Identifying and understanding factors influencing the uptake of new technologies on dairy farms in SW England using the theory of reasoned action

Whilst much is known of new technology adopters, little research has addressed the role of their attitudes in adoption decisions; particularly, for technologies with evident economic potential that have not been taken up by farmers. This paper presents recent research that has used a new approach which examines the role that adopters' attitudes play in identifying the drivers of and barriers to adoption. The study was concerned with technologies for livestock farming systems in SW England, specifically oestrus detection, nitrogen supply management, and, inclusion of white clover. The adoption behaviour is analysed using the social-psychology theory of reasoned action to identify factors that affect the adoption of technologies, which are confirmed using principal components analysis. The results presented here relate to the specific adoption behaviour regarding the Milk Development Council's recommended observation times for heat detection. The factors that affect the adoption of this technology are: cost effectiveness, improved detection and conception rates as the main drivers, whilst the threat to demean the personal knowledge and skills of a farmer in 'knowing' their cows is a barrier. This research shows clearly that promotion of a technology and transfer of knowledge for a farming system need to take account of the beliefs and attitudes of potential adopters. (C) 2006 Elsevier Ltd. All rights reserved.

Features of the Atlantic diet and its healthiness: Theory and evidence from social science

In order to understand diets, why and how they change and can be influenced, it is important to understand how food choices are made. The has been the subject of, considerable study within many of the social science disciplines and the humanities. The paper draws on the theoretical and empirical work of psychologists, sociologists, economists, market researchers, anthropologists, geographers and historians to understand better the forces behind food choice, derive some general empirical messages from the literature, to shed light on food choice in a European context and to address the question of whether there is, or has been, a recognisably Atlantic diet. The paper proceeds to analyse the characteristics of the food consumption patterns in the Atlantic diet countries, examines whether their food consumption patterns are homogenous (i.e. similar across the countries of this group), whether they are specific (i.e. different from the ones in other country groups) and finally evaluates the nutritional composition of the Atlantic diet against the WHO/FAO recommendations for a healthy and wholesome diet.

Managing threatened species: the ecological toolbox, evolutionary theory and declining-population paradigm

1. The management of threatened species is an important practical way in which conservationists can intervene in the extinction process and reduce the loss of biodiversity. Understanding the causes of population declines (past, present and future) is pivotal to designing effective practical management. This is the declining-population paradigm identified by Caughley. 2. There are three broad classes of ecological tool used by conservationists to guide management decisions for threatened species: statistical models of habitat use, demographic models and behaviour-based models. Each of these is described here, illustrated with a case study and evaluated critically in terms of its practical application. 3. These tools are fundamentally different. Statistical models of habitat use and demographic models both use descriptions of patterns in abundance and demography, in relation to a range of factors, to inform management decisions. In contrast, behaviour-based models describe the evolutionary processes underlying these patterns, and derive such patterns from the strategies employed by individuals when competing for resources under a specific set of environmental conditions. 4. Statistical models of habitat use and demographic models have been used successfully to make management recommendations for declining populations. To do this, assumptions are made about population growth or vital rates that will apply when environmental conditions are restored, based on either past data collected under favourable environmental conditions or estimates of these parameters when the agent of decline is removed. As a result, they can only be used to make reliable quantitative predictions about future environments when a comparable environment has been experienced by the population of interest in the past. 5. Many future changes in the environment driven by management will not have been experienced by a population in the past. Under these circumstances, vital rates and their relationship with population density will change in the future in a way that is not predictable from past patterns. Reliable quantitative predictions about population-level responses then need to be based on an explicit consideration of the evolutionary processes operating at the individual level. 6. Synthesis and applications. It is argued that evolutionary theory underpins Caughley's declining-population paradigm, and that it needs to become much more widely used within mainstream conservation biology. This will help conservationists examine critically the reliability of the tools they have traditionally used to aid management decision-making. It will also give them access to alternative tools, particularly when predictions are required for changes in the environment that have not been experienced by a population in the past.

Rate-limiting steps in the development of atherosclerosis: the response-to-influx theory

A large number of processes are involved in the pathogenesis of atherosclerosis but it is unclear which of them play a rate-limiting role. One way of resolving this problem is to investigate the highly non-uniform distribution of disease within the arterial system; critical steps in lesion development should be revealed by identifying arterial properties that differ between susceptible and protected sites. Although the localisation of atherosclerotic lesions has been investigated intensively over much of the 20th century, this review argues that the factor determining the distribution of human disease has only recently been identified. Recognition that the distribution changes with age has, for the first time, allowed it to be explained by variation in transport properties of the arterial wall; hitherto, this view could only be applied to experimental atherosclerosis in animals. The newly discovered transport variations which appear to play a critical role in the development of adult disease have underlying mechanisms that differ from those elucidated for the transport variations relevant to experimental atherosclerosis: they depend on endogenous NO synthesis and on blood flow. Manipulation of transport properties might have therapeutic potential. Copyright (C) 2004 S. Karger AG, Basel.

