A user-based method for rating street trees

Responses to questionnaires completed by 1,174 householders who rated characteristics of their street trees were subjected to factor analysis. The most important factors were general benefits, ground disturbance, disease, safety, seasonal marking, droppings and suckers, which became the basis for scales on which each species could be scored. These scales represent an economical and coherent method which can complement simulation and expert rating systems, for describing householder opinion towards street trees.     

Laboratory Study on Dispersant Effectiveness in Alaskan Seawater

The objective of this project was to test dispersant effectiveness in the laboratory under conditions relevant to Prince William Sound (PWS), Alaska. Two laboratory testing methods were used to compare a range of test conditions and dispersant to oil ratios (DORs) using PWS seawater at 8°C, Alaska North Slope (ANS) crude oil, and Corexit 9500. Three DORs were tested, 1:10, 1:20, and 1:50. It was found that in most cases, the dispersant effectiveness was directly proportional to the DOR. For each DOR, dispersant effectiveness was measured at four contact times (time between dispersant application to a spill and start of mixing) and five weathering times (time between oil spill and dispersant application). Corexit 9500 dispersed ANS crude oil at 8°C in PWS seawater to differing degrees, depending on the test conditions. The results indicated that, in general, the greatest dispersion occurred when the weathering time was minimized and a short contact time was provided.     

Importance of having a female cotherapist in a child molesters' group.

Including a female cotherapist in a group of child molesters can assist in generating valuable transference issues, as well as modeling appropriate social interactions between men and women. The benefits and frustrations of being a female cotherapist in a group of child molesters are examined. The significance of the interaction between the male and female cotherapists is discussed. Case examples are used to illustrate these points. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Supercritical fluid chromatographic analysis of fish oils

Various natural and processed fish oil triglyceride mixtures have been analyzed by capillary supercritical fluid chromatography (SFC). The analyses were performed on nonpolar columns to separate the components by lipid class and by the number of carbon atoms. The compounds separated included free fatty acids, squalene, α-tocopherol, cholesterol, wax esters, cholesteryl esters, di- and triglycerides. This kind of analysis is not possible by gas chromatography or high-performance liquid chromatography methods without prior treatment of the fish oil, making SFC superior for this application. Applications of SFC to fish oils are given, including a control analysis of the various process steps in the refining of a fish oil, analysis of a lipase-catalyzed transesterification of a fish oil and the detection of polymeric artifacts.     

Interaction between grounding pads used for RF ablation therapy and magnetic resonance imaging

Objectives: To characterize artifacts and imaging problems in the presence of conductive grounding pads for RF ablation therapy as well as potential heating problems due to induction of eddy currents in the pads. Strategies for avoidance of those problems are developed. Materials and methods: Underlying principles of interactions between grounding pads and MR imaging are reported. Influential parameters, e.g., orientation in relation to the magnetic field, shape of the grounding pad, sequence type (spin-echo versus gradient echo) and magnetic field strength (0.2 T, 1.5 T, 3 T) were varied in systematic phantom studies. Heating effects due to induced eddy currents were estimated theoretically and measured by infrared imaging in an adapted set-up. Results: MR imaging artifacts are markedly dependent on the orientation and geometrical shape of the grounding pads. Visible signal extinction artifacts were more pronounced using spin-echo techniques than in gradient echo images and increased for higher field strengths. Suitable incisions in the grounding pad reduced eddy currents markedly and minimized image artifacts. Heating problems due to induced eddy currents by the RF transmitted for MR imaging were excluded by phantom measurements. Conclusions: Suitable positioning of the grounding pads and adaptation of their geometry provide clearly reduced artifacts in MR imaging.     

Treatment of spent metalworking fluids

Metalworking fluids (MWFs) are widely used for cooling and lubricating during the machining process. The worldwide annual usage is estimated to exceed 2 x 10(9)l and the waste could be more than ten times the usage, as the MWFs have to be diluted prior to use. For UK industry the disposal cost is estimated to be up to pound16 million per year. Used MWFs cause high levels of contamination and rancid odours due to the presence of complex chemicals, biocides, etc., so that their treatment and final disposal must be handled carefully. Conventionally this has been done by combined physical and chemical methods but, with tightened legislation, these routes are no longer acceptable. Now, biological treatment is being increasingly adopted as it seems to offer an alternative with the potential for significant cost saving. However, there are significant difficulties in operating bioreactors, such as maintenance of the stability of the microbial communities present in activated sludge plants (ASP). In order to resolve these problems, four major areas need to be considered: (1) the composition of the spent MWF and its inherent biodegradability, (2) the recalcitrant compounds existing in waste MWFs and their impact on microbes, (3) the nature of the microbial consortia and means of optimising it, e.g, temperature and the practical design of the bioreactor and (4) the requirements for nutrient supplements and optimal control conditions. The potential importance of understanding the microbial community has been studied by the use of molecular biological techniques such as polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), fatty acid methyl ester (FAME) and fluorescent in situ hybridization (FISH). The application of attached biofilm bioreactors and thermophilic aerobic technology (TAT) has also been studied. This review describes recent advances in each of these areas.     

