cssi/SciSciGPT-SciSciNet huggingface dataset:
Gravity from a Modified Commutator

We show that a suitably chosen position-momentum commutator can elegantly describe many features of gravity, including the IR/UV correspondence and dimensional reduction ("holography"). Using the most simplistic example based on dimensional analysis of black holes, we construct a commutator which qualitatively exhibits these novel properties of gravity. Dimensional reduction occurs because the quanta size grow quickly with momenta, and thus cannot be "packed together" as densely as naively expected. We conjecture that a more precise form of this commutator should be able to quantitatively reproduce all of these features.
The promotion of the ≪ banking habit ≫ and economic development

Publisher Summary This chapter focuses on the effect of the promotion of the banking habit on economic development. In some countries, the profitability of new banks and of new branches to existing banks has been sufficient to cause the expansion; in most, however, the growth has been induced or encouraged by central bank policies and often spearheaded by government-owned banks. The chapter discusses the possible grounds upon which the case for a prior or leading expansion of the banking system can be based and to display some of the problems connected with each of these grounds. The conclusions that can be reached from such an analysis are fundamentally two: (1) a case can be made for pushing the growth of the banking system ahead of the real growth of the economy, however, it is far from indisputable; and (2) for a policy of rapid bank office expansion to be beneficial, other concomitant changes must be made in the structure and conduct of the financial system.
Sonographic Recognition of Postoperative Meningocele

Un cas chez une femme de 59 ans, observe 3 mois apres laminectomie L2-L5 et dissectomie L3-L4 pour hernie discale. Traitement chirurgical
Electrical packaging impact on source components in optical interconnects

A simulation study of source module components for use within optical interconnect systems is described. SPICE models of laser diodes, CMOS drivers, and electrical packages are developed and exercised to evaluate overall source module performance. Performance metrics for power dissipation, signal latency, wavelength chirp, and signal fidelity are used. The effects of laser diode threshold current, bias condition, and driving current level are determined with respect to these metrics. The influence of driver type and electrical packaging technologies on source module performance is also evaluated. Transmission Line models of printed wiring board (PWB), tape automated bonding (TAB), and flip-chip bonding (C4) are used to study package related effects. It is found that under appropriate operating conditions, PWB can achieve acceptable noise, power, and latency performance for data rates up to 500 MHz while flip-chip bonding is required to exceed data rates of 800 MHz for the cases studied. >
Assembly synthesis with subassembly partitioning for optimal in-process dimensional adjustability

Achieving the dimensional integrity for a complex structural assembly is a demanding task due to the manufacturing variations of parts and the tolerance relationship between them. Although assigning tight tolerances to all parts would solve the problem, an economical solution is taking advantage of small motions that joints allow, such that critical dimensions are adjusted during assembly processes. This paper presents a systematic method that decomposes product geometry at an early stage of design, selects joint types, and generates subassembly partitioning to achieve the adjustment of the critical dimensions during assembly processes. A genetic algorithm generates candidate assemblies based on a joint library specific for an application domain. Each candidate assembly is evaluated by an internal optimization routine that computes the subassembly partitioning for optimal in-process adjustability, by finding a series of minimum cuts on weighted graphs. A case study on a three-dimensional automotive space frame with the accompanying joint library is presented.
Top Quark Mass

In the present article, based on a series of three lectures, we describe ways in which the large top quark mass influences a number of processes, and some ideas about how it might arise. After a brief introduction to the pattern of masses and couplings of quarks and leptons and an overview of the top quark’s properties, we discuss in Section 2 the role of the top quark in mixing processes, such as particle-antiparticle mixing in the neutral kaon and B meson systems, and in other flavor-changing charge-preserving processes. Section 3 is devoted to precision electroweak experiments and the impact upon their interpretation of the precise measurements of the top quark’s mass which have recently been achieved at Fermilab (Section 4). Some brief remarks about top quark production in electron-positron collisions occupy Section 5, while Section 6 contains various speculations about the source of the top quark’s mass. (See also Graham Ross’ lectures at this Institute [1].) Section 7 concludes.
Determinants of the Returns‐Earnings Correlation*

