Non-urban Locations Research Articles

Abstract 2585: Disparities in Evaluation by Certified Primary Stroke Centers within the REGARDS cohort

Background: There are known disparities in stroke incidence and mortality on the basis of race, income, region, and population density. Disparate access to specialized stroke care may contribute to these disparities. We sought to evaluate access to Joint Commission certified primary stroke centers (PSC) by race, education, income, population density, and region within the REGARDS cohort. Methods: The REasons for Geographic and Racial Differences in Stroke (REGARDS) study is a prospective population-based cohort of adults 45 years or older. 30,239 participants were recruited between 1 2003 and October 2007. Participants are contacted at 6 month intervals to ascertain suspected stroke events. The analysis was limited to the first suspected stroke event for each subject between 12/9/2005 and 1/6/2011. Medical records were retrieved and we determined if the evaluating hospital was a certified PSC at the time of the event. Region was dichotomized to stroke-belt or non-belt. Population density was dichotomized to urban or non-urban. Subjects evaluated at a PSC were compared to those evaluated at a non-PSC. Multivariable regression was used to determine independent predictors of PSC evaluation. Results: There were 1000 suspected stroke events during the study interval, of which 204 were evaluated at a certified PSC. Women were less likely to be evaluated at a PSC than men, 17.8% vs 23.0% (p=0.04). Subjects with a history of stroke were less likely to be evaluated at a PSC than those without a history of stroke, 15.1% vs 21.6% (p=0.04). Subjects who reside in non-urban locations were less likely to be evaluated at a PSC than those in urban areas, 9.1% vs 23.9% (p<0.001). Subjects residing within the stroke belt were less likely to be evaluated at a PSC than those living in other regions, 14.7% vs 27.3% (p<0.001). In the univariate analyses, no disparities were found on the basis of race, education, or income. In the multivariable analysis, living in non-urban areas (OR 2.6, 95% CI 1.5-4.5), living within the stroke belt (OR 1.9, 95% CI: 1.3-2.7), and having a prior history of stroke (OR 2.2, 95% CI 1.3-3.7) predicted evaluation at non-certified hospitals. Conclusion: Disparities in evaluation by certified PSC’s are related to geographic factors, region and population density, but not to most individual characteristics including race, education, or income. Despite an increased burden of cerebrovascular disease in the stroke belt and in rural areas, subjects in these areas were less likely to be treated at certified hospitals. This may be attributable to a reduced number of stroke centers in these locations. Public policy and systems planning should ensure specialized stroke care is rapidly accessible in areas with the greatest need.

Social Behaviours Between Urban and Non-Urban Pre-School Children

This study explored the influence of the locations of the pre-schools upon the social behaviours and genders of pre-school children in urban and non-urban areas. Post-Occupancy Evaluation studies were conducted upon 494 children in 20 classrooms in 10 Malaysian public pre-schools in the Klang Valley. Data collection involved natural unobtrusive observation with video recordings upon the children's social behaviour during their recess (free play) time. The findings revealed varying degrees of differences. Also, overall behavioural pattern between genders in the same location differed; while of the same genders were almost identical in both the urban and the non-urban locations. Implications of the findings were discussed.

Human Capital in Remote and Rural Australia: The Role of Graduate Migration

ABSTRACTIn this paper we examine the spatial employment patterns of Australia's university graduates in nonurban locations. Using a 2006 data set recording the employment status of 65,661 university graduates 6 months after their graduation we examine how the personal and human capital characteristics of the individual university graduate affect the type of rural location into which he or she enters for employment purposes. The importance of identifying which types of graduates work where is essential for our understanding of the forces that are currently shaping the spatial distribution of human capital across Australia's regions. In order to do this we allocate postcode‐based data of graduate employment to one of five remoteness classes, as defined by the Australian Bureau of Statistics, that allow us to distinguish between different degrees of rurality. The postcode data are used to associate the ways in which the human capital characteristics of the graduate in terms of the types of university degrees awarded and the universities attended, as well as the personal characteristics of the graduate, are related to the degrees of rurality in his or her employment outcomes.

