Tokamak engineering test reactor

The design criteria for a tokamak engineering test reactor can be met by operating in the two-component mode with reacting ion beams, together with a new blanket-shield design based on internal neutron spectrum shaping. A conceptual reactor design achieving a neutron wall loading of about 1 MW/m$sup 2$ is presented. The tokamak has a major radius of 3.05 m, the plasma cross-section is noncircular with a 2:1 elongation, and the plasma radius in the midplane is 55 cm. The total wall area is 149 m$sup 2$. The plasma conditions are T/sub e/ approximately T/sub i/ approximately 5 keV, and ntau approximately 8 x 10$sup 12$ cm$sup -3$s. The plasma temperature is maintained by injection of 177 MW of 200- keV neutral deuterium beams; the resulting deuterons undergo fusion reactions with the triton-target ions. The D-shaped toroidal field coils are extended out to large major radius (7.0 m), so that the blanket-shield test modules on the outer portion of the torus can be easily removed. The TF coils are superconducting, using a cryogenically stable TiNb design that permits a field at the coil of 80 kG and an axial field of 38 kG. The blanket-shield design for the inner portion of the torus nearest the machine center line utilizes a neutron spectral shifter so that the first structural wall behind the spectral shifter zone can withstand radiation damage for the reactor lifetime. The energy attenuation in this inner blanket is 8 x 10$sup -6$. If necessary, a tritium breeding ratio of 0.8 can be achieved using liquid lithium cooling in the outer blanket only. The overall power consumption of the reactor is about 340 MW(e). A neutron wall loading greater than 1 MW/m$sup 2$ can be achieved by increasing the maximum magnetic field or the plasma elongation. (auth

AAOmega spectroscopy of 29 351 stars in fields centered on ten Galactic globular clusters

Galactic globular clusters have been pivotal in our understanding of many astrophysical phenomena. Here we publish the extracted stellar parameters from a recent large spectroscopic survey of ten globular clusters. A brief review of the project is also presented. Stellar parameters have been extracted from individual stellar spectra using both a modified version of the Radial Velocity Experiment (RAVE) pipeline and a pipeline based on the parameter estimation method of RAVE. We publish here all parameters extracted from both pipelines. We calibrate the metallicity and convert this to [Fe/H] for each star and, furthermore, we compare the velocities and velocity dispersions of the Galactic stars in each field to the Besan\c{c}on Galaxy model. We find that the model does not correspond well with the data, indicating that the model is probably of little use for comparisons with pencil beam survey data such as this.Comment: 6 pages, 5 figures, 4 tables. Accepted for publication in A&A. Data described in tables will be available on CDS (at http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/530/A31) once publishe

The SUMO Ligase Protein Inhibitor of Activated STAT 1 (PIAS1) is a constituent PML-NB protein that contributes to the intrinsic antiviral immune response to herpes simplex virus 1 (HSV-1)

Aspects of intrinsic antiviral immunity are mediated by promyelocytic leukaemia (PML)-nuclear body (PML-NB) constituent proteins. During herpesvirus infection, these antiviral proteins are independently recruited to nuclear domains that contain infecting viral genomes to cooperatively promote viral genome silencing. Central to the execution of this particular antiviral response is the small ubiquitin-like modifier (SUMO) signalling pathway. However, the participating SUMOylation enzymes are not fully characterized. We identify the SUMO ligase Protein Inhibitor of Activated STAT1 (PIAS1) as a constituent PML-NB protein. We show that PIAS1 localizes at PML-NBs in a SUMO interaction motif (SIM)-dependent manner that requires SUMOylated or SUMOylation competent PML. Following infection with herpes simplex virus 1 (HSV-1), PIAS1 is recruited to nuclear sites associated with viral genome entry in a SIM-dependent manner, consistent with the SIM-dependent recruitment mechanisms of other well characterized PML-NB proteins. In contrast to Daxx and Sp100, however, the recruitment of PIAS1 is enhanced by PML. PIAS1 promotes the stable accumulation of SUMO1 at nuclear sites associated with HSV-1 genome entry, whereas the accumulation of other evaluated PML-NB proteins occurs independently of PIAS1. We show that PIAS1 cooperatively contributes to HSV-1 restriction through mechanisms that are additive to those of PML and cooperative with those of PIAS4. The antiviral mechanisms of PIAS1 are counteracted by ICP0, the HSV-1 SUMO-targeted ubiquitin ligase, which disrupts the recruitment of PIAS1 to nuclear domains that contain infecting HSV-1 genomes through mechanisms that do not directly result in PIAS1 degradation