. The weak correlation between accounting earnings and security returns documented by numerous empirical studies is an issue of concern in current accounting research. Given that price is determined not solely by accounting earnings but also by other sources of information about future earnings, this paper focuses on the relation between earnings and other information to understand the returns-earnings association. The analysis indicates that current earnings exhibit high explanatory power for returns if they correlate with expected future earnings (or with other information that reflects expected future earnings). A high price-to-earnings (P/E) ratio coupled with a high return on equity (ROE) can ex ante indicate earnings growth, and the earnings of firms with these attributes are positively correlated with future earnings. The high-growth subset obtains an impressive returns-earnings R2 of 31 percent and an earnings coefficient of 6.17, demonstrating that it is possible to identify firms whose earnings are strongly correlated with returns using a parsimonious set of firm characteristics. Resume. La faible correlation entre les benefices comptables et le rendement des titres de placement sur laquelle se sont penches de nombreux auteurs d'etudes empiriques retient aujourd'hui l'attention des chercheurs en comptabilite. Le cours des titres etant determine non seulement par les benefices comptables mais aussi par d'autres sources d'information relative aux benefices futurs, l'auteur s'interesse ici a la relation entre les benefices et d'autres renseignements, dans le but d'expliquer le lien entre rendement et benefices. L'analyse revele que les benefices courants ont un pouvoir explicatif eleve a l'egard du rendement si ce dernier est en correlation avec les benefices futurs prevus (ou avec d'autres renseignements indicateurs des benefices futurs prevus). Un ratio cours/benefice eleve associe a un rendement des capitaux propres eleve peut indiquer, ex ante, une croissance des benefices, et les benefices des entreprises qui possedent ces caracteristiques sont en correlation positive avec les benefices futurs. Le sous-groupe des entreprises a forte croissance obtient un R2 etonnant de 31 pour cent, resultat d'une analyse de regression du rendement par rapport aux benefices, et un coefficient de benefices de 6,17, ce qui demontre qu'il est possible de determiner quelles sont les entreprises dont les benefices presentent une forte correlation avec le rendement, lorsqu'on utilise un ensemble parcimonieux de caracteristiques des entreprises.
Chiral N‐Phosphonylimine Chemistry: Asymmetric Synthesis of N‐Phosphonyl β‐Amino Weinreb Amides

Various chiral N-phosphonyl β-amino Weinreb amides were synthesized by treating chiral N-phosphonyl imines with the lithium enolate of N-methoxy-N-methylacetamide. The N,N-protection groups on chiral N-phosphonyl imines and the types of deprotonation bases for enolate generation were found to be crucial for the successful synthesis. Eleven Weinreb amides were obtained in excellent chemical yields (92 to 98 %) and good to excellent diastereoselectivities (up to dr = 99:1). The absolute structures were unambiguously determined by converting the products into authentic samples and by comparing their optical rotation values.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Linear orbit parameters for the exact equations of motion

This paper defines the beta function and other linear orbit parameters using the exact equations of motion. The /spl beta/, /spl alpha/ and /spl psi/ functions are redefined using the exact equations. Expressions are found for the transfer matrix and the emittance. The differential equations for /spl eta/=x//spl beta//sup 1/2 / is found. New relationships between /spl alpha/, /spl beta/, /spl psi/ and /spl nu/ are derived.
An intelligent listening framework for capturing encounter notes from a doctor-patient dialog

Capturing accurate and machine-interpretable primary data from clinical encounters is a challenging task, yet critical to the integrity of the practice of medicine. We explore the intriguing possibility that technology can help accurately capture structured data from the clinical encounter using a combination of automated speech recognition (ASR) systems and tools for extraction of clinical meaning from narrative medical text. Our goal is to produce a displayed evolving encounter note, visible and editable (using speech) during the encounter. This is very ambitious, and so far we have taken only the most preliminary steps. We report a simple proof-of-concept system and the design of the more comprehensive one we are building, discussing both the engineering design and challenges encountered. Without a formal evaluation, we were encouraged by our initial results. The proof-of-concept, despite a few false positives, correctly recognized the proper category of single-and multi-word phrases in uncorrected ASR output. The more comprehensive system captures and transcribes speech and stores alternative phrase interpretations in an XML-based format used by a text-engineering framework. It does not yet use the framework to perform the language processing present in the proof-of-concept. The work here encouraged us that the goal is reachable, so we conclude with proposed next steps. Some challenging steps include acquiring a corpus of doctor-patient conversations, exploring a workable microphone setup, performing user interface research, and developing a multi-speaker version of our tools.
FROM "WHITE CHRISTMAS" TO SGT. PEPPER: THE CONCEPTUAL REVOLUTION IN POPULAR MUSIC

Irving Berlin, Cole Porter, and other songwriters of the Golden Era, the second quarter of the twentieth century, wrote popular songs that treated common topics clearly and simply. During the mid-1960s, Bob Dylan, John Lennon, and Paul McCartney created a new kind of popular music that was personal and often obscure. This shift, which transformed popular music from an experimental into a conceptual art, produced a distinct change in the creative life cycles of songwriters. Golden Era songwriters improved with experience and were generally at their best during their 30s and 40s, whereas since the mid-1960s, popular songwriters have been most imaginative early in their careers and have consistently done their best work during their 20s. The conceptual revolution in popular music occurred at a time when iconoclastic young innovators were making similar transformations in other arts: Jean-Luc Godard and his fellow New Wave directors created a conceptual revolution in film in the early 1960s, just when Andy Wa...
HMQV: a high-performance secure diffie-hellman protocol

