Characterizing a Major Urban Stream Restoration Project: Nine Mile Run (Pittsburgh,Pennsylvania, USA)

Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long‐term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi‐million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post‐project assessment should include examination of a wider range of indicators.     

Risk-based standards: integrating top–down and bottom–up approaches

In response to rapidly changing threats posed to increasingly complex socio-technical systems, many in the government and private sector have called for protection through risk-based standards. However, given the nature of these dynamic and uncertain threats, traditional risk assessment techniques may not be sufficient. Instead, there is a critical need for an integrated approach in which decision analytic techniques are used to assess evidence-based data with the values and preferences of decision makers. We point to three examples in the fields of nuclear power regulation, nanotechnology, and cybersecurity, where risk-based approaches (bottom–up) have been combined with decision analysis (top–down) to guide decision makers toward risk management policies that manifest both the best available evidence and the plurality of values within a society.     

Ripping Improves Tree Survival and Growth on Unused Reclaimed Mined Lands

There is renewed interest in re-establishing trees on 0.6 million ha of mining-disturbed lands in the Appalachian mountains of Eastern United States. Many coal-mined lands reclaimed to meet requirements of US federal law have thick herbaceous vegetation and compacted soils which impede tree establishment. Mitigation practices were applied on three mine sites and evaluated for success in enabling planted trees to become established. Eastern white pine (Pinus strobus), hybrid poplar (Populus deltoids × Populus trichocarpa), and mixed Appalachian hardwoods were established using weed control only and weed control with subsoil ripping. Trees were measured in October of 2008 after 5 years of growth. Subsoil ripping increased mixed hardwood survival from 43 to 71 %, hybrid poplar biomass index from 1.51 to 8.97 Mg ha^?1, and Eastern white pine biomass index from 0.10 to 0.32 Mg ha^?1. When restoring trees to unused mined sites, subsoil ripping can aid survival and growth to an extent that will result in a valuable forest.     

Accounting for time in Mitigating Global Warming through land-use change and forestry

Many proposed activities formitigating global warming in the land-use change and forestry(LUCF) sector differ from measures to avoid fossilfuel emissions because carbon (C) may be held out ofthe atmosphere only temporarily. In addition, thetiming of the effects is usually different. Many LUCFactivities alter C fluxes to and from the atmosphereseveral decades into the future, whereas fossil fuelemissions avoidance has immediate effects. Non-CO₂ greenhouse gases (GHGs), which are animportant part of emissions from deforestation inlow-latitude regions, also pose complications forcomparisons between fossil fuel and LUCF, since themechanism generally used to compare these gases(global warming potentials) assumes simultaneousemissions. A common numeraire is needed to expressglobal warming mitigation benefits of different kindsof projects, such as fossil fuel emissions reduction,C sequestration in forest plantations, avoideddeforestation by creating protected areas and throughpolicy changes to slow rates of land-use changes suchas clearing. Megagram (Mg)-year (also known as`ton-year') accounting provides a mechanism forexpressing the benefits of activities such as these ona consistent basis. One can calculate the atmosphericload of each GHG that will be present in each year,expressed as C in the form of CO₂ and itsinstantaneous impact equivalent contributed by othergases. The atmospheric load of CO₂-equivalent Cpresent over a time horizon is a possible indicator ofthe climatic impact of the emission that placed thisload in the atmosphere. Conversely, this index alsoprovides a measure of the benefit of notproducing the emission. One accounting methodcompares sequestered CO₂ in trees with theCO₂ that would be in the atmosphere had thesequestration project not been undertaken, whileanother method (used in this paper) compares theatmospheric load of C (or equivalent in non-CO₂GHGs) in both project and no-project scenarios.Time preference, expressed by means of a discount rateon C, can be applied to Mg-year equivalencecalculations to allow societal decisions regarding thevalue of time to be integrated into the system forcalculating global warming impacts and benefits. Giving a high value to time, either by raising thediscount rate or by shortening the time horizon,increases the value attributed to temporarysequestration (such as many forest plantationprojects). A high value for time also favorsmitigation measures that have rapid effects (such asslowing deforestation rates) as compared to measuresthat only affect emissions years in the future (suchas creating protected areas in countries with largeareas of remaining forest). Decisions on temporalissues will guide mitigation efforts towards optionsthat may or may not be desirable on the basis ofsocial and environmental effects in spheres other thanglobal warming. How sustainable development criteriaare incorporated into the approval and creditingsystems for activities under the Kyoto Protocol willdetermine the overall environmental and social impactsof pending decisions on temporal issues.     

Prenatal diagnosis of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency by steroid analysis in the amniotic fluid of mid-pregnancy: Comparison with HLA typing in 17 pregnancies at risk for CAH

Amniotic fluid (AF) levels of 17-hydroxyprogesterone (17OHP) and testosterone (T) were determined at 16–17 weeks in 17 pregnancies at risk for CAH and results compared to 75 normal controls. The fetus was predicted to be unaffected in 12 cases on the findings of normal AF levels of both 17OHP and T and the latter allowed a correct prediction of fetal sex in all instances. HLA typing confirmed normality in 12 cases revealing 5 carriers, 5 homozygous normal and 2 indeterminate. Steroid levels of the 2 groups were similar. Three fetuses were predicted to be CAH affected on unambiguously high levels of 17OHP and T (in female only). HLA typing was in agreement, and the diagnosis was confirmed in 2 abortuses and a female newborn by physical and hormonal studies. In the last 2 cases AF levels of OHP and T were normal but HLA (A/B/C) genotypes were identical to the CAH affected siblings. Normal physical and hormonal findings in the 2 aborted fetuses would exclude the possibility of an in utero virilizing form of CAH. The discrepancy could be explained on the basis that the fetuses had an allelic form of 21-hydroxylase deficiency or on the basis of recombination (not fully tested). It is concluded that a fully informative prenatal diagnosis of CAH should not rely entirely on HLA typing but on hormonal studies.     

