Education for the nurse of tomorrow: a community-focused curriculum

A competitive enzyme-linked immunoadsorbent assay (ELISA) technique has been developed to facilitate quantitative analysis of the earliest step in the initiation of the extrinsic pathway of coagulation, i.e., complex formation of factor VII/VIIa with tissue factor. The ELISA measures the binding of biotinylated human plasma factor VII to relipidated recombinant human tissue factor. Quantitation of the relative affinity (expressed as IC50) of any factor VII molecular population or structural analogue for tissue factor can be determined by competitive binding. Subnanomolar concentrations of both wild-type recombinant human factor VII (rFVII) and rFVII(R152Q), a mutation at the FVII activation site, competed effectively with biotinylated plasma-derived factor VII in binding to tissue factor. In contrast, the affinity of rFVII(R79Q), a mutation in the first epidermal growth factor-like domain, was 12-fold lower. Following activation of rFVII(R79Q), its affinity for tissue factor and enzymatic activity increased 4-fold and 6-fold, respectively. For wild-type rFVII, enzymatic activity rose significantly following activation. However, its affinity for tissue factor was unchanged. We conclude that both the activation state of factor VII and the mutation of amino-acid residues within the first epidermal growth factor-like domain may alter the affinity of factor VII for tissue factor.     

Molecular analysis of cellulose biosynthesis in Arabidopsis

Cellulose, an abundant, crystalline polysaccharide, is central to plant morphogenesis and to many industries. Chemical and ultrastructural analyses together with map-based cloning indicate that the RSW1 locus of Arabidopsis encodes the catalytic subunit of cellulose synthase. The cloned gene complements the rsw1 mutant whose temperature-sensitive allele is changed in one amino acid. The mutant allele causes a specific reduction in cellulose synthesis, accumulation of noncrystalline beta-1,4-glucan, disassembly of cellulose synthase, and widespread morphological abnormalities. Microfibril crystallization may require proper assembly of the RSW1 gene product into synthase complexes whereas glucan biosynthesis per se does not.     

High-performance surface-micromachined inchworm actuator

This work demonstrates a polycrystalline silicon surface-micromachined inchworm actuator that exhibits high-performance characteristics such as large force (/spl plusmn/0.5 millinewtons), large velocity range (0 to /spl plusmn/4.4 mm/sec), large displacement range (/spl plusmn/100 microns), small step size (/spl plusmn/10, /spl plusmn/40 or /spl plusmn/100 nanometers), low power consumption (nanojoules per cycle), continuous bidirectional operation and relatively small area (600 /spl times/ 200/spl mu/m/sup 2/). An in situ load spring calibrated on a logarithmic scale from micronewtons to millinewtons, optical microscopy and Michelson interferometry are used to characterize its performance. The actuator consists of a force-amplifying plate that spans two voltage-controlled clamps, and walking is achieved by appropriately sequencing signals to these three components. In the clamps, normal force is borne by equipotential rubbing counterfaces, enabling friction to be measured against load. Using different monolayer coatings, we show that the static coefficient of friction can be changed from 0.14 to 1.04, and that it is load-independent over a broad range. We further find that the static coefficient of friction does not accurately predict the force generated by the actuator and attribute this to nanometer-scale presliding tangential deflections.     

Esophagitis in Sprague-Dawley rats is mediated by free radicals

Free radical-mediated esophagitis was studied during duodenogastroesophageal reflux (mixed reflux) or acid reflux in rats. The influence of reflux on esophageal glutathione levels was also examined. Mixed reflux caused more gross mucosal injury than acid reflux. Gross mucosal injury occurred in the mid-esophagus. Total glutathione (GSH) in the esophageal mucosa of control rats was highest in the distal esophagus. The time course of esophageal GSH in rats treated by mixed reflux showed a significant decrease 4 hr after initiation of reflux, followed by a significant increase from the 12th hour on. Mucosal GSH was increased in both reflux groups after 24 hr but significantly more so in the mixed than in the acid reflux group. The free radical scavenger superoxide dismutase (SOD) prevented esophagitis and was associated with decreased GSH levels. GSH depletion by buthionine sulfoximine (BSO) prevented esophagitis and stimulated SOD production in the esophageal mucosa. It is concluded that gastroesophageal reflux is associated with oxidative stress in the esophageal mucosa. The lower GSH levels in the mid-esophagus may predispose to damage in this area. Duodenogastroesophageal reflux causes more damage than pure acid reflux. Oxidative stress leads to GSH depletion of the esophageal mucosa in the first few hours following damage but then stimulates GSH production. GSH depletion by BSO does not worsen esophagitis since it increases the esophageal SOD concentration.     