The MQV protocol of Law, Menezes, Qu, Solinas and Vanstone is possibly the most efficient of all known authenticated Diffie-Hellman protocols that use public-key authentication. In addition to great performance, the protocol has been designed to achieve a remarkable list of security properties. As a result MQV has been widely standardized, and has recently been chosen by the NSA as the key exchange mechanism underlying “the next generation cryptography to protect US government information”. One question that has not been settled so far is whether the protocol can be proven secure in a rigorous model of key-exchange security. In order to provide an answer to this question we analyze the MQV protocol in the Canetti-Krawczyk model of key exchange. Unfortunately, we show that MQV fails to a variety of attacks in this model that invalidate its basic security as well as many of its stated security goals. On the basis of these findings, we present HMQV, a carefully designed variant of MQV, that provides the same superb performance and functionality of the original protocol but for which all the MQV's security goals can be formally proved to hold in the random oracle model under the computational Diffie-Hellman assumption. We base the design and proof of HMQV on a new form of “challenge-response signatures”, derived from the Schnorr identification scheme, that have the property that both the challenger and signer can compute the same signature; the former by having chosen the challenge and the latter by knowing the private signature key.
Nature and/or nurture? Analyzing the determinants of transit ridership across US urbanized areas

Public subsidy of transit services has increased dramatically in recent years, with little effect on overall ridership. Quite obviously, a clear understanding of the factors influencing transit ridership is central to decisions on investments in and the pricing and deployment of transit services. Yet the literature about the causes of transit use is quite spotty; most previous aggregate analyses of transit ridership have examined just one or a few systems, have not included many of the external, control variables thought to influence transit use, and have not addressed the simultaneous relationship between transit service supply and consumption. This study addresses each of these shortcomings by (1) conducting a cross-sectional analysis of transit use in 265 US urbanized areas, (2) testing dozens of variables measuring regional geography, metropolitan economy, population characteristics, auto/highway system characteristics, and transit system characteristics, and (3) constructing two-stage simultaneous equation regression models to account for simultaneity between transit service supply and consumption. We find that most of the variation in transit ridership among urbanized areas – in both absolute and relative terms – can be explained by factors outside of the control of public transit systems: (1) regional geography (specifically, area of urbanization, population, population density, and regional location in the US), (2) metropolitan economy (specifically, personal/household income), (3) population characteristics (specifically, the percent college students, recent immigrants, and Democratic voters in the population), and (4) auto/highway system characteristics (specifically, the percent carless households and nontransit/non-SOV trips, including commuting via carpools, walking, biking, etc.). While these external factors clearly go a long way toward determining the overall level of transit use in an urbanized area, we find that transit policies do make a significant difference. The observed range in both fares and service frequency in our sample could account for at least a doubling (or halving) of transit use in a given urbanized area. Controlling for the fact that public transit use is strongly correlated with urbanized area size, about 26% of the observed variance in per capita transit patronage across US urbanized areas is explained in the models presented here by service frequency and fare levels. The observed influence of these two factors is consistent with both the literature and intuition: frequent service draws passengers, and high fares drive them away.
Selection Against Demographic Stochasticity in Age-Structured Populations

It has been shown that differences in fecundity variance can influence the probability of invasion of a genotype in a population; i.e., a genotype with lower variance in offspring number can be favored in finite populations even if it has a somewhat lower mean fitness than a competitor. In this article, Gillespie's results are extended to population genetic systems with explicit age structure, where the demographic variance (variance in growth rate) calculated in the work of Engen and colleagues is used as a generalization of "variance in offspring number" to predict the interaction between deterministic and random forces driving change in allele frequency. By calculating the variance from the life-history parameters, it is shown that selection against variance in the growth rate will favor a genotypes with lower stochasticity in age-specific survival and fertility rates. A diffusion approximation for selection and drift in a population with two genotypes with different life-history matrices (and therefore different mean growth rates and demographic variances) is derived and shown to be consistent with individual-based simulations. It is also argued that for finite populations, perturbation analyses of both the mean and the variance in growth rate may be necessary to determine the sensitivity of fitness to changes in the life-history parameters.
Hash function-based secret sharing scheme designs

Secret sharing schemes create an effective method to safeguard a secret by dividing it among several participants. By using hash functions and the herding hashes technique, we first set up a (t + 1, n) threshold scheme that is perfect and ideal and then extend it to schemes for any general access structure. The schemes can be further set up as proactive or verifiable if necessary. The setup and recovery of the secret are efficient because of the fast calculation of the hash function. The proposed scheme is flexible because of the use of existing hash functions. Copyright © 2012 John Wiley & Sons, Ltd.
Neural network based classification of highway scenes for vehicle guidance

