The Wisconsin H-Alpha Mapper Northern Sky Survey

The Wisconsin H-Alpha Mapper (WHAM) has surveyed the distribution and kinematics of ionized gas in the Galaxy above declination -30 degrees. The WHAM Northern Sky Survey (WHAM-NSS) has an angular resolution of one degree and provides the first absolutely-calibrated, kinematically-resolved map of the H-Alpha emission from the Warm Ionized Medium (WIM) within ~ +/-100 km/s of the Local Standard of Rest. Leveraging WHAM's 12 km/s spectral resolution, we have modeled and removed atmospheric emission and zodiacal absorption features from each of the 37,565 spectra. The resulting H-Alpha profiles reveal ionized gas detected in nearly every direction on the sky with a sensitivity of 0.15 R (3 sigma). Complex distributions of ionized gas are revealed in the nearby spiral arms up to 1-2 kpc away from the Galactic plane. Toward the inner Galaxy, the WHAM-NSS provides information about the WIM out to the tangent point down to a few degrees from the plane. Ionized gas is also detected toward many intermediate velocity clouds at high latitudes. Several new H II regions are revealed around early B-stars and evolved stellar cores (sdB/O). This work presents the details of the instrument, the survey, and the data reduction techniques. The WHAM-NSS is also presented and analyzed for its gross properties. Finally, some general conclusions are presented about the nature of the WIM as revealed by the WHAM-NSS.Comment: 42 pages, 14 figures (Fig 6-9 & 14 are full color); accepted for publication in 2003, ApJ, 149; Original quality figures (as well as data for the survey) are available at http://www.astro.wisc.edu/wham

New Measurements of the Motion of the Zodiacal Dust

Using the Wisconsin H-Alpha Mapper (WHAM), we have measured at high spectral resolution and high signal-to-noise the profile of the scattered solar Mg I 5184 absorption line in the zodiacal light. The observations were carried out toward 49 directions that sampled the ecliptic equator from solar elongations of 48\dg (evening sky) to 334\dg (morning sky) plus observations near +47\dg and +90\dg ecliptic latitude. The spectra show a clear prograde kinematic signature that is inconsistent with dust confined to the ecliptic plane and in circular orbits influenced only by the sun's gravity. In particular, the broadened widths of the profiles, together with large amplitude variations in the centroid velocity with elongation angle, indicate that a significant population of dust is on eccentric orbits. In addition, the wide, flat-bottomed line profile toward the ecliptic pole indicates a broad distribution of orbital inclinations extending up to about 30\dg - 40\dg with respect to the ecliptic plane. The absence of pronounced asymmetries in the shape of the profiles limits the retrograde population to less than 10% of the prograde population and also places constraints on the scattering phase function of the particles. These results do not show the radial outflow or evening--morning velocity amplitude asymmetry reported in some earlier investigations. The reduction of the spectra included the discovery and removal of extremely faint, unidentified terrestrial emission lines that contaminate and distort the underlying Mg I profile. This atmospheric emission is too weak to have been seen in earlier, lower signal-to-noise observations, but it probably affected the line centroid measurements of previous investigations.Comment: 24 pages, 8 figures, 1 table, to appear in ApJ v612; figures appear low-res only on scree

A tri-dimensional approach for auditing brand loyalty

Over the past twenty years brand loyalty has been an important topic for both marketing practitioners and academics. While practitioners have produced proprietary brand loyalty audit models, there has been little academic research to make transparent the methodology that underpins these audits and to enable practitioners to understand, develop and conduct their own audits. In this paper, we propose a framework for a brand loyalty audit that uses a tri-dimensional approach to brand loyalty, which includes behavioural loyalty and the two components of attitudinal loyalty: emotional and cognitive loyalty. In allowing for different levels and intensity of brand loyalty, this tri-dimensional approach is important from a managerial perspective. It means that loyalty strategies that arise from a brand audit can be made more effective by targeting the market segments that demonstrate the most appropriate combination of brand loyalty components. We propose a matrix with three dimensions (emotional, cognitive and behavioural loyalty) and two levels (high and low loyalty) to facilitate a brand loyalty audit. To demonstrate this matrix, we use the example of financial services, in particular a rewards-based credit card

The DLV System for Knowledge Representation and Reasoning

This paper presents the DLV system, which is widely considered the state-of-the-art implementation of disjunctive logic programming, and addresses several aspects. As for problem solving, we provide a formal definition of its kernel language, function-free disjunctive logic programs (also known as disjunctive datalog), extended by weak constraints, which are a powerful tool to express optimization problems. We then illustrate the usage of DLV as a tool for knowledge representation and reasoning, describing a new declarative programming methodology which allows one to encode complex problems (up to $\Delta^P_3$-complete problems) in a declarative fashion. On the foundational side, we provide a detailed analysis of the computational complexity of the language of DLV, and by deriving new complexity results we chart a complete picture of the complexity of this language and important fragments thereof. Furthermore, we illustrate the general architecture of the DLV system which has been influenced by these results. As for applications, we overview application front-ends which have been developed on top of DLV to solve specific knowledge representation tasks, and we briefly describe the main international projects investigating the potential of the system for industrial exploitation. Finally, we report about thorough experimentation and benchmarking, which has been carried out to assess the efficiency of the system. The experimental results confirm the solidity of DLV and highlight its potential for emerging application areas like knowledge management and information integration.Comment: 56 pages, 9 figures, 6 table