Electrochromic WO3−x films with reduced lattice deformation stress and fast response time

Electrochromic properties of electrochemically deposited and etched (EDE) WO_3−x films have been investigated using voltammetry and nanogravimetry to elucidate the amount of residual stress associated with lattice polarization and deformation in WO_3−x nanoparticles. The cathodic WO_3−x deposition from pertungstic acid solution and unusual properties of the cathodic electroetching of the oxide in tetraethyl ammonium chloride solution are reported and elucidated on the basis of Electrochemical Quartz Crystal Nanogravimetry (EQCN) measurements. The stress enhanced resonant frequency shift was observed upon WO_3−x film coloration. However, the stress enhancement appeared to be much lower (up to 4-6 times) than that measured for films synthesized by other methods. The stress reduction in WO_3−x films under study has been attributed to the stress relaxing propensity of EDE film to suppress the compressive stress wave. A considerable isotopic effect has been observed in nanogravimetry of the H⁺ and D⁺ ion intercalation into WO_3−x films. We have found that the isotopic effect is primarily due to the true mass loading difference between hydrogen and deuterium ions, for the same concentration of color centers (2.65 × 10²¹ cm⁻³), since EQCN frequency shifts associated with stress in the film for H⁺ and D⁺ are very close to each other.     

The design of a collision avoidance system for use by Pilots operating on the airport ramp and in taxiway areas

Ground collisions have serious implications from both a safety and a commercial perspective. This paper reports on human computer interaction (HCI) research related to the advancement of a collision avoidance system, for use by Pilots operating on the airport ramp and in taxiway areas. Primarily, this paper focuses on the key findings of this research and the emerging HCI design solution.     

Cover Picture: A Single Polymer Nanowire Photodetector (Adv. Mater. 18/2006)

Redmond and co‐workers report on p. 2379 the successful application of solution‐assisted template wetting to the high‐yield controlled synthesis of poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐co‐(bithiophene)] (F8T2) nanowires (main picture and lower inset). Photoconductivity measurements (schematic in center) yield single‐nanowire device responsivities of ca. 0.4 mA W^–1 and external quantum efficiencies of ca. 0.1 % under monochromatic illumination, comparable with data reported for single inorganic nanowire devices.     

Acid resistance of inorganic polymer binders. 1. Corrosion rate

The resistance to acid-induced corrosion of inorganic polymer (including ??fly ash geopolymer??) binders is examined, by exposing specimens to nitric and sulphuric acids at pH values between 1 and 3, and measuring the corroded depth as a function of exposure time. The inorganic polymer binders are shown to be affected by acid attack by surface corrosion, which contradicts some previous claims of extremely high acid resistance in such binders. Corroded depth is shown to be a more sensitive measure of the performance of inorganic polymer binders than change in mass, because acid attack on the highly-connected aluminosilicate network of an inorganic polymer binder leads to the formation of an apparently intact, but physically weak and porous, reaction product layer on the sample surface, rather than complete disappearance of the binder as is often the case for other binder types. A strong correlation between permeability and resistance to acid attack is noted across a wide range of inorganic polymer formulations, including samples based on fly ash, ground granulated blast furnace slag, and mixtures of the two. The presence of calcium (supplied either by a Class C fly ash or by slag) and of high alkali concentrations each show a positive influence on acid resistance, which is attributed to the reduction in mass transport rates through the finer and more tortuous pore networks of such binders.     

The value of energy audits for SMEs: an Australian example

Energy audits can provide businesses with valuable information and advice about their current energy use and costs and where changes can be made to improve both the environmental performance of the business and their triple bottom line. There is literature on the use of energy audits outside Australia, but little provision of empirical data that would help a business decide whether engagement is economically viable. This paper reports on 49 SME energy audits in Australia, and the results verify that economic returns can vary significantly and alone are not a reason for most SMEs to act. Thus, more will need to be done to engage them as their collective impact on the environment should be a catalyst for action and support from stakeholders.     

Universal intervention effects on substance use among young adults mediated by delayed adolescent substance initiation.

In this article, the authors examine whether delayed substance initiation during adolescence, achieved through universal family-focused interventions conducted in middle school, can reduce problematic substance use during young adulthood. Sixth-grade students enrolled in 33 rural midwestern schools and their families were randomly assigned to 3 experimental conditions. Self-report questionnaires provided data at 7 time points for the Iowa Strengthening Families Program (ISFP), Preparing for the Drug Free Years (PDFY), and control groups through young adulthood. Five young adult substance frequency measures (drunkenness, alcohol-related problems, cigarettes, illicit drugs, and polysubstance use) were modeled as distal outcomes affected by the average level and rate of increase in substance initiation across the adolescent years in latent growth curve analyses. Results show that the models fit the data and that they were robust across outcomes and interventions, with more robust effects found for ISFP. The addition of direct intervention effects on young adult outcomes was not supported, suggesting long-term effects were primarily indirect. Relative reduction rates were calculated to quantify intervention-control differences on the estimated proportion of young adults indicating problematic substance use; they ranged from 19% to 31% for ISFP and from 9% to 16% for PDFY. (PsycINFO Database Record (c) 2010 APA, all rights reserved)