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1.
Policies concerning undocumented immigrants are inevitably ambivalent, creating uncertainty and confusion in the implementation process. We identify a clear example of this ambivalence —U.S. law setting standards for determining the credibility of asylum seekers—that resulted in an increase in asylum grants despite policymakers' intention to make it harder for individuals to obtain the status. We argue that this law, The REAL ID Act of 2005, sent mixed messages to immigration judges (IJs), street-level bureaucrats who implement immigration policy. It increased IJ discretion, but set vague limits. We theorize that IJs, behaving in a bounded rationality framework, use their professional legal training as a short-cut and look primarily to the courts for guidance. Our evidence supports our argument. After the passage of the REAL ID Act, IJ decision-making is more closely aligned with the preferences of their political and legal principals, and, in the final score, the federal circuit courts are the winners. 相似文献
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Rebecca Repper Melissa Kennedy Jane McMahon David Boyer Matthew Dalton Hugh Thomas David Kennedy 《Arabian Archaeology and Epigraphy》2022,33(1):3-22
A comprehensive remote sensing survey of AlUla County in north-west Saudi Arabia has revealed 32 examples of the ancient, stone-built animal traps known as ‘kites’. Noting that most (27) are located on the Ḥarrat ʿ Uwayriḍ, a satellite survey of parts of that lavafield outside of AlUla County was undertaken, identifying a further 175 kites. These show commonalities with ‘V-shaped’ kites previously identified in mountainous areas along the western extents of the Arabian Shield in the Sinai Peninsula, Negev Desert and south-west Saudi Arabia. A study of the form and placement of these kites in their ecological and geological contexts suggests that they are representative of a distinct complex, exhibiting sophisticated morphological adaptations to target specific games over similar terrain. 相似文献
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Invasive cordgrass (Spartina spp.) in south‐eastern Australia induces island formation,salt marsh development,and carbon storage 下载免费PDF全文
David M. Kennedy Teresa Konlechner Elisa Zavadil Michela Mariani Vanessa Wong Daniel Ierodiaconou Peter Macreadie 《Geographical Research》2018,56(1):80-91
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments. 相似文献
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David Kennedy 《Arabian Archaeology and Epigraphy》2012,23(2):145-155
The stone structures known as kites and found widely in ‘Arabia’, are one of the more intriguing archaeological traces in what are often arid and bleak landscapes. They were first reported from the air in 1927, and by 1995 — largely through interpretation of old aerial photographs — c.500 had been identified. Now (2012), remote‐sensing techniques of various kinds have produced a huge increase, to over 3000. Recent work has also extended the geographical spread of kites in ‘Arabia’, from south‐eastern Turkey and north‐western Iraq to central Yemen. Much detailed work will be required to develop and refine a typology for kites as a whole and to digest and present data from remote sensing on which specialists may build interpretations and explanations. Current tabulation and mapping, however, already reveal patterns, and the discovery of an unusual form in the desert between Damascus and Palmyra in Syria deserves special attention. 相似文献