A two-sector dynamic general equilibrium model is developed "to investigate the direction of migration in response to differing demographic and consumption demand behavior, as well as variations in production conditions." The model, which involves a rural sector and an urban sector, incorporates "returns to scale and the natural rate of sectoral population growth as important determinants of the direction of migration, in addition to price and income elasticities, and the sectoral technical change rate with which...previous studies dealt." 相似文献
The 1970's has been a period in which three trends have coincided: housing prices have been escalating, wives have continued to enter the labor force, and legislation prohibiting discrimination in mortgage markets on the basis of sex and marital status has been enacted. In this paper, we examine the role of the two-earner family–one in which both husband and wife work–in the housing market of the 1970's, and the interrelation of this household type with other factors shaping the current high demand for housing. We also speculate on the role of the two-earner family in the housing market of the 1980's. We conclude that two-earner families are in a position to increase their housing outlays in the future, that the continued growth in the number of two-earner families will add to future housing demand, but that many two-earner families may be divorced couples of the future. This suggests that, while there will be a strong impact on single-family home demand, there will also be some restructuring of demand toward rental housing and cooperative/condominium ownership. 相似文献
Shell beads are well established in the archaeological record of sub-Saharan Africa and appear as early as 75,000 BP; however, most research has focused on ostrich eggshell (OES) and various marine mollusc species. Beads made from various land snails shells (LSS), frequently described as Achatina, also appear to be widespread. Yet tracking their appearance and distribution is difficult because LSS beads are often intentionally or unintentionally lumped with OES beads, there are no directly dated examples, and bead reporting in general is highly variable in the archaeological literature. Nevertheless, Achatina and other potential cases of LSS beads are present at over 80 archaeological sites in at least eight countries, spanning the early Holocene to recent past. Here, we collate published cases and report on several more. We also present a new case from Magubike Rockshelter in southern Tanzania with the first directly dated LSS beads, which we use to illustrate methods for identifying LSS as a raw material. Despite the long history of OES bead production on the continent and the abundance of land snails available throughout the Pleistocene, LSS beads appear only in the late Holocene and are almost exclusively found in Iron Age contexts. We consider possible explanations for the late adoption of land snails as a raw material for beadmaking within the larger context of environmental, economic, and social processes in Holocene Africa. By highlighting the existence of these artifacts, we hope to facilitate more in-depth research on the timing, production, and distribution of LSS beads in African prehistory. 相似文献
Sexual assault is a heinous crime that for decades had failed to receive needed attention on college campuses across the country.11. Nancy Chi Cantalupo, “Burying Our Heads in the Sand: Lack of Knowledge, Knowledge Avoidance, and the Persistent Problem of Campus Peer Sexual Violence,” 43 Loy. U. Chi. L.J. (2011) 205, 214–17.View all notes That changed on April 4, 2011, when the Department of Education's (ED) Office of Civil Rights (OCR) issued a “Dear Colleague” letter (DCL) on sexual harassment and violence, which purported to clarify “Title IX's requirements related to student-on-student sexual harassment, including sexual violence, and explains schools' responsibility to take immediate and effective steps to end sexual harassment and sexual violence.”22. Russlynn Ali, Assistant Secretary for Civil Rights, “Dear Colleague Letter from Assistant Secretary for Civil Rights,” Office for Civil Rights, U.S. Department of Education. Office of the Assistant Secretary, April 4, 2011, http://www2.ed.gov/about/offices/list/ocr/letters/colleague-201104_pg2.html. All subsequent references to this letter will refer to Ali, Sexual Assault Guidance, 2011.View all notes The intent of the letter to mete out swift justice for sexual assault survivors and to punish perpetrators and negligent institutions became immediately clear as the number of schools under OCR investigation began to swell. In response, colleges and universities have instilled a vast machinery of administrative procedures to adhere to the new requirements. At last count the OCR was conducting more than 300 investigations of nearly 200 colleges and school districts for the handling of sexual harassment and assault under Title IX.33. Tyler Kingkade, “There Are Far More Investigations of College Campuses under Title IX than Most People Know,” Huffington Post, June 16, 2016, http://www.huffingtonpost.com/entry/title-ix-investigations-sexual-harassment_us_575f4b0ee4b053d433061b3d.View all notes相似文献
The US–ROK alliance during the First Korean Nuclear Crisis provides the most likely case of high alliance cohesion. Curiously, however, instead of dancing to the American tune in their joint management of the Democratic People's Republic of Korea (DPRK) threat, the Republic of Korea (ROK) caused frequent policy collisions – supporting the US–DPRK negotiations at one point and opposing it at another – at the risk of jeopardizing its physical security. The main finding here is that the variations in the South Korean behavior were a function of their experience of status inconsistency. In particular, the ROK became compliant with the US–DPRK talks when it believed that its desired status marker of taking the leadership role in crisis management was within reach, and unyielding otherwise. These fluctuations ended up not only eroding the US–ROK alliance cohesion but also inhibiting a successful resolution of the crisis. All this bears directly on the fundamental question of whether international politics is to be understood in essentially realist terms. 相似文献
Bell, P.R., Burns, M.E. & Smith, E.T. October 2017. A probable ankylosaurian (Dinosauria, Thyreophora) from the Early Cretaceous of New South Wales, Australia. Alcheringa 42, 120–124. ISSN 0311-5518.
We describe an isolated osteoderm from the Albian Griman Creek Formation where it is exposed near the town of Lightning Ridge in central-northern New South Wales, Australia. Several lines of evidence allow referral of this element to the Ankylosauria—a group that epitomises body armour and ubiquitous osteodermal coverage among dinosaurs. Despite the abundant record of fossil vertebrates from this interval, ankylosaurians have not been previously reported, although, they have been described from penecontemporaneous deposits in western Queensland and Victoria. This discovery, therefore, provides an important link between the northerly faunas (including the Griman Creek Formation) that flourished at the edge of the epeiric Eromanga Sea, with those from the sub-polar rift-valley system of Victoria during the mid-Cretaceous.
Phil R. Bell [pbell23@une.edu.au], School of Environmental and Rural Science, University of New England, Armidale 2351, NSW, Australia; Michael E. Burns [mburns3@jsu.edu], Department of Biology, Jacksonville State University, 700 Pelham Rd N., Jacksonville, AL 36265-2138, USA; Elizabeth T. Smith [elizabethtsmith@exemail.com.au], Australian Opal Centre, Lightning Ridge 2834, NSW, Australia.相似文献