A lead isotopic assessment of tree bark as a biomonitor of contemporary atmospheric lead

The outermost bark layer of trees, predominantly Scots pine ( Pinus sylvestris), was sampled at 82 non-urban locations from six arbitrarily designated areas (Northwest, Northeast, Central Highlands, Central and East, Central and Southwest, Southeast), throughout Scotland during 2002–2003 and analysed for lead concentration and stable lead isotopes by flame atomic absorption spectrometry (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The mean lead concentration and mean 206Pb/ 207Pb ratio (± 1 standard deviation, SD) for bark samples from the areas were as follows: Northwest (8.0 mg kg − 1 , 1.121 ± 0.014, n = 17), Northeast (8.9 mg kg − 1 , 1.117 ± 0.012, n = 12), Central Highlands (11.3 mg kg − 1 , 1.130 ± 0.010, n = 11), Central and East (35.3 mg kg − 1 , 1.120 ± 0.007, n = 10), Central and Southwest (20.6 mg kg − 1 , 1.125 ± 0.018, n = 22) and Southeast (34.4 mg kg − 1 , 1.120 ± 0.005, n = 10), with an overall mean lead concentration of 18.5 mg kg − 1 (range 0.6–146 mg kg − 1 , median 8.4 mg kg − 1 ) and an overall mean 206Pb/ 207Pb ratio of 1.122 ± 0.014 (range 1.089–1.168, median 1.122). The overall mean 206Pb/ 207Pb ratio for bark was therefore significantly lower ( p < 0.01, t test) than the mean atmospheric 206Pb/ 207Pb ratio of 1.154 ± 0.006 (range 1.144–1.167, n = 50) and 1.154 ± 0.010 (range 1.134–1.171, n = 26) as determined in rainwater collected routinely at Glensaugh, Central Highlands, during 2002 and 2003, respectively. The bark 206Pb/ 207Pb values, 90% of which lay between 1.10 and 1.14, were more akin to those recorded for the atmosphere (via rainwater, atmospheric particulates, moss, etc.) at various locations throughout Scotland during the 1990s, a decade over which the use of leaded petrol (mean 206Pb/ 207Pb ratio = 1.076 ± 0.011) declined markedly before its complete withdrawal in 2000. This strongly suggests that the lead content and isotopic composition of tree bark from Scots pine, which reputedly sheds its outer layers every couple of years or so, reflect exposure to atmospherically deposited lead (in the atmosphere or soil) over a much longer time period than just the previous 2–3 years of exposure to contemporary atmospheric lead. The possible influence of soil lead upon tree bark through external attachment was not observed in a comparative sub-set study of 27 paired bark (mean 206Pb/ 207Pb ratio = 1.122 ± 0.016) and surface (0–2 cm) soil (mean 206Pb/ 207Pb ratio = 1.145 ± 0.022) samples, in only six cases (i.e. 22%) of which did the corresponding 206Pb/ 207Pb ratios agree within ± 2 SD. Likewise, bark 206Pb/ 207Pb values exhibited no discernible trend with distance from the nearest road, with similar average values for 0–20 m (1.123 ± 0.015, n = 34) and 20–700 m (1.122 ± 0.012, n = 48), although the corresponding mean (and median) lead concentration of 23.5 (10) mg kg − 1 vs. 14.9 (7.5) mg kg − 1 was slightly higher for the former. The influence of airborne dusts from waste deposits related to former mining/smelting of Wanlockhead/Leadhills lead ores ( 206Pb/ 207Pb = 1.170 ± 0.003) could be seen, however, in the sycamore bark lead concentrations of up to 3050 mg kg − 1 and 206Pb/ 207Pb ratios (1.168–1.171) observed at a distance of 0.5 km away.

