cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis and Applications of Small Molecule Libraries.

One of the initial steps in the development of therapeutic agents is the identification of lead compounds that bind to the receptor or enzyme target of interest. Many analogs of these lead compounds are then synthesized to define the key recognition elements for maximal activity. In general, many compounds must be evaluated in both the lead identification and optimization steps. Increasing burdens have been placed on these efforts due to the large number of new therapeutic targets that continue to be identified thorough modern molecular biology methods.1 To address this demand, very powerful chemical and biological methods have been developed for the generation of large combinatorial libraries of peptides2 and oligonucleotides3 that are then screened against a receptor or enzyme to identify high-affinity ligands or potent inhibitors, respectively. While these studies have clearly demonstrated the power of library synthesis and screening strategies, peptides and oligonucleotides generally have poor oral activities and rapid in vivo clearance;4 therefore their utility as bioavailable therapeutic agents is often limited. Due to the favorable pharmacokinetic properties of many small organic molecules (<600-700 molecular weight),5 the design, synthesis, and evaluation of libraries of these compounds6 has rapidly become a major frontier in organic chemistry. Lorin A. Thompson was born in Lexington, KY, in 1970. He received the Bachelor of Science degree from the University of North Carolina, Chapel Hill, in 1992 where he worked under the guidance of Joseph Desimone. He is currently pursuing his doctorate in the laboratory of Jonathan Ellman at UC Berkeley where he is the 1994 Glaxo-Wellcome fellow. His research interests include the development of synthetic methodology for organic library construction.
Calibrated griz magnitudes of Tycho stars: All-sky photometric calibration using bright stars

Photometric calibration to ~5% level is frequently needed at arbitrary celestial location. However, existing all-sky astronomical catalogs do not reach this accuracy, and time consuming photometric calibration procedures are required. I fitted the Hipparcos B-T and V-T magnitudes, along with the 2MASS J, H, and K magnitudes of Tycho-2-catalog stars with stellar spectral templates. From the best-fit spectral template derived for each star, I calculated its synthetic SDSS griz magnitudes and constructed an all-sky catalog of griz magnitudes of bright stars (V ≾ 12). Testing this method on SDSS photometric-telescope observations, I find that the photometric accuracy, for a single star, is usually about 0.12, 0.12, 0.10, and 0.08 mag (1 σ), for the g, r, i, and z-bands, respectively. However, by using ~10 such stars, the typical errors per calibrated field (systematic + statistical) can be reduced to about 0.04, 0.03, 0.02, and 0.02 mag, in the g, r, i, and z-bands, respectively. Therefore, in cases for which several calibration stars can be observed in the field of view of an instrument, accurate photometric calibration is possible.
IS THE BOOK‐TO‐MARKET RATIO A MEASURE OF RISK?

We develop a leverage-based alternative to traditional asset pricing models to investigate whether the book-to-market ratio acts as a proxy for risk. We argue that the book-to-market ratio should act as a proxy because of the expected relations between (1) financial risk and measures of capital structure based on the market value of equity and (2) asset risk and measures of capital structure based on the book value of equity. We find no relation between average stock returns and the book-to-market ratio in all-equity firms after controlling for firm size, and an inverse relation between average stock returns and the book-to-market ratio in firms with a negative book value of equity.
Frequency-Independent Modal Damping for Flexural Structures via a Viscous "Geometric" Damping Model

*This paper considers the damped transverse vibration of flexural structures. Viscous damping models available to date suffer from the deficiency that predicted modal damping is strongly frequency-dependent, a situation not often encountered in experiments with builtup structures. Strain-based viscous damping, which corresponds to the case of stiffnessproportional damping, yields modal damping that increases linearly with frequency. Motion-based viscous damping, which corresponds to the case of mass-proportional damping, yields modal damping that decreases linearly with frequency. The proposed model introduces a viscous “geometric” damping term in which a resisting shear force is proportional to the time rate of change of the slope. In a discretized (finite element) context, the resulting damping matrix resembles the geometric stiffness matrix used to account for the effects of membrane loads on lateral stiffness. For an illustrative example of a simplysupported beam, this model yields constant modal damping that is independent of frequency. For some boundary conditions, the corresponding mode shapes are real. These conclusions are verified through additional finite element analysis. Such a viscous damping model should prove useful to researchers and engineers who need a time-domain damping model that exhibits realistic frequency-independent damping.
Reservoirs for Comets: Compositional Differences Based on Infrared Observations

