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121.
122.
Nicole Cook 《Area》2009,41(2):176-185
This paper explores the transition of talk to text in the process of performing and recording semi-structured interviews over the telephone. In particular, it considers the ways respondents and the materials enjoined in the process of interviewing exceed their role in the research process. Drawing on my experience of conducting telephone interviews in the UK, I position the interview as an uncertain encounter: one framed by earlier narrations as much as the aims and objectives of the research project; and an orientation towards 'talk' as much as the reduction of performance to text. Far from losing track of these uncertainties I argue that tape-recorders are well equipped to document these in/audible realms.  相似文献   
123.
Despite widespread media coverage of livestock-related issues and growing scientific evidence linking meat production and climate change, systematic content analysis of this relationship in media coverage has been surprisingly minimal. In this article, we combine actor-network theory with framing theory to develop the basis for “story-networks”—networks of actants and artifacts that shape how a media report or “story” is framed. We coded livestock-related articles from a major U.S. newspaper, the Los Angeles Times, over the 1999–2010 period to understand how various actants and artifacts shaped different story-networks. Just 5% of all livestock articles addressed connections with climate change; these articles focused on technology, lifestyle, or policy. Distinctive story-networks characterized each category, framing the livestock–climate change linkage as an issue to be addressed through either technological innovation, individual lifestyle choices, or policy action. In each story-network type, varying configurations of actants and artifacts were involved, including the cattle themselves.  相似文献   
124.
We investigate European summer (July–August) precipitation variability and its global teleconnections using the NCEP/NCAR reanalysis data (1950–2010) and a historical Coupled Model Intercomparison Project climate simulation (1901–2005) carried out using the ECHAM6/MPIOM climate model. A wavelike pattern is found in the upper tropospheric levels (200 hPa) similar to the summer circumglobal wave train (CGT) extending from the North Pacific to the Eurasian region. The positive phase of the CGT is associated with upper level anomalous low (high) pressure over western (eastern) Europe. It is further associated with a dipole-like precipitation pattern over Europe entailing significantly enhanced (reduced) precipitation over the western (eastern) region. The anomalous circulation features and associated summer precipitation pattern over Europe inverts for the negative CGT phase. Accordingly, the global teleconnection pattern of a precipitation index summarizing summer precipitation over Western Europe entails an upper level signature which consists of a CGT-like wave pattern extending from the North Pacific to Eurasia. The imprint of the CGT on European summer precipitation is distinct from that of the summer North Atlantic Oscillation, despite the two modes of variability bear strong similarities in their upper level atmospheric pattern over Western Europe. The analysis of simulated CGT features and of its climatic implications for the European region substantiates the existence of the CGT-European summer precipitation connection. The summer CGT in the mid-latitude therefore adds to the list of the modes of large-scale atmospheric variability significantly influencing European summer precipitation variability.  相似文献   
125.
Has the notion of ‘sea change’ and its considerable implications for non-metropolitan coastal Australia been exaggerated? In this article alternative perspectives of ‘sea change’ in Australia are reviewed, and the policy implications of each assessed. One perspective regards migration to coastal areas beyond the capital cities as incidental to continued metropolitan primacy and unlikely to affect or change Australia's overall urban or economic structure. The other considers the movement as a significant and enduring process with major environmental and socio-economic repercussions. With reference to research conducted for the National Sea Change Taskforce, the article finds partial support for both positions, leading to a more revealing understanding of ‘sea change’ in Australia. A set of policy responses, sensitive to the particular qualities of Australian coastal environments and communities, are proposed for consideration by all three tiers of government.  相似文献   
126.
Commercially available hydraulic total overburden pressure cells were installed in the sand drainage layer of a municipal solid waste landfill and monitored for a period of 3,110 days. Both overburden pressure and temperature were measured in the landfill as it was filled with compacted waste. Topographic surveys of the landfill were periodically conducted to measure the height of waste above the pressure cells and to determine the landfill volume for indirect unit weight estimation. The average ratio of measured to theoretically-predicted overburden pressure was 0.6, indicating that on average the pressure cells underestimated the load. The overburden pressure measured near the toe of the landfill was greater than that predicted by the unit weight of landfilled material, while most of the overburden pressure measurements further inside the landfill were less than predicted. Several possible causes for this phenomenon are discussed, including the uneven distribution of forces resulting from the heterogeneous nature of the waste and cover soil. The earth pressure cells were capable of detecting the placement of individual waste lifts.  相似文献   
127.