Observations of fine and coarse particle nitrate at several rural locations in the United States

Nitrate comprises an important part of aerosol mass at many non-urban locations during some times of the year. Little is known, however, about the chemical form and size distribution of particulate nitrate in these environments. While submicron ammonium nitrate is often assumed to be the dominant species, this assumption is rarely tested. Properties of aerosol nitrate were characterized at several IMPROVE monitoring sites during a series of field studies. Study sites included Bondville, Illinois (February 2003), San Gorgonio Wilderness Area, California (April and July 2003), Grand Canyon National Park, Arizona (May 2003), Brigantine National Wildlife Refuge, New Jersey (November 2003), and Great Smoky Mountains National Park, Tennessee (July/August 2004). Nitrate was found predominantly in submicron ammonium nitrate particles during the Bondville and San Gorgonio (April) campaigns. Coarse mode nitrate particles, resulting from reactions of nitric acid or its precursors with sea salt or soil dust, were more important at Grand Canyon and Great Smoky Mountains. Both fine and coarse mode nitrate were important during the studies at Brigantine and San Gorgonio (July). These results, which complement earlier findings about the importance of coarse particle nitrate at Yosemite and Big Bend National Parks, suggest a need to more closely examine common assumptions regarding the importance of ammonium nitrate at non-urban sites, to include pathways for coarse mode nitrate formation in regional models, and to consider impacts of coarse particle nitrate on visibility. Because coarse particle nitrate modes often extend well below 2.5 μm aerodynamic diameter, measurements of PM 2.5 nitrate in these environments should not automatically be assumed to contain only ammonium nitrate.

Antibiotic resistance of faecal Escherichia coli from healthy volunteers from eight developing countries.

To determine the prevalence of antibiotic-resistant faecal Escherichia coli from adult volunteers from urban (U) areas in Kenya, Mexico, Peru and the Philippines, and non-urban (NU) locations in Curacao, Mexico, Venezuela, Ghana, Zimbabwe and the Philippines. Faecal samples of adult volunteers (n=1290) were analysed in one laboratory for the presence of antimicrobial-resistant E. coli using Eosin Methylene Blue agar plates containing, respectively, ampicillin, oxytetracycline, cefazolin, ciprofloxacin, gentamicin, chloramphenicol and trimethoprim at breakpoint concentrations. The mean age of the volunteers was approximately 35 years; most of them were female. Ciprofloxacin resistance was in the range 1%-63%: the highest percentages were found in the urban populations of Asia and South America. In Peru and the Philippines (U and NU), the prevalence of gentamicin resistance was >20%. Cefazolin resistance was the highest in the urban Philippines (25%). Higher prevalences for ampicillin, oxytetracycline and trimethoprim were found for urban areas compared with non-urban ones of Asia, Africa and South America, respectively (P<0.05). In the populations studied, antibiotic resistance in faecal E. coli from adult volunteers was emerging for cefazolin, gentamicin and ciprofloxacin and was high for the older drugs ampicillin, oxytetracycline, trimethoprim and chloramphenicol.

A wintertime PM 2.5 episode at the Fresno, CA, supersite

A winter PM 2.5 episode that achieved a maximum 24-h average of 138 μg m −3 at the Fresno Supersite in California's San Joaquin Valley between 2 and 12 January, 2000 is examined using 5-min to 1-h continuous measurements of mass, nitrate, black carbon, particle-bound PAH, and meteorological measurements. Every day PM 2.5 sampling showed that many episodes, including this one, are missed by commonly applied sixth-day monitoring, even though quarterly averages and numbers of US air quality standard exceedances are adequately estimated. Simultaneous measurements at satellite sites show that the Fresno Supersite represented PM 2.5 within the city, and that half or more of the urban concentrations were present at distant, non-urban locations unaffected by local sources. Most of the primary particles accumulated during early morning and nighttime, decreasing when surface temperatures increased and the shallow radiation inversion coupled to a valleywide layer. When this coupling occurred, nitrate levels increased rapidly over a 10–30 min period as black carbon and gaseous concentrations dropped. This is consistent with a conceptual model in which secondary aerosol forms above the surface layer and is effectively decoupled from the surface for all but the late-morning and early afternoon period. Primary pollutants, such as organic and black carbon, accumulate within the shallow surface layer in urban areas where wood burning and vehicle exhaust emissions are high. Such a model would explain why earlier studies find nitrate concentrations to be nearly the same among widely separated sites in urban areas, as winds aloft of 1 to 6 m s −1 could easily disperse the elevated aerosol throughout the valley.

