Using Micro-Electro-Mechanical-Systems (MEMS) technologies, we have developed silicon wafer-based platinum microelectrode arrays (MEAs) modified with glutamate oxidase (GluOx) for electroenzymatic detection of glutamate in vivo. These MEAs were designed to have optimal spatial resolution for in vivo recordings. Selective detection of glutamate in the presence of the electroactive interferents, dopamine and ascorbic acid, was attained by deposition of polypyrrole and Nafion. The sensors responded to glutamate with a limit of detection under 1 mu M and a sub-1-second response time in solution. In addition to extensive in vitro characterization, the utility of these MEA glutamate biosensors was also established in vivo. In the anesthetized rat, these MEA glutamate biosensors were used for detection of cortically-evoked glutamate release in the ventral striatum. The MEA biosensors also were applied to the detection of stress-induced glutamate release in the dorsal striatum of the freely-moving rat.

The soybean cyst nematode (SCN), Heterodera glycines, is a major yield limiting pest of soybean (Glycine max). Current SCN management strategies include resistant soybean varieties and rotation with non-host crops. Increased adoption of the early soybean production system (ESPS) combined with a greater incidence of winter weeds from no-tillage practices may increase the population density of SCN during the noncrop period since several winter weeds and cover crops are hosts for SCN. A field experiment with a split-strip design was conducted over three years to evaluate whether SCN reproduced on weeds and cover crops during the noncrop period. Winter weeds and crimson clover roots were examined for females and cysts with eggs. The soil was sampled to determine if an increase in SCN egg population density occurred. We found no indication of SCN reproduction on winter weeds during the noncrop period or on the cover crop crimson clover. Accepted for publication 2 November 2006. Published 26 February 2007.

We describe the selective measurement of extracellular glutamate concentration in rodent brain using ceramic-based platinum microelectrode arrays (MEAs) coated with electropolymerized, over-oxidized polypyrrole (OPP) as a permselective barrier to interference from dopamine and ascorbate. OPP-coated MEAs displayed similar sensitivity (97 +/- 9 nA microM(-1) cm(-2)) and response time (ca. 1 s) to glutamate as previously described Nafion-coated MEAs but, unlike Nafion-coated MEAs, were unresponsive to 5 microM dopamine. Such OPP-coated MEAs afforded selective detection of evoked glutamate release in the dopamine-rich striatum of the mouse brain.

In designing an amperometric l-glutamate biosensor based on the electrochemical detection of enzymatically generated H2O2, the key challenges are selectivity against electrooxidizable interferents, micromolar detection limit, and response time of seconds or less. With these issues in mind, a glutamate microbiosensor consisting of Pt black (PtBlk) electrodeposited on a 125-μm-dia. Pt wire with a permselective film of electropolymerized, overoxidized polypyrrole (OPP) and a top layer of l-glutamate oxidase (l-GluOx) crosslinked with glutaraldehyde was constructed. The OPP film permits passage of H2O2 to the electrode surface while rejecting the common interferents of brain extracellular fluid, ascorbate (AA) and dopamine (DA). The PtBlk treatment of Pt electrodes was adopted since the microscale roughness of PtBlk increases the effective surface area of the electrode and promotes electrochemical H2O2 oxidation at lower potential. This microbiosensor was highly sensitive (80±10nAμM−1cm−2) to l-glutamate at 450mV versus Ag/AgCl, a significantly lower potential than the ∼700mV used with most similar l-glutamate sensors prepared on polished Pt electrodes. Notably, microbiosensor response to both AA and DA was undetectable at concentrations exceeding physiological extracellular concentrations of these compounds. The described l-glutamate biosensor also showed excellent response time (∼1–2s) and temporal stability (∼3 week half-life). In addition, this microbiosensor was robust enough for insertion into live brain tissue where it responded rapidly to l-glutamate, but was insensitive to dopamine.

