Editorial: Statistical ecology and forest biometry

Environmental and Ecological Statistics -     

First trimester diagnosis of lesch-nyhan syndrome: Applications to other disorders of purine metabolism

The prenatal detection of hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8) deficiency, the Lesch-Nyhan syndrome, during the first trimester of an affected pregnancy through the use of chorionic villus sampling is reported. Quantitation of reaction products formed by villus cell extracts from exogenous hypoxanthine-8-[¹⁴C] or adenine-8-[¹⁴C] is used in diagnosis. We report the diagnosis of Lesch-Nyhan syndrome using a chorionic villus specimen and confirmation of that diagnosis. In addition, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), enzymes deficient in inherited immune disorders, are detected in chorionic villus samples. These heritable disorders also appear amenable to early prenatal diagnosis.     

Effect of Harvest on Leaf Development of the Asian Palm Livistona rotundifolia

Although palms are the most commonly harvested tree family in the world, they are susceptible to overexploitation, and many harvest schemes are not sustainable. We assessed the impact of leaf harvesting of the Asian palm, Livistona rotundifolia , in North Sulawesi, Indonesia, to determine the effect of harvest intensity on subsequent growth and to determine if current harvest practices are ecologically sustainable. We conducted experimental harvests of two intensities and compared results with a control. Leaf emergence, expansion, opening, and maturation were monitored for 1 year. Leaves in heavy and light harvest treatments grew and opened significantly faster than control leaves. Final leaf size was a function of harvest intensity: control leaves were larger (4.06 m) than light-harvest leaves (3.62 m) and heavy-harvest leaves (2.62 m). Census results for palms in harvested and unharvested areas indicated that palm density was twice as high and reproductive-sized palms were 10 times more common in the unharvested area. We judged current harvest practices to be nonsustainable. Recommendations for sustainable harvesting include reduction of harvest intensity and waste and preservation of reproductive-sized palms.     

Use of extant kinetic parameters to predict effluent concentrations of specific organic compounds at full-scale facilities.

To use the results of kinetic tests to predict effluent concentrations of specific contaminants in activated sludge systems, the fraction of the biomass that has an ability to degrade the test compound (i.e., competent biomass) must be estimated. A calibration procedure was developed to assess the competent biomass concentration because the chemical oxygen demand (COD) fraction tended to underestimate the degrading fraction for three of the four test compounds. Acetone, for instance, had a measured influent COD fraction of 0.08%, and the actual competent fraction was estimated to be 2.3%, based on the model calibration. Once the competent biomass fraction in the mixed liquor was determined, the extant kinetic parameters were subsequently used to predict activated sludge system performance. Predicted effluent concentrations were within 2, 5, and 16% of the average measured concentrations for acetone, linear alkylbenzene sulfonate, and furfural, respectively. Day-to-day predictions for these compounds were less accurate, possibly because of the non-steady-state nature of the activated sludge systems studied. The difference between the fraction of the influent COD contributed by the target compounds and the competent biomass fraction in the mixed liquor was found to be more significant when the target compound contributed less than 1% of the influent organic matter. The chemical structure of the target compound and chemical composition of the influent likely had an effect on the resulting competent biomass concentration. The total maximum growth rate, microX, was observed to be independent of the influent concentration of acetone and furfural, thus suggesting that the competent biomass concentration for these compounds was not affected by the changes in their influent concentrations. Consequently, a majority of competent biomass growth resulted from the degradation of other substrates, resulting in a competent biomass concentration significantly higher than predicted based on the influent COD fraction contributed by the test compound.     

Treatability of nonylphenol ethoxylate surfactants in on-site wastewater disposal systems.

The fate of nine-mole nonylphenol ethoxylate (NPE9) discharged to an on-site wastewater disposal (septic) system was the focus of a 2-year investigation. Known amounts of NPE9-based detergent were metered daily into the plumbing at a single-family household. The ethoxylate-containing wastewater was discharged to the highly anoxic environment of a 4500-L septic tank before distribution to the oxic subsurface via 100 m of leach line. After 180 days of injecting detergent to the septic system, periodic soil pore water and/or groundwater samples were collected and analyzed for nonylphenol ethoxylates (NPEs), nonylphenol ether carboxylates, and nonylphenol. The NPE9 and degradation intermediates that were measured were reduced by 99.99% on a molar basis. An 18% reduction in molar concentration within the septic tank was observed. This was followed by a further 96.7% reduction of molar concentration within the leach lines. As the pore water migrated through the vadose zone, an additional 99.69% reduction in molar concentration was measured between the bottom of the leach lines (leach line effluent) and the lowest vadose zone monitoring location. The results obtained from these analyses indicate that degradation of the surfactant occurs within the anoxic portion of the disposal system with continued rapid biodegradation in the oxic unsaturated zone. Only trace amounts of degradation residuals were detected in soil pore water. The concentration and distribution of various degradation intermediates with respect to location, time, and ambient physical conditions were evaluated. Rapid and systematic degradation of NPE in on-site wastewater disposal systems was documented.     

The relationship between environmental management strategies and environmental compliance at Marine Corps installations

Environmental compliance requirements periodically impact the military's ability to use all installation resources. In response, environmental management strategies have been developed to ensure compliance and allow site closure. This study examines the relationship between environmental management strategies and environmental compliance at U.S. Marine Corps (USMC) installations via analysis of environmental compliance audit scores. Five environmental scores of interest from 1998 to 2004 audits—which include total compliance, total management, audit management, policy management, and training management—were subjected to statistical analysis. Results showed the USMC met environmental compliance and management standards, despite limited resources. High management strategy scores were moderately correlated with high total compliance scores. Total management scores improved over time, and noncompliance was most often associated with a lack of resources and plans. © 2006 Wiley Periodicals, Inc.     

Influence tactics and work outcomes: a meta‐analysis

Recent research on influence tactics has focused on the benefits that accrue as a result of using such tactics. The current study utilizes meta‐analytic techniques to estimate the true population correlations between various influence tactics and work‐related outcomes. Results indicate that ingratiation and rationality have positive effects on work outcomes. Additional analyses suggest that these and other influence tactics have significant effects in certain situations and on specific work outcomes. Copyright © 2003 John Wiley & Sons, Ltd.