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Concerns for river health in the Murray-Darling Basin (MDB) area and shifting priorities for water use have led to a significant process of water reform over the last decade. The MDB area, also known as the food bowl of Australia, produces much of the country's food and is home to a significant portion of the population. A long-term drought, historical over-allocation of water for irrigation and climate variability have led to mounting concerns about the long-term viability of the rivers. While the reform process has resulted in the Commonwealth government taking control of the rivers from the States, it has also been influenced by changes in governments and consequent shifts in water allocation priorities from a privileging of agriculture to a broader approach encompassing economic, environmental and social concerns. This had led to uncertainty for the people and communities in the Basin and some confusion between the various layers of governance structures. This paper presents the results of exploratory research conducted with key, high-level stakeholders involved in water reform to examine their perceptions of the evolving water policy process. Despite agreement amongst stakeholders that returning water to the environment to ensure river health is critical, our research reveals significant tensions between stakeholders concerning the evolving process, particularly centred on the potential social outcomes and fairness and equity. This suggests the need for more integrated and transparent governance structures, attention to levels of trust between partners and a common vision that incorporates environmental, economic and social goals.  相似文献   
94.
A fast, automated, gas chromatographic system for the airborne measurement of PAN and a series of its homologues is described and its performance is evaluated. Response factors for PAN, PPN, APAN, PiBN, and MPAN have been determined and are discussed with regard to ECD response and to potential losses in the analytical system. Calibration methods used for these tasks are described and compared. The results from this work should help investigators who are employing the widely used GC/ECD method for the measurement of peroxyacyl nitrates to evaluate peaks of PAN homologues that cannot be calibrated for by using the reported response factors.  相似文献   
95.

We present fully three-dimensional equations to describe the rotations of a body made of a deformable mantle and a fluid core. The model in its essence is similar to that used by INPOP19a (Integration Planétaire de l’Observatoire de Paris) Fienga et al. (INPOP19a planetary ephemerides. Notes Scientifiques et Techniques de l’Institut de Mécanique Céleste, vol 109, 2019), and by JPL (Jet Propulsion Laboratory) (Park et al. The JPL Planetary and Lunar Ephemerides DE440 and DE441. Astron J 161(3):105, 2021. doi:10.3847/1538-3881/abd414), to represent the Moon. The intended advantages of our model are: straightforward use of any linear-viscoelastic model for the rheology of the mantle; easy numerical implementation in time-domain (no time lags are necessary); all parameters, including those related to the “permanent deformation”, have a physical interpretation. The paper also contains: (1) A physical model to explain the usual lack of hydrostaticity of the mantle (permanent deformation). (2) Formulas for free librations of bodies in and out-of spin-orbit resonance that are valid for any linear viscoelastic rheology of the mantle. (3) Formulas for the offset between the mantle and the idealised rigid-body motion (Peale’s Cassini states). (4) Applications to the librations of Moon, Earth, and Mercury that are used for model validation.

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We examine whether conservative white males are more likely than are other adults in the U.S. general public to endorse climate change denial. We draw theoretical and analytical guidance from the identity-protective cognition thesis explaining the white male effect and from recent political psychology scholarship documenting the heightened system-justification tendencies of political conservatives. We utilize public opinion data from ten Gallup surveys from 2001 to 2010, focusing specifically on five indicators of climate change denial. We find that conservative white males are significantly more likely than are other Americans to endorse denialist views on all five items, and that these differences are even greater for those conservative white males who self-report understanding global warming very well. Furthermore, the results of our multivariate logistic regression models reveal that the conservative white male effect remains significant when controlling for the direct effects of political ideology, race, and gender as well as the effects of nine control variables. We thus conclude that the unique views of conservative white males contribute significantly to the high level of climate change denial in the United States.  相似文献   
98.