Tracing measured compositions of comets to their origins continues to be of keen interest to cometary scientists and to dynamical modelers of Solar System formation and evolution. This requires building a taxonomy of comets from both present-day dynamical reservoirs: the Kuiper Belt (hereafter KB), sampled through observation of ecliptic comets (primarily Jupiter Family comets, or JFCs), and the Oort cloud (OC), represented observationally by the long-period comets and by Halley Family comets (HFCs). Because of their short orbital periods, JFCs are subjected to more frequent exposure to solar radiation compared with OC comets. The recent apparitions of the JFCs 9P/Tempel 1 and 73P/Schwassmann-Wachmann 3 permitted detailed observations of material issuing from below their surfaces—these comets added significantly to the compositional database on this dynamical class, which is under-represented in studies of cometary parent volatiles. This chapter reviews the latest techniques developed for analysis of high-resolution spectral observations from ∼2–5 μm, and compares measured abundances of native ices among comets. While no clear compositional delineation can be drawn along dynamical lines, interesting comparisons can be made. The sub-surface composition of comet 9P, as revealed by the Deep Impact ejecta, was similar to the majority of OC comets studied. Meanwhile, 73P was depleted in all native ices except HCN, similar to the disintegrated OC comet C/1999 S4 (LINEAR). These results suggest that 73P may have formed in the inner giant planets’ region while 9P formed farther out or, alternatively, that both JFCs formed farther from the Sun but with 73P forming later in time.
Symmetries and special states in two-dimensional string theory

Abstract We use the W∝ symmetry of c = 1 quantum gravity to compute matrix model special state correlation functions. The results are compared, and found to agree, with expectations from the Liouville model.
The Radiometric and Pointing Calibration of SECCHI COR1 on STEREO

c ∞ Springer •••• Abstract COR1 is the innermost coronagraph of the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) instrument suite aboard the twin Solar Terrestrial Relations Observatory (STEREO) spacecraft. The paired COR1 telescopes observe the white-light K-corona from 1.4 to 4 solar radii in a waveband 22.5 nm wide centered on the Hfi line at 656 nm. An internal polarizer allows the measurement of both total and polarized brightness. The co-alignment of the two COR1 telescopes is derived from the star ‚ Aquarii for the Ahead spacecraft, and from an occultation of the Sun by the Moon for Behind. Observa- tions of the planet Jupiter are used to establish absolute photometric calibrations for each telescope. The intercalibration of the two COR1 telescopes are compared using coronal mass ejection observations made early in the mission, when the spacecraft were close together. Comparisons are also made with the Solar and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph (LASCO) C2 and Mauna Loa Solar Observatory Mk4 coronagraphs.
On the Lego-Teichmüller game

For a smooth oriented surface Σ, denote byM(Σ) the set of all ways to represent Σ as a result of gluing together standard spheres with holes (“the Lego game”). In this paper we give a full set of simple moves and relations which turnM(Σ) into a connected and simply-connected 2-complex. Results of this kind were first obtained by Moore and Seiberg, but their paper contains serious gaps. Our proof is based on a different approach and is much more rigorous.
Tight lower bounds for Shellsort

Shellsort is a simple classic algorithm that runs competitively on both mid-sized and nearly sorted files. It uses an increment sequence, the choice of which can drastically affect the algorithm's running time. Due to the results of Pratt, the running time of Shellsort was long thought to be Θ(N3/2) for increment sequences that are "almost geometric". However, recent results have lowered the upper bound substantially, although the new bounds were not known to be tight.
Improved upper and lower time bounds for parallel random access machines without simultaneous writes

The time required by a variant of the PRAM (a parallel machine model which consists of sequential processors which communicate by reading and writing into a common shared memory) to compute a certain class of functions called critical functions (which include the Boolean OR of n bits) is studied. Simultaneous reads from individual cells of the shared memory are permitted, but simultaneous writes are not. It is shown that any PRAM which computes a critical function must take at least $0.5\log n - O(1)$ steps, and that there exists a critical function which can be computed in $0.57\log n - O(1)$ steps. These bounds represent an improvement in the constant factor over those previously known.
Adsorption of oxygen on the tungsten (110) plane at low temperatures; spectroscopic measurements

Abstract The adsorption of oxygen on the W(110) plane was carried out at 26 K and investigated by means of ultraviolet and X-ray photoelectron spectroscopy. It was found that atomic oxygen is adsorbed first to essentially saturation coverage (O/W = 0.6) before adsorption of molecular oxygen occurs. The spectrum of the latter is very similar to that of gas phase O2 but the shift to weaker binding energies is greater for the 1 s level than for the valence orbitals.
Rapid Establishment of Therapeutic Serum Concentrations of Salicylates

A minimum serum salicylate concentration of 150 microgram/ml is required to control certain inflammatory disease processes. A loading regimen designed to rapidly achieve this minimal level was evaluated in six normal volunteers (age 22 to 27 years, weight 70.5 to 84.1 kg) using a randomized crossover design. The control group received 650 mg aspirin (ASA) every 4 hours for 48 hours. The loading regimen was 2600 mg ASA divided into two equal doses 4 hours apart. Maintenance dosing of 650 mg ASA every 4 hours was then started 4 hours after the completion of the loading regimen and continued for 40 hours. Serum samples were drawn at 0, 2, 4, 6, 8, 12, 24, 36, and 48 hours after initiation of the study and were assayed for salicylate concentration by UV spectrophotometry. Loading with aspirin produced serum concentrations which were significantly higher (P less than 0.01) for the first 24 hours and reduced the time to reach 150 microgram/ml (15.3 +/- 5.9 hours versus 30.4 +/- 8.65 hours, P less than 0.001) for five of six subjects when compared to a conventional regimen. One subject did not achieve 150 microgram/ml at 48 hours with either regimen. Considerable intersubject variation in serum concentration was noted at 48 hours for both regimens. We suggest that a loading regimen for aspirin may have utility for patients in whom rapid attainment of a therapeutic antiinflammatory serum concentration is desirable.
Irregular Wakimoto modules and the Casimir connection

