cssi/SciSciGPT-SciSciNet huggingface dataset:
Nonparametric estimation of means on Hilbert manifolds and extrinsic analysis of mean shapes of contours

Motivated by the problem of nonparametric inference in high level digital image analysis, we introduce a general extrinsic approach for data analysis on Hilbert manifolds with a focus on means of probability distributions on such sample spaces. To perform inference on these means, we appeal to the concept of neighborhood hypotheses from functional data analysis and derive a one-sample test. We then consider the analysis of shapes of contours lying in the plane. By embedding the corresponding sample space of such shapes, which is a Hilbert manifold, into a space of Hilbert-Schmidt operators, we can define extrinsic mean shapes of random planar contours and their sample analogues. We then apply the general methods to this problem while considering the computational restrictions faced when utilizing digital imaging data. Comparisons of computational cost are provided to another method for analyzing shapes of contours.
Cause Marketing: Spillover Effects of Cause-Related Products in a Product Portfolio

The number of firms carrying a cause-related product has significantly increased in recent years. We consider a duopoly model of competition between firms in two products to determine which products a firm will link to a cause. We first test the behavioral underpinnings of our model in two laboratory experiments to demonstrate the existence of both a direct utility benefit to consumers from cause marketing (CM) and a spillover benefit onto other products in the portfolio. Linking one product in a product portfolio to a cause can therefore increase sales both of that product and, via a spillover effect, of other products in the firm's portfolio. We construct a CM game in which each firm chooses which products, if any, to place on CM. In the absence of a spillover benefit, a firm places a product on CM if and only if it can increase its price by enough to compensate for the cost of CM. Thus, in equilibrium, firms either have both products or neither product on CM. However, with the introduction of a spillover benefit to the second product, this result changes. We show that if a single firm in the market links only one product to a cause, it can raise prices on both products and earn a higher profit. We assume each firm has an advantage in one product and show that there is an equilibrium in which each firm links only its disadvantaged product to a cause. If the spillover effect is strong, there is a second equilibrium in which each firm links only its advantaged product to a cause. In each case, firms raise their prices on both products and earn higher profits than when neither firm engages in CM. We also show that a firm will never place its entire portfolio on CM. Overall, our work implies that, by carrying cause-related products, companies can not only improve their image in the public eye but also increase profits.
Childhood adversity and inflammatory processes in youth: A prospective study

Acute stress; Stressful life events; Prospective cohort; Avon Longitudinal Study of Parents and Children (ALSPAC) Summary Background: Retrospective studies show that childhood adversity is associated with systemic inflammation in adulthood. Few prospective studies have examined whether childhood adversity influences inflammation in an observable manner during childhood or adolescence and if these effects are sustained over time. Methods: Using longitudinal data from the Avon Longitudinal Study of Parents and Children, we examined associations between acute adverse events at seven time points prior to age 8 and inflammation at ages 10 and 15. Inflammatory markers at age 10 included interleukin-6 (IL-6; N = 4655) and C-reactive protein (CRP; N = 4647), and CRP was measured again at age 15 (N = 3286). We further evaluated whether body mass index (BMI), depression, or cigarette smoking mediated associations between adverse events and inflammation. Results: Adverse events in middle childhood (occurring between ages 6 to 8), as well as cumulative adversity from birth to 8 years, were associated with higher levels of IL-6 and CRP at age 10. Adverse events reported in early childhood (1.5 years) or middle childhood, and cumulative adversity from birth through 8 years predicted increased levels of CRP at age 15, and these associations persisted after adjustment for CRP at age 10. Some, but not all, of these associations were mediated by BMI.
Electron‐Donating and Rigid P‐Stereogenic Bisphospholane Ligands for Highly Enantioselective Rhodium‐Catalyzed Asymmetric Hydrogenations

The new P-stereogenic bisphospholane ligand (ZPHOS) shows high effectivity in the rhodium-catalyzed hydrogenation of various functionalized olefins.
Codes with monotonic codeword lengths

Abstract Minimum average codeword length coding under the constraint that the codewords are monotonically nondecreasing in length is studied. Bounds on the average length of an optimal “monotonie” code are derived, and sufficient conditions are given such that algorithms for optimal alphabetic codes can be used to find the optimal “monotonic” code.
Low frequency observations of emission nebulae and their electron temperatures

