Home About us Contact
|
Home About us Contact | ||
|
|
||
Appropriate Context (appropriate + context)
Selected AbstractsFactors affecting nest predation on forest songbirds in North AmericaIBIS, Issue 2007FRANK R. THOMPSON III Nest predation is an important factor in the ecology of passerines and can be a large source of mortality for birds. I provide an overview of factors affecting nest predation of passerines in North America with the goal that it may provide some insight into the ecology and management of woodland birds in the United Kingdom. Although several factors influence productivity, nest success is perhaps the most widely measured demographic characteristic of open-cup-nesting birds, and nest predation is usually the largest cause of nest failure. The identity of predator species, and how their importance varies with habitat and landscape factors, must be known for managers and scientists to design effective conservation plans and place research on nest predation in the appropriate context. Recent studies using video surveillance have made significant contributions to our understanding of the relative importance of different predator taxa in North America. Spatial and temporal variation in nest predation can be better understood when landscapes are placed in a biogeographical context and local habitat and nest-site effects are placed in a landscape context. Low productivity resulting from high nest predation is one of several potential causes of bird population declines in North America and the UK. Although the ,forest fragmentation paradigm' from the eastern US may not apply directly to the UK, thinking about avian demographics from a multiscale perspective, and consideration of factors affecting nest predation with knowledge of the dominant predator species, may provide insight into population declines. [source] Genetic interactions between marine finfish species in European aquaculture and wild conspecificsJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2001Youngson The principal species of marine aquaculture in Europe are Atlantic salmon (Salmo salar), sea bass (Dicentrarchus labrax) and sea bream (Sparus auratus). For Atlantic salmon and sea bass, a substantial part of total genetic variation is partitioned at the geographical population level. In the case of sea bream, gene flow across the Azores/Mediterranean scale appears to be extensive and population structuring is not detected. For Atlantic salmon and sea bass, natural population structure is at risk from genetic interaction with escaped aquaculture conspecifics. The locally adaptive features of populations are at risk from interbreeding with non-local aquaculture fish. Wild populations, generally, are at risk from interactions with aquaculture fish that have been subject to artificial selection or domestication. Atlantic salmon is the main European aquaculture species and its population genetics and ecology have been well-studied. A general case regarding genetic interactions can be based on the information available for salmon and extended to cover other species, in the appropriate context. A generalized flow chart for interactions is presented. Salmon escape from aquaculture at all life stages, and some survive to breed among wild salmon. Reproductive fitness in the escaped fish is lower than in native, wild fish because of behavioural deficiencies at spawning. However, as the number of salmon in aquaculture greatly exceeds the number of wild fish, even small fractional rates of escape may result in the local presence of large numbers, and high frequencies, of escaped fish. At present, policy and legislation in relation to minimizing genetic interactions between wild and aquaculture fish is best developed for Atlantic salmon, through the recommendations of the Oslo Agreement developed by the North Atlantic Salmon Conservation Organization and subsequent agreements on their implementation. In future, the potential use of genetically modified fish in aquaculture will make additional policy development necessary. Improved containment is recommended as the key to minimizing the numbers and therefore the effects of escaped fish. Emergency recovery procedures are recommended as a back-up measure in the case of containment failure. Reproductive sterility is recommended as a future key to eliminating the genetic potential of escaped fish. The maintenance of robust populations of wild fish is recommended as a key to minimizing the effects of escaped fish on wild populations. [source] Professionalism vs Commercialism: The Association Between Non-Audit Services (NAS) and Audit IndependenceJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 5-6 2001Divesh S. Sharma The implications of the provision of NAS to audit clients on audit independence have attracted considerable regulatory and research attention. This study contributes to this topical issue by investigating the association between NAS and audit independence using actual fee data and a more appropriate context that enables a proper ex post assessment of the correctness of the auditor's opinion decision. The results are consistent with the notion that auditors exhibit low propensity to issue a going-concern qualification to clients generating higher proportions of NAS fees to total fees and raise independence implications regarding the joint provision of audit and NAS. [source] A murine model of mixed connective tissue disease induced with U1 small nuclear RNP autoantigenARTHRITIS & RHEUMATISM, Issue 2 2006Eric L. Greidinger Objective To test whether immunizing mice with autoantigens closely linked to mixed connective tissue disease (MCTD) could induce an MCTD-like clinical syndrome distinguishable from systemic lupus erythematosus (SLE). Methods Transgenic and knockout C57BL/6-derived mice were immunized subcutaneously at age 8,12 weeks with U1,70-kd small nuclear RNP (70K) fusion protein along with either Freund's complete adjuvant (CFA) or U1 RNA. After 2 months, mice were killed and analyzed histologically and serologically. Results Immunization of C57BL/6-derived mice transgenic for human HLA,DR4 with 70K and either CFA or U1 RNA led to anti-70K antibodies in 62% of mice (21 of 34), and diversified anti-RNP immune responses. MCTD-like lung disease also developed in 50% of immunized mice (17 of 34), and anti-70K antibodies were strongly correlated with lung disease. CFA and U1 RNA were comparably able to induce this syndrome. Mice deficient in Toll-like receptor 3 (TLR-3) also developed this same syndrome when immunized with 70K and CFA. However, TLR-3,/, mice failed to develop MCTD-like lung disease when treated with 70K and U1 RNA. Rather, TLR-3,/, mice immunized with 70K and U1 RNA developed an autoimmune syndrome characterized by glomerulonephritis typical of SLE. Conclusion Exposure to 70K in an appropriate context is sufficient to induce autoimmunity and target organ injury consistent with MCTD. This system represents a new model of autoimmune interstitial lung disease, and establishes a closer link between