The location of parasites within individual hosts is often treated as a static trait, yet many parasite species can occur in multiple locations or organs within their hosts. Here, we apply distributional heat maps to study the within- and between-host infection patterns for four trematodes (Alaria marcianae, Cephalogonimus americanus, Echinostoma spp. and Ribeiroia ondatrae) within the amphibian hosts Pseudacris regilla and two species of Taricha. We developed heatmaps from 71 individual hosts from six locations in California, which illustrate stark differences among parasites both in their primary locations within amphibian hosts as well as their degree of location specificity. While metacercariae (i.e., cysts) of two parasites (C. americanus and A. marcianae) were relative generalists in habitat selection and often occurred throughout the host, two others (R. ondatrae and Echinostoma spp.) were highly localised to a specific organ or organ system. Comparing parasite distributions among these parasite taxa highlighted locations of overlap showing potential areas of interactions, such as the mandibular inner dermis region, chest and throat inner dermis and the tail reabsorption outer epidermis. Additionally, the within-host distribution of R. ondatrae differed between host species, with metacercariae aggregating in the anterior dermis areas of newts, compared with the posterior dermis area in frogs. The ability to measure fine-scale changes or alterations in parasite distributions has the potential to provide further insight about ecological questions concerning habitat preference, resource selection, host pathology and disease control.

Identifying developmental endophenotypes on the pathway between genetics and behavior is critical to uncovering the mechanisms underlying neurodevelopmental conditions. In this proof-of-principle study, we explored whether early disruptions in visual attention are a unique or shared candidate endophenotype of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). We calculated the duration of the longest look (i.e., peak look) to faces in an array-based eye-tracking task for 335 14-month-old infants with and without first-degree relatives with ASD and/or ADHD. We leveraged parent-report and genotype data available for a proportion of these infants to evaluate the relation of looking behavior to familial (n = 285) and genetic liability (using polygenic scores, n = 185) as well as ASD and ADHD-relevant temperament traits at 2 years of age (shyness and inhibitory control, respectively, n = 272) and ASD and ADHD clinical traits at 6 years of age (n = 94).

Results showed that longer peak looks at the face were associated with elevated polygenic scores for ADHD (β = 0.078, p = .023), but not ASD (β = 0.002, p = .944), and with elevated ADHD traits in mid-childhood (F(1,88) = 6.401, p = .013, $\eta _p^2$=0.068; ASD: F (1,88) = 3.218, p = .076), but not in toddlerhood (ps > 0.2). This pattern of results did not emerge when considering mean peak look duration across face and nonface stimuli. Thus, alterations in attention to faces during spontaneous visual exploration may be more consistent with a developmental endophenotype of ADHD than ASD. Our work shows that dissecting paths to neurodevelopmental conditions requires longitudinal data incorporating polygenic contribution, early neurocognitive function, and clinical phenotypic variation.

The objectives of this work are to prepare and characterize iodine-rich thermites and reactive materials for potential application in bio-agent defeat. Iodine-rich compositions were prepared using metal iodate oxidizers in combination with aluminum fuel. Higher iodine contents were achieved using iodine-rich additives, tetraiodoethylene and tin tetraiodide. Reactivity during rapid combustion was evaluated for both nanoscale and micron-scale materials. The nanoscale materials were evaluated directly using a spark-initiated pan dent test. The micron-scale materials were mixed with 50% of nano Al/MoO3 and also evaluated with the pan dent test. The results for the mixed material were shown to fit well to a linear combination of the expected dent for each component, based on a rapid reaction. Results of the pan dent test were used to down-select micron thermites for further testing. Bismuth iodate was synthesized by precipitation from nitric acid solutions. The average particle size was controlled by the addition rate, and sizes included 95 nm (amorphous structure), and 330 nm and 3 micron (both crystalline). Additional sizes were produced by ball milling the 3 micron material, giving 1 micron and 350 nm sizes. Fluoropolymers were included in some compositions to provide additional biocidal products, namely HF, that could be produced from reaction of AlF3 product with water.

Molten deposits based on calcium-magnesium alumino-silicates (CMAS), originating from siliceous debris ingested with the intake air, represent a fundamental threat to progress in gas turbine technology by limiting the operating surface temperature of coated components. The thermomechanical and thermochemical aspects of the CMAS interactions with thermal-barrier coatings, as well as the current status of mitigating strategies, are discussed in this article. Key challenges and research needs for developing adequate solutions are highlighted.

The objectives of this work are to characterize thermite initiation processes and thresholds, and to develop thermite reactive trains, where a sensitive nanothermite ignites an insensitive micron thermite, which produces little gas. Nanothermites, including Al/AgIO3, Al/Bi2O3, Al/MoO3, Al/Fe3O4, and Ti/AgIO3, were characterized for their ignition behavior by spark and resistive heating. Energies for spark and thermal initiation were as low as 9 and 140 μJ, respectively. Thermal initiation results were consistent with local temperature as the main controlling factor. The propagation rate of the Al/Fe3O4 nanothermite was about 100X slower than that of the other nanothermites. This low reactivity is attributed to the high volatilization temperature and high melting point of the oxidizer. Mixing of 90% Al/Fe3O4 nanothermite with 10% of a more sensitive, high-gas-producing nanothermite gave materials with the same sensitivity as the sensitive nanothermite. Thus, the mixture provides a safer sensitive nanothermite. Thermites with micron-scale ingredients were pressed into pellets and ignited with small amounts of nanothermite. Gas production of micron thermite compositions was reduced by adding the intermetallic composite, Ti/2B, or excess iron. In both cases, a single hot mass was produced, while the pure micron Al/Fe2O3 produced a dispersion of particles.

