Theory of Rare B Decays

Theoretical aspects of rare $B$ decays are reviewed. The focus is on the relation between short-distance interactions and physical observables. It is argued that there remain significant uncertainties in the theoretical treatment of certain important quantities. (Talk presented at the International Symposium on Vector Boson Interactions, University of California, Los Angeles, February 1-3, 1995)Comment: 12 pages, uses REVTeX with aps.sty, epsf.sty, floats.sty; 10 uuencoded .eps figures include

White-Light Continuum in Stellar Flares

In this talk, we discuss the formation of the near-ultraviolet and optical continuum emission in M dwarf flares through the formation of a dense, heated chromospheric condensation. Results are used from a recent radiative-hydrodynamic model of the response of an M dwarf atmosphere to a high energy flux of nonthermal electrons. These models are used to infer the charge density and optical depth in continuum emitting flare layers from spectra covering the Balmer jump and optical wavelength regimes. Future modeling and observational directions are discussed.Comment: 9 pages, 2 figures. Invited review talk submitted to the proceedings of the IAU Symposium 320 "Solar and Stellar Flares and Their Effects on Planets" (eds. A. G. Kosovichev, S. L. Hawley, P. Heinzel) held on 10-14 August, 2015, in Honolulu, US

Who Put the \u3ci\u3eQuo\u3c/i\u3e in Quid Pro Quo?: Why Courts Should Apply \u3ci\u3eMcDonnell\u3c/i\u3e ’s “Official Act” Definition Narrowly

Federal prosecutors have several tools at their disposal to bring criminal charges against state and local officials for their engagement in corrupt activity. Section 666 federal funds bribery and § 1951 Hobbs Act extortion, two such statuary tools, have coexisted for the past thirty-six years, during which time § 666 has seen an increasing share of total prosecutions while the Hobbs Act’s share of prosecutions has fallen commensurately. In the summer of 2016, the U.S. Supreme Court decided McDonnell v. United States—a decision that threatens to quicken the demise of Hobbs Act extortion in favor of § 666. If McDonnell is interpreted to apply to Hobbs Act extortion but not to § 666, we can expect the latter to become the unchallenged favorite of federal prosecutors as well as increased litigation over whether § 666 bribery contains a quid pro quo requirement. This is likely to occur given § 666’s coverage of the same corrupt behavior, expansive jurisdictional hook, and, following McDonnell, lower difficulty of proving violations within some circuits. To avoid this eventuality, lower courts should distinguish McDonnell because of its unique procedural posture and continue to apply the existing quid pro quo framework. Before meaningful change to our federal bribery statutes can take place, the courts of appeals must first find consensus over whether and when § 666 requires the government to prove the existence of a quid pro quo

Classifying sentiment in microblogs: is brevity an advantage?

Microblogs as a new textual domain offer a unique proposition for sentiment analysis. Their short document length suggests any sentiment they contain is compact and explicit. However, this short length coupled with their noisy nature can pose difficulties for standard machine learning document representations. In this work we examine the hypothesis that it is easier to classify the sentiment in these short form documents than in longer form documents. Surprisingly, we find classifying sentiment in microblogs easier than in blogs and make a number of observations pertaining to the challenge of supervised learning for sentiment analysis in microblogs

An evaluation of the role of sentiment in second screen microblog search tasks

The recent prominence of the real-time web is proving both challenging and disruptive for information retrieval and web data mining research. User-generated content on the real-time web is perhaps best epitomised by content on microblogging platforms, such as Twitter. Given the substantial quantity of microblog posts that may be relevant to a user's query at a point in time, automated methods are required to sift through this information. Sentiment analysis offers a promising direction for modelling microblog content. We build and evaluate a sentiment-based filtering system using real-time user studies. We find a significant role played by sentiment in the search scenarios, observing detrimental effects in filtering out certain sentiment types. We make a series of observations regarding associations between document-level sentiment and user feedback, including associations with user profile attributes, and users' prior topic sentiment

Crowdsourced real-world sensing: sentiment analysis and the real-time web

The advent of the real-time web is proving both challeng- ing and at the same time disruptive for a number of areas of research, notably information retrieval and web data mining. As an area of research reaching maturity, sentiment analysis oers a promising direction for modelling the text content available in real-time streams. This paper reviews the real-time web as a new area of focus for sentiment analysis and discusses the motivations and challenges behind such a direction