Grass seed farmers have burned their fields in Idaho and Washington State for decades. Field burning, however, creates small particulate matter air pollution, thus engendering a growing public backlash by the 1990s that manifested itself in new clean air advocacy groups. The new groups’ push for policy change eventually met with significant success in both cases. How did each set of advocates approach the challenge of policy change? More specifically, what kinds of policy venues did each group choose and why? This research uses the cases to explore and explain each clean air group's choices vis-à-vis hypotheses of venue choice. Three hypotheses are tested—Schattschneider's (1960 Schattschneider , E. E. 1960 . The semisovereign people . New York , NY : Holt, Rinehart, and Winston . [Google Scholar]) “expanded scope of conflict” thesis, ACF's (Sabatier and Jenkins-Smith 1999 Sabatier , P. , and H. Jenkins-Smith . 1999 . The advocacy coalition framework: An assessment . In Theories of the policy process , ed. P. A. Sabatier , 117166 . Boulder , CO : Westview Press . [Google Scholar]) contention that groups strategically apply their resources in order to increase the likelihood of achieving their primary goal(s), and Pralle's (2003 Pralle , S. B. 2003 . Venue shopping, political strategy, and policy change . J. Public Policy 23 : 233260 .[Crossref] [Google Scholar], 2010 Pralle , S. B. 2010 . Shopping around: Environmental organizations and the search for policy venues . In Advocacy organizations and collective action , ed. A. Prakash and M. K. Gugerty , 177203 . Cambridge , MA : Cambridge University Press .[Crossref] [Google Scholar]) thesis that internal group constraints deter groups from moving into new venues.  相似文献   
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Ti-in-zircon thermometry: applications and limitations   总被引:11,自引:5,他引:11  
The titanium concentrations of 484 zircons with U-Pb ages of ∼1 Ma to 4.4 Ga were measured by ion microprobe. Samples come from 45 different igneous rocks (365 zircons), as well as zircon megacrysts (84) from kimberlite, Early Archean detrital zircons (32), and zircon reference materials (3). Samples were chosen to represent a large range of igneous rock compositions. Most of the zircons contain less than 20 ppm Ti. Apparent temperatures for zircon crystallization were calculated using the Ti-in-zircon thermometer (Watson et al. 2006, Contrib Mineral Petrol 151:413–433) without making corrections for reduced oxide activities (e.g., TiO2 or SiO2), or variable pressure. Average apparent Ti-in-zircon temperatures range from 500° to 850°C, and are lower than either zircon saturation temperatures (for granitic rocks) or predicted crystallization temperatures of evolved melts (∼15% melt residue for mafic rocks). Temperatures average: 653 ± 124°C (2 standard deviations, 60 zircons) for felsic to intermediate igneous rocks, 758 ± 111°C (261 zircons) for mafic rocks, and 758 ± 98°C (84 zircons) for mantle megacrysts from kimberlite. Individually, the effects of reduced or , variable pressure, deviations from Henry’s Law, and subsolidus Ti exchange are insufficient to explain the seemingly low temperatures for zircon crystallization in igneous rocks. MELTs calculations show that mafic magmas can evolve to hydrous melts with significantly lower crystallization temperature for the last 10–15% melt residue than that of the main rock. While some magmatic zircons surely form in such late hydrous melts, low apparent temperatures are found in zircons that are included within phenocrysts or glass showing that those zircons are not from evolved residue melts. Intracrystalline variability in Ti concentration, in excess of analytical precision, is observed for nearly all zircons that were analyzed more than once. However, there is no systematic change in Ti content from core to rim, or correlation with zoning, age, U content, Th/U ratio, or concordance in U-Pb age. Thus, it is likely that other variables, in addition to temperature and , are important in controlling the Ti content of zircon. The Ti contents of igneous zircons from different rock types worldwide overlap significantly. However, on a more restricted regional scale, apparent Ti-in-zircon temperatures correlate with whole-rock SiO2 and HfO2 for plutonic rocks of the Sierra Nevada batholith, averaging 750°C at 50 wt.% SiO2 and 600°C at 75 wt.%. Among felsic plutons in the Sierra, peraluminous granites average 610 ± 88°C, while metaluminous rocks average 694 ± 94°C. Detrital zircons from the Jack Hills, Western Australia with ages from 4.4 to 4.0 Ga have apparent temperatures of 717 ± 108°C, which are intermediate between values for felsic rocks and those for mafic rocks. Although some mafic zircons have higher Ti content, values for Early Archean detrital zircons from a proposed granitic provenance are similar to zircons from many mafic rocks, including anorthosites from the Adirondack Mts (709 ± 76°C). Furthermore, the Jack Hills zircon apparent Ti-temperatures are significantly higher than measured values for peraluminous granites (610 ± 88°C). Thus the Ti concentration in detrital zircons and apparent Ti-in-zircon temperatures are not sufficient to independently identify parent melt composition. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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