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131.
Are some American states inherently more innovative than others? This question has confounded researchers for more than four decades. In this study we develop a measure of collective policy innovation that measures formal cooperative policy arrangements among the states, compare the measure to existing measures of internal state policy innovation, and assess whether existing innovativeness measures explain policy cooperation among the states. This test of the innovativeness concept addresses internal and external validity concerns that have long plagued this research tradition. Our multivariate analyses indicate that policy innovativeness is often a statistically and substantively important determinant of compact participation. These results suggest that (i) innovativeness is a meaningful and durable state attribute, (ii) several existing indices successfully capture the underlying latent concept, and (iii) innovativeness provides analytic utility in multiple empirical contexts.  相似文献   
132.
In the face of the reemerging threat of preventable diseases and the simultaneous vaccine risk controversy, what explains variations in Americans’ policy preferences regarding childhood vaccinations? Using original data from a recent nationwide Internet survey of 1,213 American adults, this research seeks to explain differing public opinions on childhood vaccination policies and related issues of governance. As Mary Douglas and Aaron Wildavsky's grid‐group cultural theory of policy preference formation suggests, cultural biases have a significant impact on the formation of preferences toward various vaccination policies. Hierarchs are in support of mandatory vaccination, oppose religious and philosophical exemption, and believe the government should preside over vaccination‐related decisions. Fatalists strike a bold contrast in their opposition to mandatory vaccination policy and support for religious and philosophical exemptions and the role of parents in deciding on vaccinations. Falling between hierarchs and fatalists, egalitarian support for vaccinations is stronger than individualists‘.  相似文献   
133.
The Sanandaj-Sirjan zone of Iran is a metamorphic belt consisting of rocks which were metamorphosed under different pressure and temperature conditions and intruded by various plutons ranging in composition from gabbro to granite. The majority of these granitoids formed along the ancient active continental margin of the Neo-Tethyan ocean at the southeastern edge of the central Iranian microplate. Geochronological data published in recent years indicate periodic plutonism lasting from Carboniferous through Mesozoic to late-Paleogene times (from ca. 300 to ca. 35 Ma) with climax activity during the mid- and late-Jurassic. The age constraints for plutonic complexes, such as Siah-Kouh, Kolah-Ghazi, Golpayegan (Muteh), Azna, Aligoodarz, Astaneh, Borujerd, Malayer (Samen), Alvand, Almogholagh, Ghorveh, Saqqez, Marivan, Naqadeh and Urumieh, clearly indicate the periodic nature of magmatism. Therefore, the Sanandaj-Sirjan zone preserves the record of magmatic activity of a complete orogenic cycle related to (1) Permocarboniferous(?) rifting of Gondwana and opening of the Neo-Tethyan ocean, (2) subduction of the oceanic crust, (3) continental collision and (4) post-collision/post-orogenic activities. The formation of the Marivan granitoids, northwestern Sanandaj-Sirjan zone, for which we present U-Pb zircon and titanite ages of ca. 38 Ma, can be related to the collisional and post-collisional stages of this orogenic cycle.  相似文献   
134.
Achieving the Millennium Development Goal of halving poverty will require simultaneous action on two separate fronts: helping poor people escape from poverty, and stemming the flow of people into poverty. This article examines forty Peruvian communities, and finds that descents into poverty have occurred alongside escapes in every one of them. Escape and descent are asymmetric in terms of reasons: while one set of reasons is responsible for escapes from poverty, another and different set of reasons is associated with descent. Making progress in poverty reduction will require measures to accelerate escapes whilst at the same time slowing down descents. The article looks at the different policies which will be required to serve these two separate purposes.  相似文献   
135.
ABSTRACT We investigate how cross‐country differences in firms' fixed set‐up costs affect the trade‐off between global efficiency and spatial equity. Our analysis reveals that the standard assumption of symmetry in set‐up costs masks the existence of an interesting effect: the range of available varieties depends on the spatial distribution of firms. In such a setting, where the market outcome leads to excessive agglomeration in the symmetric case, a planner may opt for asymmetric set‐up costs and even more agglomeration. We show that the planner will always favor lower set‐up costs in the large country with more agglomeration when the consumer's marginal preference for variety is high, or with less agglomeration when the consumer's marginal preference for variety is low.  相似文献   
136.
The essay shows that the axiomatics of the systemic‐cybernetic‐biological theory of self‐organization by Humberto Maturana and Francisco Varela have their roots in the philosophy of German Idealism. Especially the completely subject‐centered philosophy of Johann Gottlieb Fichte already contains the central axiomatics of Maturana and Varela.  相似文献   
137.