NEAR‐STREAM LANDUSE EFFECTS ON STREAMWATER NUTRIENT DISTRIBUTION IN AN URBANIZING WATERSHED1

ABSTRACT: We investigated spatial and temporal relationships among surface and subsurface watershed attributes and stream nutrient concentrations in urbanizing Johnson Creek watershed in northern Oregon. We sampled stream water at eight urban and five nonurban locations from March 1998 through December 1999. We sampled eight wells distributed over the two primary aquifers in the watershed. Using a Geographic Information System (GIS), percentages of landuse attributes within a radius of 30, 91, and 152 m from each sample site were quantified. We analyzed relationships between (1) nutrient concentrations and percentage cover of different landuse attributes, and (2) nutrient concentrations and underlying hydrologic units. We did not find a significant relationship between ground water chemistry and stream water chemistry. We found elevated levels of phosphorus (P) concentrations correlated with urban landuse, while higher nitrogen (N) concentrations were correlated with nonurban (primarily agricultural) landuse. We concluded that elevated levels of N in nonurban areas of Johnson Creek watershed were associated with agricultural practices. We further concluded that urban development factors such as increases in storm drains, dry wells, and impermeable surfaces may be responsible for higher input of P to the stream in urbanizing areas of the Johnson Creek watershed.

CHARACTERIZATION OF ATMOSPHERIC DRY DEPOSITED PARTICLES AT URBAN AND NON-URBAN LOCATIONS

Microscopic techniques were used to size particles collected on a deposition surface and to generate mass size distributions of deposited particles sampled from urban and non-urban locations. The volume shape factor was defined as a conversion factor between the projected area diameter and equivalent volume diameter of a particle and was used as an indication of the irregularity of the particle shape. The average volume shape factor of deposited particles at the urban location (1.61±0.21) was higher than the average at the non-urban locations (1.16±0.10). This suggests that particles are more irregular in the urban areas. Since non-urban areas have less larger particles in ambient air, depositional mass-size distributions at the urban location had a larger average peak (58 μm) and average mass median diameter (49 μm) of coarse particle mode of the distributions than they did at non-urban locations (averaged 33 and 27 μm). Evaluation of correlation coefficients between parameters (wind speed, deposition flux, peak diamater, mass median diameter) indicates that there are more airborne coarse particles at urban locations than at non-urban locations and this distribution plays an important role in dry deposition. By directly observing the deposited particles, it was found that particles larger than 10 μm diameter contributed to more than 90% (in mass) of the atmospheric dry deposition even when ambient coarse particle concentration is low at non-urban locations.

Is ozone pollution affecting crop yields in China?

Newly available data from non‐urban locations in China along with regional model simulations suggest that ground‐level ozone may be sufficiently high to affect China's winter wheat production. As non‐urban ozone increases with industrialization, its effects on crops could hinder efforts to meet increasing food demands in the coming decades, in China.

Housing Images Portrayed in 50 Years of Picture Storybooks

Images of housing portrayed in preschool picture storybooks influence the developing concept of home. Storybooks contribute to children’s socialization and function as cultural artifacts. This content analysis study of 100 preschool storybooks about family life published in the United States over 50 years focused on three housing images found in text and illustrations: geographical location, dwelling type, and types of residential spaces where family activities were portrayed. Change over time was represented by publication dates grouped into five time periods.Two-way chi-square analyses found no significant differences among time periods infrequency of portrayed housing characteristics. The dominant image of single-family detached housing in non-urban locations with typical room types was consistent across 50 years. Storybook housing images were compared to changes in housing patterns in the U.S. Census.

Lead concentrations in tissues of fruit bats (Pteropus sp.) in urban and non-urban locations

Lead concentrations were measured in tissues from 37 fruit bats from the Brisbane area and 5 bats from non-urban areas. On the basis of toxicity levels of 25 ug per g of kidney and 10 ug per g of liver, 11 of the Brisbane bats had concentrations consistent with toxicity. Other Brisbane bats had very high lead concentrations in bone and teeth. The lead concentrations in the non-urban bats were very low. Lead concentrations in the fur were variable but were highly correlated with concentrations in bones and teeth, reflecting long-term exposure to lead. High concentrations of lead were recovered from fur washings, which correlated very highly with the concentrations in kidney and liver, reflecting more recent and continuing exposure to lead. The source of the lead was not verified but the atmosphere was the probable source. Measurement of lead concentrations in the fur and its washings would appear to provide a means of monitoring lead accumulation in the tissues of fruit bats over both the long and short term. Such measurements could be valuable in monitoring environmental exposure to lead.

