Using first-principles fully kinetic simulations with a Fokker-Planck collision operator, it is demonstrated that Sweet-Parker reconnection layers are unstable to a chain of plasmoids (secondary islands) for Lundquist numbers beyond S >{approx} 1000. The instability is increasingly violent at higher Lundquist number, both in terms of the number of plasmoids produced and the super-Alfvenic growth rate. A dramatic enhancement in the reconnection rate is observed when the half-thickness of the current sheet between two plasmoids approaches the ion inertial length. During this transition, the reconnection electric field rapidly exceeds the runaway limit, resulting in the formation of electron-scale current layers that are unstable to the continual formation of new plasmoids.

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In this paper we present a trigger algorithm able to select online events enriched of b-jets. This feature is of central interest in order to extend the physics reach for standard model and minimal super symmetric model Higgs decaying into a pair of b-quarks. The algorithm fully exploits the recently upgraded CDFII tracking system and Level 2 CALorimeter cluster finder. These upgrades are necessary to cope with Tevatron increasing luminosity and provide new and refined trigger primitives that are the key elements of our algorithm together with the already existing silicon vertex trigger. A b-hadron can travel some millimeters before decaying and the trigger algorithm exploits this characteristic by searching for tracks displaced with respect to the primary vertex and matched to energetic jets of particles. We discuss the study and the optimization of the algorithm, its technical implementation as well as its performance. The new trigger provides an efficient selection for Higgs decaying into a pair of b-quarks and runs up to high luminosity with an acceptable occupancy of the available bandwidth.

The U.S. Department of Energy (DOE) amended the Record of Decision (ROD) for the Waste Management Program: Treatment and Storage ofTransuranic Waste to centralize transuranic (TRU) waste characterization/certification from fourteen TRU waste sites. This centralization will allow for treatment, characterization and certification ofTRU waste from the fourteen sites, thirteen of which are sites with small quantities ofTRU waste, at the Idaho National Laboratory (INL) prior to shipping the waste to the Waste Isolation Pilot Plant (WIPP) for disposal. Centralization ofthis TRU waste will avoid the cost ofbuilding treatment, characterization, certification, and shipping capabilities at each ofthe small quantity sites that currently do not have existing facilities. Advanced Mixed Waste Treatment Project (AMWTP) and Idaho Nuclear Technology and Engineering Center (INTEC) will provide centralized shipping facilities, to WIPP, for all ofthe small quantity sites. Hanford, the one large quantity site identified in the ROD, has a large number ofwaste in containers that are overpacked into larger containers which are inefficient for shipment to and disposal at WIPP. The AMWTP at the INL will reduce the volume ofmuch of the CH waste and make it much more efficient to ship and dispose of at WIPP. In addition, the INTEC has a certified …

Introduction to the special section on art history in the 2009 edition of The Eagle Feather.

We analyze pulsar fluxes at 1400 MHz (S(1400)) and distances d taken from the Australia National Telescope Facility (ATNF) Pulsar Catalogue. Under the assumption that pulsar populations in different parts of the Galaxy are similar, we find that either (a) pulsar fluxes diminish with distance according to a non-standard power law (we suggest S(1400){proportional_to} 1/d rather than {proportional_to} 1/d{sup 2}) or (b) that there are very significant (i.e. order of magnitude) errors in the distance estimates quoted in the ATNF Catalogue. The former conclusion (a) supports a recent model for pulsar emission that has also successfully explained the frequency spectrum of the Crab pulsar over 16 orders of magnitude of frequency, whilst alternative (b) would necessitate a radical re-evaluation of both the dispersion method for estimating pulsar distances and current ideas about the distribution of pulsars within our Galaxy.

Bis(imido) uranium(VI) trans- and cis-dichalcogenate complexes with the general formula U(NtBu)2(EAr)2(OPPh3)2 (EAr = O-2-tBuC6H4, SPh, SePh, TePh) and U(NtBu)2(EAr)2(R2bpy) (EAr = SPh, SePh, TePh) (R2bpy = 4,4'-disubstituted-2,2'-bipyridyl, R = Me, tBu) have been prepared. This family of complexes includes the first reported monodentate selenolate and tellurolate complexes of uranium(VI). Density functional theory calculations show that covalent interactions in the U-E bond increase in the trans-dichalcogenate series U(NtBu)2(EAr)2(OPPh3)2 as the size of the chalcogenate donor increases and that both 5f and 6d orbital participation is important in the M-E bonds of U-S, U-Se, and U-Te complexes.