Fractures are important conduits for fluid flow in the Earth's crust. To better understand the spatial and temporal relations among fracturing, fracture sealing, and fluid flow, we have studied fractures, faults, and veins in a large dome (Jabal Akhdar) in the Oman mountains. Our work combines the results of meso‐ and microstructural analyses and stable isotope analyses. Seven generations of fractures and veins have been identified in the carbonate‐dominated dome. The earliest generations of veins developed during extension and subsidence of the Mesozoic basin. These veins formed in the inclined segments of bedding‐parallel stylolites and in extensional fractures that are perpendicular to bedding (#1 and #2, respectively). These extension‐related veins are truncated by bedding‐parallel veins (#4) that formed during top‐to‐north bedding‐parallel shear of both the northern and southern limbs of the dome. These veins are consistent with a change in stress regime and may be related to an earlier generation of strongly deformed pinch‐and‐swell veins (#3) that are exposed locally on the southern limb of the dome. Normal faults contain a set of en‐echelon tension gashes (#5) and veins emplaced in dilational jogs along the fault planes (#6). In the northern part of the dome, veins (#7) associated with thrusts post‐date the normal faults. Samples of veins and their host rocks were analyzed to provide information on fluid‐rock interaction in the dome and the scale(s) of fluid movement. Oxygen isotope values range from +16.2 to +29.3‰; carbon isotope values range from 0 to +3.6‰. The results of the structural and isotopic analyses are consistent with the early veins (#2–#5) having precipitated from overpressured fluid in a isotopically rock‐buffered system. During normal faulting (#5 and #6), a more open system allowed external fluid to infiltrate the dome at drained conditions and precipitate the youngest sets of veins (#6 and #7).  相似文献   
138.
The Trèves zinc–lead deposit is one of several Mississippi Valley‐type (MVT) deposits in the Cévennes region of southern France. Fluid inclusion studies show that the ore was deposited at temperatures between approximately 80 and 150°C from a brine that derived its salinity mainly from the evaporation of seawater past halite saturation. Lead isotope studies suggest that the metals were extracted from local basement rocks. Sulfur isotope data and studies of organic matter indicate that the reduced sulfur in the ores was derived from the reduction of Mesozoic marine sulfate by thermochemical sulfate reduction or bacterially mediated processes at a different time or place from ore deposition. The large range of δ34S values determined for the minerals in the deposit (12.2–19.2‰ for barite, 3.8–13.8‰ for sphalerite and galena, and 8.7 to ?21.2‰ for pyrite), are best explained by the mixing of fluids containing different sources of sulfur. Geochemical reaction path calculations, based on quantitative fluid inclusion data and constrained by field observations, were used to evaluate possible precipitation mechanisms. The most important precipitation mechanism was probably the mixing of fluids containing different metal and reduced sulfur contents. Cooling, dilution, and changes in pH of the ore fluid probably played a minor role in the precipitation of ores. The optimum results that produced the most metal sulfide deposition with the least amount of fluid was the mixing of a fluid containing low amounts of reduced sulfur with a sulfur‐rich, metal poor fluid. In this scenario, large amounts of sphalerite and galena are precipitated, together with smaller quantities of pyrite precipitated and dolomite dissolved. The relative amounts of metal precipitated and dolomite dissolved in this scenario agree with field observations that show only minor dolomite dissolution during ore deposition. The modeling results demonstrate the important control of the reduced sulfur concentration on the Zn and Pb transport capacity of the ore fluid and the volumes of fluid required to form the deposit. The studies of the Trèves ores provide insights into the ore‐forming processes of a typical MVT deposit in the Cévennes region. However, the extent to which these processes can be extrapolated to other MVT deposits in the Cévennes region is problematic. Nevertheless, the evidence for the extensive migration of fluids in the basement and sedimentary cover rocks in the Cévennes region suggests that the ore forming processes for the Trèves deposit must be considered equally viable possibilities for the numerous fault‐controlled and mineralogically similar MVT deposits in the Cévennes region.  相似文献   
139.
Geochemical and isotopic studies have been undertaken to assess the origin of CO2‐rich waters issuing in the northern part of Portugal. These solutions are hot (76°C) to cold (17°C) Na–HCO3 mineral waters. The δ2H and δ18O signatures of the mineral waters reflect the influence of altitude on meteoric recharge. The lack of an 18O‐shift indicates there has been no high temperature water–rock interaction at depth, corroborating the results of several chemical geothermometers (reservoir temperature of about 120°C). The low 14C activity (up to 9.9 pmC) measured in some of the cold CO2‐rich mineral waters (total dissolved inorganic carbon) is incompatible with the presence of 3H (from 1.7 to 4.1 TU) in those waters, which indicates relatively short subsurface circulation times. The δ13C values of CO2 gas and dissolved inorganic carbon range between ?6‰ and ?1‰ versus Vienna‐Peedee Belemnite, indicating that the total carbon in the recharge waters is being diluted by larger quantities of CO2 (14C‐free) introduced from deep‐seated (upper mantle) sources, masking the 14C‐dating values. The differences in the 87Sr/86Sr ratios of the studied thermal and mineral waters seem to be caused by water–rock interaction with different granitic rocks. Chlorine isotope signatures (?0.4‰ < δ37Cl < +0.4‰ versus standard mean ocean chloride) indicate that Cl in these waters could be derived from mixing of a small amount of igneous Cl from leaching of granitic rocks.  相似文献   
140.
This paper explores the usefulness of employing the concept of social capital within a research project investigating the best ways of meeting the health and well‐being needs of young people living in rural Wales. The first part of the paper provides an overview of some of the current research exploring the relationship between social capital, health and young people. The second part provides an overview of findings from an action research project to illustrate how social capital is conceived and applied in this context. It concludes by stating that children and young people do actively generate, draw upon and negotiate their own social capital, and that this is an under‐utilised resource in terms of promoting health and well‐being.  相似文献   
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