Radio observations of emission nebulae at 74 MHz are reported. Flux densities for NGC 1499, IC 405, IC 410, NGC 2024, NGC 2175, NGC 2237-46, and NGC 6820 are given. Most of the observed nebulae are found to be optically thick at 74 MHz. Combining the low frequency results with previously measured flux densities at high frequencies, it is shown that it is possible to derive the mean electron temperatures of the observed nebulae. The results show that the range in temperature is from 3200 to 6800 K.
Concrete Representation of Martingales

Let $(f_n)$ be a mean zero vector valued martingale sequence. Then there exist vector valued functions $(d_n)$ from $[0,1]^n$ such that $\int_0^1 d_n(x_1,\dots,x_n)\,dx_n = 0$ for almost all $x_1,\dots,x_{n-1}$, and such that the law of $(f_n)$ is the same as the law of $(\sum_{k=1}^n d_k(x_1,\dots,x_k))$. Similar results for tangent sequences and sequences satisfying condition (C.I.) are presented. We also present a weaker version of a result of McConnell that provides a Skorohod like representation for vector valued martingales.
Perfluoroalkenyl ethers of bile alcohols

Abstract Two synthetic routes are presented for the synthesis of bis- and tris-perfluoroalkenyloxy-substituted bile alcohols with an unsubstituted hydroxyl group in the hydrocarbon side chain. The first route involves selective protection of the 24-hydroxyl group of 3α, 7α, 12α, 24-cholan-tetrol followed by the attachment of 3α, 7α, 12α-hydroxyl groups to the perfluoroalkenyloxy linkages and removal of the protecting group. The second pathway is based on the synthesis of the tris-perfluoroalkenyloxy derivative of 3α, 7α, 12α-trihydroxy-chol-22-ene (or bis-perfluoroalkenyloxy derivative of 3α, 12α-dihydroxy-7-deoxy-chol-22-ene), followed by the hydrobaration of the double bond.
Spectroscopy and dynamics of excess electrons in clusters

Anionic clusters comprising solvent molecules and excess electrons can provide new insights into electron solvation in liquids, an intrinsically bulk phenomenon. This paper reviews experimental and theoretical studies of this class of clusters, focusing primarily on water cluster anions, , but also on iodide-water clusters, I−(H2O) n , and methanol cluster anions . Issues of particular interest include the relationship of time-resolved dynamics in these clusters to those of bulk solvated electrons, and the nature of the electron binding motifs supported by these clusters.
Implementing set-theoretic relational-query functions using highly parallel index-processing hardware

Hardware organizations for processing set-theoretic database query functions are presented. These organizations implement the functions by processing index trees. One advantage of this approach is that the index trees can be merged in a highly parallel fashion. Hardware organizations proposed here use the database machine approach, thus processing the index-trees on the fly. Experimental results giving the performances of these organizations are presented. Finally, a slight variation of the index tree representation, requiring much less storage for the index, is given.
Mapping the Local Halo: Statistical Parallax Analysis of SDSS Low-Mass Subdwarfs

We present a statistical parallax study of nearly 2000 M subdwarfs with photometry and spectroscopy from the Sloan Digital Sky Survey (SDSS). Statistical parallax analysis yields the mean absolute magnitudes, mean velocities, and velocity ellipsoids for homogenous samples of stars. We selected homogeneous groups of subdwarfs based on their photometric colors and spectral appearance. We examined the color-magnitude relations of low-mass subdwarfs and quantified their dependence on the newly refined metallicity parameter, ζ. We also developed a photometric metallicity parameter, δ(g – r), based on the g – r and r – z colors of low-mass stars and used it to select stars with similar metallicities. The kinematics of low-mass subdwarfs as a function of color and metallicity were also examined and compared to main-sequence M dwarfs. We find that the SDSS subdwarfs share similar kinematics to the inner halo and thick disk. The color-magnitude relations derived in this analysis will be a powerful tool for identifying and characterizing low-mass metal-poor subdwarfs in future surveys such as Gaia and LSST, making them important and plentiful tracers of the stellar halo.
Bootstrapping GMM estimators for time series

Abstract This paper considers the bootstrap for the GMM estimator of overidentified linear models when autocorrelation structures of moment functions are unknown. When moment functions are uncorrelated after finite lags, Hall and Horowitz, [1996. Bootstrap critical values for tests based on generalized method of moments estimators. Econometrica 64, 891–916] showed that errors in the rejection probabilities of the bootstrap tests are o ( T - 1 ) . However, this rate cannot be obtained with the HAC covariance matrix estimator since it converges at a nonparametric rate. By incorporating the HAC covariance matrix estimator in the Edgeworth expansion of the distribution, we show that the bootstrap provides asymptotic refinements when the characteristic exponent of the kernel function is greater than two.
A Simple Model for r-Process Scatter and Halo Evolution