US nuclear weapons capabilities -- extant force structure and nuclear weapons infrastructure as well as declared policy -- influence other nations' nuclear weapons postures, at least to some extent. This influence can be desirable or undesirable, and is, of course, a mixture of both. How strong the influence is, and its nature, are complicated, controversial, and -- in our view -- not well understood but often overstated. Divergent views about this influence and how it might shape the future global nuclear weapons regime seem to us to be the most serious impediment to reaching a national consensus on US weapons policy, force structure and supporting infrastructure. We believe that a paradigm shift to capability-based deterrence and dissuasion is not only consistent with the realities of the world and how it has changed, but also a desirable way for nuclear weapon postures and infrastructures to evolve. The US and other nuclear states could not get to zero nor even reduce nuclear arms and the nuclear profile much further without learning to manage latent capability. This paper has defined three principles for designing NW infrastructure both at the 'next plateau' and 'near zero.' The US can be a leader in reducing weapons …

We discuss a recent proposal to use strongly magnetized electron columns created by beam ionization of the residual gas for compensation of space charge forces of high intensity proton beams in synchrotrons and linacs. The electron columns formed by trapped ionization electrons in a longitudinal magnetic field that assures transverse distribution of electron space charge in the column is the same as in the proton beam. Electrostatic electrodes are used to control the accumulation and release of the electrons. Ions are not magnetized and drift away without affecting the compensation. Possible technical solution for the electron columns is presented. We also discuss the first numerical simulation results for space-charge compensation in the FNAL Booster and results of relevant beam studies in the Tevatron.

This article discusses a user-based channel assignment algorithm in a load-balanced IEEE 802.11 WLAN.

In certain types of 'slow burn' emergencies, careful accumulation and evaluation of information can offer a crucial advantage. The SARS outbreak in the first decade of the 21st century was such an event, and ad hoc journal clubs played a critical role in assisting scientific and technical responders in identifying and developing various strategies for halting what could have become a dangerous pandemic. This research-in-progress paper describes a process for leveraging emerging semantic web and digital library architectures and standards to (1) create a focused collection of bibliographic metadata, (2) extract semantic information, (3) convert it to the Resource Description Framework /Extensible Markup Language (RDF/XML), and (4) integrate it so that scientific and technical responders can share and explore critical information in the collections.

A modified form of the variational estimate of the reactivity worth ofa perturbation was previously developed to extend the range of applicability of variational perturbation theory for perturbations leading to negative reactivity worths. Recent numerical results challenged the assumptions behind the modified form. In this paper, more results are obtained, leading to the conclusion that sometimes the modified form extends the range ofapplicability of variational perturbation theory for positive reactivity worths as well, and sometimes the standard variational form is more accurate for negative-reactivity perturbations. In addition, this paper proves that using the exact generalized adjoint function would lead to an inaccurate variational reactivity estimate when the error in the first-order estimate is large; the standard generalized adjoint function, an approximation to the exact one, leads to Lore accurate results. This conclusion is also demonstrated numerically. Transport calculations use the PARTISN multi group discrete ordinates code

The exploration of the vertically integrated circuits, also commonly known as 3D-IC technology, for applications in radiation detection started at Fermilab in 2006. This paper examines the opportunities that vertical integration offers by looking at various 3D designs that have been completed by Fermilab. The emphasis is on opportunities that are presented by through silicon vias (TSV), wafer and circuit thinning and finally fusion bonding techniques to replace conventional bump bonding. Early work by Fermilab has led to an international consortium for the development of 3D-IC circuits for High Energy Physics. The consortium has submitted over 25 different designs for the Fermilab organized MPW run organized for the first time.

Article on examining technical quality and content and video-mediated communication in hospice interdisciplinary team meetings.

OnLine Analytical Processing (OLAP) is a relational database technology providing users with rapid access to summary, aggregated views of a single large database, and is widely recognized for knowledge representation and discovery in high-dimensional relational databases. OLAP technologies provide intuitive and graphical access to the massively complex set of possible summary views available in large relational (SQL) structured data repositories. The capability of OLAP database software systems to handle data complexity comes at a high price for analysts, presenting them a combinatorially vast space of views of a relational database. We respond to the need to deploy technologies sufficient to allow users to guide themselves to areas of local structure by casting the space of 'views' of an OLAP database as a combinatorial object of all projections and subsets, and 'view discovery' as an search process over that lattice. We equip the view lattice with statistical information theoretical measures sufficient to support a combinatorial optimization process. We outline 'hop-chaining' as a particular view discovery algorithm over this object, wherein users are guided across a permutation of the dimensions by searching for successive two-dimensional views, pushing seen dimensions into an increasingly large background filter in a 'spiraling' search process. We illustrate …