The objective of this work was to study the differences in the ultrasonic weld strength of polypropylene compounds with different fillers. The fillers were calcium carbonate, talc, mica, and glass fibers. The welder parameters were varied to determine the optimum set. These welder parameters were the weld time, weld force, trigger force, and amplitude. The results indicated that the weld time had the greatest effect on the weld strength of each of the filled compounds. Unfilled polypropylene had the highest weld strength under the optimum welding conditions, which were used as the baseline welding conditions. For each given filler, the weld strength was reduced as the filler loading increased. (C) 2004 Wiley Periodicals, Inc.

This review is based on the findings of a consultation meeting involving consultants in travel medicine and focusing on the risks of cholera to the traveller. Cholera is a severe diarrhoeal disease transmitted via the faeco-oral route and commonly associated with poor sanitation. Between the years of 1995 and 2001, the WHO reported 1829 cases of cholera in developed countries, the majority of which were imported. However, it is believed that this figure reflects less than 10% of the true incidence of cholera due to milder cases being unrecognised, as well as significant underreporting. Travellers to epidemic countries may be at increased risk of contracting cholera if they ingest contaminated food or water. It has been estimated that there are 0.2 cases of cholera per 100,000 European and North American travellers, though there is some evidence that this rate is higher. Oral vaccines are a necessary and welcome advance as, in addition to preventing illness, they can minimise the possibility of transmission of cholera to disease-free regions. The morbidity from cholera can range from asymptomatic or oligosymptomatic infection to disruption of holiday and business plans, or even severe toxicity and dehydration. If untreated, severe illnesses can be fatal, although fatalities have not been reported among travellers for many years.

New, reinforced {1 1 0}〈110〉 textured Ag/Ni-alloys composite ribbons were developed as possible substrates for coated conductors without any buffer layer. The texture quality and tensile strength were investigated. A new technique to bond the Ag and Ni or alloy layers through a Cu foil was presented. The Ag/Ni-alloys composite ribbons were fabricated by choosing proper sintering processing to bond the different layers followed by cold rolling and recrystallization. A thin Cu foil was intercalated between the initial Ag and Ni or alloy pieces to get a tough bond. A unique and stable {1 1 0}〈110〉 annealing texture was obtained in 300 μm thick Ag/Ni composite ribbon after annealing. X-ray ODF analysis and EBSD measurements in the top Ag layer showed distribution of misorientation angles around 10–15°. A {1 1 0}〈110〉 texture was also found in ribbons as thin as 50 μm, which cannot be obtained with pure Ag ribbons. A pronounced reduction of Ag amount was obtained in 60 μm thick Ag/NiCrV ribbons, with a textured Ag top layer being as thin as 7 μm. The amount of Ag was decreased by 75% compared to pure Ag ribbons of the same thickness. A strong enhancement of the mechanical properties was observed. The yield strength σ0.2 at 77 K was 220 MPa for Ag/NiCrV ribbons, i.e. considerably higher than the 30 MPa for pure Ag ribbons.

From the Book:ForewordSo you want to make a living as a game artist? The crucial words being make a living.If you want to develop the skills necessary to land a job making a living as a game artist, then you are looking at the right book. I should know for I have spent the last ten years hiring computer game artists. I have sifted through thousands of demo reels, resumes, Web sites, CDs, and resume submissions on every imaginable type of media. In short, if you master what Chad and Eric Walker have laid out in Game Modeling Using Low Polygon Techniques then you will increase your odds of getting a job in the game industry astronomically.This book will help you win the war against the term "starving artist." I have always hated this term because I was always the kid looking out the window or drawing cool pictures, and it was predicted that I would probably be an artist when I grew up (the word "starving" implied by the worried look in my parents' eyes and their wringing hands). With computer technology being what it is today, artists have become more and more in demand as the personal computer has brought with it the computer game, the Internet, and a host of other technologies that demand more and newer content. This book will not only help you develop 3D assets that are applicable to games, but also for the Web sites that are increasingly turning to 3D content so viewers can see their products in real time 3D.Keep in mind that the fate of the starving artist doesn't need to be yours. You can expect above poverty level salaries as a computer artist and this book is definitely the place to start.Luke Ahearn, Art DirectorThe Army Game Project