Hypoxia in the Baltic Sea: Biogeochemical Cycles, Benthic Fauna, and Management

Hypoxia has occurred intermittently over the Holocene in the Baltic Sea, but the recent expansion from less than 10 000 km² before 1950 to >60 000 km² since 2000 is mainly caused by enhanced nutrient inputs from land and atmosphere. With worsening hypoxia, the role of sediments changes from nitrogen removal to nitrogen release as ammonium. At present, denitrification in the water column and sediments is equally important. Phosphorus is currently buried in sediments mainly in organic form, with an additional contribution of reduced Fe-phosphate minerals in the deep anoxic basins. Upon the transition to oxic conditions, a significant proportion of the organic phosphorus will be remineralized, with the phosphorus then being bound to iron oxides. This iron-oxide bound phosphorus is readily released to the water column upon the onset of hypoxia again. Important ecosystems services carried out by the benthic fauna, including biogeochemical feedback-loops and biomass production, are also lost with hypoxia. The results provide quantitative knowledge of nutrient release and recycling processes under various environmental conditions in support of decision support tools underlying the Baltic Sea Action Plan.     

Cytogenetic biomonitoring of oral mucosa cells of crack cocaine users

The aim of the present study was to comparatively evaluate genomic damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated oral mucosa cells from crack cocaine users by micronucleus test. A total of 30 crack cocaine users and 30 health controls (non-exposed individuals) were included in this setting. Individuals had epithelial cells from cheek mechanically exfoliated, placed in fixative, and dropped in clean slides, which were checked for the above nuclear phenotypes. The results pointed out significant statistical differences (p?<?0.05) of micronucleated oral mucosa cells from crack cocaine users. Exposure to crack cocaine caused an increase of other nuclear alterations closely related to cytotoxicity such as karyolysis in oral cells as well. In summary, these data indicate that crack cocaine is able to induce chromosomal breakage and cellular death in oral mucosa cells of users.     

Interlaboratory evaluation of endotoxin analyses in agricultural dusts--comparison of LAL assay and mass spectrometry

Endotoxin exposure is associated with wheeze and asthma morbidity, while early life exposure may reduce risk of allergy and asthma. Unfortunately, it is difficult to compare endotoxin results from different laboratories and environments. We undertook this study to determine if lipopolysaccharide (LPS) extraction efficiency could account for differences among laboratories. We generated and collected aerosols from chicken and swine barns, and corn processing. We randomly allocated side-by-side filter samples to five laboratories for Limulus assay of endotoxin. Lyophilized aliquots of filter extracts were analyzed for 3-hydroxy fatty acids (3-OHFAs) as a marker of LPS using gas chromatography-mass spectrometry. There were significant differences in endotoxin assay and GC-MS (LPS) results between laboratories for all dust types (p < 0.01). Patterns of differences between labs varied by dust type. Relationships between assay and GC/MS results also depended on dust type. The percentages of individual 3-OHFA chain lengths varied across labs (p < 0.0001) suggesting that each lab recovered a different fraction of the LPS available. The presence of large amounts of particle associated LPS and absence of a freezing thawing cycle were associated with lower correlations between LPS and bioactivity, consistent with an absence of Limulus response to cell-bound endotoxin. These data suggest that extraction methods affect endotoxin measurements. The LAL methods may be most suitable when comparing exposures within similar environments; GC-MS offers additional information helpful in optimizing sample treatment and extraction. GC-MS may be of use when comparing across heterogeneous environments and should be considered for inclusion in future studies of human health outcomes.     

Copper distribution in surface and subsurface soil horizons

The horizons of four natural soils were treated with Cu²⁺ in an acid medium to study the retention capacity of Cu. The possible mineralogical changes arising because of the treatment were also studied. The soil properties and characteristics with the greatest influence on the metal retention and its distribution among the different soil fractions were determined. Crystalline phases of each horizon were determined by X-ray diffraction (XDR). The morphology, structural distribution and particle chemical composition of soil samples were investigated using field emission scanning electron microscopy. Cu distribution in the different geochemical phases of the soil was studied using a sequential extraction. The treatment led to an increase in the amorphous phases and the formation of new crystalline phases, such as rouaite (Cu₂(NO₃)(OH)₃) and nitratine (NaNO₃). Cu was also found superficially sorbed on amorphous hydroxy compounds of Fe that interact with albite, muscovite and gibbsite, and also on spherical and curved particles of aluminium clays. The largest amount of Cu retained was in an exchangeable form, and the smallest amount associated with the crystalline Fe oxides and residual fraction. In the surface horizons, the predominant Cu retention process is complexation in organomineral associations, while in the subsurface horizons it is adsorption.     

Improved speciation of dissolved organic nitrogen in natural waters: amide hydrolysis with fluorescence derivatization

The objective of this study was to improve primary-amine nitrogen (1°-N) quantification in dissolved organic matter (DOM) originating from natural waters where inorganic forms of N, which may cause analytical interference, are commonly encountered. Efforts were targeted at elucidating organic-N structural criteria influencing the response of organic amines to known colorimetric and fluorescent reagents and exploring the use of divalent metal-assisted amide hydrolysis in combination with fluorescence analyse...