Real-time Artificial Intelligence for Accelerator Control: A Study at the Fermilab Booster

We describe a method for precisely regulating the gradient magnet power supply at the Fermilab Booster accelerator complex using a neural network trained via reinforcement learning. We demonstrate preliminary results by training a surrogate machine-learning model on real accelerator data to emulate the Booster environment, and using this surrogate model in turn to train the neural network for its regulation task. We additionally show how the neural networks to be deployed for control purposes may be compiled to execute on field-programmable gate arrays. This capability is important for operational stability in complicated environments such as an accelerator facility.Comment: 16 pages, 10 figures. Submitted to Physical Review Accelerators and Beams. For associated dataset and data sheet see http://doi.org/10.5281/zenodo.408898

Sources and distribution of organic matter in northern Patagonia fjords, Chile (~44–47° S) : a multi–tracer approach for carbon cycling assessment

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 31 (2011): 315-329, doi:10.1016/j.csr.2010.05.013.We investigated the provenance of organic matter in the inner fjord area of northern Patagonia, Chile (~44–47° S), by studying the elemental (organic carbon, total nitrogen), isotopic (δ13C, δ15N), and biomarker (n–alkanoic acids from vascular plant waxes) composition of surface sediments as well as local marine and terrestrial organic matter. Average end–member values of N/C, δ13C, and δ15N from organic matter were 0.127 ± 0.010, –19.8 ± 0.3‰, and 9.9 ± 0.5‰ for autochthonous (marine) sources and 0.040 ± 0.018, –29.3 ± 2.1‰, 0.2 ± 3.0‰ for allochthonous (terrestrial) sources. Using a mixing equation based on these two end–members, we calculated the relative contribution of marine and terrestrial organic carbon from the open ocean to the heads of fjords close to river outlets. The input of marine–derived organic carbon varied widely and accounted for 13 to 96% (average 61%) of the organic carbon pool of surface sediments. Integrated regional calculations for the inner fjord system of northern Patagonia, which encompasses an area of ~ 4,280 km2, suggest that carbon accumulation may account for between 2.3 and 7.8 x 104 ton C yr–1. This represents a storage capacity of marine–derived carbon between 1.8 and 6.2 x 104 tons yr–1, which corresponds to an assimilation rate of CO2 by marine photosynthesis between 0.06 and 0.23 x 106 tons yr–1. This rate suggests that the entire fjord system of Patagonia, which covers an area of ~ 240,000 km2, may represent a potentially important region for the global burial of marine organic matter and the sequestration of atmospheric CO2.J. Sepúlveda was funded by a M.S. scholarship from the Graduate School at UDEC and by Fundación Andes through the Woods Hole Oceanographic Institution (WHOI)/UDEC agreement during a research visit at WHOI. This research was funded by the Ministerio de Hacienda de Chile and the Comité Oceanográfico Nacional (CONA) through the CIMAR–7 FIORDO Program (Grant C7F 01–10 to SP), CONICYT/NSF Grant 2001–120, Fundación Andes–Chile, and the Center for Oceanographic Research in the eastern South Pacific (COPAS) and COPAS Sur– Austral (PFB–31/2007)

Australia's National Bowel Cancer Screening Program: does it work for Indigenous Australians?