Recent halo-star observations of heavy elements produced by rapid neutron capture (r-process) show a striking behavior: within a single star, the relative abundances of r-process elements heavier than Ba are the same as those of solar system matter, while across stars with similar metallicity Fe/H, the r/Fe ratio varies by more than 2 orders of magnitude. In this paper we present a simple analytic model that describes a star's abundances in terms of its "ancestry," i.e., the number of nucleosynthesis events (e.g., supernova explosions) that contributed to the star's composition. This model leads to a very simple analytic expression for the abundance scatter versus Fe/H, which is in good agreement with the data and with more sophisticated numerical models. We investigate two classes of scenarios for r-process nucleosynthesis, one in which r-process synthesis events occur in only ~4% of supernovae but iron synthesis is ubiquitous, and one in which iron nucleosynthesis occurs in only about 9% of supernovae (the Wasserburg-Qian model). We find that the predictions in these scenarios are similar for [Fe/H] -2.5, but that these models can be readily distinguished observationally by measuring the dispersion in r/Fe at [Fe/H] -3.
A Model of producer incentives for livestock disease management

We examine the management of livestock diseases from the producers‘ perspective, incorporating information and incentive asymmetries between producers and regulators. Using a stochastic dynamic model, we examine responses to different policy options including indemnity payments, subsidies to report at-risk animals, monitoring, and regulatory approaches to decreasing infection risks when perverse incentives and multiple policies interact. This conceptual analysis illustrates the importance of designing efficient combinations of regulatory and incentive-based policies.
Lifetime Analysis of Fusion Reactor First Wall Components

Linear elastic fracture mechanics is used to predict the growth of a semi-elliptical surface flaw through a thin-walled actively cooled 316 stainless steel first wall in a tokamak power reactor, which is subjected to pulsed surface heat fluxes, 14 MeV neutron irradiation and sputtering from particle bombardment. The results from an inelastic stress analysis, which includes thermal creep, irradiation creep, swelling, and wall thinning, are coupled to the crack growth calculations. The effects of temperature, R-ratio, threshold ..delta..K, neutron-induced embrittlement, creep crack growth and two-dimensional flaw shape changes are included. Predictions for a cylindrical blanket module with hemispherical first wall end cap indicate that severe reductions in lifetime can occur when radiation damage effects are included and demonstrate the need for high fluence data on da/dN and K /SUB 1c/ .
REMARKS ON NORMAL BASES

We prove that any Galois extension of a commutative ring with a normal basis and abelian Galois group of odd order has a self-dual normal basis. We apply this result to get a very simple proof of nonexistence of normal bases for certain extensions which are of interest in number theory.
Matrix Cartan Superdomains, Super Toeplitz-Operators, and Quantization

We present a general theory of non-perturbative quantization of a class of hermitian symmetric supermanifolds. The quantization scheme is based on the notion of a super Toeplitz operator on a suitable Z2-graded Hilbert spaces of super-holomorphic functions. The quantized supermanifold arises as the C*-algebra generated by all such operators. We prove that our quantization framework reproduces the invariant super Poisson structure on the classical supermanifold as Planck′s constant tends to zero.
Experiences With Using Solar Photovoltaics to Heat Domestic Water

The solar photovoltaic (PV) industry continues to make progress in increasing the efficiency while reducing the manufacturing costs of PV cells. Economies of scale are being realized as manufacturers expand their production capabilities. Products are commercially available that integrate photovoltaic cells within building facade, fenestration, and roofing components. Legislation and incentive programs by government and commercial entities are supporting both reduced first costs and greater rates of return. The combination of factors support improved cost-effectiveness. As this trend continues, more options for using PV become possible. One such application is a stand-alone, PV-direct, solar water heating application. Solar water heating can be effectively accomplished by directly using the DC power production from solar photovoltaic modules. A simple controller having multiple power relays connects the PV modules with different combinations of in-tank resistive elements. The controller actively changes the resistive combination so that the photovoltaic modules generate power at or near their maximum output. The technology, which has been patented, is applicable to configurations that use a single water heater and to two water heaters that are piped in series. Prototypes using both tank configurations were monitored at four field sites. This paper emphasizes the single-tank application and the field results from installations in Maryland and Florida.
Westerly Wind Bursts: ENSO’s Tail Rather than the Dog?.

