On September 12, 2003, the University of Maryland School of Law's Intellectual Property and Law & Health Care Programs jointly sponsored and convened a roundtable discussion on the future public policy and ethical issues that will likely face the agricultural and microbial genomics sectors of the biotechnology industry. As this industry has developed over the last two decades, societal concerns have moved from what were often local issues, e.g., the safety of laboratories where scientists conducted recombinant DNA research on transgenic microbes, animals and crops, to more global issues. These newer issues include intellectual property, international trade, risks of genetically engineered foods and microbes, bioterrorism, and marketing and labeling of new products sold worldwide. The fast paced nature of the biotechnology industry and its new developments often mean that legislators, regulators and society, in general, must play ''catch up'' in their efforts to understand the issues, the risks, and even the benefits, that may result from the industry's new ways of conducting research, new products, and novel methods of product marketing and distribution. The goal of the roundtable was to develop a short list of the most significant public policy and ethical issues that will emerge as a result of …

A neural network concept derived from an analogy between the immune system and the central nervous system is outlined. The theory is based on a neuron that is slightly more complicated than the conventional McCullogh-Pitts type of neuron, in that is exhibits hysteresis at the single cell level. This added complication is compensated by the fact that a network of such neurons is able to learn without the necessity for any changes in synaptic connection strengths. The learning occurs as a neural consequence of interactions between the network and its environment, with environmental stimuli moving the system around in an N-dimensional phase space, until a point in phase space is reached such that the system's responses are appropriate for dealing with the stimuli. Due to the hysteresis associated with each neuron, the system tends to stay in the region of phase space where it is located. The theory includes a role for sleep in learning. 18 refs., 2 figs.

The Yakima Fisheries Project (YFP) is a supplementation plan for enhancing salmon runs in the Yakima River basin. It is presumed that inadequate spawning and rearing, habitat are limiting, factors to population abundance of spring chinook salmon. Therefore, the supplementation effort for spring chinook salmon is focused on introducing hatchery-raised smolts into the basin to compensate for the lack of spawning habitat. However, based on empirical evidence in the Yakima basin, hatchery-reared salmon have survived poorly compared to wild salmon. Therefore, the YFP has proposed to alter the optimal conventional treatment (OCT), which is the state-of-the-art hatchery rearing method, to a new innovative treatment (NIT). The NIT is intended to produce hatchery fish that mimic wild fish and thereby to enhance their survival over that of OCT fish. A limited application of the NIT (LNIT) has also been proposed to reduce the cost of applying the new treatment, yet retain the benefits of increased survival. This research was conducted to test whether the uncertainty using the experimental design was within the limits specified by the Planning Status Report (PSR).

A number of multiwire, position-sensitive, gas proportional chambers have been constructed which use fast delay line (2.5 ns/cm) readouts to provide trajectory position and angle information for particles near the focal planes of the Energetic Pion Channel and Spectrometer (EPICS) and High Resolution Spectrometer (HRS) at the Clinton P. Anderson Meson Physics Facility (LAMPF). These chambers are two dimensional with anode wires in one direction and cathode wires in the other direction. When operated as ordinary delay line chambers, position resolution of 0.5 mm (FWHM) can be obtained in the cathode direction for short cathode wire lengths. If the drift information from the anodes is used, resolution of less than 0.35 mm (FWHM) can be obtained in this direction. The chambers can be operated at count rates of 5 x 10/sup 5/ pulses/sec with live times of greater than 90 percent. Efficiencies, measured at lower counting rates, are typically greater than 99 percent.

3M has developed technology for selectively removing trace levels of dissolved contaminant materials from liquids using systems operating at flow rates up to 50 gallons per minute. This technology combines active particle chemistries with a particle-loaded membrane to achieve a new medium for liquid waste processing--a spiral wound filter cartridge. This technology has shown success by generating high decontamination factors and reducing contaminants to part per trillion levels. The spiral wound cartridge offers simplified installation, convenient replacement, and clean, easy disposal of a concentrated waste. By incorporating small, high surface area particles (5 to 80 microns) into a sturdy, yet porous, membrane greater removal efficiencies of even trace contaminants can be achieved at higher flow rates than with conventional column systems. In addition, the captive-particle medium prevents channeling of liquids and insures uniform flow across the sorbing particle surface. The cartridges fit into standard, commercially-available housings and whole system capital costs are substantially lower than those of column or reverse osmosis systems. Developmental work at high degrees of water polishing have included removal of mercury from contaminated wastewater, various radionuclides from process water, and organometallic species from surface water discharges. Laboratory testing and on-site demonstration data of these applications show …

