Prefrontal Neurons Coding Suppression of Specific Saccades

AbstractThe prefrontal cortex has been implicated in the suppression of unwanted behavior, based upon observations of humans and monkeys with prefrontal lesions. Despite this, there has been little direct neurophysiological evidence for a mechanism that suppresses specific behavior. In this study, we used an oculomotor delayed match/nonmatch-to-sample task in which monkeys had to remember a stimulus location either as a marker of where to look or as a marker of where not to look. We found a group of neurons in both the frontal eye field and the caudal prefrontal cortex that carried signals selective for the forbidden stimulus. The activity of these “don't look” neurons correlated with the monkeys' success or failure on the task. These results demonstrate a frontal signal that is related to the active suppression of one action while the subject performs another

A search for non-pulsating, chemically normal stars in the Scuti instability strip using Kepler data

We identify stars in the δ Sct instability strip that do not pulsate in p modes at the 50-μmag limit, using Kepler data. Spectral classification and abundance analyses from high-resolution spectroscopy allow us to identify chemically peculiar stars, in which the absence of pulsations is not surprising. The remaining stars are chemically normal, yet they are not δ Sct stars. Their lack of observed p modes cannot be explained through any known mechanism. However, they are mostly distributed around the edges of the δ Sct instability strip, which allows for the possibility that they actually lie outside the strip once the uncertainties are taken into account.We investigated the possibility that the non-pulsators inside the instability strip could be unresolved binary systems, having components that both lie outside the instability strip. If misinterpreted as single stars, we found that such binaries could generate temperature discrepancies of ∼300 K – larger than the spectroscopic uncertainties, and fully consistent with the observations. After these considerations, there remains one chemically normal nonpulsator that lies in the middle of the instability strip. This star is a challenge to pulsation theory. However, its existence as the only known star of its kind indicates that such stars are rare. We conclude that the δ Sct instability strip is pure, unless pulsation is shut down by diffusion or another mechanism, which could be interaction with a binary companion

Advanced Nuclear Power Systems to Mitigate Climate Change

Abstract Fossil fuels currently supply about 80% of humankind's primary energy. Given the imperatives of climate change, pollution, energy security and dwindling supplies, and enormous technical, logistical and economic challenges of scaling up coal or gas power plants with carbon capture and storage to sequester all that carbon, we are faced with the necessity of a nearly complete transformation of the world's energy systems. Objective analyses of the inherent constraints on wind, solar, and other less-mature renewable energy technologies inevitably demonstrate that they will fall far short of meeting today's energy demands, let alone the certain increased demands of the future. Nuclear power, however, is capable of providing all the carbon-free energy that mankind requires, although the prospect of such a massive deployment raises questions of uranium shortages, increased energy and environmental impacts from mining and fuel enrichment, and so on. These potential roadblocks can all be dispensed with, however, through the use of fast neutron reactors and fuel recycling. The Integral Fast Reactor (IFR), developed at U.S. national laboratories in the latter years of the last century, can economically and cleanly supply all the energy the world needs without any further mining or enrichment of uranium. Instead of utilizing a mere 0.6% of the potential energy in uranium, IFRs capture all of it. Capable of utilizing troublesome waste products already at hand, IFRs can solve the thorny spent fuel problem while powering the planet with carbon-free energy for nearly a millennium before any more uranium mining would even have to be considered. Designed from the outset for unparalleled safety and proliferation resistance, with all major features proven out at the engineering scale, this technology is unrivaled in its ability to solve the most difficult energy problems facing humanity in the 21 st century

Instances and connectors : issues for a second generation process language

This work is supported by UK EPSRC grants GR/L34433 and GR/L32699Over the past decade a variety of process languages have been defined, used and evaluated. It is now possible to consider second generation languages based on this experience. Rather than develop a second generation wish list this position paper explores two issues: instances and connectors. Instances relate to the relationship between a process model as a description and the, possibly multiple, enacting instances which are created from it. Connectors refers to the issue of concurrency control and achieving a higher level of abstraction in how parts of a model interact. We believe that these issues are key to developing systems which can effectively support business processes, and that they have not received sufficient attention within the process modelling community. Through exploring these issues we also illustrate our approach to designing a second generation process language.Postprin