Summary form only given. Current segmentation and classification algorithms are not sufficiently robust to provide reliable real-time sensor-based vehicle guidance for intelligent vehicle highway systems. An alternative technique based on neural networks was developed for scene classification as these algorithms can handle missing and fuzzy data. The backpropagation algorithm was successfully used in conjunction with new activation functions for classification of roads, lane markers, shadows, grass, and edge transitions in real-highway scenes. 131 subregions of size 3*3 with known classes such as roads, lane markers, shadows, grass, and low- and high-edge transitions were extracted from 15 training images. Two different neural network architectures based on image and edge data were defined. The neural network was then trained for learning the characteristics of desired classes. After convergence of the training phase was completed, the test images were correctly classified into the desired classes. The training time of 2.14 h was significantly lower than that of days to a week, as reported by other researchers for similar applications. >
The Rhythmic Beat of the Revolution in Iran

This essay investigates three methods for reading topical events, in this case events in Iran in 2009. Timing, as in music, is part of the trick of Iranian (as also other) politics, In Part I, breaking news is read in terms of historically and structurally informed social theory, with an eye to how civil society and public spheres are structured. There is an aesthetics to these spheres, not simply a calculus of interests or a space where rational debate can be abstracted from the civil society into a political public sphere. The (dis)harmonics of the Karbala Paradigm and the Islamic and pre-Islamic reference system of the 1979 revolution have been rescored in the aftermath of the June 2009 elections. Part II draws out the technical infrastructure, both low tech and hi tech, within which social and cultural action happens and civil society is restructured. It calls attention to the way in which the Green Wave was a confluence of civil society movements of women, labor, students, and journalists, among others. Iran is seen as a key test bed for struggles over the control of the Internet, as state control becomes more flexible, targeted, and pervasive. Part III plays with a futuring method—like the scenario methods used in industry and the simulation techniques used in the sciences—to plan for and evaluate alternative social logics that can play out in uncertain and underdetermined futures. The scenario method, to be used iteratively with several axes, helps clarify where there is need for better mapping of the networks of the players and their “small worlds” (“six or two degrees of difference”) cross-faction relationships.
CsPb3Bi3Te8 and CsPb4Bi3Te9: low-dimensional compounds and the homologous series CsPbmBi3Te5 + m

Two new thermoelectric materials of quaternary bismuth telluride CsPb3Bi3Te8 and CsPb4Bi3Te9 are reported, which are members of a homologous series featuring anionic slabs [PbmBi3Te5 + m]− (m = 1–4) of monotonically increasing thickness.
Protecting-group-free diastereoselective C-C coupling of 1,3-glycols and allyl acetate through site-selective primary alcohol dehydrogenation.

The ability to discriminate between like functional groups, so as to transform organic molecules in a “site-selective” or “chemoselective” manner,[1] precludes the requirement of protecting groups and, hence, carries the potential to dramatically enhance synthetic efficiency.[2] Though an exceptionally daunting challenge, systematic efforts toward catalytic methods for the site-selective transformation of polyfunctional molecules have begun to emerge. For example, Miller[3] and Taylor[4] report catalytic methods for the site-selective manipulation of diols and higher polyols. Site-selective metal catalyzed cross-couplings have been catalogued.[5] Further, in what is perhaps the most formidable theatre for site-selectivity, impressive advances in catalytic methods for C-H functionalization have been achieved, as illustrated in the seminal work of Barton,[6a] Murai and Kakiuchi,[6b] and in more recent studies by Davies,[6c] Sanford,[6d] Yu,[6e] Daugulis,[6f] Baran[6g] and others.
Kleinian groups and the complex of curves

We examine the internal geometry of a Kleinian surface group and its relations to the asymptotic geometry of its ends, using the combinatorial structure of the complex of curves on the surface. Our main results give necessary conditions for the Kleinian group to have ‘bounded geometry’ (lower bounds on injectivity radius) in terms of a sequence of coecients (subsurface projections) computed using the ending invariants of the group and the complex of curves. These results are directly analogous to those obtained in the case of puncturedtorus surface groups. In that setting the ending invariants are points in the closed unit disk and the coecients are closely related to classical continuedfraction coecients. The estimates obtained play an essential role in the solution of Thurston’s ending lamination conjecture in that case.
Ultrafast photoinduced above-bandgap transparency in GaAs due to the dynamic Franz-Keldysh effect

We report the dynamic Franz-Keldysh effect in bulk GaAs. Ultrafast changes in transmission spectra near the band edge, including the first observation of photoinduced transparency as large as 40% are observed.
HST and Spitzer Observations of the HD 207129 Debris Ring

