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[en] U.S. Department of Energy (DOE) has monitored groundwater on the Hanford Site since the 1940s to help determine what chemical and radiological contaminants have made their way into the groundwater. As regulatory requirements for monitoring increased in the 1980s, there began to be some overlap between various programs. DOE established the Groundwater Performance Assessment Project (groundwater project) in 1996 to ensure protection of the public and the environment while improving the efficiency of monitoring activities. The groundwater project is designed to support all groundwater monitoring needs at the site, eliminate redundant sampling and analysis, and establish a cost-effective hierarchy for groundwater monitoring activities. This document provides the quality assurance guidelines that will be followed by the groundwater project. This QA Plan is based on the QA requirements of DOE Order 414.1C, Quality Assurance, and 10 CFR 830, Subpart A--General Provisions/Quality Assurance Requirements as delineated in Pacific Northwest National Laboratory's Standards-Based Management System. In addition, the groundwater project is subject to the Environmental Protection Agency (EPA) Requirements for Quality Assurance Project Plans (EPA/240/B-01/003, QA/R-5). The groundwater project has determined that the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD, DOE/RL-96-68) apply to portions of this project and to the subcontractors. HASQARD requirements are discussed within applicable sections of this plan
[en] Rhesus monkey rhadinovirus (RRV) is a γ-2-herpesvirus that is closely related to Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8). Lack of an efficient culture system to grow high titers of virus, and the lack of an in vivo animal model system, has hampered the study of KSHV replication and pathogenesis. RRV is capable of replicating to high titers on fibroblasts, thus facilitating the construction of recombinant rhadinoviruses. In addition, the ability to experimentally infect naieve rhesus macaques with RRV makes it an excellent model system to study γ-herpesvirus replication. Our study describes, for the first time, the construction of a GFP-expressing RRV recombinant virus using a traditional homologous recombination strategy. We have also developed two new methods for determining viral titers of RRV including a traditional viral plaque assay and a quantitative real-time PCR assay. We have compared the replication of wild-type RRV with that of the RRV-GFP recombinant virus in one-step growth curves. We have also measured the sensitivity of RRV to a small panel of antiviral drugs. The development of both the recombination strategy and the viral quantitation assays for RRV will lay the foundation for future studies to evaluate the contribution of individual genes to viral replication both in vitro and in vivo
[en] This paper discussed the barriers and drivers for the implementation of biorefinery technology in the forestry industry. A multi-criteria decision making (MCDM) methodology was used by a panel of industry experts. The objective, drivers and barriers, and the decision structure and weighting procedure were established during a pre-panel phase. An analytic hierarchy process (AHP) was then applied to compare qualitative criteria. Pair-wise criteria were used to determine the importance of each driver and barrier. Drivers for the implementation of biorefineries included the opportunity to ensure short-term profitability; the provision of raw materials at competitive prices; potential financial incentives; and the opportunity to transform the forestry business model and increase its market value. Barriers included uncertainty in relation to government policies for biorefineries; high technology risks; the need for partnerships; and the fact that many industry members favour short-term decision-making. Results of the study showed that the most significant barrier was related to risk. 5 refs., 3 tabs., 3 figs.
[en] This article provided a literature review of emerging technologies for ethanol production in Canada. A multi-criteria decision making (MCDM) panel was used to weigh critical metrics for evaluating the potential of emerging forest biorefinery technologies for bio-ethanol production. The 3-step methodology identified key factors for evaluating technology pathways. Key factors were applied to a group of selected technologies in order to collect data. All previous criteria were weighted through the MCDM panel in order to rank the technologies, which included biochemical pathway and thermochemical pathway production processes. Criteria included return on investment; feedstock flexibility; technology risk; energy and integration; products and revenue diversification; potential for additional products; and potential environmental impact. The study showed that techno-economic criteria are the most important barriers to the implementation of ethanol biorefineries. While thermochemical processes are economically feasible and provide greater flexibility, biochemical refining processes may provide for the development of other value-added products. 21 refs., 3 tabs., 7 figs.
[en] Ultrafast laser parallel microdrilling using diffractive multiple annular beam patterns is demonstrated in this paper. The annular beam was generated by diffractive axicon computer generated holograms (CGHs) using a spatial light modulator. The diameter of the annular beam can be easily adjusted by varying the radius of the smallest ring in the axicon. Multiple annular beams with arbitrary arrangement and multiple annular beam arrays were generated by superimposing an axicon CGH onto a grating and lenses algorithm calculated multi-beam CGH and a binary Dammann grating CGH, respectively. Microholes were drilled through a 0.03 mm thick stainless steel foil using the multiple annular beams. By avoiding huge laser output attenuation and mechanical annular scanning, the processing is ∼200 times faster than the normal single beam processing. (paper)
[en] In the last decade, indium tin oxide (ITO) has been most commonly employed to create transparent conducting oxides (TCOs) thin films for many industrial applications. It is usually necessary to pattern ITO thin films to create functional structures for specific applications. Direct-write micro-patterning of ITO thin films by ultra-short pulse lasers has demonstrated high quality without requiring multiple processing stations, compared with conventional patterning technologies (e.g. wet-etch lithography). However, the processing efficiency and throughput with a single beam can be insufficient because of the high level of attenuation needed for the output to meet the required ‘thermal-free’ parameters. In this paper, high throughput surface direct micro-structuring of ITO on glass is demonstrated by parallel processing using diffractive multiple ultrashort pulse laser beams (λ = 1064 nm, τp = 10 ps). By avoiding periodic and symmetrical geometry design, the diffractive multiple beam pattern generated by a spatial light modulator has high uniformity (the energy variation between each diffractive beam is <9%). The ITO thin film is removed by laser ablation of 25 identical beams at the same time without any damage to the glass substrate. Additionally, by synchronizing a scanning galvanometer, the processing demonstrates high flexibility to generate various surface patterns.