A prospective cohort study of the impact of outpatient Intensive Cardiac Rehabilitation on depression and cardiac self-efficacy

STUDY OBJECTIVE: To evaluate whether an Intensive Cardiac Rehabilitation (ICR) program improves depression and cardiac self-efficacy among patients with a qualifying cardiac diagnosis. DESIGN: Prospective, longitudinal cohort design. SETTING: Single-center, tertiary referral, outpatient cardiac rehabilitation center. PARTICIPANTS: Patients with a qualifying diagnosis for ICR. INTERVENTIONS: Outpatient ICR. MAIN OUTCOME MEASURES: Mental health, as assessed using the Patient Health Questionnaire-9 (PHQ-9) and cardiac self-efficacy using the Cardiac Self-Efficacy (CSE) scale. RESULTS: Of the 268 patients included (median age 69 y, 73% men), 70% had no depressive symptoms at baseline (PHQ-9 score \u3c5). PHQ-9 scores improved in the overall sample (p \u3c 0.0001), with greater improvements among patients with mild depressive symptoms at baseline (-4 points, p \u3c 0.001) and those with moderate to severe depressive symptoms at baseline (-5.5 points, p \u3c 0.001). Cardiac self-efficacy improved overall, and the two subsections of the cardiac self-efficacy questionnaire titled, maintain function and control symptoms improved (all p \u3c 0.001). CONCLUSIONS: Participation in an outpatient ICR program is associated with fewer depressive symptoms and greater cardiac self-efficacy among patients with CVD who qualify for ICR. The improvement in depression was greatest for those with moderate to severe depressive symptoms

Preliminary Cruise Report, W0107A, R/V WECOMA, 6-8 July 2001, GLOBEC/ENSO Long-Term Observations off Oregon

PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along the Newport Hydro line, to make continuous bio-acoustic observations between the 50-500m. isobath, and to make continuous observations of currents using ADCP and of surfacelayer temperature, salinity and fluorescence by means of ship’s thru-flo system

Deeply virtual and exclusive electroproduction of omega mesons

The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q2) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t < 2.7 GeV2) to the proton. The contributions of the interference terms sigma_TT and sigma_TL to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi0 exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction gamma* p -> omega p, even for Q2 as large as 5 GeV2. Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behaviour of the cross sections is nearly Q2-independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit.Comment: 15 pages,19 figure

Preliminary Cruise Report, W0109A, R/V WECOMA, 4-10 September 2001 : GLOBEC NEP Long-Term Observations off Oregon

PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent City, CA.), to make continuous bio-acoustic observations between the 50-500m. isobaths along the 5 lines, to deploy drifters at selected locations on the Newport line, and to make continuous observations of currents using ADCP and of surface-layer temperature, salinity and fluorescence by means of ship’s thru-flo system

Preliminary Cruise Report, W0207A, R/V WECOMA, 9-15 July 2002 : GLOBEC NEP Long-Term Observations off Oregon

PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River, OR. and Crescent City, CA.), to make continuous bio-acoustic observations between the 50-500m. isobaths along the 5 lines, to deploy drifters at selected locations on the Newport line, and to make continuous observations of currents using ADCP and of surface-layer temperature, salinity and fluorescence by means of ship’s thru-flo system

Preliminary Cruise Report, NH 0307A, R/V NEW HORIZON, 2-8 July 2003 : GLOBEC NEP Long-Term Observations off Oregon

PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along 4 lines (off Newport, Heceta Head, Coos Bay, OR. and Crescent City, CA.), to deploy drifters at selected locations on the Newport line, and to make continuous observations of currents using ADCP and of surface-layer temperature, salinity and fluorescence by means of ship’s thru-flo system