We study some non-highest weight modules over an affine Kac–Moody algebra \({\hat{\mathfrak g}}\) at the non-critical level. Roughly speaking, these modules are non-commutative localizations of some non-highest weight “vacuum” modules. Using free field realization, we embed some rings of differential operators in endomorphism rings of our modules. These rings of differential operators act on a localization of the space of coinvariants of any \({\hat{\mathfrak g}}\)-module with respect to a certain level subalgebra. In a particular case this action is identified with the Casimir connection.
Quadratic Residues and Non-Residues in Arithmetic Progression

The distribution problem for residues and non-residues has been intensively studied for 175 years using a rich variety of formulations and techniques. The work done in Chap. 7 gave a window through which we viewed one of these formulations and also saw a very important technique used to study it. Another problem that has been studied almost as long and just as intensely is concerned with the arithmetic structure of residues and non-residues. In this chapter, we will sample one aspect of that very important problem by studying when residues and non-residues form very long sequences in arithmetic progression. The first major advance in that problem came in 1939 when Harold Davenport proved the existence of residues and non-residues which form arbitrarily long sets of consecutive integers. As an introduction to the circle of ideas on which the work of this chapter is based, we briefly discuss Davenport’s results and the technique that he used to obtain them in Sect. 9.1. Davenport’s approach uses another application of the Dirichlet-Hilbert trick, which we used in the proofs of Theorems 4.12 and 5.13 presented in Chap. 5, together with an ingenious estimate of the absolute value of certain Legendre-symbol sums with polynomial values in their arguments. Davenport’s technique is quite flexible, and so we will adapt it in order to detect long sets of residues and non-residues in arithmetic progression. In Sect. 9.2, we will formulate our results precisely as a series of four problems which will eventually be solved in Sects. 9.4 and 9.10. This will require the estimation of the sums of values of Legendre symbols with polynomial arguments a la Davenport, which estimates we will derive in Sect. 9.3 by making use of a very important result of Andr Weil concerning the number of rational points on a nonsingular algebraic curve over ℤ∕p ℤ. In addition to these estimates, we will also need to calculate a term which will be shown to determine the asymptotic behavior of the number of sets of residues or non-residues which form long sequences of arithmetic progressions, and this calculation will be performed in Sects. 9.6–9.9. Here we will see how techniques from combinatorial number theory are applied to study residues and non-residues. In Sect. 9.11, an interesting class of examples will be presented, and we will use it to illustrate exactly how the results obtained in Sect. 9.10, together with some results of Sect. 9.11, combine to describe asymptotically how many sets there are of residues or non-residues which form long arithmetic progressions. Finally, the last section of this chapter discusses a result which, in certain interesting situations, calculates the asymptotic density of the set of primes which have residues and non-residues which form long sets of specified arithmetic progressions.
Predicting the Yields of Photometric Surveys for Transiting Extrasolar Planets

We develop a method for predicting the yield of transiting planets from a photometric survey given the parameters of thesurvey(nightsobserved,bandpass,exposuretime,telescopeaperture,locationsof thetargetfields,observational conditions, and detector characteristics), as well as the underlying planet properties (frequency, period and radius distributions). Using our updated understanding of transit surveys provided by the experiences of the survey teams, we account for those factors that have proven to have the greatest effect on the survey yields. Specifically, we include the effects of the surveys’ window functions, adopt revised estimates of the giant planet frequency, account for the number and distribution of main-sequence stars in the survey fields, and include the effects of Galactic structure and interstellar extinction. We approximate the detectability of a planetary transit using a signal-to-noise ratio (S/N) formulation. We argue that our choice of detection criterion is the most uncertain input to our predictions, and has the largesteffectontheresultingplanetyield.Thus,drawingrobustinferencesaboutthefrequencyof planetsfromtransit surveys will require that the survey teams impose and report objective, systematic, and quantifiable detection criteria. Nevertheless, with reasonable choices for the minimum S/N, we calculate yields that are generally lower, more accurate, and more realistic than previous predictions. As examples, we apply our method to the Trans-Atlantic Exoplanet Survey, the XO survey, and the Kepler mission. We discuss red noise and its possible effects on planetary detections. We conclude with estimates of the expected detection rates for future wide-angle synoptic surveys.
Devices for optical interconnects to chips

This tutorial will discuss the requirements for devices for optical interconnects to chips, and recent progress in devices that are integrable with silicon technology, including germanium quantum wells.
Trivalent Cation-Controlled Phase Space of New U(IV) Fluorides, Na3MU6F30 (M = Al3+, Ga3+, Ti3+, V3+, Cr3+, Fe3+): Mild Hydrothermal Synthesis Including an in Situ Reduction Step, Structures, Optical, and Magnetic Properties

