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Elizabeth Griffin argues for international action to rescue astronomical observations from decay and obsolescence.  相似文献   
44.
This paper examines similarities and differences in the emergence of high-tech enterprise and the growth of associated industry in Cambridgeshire and Oxfordshire since the 1960s. These cases are viewed as instances of a generic phenomenon: the emergence and growth of the science-based ‘innovative milieu’. A conceptual scheme drawn from complexity studies is used to introduce explanatory coherence into the apparently scattered and disconnected factors relevant to the genesis of high-tech milieux.  相似文献   
45.
Illness and mortality related to heat and worsening air quality are core public health concerns associated with climate change projections. We examined the historical relationship between age- and cause-specific mortality rates from 1980 through 2006 and heat events at the 99th percentile of humidex values in the historic period from January 1, 1970 to December 31, 2006 in the greater Seattle area (King, Pierce and Snohomish counties), Spokane County, the Tri-Cities (Benton and Franklin counties) and Yakima County; the relative risks of mortality during heat events were applied to population and climate projections for Washington State to calculate number of deaths above the baseline (1980–2006) expected during projected heat events in 2025, 2045 and 2085. Three different warming scenarios were used in the analysis. Relative risks for the greater Seattle area showed a significant dose-response relationship between heat event duration and daily mortality rates for non-traumatic deaths for persons ages 45 and above, typically peaking at four days of exposure to humidex values above the 99th percentile. The largest number of projected excess deaths in all years and scenarios for the Seattle region was found for age 65 and above. Under the middle warming scenario, this age group is expected to have 96, 148 and 266 excess deaths from all non-traumatic causes in 2025, 2045 and 2085, respectively. We also examined projected excess deaths due to ground-level ozone concentrations at mid century (2045–2054) in King and Spokane counties. Current (1997–2006) ozone measurements and mid-twenty-first century ozone projections were coupled with dose-response data from the scientific literature to produce estimates overall and cardiopulmonary mortality. Daily maximum 8-h ozone concentrations are forecasted to be 16–28% higher in the mid twenty-first century compared to the recent decade of 1997–2006. By mid-century in King County the non-traumatic mortality rate related to ozone was projected to increase from baseline (0.026 per 100,000; 95% confidence interval 0.013–0.038) to 0.033 (95% CI 0.017–0.049). For the same health outcome in Spokane County, the baseline period rate of 0.058 (95% CI 0.030–0.085) was estimated increase to 0.068 (95% CI 0.035–0.100) by mid-century. The cardiopulmonary death rate per 100,000 due to ozone was estimated to increase from 0.011 (95% CI 0.005–0.017) to 0.015 (0.007–0.022) in King County, and from 0.027 (95% CI 0.013–0.042) to 0.032 (95% CI 0.015–0.049) in Spokane County. Public health interventions aimed at protecting Washington’s population from excessive heat and increased ozone concentrations will become increasingly important for preventing deaths, especially among older adults. Furthermore, heat and air quality related illnesses that do not result in death, but are serious nevertheless, may be reduced by the same measures.  相似文献   
46.
The consistency of the critical exponent in the power law relation between the stress drop of the earthquake and the lead time of the precursory seismic electric signal is checked using new data from the recent M w 4.9 earthquake of strike-slip mechanism that occurred on 12 November 2013 in northern Evia island, Greece and the megathrust M w 9.0 Tohoku earthquake on 11 March 2011, in Japan. For the first case, the derived exponent is in excellent agreement with previous ones obtained from all non thrust events analysed by the author and matches the value of critical exponent for fracture. On the other hand, the megathrust Tohoku earthquake follows the behaviour of all thrust events studied by the author, and thus, the calculated exponent significantly deviates from this critical value. The different behaviour between non thrust and thrust-type events could be attributed to the fact that thrust mechanism earthquakes usually occur in collision or subduction zones which are characterised by high accumulation of strain. However, a larger number of thrust events are required in order to obtain reliable results and shed light in the above experimental findings.  相似文献   
47.
Concentration data on up to 82 individual constituents in USGS Basalt BCR-1 have been collected from 1395 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as ± one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   
48.
