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251.
The focus of this paper is cognitive convergence in a globally distributed team (GDT), defined as the process by which cognitive structures of distributed team members gradually become more similar over time. To explore the convergence process, we employed a longitudinal, ethnographic research strategy that allowed us to follow a naturally occurring GDT over a 14‐month period, producing a rich case study portraying factors and processes that influence convergence. Confirming previous studies, we find that increases in shared cognition alone are not sufficient to account for performance gains on a GDT. Rather, it may be necessary not only to increase the sharing of cognition, but also to reverse a pattern of increasing divergence that can result from rejection of key knowledge domains. We also found that several factors influence the process of cognitive convergence beyond direct knowledge sharing. These include: separate but parallel or similar learning experiences in a common context; the surfacing of hidden knowledge at remote sites by third‐party mediators or knowledge brokers; and shifts in agent self‐interest that motivate collaboration and trigger the negotiation of task interdependence. Also relevant to cognitive convergence on a GDT is the geographical distribution pattern of people and resources on the ground, and the different ways in which leaders exploit the historical, cultural and linguistic dimensions of such distribution to further their own political agendas. Several propositions related to these observations are suggested. We conclude that GDTs can be effective in bringing together divergent points of view to yield new organizational capabilities, but such benefits require that leaders and members recognize early and explicitly the existence and validity of their differences. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
252.
253.
Workers and fence-line communities have been the first to benefit from the substantial reductions in toxic chemical use and byproducts in industrial production resulting from the Massachusetts Toxics Use Reduction Act (TURA). As TURA motivates reformulation of products as well as retooling of production processes, benefits could extend more broadly to large-scale reductions in everyday exposures for the general population. Household exposure studies, including those conducted by Silent Spring Institute, show that people are exposed to complex mixtures of indoor toxics from building materials and a myriad of consumer products. Pollutants in homes are likely to have multiple health effects because many are classified as endocrine disrupting compounds (EDCs), with the ability to interfere with the body’s hormone system. Product-related EDCs measured in homes include phthalates, halogenated flame retardants, and alkylphenols. Silent Spring Institute’s chemical analysis of personal care and cleaning products confirms many are potential sources of EDCs, highlighting the need for a more comprehensive toxics use reduction (TUR) approach to reduce those exposures. Toxics use reduction targeted at EDCs in consumer products has the potential to substantially reduce occupational and residential exposures. The lessons that have emerged from household exposure research can inform improved chemicals management policies at the state and national levels, leading to safer products and widespread health and environmental benefits. 相似文献
254.
Homing pigeons are well known as good homers, and the knowledge of principal parameters determining their homing behaviour
and the neurological basis for this have been elucidated in the last decades. Several orientation mechanisms and parameters—sun
compass, earth’s magnetic field, olfactory cues, visual cues—are known to be involved in homing behaviour, whereas there are
still controversial discussions about their detailed function and their importance. This paper attempts to review and summarise
the present knowledge about pigeon homing by describing the known orientation mechanisms and factors, including their pros
and cons. Additionally, behavioural features like motivation, experience, and track preferences are discussed. All behaviour
has its origin in the brain and the neuronal basis of homing and the neuroanatomical particularities of homing pigeons are
a main topic of this review. Homing pigeons have larger brains in comparison to other non-homing pigeon breeds and particularly
show increased size of the hippocampus. This underlines our hypothesis that there is a relationship between hippocampus size
and spatial ability. The role of the hippocampus in homing and its plasticity in response to navigational experience are discussed
in support of this hypothesis. 相似文献
255.
The sustainability performance of five potential UK biodiesel feedstocks is reviewed and their greenhouse gas performance investigated using the carbon and sustainability reporting methods of the UK Renewable Transport Fuel Obligation (RTFO). Of the feedstocks examined, and for which the RTFO supplies default carbon intensity values, only used cooking oil has guaranteed sustainability benefits. The other feedstocks have CO2e payback periods of 25–5503 years if grown on converted forest or grassland, yet the RTFO currently requires no guarantee that this conversion has not taken place and requires no avoidance of indirect effects. As currently designed, the RTFO risks substantial, adverse environmental effects. 相似文献
256.
Julia Ostner Peter Kappeler Michael Heistermann 《Behavioral ecology and sociobiology》2008,62(4):627-638
Intense reproductive competition and social instability are assumed to increase concentrations of glucocorticoids and androgens
in vertebrates, as a means of coping with these challenges. In seasonally breeding redfronted lemurs (Eulemur fulvus rufus), the mating and the birth season and the associated increased male competition are predicted to pose such reproductive challenges.