A series of new, complex U(IV) fluorides, namely, Na3MU6F30 (M = Al3+, Ga3+, Ti3+, V3+, Cr3+, and Fe3+), containing trivalent transition- and main-group metal cations were synthesized via an in situ reduction step of U(VI) to U(IV). Single crystals of the series were grown in high yield under mild hydrothermal conditions and were characterized by single-crystal X-ray diffraction. The reported compounds crystallize in the trigonal space group P3c1 and exhibit complex crystal structures with a three-dimensional (3-D) framework composed of corner- and edge-shared UF9 polyhedra. The arrangement of U2F16 dimers forms two types of hexagonal channels, where MF6 polyhedra and sodium atoms are located. The most interesting structural feature is the presence of the 3-D framework that can accommodate various transition-metal ions in low oxidation states, indicating that the framework acts as an excellent host. Trivalent transition metal ions, even reduced Ti3+ and V3+, were stabilized by both the rigid framework an...
Occurrences of possible hydrated sulfates in the southern high latitudes of Mars

Abstract Hydrated sulfate minerals record the history of water and habitable environments on Mars, yet prior studies of them have neglected a vast region surrounding the planet’s south pole. Some of the few sulfates reported there are localized to putative ancient volcanoes that may have erupted under an ice sheet, possibly forming sulfates via hydrothermal alteration. Alternatively, sulfates may have formed more recently from sunlight causing minor melting of polar ices and the weathering of embedded dust particles, a process thought to explain the sulfates found near Mars’ north pole. To test these hypotheses, we searched for southern high-latitude sulfates using the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on the Mars Reconnaissance Orbiter (MRO), focusing on regions that include putative volcanoes or geologically similar landforms. In 217 targeted images, we used spectral parameters to identify regions of interest from which we extracted spectra. The spectra were then visually compared to laboratory spectra to identify possible hydrated mineral constituents. In this paper, we present spectra from 16 of the images and statistics derived from the full set of 217, along with spectra from one mapping tile. We find that hydrated sulfates are found throughout the southern high latitudes suggesting a ubiquitous process for hydrated mineral formation and/or the relocation of hydrated minerals due to a long history of impacts, aeolian transport, weathering and periglacial processes.
(3+1)-TQFTs and Topological Insulators

Levin-Wen models are microscopic spin models for topological phases of matter in (2+1)-dimension. We introduce a generalization of such models to (3 + 1)-dimension based on unitary braided fusion categories, also known as unitary premodular categories. We discuss the ground state degeneracy on 3-manifolds and statistics of excitations which include both points and defect loops. Potential connections with recently proposed fractional topological insulators and projective ribbon permutation statistics are described.
Information and preference aggregation

We investigate the implications of relaxing Arrow's independence of irrelevant alternatives axiom while retaining transitivity and the Pareto condition. Even a small relaxation opens a floodgate of possibilities for nondictatorial and efficient social choice.
Gateless AlGaN/GaN HEMT response to block co-polymers

Abstract Gateless AlGaN/GaN high electron mobility transistor (HEMT) structures exhibit large changes in source-drain current upon exposing the gate region to various block co-polymer solutions. The polar nature of some of these polymer chains lead to a change of surface charges in gate region on the HEMT, producing a change in surface potential at the semiconductor/liquid interface. The nitride sensors appear to be promising for a wide range of chemical gas, combustion gas, liquid and strain sensing.
Multiple Concentric Annuli for Characterizing Spatially Nonuniform Backgrounds

A method is presented for estimating the background at a given location on a sky map by interpolating the estimated background from a set of concentric annuli that surround this location. If the background is nonuniform but smoothly varying, this method provides a more accurate (although less precise) estimate than can be obtained with a single annulus. Several applications of multiannulus background estimation are discussed, including direct testing for point sources in the presence of a nonuniform background, the generation of surrogate maps for characterizing false alarm rates, and precise testing of the null hypothesis that the background is uniform.
Oxidation-Initiated Nazarov Cyclization of Vinyl Alkoxyallenes

A mild method for the diastereoselective formation of C4, C5-disubstituted cyclopentenones has been developed, involving formation of a pentadienyl cation via diastereoselective oxidation of a vinyl alkoxyallene. Conrotatory electrocyclization provides the cyclopentenone product. The broad scope, mild conditions, and uncommon substitution pattern accessible through this transformation make it a useful addition to the existing repertoire of cyclopentenone synthetic methods.
Learning Multisensory Representations for Auditory-Visual Transfer of Sequence Category Knowledge: A Probabilistic Language of Thought Approach

