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221.
Employee creativity is critical for an organization's innovativeness and survival in today's competitive business environment. As such, scholars have devoted significant attention to the predictors of employee creativity, seeking to understand how to best increase employees' creative output. However, employee creativity may not always translate into organizational innovation and performance. In fact, employee creativity may result in various outcomes for creative individuals, their coworkers, teams, and organizations. While there have been several integrative reviews on the antecedents of creativity, an in-depth review of the outcomes of creativity is still needed to gain a holistic understanding of the benefits and costs of employee creativity and identify fruitful areas for future research. Thus, we aim to provide a comprehensive multilevel examination of the theories, methods, and creativity-related constructs used to examine the outcomes of creativity. We also provide several theoretical and empirical opportunities for future research. This review may provide managers with knowledge of the pros and cons of employee creativity, enabling them to make informed decisions on how to better manage employee creativity. 相似文献
222.
This paper explores the conceptualisation and application of 'protection' by the United Nations High Commissioner (UNHCR), Ugandan government, and Congolese refugees in Kyaka II refugee settlement, Uganda. Analysing the origins and consequences of a demonstration against school fees, and drawing on other ethnographic data, it explores how different interpretations of this incident reflect different conceptions of, and approaches to, protection. Ugandan government officials viewed the demonstration as a security incident; Congolese and Ugandan adults responded with increased monitoring and 'sheltering' of children and young people; students justified the demonstration as a legitimate manifestation of their rights; while UNHCR promoted assistance and resettlement. The paper argues that prevailing protection responses, including 'sensitisation', sheltering, and resettlement, are de-contextualised from daily realities and fail to address the underlying power relations that undermine protection. It concludes with recommendations on how international refugee agencies can reorient assistance to address protection concerns in refugee contexts. 相似文献
223.
Christina M. Cianfrani W. Cully Hession Donna M. Rizzo 《Journal of the American Water Resources Association》2006,42(4):941-956
ABSTRACT: Forty‐six independent stream reaches in southeastern Pennsylvania were surveyed to assess the relationships between geomorphic and habitat variables and watershed total impervious area (TIA) and to test the ability of the impervious cover model (ICM) to predict the impervious category based on stream reach variables. Ten variables were analyzed using simple and multivariate statistical techniques including scatter‐plots, Spearman's Rank correlations, principal components analysis (PCA), and discriminant analysis (DA). Graphical analysis suggested differences in the response to TIA between the stream reaches with less than 13 percent TIA and those with greater than 24 percent TIA. Spearman's Rank correlations showed significant relationships for large woody debris and sinuosity when analyzing the entire dataset and for depth diversity and the standard deviation of maximum pool depths when analyzing stream reaches with greater than 24 percent TIA. Classification into the ICM using DA was 49 percent accurate; however, the stream reaches did support the ICM in other ways. These results indicate that stream reach response to urbanization may not be consistent across geographical regions and that local conditions (specifically riparian buffer vegetation) may significantly affect channel response; and the ICM, used in the appropriate context, can aid in the management of stream reaches and watersheds. 相似文献
224.
Christina Tague Christi McMichael Allen Hope Janet Choate Robyn Clark 《Journal of the American Water Resources Association》2004,40(3):575-589
ABSTRACT: Distributed hydrologic models which link seasonal streamflow and soil moisture patterns with spatial patterns of vegetation are important tools for understanding the sensitivity of Mediterranean type ecosystems to future climate and land use change. RHESSys (Regional Hydro‐Ecologic Simulation System) is a coupled spatially distributed hydroecological model that is designed to be able to represent these feedbacks between hydrologic and vegetation carbon and nutrient cycling processes. However, RHESSys has not previously been applied to semiarid shrubland watersheds. In this study, the hydrologic submodel of RHESSys is evaluated by comparing model predictions of monthly and annual streamflow to stream gage data and by comparing RHESSys behavior to that of another hydrologic model of similar complexity, MIKESHE, for a 34 km2 watershed near Santa Barbara, California. In model intercomparison, the differences in predictions of temporal patterns in streamflow, sensitivity of model predictions to calibration parameters and landscape representation, and differences in model estimates of soil moisture patterns are explored. Results from this study show that both models adequately predict seasonal patterns of streamflow response relative to observed data, but differ significantly in terms of estimates of soil moisture patterns and sensitivity of those patterns to the scale of landscape tessellation used to derive spatially distributed elements. This sensitivity has implications for implementing RHESSys as a tool to investigate interactions between hydrology and ecosystem processes. 相似文献
225.