Texture development in pure Ag was investigated in order to obtain {110}⟨uvw⟩ textured Ag ribbons that can be used as a substrate for YBa2Cu3O7 superconducting coated tapes without any buffer layer. The starting material was 99.95% pure commercial Ag foils. A 20% deformation reduction was used at each step of the cold rolling process after which an optimal annealing was achieved at 800 °C for 4 h in a primary vacuum. This process leads to large-grain ribbons with the {110}⟨112⟩ orientation. A sharp and pure texture is obtained with a FWHM smaller than 6° in the three x-ray pole figures that were used to calculate the orientation distribution function. Crystallographic orientation maps achieved by electron back-scattering diffraction show a misorientation from the normal direction of less than 4°. A twinning mechanism is used to explain the formation of the {110}⟨112⟩ texture. The stability of the {110}⟨112⟩ texture is confirmed by further annealings up to 900 °C, a practical temperature for coated tapes preparation. Lengths up to 25 cm with a uniform {110}⟨112⟩ texture have been obtained.

A Reply to the Comment by Ryusuke Ikeda.Received 10 December 1998DOI:https://doi.org/10.1103/PhysRevLett.82.3379©1999 American Physical Society

We present scanning tunneling spectroscopy (STS) investigations of high temperature superconductors illustrating the very unusual characteristics of the superconducting gap, and the intimate relation existing between the superconducting and the normal-state gap (pseudogap). A unique feature of STS is to probe the local density of quasiparticle states bound to individual vortices. The vortex core spectroscopy sheds new light on the pseudogap and the microscopic nature of HTS. The experiments reviewed here suggest that HTS are in a regime very different from BCS, approaching the crossover to Bose-Einstein condensation.

We present results of electronic Raman-scattering experiments in differently doped YBa 2 Cu 3 O 6+x . In B 2g symmetry, an analysis of the data in terms of a memory function approach is presented and dynamical relaxation rates Γ (ω, T) and mass-enhancement factors 1 + λ(ω, T) for the carriers are obtained. Starting from temperatures T > 180K, Γ(ω, T) and 1 + λ(ω,T) are extrapolated to lower temperatures and used to re-calculate Raman spectra. By comparison with our data, we find a loss of spectral weight between T c < T < T* at all doping levels x. T* is comparable to the pseudogap temperature found in other experiments. Below T c , the superconducting gap is observed. It depends on x and scales with T c whereas the energy scale of the pseudogap remains the same.

Torque magnetometry is a powerful method for probing superconducting anisotropy in the mixed state. In order to use the three-dimensional anisotropic London model to analyze torque data, the vortex lattice must be in a reversible state, a state normally restricted to a narrow range close to the upper critical-field boundary ${H}_{c2}(T)$ because of large pinning effects that set in at lower temperatures $T.$ We show that the application of an additional oscillating magnetic field perpendicular to the main field $B$ leads to a fast depinning of the vortex lattice. This vortex-shaking process dramatically extends the reversible domain in the $(H,T)$ phase diagram, and thus the range in which torque investigations can be made.

With the development of the novel crucible material BaZrO3 a new class of 123 - single crystals has become available, the purity of which reaches now semiconductor grade (> 99.995%). Due to the high purity the experiments are not longer obscured by residual impurities and the influence of different oxygen content and distributions could be studied in detail. This has given way to several new findings and to better basic understanding of the physics of high Tc superconductors. Examples for the impact of this new crystal generation on physics are the reversible suppression of the so called fishtail effect, which is accompanied with the absence of the Schottky anomaly in low temperature specific heat and the calorimetric observation of the vortex lattice melting. On such samples it is possible to observe the vortex lattice by STM without any surface conditioning and to study the influence of pinning centers such as twin boundaries and oxygen vacancies on vortices.