across 34 nations. We conclude that contextualism is an important part of cultural collectivism. This highlights the importance of beliefs alongside values and self-representations, and contributes to a wider understanding of cultural processes.

Second-order NMR spectra at high field of common organic functional groups

The proton NMR spectra of aryl n-propyl sulfides gave rise to what may appear to be first-order proton NMR spectra. Upon oxidation to the corresponding sulfone, the spectra changed appearance dramatically and were clearly second-order. A detailed analysis of these second-order spectra, in the sulfone series, provided vicinal coupling constants which indicated that these compounds had a moderate preference for the anti-conformer, reflecting the much greater size of the sulfone over the sulfide. It also emerged, from this study, that the criterion for observing large second-order effects in the proton NMR spectra of 1,2-disubstituted ethanes was that the difference in vicinal coupling constants must be large and the difference in geminal coupling constants must be small. n-Propyl triphenylphosphonium bromide and 2-trimethylsilylethanesulfonyl chloride, and derivatives thereof, also exhibited second-order spectra, again due to the bulky substituents. Since these spectra are second-order due to magnetic nonequivalence of the nuclei in question, not chemical shifts, the proton spectra are perpetually second-order and can never be rendered first-order by using higher field NMR spectrometers.