This article examines experimental heats of formation and enthalpies obtained from G4 calculations to find that the resonance stabilization of the two unpaired electrons in triplet O₂, relative to the unpaired electrons in two hydroxyl radicals, amounts to 100 kcal/mol.

The microstructural evolution and structural characteristics and transitions in the thin grain-boundary oxide films in a silicon nitride ceramic, specifically between two adjacent grains and not the triple junctions, are investigated to find their effect on the macroscopic fracture properties. It is found that by heat treating a model Si3N4-2wt percent Y2O3 ceramic for {approx}200 hr at 1400 degrees C in air, the fracture toughness can be increased by {approx}100 percent, coincident with a change in fracture mechanism from transgranular to intergranular.

High-resolution transmission electron microscopy (HRTEM) employing focus-variation phase-reconstruction methods is used to image the atomic structure of grain boundaries in a silicon nitride ceramic at a resolution of 0.8 Angstrom

Synchrotron infrared studies of adsorbates on surfaces offer the possibility of probing low frequency vibrational modes and dynamics at high resolution (1 cm{sup {minus}1}, 125 {mu}eV). Extensive experiments have been performed for ordered submonolayers of CO on low index Cu surfaces [({radical}3 {times} {radical}3)R30{degree} CO/Cu(1ll), c(2 {times} 2) CO/Cu(100) and (1 {times} 2) CO/Cu(l10)], in the 100-2500 cm{sup {minus}1} ({approximately}12.5 {minus} 312.5 MeV) range. These are the first IR experiments to directly probe the adsorbate-substrate vibrations for this system. In addition, however, several surprising features are observed including the dipole-forbidden hindered rotation and an unexpected broadband absorption. Two theories have been motivated by this work, and will be compared to our experimental results. The first theory is a cluster calculation by Head-Gordon and Tully, which takes into account the breakdown of the Born-Oppenheimer approximation and predicts lifetimes and frequencies of the vibrational modes for CO/Cu(100). Another Drude-based theory, proposed by Persson, considers the coupling of the conduction electron current to the vibrations of the adsorbates, accounting for the observation of both the broad-band absorption and dipole-forbidden peak.

Topics of discussion included static and dynamic methods for polarizing nuclei, proton and pion nucleus scattering experiments, and possible future experiments at LAMPF. Separate abstracts were prepared for 11 papers in this report. (DWL)

A preliminary report is presented of a positron-annihilation study of the equilibrium vacancy ensemble in aluminum using one- and two-dimensional angular correlation of annihilation radiation (ACAR) measurements versus temperature. The annihilation characteristics of a positron from the Bloch state, and the monovancy- and divacancy-trapped states have been calculated self-consistently within a supercell, including many-body enhancement effects, and are compared with experiment. 4 figures.

Positron-annihilation characteristics in a monovacancy and a divacancy in aluminium have been calculated self-consistently using a local density functional formalism, into which the many-body enhancement effects have been incorporated. Results for the theoretical two-dimensional angular correlation of annihilation radiation spectra are compared to experimental results obtained from an aluminum single crystal at 20/sup 0/C, where positrons annihilate from a Bloch-state, and at higher temperatures, 500/sup 0/C and 630/sup 0/C, where they annihilate primarily from vacancy-trapped states.