Registration of MR and CT images of the liver: comparison of voxel similarity and surface based registration algorithms

The purpose of this work was to determine the feasibility and efficacy of retrospective registration of MR and CT images of the liver. The open-source ITK Insight Software package developed by the National Library of Medicine (USA) contains a multi-resolution, voxel-similarity-based registration algorithm which we selected as our baseline registration method. For comparison we implemented a multi-scale surface fitting technique based on the head-and-hat algorithm. Registration accuracy was assessed using the mean displacement of automatically selected point landmarks. The ITK voxel-similarity-based registration algorithm performed better than the surface-based approach with mean misregistration in the range of 7.7-8.4 mm for CT-CT registration, 8.2 mm for MR-MR registration, and 14.0-18.9 mm for MR-CT registration compared to mean misregistration from the surface-based technique in the range of 9.6-11.1 mm for CT-CT registration, 9.2-12.4 mm for MR-MR registration, and 15.2-19.0 mm for MR-CT registration.     

Large-scale molecular dynamics simulation of DNA: implementation and validation of the AMBER98 force field in LAMMPS

Molecular modelling played a central role in the discovery of the structure of DNA by Watson and Crick. Today, such modelling is done on computers: the more powerful these computers are, the more detailed and extensive can be the study of the dynamics of such biological macromolecules. To fully harness the power of modern massively parallel computers, however, we need to develop and deploy algorithms which can exploit the structure of such hardware. The Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) is a scalable molecular dynamics code including long-range Coulomb interactions, which has been specifically designed to function efficiently on parallel platforms. Here we describe the implementation of the AMBER98 force field in LAMMPS and its validation for molecular dynamics investigations of DNA structure and flexibility against the benchmark of results obtained with the long-established code AMBER6 (Assisted Model Building with Energy Refinement, version 6). Extended molecular dynamics simulations on the hydrated DNA dodecamer d(CTTTTGCAAAAG)(2), which has previously been the subject of extensive dynamical analysis using AMBER6, show that it is possible to obtain excellent agreement in terms of static, dynamic and thermodynamic parameters between AMBER6 and LAMMPS. In comparison with AMBER6, LAMMPS shows greatly improved scalability in massively parallel environments, opening up the possibility of efficient simulations of order-of-magnitude larger systems and/or for order-of-magnitude greater simulation times.     

New York hazardous substances emergency events surveillance: learning from hazardous substances releases to improve safety

Since 1993, the New York State Department of Health, funded by the Agency for Toxic Substances and Disease Registry, has collected data about non-petroleum hazardous substances releases through the Hazardous Substances Emergency Events Surveillance (NYHSEES) project. This study investigates risk factors for hazardous substances releases that may result in public health consequences such as injury or reported health effects. The 6428 qualifying events that occurred during the 10-year-period of 1993-2002 involved 8838 hazardous substances, 842 evacuations, more than 75,419 people evacuated, and more than 3120 people decontaminated. These events occurred both at fixed facilities (79%) and during transport (21%). The causative factors most frequently contributing to reported events were equipment failure (39%) and human error (33%). Five of the 10 chemicals most frequently associated with injuries were also among the 10 chemicals most frequently involved in reported events: sulfuric acid, hydrochloric acid, ammonia, sodium hypochlorite, and carbon monoxide. The chemical categories most frequently associated with events, and with events with adverse health effects were volatile organic compounds (VOCs) and solvents, and acids. Events with releases of hazardous substances were associated with injuries to 3089 people including employees (37%), responders (12%), the general public (29%) and students (22%). The most frequently reported adverse health effects were respiratory irritation, headache, and nausea or vomiting. Most of the injured were transported to the hospital, treated, and released (55%) or treated at the scene (29%). These data have been used for emergency response training, planning, and prevention activities to reduce morbidity and mortality from future events.