<p>Abstract</p> <p>Background</p> <p>Despite a lower incidence of bowel cancer overall, Indigenous Australians are more likely to be diagnosed at an advanced stage when prognosis is poor. Bowel cancer screening is an effective means of reducing incidence and mortality from bowel cancer through early identification and prompt treatment. In 2006, Australia began rolling out a population-based National Bowel Cancer Screening Program (NBCSP) using the Faecal Occult Blood Test. Initial evaluation of the program revealed substantial disparities in bowel cancer screening uptake with Indigenous Australians significantly less likely to participate in screening than the non-Indigenous population.</p> <p>This paper critically reviews characteristics of the program which may contribute to the discrepancy in screening uptake, and includes an analysis of organisational, structural, and socio-cultural barriers that play a part in the poorer participation of Indigenous and other disadvantaged and minority groups.</p> <p>Methods</p> <p>A search was undertaken of peer-reviewed journal articles, government reports, and other grey literature using electronic databases and citation snowballing. Articles were critically evaluated for relevance to themes that addressed the research questions.</p> <p>Results</p> <p>The NBCSP is not reaching many Indigenous Australians in the target group, with factors contributing to sub-optimal participation including how participants are selected, the way the screening kit is distributed, the nature of the test and comprehensiveness of its contents, cultural perceptions of cancer and prevailing low levels of knowledge and awareness of bowel cancer and the importance of screening.</p> <p>Conclusions</p> <p>Our findings suggest that the population-based approach to implementing bowel cancer screening to the Australian population unintentionally excludes vulnerable minorities, particularly Indigenous and other culturally and linguistically diverse groups. This potentially contributes to exacerbating the already widening disparities in cancer outcomes that exist among Indigenous Australians. Modifications to the program are recommended to facilitate access and participation by Indigenous and other minority populations. Further research is also needed to understand the needs and social and cultural sensitivities of these groups around cancer screening and inform alternative approaches to bowel cancer screening.</p

Positioning of chest tubes: effects on pressure and drainage

BACKGROUND: Maintaining a chest drainage tube in a position that is free of dependent loops, as is commonly recommended, can be very difficult. Is there a beneficial effect on the patient's outcome when the drainage tubing is free of dependent loops? OBJECTIVE: The purpose of this study was to determine, under controlled laboratory conditions, (1) what are the differences in drainage with tubing in straight, coiled, or dependent-loop (with and without periodic lifting) positions and (2) what are the differences in pressure with each of the four tubing conditions? METHODS: In laboratory simulations, pressure and drainage were observed in a chest tube drainage system that was connected to a glass bottle simulating the lung. Pressure and drainage were measured for 1 hour with the drainage tubing placed in straight, coiled, and dependent-loop positions. For the periodic lifting condition, the dependent loop was lifted and drained every 15 minutes. RESULTS: We found no differences in pressure or drainage between straight and coiled positions of the drainage tubing. However, with the dependent-loop position, pressure at the "lung" side increased from about -18 cm H2O to as high as +8 cm H2O. Drainage dropped to zero without tube lifting. When the tube was lifted and drained every 15 minutes, there was no difference in drainage with the tubing in the straight or coiled positions. CONCLUSION: Findings support recommendations to maintain tubing free of dependent loops by placing tubing in straight or coiled positions. Frequently lifting and draining a dependent loop will provide the same total drainage amount as maintaining the tubing in a straight or coiled position, but pressures may be altered sufficiently within the tube to exceed recommended levels.</jats:p

Patients' perceptions and responses to procedural pain: results from Thunder Project II

BACKGROUND: Little is known about the painfulness of procedures commonly performed in acute and critical care settings. OBJECTIVE: To describe pain associated with turning, wound drain removal, tracheal suctioning, femoral catheter removal, placement of a central venous catheter, and nonburn wound dressing change and frequency of use of analgesics during procedures. METHODS: A comparative, descriptive design was used. Numeric rating scales were used to measure pain intensity and procedural distress; word lists, to measure pain quality. RESULTS: Data were obtained from 6201 patients: 176 younger than 18 years and 5957 adults. Mean pain intensity scores for turning and tracheal suctioning were 2.80 and 3.00, respectively (scale, 0-5), for 4- to 7-year-olds and 52.0 and 28.1 (scale, 0-100) for 8- to 12-year-olds. For adolescents, mean pain intensity scores for wound dressing change, turning, tracheal suctioning, and wound drain removal were 5 to 7 (scale, 0-10); mean procedural distress scores were 4.83 to 6.00 (scale, 0-10). In adults, mean pain intensity scores for all procedures were 2.65 to 4.93 (scale, 0-10); mean procedural distress scores were 1.89 to 3.47 (scale, 0-10). The most painful and distressing procedures were turning for adults and wound care for adolescents. Procedural pain was often described as sharp, stinging, stabbing, shooting, and awful. Less than 20% of patients received opiates before procedures. CONCLUSIONS: Procedural pain varies considerably and is procedure specific. Because procedures are performed so often, more individualized attention to preparation for and control of procedural pain is warranted.</jats:p