If a person is trained to recognize or categorize objects or events using one sensory modality, the person can often recognize or categorize those same (or similar) objects and events via a novel modality. This phenomenon is an instance of cross-modal transfer of knowledge. Here, we study the Multisensory Hypothesis which states that people extract the intrinsic, modality-independent properties of objects and events, and represent these properties in multisensory representations. These representations underlie cross-modal transfer of knowledge. We conducted an experiment evaluating whether people transfer sequence category knowledge across auditory and visual domains. Our experimental data clearly indicate that we do. We also developed a computational model accounting for our experimental results. Consistent with the probabilistic language of thought approach to cognitive modeling, our model formalizes multisensory representations as symbolic “computer programs” and uses Bayesian inference to learn these representations. Because the model demonstrates how the acquisition and use of amodal, multisensory representations can underlie cross-modal transfer of knowledge, and because the model accounts for subjects’ experimental performances, our work lends credence to the Multisensory Hypothesis. Overall, our work suggests that people automatically extract and represent objects’ and events’ intrinsic properties, and use these properties to process and understand the same (and similar) objects and events when they are perceived through novel sensory modalities.
Denotational cost semantics for functional languages with inductive types

A central method for analyzing the asymptotic complexity of a functional program is to extract and then solve a recurrence that expresses evaluation cost in terms of input size. The relevant notion of input size is often specific to a datatype, with measures including the length of a list, the maximum element in a list, and the height of a tree. In this work, we give a formal account of the extraction of cost and size recurrences from higher-order functional programs over inductive datatypes. Our approach allows a wide range of programmer-specified notions of size, and ensures that the extracted recurrences correctly predict evaluation cost. To extract a recurrence from a program, we first make costs explicit by applying a monadic translation from the source language to a complexity language, and then abstract datatype values as sizes. Size abstraction can be done semantically, working in models of the complexity language, or syntactically, by adding rules to a preorder judgement. We give several different models of the complexity language, which support different notions of size. Additionally, we prove by a logical relations argument that recurrences extracted by this process are upper bounds for evaluation cost; the proof is entirely syntactic and therefore applies to all of the models we consider.
Two-dimensional axisymmetric Child-Langmuir scaling law

The one-dimensional Child-Langmuir law has been extended to two dimensions by numerical simulation in planar geometries . The space charge limit in two dimensions is examined. Simulations were done with no applied magnetic field as well as with a large longitudinal magnetic field to restrict motion of particles to 1D. The ratio of the observed current density limit JCL2 to the theoretical one-dimensional value JCL1 is found to be a mono- tonically decreasing function of the ratio of emission radius (r) to gap separation (L). This result is in agreement with the planar results, where the emission area is proportional to the cathode width. The simulations were run in the particle in cell code. Least-squares fits to a log-log plot for no applied magnetic field.
The Generalized Composite Commodity Theorem and Food Demand Estimation

This article reports tests of aggregation over consumer food products and estimates of aggregate food demand elasticities. Evidence that food demand variables follow unit root processes leads us to build on and simplify existing tests of the Generalized Composite Commodity Theorem. We compute food demand elasticities using a method of cointegration that is shown to apply to a convenient but nonlinear functional form. Estimates are based on consumer reported expenditure data rather than commercial disappearance data. Appropriately specified models of consumer demand are central to market analysis. It has been established that a valid equilibrium for markets characterized by diverse firms or diverse consumer products depends on downward-sloping composite demand curves (Heiner, Braulke, Wohlgenant) or on valid indirect utility functions (Chavas and Cox). Given the large number of consumer food products, food demand and price analysis must be implemented at some level of product aggregation. Improper aggregation can lead to biased estimates of welfare loss associated with public policies, biased estimates of consumer and derived demand elasticities, and misleading tests of market power. Testing for consistent aggregation over food products and estimating aggregate consumer food demand elasticities are the subjects of this article. By far, the most common justification for aggregation has been separable preferences. One reason for its popularity has been the lack of a viable alternative. Tests of the Composite Commodity Theorem (Hicks, Leontief, Lewbel) are always rejected because it restricts relative prices within a group to remain fixed over time. On the other hand, aggregation based on weak separability is often rejected (Diewert and Wales, Eales and Unnevehr).
Cloud features and zonal wind measurements of Saturn's atmosphere as observed by Cassini/VIMS

[1] We present an analysis of data about Saturn's atmosphere from Cassini's Visual and Infrared Mapping Spectrometer (VIMS), focusing on the meteorology of the features seen in the 5 μm spectral window. We present VIMS mosaics and discuss the morphology and general characteristics of the features backlit by Saturn's thermal emission. We have also constructed a zonal wind profile from VIMS feature tracking observation sequences using an automated cloud feature tracker. Comparison with previously constructed profiles from Voyager and Cassini imaging data reveals broad similarities, suggesting minimal vertical shear of the zonal wind. However, areas of apparent wind shear are present in the VIMS zonal wind profile at jet stream cores. In particular, our analysis shows that the equatorial jet reaches speeds exceeding 450 m s−1, similar to speeds obtained during the Voyager era. This suggests that recent inferences of relatively slower jet speeds of ∼275–375 m s−1 are confined to the upper troposphere and that the deep (>1 bar) jet has not experienced a significant slowdown. Our measurements of the numerous dark, spotted features seen in the VIMS mosaics reveals that most of these features have diameters less than 1000 km and reside in confined zonal bands between jet stream cores. We propose that these spot features are vortices and that VIMS and Imaging Science Subsystem are sensing the same vortices at two different pressure levels. The local structure at the zonal jet streams remains complex, as VIMS may be sensing cloud features that are deeper than the NH3 cloud deck.
Near-optimal Anomaly Detection in Graphs using Lovasz Extended Scan Statistic