Successful invaders often become established in new ranges by outcompeting native species. The “evolution of increased competitive ability” hypothesis predicts that invasive species are subjected to less predation and parasitization than sympatric native species, and thus can allocate resources from defence and immunity to growth and fecundity, thereby achieving higher fitness. In this study, we examined whether American invasive Polistes dominula paper wasps have reduced immunocompetence. To explore this scenario, we tested their susceptibility towards parasites and pathogens at both the individual (immune defence) and colony levels, i.e. hygienic behaviour (removal of diseased individuals by nestmates). First, we examined the response to the specific coevolved parasite Xenos vesparum (lost after invasion) in terms of individual host susceptibility and hygienic behaviour. Second, we explored the response against general pathogens by quantifying the bacterial clearance in individual wasps after a challenge with Escherichia coli and hygienic behaviour after a challenge with the fungus Beauveria bassiana. Our results show that American invasive P. dominula have a higher response against X. vesparum at the colony level, but at the individual level their susceptibility is not significantly different from conspecifics of the native range. On the other hand, invasive P. dominula display lower response after a challenge with general pathogens at both the individual and colony levels. While supporting the hypothesis of a reduction of immunocompetence towards general pathogens in invasive species, these findings also suggest that the response against coevolved parasites might follow different evolutionary pathways which are not always easily predictable. 相似文献
226.
Christina Chroni Adamantini Kyriacou Irene Georgaki Thrassyvoulos Manios Maria Kotsou Katia Lasaridi 《Waste management (New York, N.Y.)》2009,29(5):1520-1525
Windrow composting of source-separated biowaste was studied in a pilot plant in Crete, with regard to abiotic factors, gas concentration in the pile and succession of functional microbial groups. The pH, C/N ratio and VS content, as well as the O2 and CO2 concentration, correlated well with composting time, indicating typical composting behaviour. Most of the microbial groups examined exhibited their highest counts towards the end of the thermophilic phase, with declining trends thereafter. The population of total mesophilic and thermophilic bacteria increased during the mild thermophilic phase and followed the temperature decline thereafter. Results on these microbial groups and fungi indicate that the timing of the thermophilic stage in the composting process, in addition to the peak temperature and duration of the stage, affects the microbial succession. Escherichia coli were detected for over 2 months of processing, in spite of the high temperatures achieved; only after about 3 months of composting did its population decline below the detection limit. 相似文献
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229.
Teresa L. Dzieweczynski Christina E. Perazio 《Behavioral ecology and sociobiology》2012,66(9):1277-1284
The presence of an audience alters male–male interactions in a number of social species. Additionally, whether individuals have interacted previously may influence the current encounter. Although it is clear that previous exposure influences communication and that the presence of an audience affects behavior in a number of contexts, how these phenomena might interact to impact interactions is underexplored. This study examined the effects of audience familiarity on male–male interactions in Siamese fighting fish (Betta splendens). Treatments that varied based on familiarity with and sex of the audience as well as length of time after initial audience exposure were used to investigate whether male aggressive interactions were affected by these factors. Males first encountered an individual that would later become an audience. Pairs of males then interacted with each other in either the presence of this familiar individual or a new, unfamiliar audience conspecific or with no audience at all. Opponent-directed gill flaring and tail beats were influenced by familiarity with the audience individual, although they were affected differently by the sex of the audience present. Gill flaring was affected predominantly by the presence of a male audience, whereas tail beat rate was influenced by the presence of a female audience. Gill flaring rate did not differ regardless of whether 4 or 24?h had passed between the initial exposure to the audience and the testing phase. In contrast, the familiarity effect disappeared after 4?h for tail beats. These results stress the importance of considering the familiarity of individuals within a network when examining communication networks. 相似文献
230.
Measuring diversity: the importance of species similarity 总被引:4,自引:0,他引:4
Realistic measures of biodiversity should reflect not only the relative abundances of species, but also the differences between them. We present a natural family of diversity measures taking both factors into account. This is not just another addition to the already long list of diversity indices. Instead, a single formula subsumes many of the most popular indices, including Shannon's, Simpson's, species richness, and Rao's quadratic entropy. These popular indices can then be used and understood in a unified way, and the relationships between them are made plain. The new measures are, moreover, effective numbers, so that percentage changes and ratio comparisons of diversity value are meaningful. We advocate the use of diversity profiles, which provide a faithful graphical representation of the shape of a community; they show how the perceived diversity changes as the emphasis shifts from rare to common species. Communities can usefully be compared by comparing their diversity profiles. We show by example that this is a far more subtle method than any relying on a single statistic. Some ecologists view diversity indices with suspicion, questioning whether they are biologically meaningful. By dropping the naive assumption that distinct species have nothing in common, working with effective numbers, and using diversity profiles, we arrive at a system of diversity measurement that should lay much of this suspicion to rest. 相似文献