The illusion of environmental iodine deficiency

The distribution of endemic goitre in England and Wales was compared with the distribution of environmental iodine (atmospheric deposition, soil, surface water). Despite a very clear goitre belt through the west of England and Wales there was no patterning in the environmental iodine distribution. A clear seasonal variation in depositional iodine exists, with an unusually high concentration of iodine in March 1997. The temporal variation in iodine concentration is determined at the monthly and not the annual level. The presence of endemic goitre is no indicator of how iodine is distributed in the environment or vice versa!     

Estimating oil spill characteristics from oil heads in scattered monitoring wells

The results are presented of a comparison of four different methods of interpolating observed hydrocarbon depths in monitoring wells, as well as a comparison of different methods of selecting sampling points for interpolation. The results provide criteria for selecting one interpolation method over another, under different scenarios. The methods analyzed are: (1) inverse-distance weighting; (2) punctual kriging; (3) minimum surface curvature; and (4) Akima's quintic polynomial.     

Characterization and pilot‐scale studies for chemical oxidation remediation of fractured shale

The distribution of volatile organic compounds (VOCs) in fractured shale overlain by thin (< 10 feet) overburden at the Watervliet Arsenal near Albany, New York, was initially determined by sampling water from the fracture network using packer systems in boreholes and also using conventional monitoring wells. Furthermore, short‐term pumping and injection tests were conducted and the boreholes were logged using a variety of geophysical and hydrophysical tools. Tetrachloroethene is the dominant VOC in the groundwater, with lesser concentrations of trichloroethene and degradation products (cis‐1,2‐dichloroethene, trans‐1,2‐dichloroethene, and vinyl chloride). The vertical VOC distributions in the rock matrix were obtained from continuous‐cored holes from which small rock samples, collected at many depths between 18 and 150 feet below ground surface, were analyzed. The rock core VOC concentrations were determined by methanol extraction of crushed rock followed by direct methanol injection onto a gas chromatograph and subsequent estimation of rock porewater VOC concentrations. The rock core data support the concept that diffusion‐driven mass transfer has caused nearly all the VOC mass initially present in the fractures to now reside in the rock matrix, which has a porosity three or four orders of magnitude larger than the bulk fracture porosity. The results of the site characterization indicate that an effective site investigation strategy in fractured shale must include characterization of both the fracture and matrix contaminant distribution. These results also indicate that the most favorable remediation technologies for this fractured shale are those that will destroy VOCs in the rock matrix, particularly contaminants in the sorbed phase, and also destroy the VOC mass in the fractures including both dissolved and immiscible phases. The site characterization resulted in the selection of potassium permanganate for an in situ chemical oxidation pilot study. © 2004 Wiley Periodicals, Inc.     

Application of Sediment Quality Guidelines in the Assessment and Management of Contaminated Surficial Sediments in Port Jackson (Sydney Harbour), Australia

Sediments in the Port Jackson estuary are polluted by a wide range of toxicants and concentrations are among the highest reported for any major harbor in the world. Sediment quality guidelines (SQGs), developed by the National Oceanographic and Atmospheric Administration (NOAA) in the United States are used to estimate possible adverse biological effects of sedimentary contaminants in Port Jackson to benthic animals. The NOAA guidelines indicate that Pb, Zn, DDD, and DDE are the most likely contaminants to cause adverse biological effects in Port Jackson. On an individual chemical basis, the detrimental effects due to these toxicants may occur over extensive areas of the harbor, i.e., about 40%, 30%, 15% and 50%, respectively. The NOAA SQGs can also be used to estimate the probability of sediment toxicity for contaminant mixtures by determining the number of contaminants exceeding an upper guideline value (effects range medium, or ERM), which predicts probable adverse biological effects. The exceedence approach is used in the current study to estimate the probability of sediment toxicity and to prioritize the harbour in terms of possible adverse effects on sediment-dwelling animals. Approximately 1% of the harbor is mantled with sediment containing more than ten contaminants exceeding their respective ERM concentrations and, based on NOAA data, these sediments have an 80% probability of being toxic. Sediment with six to ten contaminants exceeding their respective ERM guidelines extend over approximately 4% of the harbor and have a 57% probability of toxicity. These areas are located in the landward reaches of embayments in the upper and central harbor in proximity to the most industrialised and urbanized part of the catchment. Sediment in a further 17% of the harbor has between one and five exceedences and has a 32% probability of being toxic. The application of SQGs developed by NOAA has not been tested outside North America, and the validity of using them in Port Jackson has yet to be demonstrated. The screening approach adopted here is to use SQGs to identify contaminants of concern and to determine areas of environmental risk. The practical application and management implications of the results of this investigation are discussed.     

