Exotic asphyxiation: interactions between invasive species and hypoxia.

Non-indigenous species (NIS) and hypoxia (<2 mg O l ) can disturb and restructure aquatic communities. Both are heavily influenced by human activities and are intensifying with global change. As these disturbances increase, understanding how they interact to affect native species and systems is essential.

Establishing Cost-Effective Computational Models for the Prediction of Lanthanoid Binding in [Ln(NO)] (with Ln = La to Lu).

Evaluating the efficiency of predictive methods is critical to the processes of upscaling laboratory processes to full-scale operations on an industrial scale. With regard to separation of lanthanoids, there is a considerable motivation to optimize these processes because of immediate use in nuclear fuel cycle operations, nuclear forensics applications, and rare-earth metal recovery. Efficient predictive capabilities in Gibbs free energies of reaction are essential to optimize separations and ligand design for selective binding needed for various radiochemical applications such as nuclear fuel disposition and recycling of lanthanoid fission products into useful radioisotope products.

Structural Characteristics, Population Analysis, and Binding Energies of [An(NO)] (with An = Ac to Lr).

Efficient predictive capabilities are essential for the actinide series since regulatory constraints for radioactive work, associated costs needed for specialized facilities, and the short half-lives of many actinides present great challenges in laboratory settings. Improved predictive accuracy is advantageous for numerous applications including the optimization and design of separation agents for nuclear fuel and waste. One limitation of calculations in support of these applications is that the large variations observed from predictions obtained with currently available methods can make comparisons across studies uncertain.

Structural Analysis of the Complexation of Uranyl, Neptunyl, Plutonyl, and Americyl with Cyclic Imide Dioximes.

Knowledge-based design of extracting agents for selective binding of actinides is essential in stock-pile stewardship, environmental remediation, separations, and nuclear fuel disposal. Robust computational protocols are critical for in depth understanding of structural properties and to further advance the design of selective ligands. In particular, rapid radiochemical separations require predictive capabilities for binding in the gas phase.

Gas chemical adsorption characterization of lanthanide hexafluoroacetylacetonates.

Newly-established adsorption enthalpy and entropy values of 12 lanthanide hexafluoroacetylacetonates, denoted Ln[hfac], along with the experimental and theoretical methodology used to obtain these values, are presented for the first time. The results of this work can be used in conjunction with theoretical modeling techniques to optimize a large-scale gas-phase separation experiment using isothermal chromatography. The results to date indicate average adsorption enthalpy and entropy values of the 12 Ln[hfac] complexes ranging from -33 to -139 kJ/mol K and -299 to -557 J/mol, respectively.

Review of current nuclear fallout codes.

The importance of developing a robust nuclear forensics program to combat the illicit use of nuclear material that may be used as an improvised nuclear device is widely accepted. In order to decrease the threat to public safety and improve governmental response, government agencies have developed fallout-analysis codes to predict the fallout particle size, dose, and dispersion and dispersion following a detonation. This paper will review the different codes that have been developed for predicting fallout from both chemical and nuclear weapons.

Characterization and thermogravimetric analysis of lanthanide hexafluoroacetylacetone chelates.

This work reports the thermodynamic characterizations of organometallic species as a vehicle for the rapid separation of volatile nuclear fission products via gas chromatography due to differences in adsorption enthalpy. Because adsorption and sublimation thermodynamics are linearly correlated, there is considerable motivation to determine sublimation enthalpies. A method of isothermal thermogravimetric analysis, TGA-MS and melting point analysis are employed on thirteen lanthanide 1,1,1,5,5,5-hexafluoroacetylacetone complexes to determine sublimation enthalpies.

Gas-phase detection of solid-state fission product complexes for post-detonation nuclear forensic analysis.

This study presents the first known detection of fission products commonly found in post-detonation nuclear debris samples using solid sample introduction and a uniquely coupled gas chromatography inductively-coupled plasma time-of-flight mass spectrometer. Rare earth oxides were chemically altered to incorporate a ligand that enhances the volatility of the samples. These samples were injected (as solids) into the aforementioned instrument and detected for the first time.

Thermodynamic analysis of volatile organometallic fission products.

The ability to perform rapid separations in a post nuclear weapon detonation scenario is an important aspect of national security. In the past, separations of fission products have been performed using solvent extraction, precipitation, etc. The focus of this work is to explore the feasibility of using thermochromatography, a technique largely employed in superheavy element chemistry, to expedite the separation of fission products from fuel components.

Production of Synthetic Nuclear Melt Glass.

Realistic surrogate nuclear debris is needed within the nuclear forensics community to test and validate post-detonation analysis techniques. Here we outline a novel process for producing bulk surface debris using a high temperature furnace. The material developed in this study is physically and chemically similar to trinitite (the melt glass produced by the first nuclear test).