PM10 source apportionment in California's San Joaquin valley

A PM10 (particulate matter with aerodynamic diameter equal to or less than 10 μm) aerosol study was carried out at six sites in California's San Joaquin Valley (SJV) from 14 June 1988 to 9 June 1989, as part of the 1988–1989 Valley Air Quality Study (VAQS). Concentrations of PM10 and PM2.5 (particles with aerodynamic diameters equal to or less than 2.5 μm) mass, organic and elemental carbon, nitrate, sulfate, ammonium and elements were determined in 24-h aerosol samples collected at three urban (Stockton, Fresno, Bakersfield) and three non-urban (Crows Landing, Fellows, Kern Wildlife Refuge) locations during this period. The sources which contributed to ambient concentrations of PM10 were determined by applying the Chemical Mass Balance (CMB) receptor model using the source profiles determined specifically for that study area. The VAQS data indicates the federal 24-h PM10 standard of 150 μg m −3 was exceeded at four out of the six sites and for reasons which differ by season and by spatial region of influence. The annual average source contributions to the PM10 at Bakersfield, the site with the highest annual average, were 54% from primary geological material, 15% from secondary ammonium nitrate, 10% from primary motor vehicle exhaust, 8% from primary construction; the remaining 4% was unexplained. The results of the source apportionment at all sites show that geological contributions (fugitive dust from tilling, roadways and construction) are largest in summer and fall months, while secondary ammonium nitrate contributions (deriving from direct emissions of ammonia and oxides of nitrogen from agricultural activities and engine exhaust) are largest during winter months.

On the spatial and temporal variations in atmospheric concentrations of hexachlorobenzene and hexachlorocyclohexane isomers at several locations in the province of Ontario, Canada

Hexachlorobenzene (HCB), as well as α- and γ-hexachlorocyclohexane (HCH) have been measured at seven sites in Ontario, Canada during the years 1985–1989. While two of the locations were close to a suspected source of the organochlorines, five were sites that reflected the non-urban airshed loadings which are considered to be regionally representative of the Great Lakes. At the non-urban locations, the γ-HCH (lindane) and α-HCH concentrations ranged from 15 to 190 pg m−3 (mean of 47 pg m−3) and 50 to 660 pg m−3 (mean of 240 pg m−3), respectively. The HCB concentrations varied from 20 to 310 pg m−3 (mean of 94 pg m−3). At the suspected source locations, the α:γ HCH ratio was less than unity while at locations distant from known or suspected sources, the α:γ ratio was usually greater than 7. At the non-urban locations, the highest concentrations of the α- and γ-HCH isomers were observed during the summer and the lowest concentrations were seen during the winter. The concentration of HCB, however, remained relatively constant throughout the year.

Cervical screening performance in general practice. An evaluation in a single health district

This paper describes a study of cervical screening in 50 general practices in the East Berkshire Health District over a period of 2 1/2 years. Six practices organized their own practice based screening scheme. Thirty-nine participated in a district organized scheme and five did not actively participate in any scheme. The proportion of women screened was highest among the practices which organized their own scheme. These practices were large, in non-urban locations and employed a practice nurse. In contrast, practices which had a poor record of screening were small, single handed, in an urban location and were unwilling to participate in a district call scheme or organize their own scheme. It is recommended that the practices which are prepared to organize their own screening programmes should be encouraged to do so. The resources which are saved could then be more usefully spent on providing assistance to the practices which do not offer a cervical screening service to women on their practice lists.

Atmospheric particle sulfur and sulfur dioxide relationships at urban and nonurban locations

The percentages of particle sulfur in total sulfur measured have been obtained from a number of studies conducted in the United States, Canada and Europe. Particle sulfur consistently makes up a much larger part of the total sulfur in the warmer than cooler months of the year at all locations. However, differences in absolute percentages of particle sulfur in total sulfur are observed among studies and some explanations for such differences are discussed. Particle sulfur can make a substantial contribution to light scattering and dry deposition over large areas of North America particularly during the warmer months of the year.