Westerly wind bursts (WWBs) in the equatorial Pacific occur during the development of most El Nino events and are believed to be a major factor in ENSO’s dynamics. Because of their short time scale, WWBs are normally considered part of a stochastic forcing of ENSO, completely external to the interannual ENSO variability. Recent observational studies, however, suggest that the occurrence and characteristics of WWBs may depend to some extent on the state of ENSO components, implying that WWBs, which force ENSO, are modulated by ENSO itself. Satellite and in situ observations are used here to show that WWBs are significantly more likely to occur when the warm pool is extended eastward. Based on these observations, WWBs are added to an intermediate complexity coupled ocean–atmosphere ENSO model. The representation of WWBs is idealized such that their occurrence is modulated by the warm pool extent. The resulting model run is compared with a run in which the WWBs are stochastically applied. The modulation of WWBs by ENSO results in an enhancement of the slow frequency component of the WWBs. This causes the amplitude of ENSO events forced by modulated WWBs to be twice as large as the amplitude of ENSO events forced by stochastic WWBs with the same amplitude and average frequency. Based on this result, it is suggested that the modulation of WWBs by the equatorial Pacific SST is a critical element of ENSO’s dynamics, and that WWBs should not be regarded as purely stochastic forcing. In the paradigm proposed here, WWBs are still an important aspect of ENSO’s dynamics, but they are treated as being partially stochastic and partially affected by the large-scale ENSO dynamics, rather than being completely external to ENSO. It is further shown that WWB modulation by the large-scale equatorial SST field is roughly equivalent to an increase in the ocean–atmosphere coupling strength, making the coupled equatorial Pacific effectively self-sustained.
Introduction to the renormalization group

The basic idea of the renormalization group is introduced and illustrative examples are presented. Emphasis is put on the application to the theory of critical phenomena. This article is prepared for pedagogical purposes. It is written at a level that a second-year graduate student in physical sciences can understand. No previous knowledge of critical phenomena or field theory is needed. We make no attempt to survey the field or cover a wide range of subjects. On the contrary, we limit the scope to the most basic aspects. We choose to elaborate at length to make the basic idea clear and the definitions precise, and to go through the examples very carefully. We feel that once these basic aspect are understood, there will be no difficulty in confronting the rapidly expanding literature on this subject.
Perfectly secure message transmission

This paper studies the problem of perfectly secure communication in general network in which processors and communication lines may be faulty. Lower bounds are obtained on the connectivity required for successful secure communication. Efficient algorithms are obtained that operate with this connectivity and rely on no complexity-theoretic assumptions. These are the first algorithms for secure communication in a general network to simultaneously achieve the three goals of perfect secrecy, perfect resiliency, and worst-case time linear in the diameter of the network.
The Ketene‐Surrogate Coupling: Catalytic Conversion of Aryl Iodides into Aryl Ketenes through Ynol Ethers

tert-Butoxyacetylene is shown to undergo Sonogashira coupling with aryl iodides to yield aryl-substituted tert-butyl ynol ethers. These intermediates participate in a [1,5]-hydride shift, which results in the extrusion of isobutylene and the generation of aryl ketenes. The ketenes are trapped in situ with multiple nucleophiles or undergo electrocyclic ring closure to yield hydroxynaphthalenes and quinolines.
Deriving Grassland Management Factors for a Carbon Accounting Method Developed by the Intergovernmental Panel on Climate Change

Grassland management affects soil organic carbon (SOC) storage and can be used to mitigate greenhouse gas emissions. However, for a country to assess emission reductions due to grassland management, there must be an inventory method for estimating the change in SOC storage. The Intergovernmental Panel on Climate Change (IPCC) has developed a simple carbon accounting approach for this purpose, and here we derive new grassland management factors that represent the effect of changing management on carbon storage for this method. Our literature search identified 49 studies dealing with effects of management practices that either degraded or improved conditions relative to nominally managed grasslands. On average, degradation reduced SOC storage to 95% ± 0.06 and 97% ± 0.05 of carbon stored under nominal conditions in temperate and tropical regions, respectively. In contrast, improving grasslands with a single management activity enhanced SOC storage by 14% ± 0.06 and 17% ± 0.05 in temperate and tropical regions, respectively, and with an additional improvement(s), storage increased by another 11% ± 0.04. We applied the newly derived factor coefficients to analyze C sequestration potential for managed grasslands in the U.S., and found that over a 20-year period changing management could sequester from 5 to 142 Tg C yr−1 or 0.1 to 0.9 Mg C ha−1 yr−1, depending on the level of change. This analysis provides revised factor coefficients for the IPCC method that can be used to estimate impacts of management; it also provides a methodological framework for countries to derive factor coefficients specific to conditions in their region.
On the zero-error capacity threshold for deletion channels