Over the years, research on relocation activity has provided insights about the characteristics of firms and regions that drive relocation. The spatial dimensions of these relocation decisions, however, particularly within states or metropolitan areas, remain an understudied aspect of the relocation literature. There is also little work comparing the destinations of relocations originating from within metropolitan areas compared to relocation activity from other states. Given the theoretical and practical importance of higher resolution, comparative research on relocation activity within metropolitan areas, this article uses both areal and point-based spatial statistics to test hypotheses about similarities and differences in the relocation behavior of locally oriented and out-of-state businesses within the Phoenix, Arizona, metropolitan area. Analytical results highlight distinct differences in the destinations of relocation activity originating from within the metropolitan area compared to out-of-state relocation activity. Intrametropolitan relocations tend to locate in less expensive and racially and ethnically diverse neighborhoods, whereas out-of-state relocations locate in wealthier, well-known locations of the metropolitan area. Out-of-state relocations are also less likely to locate in the downtown core. This suggests that expensive smokestack-chasing efforts directed at attracting businesses from out of state are unlikely to help revitalize the downtown core.  相似文献   
49.
Suspended sediments (SS) from the Atchafalaya River (AR) and the Mississippi River and surficial sediment samples from seven shallow cross-shelf transects west of the AR in the northern Gulf of Mexico were examined using elemental (%OC, C/N), isotopic (δ13C, Δ14C), and terrigenous biomarker analyses. The organic matter (OM) delivered by the AR is isotopically enriched (∼−24.5‰) and relatively degraded, suggesting that soil-derived OM with a C4 signature is the predominant OM source for these SS. The shelf sediments display OC values that generally decrease seaward within each transect and westward, parallel to the coastline. A strong terrigenous C/N (29) signal is observed in sediments deposited close to the mouth of the river, but values along the remainder of the shelf fall within a narrow range (8-13), with no apparent offshore trends. Depleted stable carbon isotope (δ13C) values typical of C3 plant debris (−27‰) are found near the river mouth and become more enriched (−22 to −21‰) offshore. The spatial distribution of lignin in shelf sediments mirrors that of OC, with high lignin yields found inshore relative to that found offshore (water depth > 10 m).The isotopic and biomarker data indicate that at least two types of terrigenous OM are deposited within the study area. Relatively undegraded, C3 plant debris is deposited close to the mouth of the AR, whereas more degraded, isotopically enriched, soil-derived OM appears to be deposited along the remainder of the shelf. An important input from marine carbon is found at the stations offshore from the 10-m isobath. Quantification of the terrigenous component of sedimentary OM is complicated by the heterogeneous composition of the terrigenous end-member. A three-end-member mixing model is therefore required to more accurately evaluate the sources of OM deposited in the study area. The results of the mixing calculation indicate that terrigenous OM (soil-derived OM and vascular plant debris) accounts for ∼79% of the OM deposited as inshore sediments and 66% of OM deposited as offshore sediments. Importantly, the abundance of terrigenous OM is 40% higher in inshore sediments and nearly 85% higher in offshore sediments than indicated by a two-end-member mixing model. Such a result highlights the need to reevaluate the inputs and cycling of soil-derived OM in the coastal ocean.  相似文献   
50.
Prehistoric potters frequently tempered their pottery with sand, the provenance of which can be established petrographically. In the Tonto Basin of central Arizona, the bedrock geology is highly variable, giving rise to geographically unique sands. Zones of sands with similar compositions can be modeled at an archaeologically relevant scale. Here we use the actualistic petrofacies concept, the Gazzi–Dickinson point‐counting technique, and multivariate statistics to create a petrofacies model, then apply it to sand‐tempered utilitarian pottery recovered from three Tonto Basin project areas. Data analysis reveals strong temporal and spatial ceramic production and consumption patterns. Production of pottery for exchange was established in at least one petrofacies ca. A.D. 600–950, with increasing specialization through time. By ca. A.D. 1150, corrugated wares had been added, and specialized production by ware was established in two petrofacies. Provenance evidence suggests different regional affiliations for groups in different parts of the basin. © 2001 John Wiley & Sons, Inc.  相似文献   
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