The detection of anomalous activity in graphs is a statistical problem that arises in many applications, such as network surveillance, disease outbreak detection, and activity monitoring in social networks. Beyond its wide applicability, graph structured anomaly detection serves as a case study in the difficulty of balancing computational complexity with statistical power. In this work, we develop from first principles the generalized likelihood ratio test for determining if there is a well connected region of activation over the vertices in the graph in Gaussian noise. Because this test is computationally infeasible, we provide a relaxation, called the Lovasz extended scan statistic (LESS) that uses submodularity to approximate the intractable generalized likelihood ratio. We demonstrate a connection between LESS and maximum a-posteriori inference in Markov random fields, which provides us with a poly-time algorithm for LESS. Using electrical network theory, we are able to control type 1 error for LESS and prove conditions under which LESS is risk consistent. Finally, we consider specific graph models, the torus, k-nearest neighbor graphs, and e-random graphs. We show that on these graphs our results provide near-optimal performance by matching our results to known lower bounds.
An adaptive analog noise-predictive decision-feedback equalizer

In this paper, an adaptive noise-predictive decision-feedback equalizer (NPDFE) is presented. The NPDFE architecture and its implementation are described. The NPDFE consists of an analog finite-impulse-response (FIR) forward equalizer, a recursive analog equalizer for noise prediction, and a decision-feedback equalizer (DFE). The recursive equalizer reduces noise enhancement and improves the signal-to-noise ratio (SNR) at the decision slicer input. The prototype targets a magnetic recording channel modeled by a Lorentzian impulse response. Measured results show that compared to a conventional DFE with FIR forward equalizer, the NPDFE achieves a SNR improvement of about 2 dB with PW/sub 50/=2.5T. The NPDFE consumes 130 mW at a data rate of 100 Mb/s and occupies 1.3 mm/sup 2/ of die area in a 0.5-/spl mu/m CMOS process.
A Cross-match of 2MASS and SDSS. II. Peculiar L Dwarfs, Unresolved Binaries, and the Space Density of T Dwarf Secondaries

We present the completion of a program to cross-correlate the Sloan Digital Sky Survey Data Release 1 (SDSS DR1) and Two-Micron All-Sky Survey (2MASS) Point Source Catalog in search for extremely red L and T dwarfs. The program was initiated by Metchev and collaborators, who presented the findings on all newly identified T dwarfs in SDSS DR1 and estimated the space density of isolated T0-T8 dwarfs in the solar neighborhood. In the current work, we present most of the L dwarf discoveries. Our red-sensitive (z – J ≥ 2.75 mag) cross-match proves to be efficient in detecting peculiarly red L dwarfs, adding two new ones, including one of the reddest known L dwarfs. Our search also nets a new peculiarly blue L7 dwarf and, surprisingly, two M8 dwarfs. We further broaden our analysis to detect unresolved binary L or T dwarfs through spectral template fitting to all L and T dwarfs presented here and in the earlier work by Metchev and collaborators. We identify nine probable binaries, six of which are new and eight harbor likely T dwarf secondaries. We combine this result with current knowledge of the mass ratio distribution and frequency of substellar companions to estimate an overall space density of 0.005-0.05 pc^(–3) for individual T0-T8 dwarfs.
Is the Internet an effective mechanism for reducing corruption experience? Evidence from a cross-section of countries

This article develops an indicator of Internet awareness on corruption as described in Goel et al. (2012) to see how this impacts both corruption perceptions and corruption experience. The results confirm the finding of Goel et al. (2012) that corruption perceptions are highly influenced by Internet awareness. However, the effect Internet awareness has on corruption experience is unclear. This article finds that Internet awareness decreases the frequency of corruption experience of households, while it increases the frequency of corruption experience in firms. Overall, the results suggest that the effect Internet awareness has on corruption is highly sensitive to the corruption measures used and the time the Internet data is constructed.
Time-inconsistency of VaR and time-consistent alternatives

We show that VaR (Value-at-Risk) is not time-consistent and discuss examples where this can lead to dynamically inconsistent behavior. Then we propose two time-consistent alternatives to VaR. The first one is a composition of one-period VaR's. It is time-consistent but not coherent. The second one is a composition of average VaR's. It is a time-consistent coherent risk measure.
Chiral Polyhedra in Ordinary Space, II