We consider the zero-error capacity of deletion channels. Specifically, we consider the setting where we choose a codebook C consisting of strings of n bits, and our model of the channel corresponds to an adversary who may delete up to pn of these bits for a constant p. Our goal is to decode correctly without error regardless of the actions of the adversary. We consider what values of p allow non-zero capacity in this setting. We suggest multiple approaches, one of which makes use of the natural connection between this problem and the problem of finding the expected length of the longest common subsequence of two random sequences.
On asymptotics for the Airy process

The Airy process t→A(t), introduced by Prahofer and Spohn, is the limiting stationary process for a polynuclear growth model. Adler and van Moerbeke found a PDE in the variables s1,s2, and t for the probability Pr(A(0)≤s1, A(t)≤s2). Using this they were able, assuming the truth of a certain conjecture and appropriate uniformity, to obtain the first few terms of an asymptotic expansion for this probability as t→∞, with fixed s1 and s2. We shall show that the expansion can be obtained by using the Fredholm determinant representation for the probability. The main ingredients are formulas obtained by the author and C. A. Tracy in the derivation of the Painleve II representation for the distribution function F2 plus a few others obtained in the same way.
Cembranolide total synthesis. Anisomelic acid

Abstract The stereoselective total synthesis of (±)-anisomelic acid ( 34 ) has been achieved starting from aldehyde 7 , the ozonolysis product of geranyl acetate. Two key steps ensured the stereoselectivity of the synthesis. The first entailed a highly anti-selective addition of the allyltitanium derived from carbamate 15 to aldehyde 5 affording the enol carbamate allylic alcohol 16 . The second was a highly ( Z )-selective Horner-Emmons cyclization of the derived phosphono ester aldehyde 25 leading to the conjugated ester 27 . Further conversion led to the crystalline lactone 30 whose structure was confirmed through single crystal X-ray analysis. Equilibration of the conjugated double bond of 30 gave rise to a 1:1 mixture of the ( Z ) and ( E ) isomers. This result was foretold by molecular mechanics calculations.
An Analysis of Resolution Trust Corporation Transactions: Auction Market Process and Pricing

This article describes the operations of the Resolution Trust Corporation (RTC), examines the procedures it employs to resolve distressed Savings and Loan scenarios and investigates the pricing of transactions undertaken by the RTC. The RTC has been criticized for allegedly transferring properties to acquirers at “bargain” prices. The transactions involving publicly traded acquirers in RTC sales are examined from an auction theory perspective. Overall, there is little evidence that winning bidders experience stock price gains. There are, however, subsets of bidders for which the outcomes are predominantly negative. The only category of transactions which provide statistically significant gains to acquirers are Insured Deposit Transfers.
On the distribution of career longevity and the evolution of home-run prowess in professional baseball

Statistical analysis is a major aspect of baseball, from player averages to historical benchmarks and records. Much of baseball fanfare is based around players exceeding the norm, some in a single game and others over a long career. Career statistics serve as a metric for classifying players and establishing their historical legacy. However, the concept of records and benchmarks assumes that the level of competition in baseball is stationary in time. Here we show that power law probability density functions, a hallmark of many complex systems that are driven by competition, govern career longevity in baseball. We also find similar power laws in the density functions of all major performance metrics for pitchers and batters. The use of performance-enhancing drugs has a dark history, emerging as a problem for both amateur and professional sports. We find statistical evidence consistent with performance-enhancing drugs in the analysis of home runs hit by players in the last 25 years. This is corroborated by the findings of the Mitchell Report (2007), a two-year investigation into the use of illegal steroids in Major League Baseball, which recently revealed that over 5 percent of Major League Baseball players tested positive for performance-enhancing drugs in an anonymous 2003 survey.
Steroids in Pediatric Eosinophilic Esophagitis

Swallowed fluticasone and oral viscous budesonide are effective first-line therapies for eosinophilic esophagitis in children. Side effects are minimal without evidence of Cushing syndrome, as seen in treatment with systemic corticosteroids. New studies on alternative delivery systems and different corticosteroids (eg, ciclesonide) are encouraging. As knowledge of corticosteroids in eosinophilic esophagitis expands, newer questions continue to arise concerning dose, delivery, and choice of corticosteroids; long-term adverse effects; and maintenance therapies.
Natural inflation: consistency with cosmic microwave background observations of Planck and BICEP2