[en] La2-xBaxCuO4 (x=0.125 and x=0.115) was studied by x-ray diffraction at the O-K and the Cu-L3 resonances, in this way focussing on the O-2p and Cu-3d electronic structure. In both cases, pronounced charge-order superstructure peaks are observed directly below the temperature of the structural transition from the LTO into the LTT phase. This is in contrast to the case of La1.8-xEu0.2SrxCuO4, where charge order occurs at a lower temperature than the structural phase transition. Further differences between the materials are observed in the coherence lengths of the charge order, which is significantly larger in case of La2-xBaxCuO4. For the two resonances indications for a different evolution with temperature of the superstructure peaks in La2-xBaxCuO4 are found.
[en] Ultrafast laser parallel processing using diffractive multi-beam patterns generated by a spatial light modulator (SLM) has demonstrated a great increase in processing throughput and efficiency. Applications ranging from surface thin film patterning to internal 3D refractive index modification have been recently reported with the parallel processing technology. Periodic and symmetrical geometry design (e.g. N × M beam array) of the multi-beam pattern must be avoided to guarantee the required high uniformity in these applications, which, however, limited the processing flexibility. In this paper, Dammann gratings are used to create diffractive 1 × 5 and 5 × 5 beam arrays for the parallel processing. The 0-th order, observed slightly stronger than the other higher orders, can be adjusted by superimposing a Fresnel zone lens (FZL) and tuning the degree of defocusing at the processing plane. The uniformity (presented by the variation of the machined hole diameter) is measured to be <4% after the adjustment. Additionally, a parallel surface patterning of indium tin oxide (ITO) thin film with periodic array structures was demonstrated using the Dammann grating generated beam array without requiring the complicated geometry separation and the time-consuming positioning.
[en] A limit on developing new treatments for a number of central nervous system (CNS) disorders has been the inadequate understanding of the in vivo pathophysiology underlying neurological and psychiatric disorders and the lack of in vivo tools to determine brain penetrance, target engagement, and relevant molecular activity of novel drugs. Molecular neuroimaging provides the tools to address this. This article aims to provide a state-of-the-art review of new PET tracers for CNS targets, focusing on developments in the last 5 years for targets recently available for in-human imaging. We provide an overview of the criteria used to evaluate PET tracers. We then used the National Institute of Mental Health Research Priorities list to identify the key CNS targets. We conducted a PubMed search (search period 1st of January 2013 to 31st of December 2018), which yielded 40 new PET tracers across 16 CNS targets which met our selectivity criteria. For each tracer, we summarised the evidence of its properties and potential for use in studies of CNS pathophysiology and drug evaluation, including its target selectivity and affinity, inter and intra-subject variability, and pharmacokinetic parameters. We also consider its potential limitations and missing characterisation data, but not specific applications in drug development. Where multiple tracers were present for a target, we provide a comparison of their properties. Our review shows that multiple new tracers have been developed for proteinopathy targets, particularly tau, as well as the purinoceptor P2X7, phosphodiesterase enzyme PDE10A, and synaptic vesicle glycoprotein 2A (SV2A), amongst others. Some of the most promising of these include F-MK-6240 for tau imaging, C-UCB-J for imaging SV2A, C-CURB and C-MK-3168 for characterisation of fatty acid amide hydrolase, F-FIMX for metabotropic glutamate receptor 1, and F-MNI-444 for imaging adenosine 2A. Our review also identifies recurrent issues within the field. Many of the tracers discussed lack in vivo blocking data, reducing confidence in selectivity. Additionally, late-stage identification of substantial off-target sites for multiple tracers highlights incomplete pre-clinical characterisation prior to translation, as well as human disease state studies carried out without confirmation of test-retest reproducibility.
[en] Diamond detectors for radiation dosimetry were modelled using the EGSnrc Monte Carlo code to investigate the influence of electrode material and detector orientation on the absorbed dose. The small dimensions of the electrode/diamond/electrode detector structure required very thin voxels and the use of non-standard DOSXYZnrc Monte Carlo model parameters. The interface phenomena was investigated by simulating a 6 MV beam and detectors with different electrode materials, namely Al, Ag, Cu and Au, with thickens of 0.1 µm for the electrodes and 0.1 mm for the diamond, in both perpendicular and parallel detector orientation with regards to the incident beam. The smallest perturbations were observed for the parallel detector orientation and Al electrodes (Z = 13). In summary, EGSnrc Monte Carlo code is well suited for modelling small detector geometries. The Monte Carlo model developed is a useful tool to investigate the dosimetric effects caused by different electrode materials. To minimise perturbations cause by the detector electrodes, it is recommended that the electrodes should be made from a low-atomic number material and placed parallel to the beam direction.