Chiral polyhedra in ordinary euclidean space E3 are nearly regular polyhedra; their geometric symmetry groups have two orbits on the flags, such that adjacent flags are in distinct orbits. This paper completely enumerates the discrete infinite chiral polyhedra in E3 with finite skew faces and finite skew vertex-figures. There are several families of such polyhedra of types {4,6}, {6,4} and {6,6}. Their geometry and combinatorics are discussed in detail. It is also proved that a chiral polyhedron in E3 cannot be finite. Part II of the paper will complete the classification of all chiral polyhedra in E3. All chiral polyhedra not described in Part I have infinite, helical faces and again occur in families. So, in effect, Part I enumerates all chiral polyhedra in E3 with finite faces.
Palladium-Catalyzed Completely Linear-Selective Negishi Cross-Coupling of Allylzinc Halides with Aryl and Vinyl Electrophiles

Completely linear: a general and practical palladium-catalyzed linear-selective Negishi coupling of 3,3-disubstituted allylzinc reagents with aryl, heteroaryl and vinyl electrophiles at ambient temperature is described. This method provides an effective means to access a wide range of prenylated arenes or skipped dienes in a completely linear-selective fashion, as demonstrated by a concise synthesis of the anti-HIV natural product siamenol. Finally, DFT calculations shed light on the origin of the excellent regioselectivity observed with the current catalyst system.
Molecular Diagnostic Testing for Inherited Thrombophilia Using Invader

Physicians in the United States and Europe began testing patients who had idiopathic thrombotic events for inherited risk factors in 1990s. The College of American Pathologists (CAP) offered proficiency testing for molecular genetic screening for thrombophilia in 1997. Today, a hypercoagulable workup including screening for inherited thrombophilia defects is becoming part of the standard of care in many parts of the world (1). Who, what, and when to test continue to be controversial and challenging questions (2); however, laboratories developing new or improved mutation detection methodologies have used the most commonly screened inherited thrombophilia polymorphism, factor V Leiden (R506Q), for many years (3). In the most recent CAP survey (MGL-A 2003), the most commonly employed method used in one-third of all participating clinical laboratories testing for factor V Leiden and prothrombin G20210A was the non-PCR-based method called Invader, developed by Third Wave Technologies. The remainder of the clinical laboratories reported testing for these variants using PCR-restriction fragment length polymorphism (RFLP), allele-specific PCR, and allele-specific hybridization. Emerging mutation detection technologies include DNA resequencing approaches such as pyrosequencing (4) fluorescence polarization detection (5), genotyping on microelectronic DNA chips like Nanogen's nanochip (6), and oligonucleotide hybridization with photocrosslinking (7). Invader technology is currently a medium-throughput, 96-well plate format assay that is sufficient for most hospital clinical laboratories. Although this assay format is not currently performed in a microarray format, Invader is amenable to performance on a solid support; specifically, the reaction can be performed on the surface of microspheres and the resulting fluorescence measured using flow cytometry (8). This chapter presents the method as well as some suggestions for utilizing the Invader system for mutation/polymorphism screening in general and for thrombophilia testing in particular.
A Model of Add-On Pricing

This paper examines competitive price discrimination with horizontal and vertical taste differences. Consumers with higher valuations for quality are assumed to have stronger brand preferences. Two models are considered: a standard competitive price discrimination model in which consumers observe all prices; and an "add-on pricing" game in which add-on prices are naturally unobserved and firms may advertise a base good at a low price in hopes of selling add-ons at high unadvertised prices. In the standard game price discrimination is self-reinforcing: the model sometimes has both equilibria in which the firms practice price discrimination and equilibria in which they do not. The analysis of the add-on pricing game focuses on the Chicago-school argument that profits earned on add-ons will be competed away via lower prices for advertised goods. A conclusion is that add-on practices can raise equilibrium profits by creating an adverse selection problem that makes price-cutting unappealing. Although profitable when jointly adopted, using add-on pricing is not individually rational in a simple extension with endogenous advertising practices and costless advertising. Several models that could account for add-on pricing are discussed.
Existence of Slow Steady Flows of Viscoelastic Fluids with Differential Constitutive Equations

Abstract : Questions of existence and uniqueness of steady flows of viscoelastic fluids have thus far not been understood, even for slow flows perturbing rest. This paper provides an existence result for slow flows with no in- and outflow boundaries. The fluid is assumed to be described by constitutive equations of a differential nature. The method used to prove existence is constructive and in fact very close to procedures used in numerical calculations.
The Gaussian free field in interlacing particle systems

We show that if an interlacing particle system in a two-dimensional lattice is a determinantal point process, and the correlation kernel can be expressed as a double integral with certain technical assumptions, then the moments of the fluctuations of the height function converge to that of the Gaussian free field. In particular, this shows that a previously studied random surface growth model with a reflecting wall has Gaussian free field fluctuations.
Polynomial constraints in causal Bayesian networks

We use the implicitization procedure to generate polynomial equality constraints on the set of distributions induced by local interventions on variables governed by a causal Bayesian network with hidden variables. We show how we may reduce the complexity of the implicitization problem and make the problem tractable in certain causal Bayesian networks. We also show some preliminary results on the algebraic structure of polynomial constraints. The results have applications in distinguishing between causal models and in testing causal models with combined observational and experimental data.
The Mass Distribution of Subgiant Planet Hosts

