Estimation of epicardial electrical potentials from body surface measurements based on a digital simulation of the human theory

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Information Shocks, Jumps, and Price Discovery -- Evidence from the U.S. Treasury Market

We examine large price changes, known as jumps, in the U.S. Treasury market. Using recently developed statistical tools, we identify price jumps in the 2-, 3-, 5-, 10-year notes and 30-year bond during the period of 2005-2006. Our results show that jumps mostly occur during prescheduled macroeconomic announcements or events. Nevertheless, market surprise based on preannouncement surveys is an imperfect predictor of bond price jumps. We find that a macroeconomic news announcement is often preceeded by an increase in market volatility and a withdrawal of liquidity, and that liquidity shocks play an important role for price jumps in U.S. Treasury market. More importantly, we present evidence that jumps serve as a dramatic form of price discovery in the sense that they help to quickly incorporate market information into bond prices.Financial markets

Development of an intelligent hypertext manual for the space shuttle hazardous gas detection system

A computer-based Integrated Knowledge System (IKS), the Intelligent Hypertext Manual (IHM), is being developed for the Space Shuttle Hazardous Gas Detection System (HGDS) at the Huntsville Operations Support Center (HOSC). The IHM stores all HGDS related knowledge and presents them in an interactive and intuitive manner. The IHM's purpose is to provide HGDS personnel with the capabilities of: enhancing the interpretation of real time data; recognizing and identifying possible faults in the Space Shuttle sub-system related to hazardous gas detections; locating applicable documentation related to procedures, constraints, and previous fault histories; and assisting in the training of personnel

Private Information Flow and Price Discovery in the U.S. Treasury Market

Existing studies show that U.S. Treasury bond price changes are mainly driven by public information shocks, as manifested in macroeconomic news announcements and events. The literature also shows that heterogeneous private information contributes significantly to price discovery for U.S. Treasury securities. In this paper, we use high frequency transaction data for 2-, 5-, and 10-year Treasury notes and employ a Markov switching model to identify intraday private information flow in the U.S. Treasury market. We show that the probability of private information flow (PPIF) identified in our model effectively captures permanent price effects in U.S. Treasury securities. In addition, our results show that public information shocks and heterogeneous private information are the main factors of bond price discovery on announcement days, whereas private information and liquidity shocks play more important roles in bond price variation on non-announcement days. Most interestingly, our results show that the role of heterogeneous private information is more prominent when public information shocks are either high or low. Furthermore, we show that heterogeneous private information flow is followed by low trading volume, low total market depth and hidden depth. The pattern is more pronounced on non-announcement days.Financial markets; Market structure and pricing

Quad-Tree Visual-Calculus Analysis of Satellite Coverage

An improved method of analysis of coverage of areas of the Earth by a constellation of radio-communication or scientific-observation satellites has been developed. This method is intended to supplant an older method in which the global-coverage-analysis problem is solved from a ground-to-satellite perspective. The present method provides for rapid and efficient analysis. This method is derived from a satellite-to-ground perspective and involves a unique combination of two techniques for multiresolution representation of map features on the surface of a sphere

Phase I dose-escalation and pharmacokinetic study of dasatinib in patients with advanced solid tumors

PURPOSE: To determine the maximum tolerated dose, dose-limiting toxicity (DLT), and recommended phase II dose of dasatinib in metastatic solid tumors refractory to standard therapies or for which no effective standard therapy exists. <br></br> EXPERIMENTAL DESIGN: In this phase I, open-label, dose-escalation study, patients received 35 to 160 mg of dasatinib twice daily in 28-day cycles either every 12 hours for 5 consecutive days followed by 2 nontreatment days every week (5D2) or as continuous, twice-daily (CDD) dosing. <br></br> RESULTS: Sixty-seven patients were treated (5D2, n = 33; CDD, n = 34). The maximum tolerated doses were 120 mg twice daily 5D2 and 70 mg twice daily CDD. DLTs with 160 mg 5D2 were recurrent grade 2 rash, grade 3 lethargy, and one patient with both grade 3 prolonged bleeding time and grade 3 hypocalcemia; DLTs with 120 mg twice daily CDD were grade 3 nausea, grade 3 fatigue, and one patient with both grade 3 rash and grade 2 proteinuria. The most frequent treatment-related toxicities across all doses were nausea, fatigue, lethargy, anorexia, proteinuria, and diarrhea, with infrequent hematologic toxicities. Pharmacokinetic data indicated rapid absorption, dose proportionality, and lack of drug accumulation. Although no objective tumor responses were seen, durable stable disease was observed in 16% of patients.<br></br> CONCLUSION: Dasatinib was well tolerated in this population, with a safety profile similar to that observed previously in leukemia patients, although with much less hematologic toxicity. Limited, although encouraging, preliminary evidence of clinical activity was observed. Doses of 120 mg twice daily (5D2) or 70 mg twice daily (CDD) are recommended for further studies in patients with solid tumors.<br></br&gt