Monellin (MNEI) at 1.15 Å resolution

The crystal structure of the sweet protein MNEI at 1.15 Å resolution reveals networks of alternate conformations and stably bound negative ions

Mudstone characterization and classification at a proposed hub scale carbon sequestration complex: Kemper County, Mississippi, United States

The Mississippi Embayment in the US gulf coast plain and adjacent continental shelf present a vast resource for anthropogenic carbon capture and sequestration (CCS) opportunities from point sources to hub scale sequestration projects and are likely to be the site of many sequestration facilities in the coming decades. The current need to sequester anthropogenic CO2 is no less than a thousand-fold of the current sequestration projects and saline reservoirs are a major target for injection operations both on and offshore. The Cretaceous and Tertiary strata within east-central Mississippi are proven to be world-class reservoirs, and have been characterized through the DOE CarbonSAFE Phase II (2017) and Phase III (2020) program and the drilling of 6 exploration wells. The drilling program and associated data led to a high-resolution stratigraphic delineation, reservoir and confinement characterization, and mudstone baffles, barriers, and seals classification of a 1.4 Gt resource within stacked reservoirs of multistory aggraded sandstone with a geometric mean permeability of 3.6 Darcy. The primary, secondary, and auxiliary reservoirs are the Paluxy Formation (Albian), Washita-Fredericksburg interval (Albian), and Lower Tuscaloosa Massive sand (Cenomanian) that internally contain mudstone baffles that are relatively thin and discontinuous through offset wells and the area of review and define reservoir heterogeneity. Thickly bedded aggraded paleosol deposits in the basal and upper Washita-Fredericksburg interval act as barriers to fluid flow and facilitate vertical plume confinement within the primary and secondary reservoirs. If fugitive CO2 is to vertically escape out of the designated reservoirs the Lower Tuscaloosa sand will act as a storage buffer while also preventing significant CO₂ impingement at the reservoirs and seal interface. The major confining unit to the sequestration complex is the Marine Tuscaloosa shale (Cenomanian) that is clay rich and interpreted to have internal clinoform bedding morphology and was deposited as part of a eustatic rise in base level. The mudstone barriers and Marine Tuscaloosa seal have an absolute permeability on the order of 10-100 nD are regionally present, laterally continuous, and have implicit confinement to prevent significant amounts of CO₂ from escaping the designated sequestration reservoirs and contaminating the USDW in the Naheola and Nanafalia Formations