The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (II): Measurement of Foreground Zodiacal Light

We present a measurement of the absolute surface brightness of the zodiacal light (3900-5100A) toward a fixed extragalactic target at high ecliptic latitude based on moderate resolution (~1.3A per pixel) spectrophotometry obtained with the du Pont 2.5m telescope at Las Campanas Observatory in Chile. This measurement and contemporaneous Hubble Space Telescope data from WFPC2 and FOS comprise a coordinated program to measure the mean flux of the diffuse extragalactic background light (EBL). The zodiacal light at optical wavelengths results from scattering by interplanetary dust, so that the zodiacal light flux toward any extragalactic target varies seasonally with the position of the Earth. This measurement of zodiacal light is therefore relevant to the specific observations (date and target field) under discussion. To obtain this result, we have developed a technique that uses the strength of the zodiacal Fraunhofer lines to identify the absolute flux of the zodiacal light in the multiple-component night sky spectrum. Statistical uncertainties in the result are 0.6% (1 sigma). However, the dominant source of uncertainty is systematic errors, which we estimate to be 1.1% (1 sigma). We discuss the contributions included in this estimate explicitly. The systematic errors in this result contribute 25% in quadrature to the final error in our coordinated EBL measurement, which is presented in the first paper of this series.Comment: Accepted for publication in ApJ, 22 pages using emulateapj.sty, version with higher resolution figures available at http://www.astro.lsa.umich.edu/~rab/publications.html or at http://nedwww.ipac.caltech.edu/level5/Sep01/Bernstein2/frames.htm

Genetic evidence that two independent S-loci control RNase-based self-incompatibility in diploid strawberry

The self-incompatibility mechanism that reduces inbreeding in many plants of the Rosaceae is attributed to a multi-allelic S locus which, in the Prunoideae and Maloideae subfamilies, comprises two complementary genes, a stylar-expressed S-RNase and a pollen-expressed SFB. To elucidate incompatibility in the subfamily Rosoideae, stylar-specific RNases and self-(in)compatibility status were analysed in various diploid strawberries, especially Fragaria nubicola and F. viridis, both self-incompatible, and F. vesca, self-compatible, and in various progenies derived from them. Unexpectedly, two unlinked RNase loci, S and T, were found, encoding peptides distinct from Prunoideae and Maloideae S-RNases; the presence of a single active allele at either is sufficient to confer self-incompatibility. By contrast, in diploid Maloideae and Prunoideae a single locus encodes S-RNases that share several conserved regions and two active alleles are required for self-incompatibility. Our evidence implicates the S locus in unilateral inter-specific incompatibility and shows that S and T RNases can, remarkably, confer not only allele-specific rejection of cognate pollen but also unspecific rejection of Sn Tn pollen, where n indicates a null allele, consistent with the the presence of the pollen component, SFB, activating the cognitive function of these RNases. Comparison of relevant linkage groups between Fragaria and Prunus suggests that Prunus S-RNases, unique in having two introns, may have resulted from gene conversion in an ancestor of Prunus. In addition, it is shown that there is a non-S locus that is essential for self-incompatibility in diploid Fragaria

InGaAs/InP hot electron transistors grown by chemical beam epitaxy

In this letter, we report on the dc performance of chemical beam epitaxy grown InGaAs/InP hot electron transistors (HETs). The highest observed differential β (dIC/dIB) is over 100. The HETs have Pd/Ge/Ti/Al shallow ohmic base contacts with diffusion lengths less than 300 Å. Furthermore, we also demonstrated ballistic transport of electrons in an InGaAs/InP HET by obtaining an energy distribution of electrons with ∼60 meV full width at half maximum. The measured conduction band discontinuity of InGaAs/InP is 250.3 meV, which is 39.8% of the band gap difference.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70748/2/APPLAB-61-2-189-1.pd

Identities of the kauffman monoid K4 and of the Jones Monoid J4

Kauffman monoids Kn and Jones monoids Jn, n=2,3,…, are two families of monoids relevant in knot theory. We prove a somewhat counterintuitive result that the Kauffman monoids K3 and K4 satisfy exactly the same identities. This leads to a polynomial time algorithm to check whether a given identity holds in K4. As a byproduct, we also find a polynomial time algorithm for checking identities in the Jones monoid J4. © Springer Nature Switzerland AG 2020.M. V. Volkov—Supported by Ural Mathematical Center under agreement No. 075-02-2020-1537/1 with the Ministry of Science and Higher Education of the Russian Federation

Selective advantage of epigenetically disrupted cancer cells via phenotypic inertia.

The evolution of established cancers is driven by selection of cells with enhanced fitness. Subclonal mutations in numerous epigenetic regulator genes are common across cancer types, yet their functional impact has been unclear. Here, we show that disruption of the epigenetic regulatory network increases the tolerance of cancer cells to unfavorable environments experienced within growing tumors by promoting the emergence of stress-resistant subpopulations. Disruption of epigenetic control does not promote selection of genetically defined subclones or favor a phenotypic switch in response to environmental changes. Instead, it prevents cells from mounting an efficient stress response via modulation of global transcriptional activity. This "transcriptional numbness" lowers the probability of cell death at early stages, increasing the chance of long-term adaptation at the population level. Our findings provide a mechanistic explanation for the widespread selection of subclonal epigenetic-related mutations in cancer and uncover phenotypic inertia as a cellular trait that drives subclone expansion