A debris ring around the star HD 207129 (G0V; d = 16.0 pc) has been imaged in scattered visible light with the ACS coronagraph on the Hubble Space Telescope (HST) and in thermal emission using MIPS on the Spitzer Space Telescope at λ = 70 μm (resolved) and 160 μm (unresolved). Spitzer IRS (λ = 7-35 μm) and MIPS (λ = 55-90 μm) spectrographs measured disk emission at λ> 28 μm. In the HST image the disk appears as a ~30 AU wide ring with a mean radius of ~163 AU and is inclined by 60° from pole-on. At 70 μm, it appears partially resolved and is elongated in the same direction and with nearly the same size as seen with HST in scattered light. At 0.6 μm, the ring shows no significant brightness asymmetry, implying little or no forward scattering by its constituent dust. With a mean surface brightness of V = 23.7 mag arcsec^(–2), it is the faintest disk imaged to date in scattered light. We model the ring's infrared spectral energy distribution (SED) using a dust population fixed at the location where HST detects the scattered light. The observed SED is well fit by this model, with no requirement for additional unseen debris zones. The firm constraint on the dust radial distance breaks the usual grain size-distance degeneracy that exists in modeling of spatially unresolved disks, and allows us to infer a minimum grain size of ~2.8 μm and a dust size distribution power-law spectral index of –3.9. An albedo of ~5% is inferred from the integrated brightness of the ring in scattered light. The low-albedo and isotropic scattering properties are inconsistent with Mie theory for astronomical silicates with the inferred grain size and show the need for further modeling using more complex grain shapes or compositions. Brightness limits are also presented for six other main-sequence stars with strong Spitzer excess around which HST detects no circumstellar nebulosity (HD 10472, HD 21997, HD 38206, HD 82943, HD 113556, and HD 138965).
Combinatorially interpreting generalized Stirling numbers

The Stirling numbers of the second kind n k (counting the number of partitions of a set of size n into k non-empty classes) satisfy the relation ( x D ) n f ( x ) = ? k ? 0 n k x k D k f ( x ) where f is an arbitrary function and D is differentiation with respect to x . More generally, for every word w in alphabet { x , D } the identity w f ( x ) = x ( # ( x 's?in? w ) - # ( D 's?in? w ) ) ? k ? 0 S w ( k ) x k D k f ( x ) defines a sequence ( S w ( k ) ) k of Stirling numbers (of the second kind) of w . Explicit expressions for, and identities satisfied by, the S w ( k ) have been obtained by numerous authors, and combinatorial interpretations have been presented.Here we provide a new combinatorial interpretation that, unlike previous ones, retains the spirit of the familiar interpretation of n k as a count of partitions. Specifically, we associate to each w a quasi-threshold graph G w , and we show that S w ( k ) enumerates partitions of the vertex set of G w into classes that do not span an edge of G w . We use our interpretation to re-derive a known explicit expression for S w ( k ) , and in the case w = ( x s D s ) n to find a new summation formula linking S w ( k ) to ordinary Stirling numbers. We also explore a natural q -analog of our interpretation.In the case w = ( x r D ) n it is known that S w ( k ) counts increasing, n -vertex, k -component r -ary forests. Motivated by our combinatorial interpretation we exhibit bijections between increasing r -ary forests and certain classes of restricted partitions.
Herding and bank runs

Abstract Traditional models of bank runs do not allow for herding effects, because in these models withdrawal decisions are assumed to be made simultaneously. I extend the banking model to allow a depositor to choose his withdrawal time. When he withdraws depends on his consumption type (patient or impatient), his private, noisy signal about the quality of the bank's portfolio, and the withdrawal histories of the other depositors. Some of these runs are efficient in that the bank is liquidated before the portfolio worsens. Others are not efficient; these are cases in which the herd is misled.
Electrodynamics of spin currents in superconductors

In recent work we formulated a new set of electrodynamic equations for superconductors as an alternative to the conventional London equations, compatible with the prediction of the theory of hole superconductivity that superconductors expel negative charge from the interior towards the surface. Charge expulsion results in a macroscopically inhomogeneous charge distribution and an electric field in the interior, and because of this a spin current is expected to exist. Furthermore, we have recently shown that a dynamical explanation of the Meissner effect in superconductors leads to the prediction that a spontaneous spin current exists near the surface of superconductors (spin Meissner effect). In this paper we extend the electrodynamic equations proposed earlier for the charge density and charge current to describe also the space and time dependence of the spin density and spin current. This allows us to determine the magnitude of the expelled negative charge and interior electric field as well as of the spin current in terms of other measurable properties of superconductors. We also provide a `geometric' interpretation of the difference between type I and type II superconductors, discuss how superconductors manage to conserve angular momentum, discuss the relationship between our model and Slater's seminal work on superconductivity, and discuss the magnitude of the expected novel effects for elemental and other superconductors.
Consciousness and cognitive access

This article concerns the interplay between two issues that involve both philosophy and neuroscience: whether the content of phenomenal consciousness is ‘rich’ or ‘sparse’, whether phenomenal consciousness goes beyond cognitive access, and how it would be possible for there to be evidence one way or the other.
Judicial review: a practising judge's perspective

In this lecture Justice Breyer examines three classical criticisms of constitutional judicial review. Those criticisms say that a grant to unelected judges of the power to set aside legislation as contrary to a written constitution leads to judicial decision-making that is (a) undemocratic, (b) subjective, and impractical. Justice Breyer describes features of the constitutional decision-making that do not dictate results in individual cases, but none the less hold the judges' 'subjective' will in check. He also describes necessary judicial efforts to focus upon considerations of administrative practicality. The description seeks, not to refute the criticisms in their entirety, but to help evaluate the extent to which those criticisms militate against the adoption of a system of constitutional judicial review.
C*-algebras associated with interval maps