The use of low dielectric constant materials in the on-chipinterconnect process reduces interconnect delay, power dissipation andcrosstalk noise. To achieve the requirements of the ITRS for 2007-2009minimal sidewall damage from etch, ash or cleans is required. In chemicalvapor deposited (CVD) organo-silicate glass (OSG) which are used asintermetal dielectric (IMD) materials the substitution of oxygen in SiO2by methyl groups (-CH3) reduces the permittivity significantly (from 4.0in SiO2 to 2.6-3.3 in the OSG), since the electronic polarizability islower for Si-C bonds than for Si-O bonds. However, plasma processing forresist stripping, trench etching and post-etch cleaning removes C and Hcontaining molecular groups from the near-surface layer of OSG.Therefore, compositional analysis and chemical bonding characterizationof structured IMD films with nanometer resolution is necessary forprocess optimization. OSG thin films as-deposited and after plasmatreatment are studied using X-ray absorption spectroscopy (XAS) andelectron energy loss spectroscopy (EELS). In both techniques, the finestructure near the C1s absorption or energy loss edge, respectively,allows to identify C-H, C-C, and C-O bonds. This gives the opportunity todifferentiate between individual low-k materials and their modifications.The O1s signal is less selective to individual bonds. XAS spectra havebeen recorded for non-patterned films and EELS spectra for patternedstructures. The chemical bonding is compared for as-deposited …

One- and two-dimensional angular correlation of positron-electron annihilation radiation (1D and 2D-ACAR) data have been obtained between 293 and 903 K for single crystals of aluminum. The peak counting rates vs temperature, which were measured using the 1D-ACAR technique, provide a model independent value for the temperature dependence of the positron trapping probability. Using these results it is possible to strip out the Bloch state contribution from the observed 2D-ACAR surfaces and then compare the resulting defect ACAR surfaces to calculated 2D-ACAR surfaces for positrons annihilating from the Bloch, monovacancy, and divacancy-trapped states. The result of this comparison is that the presence of an increasing equilibrium divacancy population is consistent with the observed temperature dependence of ACAR data at high temperature in Al and that the present results when compared to earlier studies on Al indicate that the ratio of the trapping rates at divacancies and monovacancies is of order two.

Elongated Si nitride grains produced during densification in a liquid phase can increase the fracture toughness, but this depends on the activation of intergranular rather than transgranular fracture. Bridging in the crack wake by elongated grains and pullout of some of these grains suggest that the crack wake mechanisms that contribute to toughening of whisker-reinforced ceramics can also operate in Si nitrides containing elongated grains. With diameters of the larger elongated grains approaching 9 {mu}m, strengths > 800 MPa have been achieved along with Weibull moduli, but clustering of these larger elongated grains must be avoided. Fatigue of these toughened Si nitrides is influenced by silicate grain boundary phases. Design of toughened Si nitrides must consider effects of silicate phase composition and content on fatigue and creep. 8 figs, 18 refs.

We have studied microwave dynamic cooling of ZF and H nuclei in mixtures of 1,1,1,3,3,3-hexafluoro-2-propanol and water, doped with Cr(V) complex. Equal spin temperatures of the two nuclei are produced, and the highest spin polarizations (/approximately/80%) are found in mixtures near the eutectic ratio. The high fluorine content and polarization make this a suitable material for polarized nuclear scattering experiments. 11 refs., 3 figs., 1 tab.

The Oak Ridge K-25 Site Toxic Substances Control Act (TSCA) Incinerator has been undergoing a series of routine tests to determine uranium partitioning to the stack, scrubber waters, and bottom ash. This paper discusses the results of the most recent experiment in which relatively high rates of uranium stack gas emissions were identified: 6.11 g/h or 8 wt % based on the uranium feed. These data are compared with earlier data, and an empirical correlation is suggested between the stack emissions of uranium and the product of the uranium and chlorine concentration of the feed. This is consistent with certain findings with other metals, in which increasing chlorine feed contents led to increasing emissions.

IRRAS spectra of NO/Cu(111) and ({radical}3 {times} {radical}3)R30{degrees} coverage of CO/Cu(111) in the range 3000--180 cm{sup {minus}1} show both the adsorbate internal modes and features assigned to the hindered rotational modes. These dipole-forbidden features are characterized by asymmetric (mostly negative) absorption lineshapes and are accompanied by a change in broadband absorption. The shape and intensity of this broadband absorption is well accounted for by a scattering model.

This article discusses the mechanism for plasma hydrogenation of graphene.

