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1.
J Environ Health ; 75(6): 60-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23397651

RESUMO

Pennsylvania has over three million rural residents using private water wells for drinking water supplies but is one of the few states that lack statewide water well construction or management standards. The study described in this article aimed to determine the prevalence and causes of common health-based pollutants in water wells and evaluate the need for regulatory management along with voluntary educational programs. Water samples were collected throughout Pennsylvania by Master Well Owner Network volunteers trained by Penn State Extension. Approximately 40% of the 701 water wells sampled failed at least one health-based drinking water standard. The prevalence of most water quality problems was similar to past studies although both lead and nitrate-N were reduced over the last 20 years. The authors' study suggests that statewide water well construction standards along with routine water testing and educational programs to assist water well owners would result in improved drinking water quality for private well owners in Pennsylvania.


Assuntos
Poluentes da Água/análise , Qualidade da Água/normas , Poços de Água , Códigos de Obras , Água Potável , Humanos , Nitratos/análise , Pennsylvania , Prevalência , Política Pública , Saúde da População Rural , Microbiologia da Água , Poluentes Químicos da Água/análise , Abastecimento de Água/normas
2.
J Mark Res ; 48: S23-S37, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24634544

RESUMO

Many people fail to save what they need to for retirement (Munnell, Webb, and Golub-Sass 2009). Research on excessive discounting of the future suggests that removing the lure of immediate rewards by pre-committing to decisions, or elaborating the value of future rewards can both make decisions more future-oriented. In this article, we explore a third and complementary route, one that deals not with present and future rewards, but with present and future selves. In line with thinkers who have suggested that people may fail, through a lack of belief or imagination, to identify with their future selves (Parfit 1971; Schelling 1984), we propose that allowing people to interact with age-progressed renderings of themselves will cause them to allocate more resources toward the future. In four studies, participants interacted with realistic computer renderings of their future selves using immersive virtual reality hardware and interactive decision aids. In all cases, those who interacted with virtual future selves exhibited an increased tendency to accept later monetary rewards over immediate ones.

3.
J Environ Qual ; 35(2): 433-41, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16455843

RESUMO

For decades, the hardwood forests of northern Pennsylvania have been subjected to chronic atmospheric loading of acidifying agents. On marginal, high-elevation, unglaciated sites, sugar maples (Acer saccharum Marsh.) have experienced severe decline symptoms and mortality. Accelerated soil acidification, base cation leaching, and increased availability of toxic metals have been suggested as predisposing factors contributing to this decline. Manganese, an essential micronutrient, is also a potentially phytotoxic metal that may be a factor associated with poor sugar maple health on soils vulnerable to acidification from anthropogenic sources. We measured Mn levels in four compartments of the soil-tree system (soil, foliage, xylem wood, and sap) on three sugar maple stands in northern Pennsylvania. Two stands were classified as declining and one was in good health. Negative correlations were found between soil pH and Mn levels in the soil, foliage, sap, and xylem wood. Levels of Mn in these pools were consistently higher on declining sites, which correspondingly exhibited lower levels of Ca and Mg. Species differences between red maple (Acer rubrum L.) and sugar maple at the two declining sites suggested different tolerances to excessive Mn. Molar ratios of Mg/Mn and Ca/Mn were different among sites and showed potential as indicators of soil acidification. Significant correlations among soil, sap, foliage, and xylem wood Mn were also noted. These results show clear Mn differences among sites and, when viewed with recent Mn toxicity experiments and other observational studies, suggest that excessive Mn may play a role in the observed decline and mortality of sugar maple.


Assuntos
Acer/metabolismo , Manganês/análise , Solo/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Manganês/metabolismo , Pennsylvania , Folhas de Planta/química
4.
J Environ Health ; 68(2): 17-22, 36, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16220718

RESUMO

Pennsylvania has a large population that relies on private water wells, but no statewide regulations govern the location or construction of the wells. Bacterial contamination occurs in nearly half of these water supplies, representing a health risk to rural residents. The role of large-scale aquifer contamination versus wellhead contamination from poor construction is poorly understood. The authors disinfected and installed sanitary well caps on 16 wells that contained coliform bacteria and retested them after 30-60 days and one year. Coliform bacteria were present in seven of the 16 wells within 30-60 days and all but two wells within one year. The occurrence and prevalence of bacteria in wells appeared to be influenced by weather conditions during the study. The few wells where disinfection and installation of a sanitary well cap were successful had low initial coliform bacteria and no E. coli. Samples were also collected from 24 new wells that were constructed with a grout seal and sanitary well cap. Twenty-nine percent contained coliform bacteria, and 17 percent contained E. coli. The results from this limited number of wells suggest that bacterial contamination of private wells in Pennsylvania may often originate from areas away from the wellhead.


Assuntos
Microbiologia da Água , Abastecimento de Água , Escherichia coli/isolamento & purificação , Pennsylvania
6.
Tree Physiol ; 16(11_12): 923-932, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-14871785

RESUMO

We assessed the impacts of hay-scented fern (Dennstaedtia punctilobula (Michx.) Moore) and subsoil liming (CaO amendments) on root and shoot growth of greenhouse-grown, first-year, northern red oak (Quercus rubra L.) seedlings. Red oak seedlings and ferns were grown in reconstructed soil profiles of four common Pennsylvanian forest soils. When grown in the presence of hay-scented ferns, with or without subsoil liming, red oak seedlings had significantly reduced height growth, and foliar, stem and total root biomass. Fern foliar biomass was significantly reduced when ferns were grown with red oaks, but there was no significant difference in total belowground biomass of ferns. Belowground fern biomass was concentrated in the upper soil profile, whereas red oak roots showed a variety of distributions. In the presence of ferns, fine root branching in red oak was reduced in the organic horizons of three of the four soils tested. In both the presence and absence of ferns, root branching in red oak was also significantly and negatively correlated with the concentration of 0.01 M SrCl(2)-extractable aluminum in the mineral horizons (r(2) = 0.77). Subsoil liming generally improved root branching in red oaks. The presence of ferns significantly reduced ectomycorrhizal infection frequency in red oak. We conclude that hay-scented fern inhibited root branching and suppressed above- and belowground biomass accumulation of first-year northern red oak seedlings.

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