For each piecewise monotonic map r of [0,1], we associate a pair of C*-algebras F τ and Or and calculate their K-groups. The algebra F τ is an AI-algebra. We characterize when F τ and Or are simple. In those cases, F τ has a unique trace, and Or is purely infinite with a unique KMS state. In the case that τ is Markov, these algebras include the Cuntz-Krieger algebras O A , and the associated AF-algebras F A . Other examples for which the K-groups are computed include tent maps, quadratic maps, multimodal maps, interval exchange maps, and β-transformations. For the case of interval exchange maps and of β-transformations, the C*-algebra Or coincides with the algebras defined by Putnam and Katayama-Matsumoto-Watatani, respectively.
Low-Rank Matrix and Tensor Completion via Adaptive Sampling

We study low rank matrix and tensor completion and propose novel algorithms that employ adaptive sampling schemes to obtain strong performance guarantees. Our algorithms exploit adaptivity to identify entries that are highly informative for learning the column space of the matrix (tensor) and consequently, our results hold even when the row space is highly coherent, in contrast with previous analyses. In the absence of noise, we show that one can exactly recover a n x n matrix of rank r from merely Ω(nr3/2 log(r)) matrix entries. We also show that one can recover an order T tensor using Ω(nrT-1/2T2 log(r)) entries. For noisy recovery, our algorithm consistently estimates a low rank matrix corrupted with noise using Ω(nr3/2polylog(n)) entries. We complement our study with simulations that verify our theory and demonstrate the scalability of our algorithms.
Two-dimensional gauge theories revisited

Abstract Two dimensional quantum Yang-Mills theory is reexamined using a non-abelian version of the Duistermaat-Heckman integration formula to carry out the functional integral. This makes it possible to explain properties of the theory that are inaccessible to standard methods and to obtain general expressions for intersection pairings on moduli spaces of flat connections on a two dimensional surface. The latter expressions agree, for gauge group SU (2), with formulas obtained recently by several methods.
Computing Node Polynomials for Plane Curves

According to the G¨ ottsche conjecture (now a theorem), the degree N d; of the Severi variety of plane curves of degreed with nodes is given by a polynomial ind, providedd is large enough. These "node polynomials" N (d) were determined by Vainsencher and Kleiman-Piene for 6 and 8, respectively. Building on ideas of Fomin and Mikhalkin, we develop an explicit algorithm for computing all node polynomials, and use it to compute N (d) for 14. Furthermore, we improve the threshold of polynomiality and verify Gconjecture on the optimal threshold up to 14. We also determine the first 9 coefficients of N (d), for general , settling and extending a 1994 conjecture of Di Francesco and Itzykson. R´ esum´ e. Selon la Conjecture de G¨ ottsche (maintenant un Th´` eme), le degr´
The Financing of Innovative Firms

To what extent are new and/or innovative firms fundamentally different from established firms, and therefore require a different form of financing? The theoretical background for this proposition is presented, and the empirical evidence on its importance is reviewed. Owing to the intangible nature of their investment, asymmetric-information and moral-hazard, these firms are more likely to be financed by equity than debt and behave in some cases as though they are cash-constrained, especially if they are small. Recognizing the role for public policy in this area, many countries have implemented specific policies to bring the cost of financing innovation more in line with the level that would prevail in the absence of market failures.
Replacing the Irreplaceable: Fast Algorithms for Team Member Recommendation

In this paper, we study the problem of TEAM MEMBER REPLACEMENT -- given a team of people embedded in a social network working on the same task, find a good candidate to best replace a team member who becomes unavailable to perform the task for certain reason (e.g., conflicts of interests or resource capacity). Prior studies in teamwork have suggested that a good team member replacement should bring synergy to the team in terms of having both skill matching and structure matching. However, existing techniques either do not cover both aspects or consider the two aspects independently. In this work, we propose a novel problem formulation using the concept of graph kernels that takes into account the interaction of both skill and structure matching requirements. To tackle the computational challenges, we propose a family of fast algorithms by (a) designing effective pruning strategies, and (b) exploring the smoothness between the existing and the new team structures. We conduct extensive experimental evaluations and user studies on real world datasets to demonstrate the effectiveness and efficiency. Our algorithms (a) perform significantly better than the alternative choices in terms of both precision and recall and (b) scale sub-linearly.
Wind Tunnel Database Development using Modern Experiment Design and Multivariate Orthogonal Functions