The toughness of self-reinforced silicon nitride ceramics is improved by enhancing crack deflection and crack bridging mechanisms. Both mechanisms rely on the interfacial debonding process between the elongated {Beta}-Si{sub 3}N{sub 4} grains and the intergranular amorphous phases. The various sintering additives used for densification may influence the interfacial debonding process by modifying the thermal and mechanical properties of the intergranular glasses, which will result in different residual thermal expansion mismatch stresses; and the atomic bonding structure across the {Beta}-Si{sub 3}N{sub 4} glass interface. Earlier studies indicated that self-reinforced silicon nitrides sintered with different rare earth additives and/or different Y{sub 2}O{sub 3}:AI{sub 2}0{sub 3} ratios could exhibit different fracture behavior that varied from intergranular to transgranular fracture. No studies have been conducted to investigate the influence of sintering additives on the interfacial fracture in silicon nitride ceramics. Because of the complexity of the material system and the extremely small scale, it is difficult to conduct quantitative analyses on the chemistry and stress states of the intergranular glass phases and to relate the results to the bulk properties. The influence of different sintering additives on the interfacial fracture behavior is assessed using model systems in which {Beta}-Si{sub 3}N{sub 4}whiskers are embedded in …

The costs associated with environmental restoration and waste management at both government and private facilities are burdensome, and continue to grow. The Department of Energy estimates that over one million samples, many containing radioactive components, will be analyzed per annum to support remediation programs at its 4000 sites. The development and implementation of new analytical technologies can significantly reduce the high costs associated with these programs. Disk solid-phase extraction technology has been proven to be highly effective for sample preparation in the analysis of organic compounds, waste waters, and other aqueous samples. Disk technology significantly improves sample throughput, while reducing secondary waste and costs. Moreover, many of the hazardous chemicals associated with traditional procedures are eliminated. This technology may be readily automated and lends itself to field applications. Through a Cooperative Research and Development Agreement, the 3M Company and Argonne National Laboratory are expanding this technology to address sample preparation and recovery of radionuclides from aqueous samples, i.e., surface, ground, and drinking waters. Disks have been developed which demonstrate high selectivity and great affinity for important radionuclides, including {sup 99}Tc, {sup 89/90}Sr, and {sup 226/228}Ra.

General Atomics is designing, testing and fabricating a system for supplying cryogenic targets for the University of Rochester`s OMEGA laser system. A prototype system has demonstrated the filling of 1 mm diameter, 3 {micro}m wall plastic spheres to 111 MPa (1,100 atm) with deuterium and then cooling to 18 K to condense the fuel. The production design must be capable of routinely filling and cooling targets with a 50/50 mix of deuterium and tritium and transferring them to a device which places the targets into the focus of 60 laser beams. This paper discusses the design and analysis of the production Fill/Transfer Station cryostat. The cryostat has two major components, a fixed base and a removable dome. The joint between the base and the dome is similar to a bayonet fitting and is sealed by a room temperature elastomeric o-ring. Since the cryostat must be housed in a glovebox, its design is driven strongly by maintenance requirements. To reach the equipment inside the cryostat, the dome is simply unbolted and lifted. The inside of the cryostat is maintained at 16 K by a closed loop helium flow system. Gaseous helium at about 1.4 MPa (200 psi) flows through tubes which …

Even though theoretical estimates predict response times for the photo emission process of electrons from a negative electron affinity GaAs photo emitter in excess of hundreds of picoseconds, recent measurements found electron bunch durations of 40 ps or less. This work presents precise measurements of picosecond electron bunches from a negative affinity bulk GaAs photo cathode and develops a model which explains the measured bunch durations as well as the observed bunch shapes. The bunch shape turns out to be independent from the quantum efficiency of the photo emitter.

Hyperspectral plant signatures can be used as a short-term, as well as long-term (100-yr timescale) monitoring technique to verify that CO2 sequestration fields have not been compromised. An influx of CO2 gas into the soil can stress vegetation, which causes changes in the visible to nearinfrared reflectance spectral signature of the vegetation. For 29 days, beginning on July 9th, 2008, pure carbon dioxide gas was released through a 100-meter long horizontal injection well, at a flow rate of 300 kg/day. Spectral signatures were recorded almost daily from an unmown patch of plants over the injection with a ''FieldSpec Pro'' spectrometer by Analytical Spectral Devices, Inc. Measurements were taken both inside and outside of the CO2 leak zone to normalize observations for other environmental factors affecting the plants.