Natural inflation is a good fit to all cosmic microwave background (CMB) data and may be the correct description of an early inflationary expansion of the Universe. The large angular scale CMB polarization experiment BICEP2 has announced a major discovery, which can be explained as the gravitational wave signature of inflation, at a level that matches predictions by natural inflation models. The natural inflation (NI) potential is theoretically exceptionally well motivated in that it is naturally flat due to shift symmetries, and in the simplest version takes the form V()?=??4?[1???cos(N/f)]. A tensor-to-scalar ratio r?>?0.1 as seen by BICEP2 requires the height of any inflationary potential to be comparable to the scale of grand unification and the width to be comparable to the Planck scale. The Cosine Natural Inflation model agrees with all cosmic microwave background measurements as long as f???mPl (where mPl?=?1.22???1019?GeV) and ??~?mGUT?~?1016?GeV. This paper also discusses other variants of the natural inflation scenario: we show that axion monodromy with potential V?2/3 is inconsistent with the BICEP2 limits at the 95% confidence level, and low-scale inflation is strongly ruled out. Linear potentials V?? are inconsistent with the BICEP2 limit at the 95% confidence level, but are marginally consistent with a joint Planck/BICEP2 limit at 95%. We discuss the pseudo-Nambu Goldstone model proposed by Kinney and Mahanthappa as a concrete realization of low-scale inflation. While the low-scale limit of the model is inconsistent with the data, the large-field limit of the model is marginally consistent with BICEP2. All of the models considered predict negligible running of the scalar spectral index, and would be ruled out by a detection of running.
Unitarity of black hole evaporation in final-state projection models

Almheiri et al. have emphasized that otherwise reasonable beliefs about black hole evaporation are incompatible with the monogamy of quantum entanglement, a general property of quantum mechanics. We investigate the final-state projection model of black hole evaporation proposed by Horowitz and Maldacena, pointing out that this model admits cloning of quantum states and polygamous entanglement, allowing unitarity of the evaporation process to be reconciled with smoothness of the black hole event horizon. Though the model seems to require carefully tuned dynamics to ensure exact unitarity of the black hole S-matrix, for a generic final-state boundary condition the deviations from unitarity are exponentially small in the black hole entropy; furthermore observers inside black holes need not detect any deviations from standard quantum mechanics. Though measurements performed inside old black holes could potentially produce causality-violating phenomena, the computational complexity of decoding the Hawking radiation may render the causality violation unobservable. Final-state projection models illustrate how inviolable principles of standard quantum mechanics might be circumvented in a theory of quantum gravity.
Medically Uninsured Children in the United States: A Challenge to Public Policy

ABSTRACT: This article is an examination of the nature and extent of the problem presented by medically uninsured children in the United States. First, the characteristics of the uninsured population are explored with a description of how age, family income, and employment status disproportionately affect families with children. Second, the Medicaid program and its historically inadequate response to this growing problem of uninsured children is examined. Third, the relationship between insurance status and the health and development of children is discussed. Finally, recent public policy initiatives that have been enacted or proposed to address this inequity in the present health care system are reviewed with a recommendation to establish a “Universal Maternal and Child Health Program.” (J Sch Health. 1990;60(10):493–500)
Boolean Functions, Projection Operators, and Quantum Error Correcting Codes

This paper describes a fundamental correspondence between Boolean functions and projection operators in Hilbert space. The correspondence is widely applicable, and it is used in this paper to provide a common mathematical framework for the design of both additive and nonadditive quantum error correcting codes. The new framework leads to the construction of a variety of codes including an infinite class of codes that extend the original ((5, 6, 2)) code found by Rains It also extends to operator quantum error correcting codes.
Personal Investing: Advice, Theory, and Evidence

Data from a unique survey containing information on the composition of the respondents' total asset holdings—both inside and outside their retirement accounts—shed light on individual asset-allocation behavior. Individual asset allocations are consistent with the recommendations of expert practitioners and with the prescriptions of economic theory. The survey respondents maintain in cash and near-cash investments a proportion of their wealth that declines as wealth increases. They hold these safe assets outside their retirement accounts. The proportion of total assets that they hold in equities declines with age and rises with wealth. They do not appear to manage their assets across retirement and nonretirement accounts to maximize tax efficiency.
Methodological Frontiers of Public Finance Field Experiments