Career communities: a preliminary exploration of member‐defined career support structures

This paper explores the concept of career communities: social structures that provide career support and frequently transcend the boundaries of any single organization. The theoretical background notes the convergence of a number of different perspectives from both career development and organization studies, pertaining to the social contextualization of careers. The methodology involved eliciting expressions of the (individual) subjective career from the members of three potential career communities, and then exploring (communal) inter‐subjective interpretations in focus groups. Our results suggest that career communities typically involve a hybrid of types rather than any one pure type. Preliminary support is found for the view that career communities facilitate career support, sensemaking and learning. The results invite further research into career communities and have implications for organizational behavior and human resource management, suggesting greater appreciation of the extra‐organizational as well as intra‐organizational communities in which careers develop. Copyright © 2004 John Wiley & Sons, Ltd.     

Atmospheric and kinetic studies of OH and HO2 by the FAGE technique

A new FAGE setup has recently been built at the University of Lille, France. It permits the quantification of OH and HO₂ in the atmosphere with a detection limit of 3×10⁵ molecules/(cm³·min) for OH and 1×10⁶ molecules/(cm⁵·min) for HO₂. Its coupling to a photolysis cell enables the measurement of the total reactivity of the hydroxyl radical in ambient air and kinetic studies in laboratory. Two configurations have been considered: one with the photolysis cell at 90° to the FAGE nozzle, the other on line with the FAGE nozzle. The two configurations have been tested and validated by measuring the well known rate constants of OH with CH₄, C₃H₈ and CO. The advantages and drawbacks of each configuration have been evaluated. The “on line” configuration limits losses and permits measurements over a larger reactivity range but is affected by OH formation from the laser beam striking the FAGE nozzle, thus limiting the ability to carry out energy dependence studies which can, in contrast, be successfully performed in the 90° configuration.     

Detecting Insect Pollinator Declines on Regional and Global Scales

Recently there has been considerable concern about declines in bee communities in agricultural and natural habitats. The value of pollination to agriculture, provided primarily by bees, is >$200 billion/year worldwide, and in natural ecosystems it is thought to be even greater. However, no monitoring program exists to accurately detect declines in abundance of insect pollinators; thus, it is difficult to quantify the status of bee communities or estimate the extent of declines. We used data from 11 multiyear studies of bee communities to devise a program to monitor pollinators at regional, national, or international scales. In these studies, 7 different methods for sampling bees were used and bees were sampled on 3 different continents. We estimated that a monitoring program with 200–250 sampling locations each sampled twice over 5 years would provide sufficient power to detect small (2–5%) annual declines in the number of species and in total abundance and would cost U.S.$2,000,000. To detect declines as small as 1% annually over the same period would require >300 sampling locations. Given the role of pollinators in food security and ecosystem function, we recommend establishment of integrated regional and international monitoring programs to detect changes in pollinator communities. Detección de Declinaciones de Insectos Polinizadores a Escalas Regional y Global     

An analytical design technique for magnetic field therapy devices

Electromagnetic therapy devices designed over the last 45 years have been based on empirical (trial-and-error) techniques. This paper presents a novel approach to designing and engineering therapeutic devices. Based upon using a superconductive quantum interference device (SQUID) magnetometer for registration of the magnetic field emitted by specific organs in norm and after the injury/pathology, this approach avoids empirical engineering. The signal parameters recorded by the SQUID magnetometer allow one to derive tissue- and/or disease-specific signals. This is made possible using contemporary, state-of-the-art controls with engineering and computer science techniques.