Surface Ozone and Peroxyacetyl Nitrate (PAN) Observations at Rural Locations in Alberta, Canada

In order to better understand and control photochemical air pollution generated under the cold, dry climatic conditions of Alberta, an extensive program of environmental research studies was initiated in 1975. One objective was to measure concentrations of surface ozone, peroxyacetyl nitrate (PAN), and other pollutants associated with urban and industrial developments and to predict future trends in photochemical air pollution. To enable predictions to be made it was necessary to delineate the contribution of background levels of ozone and PAN to the urban centers and to measure background concentrations in the presently remote northern areas of the province. Measurements were made at three remote locations: the Kananaskis Valley, Birch Mountain, and Bitumount, and at two nonurban locations, Kavanagh, and Bon Accord. Mean ozone concentration in remote locations in Alberta (50/sup 0/ N to 58/sup 0/ N) during spring and early summer months fell in the range of 11-46 ppB. Daily maxima in Pan concentrations, measured at a remote location in the Rocky Mountains, were generally less than 1 ppB. Elevated PAN concentrations of 2.2 and 2.3 ppB were measured on two days when smoke from forest fires, burning 350 km to the north, entered the area. This suggests a majormore » natural source for PAN together with medium range transport. 2 figures, 2 tables. (DP)« less

Sulfur and trace metal relationships in nonurban and marine aerosols studied using proton induced X-ray emission

Abstract As an example of the application of the PIXE analysis technique to the study of sulfur and related trace metals in aerosol samples from nonurban locations, results obtained from a remote continental station in the Southern Hemisphere, Chacaltaya Mountain near La Paz, Bolivia, and a mid-ocean station in the Atlantic of the Northern Hemisphere, at Bermuda, are compared. In Bolivian filter samples, the proportions of Si, K, Ca, Ti, Fe, Rb, and Sr are within the ranges expected from the subaerial erosion of major rock types of the earth's crust. However, the proportions, relative to Fe, of S, Cu, Zn, As, and Pb are enriched 10–100 times in comparison with the compositions of major rock types. In Bermuda cascade impactor samples summed over all particle sizes, the ratio S/Zn and the relative of K, Ca, and Fe resemble those observed in Bolivia. Total Fe concentrations in Bermuda average about 60 ng/m 3 , similar to concentrations observed in Bolivia. However, the ratios S/Fe and Zn/Fe are 10 times greater in Bermuda than in Bolivia, and these ratios are greatest for smallest particles and decrease sharply with increasing particle size. The higher S and Zn concentrations in Bermuda may result from the combined effect of natural processes which control the atmospheric enrichment of chalcophile elements and of long range transport from pollution sources in urban and industrial centers.

Summary of the California aerosol characterization experiment.

This report gives a brief summary of the experimental plan and the early results of field observations from the California Aerosol Characterization Experiment (ACHEX). The objectives of the program center on questions of the sources and evolution of aerosols in urban air, as they are superimposed on a natural background, particularly as they relate to visibilitydegradation. The project initially nvolved the use of an elaborately instrumented mobile laboratory combined with a fixed station in San Jose, in Pasadena, and in Riverside, and later incorporated several satellite monitoring stations in the Los Angeles Basin. Intensive field observationswere taken from July 1972 to November 1972 in several urban and nonurban locations between the San Francisco Bay area and the South Coast Basin, covering the Los Angeles area. In a second phase of the ACHEX, aerosols accompanying photochemical smog were studied intensively in the Los Angeles Basin during the period between July and October of 1973. The observations...

An investigation into regional transport of soot and sulfate aerosols

Daily measurements of soot and sulfate aerosols at urban and nonurban locations in Southern Sweden are used to demonstrate that an appreciable long range transport of these substances takes place with source regions in the SE-SW directions. Comparison with anthropogenic emissions shows that distant sources—more than 1000 km away—give significant contributions. The rate of formation of sulfate aerosols from oxidation of SO 2 has been studied. It has been found that, as a mean value for Swedish towns, only about 5 per cent of the emitted sulfur has been oxidized and formed sulfate aerosols within the first tens of minutes that the air parcel is still within the town. Total aerosol concentration has been estimated from visibility observations. A clear correlation between sulfate concentration and total aerosol mass has been found, although the mass of sulfate ions was only a small fraction of the total aerosol mass.