Cation transport by bone marrow cells from vitamin-E-deficient mice

This work was supported financially by the ministry of the Interior at Bonn. The authors wish to acknowledge the valuable and skillful technical assistance of W. Steffens and E. Bardon.     

Who's on the greenway: Socioeconomic,demographic, and locational characteristics of greenway users

In response to continued public concern sparked by the loss of open space and greenbelts around American cities, greenways have gained nationwide popularity as a land conservation strategy. This study examines the socioeconomic, demographic, and locational characteristics of greenway users. Three hundred twenty users on four trails of the Capital Area Greenway System in Raleigh, North Carolina, were surveyed. The Raleigh system is extensive, providing 43.7 km (27 mi) of trails, thus allowing examination of greenway use in a variety of settings. The survey findings indicated that most patrons were drawn from within an 8.05-km (5-mi) radius of the greenway. The typical Capital Area Greenway user is a white female between the age of 16 and 34 with no children. Socioeconomically, greenway users are employed, well-educated, and have above average incomes. A disproportionate share of greenway visitors belong to an environmental group.     

The big clean up: social marketing for the Auckland region

The Big Clean Up (BCU) started in 2001 as Auckland Regional Council's (ARC) sustainability social marketing project and arose from catalysts for change that occurred within ARC in the late 1990s—leadership, training, partnerships and values. The BCU features strong marketing images and messages that have increased awareness and participation in the region according to extensive stakeholder surveys. It is intended to engage individuals and households in sustainable living—especially among the public middle ground—not those already committed to a green lifestyle. Membership of BCU after one year is about 44,000—almost one in ten households. Although ARC has considered the BCU successful, questions arise about the level of resilience of the campaigns without ongoing investment in expensive multimedia advertising and other initiatives. The paper concludes with a discussion on the impact of the underlying pedagogy in the light of social marketing and behaviour change theory.     

An evaluation of the bioavailability and bioaccumulation of selected metals occurring in a wetland area on the volcanic island of Guam, Western Pacific Ocean

This initial research examined the presence, distribution and bioavailability of Cu, Cr, Ni, Mn and Fe in a wetland area of southern Guam. The research sites are within an area covered with saporite, a soil type derived from volcanic deposits on the island. Leaf tissue of Pandanus tectorius was extracted and analysed to determine the bioaccumulation of the target metals. Metal accumulation at sites considered aerobic and anaerobic was investigated together with an attempt to correlate actual accumulation of the target metals in the plant tissue with a recognised bioavailability indicator, in this case, three step sequential extraction scheme. Manganese was found to be accumulated in relatively high concentrations and to a lesser extent Cu was also accumulated. Chromium, Ni and Fe however exhibited very low accumulation factors. Accumulation of Mn in particular was significantly a ected by aerobic conditions whereas the converse e ect was experienced by Cu. Significant correlation between various steps of a Sequential Extraction Scheme and actual accumulation was not achieved although the degree of aerobic conditions at each site and soil pH did a ect concentrations of metals extracted by di ering steps of SES. Results obtained suggest that further research in the area should be undertaken using di erent plant species and tissues.     

Where clocks are redundant: weak circadian mechanisms in reindeer living under polar photic conditions

Biological rhythms are a result of interplay between endogenous clocks and the ambient light–dark (LD) cycle. Biological timing in resident polar organisms presents a conundrum because these experience distinct daily LD cycles for only a few weeks each year. We measured locomotor activity in reindeer, Rangifer tarandus platyrhynchus (SR, n = 5 and 6) and R. tarandus tarandus (NR, n = 6), ranging freely at 78 and 70°N, respectively, continuously throughout 1 year using data loggers. NR, but not SR, are gregarious which enabled us to examine the integrated effects of differences in social organisation and the photic environment at two different latitudes on the organisation of activity. In both sub-species, ultradian bouts of activity and inactivity alternated across the 24-h day throughout the year. This pattern was modified by the LD cycle in NR but barely at all in SR. Periodogram analysis revealed significant ultradian rhythmicity in both sub-species; the frequency of daily cycles of activity increased from three per day in winter to nearly five in summer. We conclude that this increase, and a concomitant increase in the level of daily activity, reflected the seasonal increase in the animals’ appetite and the quality of their forage. Secondly, the combination, most evident in SR, of a weak photic response, weak circadian mechanisms and a weak social synchronization reduces the constraints of biological timing in an environment which is effectively non-rhythmic most of the year and permits expression of the basic ultradian pattern of ruminant activity. Third, the weaker 24-h rhythmicity in SR compared to NR indicates a latitudinal decrease in circadian organization and photic responsiveness in Rangifer.     

