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Square Mile (square + mile)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

LAND-USE DYNAMICS BEYOND THE AMERICAN URBAN FRINGE,

GEOGRAPHICAL REVIEW, Issue 3 2001
DAVID M. THEOBALD
ABSTRACT. A deficiency common to both the historical debates over loss of agricultural land and the current discussions of urbanization and sprawl is a limited understanding of land-use dynamics beyond the urban fringe. Data aggregated at the county level poorly capture the fine-grained pattern of land-use change beyond the dynamic urban-rural interface. Furthermore, current urban-based definitions are poorly suited to delineate these areas, and low-density, exurban land use is difficult to measure using existing land-cover databases. Urbanization and the conversion of once-agricultural or other natural resource lands to other uses has traditionally been tracked using urban areas, as delimited in the U.S. census. Urban densities are typically defined as areas with more than 1,000 people per square mile, or 1.6 people per acre (U.S. Census Bureau 2000). Assuming an average of 2.5 people per housing unit, this translates to roughly 0.7 units per acre, or approximately 1 unit per 1.6 acres. The analytical units used in the census, however, both overbound and underbound areas with urban densities. About one-third of urban areas in 1990 comprised lower-than-urban housing density, thanks to overbounding. But, then, one-third of locations that had urban-level housing densities failed to be included in urban areas as a result of underbounding, which, if counted, would have constituted another 18 million acres of urban area. An increase over time of the average number of acres required per housing unit in exurban and higher-density locations occurred in roughly one-third of U.S. counties from 1960 to 1990 and persisted from 1990 to 2000. In 2000 roughly 38 million acres were settled at urban densities, and nearly ten times that much land was settled at rates from low, exurban density (as low as one house per 40 acres) to higher rates (up to one per 10 acres). This represents a continuing encroachment on land previously given over to other uses,habitat or agriculture. Practitioners of natural resource management need to recognize the ubiquity of exurban development and better incorporate the fine-scale patterns of land use beyond the urban fringe. [source]

Changing Trends in Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome in the Population Aged 50 and Older

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2007
Sindy M. Paul MD
OBJECTIVES: To alert persons in the public and private healthcare professions to the increasing trends in higher proportions of persons aged 50 and older who are newly diagnosed with human immunodeficiency virus (HIV) and who are living with HIV and acquired immunodeficiency syndrome (AIDS). DESIGN: Data from the period 1992 through 2004 from the HIV/AIDS Reporting System (HARS) were analyzed. SETTING: New Jersey is the eleventh-most-populous state, with the highest density of persons per square mile. It also has the fifth-highest number of AIDS cases. PARTICIPANTS: All persons residing in New Jersey and reported to HARS with HIV infection or who are considered to have AIDS. MEASUREMENTS: Trends in persons aged 50 and older were compared with those in the population younger than 50 during 1992 through 2004 for the numbers of persons living with HIV/AIDS and the number of persons newly diagnosed with HIV infection. RESULTS: The proportion of all persons aged 50 and older living with HIV/AIDS in 2004 was significantly greater than the comparable proportion of persons in 1992. Proportionally, more persons were newly diagnosed with HIV who were aged 50 and older according to sex and for each of the three major race or ethnicity groups (white non-Hispanic, black non-Hispanic, and Hispanic) than were persons younger than 50. Each of these increases was statistically significant. CONCLUSION: HIV/AIDS social marketing campaigns should include images and issues related to older persons in educational and prevention efforts. New methods that reach older populations should be considered. Physicians and other healthcare providers should be made aware of their role in prevention and education about HIV. Testing of older populations with risk factors should be encouraged. [source]

Comparing Household Listing Techniques in a Rural Midwestern Vanguard Center of the National Children's Study

PUBLIC HEALTH NURSING, Issue 2 2009
Katie Dreiling
ABSTRACT The National Children's Study (NCS) is a longitudinal study that will examine the influence of environmental and social factors on the health and development of 100,000 children, following them from before birth until age 21. Proposed participant recruitment methods call for locating and listing all dwelling units (DUs) located within randomly selected segments within the 105 NCS sites. One of seven Vanguard Centers of the NCS includes four rural counties that span approximately 2,500 square miles. The size of this sampling area presents unique geographic challenges. In order to determine the most efficient method for listing DUs within this large area, a study was undertaken to investigate the differences in the percent of DUs identified and the cost of four different approaches. It compared the on-site listing method of physically identifying each DU with three other methods: plat maps, postal listings, and Geographic Information Systems (GIS)/satellite imagery techniques. The on-site method had the strongest , (.85) in terms of identifying true DUs. There was a moderate agreement (.59) with the plat map method, fair agreement (.34) with the postal method, and only a slight agreement (.14) with the GIS/satellite imagery method. The plat map, postal listing, and GIS/satellite methods were less time-consuming than the on-site method. [source]

Animal behaviour and marine protected areas: incorporating behavioural data into the selection of marine protected areas for an endangered killer whale population

ANIMAL CONSERVATION, Issue 2 2010
E. Ashe
Abstract Like many endangered wildlife populations, the viability and conservation status of ,southern resident' killer whales Orcinus orca in the north-east Pacific may be affected by prey limitation and repeated disturbance by human activities. Marine protected areas (MPAs) present an attractive option to mitigate impacts of anthropogenic activities, but they run the risk of tokenism if placed arbitrarily. Notwithstanding recreational and industrial marine traffic, the number of commercial vessels in the local whalewatching fleet is approaching the number of killer whales to be watched. Resident killer whales have been shown to be more vulnerable to vessel disturbance while feeding than during resting, travelling or socializing activities, therefore protected-areas management strategies that target feeding ,hotspots' should confer greater conservation benefit than those that protect habitat generically. Classification trees and spatially explicit generalized additive models were used to model killer whale habitat use and whale behaviour in inshore waters of Washington State (USA) and British Columbia (BC, Canada). Here we propose a candidate MPA that is small (i.e. a few square miles), but seemingly important. Killer whales were predicted to be 2.7 times as likely to be engaged in feeding activity in this site than they were in adjacent waters. A recurring challenge for cetacean MPAs is the need to identify areas that are large enough to be biologically meaningful while being small enough to allow effective management of human activities within those boundaries. Our approach prioritizes habitat that animals use primarily for the activity in which they are most responsive to anthropogenic disturbance. [source]