In this paper, we investigate seasonal variation in hormone excretion in male redfronted lemurs, and examine whether this
variation is associated with social or ecological factors. Although dominance status has been shown to affect individual stress
levels across many taxa, we predicted no rank-related differences in glucocorticoids for redfronted lemurs because relatively
equal costs are associated with both high and low rank positions (based on patterns of rank acquisition/maintenance and threats
toward subordinates). Over a 14-month period, we collected behavioral data (1843 focal hours) and 617 fecal samples from 13
redfronted lemur males in Kirindy Forest/Madagascar. We found no general rank-related pattern of testosterone or glucocorticoid
excretion in this species. Both hormones were excreted at significantly higher levels during the mating and the birth season,
despite social stability during both periods. The elevated mating season levels may be explained by increased within-group
reproductive competition during this time and are in line with previous studies of other seasonally reproducing primates.
For the birth season increase, we propose that the predictable risk of infanticide in this highly seasonal species affects
male gonadal and adrenal endocrine activity. We evaluate alternative social and ecological factors influencing the production
of both hormone classes and conclude based on our preliminary investigations that none of them can account for the observed
pattern. 相似文献
257.
258.
At the centre of the debate surrounding sustainable development is a recognition that companies can make a major contribution by being environmentally and socially responsible and that tools associated with these concepts can enhance the competitiveness and economic performance of the firm. In this paper we go further in arguing that in a world of globalisation it is equally important to look at issues of international trade. In an examination of free trade we argue that it is neither fully consistent with sustainable development nor to the benefit of business. We point to a new imperative to develop sound sourcing, and equitable and fair trading relationships. We identify issues associated with fair trade (including issues of human rights, fair wages, sustainability reporting procedures and codes of conduct on ethics) and associated tools of analysis (guaranteed prices, codes of conduct and end price audits). The paper argues that in a world of globalisation with greater transparency and information availability it will be important for companies to be clear about their policies on supply chain management and trade. Indeed, with the growth of an active and sophisticated civil society, it will be argued that policies associated with sound sourcing, equitable trade and fair trade could provide companies with a new competitive strategy based on ethical standards communicated to the consumer through a strategy of differentiation. We explore strategies for the integration of fair trade policies, strategies and standards, and the opportunities for new markets and niches that this presents. It is argued that the integration of fair trade into a business strategy can enhance competitiveness. 相似文献
259.
This paper examines the problem of measuring sustainable governance in the European Union (EU-27) through the use of duality and the Slutsky equation. The proposed methodology is based on the application of a three-dimensional optimisation model, where the arguments of the objective (sustainable social welfare) function are economic goods that contribute to sustainable economic growth; environmental goods that provide for sustainable environmental protection; and social goods through which sustainable social development is achieved. The dual problem, formulated through this three-dimensional theoretical model, is solved to find the optimal solution, indicating a certain sustainability level. We suggest that this solution can be used for calculating the value of what we define here as the sustainable governmental policy indicator, which is considered to provide quantitative measurement of government policies on sustainable development within the context of ‘good governance’. Furthermore, it is suggested that the Slutsky equation can be used as a reliable method for long-term monitoring and planning of national as well as international good governance with regard to sustainable development policies. In its empirical part, the paper applies the theoretical model in an analysis of the sustainable development indicators (as set out in the Sustainable Development Strategy (SDS) of the EU) in Bulgaria for the period 2000–2010 and compares them to those of the EU-27. 相似文献
260.
Seventeen immature green turtles Chelonia mydas were tracked concurrently by automated ultrasonic receivers at a coral reef off North-Eastern Australia (September–December 2010, 16.4°S, 145.6°E). The majority (n = 11) were tracked for the entire 100-day study, the remainder for 23–85 days. Detection data aggregated at 30-min intervals produced median 6.5–35 daily locations for individual turtles. Home range areas (95 % utilisation distribution) were ≤1 km2, $ {\bar{\text{x}}} $ ± SD = 0.74 km2 ± 0.159. To the best of our knowledge, these are the first home range estimates for C. mydas foraging at offshore tropical reefs. The findings are important for conservation in revealing near-continuous presence of the same individuals within a small geographic area. Time between detections was very short (median <3 min) demonstrating passive ultrasonic technology can track multiple turtles in a foraging environment with higher temporal resolution than typically achieved by satellite tracking. 相似文献