Forest to reclaimed mine land use change leads to altered ecosystem structure and function.

The United States' use of coal results in many environmental alterations. In the Appalachian coal belt region, one widespread alteration is conversion of forest to reclaimed mineland. The goal of this study was to quantify the changes to ecosystem structure and function associated with a conversion from forest to reclaimed mine grassland by comparing a small watershed containing a 15-year-old reclaimed mine with a forested, reference watershed in western Maryland. Major differences were apparent between the two watersheds in terms of biogeochemistry. Total C, N, and P pools were all substantially lower at the mined site, mainly due to the removal of woody biomass but also, in the case of P, to reductions in soil pools. Mineral soil C, N, and P pools were 96%, 79%, and 69% of native soils, respectively. Although annual runoff from the watersheds was similar, the mined watershed exhibited taller, narrower storm peaks as a result of a higher soil bulk density and decreased infiltration rates. Stream export of N was much lower in the mined watershed due to lower net nitrification rates and nitrate concentrations in soil. However, stream export of sediment and P and summer stream temperature were much higher. Stream leaf decomposition was reduced and macroinvertebrate community structure was altered as a result of these changes to the stream environment. This land use change leads to substantial, long-term changes in ecosystem capital and function.     

Remote estimation of phycocyanin (PC) for inland waters coupled with YSI PC fluorescence probe

Nuisance cyanobacterial blooms degrade water resources through accelerated eutrophication, odor generation, and production of toxins that cause adverse effects on human health. Quick and effective methods for detecting cyanobacterial abundance in drinking water supplies are urgently needed to compliment conventional laboratory methods, which are costly and time consuming. Hyperspectral remote sensing can be an effective approach for rapid assessment of cyanobacterial blooms. Samples (n?=?250) were collected from five drinking water sources in central Indiana (CIN), USA, and South Australia (SA), which experience nuisance cyanobacterial blooms. In situ hyperspectral data were used to develop models by relating spectral signal with handheld fluorescence probe (YSI 6600 XLM-SV) measured phycocyanin (PC in cell/ml), a proxy pigment unique for indicating the presence of cyanobacteria. Three-band model (TBM), which is effective for chlorophyll-a estimates, was tuned to quantify cyanobacteria coupled with the PC probe measured cyanobacteria. As a comparison, two band model proposed by Simis et al. (Limnol Oceanogr, 50(11): 237–245, 2005; denoted as SM05) was paralleled to evaluate TBM model performance. Our observation revealed a high correlation between measured and estimated PC for SA dataset (R ²?=?0.96; range: 534–20,200 cell/ml) and CIN dataset (R ²?=?0.88; range: 1,300–44,500 cell/ml). The potential of this modeling approach for imagery data were assessed by simulated ESA/Centinel3/OLCI spectra, which also resulted in satisfactory performance with the TBM for both SA dataset (RMSE %?=?26.12) and CIN dataset (RMSE %?=?34.49). Close relationship between probe-measured PC and laboratory measured cyanobacteria biovolume was observed (R ²?=?0.93, p?<?0.0001) for the CIN dataset, indicating a stable performance for PC probe. Based on our observation, field spectroscopic measurement coupled with PC probe measurements can provide quantitative cyanobacterial bloom information from both relatively static and flowing inland waters. Hence, it has promising implications for water resource managers to obtain information for early warning detection of cyanobacterial blooms through the close association between probe measured PC values and cyanobacterial biovolume via remote sensing modeling.     

Improvement of Hot–side Precipitator Performance with Sodium Conditioning—An Interim Report

The development of an unexpected, time-dependent degradation of performance of hot-side precipitators collecting ash from certain coals (usually low-sodium, low-sulfur coals) has caused serious problems at a number of major utility installations. A jointly funded research project was developed under the sponsorship of the U.S. Environmental Protection Agency, the Electric Power Research Institute, and Southern Company Services, Inc., to evaluate sodium conditioning as a possible solution to these performance deficiency problems.