Soluble Trace Elements and Total Mercury in Arctic Alaskan Snow

Ultraclean field and laboratory procedures were used to examine trace element concentrations in northern Alaskan snow. Sixteen soluble trace elements and total mercury were determined in snow core samples representing the annual snowfall deposited during the 1993-94 season at two sites in the Prudhoe Bay oil field and nine sites in the Arctic National Wildlife Refuge (Arctic NWR). Results indicate there were two distinct point sources for trace elements in the Prudhoe Bay oil field- a source associated with oil and gas production and a source associated with municipal solid-waste incineration. Soluble trace element concentrations measured in snow from the Arctic NWR resembled concentrations of trace elements measured elsewhere in the Arctic using clean sample-collection and processing techniques and were consistent with deposition resulting from widespread arctic atmospheric contamination. With the exception of elements associated with sea salts, there were no orographic or east-west trends observed in the Arctic NWR data, nor were there any detectable influences from the Prudhoe Bay oil field, probably because of the predominant easterly and northeasterly winds on the North Slope of Alaska. However, regression analysis on latitude suggested significant south-to-north increases in selected trace element concentrations, many of which appear unrelated to the sea salt contribution.Des techniques ultra-propres utilisées sur le terrain et en laboratoire ont permis d'étudier les concentrations en éléments traces dans la neige de l'Alaska septentrional. Seize éléments traces solubles et le mercure total ont été mesurés dans des carottes de neige représentant la chute nivale annuelle de la saison 1993-94 à deux emplacements du champ pétrolifère de Prudhoe Bay et à neuf emplacements du refuge faunique national Arctique. Les résultats révèlent qu'il existe deux sources ponctuelles distinctes d'éléments traces découverts dans le champ pétrolifère de Prudhoe Bay, l'une reliée à la production de pétrole et de gaz et l'autre reliée à l'incinération des déchets municipaux solides. Les concentrations en éléments traces solubles mesurées dans la neige du refuge faunique national Arctique s'apparentaient aux concentrations en éléments traces mesurées ailleurs dans l'Arctique à l'aide de techniques propres de prélèvement et de traitement des carottes. Ces concentrations correspondent bien à des dépôts engendrés par une pollution atmosphérique généralisée dans l'Arctique. À l'exception des éléments associés aux sels marins, on n'a observé aucune tendance orographique ou est-ouest dans les données du refuge faunique national Arctique, de même qu'on n'a pas décelé d'influences perceptibles dues au champ pétrolifère de Prudhoe Bay, probablement en raison des vents prédominants d'est et du nord-est sur le versant nord de l'Alaska. L'analyse de régression sur la latitude suggère cependant une augmentation importante en allant du sud au nord dans les concentrations en certains éléments traces, dont beaucoup ne semblent pas reliées à l'apport de sel marin

Workshop report: Workshop on psychiatric prescribing and psychology testing and intervention in children and adults with Duchenne muscular dystrophy

This workshop aimed at summarising knowledge and key issues in psychiatric prescribing and psychological testing in children and adults with Duchenne muscular dystrophy (DMD). It comprised clinicians and patient representatives from the UK and the Netherlands. The following topics were discussed: a model for capturing the range of non-motor problems in the domains of cognition, learning, emotion and behaviour; psychosocial screening tools for use with children and adults; assessing neurocognitive functioning in children and adults; parent and teacher perspectives on psychosocial needs; and psychopharmacological treatment for affective disorders, anxiety disorders, obsessive compulsive disorder, attention deficit hyperactivity disorder (ADHD) and insomnia. Some key considerations included: the need for tools used to assess behavioural and psychosocial functioning to consider motor aspects in DMD; to understand more about working memory performance; the need for early interventions for automatisation problems, which affect reading and arithmetic; appropriate selection of tests for neuropsychology assessments; in schools, acknowledging the range of psychosocial risks and gathering evidence of psychosocial needs; the suitability of selective serotonin reuptake inhibitors for mood and anxiety disorders; the use of stimulant medications for ADHD; melatonin use for insomnia; the cautious use of benzodiazepines; and the need for improving pathways for psychosocial care

Mirror-Descent Methods in Mixed-Integer Convex Optimization

In this paper, we address the problem of minimizing a convex function f over a convex set, with the extra constraint that some variables must be integer. This problem, even when f is a piecewise linear function, is NP-hard. We study an algorithmic approach to this problem, postponing its hardness to the realization of an oracle. If this oracle can be realized in polynomial time, then the problem can be solved in polynomial time as well. For problems with two integer variables, we show that the oracle can be implemented efficiently, that is, in O(ln(B)) approximate minimizations of f over the continuous variables, where B is a known bound on the absolute value of the integer variables.Our algorithm can be adapted to find the second best point of a purely integer convex optimization problem in two dimensions, and more generally its k-th best point. This observation allows us to formulate a finite-time algorithm for mixed-integer convex optimization