The effect of pre-procedure sublingual nitroglycerin on radial artery diameter and Allen’s test outcome - relevance to transradial catheterization

Background The radial artery is increasingly used for cardiac procedures, but is a relatively small vessel that is prone to spasm when instrumented. Intra-arterial nitroglycerine has been shown to reduce radial spasm but first requires arterial access. We investigated the effect of pre-procedure sublingual nitroglycerin (NTG) on the diameter of the radial artery in a large cohort of patients. Methods 305 subjects underwent ultrasound measurement of their radial and ulnar arteries in both arms before and after the administration of 800 μg of sublingual NTG. The Allen's test was also performed in the subjects prior to and after NTG. Results Radial artery diameter in this Caucasian study group is larger than that reported for other populations. The administration of sublingual NTG significantly increased the size of the right radial artery from 2.88 ± 0.36 mm to 3.36 ± 0.40 mm in men and from 2.23 ± 0.37 up to 2.74 ± 0.36 mm in women. There were also significant increases in left radial, right and left ulnar artery diameters in males and females with NTG. There was no significant effect of NTG on blood pressure. In all patients with an unfavourable Allen's test, retesting following sublingual NTG resulted in transition to a favourable Allen's. Conclusion Caucasian populations have larger calibre radial arteries compared to other geographic areas. Sublingual NTG is effective at dilating the radial artery in both men and women. This may make radial artery puncture and cannulation less challenging and should be considered in all patients in the absence of contraindications. The results of Allen's testing are dynamic and its usefulness for screening prior to transradial access is undetermined

Ultrastructural Modification of the Plasma Membrane in HUT 102 Lymphoblasts by Long-Wave Ultraviolet Light, Psoralen, and PUVA

Ultrastructural alterations of the plasma membrane in HUT 102 lymphoblasts were assessed after a 2-h interaction with a suprapharmacologic (15 μ/m1) concentration of 8-MOP, 2-h irradiation with UVA (2.1 mW/cm2), and the exposure of the HUT 102 cells to PUVA under the same conditions.The dark reaction of HUT cells with 8-MOP resulted in the disappearance of microvilli, the emergence of plasma-membrane-associated spherical bodies, formation of lamellar fungiform membrane evaginations, and, in approximately 1% of the cells, formation of uropods and cell capping. Except for uropod formation and cell capping, UVA has induced the same plasma-membrane alterations, and was more deleterious to structural cytoplasmic integrity than 8-MOP. Morphologic changes of the plasma membrane in PUVA- exposed cells tended to replicate structural alterations elicited independently during the dark reaction by suprapharmacologic 8-MOP concentrations. Partial retention of microvilli by cells after PUVA was the sole exception.In light of all available evidence we conclude that psoralen during the dark reactions interacts with plasma membrane lipids by as yet undisclosed mechanisms and that in addition to lipids, membrane proteins are also the primary target of the initial interaction of HUT 102 cells with psoralen during PUVA treatment

All-optical mapping of barrel cortex circuits based on simultaneous voltage-sensitive dye imaging and channelrhodopsin-mediated photostimulation

© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Neurophotonics 2 (2015): 021013, doi:10.1117/1.NPh.2.2.021013.We describe an experimental approach that uses light to both control and detect neuronal activity in mouse barrel cortex slices: blue light patterned by a digital micromirror array system allowed us to photostimulate specific layers and columns, while a red-shifted voltage-sensitive dye was used to map out large-scale circuit activity. We demonstrate that such all-optical mapping can interrogate various circuits in somatosensory cortex by sequentially activating different layers and columns. Further, mapping in slices from whisker-deprived mice demonstrated that chronic sensory deprivation did not significantly alter feedforward inhibition driven by layer 5 pyramidal neurons. Further development of voltage-sensitive optical probes should allow this all-optical mapping approach to become an important and high-throughput tool for mapping circuit interactions in the brain.This work was supported by the World Class Institute (WCI) program of the National Research Foundation of Korea (NRF) funded by Ministry of Education, Science and Technology of Korea (MEST) (NRF) Grant No. WCI 2009-003 and by the Competitive Research Programme (CRP) of NRF (Singapore) Grant No. NRF 2008 NRF-CRP 002-082

Electrical activation and electron spin resonance measurements of implanted bismuth in isotopically enriched silicon-28

We have performed continuous wave and pulsed electron spin resonance measurements of implanted bismuth donors in isotopically enriched silicon-28. Donors are electrically activated via thermal annealing with minimal diffusion. Damage from bismuth ion implantation is repaired during thermal annealing as evidenced by narrow spin resonance linewidths (B_pp=12uT and long spin coherence times T_2=0.7ms, at temperature T=8K). The results qualify ion implanted bismuth as a promising candidate for spin qubit integration in silicon.Comment: 4 pages, 4 figure