High mass stars are hostile to Doppler measurements due to rotation and activity on the main-sequence, so RV searches for planets around massive stars have relied on evolved stars. A large number of planets have been found around evolved stars with M > 1.5 M ☉. To test the robustness of mass determinations, Lloyd compared mass distributions of planet hosting subgiants with distributions from integrating isochrones and concluded that it is unlikely the subgiant planet hosts are this massive, but rather that the mass inferences are systematically in error. The conclusions of Lloyd have been called in to question by Johnson et al., who show TRILEGAL-based mass distributions that disagree with the mass distributions in Lloyd, which they attribute to Malmquist bias. Johnson et al. argue that the very small spectroscopic observational uncertainties favor high masses, and there are a large number of high mass sub giants in RV surveys. However, in this Letter, it is shown that Malmquist bias does not impact the mass distributions, but the mass distribution is sensitive to Galaxy model. The relationship needed to reconcile the subgiant planet host masses with any model of the Galactic stellar population is implausible, and the conclusion of Lloyd that spectroscopic mass determinations of subgiants are likely to have been overestimated is robust.
TESTING DISK-LOCKING IN NGC 2264

We test analytic predictions from different models of magnetospheric accretion, which invoke disk-locking, using stellar and accretion parameters derived from models of low-resolution optical spectra of 36 T Tauri stars (TTSs) in NGC 2264 (age {approx}3 Myr). Little evidence is found for models that assume purely dipolar field geometries; however, strong support is found in the data for a modified version of the X-wind model which allows for non-dipolar field geometries. The trapped flux concept in the X-wind model is key to making the analytic predictions which appear supported in the data. By extension, our analysis provides support for the outflows predicted by the X-wind as these also originate in the trapped flux region. In addition, we find no support in the data for accretion-powered stellar winds from young stars. By comparing the analysis presented here of NGC 2264 with a similar analysis of stars in Taurus (age {approx}1-2 Myr), we find evidence that the equilibrium interaction between the magnetic field and accretion disk in TTS systems evolves as the stars grow older, perhaps as the result of evolution of the stellar magnetic field geometry. We compare the accretion rates we derive with accretion rates based on U-band excess, findingmore » good agreement. In addition, we use our accretion parameters to determine the relationship between accretion and H{beta} luminosity, again finding good agreement with previously published results; however, we also find that care must be taken when applying this relationship due to strong chromospheric emission in young stars, which can lead to erroneous results in some cases.« less
Cotton Mather (1918–1999)

Cotton Mather, a name-sake and direct descendant of colonial New England's Cotton Mather, was a dominant figure in American geography during the second half of the twentieth century. When the expan...
Interactive analytical processing in big data systems: a cross-industry study of MapReduce workloads

Within the past few years, organizations in diverse industries have adopted MapReduce-based systems for large-scale data processing. Along with these new users, important new workloads have emerged which feature many small, short, and increasingly interactive jobs in addition to the large, long-running batch jobs for which MapReduce was originally designed. As interactive, large-scale query processing is a strength of the RDBMS community, it is important that lessons from that field be carried over and applied where possible in this new domain. However, these new workloads have not yet been described in the literature. We fill this gap with an empirical analysis of MapReduce traces from six separate business-critical deployments inside Facebook and at Cloudera customers in e-commerce, telecommunications, media, and retail. Our key contribution is a characterization of new MapReduce workloads which are driven in part by interactive analysis, and which make heavy use of query-like programming frameworks on top of MapReduce. These workloads display diverse behaviors which invalidate prior assumptions about MapReduce such as uniform data access, regular diurnal patterns, and prevalence of large jobs. A secondary contribution is a first step towards creating a TPC-like data processing benchmark for MapReduce.
A new flip-chip bonding technique using micromachined conductive polymer bumps

Using micromachining techniques with thick photoresists, a new conductive polymer flip-chip bonding technique that achieves both a low processing temperature and a high bumping alignment resolution has been developed in this work. By the use of UV-based photolithography with thick photoresists, molds for the flip-chip bumps have been patterned, filled with conductive polymers, and then removed, leaving molded conductive polymer bumps. After flip-chip bonding with the bumps, the contact resistances measured for 25 /spl mu/m-high bumps with 300 /spl mu/m/spl times/300 /spl mu/m area and 400 /spl mu/m/spl times/400 /spl mu/m area were 35 m/spl Omega/ and 12 m/spl Omega/ respectively. The conductive polymer flip-chip bonding technique developed in this work shows a very low contact resistance, simple processing steps, a high bumping alignment resolution (</spl plusmn/5 /spl mu/m), and a lower bonding temperature (/spl sim/170/spl deg/C). This new bonding technique has high potential to replace conventional flip-chip bonding technique for sensor and actuator systems, bio/chemical /spl mu/-TAS, optical MEMS, OE-MCM's, and electronic system applications.
Doubly resonant sum-frequency vibrational spectroscopy on a chiral monolayer

Infrared-visible doubly resonant sum-frequency spectroscopy has been successfully used to obtain optically active vibrational spectra of a chiral molecular monolayer. This establishes the technique as a unique tool for in situ probing of vibrational chirality.