With changing retirement ages and an aging workforce, interest is growing on the potential contribution of relevant bundles of HR practices in eliciting well-being and performance among aging workers. Drawing on theories on lifespan development and self-regulation, we distinguished two bundles of HR practices: development HR practices that help individual workers reach higher levels of functioning (e.g. training), and maintenance HR practices that help individual workers maintain their current levels of functioning in the face of new challenges (e.g. performance appraisal). Further, based on lifespan theories, we expected and found that the association between development HR practices and well-being (i.e. job satisfaction, organisational commitment and organisational fairness) weakens, and that the associations between maintenance HR practices and well-being, and between development HR practices and employee performance, strengthen with age. In addition, a third bundle of 'job enrichment' HR practices emerged that elicited higher job performance among aging workers.

The banding procedure produced fewer acute effects, but a greater suppression of growth than surgical castration and induced prolonged wound formation in the older age group, suggesting that this procedure may not be as suitable for yearling cattle.

Job embeddedness is a relatively new concept that offers the potential to improve our ability to explain why people stay in their jobs.This article outlines the development and testing of new measures of on-and off-the-job embeddedness.Analyses of survey data show the measures demonstrate adequate psychometric properties across samples (three military and one nonmilitary organization) and across different organizational levels, genders, and tenure, as well as discriminant validity over other turnover-relevant constructs and appropriate convergent validity with a number of further constructs identified in the literature.

The addition of small amounts of special purpose hardware to conventional machines increases the efficiency of Lisp systems with dynamic type checks. In a similar way, this paper proposes additional hardware to dynamically check the correctness of parallel execution of Lisp programs.The key idea is the use of fully associative caches as a means of maintaining and enforcing a set of dependencies between portions of the program.

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Methane (CH4) emissions from a herd of 58 grazing cattle were determined in a field experiment using paddock-scale (micrometeorological) methods. The emissions were also measured daily from each animal, using the sulfur hexafluoride tracer method. The paddock-scale methods exploit how the gas, once emitted from the cattle, is transported and dispersed by the wind. Hence, the emission rate may be calculated from measurements of windspeed, wind direction and turbulence statistics, as well as CH4 concentration upwind and downwind of the herd. The paddock-scale methods include a mass-budget approach, flux-gradient method and gas dispersion model. Accuracy can be assessed in unprecedented detail because the animal-scale (reference) method included all individuals in the herd, and the measurement site was ideal for micrometeorological methods (flat, usually windy and free of obstructions that alter the turbulent airflow). The cattle were hand-reared steers of average weight 325 ± 20 kg. Based on the animal-scale method, the average CH4 emission rate over 9 days was 161 ± 20 g/steer.day. The gas dispersion model, when utilising vertical concentration profiles, yielded on average 27% greater emissions. The other paddock-scale methods agreed with the animal-scale method, provided the cattle were at least 22 m away from the location of the downwind concentration measurements. When the cattle were allowed to graze as closely as 5 m from the instruments, the paddock-scale methods gave greater emissions than the animal-scale method; reasons for this are discussed.

Recent interest in making and materiality spans from the humanities and social sciences to engineering, science, and design. Here, we consider making through the lens of a unique computational theory of design: shape grammars. We propose a computational theory of making based on the improvisational, perception and action approach of shape grammars and the shape algebras that support them. We modify algebras for the materials (basic elements) of shapes to define algebras for the materials of objects, or things. Then we adapt shape grammars for computing shapes to making grammars for computing things. We give examples of making grammars and their algebras. We conclude by reframing designing and making in light of our computational theory of making.Keywords: computational model(s); design theory; perception; reflective practice; shape grammarThe recent wave of interest in making, materiality, and material culture -the so-called "material turn" and "new materialism" (Coole & Frost, 2010;Dolphijn & van der Tuin, 2012) -in the social sciences and humanities has been paralleled by growing attention and research on new materials, making, and manufacturing processes in engineering, science, and design. While humanists and social scientists inquire into the subjective, embodied, situated relationships between people and material things, their engineer, scientist, and designer colleagues tend to focus on technological innovations and applications of advanced materials and fabrication devices.We pursue a different tack in the terrain of making and material things. We consider making from a computational point of view. Our computational view intersects with some concerns above, but offers a distinct alternative to how we can think about and engage in making. Our view is rooted in computationbut computation beyond the narrow, digital kind of computation to a more general and perceptual kind in which people carry out operations with things that may only have digital approximations. In a similar vein, we consider making to be processes carried out by people to form material things. From this perspective, the kinds of making are extensive and diverse -ranging from drawing a picture on paper, to producing an image on a computer screen, to weaving a basket, to 3D printing a model, to machining engine parts, to constructing a building. 2In developing our computational approach to making, we also consider the relationship between making and designing, the latter often understood as an intellectual or cognitive activity resulting in a plan for action or making. Our approach collapses many of the dualisms associated with designing and making that originate with Aristotle's concept of hylomorphism. Hylomorphism regards creation as the imposition of an idea of form (morphe) upon passive material or matter (hyle). A reincarnation of hylomorphism, perhaps better known to architects, is Alberti's distinction between designing -as a "pre-ordering of the lines and angles conceived in the mind" (Alberti, 1986: p 2) -and building. Th...

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