A wind tunnel experiment for characterizing the aerodynamic and propulsion forces and moments acting on a research model airplane is described. The model airplane called the Free-flying Airplane for Sub-scale Experimental Research (FASER), is a modified off-the-shelf radio-controlled model airplane, with 7 ft wingspan, a tractor propeller driven by an electric motor, and aerobatic capability. FASER was tested in the NASA Langley 12-foot Low-Speed Wind Tunnel, using a combination of traditional sweeps and modern experiment design. Power level was included as an independent variable in the wind tunnel test, to allow characterization of power effects on aerodynamic forces and moments. A modeling technique that employs multivariate orthogonal functions was used to develop accurate analytic models for the aerodynamic and propulsion force and moment coefficient dependencies from the wind tunnel data. Efficient methods for generating orthogonal modeling functions, expanding the orthogonal modeling functions in terms of ordinary polynomial functions, and analytical orthogonal blocking were developed and discussed. The resulting models comprise a set of smooth, differentiable functions for the non-dimensional aerodynamic force and moment coefficients in terms of ordinary polynomials in the independent variables, suitable for nonlinear aircraft simulation.
GUNS VERSUS BUTTER: A DISAGGREGATED ANALYSIS

Irior studies of the guns-versus-butter trade-off have focused on total military expenditures and subcomponents of welfare spending (educa- tion, health, and housing). I extend the analysis to include the major subcomponents of the defense budget. The results are consistent with Clayton's; Domke, Eichenberg, and Kelleher's; and Russett's findings of a lack of defense-welfare trade-off in the 1947-80 era but reveal very specific trade-offs during the Reagan years.
Sequence Dependence of Transcription Factor-Mediated DNA Looping

DNA is subject to large deformations in a wide range of biological processes. Two key examples illustrate how such deformations influence the readout of the genetic information: the sequestering of eukaryotic genes by nucleosomes and DNA looping in transcriptional regulation in both prokaryotes and eukaryotes. These kinds of regulatory problems are now becoming amenable to systematic quantitative dissection with a powerful dialogue between theory and experiment. Here, we use a single-molecule experiment in conjunction with a statistical mechanical model to test quantitative predictions for the behavior of DNA looping at short length scales and to determine how DNA sequence affects looping at these lengths. We calculate and measure how such looping depends upon four key biological parameters: the strength of the transcription factor binding sites, the concentration of the transcription factor, and the length and sequence of the DNA loop. Our studies lead to the surprising insight that sequences that are thought to be especially favorable for nucleosome formation because of high flexibility lead to no systematically detectable effect of sequence on looping, and begin to provide a picture of the distinctions between the short length scale mechanics of nucleosome formation and looping.
Thoracic Aortic Aneurysm: Reading the Enemy???s Playbook

Imagine if a sports team were able to read the opposing team’s playbook; this would be a boon of major proportions. Aortic diseases represent a virulent opponent for cardiac specialists and for our patients. Over the last 10 years, at the Yale Center for Thoracic Aortic Disease, we have made a concerted effort to learn more about the natural history of aortic diseases based on a data set including information on 3000 patients and 9000 years of patient follow-up and 9000 serial imaging studies. This analysis has given us glimpses into the playbook of thoracic aortic diseases; these glimpses have corrolaries in terms of the appropriate role and timing of surgical intervention. Aortic dissection is one of the most catastrophic acute natural events that can befall the human being. The pain of this disorder is often described by those affected as the most severe pain imaginable. Because acute aortic dissection often masquerades as a heart attack, its true incidence is often underestimated. If a middle-aged or elderly person presents to the emergency room with acute onset of chest pain, clutches his chest, and promptly dies, he is likely to be signed out as a “myocardial infarction”. In actual fact, many such presentations represent undiagnosed aortic dissections. It takes autopsy series to document the true incidence of acute aortic dissection. Such series have indicated that aortic dissection is actually the most common lethal condition affecting the human aorta, more common than the better appreciated ruptured abdominal aortic aneurysm... (excerpt)
Kerfuffle: a web tool for multi-species gene colocalization analysis

Background The evolutionary pressures that underlie the large-scale functional organization of the genome are not well understood in eukaryotes. Recent evidence suggests that functionally similar genes may colocalize (cluster) in the eukaryotic genome, suggesting the role of chromatin-level gene regulation in shaping the physical distribution of coordinated genes. However, few of the bioinformatic tools currently available allow for a systematic study of gene colocalization across several, evolutionarily distant species. Furthermore, most tools require the user to input manually curated lists of gene position information, DNA sequence or gene homology relations between species. With the growing number of sequenced genomes, there is a need to provide new comparative genomics tools that can address the analysis of multi-species gene colocalization.
Piperazimycins : Cytotoxic hexadepsipeptides from a marine-derived bacterium of the genus Streptomyces

Three potent cancer cell cytotoxins, piperazimycins A-C (1-3), have been isolated from the fermentation broth of a Streptomyces sp., cultivated from marine sediments near the island of Guam. The structures of these cyclic hexadepsipeptides were assigned by a combination of spectral, chemical, and crystallographic methods. The piperazimycins are composed of rare amino acids, including hydroxyacetic acid, alpha-methylserine, gamma-hydroxypiperazic acid, and gamma-chloropiperazic acid. The novel amino acid residues 2-amino-8-methyl-4,6-nonadienoic acid and 2-amino-8-methyl-4,6-decadienoic acid were found as components of piperazimycins A and C, respectively. When screened in the National Cancer Institute's 60 cancer cell line panel, piperazimycin A exhibited potent in vitro cytotoxicity toward multiple tumor cell lines with a mean GI50 of 100 nM.
A comparison of two process tracing methods for choice tasks