The purpose of this article is to demonstrate how a rich array of methods can be applied to increase the relevance of field experiments in public economics. Two cross-cutting themes are important in multiple phases of the research. First, greater statistical sophistication can draw more value from a field experiment without obscuring the simple and compelling information from the differences in average outcomes of intervention and control groups. Second, the methodological frontier is interdisciplinary, drawing on knowledge and techniques developed in psychology, anthropology, and sociology that can be adapted in order to make public finance field experiments more useful.
Decoupler Pylon: A Simple, Effective Wing/Store Flutter Suppressor

As an alternative to alleviating wing/store flutter by conventional passive methods or by more advanced active control methods, a quasi-passive concept, referred to as the decoupler pylon, is investigated which combines desirable features of both methods. Passive soft-spring/damper elements are used to decouple wing modes from store pitch modes, and a low-power control system maintains store alignment under changing mean loads. It is shown by analysis and wind tunnel tests that the decoupler pylon provides substantial increase in flutter speed and makes flutter virtually insensitive to inertia and center-of-gravity location of the store.
Lamp driver concepts for dielectric barrier discharge lamps and evaluation of a 110 W ballast

With temperature-independent light output and long usable lifetimes, Hg-free dielectric barrier discharge lamps (DBDLs) exhibit distinct advantages. Their electrical parameters - driving voltages up to some kV, predominant capacitive impedance and a power factor in the range of 0.3 differ considerably from those of well-known fluorescent lamps. Electronic ballasts for DBDLs have to cope with these properties while on the other hand a compromise between system performance and costs must be found. This paper gives an overview on existing concepts with their specific advantages and drawbacks. Furthermore, 110 W electronic ballast for the OSRAM PLANON Lamp is evaluated.
Assessment of the Integration of a HIS/RIS with a PACS

The exchange of information between a Radiology Information System (RIS) and a PACS is essential to optimizing the utility of a PACS. Some of the benefits awarded by implementing an interface include a reduction or elimination of repetitious data entry, the availability of more accurate information on the PACS, a reduction in workload for the technologists, registration clerks, transcriptionists, etc, and the availability of more accurate data for automating the PACS. This paper discusses the Georgetown experience of interfacing an HIS/RIS and PACS, by describing the development of the interface and its impact on clinical operations.
An algorithm for optimal partitioning of data on an interval

Many signal processing problems can be solved by maximizing the fitness of a segmented model over all possible partitions of the data interval. This letter describes a simple but powerful algorithm that searches the exponentially large space of partitions of N data points in time O(N/sup 2/). The algorithm is guaranteed to find the exact global optimum, automatically determines the model order (the number of segments), has a convenient real-time mode, can be extended to higher dimensional data spaces, and solves a surprising variety of problems in signal detection and characterization, density estimation, cluster analysis, and classification.
Advanced UVOIR Mirror Technology Development for Very Large Space Telescopes

Objective of this work is to define and initiate a long-term program to mature six inter-linked critical technologies for future UVOIR space telescope mirrors to TRL6 by 2018 so that a viable flight mission can be proposed to the 2020 Decadal Review. (1) Large-Aperture, Low Areal Density, High Stiffness Mirrors: 4 to 8 m monolithic & 8 to 16 m segmented primary mirrors require larger, thicker, stiffer substrates. (2) Support System:Large-aperture mirrors require large support systems to ensure that they survive launch and deploy on orbit in a stress-free and undistorted shape. (3) Mid/High Spatial Frequency Figure Error:A very smooth mirror is critical for producing a high-quality point spread function (PSF) for high-contrast imaging. (4) Segment Edges:Edges impact PSF for high-contrast imaging applications, contributes to stray light noise, and affects the total collecting aperture. (5) Segment-to-Segment Gap Phasing:Segment phasing is critical for producing a high-quality temporally stable PSF. (6) Integrated Model Validation:On-orbit performance is determined by mechanical and thermal stability. Future systems require validated performance models. We are pursuing multiple design paths give the science community the option to enable either a future monolithic or segmented space telescope.
How long does it take to catch a wild kangaroo

The discrete logarithm problem asks to solve for the exponent x, given the generator g of a cyclic group G and an element h∈ G such that gx=h. We give the first rigorous proof that Pollard's Kangaroo method finds the discrete logarithm in expected time (3+o(1))√{b-a} for the worst value of x∈[a,b], and (2+o(1))√b-a when x∈uar[a,b]. This matches the conjectured time complexity and, rare among the analysis of algorithms based on Markov chains, even the lead constants 2 and 3 are correct.
Nonparametric Estimation of Expected Shortfall