Arctic permafrost coasts are sensitive to changing climate. The lengthening open water season and the increasing open water area are likely to induce greater erosion and threaten community and industry infrastructure as well as dramatically change nutrient pathways in the near-shore zone. The shallow, mediterranean Arctic Ocean is likely to be strongly affected by changes in currently poorly observed arctic coastal dynamics. We present a geomorphological classification scheme for the arctic coast, with 101,447?km of coastline in 1,315 segments. The average rate of erosion for the arctic coast is 0.5?m? year?1 with high local and regional variability. Highest rates are observed in the Laptev, East Siberian, and Beaufort Seas. Strong spatial variability in associated database bluff height, ground carbon and ice content, and coastline movement highlights the need to estimate the relative importance of shifting coastal fluxes to the Arctic Ocean at multiple spatial scales.  相似文献   
128.
ABSTRACT

Echinoderms play important ecological roles in the benthic community, but the processes that regulate their distribution are still poorly understood. The aim of this study was to describe the community structure in the shallow rocky reefs of the Wellington region of central New Zealand. Five sites from a harbour and an open coast were surveyed for adult echinoderm density and habitat composition. Additionally, artificial collectors were deployed to assess recruitment patterns. Five taxa were responsible for the assemblage variation within sites and their abundance was highly correlated with habitat composition. Patiriella regularis was highly abundant in all sites, while Coscinasterias muricata and Evechinus chloroticus were dominant in the Harbour. Echinoderm settlement showed interannual variations, as well as differences between locations. There was a significant pulse of C. muricata settlers, while ophiuroids were present in lower numbers but constantly during the studied period. E. chloroticus settlement was sporadic and the absence of a juvenile cohort in the open coast sites suggests that recruitment might not occur for up to 4 years. The present study provides insights on the echinoderm assemblage in the shallow rocky reefs of the Wellington region and contributes to a better understanding of recruitment patterns shaping population structure.  相似文献   
129.
Successfully engaging target audiences represents a key challenge for environmental conservation projects. In this study, we examined 354 conservation projects implemented across the United States with the intention of systematically exploring the relationships between different forms of outreach (in particular, message content and delivery) and self-reported project outcomes. Using end-of-program retrospective surveys, we found that experiential engagement and directly demonstrating and/or communicating the ease of potential conservation actions were most consistently related to achieving desired project outcomes. Although it was thought to be largely effective by project managers, we found that focusing on equipping audiences with new knowledge was negatively related to conservation outcomes. Measured outreach variables explained between 15% and 17% of the variance in project outcomes, suggesting a wide variety of unmeasured factors at play. We discuss insights relevant to engaging target audiences in future U.S. conservation projects.  相似文献   
130.
The origin and the relationships between the high potassic (HKS) and potassic (KS) suites of the Roman Comagmatic Province and the nature of their primary magmas have been intensively debated over the past 35 years. We have addressed these problems by a study of mineralogy (olivine Fo92-87, Cr-spinel and diopside) and melt inclusions in olivine phenocrysts from a scoria sample of Montefiascone (Vulsini area). This rock is considered as one of the most primitive (MgO=13.5 wt%, NiO=340 ppm; Cr=1275 ppm) in the northern part of the Roman Comagmatic Province. The compositions of both the olivine and their melt inclusions are controlled by two main processes. In the case of the olivine Fo<90.5, fractional crystallization (olivine + diopside + minor spinel) was the principal mechanism of the magma evolution. The olivine (Fo92-90.5) and the Cr-spinel (Cr#=100. Cr/(Cr+Al)=63-73) represent a near-primary liquidus assemblage and indicate the mantle origin of their parental magmas. The compositions of melt inclusions in these olivine phenocrysts correspond to those of poorly fractionated H2O-rich ( 1 wt%) primary melts (MgO=8.4-9.7 wt%,FeOtotal=6-7.5 wt%). They evidence a wide compositional range (in wt%: SiO2=46.5-50, K2O=5.3-2.8, P2O5=0.4-0.2, S=0.26-0.12; Cl=0.05-0.03, and CaO/Al2O3= 0.8-1.15), with negative correlations between SiO2 and K2O, Al2O3 and CaO, as well as positive correlations between K2O, and P2O5, S, Cl, with nearly constant ratios between these elements. These results are discussed in terms of segregation of various mantle-derived melts. The high and constant Mg# [100.Mg/(Mg+Fe2+)] 73-75 of studied melts and their variable Si, K, P, Ca, Al, S contents could be explained by the melting of a refractory lithospheric mantle source, heterogeneously enriched in phlogopite and clinopyroxene (veined mantle source).  相似文献   
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