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151.
In recent years, Head Start's prominent role in preparing low‐income 4‐year‐olds for school has been affected by rapid growth in state‐funded pre‐K programs, some of which are based in public schools. This has led to questions about the comparative advantages of these two approaches to early education. An analysis of data from Tulsa, Oklahoma, indicates that the school‐based pre‐K program is more effective in improving early literacy outcomes, while Head Start is more effective in improving health outcomes. The two programs are comparable with regard to early math learning. Social–emotional effects are more subtle, but the school‐based pre‐K program has demonstrable positive effects, while the Head Start program does not. 相似文献
152.
The late Mousterian of Acheulian tradition (MTA) site of Pech-de-l'Azé 1 shows a very particular stratigraphic sequence characterized by numerous elements not usually found in Mousterian contexts such as avifauna exploitation and the use of hundreds of mineral pigments. Recent zooarchaeological and skeletochronological analyses provide new insights into the evolution of subsistence behaviors and settlement patterns of the Neanderthals that inhabited the shelter. Due to changes in hunting season, Neanderthals adapted their hunting strategies, exploiting various red deer populations which presented very different behavior. The evolution in the seasonal occupation of the shelter may have been the results of major modifications of its (series of roof collapsed) which induced a shrank in inhabitable space., which forced the Mousterians to adjust the way they used the cavity to its characteristics in order to optimize its exploitation. The conclusions underline the excellent adaptability of the Neanderthals to their physical environment. 相似文献
153.
154.
William Andrefsky Jr. 《Journal of Archaeological Research》2009,17(1):65-103
Researchers who analyze stone tools and their production debris have made significant progress in understanding the relationship
between stone tools and human organizational strategies. Stone tools are understood to be morphologically dynamic throughout
their use-lives; the ever-changing morphology of stone tools is intimately associated with the needs of tool users. It also
has become apparent to researchers that interpretations of lithic analysis are more productive when the unique contexts and
situations for which lithic artifacts were made, used, modified, and ultimately discarded are considered. This article reviews
the recent literature on stone tool production with an emphasis on raw material procurement, manufacturing techniques, and
tool maintenance processes as they relate to adaptive strategies of toolmakers and users. 相似文献
155.
156.
Rothstein WG 《Journal of the history of medicine and allied sciences》2012,67(4):515-552
This study found that the effect of socioeconomic status (SES) on mortality decreased steadily during the twentieth century. It examined trends in age-specific adult mortality rates for employed men and infants in a number of social classes based on occupation in England and Wales and for black, white, and immigrant nationality groups of men, women, and infants in the United States. Both countries experienced continuing decreases in mortality rates and narrowing of SES differences in mortality rates from 1920 to the end of the century. Most of the decrease and narrowing in England and Wales occurred before the establishment of the National Health Service and the unprecedented improvements in clinical and preventive medicine after midcentury. Current cancer mortality rates in both countries show no consistent relationship with SES. The very low mortality rates of some low SES immigrant nationality groups in the United States throughout the century demonstrate that other social factors can have a greater effect on health than SES. 相似文献
157.
Clare Tochilin William R. Dickinson Matthew W. Felgate Mark Pecha Peter Sheppard Frederick H. Damon Simon Bickler George E. Gehrels 《Journal of archaeological science》2012
Through use of methodology common in sedimentary geology, we apply U–Pb ages of detrital zircons to source nonlocal temper sand in an ancient ceramic assemblage recovered from Roviana Lagoon of the New Georgia Group in the Solomon Islands. Most potsherds from the Roviana Lagoon contain local volcanic sand as temper, but a small number of sherds contain anomalous granitic temper sand that does not appear to be local. To determine the origin of the anomalous temper, ages of zircons from the anomalous Roviana sherds are compared with ages of zircons in materials from Lizard Island off the Queensland coast and in sand from Muyuw Island in the Solomon Sea where generically similar granitic sands occur. U–Pb analyses of grains from the Roviana sherds yield Middle Miocene ages, while analyses of grains from Lizard Island granitic bedrock, sand, and local potsherds yield much older Permian-Triassic ages, disproving any possibility that the Roviana sherds were derived from Lizard Island, but suggesting local production of the Lizard Island sherds. Ages of grains in a sand sample from Muyuw Island are nearly identical to the ages of grains in the Roviana sherds. All grains in the Muyuw sand are Middle Miocene in age, overlapping closely with the Roviana age population. This strong similarity in detrital zircon signals indicates that the Roviana temper was likely derived from Muyuw Island sands. Our test case for the use of U–Pb ages of detrital zircons in sourcing temper sands is of only regional significance, and not of intrinsic global interest. The methodology, however, should find wide applicability for sourcing temper sands in many parts of the world, for it provides more specific data for the origins of tempers than either petrographic or chemical analysis. 相似文献
158.
159.
Multiple groups have interests that intersect within the field of deep submergence (beyond the 50 meter range of SCUBA) archaeology. These groups?? differing priorities present challenges for interdisciplinary collaboration, particularly as there are no established guidelines for best practices in such scenarios. Associating the term ??archaeology?? with projects directed at underwater cultural heritage that are guided by archaeologists poses a real risk to that heritage. Recognizing that the relevant professional organizations, local laws, and conventions currently have little ability to protect pieces of cultural heritage across disciplines and international boundaries, the authors propose institution-specific mechanisms, called Archaeology Review Boards, guided by local and international laws and conventions concerning cultural heritage, as the best means to provide oversight for academically centered archaeological activities at the local level. 相似文献
160.
Xiaozhou Ding Christopher Bollinger Michael Clark William Hoyt 《Journal of regional science》2024,64(1):207-237
In the past 50 years, a voluminous literature estimating the value of schools through capitalization in home prices has emerged. Prior research has identified capitalization using a variety of approaches including discontinuities caused by boundaries. Here, we use changes in school boundaries and the opening of a new school in Fayette County (Lexington), Kentucky to identify this capitalization. Critical to properly estimating the effect of redistricting is to account for when information on redistricting is available. We treat the information about the effects of zoning as occurring in three stages: announcement of the intent to open the new high school and redistricting, approval of the specific redistricting plan (map), and implementation (opening of the new high school and actual changes in boundaries). We find significant changes in values for homes redistricted from lower-performing schools and we find that this capitalization occurs well before implementation of the redistricting. As we show, failure to account for capitalization occurring before implementation will attenuate and even change the sign of capitalization. 相似文献