Some theory for constructing minimum aberration fractional factorial designs

Minimum aberration is the most established criterion for selecting a regular fractional factorial design of maximum resolution. Minimum aberration designs for n runs and n/2 less than or equal to m < n factors have previously been constructed using the novel idea of complementary designs. In this paper, an alternative method of construction is developed by relating the wordlength pattern of designs to the so-called 'confounding between experimental runs'. This allows minimum aberration designs to be constructed for n runs and 5n/16 less than or equal to m less than or equal to n/2 factors as well as for n/2 less than or equal to m < n.

Population subdivision and molecular sequence variation: Theory and analysis of Drosophila ananassae data

Population subdivision complicates analysis of molecular variation. Even if neutrality is assumed, three evolutionary forces need to be considered: migration, mutation, and drift. Simplification can be achieved by assuming that the process of migration among and drift within subpopulations is occurring fast compared to Mutation and drift in the entire population. This allows a two-step approach in the analysis: (i) analysis of population subdivision and (ii) analysis of molecular variation in the migrant pool. We model population subdivision using an infinite island model, where we allow the migration/drift parameter Theta to vary among populations. Thus, central and peripheral populations can be differentiated. For inference of Theta, we use a coalescence approach, implemented via a Markov chain Monte Carlo (MCMC) integration method that allows estimation of allele frequencies in the migrant pool. The second step of this approach (analysis of molecular variation in the migrant pool) uses the estimated allele frequencies in the migrant pool for the study of molecular variation. We apply this method to a Drosophila ananassae sequence data set. We find little indication of isolation by distance, but large differences in the migration parameter among populations. The population as a whole seems to be expanding. A population from Bogor (Java, Indonesia) shows the highest variation and seems closest to the species center.

A case of four-coordinate silver(I) adopting a high energy planar geometry. Experiment and theory

The ligands PhL and MeL are obtained by condensing 2-formylpyridine with benzil dihydrazone and diacetyl dihydrazone, respectively, in 2: 1 molar proportion. With silver( I), PhL yields a double-stranded dinuclear cationic helicate 1 in which the metal is tetrahedral but MeL gives a cationic one-dimensional polymeric complex 2 where silver( I) is distorted square planar and the ligand backbone is nearly planar. In both complexes, metal: ligand ratio is 1: 1. Ab initio calculations on the ligands at the HF/6-31+G* level reveal that while PhL strongly prefers a helical conformation, MeL has a natural inclination to remain in a planar conformation. Density functional theory calculations on model silver( I) complexes show that formation of the linear polymer in the case of MeL is also an important factor in imposing the planar geometry of Ag(I) in 2.

A perspective on chaos theory: Potential applications to intelligent buildings

Mathematical models have been vitally important in the development of technologies in building engineering. A literature review identifies that linear models are the most widely used building simulation models. The advent of intelligent buildings has added new challenges in the application of the existing models as an intelligent building requires learning and self-adjusting capabilities based on environmental and occupants' factors. It is therefore argued that the linearity is an impropriate basis for any model of either complex building systems or occupant behaviours for control or whatever purpose. Chaos and complexity theory reflects nonlinear dynamic properties of the intelligent systems excised by occupants and environment and has been used widely in modelling various engineering, natural and social systems. It is proposed that chaos and complexity theory be applied to study intelligent buildings. This paper gives a brief description of chaos and complexity theory and presents its current positioning, recent developments in building engineering research and future potential applications to intelligent building studies, which provides a bridge between chaos and complexity theory and intelligent building research.

Theory and practice in value management: a reply to Ellis et al (2005)

The constructivist model of 'soft' value management (VM) is contrasted with the VM discourse appropriated by cost consultants who operate from within UK quantity surveying (QS) practices. The enactment of VM by cost consultants is shaped by the institutional context within which they operate and is not necessarily representative of VM practice per se. Opportunities to perform VM during the formative stages of design are further constrained by the positivistic rhetoric that such practitioners use to conceptualize and promote their services. The complex interplay between VM theory and practice is highlighted and analysed from a non-deterministic perspective. Codified models of 'best practice' are seen to be socially constructed and legitimized through human interaction in the context of interorganizational networks. Published methodologies are seen to inform practice in only a loose and indirect manner, with extensive scope for localized improvization. New insights into the relationship between VM theory and practice are derived from the dramaturgical metaphor. The social reality of VM is seen to be constituted through scripts and performances, both of which are continuously contested across organizational arenas. It is concluded that VM defies universal definition and is conceptualized and enacted differently across different localized contexts.