A new importance estimation technique has been developed that allows weight-window optimization for a linear combination of tallies. This technique has been implemented in a local version of MCNP and effectively weights the adjoint source term for each tally in the combination. Optimizing weight window parameters for the linear tally combination allows the user to optimize weight windows for multiple regions at once. In this work, we present our results of solutions to an analytic three-tally-region test problem and a flux calculation on a 100,000 voxel oil-well logging tool problem.

The rapid recognition and repair of DNA damage is essential for the maintenance of genomic integrity and cellular survival. Multiple complex and interconnected DNA damage responses exist within cells to preserve the human genome, and these repair pathways are carried out by a specifi c interplay of protein-protein interactions. Thus a failure in the coordination of these processes, perhaps brought about by a breakdown in any one multifunctional repair protein, can lead to genomic instability, developmental and immunological abnormalities, cancer and premature aging. This study demonstrates a novel interaction between two such repair proteins, Xeroderma pigmentosum group G protein (XPG) and Werner syndrome helicase (WRN), that are both highly pleiotropic and associated with inherited genetic disorders when mutated. XPG is a structure-specifi c endonuclease required for the repair of UV-damaged DNA by nucleotide excision repair (NER), and mutations in XPG result in the diseases Xeroderma pigmentosum (XP) and Cockayne syndrome (CS). A loss of XPG incision activity results in XP, whereas a loss of non-enzymatic function(s) of XPG causes CS. WRN is a multifunctional protein involved in double-strand break repair (DSBR), and consists of 3’–5’ DNA-dependent helicase, 3’–5’ exonuclease, and single-strand DNA annealing activities. Nonfunctional WRN protein leads to Werner …

This article focuses on the importance of contextualizing school policies by illuminating how one school rule, In-School-Suspension (ISS) disengages students from the learning process.

Office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv yr-! versus 0.3 mSv yr-!). The estimated effective dose rate for a more homebound person was about 3 mSv yr-!. …

This two-day workshop will engage the international neutron scattering community to vet and improve the Lujan Center Strategic Plan 2007-2013 (SP07). Sponsored by the LANL SC Program Office and the University of California, the workshop will be hosted by LANSCE Professor Sunny Sinha (UCSD). Endorsement by the Spallation Neutron Source will be requested. The discussion will focus on the role that the Lujan Center will play in the national neutron scattering landscape assuming full utilization of beamlines, a refurbished LANSCE, and a 1.4-MW SNS. Because the Lujan Strategic Plan is intended to set the stage for the Signature Facility era at LANSCE, there will be some discussion of the long-pulse spallation source at Los Alamos. Breakout groups will cover several new instrument concepts, upgrades to present instruments, expanded sample environment capabilities, and a look to the future. The workshop is in keeping with a request by BES to update the Lujan strategic plan in coordination with the SNS and the broader neutron community. Workshop invitees will be drawn from the LANSCE User Group and a broad cross section of the US, European, and Pacific Rim neutron scattering research communities.

The dislocation density and subgrain size were determined in the base material and friction-stir welds of 6061-T6 aluminum alloy. High-resolution X-ray diffraction measurement was performed in the base material. The result of the line profile analysis of the X-ray diffraction peak shows that the dislocation density is about 4.5 x 10{sup 14} m{sup 02} and the subgrain size is about 200 nm. Meanwhile, neutron diffraction measurements have been performed to observe the diffraction peaks during friction-stir welding (FSW). The deep penetration capability of the neutron enables us to measure the peaks from the midplane of the Al plate underneath the tool shoulder of the friction-stir welds. The peak broadening analysis result using the Williamson-Hall method shows the dislocation density of about 3.2 x 10{sup 15} m{sup -2} and subgrain size of about 160 nm. The significant increase of the dislocation density is likely due to the severe plastic deformation during FSW. This study provides an insight into understanding the transient behavior of the microstructure under severe thermomechanical deformation.

Paper examines perceptions of globalism among young Bolivians, aged 18-27, who are living in their home country, and how those opinions impact their perception of the new Bolivian constitution.

Article discussing a cross-cultural study designed to analyze how young people, operationalized in this study as people of Latino descent between the ages of 18-25, are using their mobile phone for various applications and what particular gratifications they derive from using the phone.