Are all chromosome microarrays the same? What clinicians need to know

Microarray testing is the recommended first-tier diagnostic test for women who undergo invasive prenatal diagnostic procedures. It is well-established that microarray analysis provides information regarding copy number for changes (or copy number variants, CNVs) that may be below the resolution level of standard chromosome analysis, and that such CNVs are not related to maternal age. What may not be appreciated by ordering providers, however, are the technical differences among laboratories with respect to the established laboratory cutoff values for reporting, the definition of targeted versus nontargeted regions, and how these differences may affect the interpretation and reporting of findings which, in turn, affects counseling and possible follow-up testing of family members. Here, we provide a detailed explanation of these technical factors and clarify how they practically impact diagnostic results.     

Environmental performance and practice across sectors: methodology and preliminary results

This paper introduces a new methodology for measuring and modeling manufacturers’ environmental performance and the managerial and technological practices that affect it. Facility level licensing data are used to develop indicators based on sector-specific criteria but capable of being analyzed across sectors, at various levels of aggregation. This addresses the problem that environmental performance and determinants tend to be highly context-specific, while modeling and policy interests are often more general. Using Integrated Pollution Control (IPC) information generated EU-wide, this approach should be capable of cross-country extension. The methodology is tested on a sample of Irish facilities in three sectors during 1996–2004. Preliminary results show its usefulness in exploring the determinants of environmental performance at the sector and cross sector levels. Word count = 10,049.     

Parasitism and a shortage of refuges jointly mediate the strength of density dependence in a reef fish

Various predator-prey, host-pathogen, and competitive interactions can combine to cause density dependence in population growth. Despite this possibility, most empirical tests for density-dependent interactions have focused on single mechanisms. Here we tested the hypothesis that two mechanisms of density dependence, parasitism and a shortage of refuges, jointly influence the strength of density-dependent mortality. We used mark-recapture analysis to estimate mortality of the host species, the bridled goby (Coryphopterus glaucofraenum). Sixty-three marked gobies were infected with a copepod gill parasite (Pharodes tortugensis), and 188 were uninfected. We used the spatial scale at which gobies were clustered naturally (approximately 4 m2) as an ecologically relevant neighborhood and measured goby density and the availability of refuges from predators within each goby's neighborhood. Goby survival generally declined with increasing density, and this decline was steeper for gobies with access to few refuges than for gobies in neighborhoods where refuges were common. The negative effects of high density and refuge shortage were also more severe for parasitized gobies than for gobies free of parasites. This parasite has characteristics typical of emerging diseases and appears to have altered the strength of a preexisting density-dependent interaction.     

Initial investigation on the use of waterjets to place amendments in the subsurface

Quasi‐passive in situ remediation technologies, such as the use of permeable reactive barriers to treat contaminated groundwater or applications of granular activated carbon to treat polychlorinated biphenyl (PCB)‐contaminated, near‐surface sediments, are proven or promising technologies that may be limited in application due to the traditional construction techniques normally used for placement in the environment. High‐pressure waterjets have traditionally been used to excavate material during mining operations or to cut rock or other durable material. Waterjets have the potential to place amendments in the subsurface at depths greater than those that can be obtained using traditional construction techniques. Likewise, waterjets may have less negative impact on near‐surface utilities and/or sensitive ecological systems. Laboratory experiments were performed to characterize the placement of two solid amendments in a simulated saturated aquifer. A second set of experiments was performed to characterize the effectiveness of waterjets for placing a third amendment in simulated intertidal sediments. The laboratory work focused on characterizing the nature of the waterjet penetration of the aquifer matrix and the saturated sediments, as well as the corresponding waterjet parameters of pressure, nozzle size, and injection time. The laboratory results suggest that field trials may be appropriate for future investigations. © 2005 Wiley Periodicals, Inc.     

Integrated Assessment of Abatement Strategies to Improve Air Quality in Urban Environments, the USIAM Model

Planning effective strategies to combat air pollution in amajor city such as London requires integration ofinformation on atmospheric concentrations and where theyexceed prescribed air quality standards, detailed data onemissions and potential measures to reduce them includingcosts, and a good understanding of the relativecontributions of different emission sources to pollutantconcentrations plus the remaining background. The UrbanScale Integrated Assessment Model (USIAM) is designed as atool to integrate such information, and to explore andassess a variety of potential strategies for improving airquality. It is based on the same principles as theAbatement Strategies Assessment Model (ASAM) that has beenused in the UN Economic Commission for Europe. To startwith the USIAM model is being developed with respect to theparticulate PM₁₀ only, and in particular the primaryparticulate contribution. The secondary particulate istreated as part of the background superimposed on theprimary particulate concentrations; this may need to betreated more specifically at a later stage, particularlywith respect to nitrate formation over the city. The USIAMmodel therefore sets out to examine a selection of severeepisode conditions as well as long-term annual averageconcentrations, and aims to find strategies that aresuccessful in eliminating exceedance of the prescribedtarget concentrations. By ranking different options forabatement of emissions, for example in terms of cost orease of implementation, the USIAM model can also select andprioritise different potential strategies.     

USING TECHNICAL ADAPTIVE MANAGEMENT TO IMPROVE DESIGN GUIDELINES FOR URBAN INSTREAM STRUCTURES1

ABSTRACT: Adaptive management is a heuristic approach to treating stream restoration projects as continuous, cyclic experiments, yielding results to be incorporated into future decisions. This comprehensive assessment views failures as surprises that are valuable lessons. Monitoring, evaluation of data, and communication of results are critical; the monitoring results trigger feedback mechanisms to invoke adaptation to the newly acquired information and communication of new hypotheses, treatments, or policies. The principles of adaptive management were applied to a monitoring study of three urban stream restoration sites in Maryland. Data were collected and evaluated for various restoration techniques, including vanes, cross vanes, step pools, root wads, imbricated riprap walls, and coir fiber rolls. Improvements to the existing Maryland design guidelines and policies were developed as the feedback mechanism. With the increasing application of adaptive management in stream restoration efforts, it is likely that repeated failures will be prevented and future restoration projects will be more successful in achieving their goals.     

Kin discrimination in the spotted hyena (<Emphasis Type="Italic">Crocuta crocuta</Emphasis>): nepotism among siblings

We examined patterns of affiliation, association, and aggression to inquire whether spotted hyenas (Crocuta crocuta) can distinguish among various groups of maternal and paternal siblings. If so, and if these animals conform to predictions of kin selection theory, then behavioral interactions among hyenas should vary with relatedness. We also considered familiarity-based recognition and phenotype matching as mechanisms hyenas might use to recognize kin. Patterns of affiliative behavior indicated that hyenas favored full-sibling littermates over half-sibling littermates or any other group of half-siblings. Rates of dyadic aggression generally did not vary with kinship. Hyenas associated more closely with half-sibling littermates than with non-littermate half-siblings, and hyenas affiliated more with maternal half-siblings than with paternal half-siblings, suggesting that familiarity-based cues might mediate discrimination among these sibling classes. In addition, operation of a phenotype-matching mechanism was suggested by the preference hyenas demonstrated during affiliative interactions for full- over half-sibling littermates, and by their lack of preference in these interactions for half-sibling littermates over non-littermate half-siblings. Phenotype matching was also suggested by our observation that paternal half-siblings cooperated more, and fought less, than did non-kin. Our data indicate that hyenas can discriminate among various types of siblings, that their social behavior conforms to predictions of kin selection theory, and that they recognize kin using mechanisms of both familiarity and phenotype matching.Communicated by S. Alberts