5,731 research outputs found
Acoustic emission and sonoluminescence due to cavitation at the beam focus of an electrohydraulic shock wave lithotripter
No full textThe acoustic emission from cavitation in the field of an extracorporeal shock wave lithotripter has been studied using a lead zirconate titanate piezoceramic (PC4) hydrophone in the form of a 100-mm diameter focused bowl of 120-mm focal length. With this hydrophone directed at the beam focus of an electrohydraulic lithotripter radiating into water, it is possible to identify signals well above the noise level, at the 1-MHz resonance of the hydrophone, which originate at the beam focus. Light emission, attributed to sonoluminescence, is also shown to originate at the focal region of the lithotripter, and the signal obtained from a fast photomultiplier tube directed at the focus has similarities in structure and timing to the detected acoustic signals. The multiple shock emission resulting from a single discharge of an electrohydraulic source is shown to result in two separate bursts of cavitational activity separated by a period of 3-4 ms. The signal burst corresponding to the primary shock has a duration of about 600 us with little noticeable structure. The signal burst associated with the secondary shock has a reproducible structure with two distinct peaks separated by about ~200 us depending on the shock amplitude. The timing and structure of each burst is shown to be in reasonable agreement with the theoretical predictions made by Church (1989) based on the Gilmore model of bubble dynamics. In particular, it is shown that it is possible to obtain precise measurements of the time delay between the separate peaks within the signal burst detected following the secondary shock and this may, as predicted, provide a method of determining the size of bubbles remaining after the primary shock
Role Of Partial Transpose And Generalized Choi Maps In Quantum Dynamical Semigroups Involving Separable And Entangled States
No full textPower symmetric stochastic matrices introduced by R. Sinkhorn (1981) and their generalization by R.B. Bapat, S.K. Jain and K. Manjunatha Prasad (1999) have been utilized to give positive block matrices with trace one possessing positive partial transpose, the so-called PPT states. Another method to construct such PPT states is given, it uses the form of a matrix unitarily equivalent to to its transpose obtained by S.R. Garcia and J.E. Tener (2012). Evolvement or suppression of separability or entanglement of various levels for a quantum dynamical semigroup of completely positive maps has been studied using Choi-Jamiolkowsky matrix of such maps and the famous Hordeckis criteria (1996). A Trichotomy Theorem has been proved, and examples have been given that depend mainly on generalized Choi maps and clearly distinguish the levels of entanglement breaking
Figures 1–6 in Occurrence status of the fall armyworm (Lepidoptera: Noctuidae) in South Korea
No full textFigures 1–6. Three species of Spodoptera moths. 1) Funnel trap baited with pheromone for fall armyworm. 2–3) Spodoptera frugiperda (J.E. Smith) male captured in surveillance traps and genitalia. 4) Spodoptera frugiperda (J.E. Smith), male. 5) Spodoptera exigua (Hübner), male. 6) Spodoptera litura (Fabricius), male.Published as part of Suh, Soo-Jung, Choi, Deuk-Soo, Sol-moon & Na, 2021, Occurrence status of the fall armyworm (Lepidoptera: Noctuidae) in South Korea, pp. 1-5 in Insecta Mundi 2021 (850) on page 3, DOI: 10.5281/zenodo.504150
Polymorphism near the IL28B gene in Korean hepatitis C virus-infected patients treated with peg-interferon plus ribavirin
No full textBackground: Single nucleotide polymorphisms (SNPs) near the IL28B gene have recently been described as predictors of antiviral therapy responses in patients with hepatitis C virus (HCV) genotype-1. Objectives: The aim of this study was to investigate the association between genetic variation near the IL28B gene and treatment outcome prediction in Korean patients receiving peg-interferon (PEG-IFN) plus ribavirin therapy. Study design: The allelic discrimination assay by Taqman real-time PCR was developed to determine genotypes of SNPs, rs12979860 and rs8099917, which were analyzed in 65 Korean patients with HCV genotype-1. Results: For rs12979860, the frequency of patients with sustained virological response (SVR) was 70.2% in those with the CC genotype and 25% in those with the CT genotype. Early virological response (EVR) in patients with the CC genotype (84.2%) was higher than in those with the CT genotype (25.0%). For rs8099917, patients with the TT genotype showed significantly higher in SVR and EVR than those with the TG/GG genotype (69.6% vs 33.3% and 82.1% vs 44.4%, respectively). With regards to the genotype frequency of the SNPs, the homozygous genotypes for rs12979860 (CC) or rs8099917 (TT) in Korean patients showed a significantly higher frequency as compared with other ethnicities; Caucasians, African-American, Hispanic, and Japanese. Conclusions: These results demonstrate that the genotypes rs12979860 CC and rs8099917 TT were more frequently observed in Korean patients compared to other ethnicities, and suggest that the genetic characteristics of patients may be prognostic factor that predicts antiviral response to PEG-IFN therapy for chronic hepatitis C. (C) 2011 Elsevier B.V. All rights reserved
Dark endmember in spectral feature space under variable atmosphere
No full textOne of the most important assumptions in most multispectral image transformation methods is that the position of the dark endmember is placed at the origin of the n-D spectral feature space regardless of the target spectral signature. A series of field experiments under varying illumination resulted that ‘shadowlines’, which hypothetically pass through the dark endmember, never pass directly through the origin of the spectral feature space. A conceptual radiative transfer model was derived and demonstrated its susceptibility to the proportion of scattered light from the sky. The model showed that the location of the dark endmember, defined as the 'dark point virtual endmember (DPVE)’, is assumed to be sensitive to the state of atmosphere. Further analysis also revealed that the DPVE plays an important role in defining the data distribution in spectral feature space. This study suggested that accurate estimation of DPVE could enable to reduce some of the uncertainties associated with conventional dark point atmospheric correction methods