The proliferation of computerized process tracing tools for monitoring information acquisition behavior demands an inquiry into their validity. This research compares information acquisition behavior for choice tasks using Mouselab, a computerized process tracing tool, and Eyegaze, an eye tracking system. In a paired difference experiment using apartment selection tasks and gambles, we found significant differences in information search patterns and subsequent choice behavior contingent upon the process tracing method. Overall, computerized process tracing tools increase the amount of effort needed to acquire information compared with eye tracking equipment. Our results show that subjects adopt information acquisition strategies to cope with the increased effort. These strategies tend to be more rigorous and systematic than those observed with eye tracking equipment. Thus, computerized process tracing tools fundamentally alter the information processing behavior they are believed to track unobtrusively by limiting the ability of the decision maker to adapt their information processing behavior dynamically to the demands of the data. Additional research is needed to explore the magnitude and consequences of these differences.
Compression of single-crystal magnesium oxide to 118 GPa and a ruby pressure gauge for helium pressure media

The pressure-volume equation of state (EoS) of single-crystal MgO has been studied in diamondanvil cells loaded with helium to 118 GPa and in a non-hydrostatic KCl pressure medium to 87 GPa using monochromatic synchrotron X-ray diffraction. A third-order Birch-Murnaghan fit to the nonhydrostatic P-V data (KCl medium) yields typical results for the initial volume, V0 = 74.698(7) A 3
Plasma Actuators for Separation Control of Low-Pressure Turbine Blades

This work involves the documentation and control of flow separation that occurs over turbine blades in the low-pressure-turbine (LPT) stage at the low Reynolds numbers typical of high-altitude cruise. We utilize a specially constructed linear cascade that is designed to study the flowfield over a generic LPT cascade consisting of Pratt and Whitney Pak B shaped blades. The center blade in the cascade is instrumented to measure the surface-pressure coefficient distribution. Optical access allows laser-Doppler-velocimetry measurements for boundary-layer profiles. Experimental conditions were chosen to give a range of chord Reynolds numbers from 10 4 to 10 5 , and a range of freestream turbulence levels from u'/U∞ = 0.08 to 2.85%. The surface-pressure measurements were used to define a region of separation and reattachment that depends on the freestream conditions
A Nonlinear Certainty Equivalent Approximation Method for Dynamic Stochastic Problems

This paper introduces a nonlinear certainty‐equivalent approximation method for dynamic stochastic problems. We first introduce a novel, stable, and efficient method for computing the decision rules in deterministic dynamic economic problems. We use the results as nonlinear and global certainty‐equivalent approximations for solutions to stochastic problems, and compare their accuracy to the common linear and local certainty‐equivalent methods. Our examples demonstrate that this method can be applied to solve high‐dimensional problems with up to 400 state variables with acceptable accuracy. This method can also be applied to solve problems with inequality constraints. These features make the nonlinear certainty‐equivalent approximation method suitable for solving complex economic problems, where other algorithms, such as log‐linearization, fail to produce a valid global approximation or are far less tractable. New Keynesian DSGE model competitive equilibrium parallel computing sparse grid approximation real business cycle model C61 C63 C68 E31 E52
International Financial Aggregation and Index Number Theory: A Chronological Half-century Empirical Overview

This paper comprises a survey of a half century of research on international monetary aggregate data. We argue that since monetary assets began yielding interest, the simple sum monetary aggregates have had no foundations in economic theory and have sequentially produced one source of misunderstanding after another. The bad data produced by simple sum aggregation have contaminated research in monetary economics, have resulted in needless “paradoxes,” and have produced decades of misunderstandings in international monetary economics research and policy. While better data, based correctly on index number theory and aggregation theory, now exist, the official central bank data most commonly used have not improved in most parts of the world. While aggregation theoretic monetary aggregates exist for internal use at the European Central Bank, the Bank of Japan, and many other central banks throughout the world, the only central banks that currently make aggregation theoretic monetary aggregates available to the public are the Bank of England and the St. Louis Federal Reserve Bank. No other area of economics has been so seriously damaged by data unrelated to valid index number and aggregation theory. In this paper we chronologically review the past research in this area and connect the data errors with the resulting policy and inference errors. Future research on monetary aggregation and policy can most advantageously focus on extensions to exchange rate risk and its implications for multilateral aggregation over monetary asset portfolios containing assets denominated in more than one currency. The relevant theory for multilateral aggregation with exchange rate risk has been derived by Barnett (J Econom 136(2):457–482, 2007) and Barnett and Wu (Ann Finance 1:35–50, 2005).