The world's older population is projected to rise to some two billion people in the next 50 years. The health of older adults deteriorates with increasing age and creates greater demand for healthcare resources. Prevalence of the metabolic syndrome in older adults is causing concern due to its interplay between type 2 diabetes, obesity and associated morbidity and mortality. This call to action discusses comorbidities associated with type 2 diabetes and obesity in the older population and its impact on patients. We cover several topics to consider when designing prevention and treatment strategies for older adults and areas for improvement in our care of this special population are discussed. We know that dietary, exercise and weight-loss interventions are effective. However, these strategies require effort by both patient and physician. If all parties responsible in patient care take action, a change in lifestyle can lead to longer, healthier lives in older adults.

Cortical neurons selective for the direction of motion often exhibit some limited response to motion in their nonpreferred directions. Here we examine the dependence of neuronal direction selectivity on stimulus contrast, both for first-order (luminance-modulated, sine-wave grating) and second-order (contrast-modulated envelope) stimuli. We measured responses from single neurons in area 18 of cat visual cortex to both kinds of moving stimuli over a wide range of contrasts (1.25–80%). Direction-selective contrast response functions (CRFs) were calculated as the preferred-minus-null difference in average firing frequency as a function of contrast. We also applied receiver operating characteristic analysis to our CRF data to obtain neurometric functions characterizing the potential ability of each neuron to discriminate motion direction at each contrast level tested. CRFs for sine-wave gratings were usually monotonic; however, a substantial minority of neurons (35%) exhibited nonmonotonic CRFs (such that the degree of direction selectivity decreased with increasing contrast). The underlying preferred and nonpreferred direction CRFs were diverse, often having different shapes in a given neuron. Neurometric functions for direction discrimination showed a similar degree of heterogeneity, including instances of nonmonotonicity. For contrast-modulated stimuli, however, CRFs for either carrier or envelope contrast were always monotonic. In a given neuron, neurometric thresholds were typically much higher for second- than for first-order stimuli. These results demonstrate that the degree of a cell's direction selectivity depends on the contrast at which it is measured, and therefore is not a characteristic parameter of a neuron. In general, contrast response functions for first-order stimuli were very heterogeneous in shape and sensitivity, while those for second-order stimuli showed less sensitivity and were quite stereotyped in shape.

This study involves an investigation of the mechanism underlying activating effects of inorganic additives on the oxidation of aluminum. The oxidation of nano aluminum powders in air was characterized by variable temperature x-ray powder diffraction and thermogravimetric analysis. For a 33-nm aluminum powder the aluminum oxide produced by air oxidation was poorly crystallized until the sample was heated to above 1050°C, where the alpha-alumina phase crystallized. For a mixture of the aluminum with cryolite, crystallization of oxide phases is enhanced, with Na-Al-O phases evident at 550°C and above. Fluorine is lost from the sample between 550 and 850°C, presumably due to reaction with moisture to produce HF. In a similar experiment with aluminum and silver molybdate, the only crystalline product was alpha-alumina, which was observed at 550°C and higher. The general result is that alpha-alumina, the ultimate product in most cases, crystallized at a lower temperature when activating agents were present.

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

Nanometer aluminum powders have been prepared from the catalytic thermal decomposition of aluminum hydride adducts in organic solvents. This process provides excellent control of particle size and uniformity with batch particle sizes ranging from 50 to 600 nm. Variables affecting particle size were explored, including reaction temperature, catalyst concentration, and adducting amine concentration. Passivation techniques of the reactive aluminum powders were established for safe handling in air. Samples were mainly characterized by scanning electron microscopy and thermogravimetric analysis.

Diamond windows were heated at 700-900 °C in air for short times to better define the limits of application at high temperature. The infrared (IR) transmission of polished chemical vapor deposition (CVD) diamond windows was reduced after heating in a furnace at 800 °C for 75 s, while heating at 700 °C for 75 s produced little change. The 800 °C heating caused increased visible light scatter, and increased scatter appears to be mainly responsible for the reduced IR transmission. The forward scatter at 10.6 μm for the CVD diamond samples was 0.8% before heating, 2.8% after heating at 800 °C for 75 s, and 6.2% after heating at 800 °C for 255 s. Single crystal (110) type IIa diamond exhibited little change in IR transmission when heated at 800 °C in air for 255 s, while heating for 555 s at 800 °C caused a significant drop in IR transmittance (6-12%). A slight drop in IR transmittance (1-5%) occurred for a type IIa diamond when heated at 900 °C for 45 s. The etched surfaces were characterized by differential interference contrast optical microscopy, scanning electron microscopy, and Talystep surface profiles. Etched features are concentrated at grain boundaries (for the CVD samples) and at sites with residual damage from mechanical polishing that could not be seen before the heat treatment. Deep etch pits formed at grain boundaries that extend into the bulk of samples.