Recommended from our members
Preliminary Geologic Map of the North Half of the Union Pass Quadrangle, Mohave County, Arizona
No full textPreliminary Geologic Map of the North Half of the Union Pass Quadrangle, Mohave County, Arizona. Includes one map sheet with cross section at 1:24,000 map scale.On 1/17/2014, F.L. Hillemeyer's name was removed from the author list per his request. (The request was forwarded to AZGS by J.E. Faulds.)Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected]
Building and Defining Behavioral Economics
No full textContains fulltext :
95156.pdf (Publisher’s version ) (Closed access)George Loewenstein, a prominent behavioral economist, recalls thatIn 1994, when Thaler, Camerer, Rabin, Prelec and I spent the year at the Center for Advanced Study in the Behavioral Sciences, we had a meeting to make a kind of final decision about what to call what we were doing. Remarkably, at that time, the name behavioral economics was not yet well established. I actually advocated “psychological economics,” and Thaler was strong on behavioral economics. I'm kind of glad that he prevailed; I think it's a better, catchier, label, although it creates confusion due to association with Behaviorism. (G. Loewenstein, personal email to author, June 16, 2008
The IPHAS catalogue of H alpha emission-line sources in the northern Galactic plane
No full textWe present a catalogue of point-source H alpha emission-line objects selected from the INT/WFC Photometric Ha Survey (IPHAS) of the northern Galactic plane. The catalogue covers the magnitude range 13 <= r' <= 19.5 and includes Northern hemisphere sources in the Galactic latitude range -5 degrees < b < 5 degrees. It is derived from similar to 1500 deg(2) worth of imaging data, which represents 80 per cent of the final IPHAS survey area. The electronic version of the catalogue will be updated once the full survey data become available. In total, the present catalogue contains 4853 point sources that exhibit strong photometric evidence for Ha emission. We have so far analysed spectra for similar to 300 of these sources, confirming more than 95 per cent of them as genuine emission-line stars. A wide range of stellar populations are represented in the catalogue, including early-type emission-line stars, active late-type stars, interacting binaries, young stellar objects and compact nebulae.
The spatial distribution of catalogue objects shows overdensities near sites of recent or current star formation, as well as possible evidence for the warp of the Galactic plane. Photometrically, the incidence of Ha emission is bimodally distributed in (r' - i'). The blue peak is made up mostly of early-type emission-line stars, whereas the red peak may signal an increasing contribution from other objects, such as young/active low-mass stars. We have cross-matched our H alpha-excess catalogue against the emission-line star catalogue of Kohoutek & Wehmeyer, as well as against sources in SIMBAD. We find that fewer than 10 per cent of our sources can be matched to known objects of any type. Thus IPHAS is uncovering an order of magnitude more faint (r' > 13) emission-line objects than were previously known in the Milky Way
Testing protoplanetary disc dispersal with radio emission
No full textWe consider continuum free–free radio emission from the upper atmosphere of protoplanetary discs as a probe of the ionized luminosity impinging upon the disc. Making use of previously computed hydrodynamic models of disc photoevaporation within the framework of extreme-ultraviolet (EUV) and X-ray irradiation, we use radiative transfer post-processing techniques to predict the expected free–free emission from protoplanetary discs. In general, the free–free luminosity scales roughly linearly with ionizing luminosity in both EUV- and X-ray-driven scenarios, where the emission dominates over the dust tail of the disc and is partial optically thin at cm wavelengths. We perform a test observation of GM Aur at 14–18?GHz and detect an excess of radio emission above the dust tail to a very high level of confidence. The observed flux density and spectral index are consistent with free–free emission from the ionized disc in either the EUV- or the X-ray-driven scenario. Finally, we suggest a possible route to testing the EUV- and X-ray-driven dispersal model of protoplanetary discs, by combining observed free–free flux densities with measurements of mass-accretion rates. On the point of disc dispersal one would expect to find an M?2? scaling with free–free flux in the case of EUV-driven disc dispersal or an ?* scaling in the case of X-ray-driven disc dispersa
The Benefits of Being Economics Professor A (and not Z)
No full textAlphabetic name ordering on multi-authored academic papers, which is the convention in the economics discipline and various other disciplines, is to the advantage of people whose last name initials are placed early in the alphabet. As it turns out, Professor A, who has been a first author more often than Professor Z, will have published more articles and experienced afaster growth rate over the course of her career as a result of reputation and visibility. Moreover, authors know that name ordering matters and indeed take ordering seriously: Several characteristics of an author group composition determine the decision to deviate from the default alphabetic name order to a significant extent.performance measurement, incentives, economists, name ordering
- …