Development of synthetic nuclear melt glass for forensic analysis.

A method for producing synthetic debris similar to the melt glass produced by nuclear surface testing is demonstrated. Melt glass from the first nuclear weapon test (commonly referred to as trinitite) is used as the benchmark for this study. These surrogates can be used to simulate a variety of scenarios and will serve as a tool for developing and validating forensic analysis methods.

A new approach to improving healthcare personnel influenza immunization programs: a randomized controlled trial.

Background: Healthcare personnel influenza immunization rates remain sub-optimal. Following multiple studies and expert consultations, the "Successful Influenza Immunization Programs for Healthcare Personnel: A Guide for Program Planners" was produced. This trial assessed the impact of the Guide with facilitation in improving healthcare personnel influenza immunization rates in Canadian healthcare organizations.

Fukushima Daiichi: implications for carbon-free energy, nuclear nonproliferation, and community resilience.

Implications of the nuclear power plant accidents at Fukushima Daiichi are explored in this commentary. In addition to questions of nuclear reactor regulatory standards, broader implications on noncarbon-emitting energy production, nuclear nonproliferation objectives, and community resilience and emergency response against catastrophic events are explored.

Excitatory actions of GABA mediate severe-hypoxia-induced depression of neuronal activity in the pond snail (Lymnaea stagnalis).

To characterize the effect of severe hypoxia on neuronal activity, long-term intracellular recordings were made from neurones in the isolated central ring ganglia of Lymnaea stagnalis. When a neurone at rest in normoxia was subjected to severe hypoxia, action potential firing frequency decreased by 38% (from 2.4-1.

Solitary splenic lesions.

Solitary splenic lesions are unusual. A differential diagnosis can be organized around their basic imaging appearance as either predominantly cystic or solid. Other imaging characteristics, including vascular enhancement and activity on Tc-99m sulfur colloid scan, as well as clinical history may narrow the diagnostic possibilities.

A community-based program for cardiovascular health awareness.

Objective: The objective of the Cardiovascular Health Awareness Program (CHAP) is to improve the processes of care related to the cardiovascular health of older adults.

Participants: Two Ontario communities including family physicians (FP), pharmacists, public health units and nurses, volunteer peer health educators, older adult patients and community organizations.

Setting: Community pharmacies and family physician offices.

Ethnic and socioeconomic comparisons of fitness, activity levels, and barriers to exercise in high school females.

The purpose of this study was to determine if high school females differed in individual measures of health-related physical fitness, barriers to exercise, or activity level based on ethnicity or socioeconomic status. A cross-sectional sample consisting of African American (28%), Hispanic (23%), and white (49%) female high school students, 46% from low socioeconomic groups and 54% from moderate or high socioeconomic groups (n = 1314, age = 16.2 +/- 0.

Research on Alzheimer's caregiving in Canada: current status and future directions.

In December 2002, a national workshop was held in Ottawa to guide research directions for the caregiving of people with Alzheimer's disease in Canada. Prior to the workshop, a search was conducted to identify Canadian-based investigators who have conducted research related to caregiving of individuals with cognitive impairment, Alzheimer's disease and other dementia, identify relevant Canadian research studies, and provide an overview of results and themes emerging from this research. This paper summarizes findings from our search for Canadian studies, research themes identified at the national workshop in Ottawa, and recommendations from the workshop.

Reagentless detection and classification of individual bioaerosol particles in seconds.

The rapid chemical analysis of individual cells is an analytical capability that will profoundly impact many fields including bioaerosol detection for biodefense and cellular diagnostics for clinical medicine. This article describes a mass spectrometry-based analytical technique for the real-time and reagentless characterization of individual airborne cells without sample preparation. We characterize the mass spectral signature of individual Bacillus spores and demonstrate the ability to distinguish two Bacillus spore species, B.

Testing young infants with the Welch Allyn suresight non-cycloplegic autorefractor.

Both eyes of 74 healthy 2-12-month-old human infants were refracted twice with the new Welch Allyn SureSight non-cycloplegic autorefractor. At least one reliable estimate of sphere and cylinder was obtained from both eyes of all babies attempted, and 88% of infants contributed two estimates from each eye. These measurements were collected in less than 2 min.

The predictive utility of the Teller acuity cards for assessing visual outcome in children with preterm birth and associated perinatal risks.

We assessed binocular grating visual acuity with the Teller acuity cards (TAC) in 3-36-month-olds at risk for visual disorders. After 3-8 years, each child was assessed with the TAC and with a battery of tests of spatial and non-spatial vision. The initial TAC score: (1) was uncorrelated with any of the later measures; (2) had low positive, but high negative predictive value for the later tests; (3) had low sensitivity, but high specificity for identifying children with and without visual disorders, respectively.