anti-70K immunity and MCTD-like lung disease. Of note, changes in innate immune signaling can cause the same trigger to lead to the development of SLE-like nephritis rather than MCTD-like lung disease. [source] The microstratigraphic record of abrupt climate changes in cave sediments of the Western MediterraneanGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 5 2001Marie-Agnès Courty The purpose of this paper is to illustrate how calcareous sediments from Pleistocene and Holocene rockshelters and open caves of the Western Mediterranean can provide a stratigraphic record of abrupt climate change. The method proposed here is based on microstratigraphic examination of sedimentary sequences using microscopic techniques. The most important processes for characterizing the sensitivity of each cave to climate variables are: (1) the modes and rate of carbonate sediment production, (2) the nature and intensity of the pedogenic processes responsible for the synchronous alteration of carbonate materials (either those derived from the cave walls or those deposited on the ground surface), and (3) the supply of allogenic sediments, particularly by eolian activity. The cave sediment sequences presented record the marked coolings known as Dansgaard-Oeschger stadials and Heinrich events that occurred during the Pleistocene and the Holocene, as demonstrated by the high resolution records from ice and deep sea cores. At Abric Romanì in northeastern Spain, a series of sharp climatic deteriorations of increasing severity is shown to have occurred synchronously with the transition from the Middle to the Upper Paleolithic, with a period of seasonal frost and strong winds at ca. 37,000 yr B.P., tentatively correlated with Heinrich event 4. At Pigeon Cave, Taforalt (northern Morocco), the transition from the Aterian to Ibero-Maurusian/Epipalaeolithic cultures is dated to around 24,000,20,000 yr B.P. and is punctuated by a series of short cold pulses with evidence for seasonal freezing, soil erosion, and minimal evapotranspiration. In El Miron cave in north-central Spain, the exceptional nature of the Younger Dryas cooling produced a marked destabilization of the cave walls and roof. At El Miron, the stratigraphic evidence for sediment removal due to the rapid percolation of snow melt under a degraded soil cover allows us to reconstruct the nature of the negative excursion at ca. 8200 yr B.P. This example also illustrates how climate-controlled pedogenic processes can create a stratigraphic signature which has often been confused with a sedimentary hiatus. We conclude that cave sediments provide a valuable record of Pleistocene and Holocene climate changes. In appropriate contexts, these sequences allow us to examine the ecological stress generated by these unique global events at a local and regional level and improve our understanding of the complex anthropological processes that occurred at the same time. © 2001 John Wiley & Sons, Inc. [source] Contingent application of the cancellation editing operation: the role of semantic relatedness between risky outcomesJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 2 2004Nicolao Bonini Abstract This article presents findings on the restructuring component of the decision process. Two experiments are described employing hypothetical vacation choice dilemmas. The aim was to explore the conditions under which outcomes common to two risky prospects with the same probabilities of occurrence are or are not cancelled and how consequent decisions are influenced. The design of the options presented to participants was based on pilot work to establish appropriate contexts. The key independent variable was the semantic relatedness between outcomes of the same risky prospect. The main finding was that the participants did not cancel the outcome shared by two prospects when it was semantically related to another outcome within the same prospect. In this case, the prospect with greater risk was chosen significantly more frequently in comparison to when the common outcome was unrelated to other outcomes. An interpretation of the findings is presented in terms of contingent editing processes. Copyright © 2004 John Wiley & Sons, Ltd. [source] Dynamic or Static Capabilities?THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 5 2009Process Management Practices, Response to Technological Change Whether and how organizations adapt to changes in their environments has been a prominent theme in organization and strategy research. Within this research, there is controversy about whether organizational routines hamper or facilitate adaptation. Organizational routines give rise to inertia but are also the vehicles for change in recent work on dynamic capabilities. This rising interest in routines in research coincides with an increase in management practices focused on organizational routines and processes. This study explores how the increasing use of process management practices affected organizational response to a major technological change through new product developments. The empirical setting is the photography industry over a decade, during the shift from silver-halide chemistry to digital technology. The advent and rise of practices associated with the new ISO 9000 certification program in the 1990s coincided with increasing technological substitution in photography, allowing for assessing how increasing attention to routines through ISO 9000 practices over time affected ongoing responsiveness to the technological change. The study further compares the effects for the incumbent firms in the existing technology with nonincumbent firms entering from elsewhere. Relying on longitudinal panel data models as well as hazard models, findings show that greater process management practices dampened response to new generations of digital technology, but this effect differed for incumbents and nonincumbents. Increasing use of process management practices over time had a greater negative effect on incumbents' response to the rapid technological change. The study contributes to research in technological change by highlighting specific management practices that may create disconnects between firms' capabilities and changing environments and disadvantage incumbents in the face of radical technological change. This research also contributes to literature on organizational routines and capabilities. Studying the effects of increasing ISO 9000 practices undertaken in firms provides an opportunity to gauge the effects of systematic routinization of organizational activities and their effects on adaptation. This research also contributes to management practice. The promise of process management is to help firms adapt to changing environments, and, as such, managers facing technological change may adopt process management practices as a response to uncertainty and change. But managers must more fully understand the potential benefits and risks of process management to ensure these practices are used in the appropriate contexts. [source] | |||||||||||||