The expected shortfall is an increasingly popular risk measure in financial risk management and it possesses the desired sub-additivity property, which is lacking for the value at risk (VaR). We consider two nonparametric expected shortfall estimators for dependent financial losses. One is a sample average of excessive losses larger than a VaR. The other is a kernel smoothed version of the first estimator (Scaillet, 2004 Mathematical Finance), hoping that more accurate estimation can be achieved by smoothing. Our analysis reveals that the extra kernel smoothing does not produce more accurate estimation of the shortfall. This is different from the estimation of the VaR where smoothing has been shown to produce reduction in both the variance and the mean square error of estimation. Therefore, the simpler ES estimator based on the sample average of excessive losses is attractive for the shortfall estimation.
Gold(I)-Catalyzed Regioselective Cyclizations of Silyl Ketene Amides and Carbamates with Alkynes

The gold(I)-catalyzed regioselective cyclizations of silyl ketene amides or carbamates with alkynes were utilized to construct cyclopentanes or dehydro-δ-lactams.
Fully confined photonic band gap and guided modes in a two-dimensional photonic crystal slab

Summary form only given. As an optical analog to electronic crystals, the photonic crystal (PC) promises a revolution in the photonic world similar to the electronic revolution created by the electronic band gap engineering in semiconductors. A two-dimensional PC has the advantage of being easier to fabricate at optical wavelength (/spl lambda/) compared with a 3D PC. However, the light leakage in the vertical direction has been the main problem for using a 2D PC in opto-electronic application. In the study, we solve this problem by combining a traditional 2D PC with a strong vertical index guiding between the waveguide layer (GaAs) and the cladding layer (Al/sub x/O/sub y/).
Pulsed current-mode signaling for nearly speed-of-light intrachip communication

In this paper, we describe the design of on-chip repeater-less interconnects with nearly speed-of-light latency. Sharp current-pulse data transmission is used to modulate transmitter energy to higher frequencies, where the effect of wire inductance is maximized, allowing the on-chip wires to function as transmission lines with considerably reduced dispersion. A prototype 8-Gb/s serial link employing this pulsed current-mode signaling in a 0.18-/spl mu/m CMOS process is described and measured.
CCC–N-heterocyclic carbene pincer complexes: Synthesis, characterization and hydroamination activity of a hafnium complex

Abstract Our methodology for the stoichiometric preparation of CCC–NHC pincer complexes of Zr has been extended to Hf. The CCCBu–NHC pincer Hf complex has been characterized by X-ray crystal structure analysis. Catalytic activity in the intramolecular hydroamination/cyclization of unactivated alkenes is reported and compared to the recently reported Zr analog. An improved, scaled-up CuO-catalyzed aryl amination of 1,3-dibromobenzene and an improved salt formation methodology for preparation of bis(butyl-imidazolium)benzene are reported also.
Thermal analysis of the APT power coupler and similarities to superconducting magnet current leads

A detailed thermal analysis has been performed on the 210 kW, 700 MHz RF power coupler (PC) which transfers microwave energy from high power klystrons to the superconducting (SC) resonant cavities for the acceleration of protons. The work is part of the design for Accelerator Production of Tritium funded by the US Department of Energy. The PC is a co-axial design with the RF power transmitted in the annular region between two concentric cylinders. The PC provides a thermal connection from room temperature to superconducting niobium operating at 2.15 K. Heat transfer mechanisms considered are conduction, infra-red radiation, RF joule heating in normal and superconducting materials, and, forced and natural convection cooling. The objective of the thermal analysis is to minimize the required refrigeration power subject to manufacturability and reliability concerns. The problem is reminiscent of the optimization of superconducting magnet leads. The similarities and differences in the results between SC leads and PCs are discussed as well as the critical parameters in the PC optimization.
Global biomass burning - Atmospheric, climatic, and biospheric implications

Topics discussed at the March 1990 American Geophysical Union's Conference on biomass burning which was attended by more than 175 participants representing 19 countries are presented. Conference highlights include discussion of remote sensing data concerning biomass burning (BB), gaseous and particle emissions resulting from BB in the tropics, BB in temperate and boreal ecosystems, the historic and prehistoric perspectives on BB, BB and global budgets for carbon, nitrogen, and oxygen, and the BB and the greenhouse effect. Global estimates of annual amounts of biomass burning and of the resulting release of carbon to the atmosphere and the mean gaseous emission ratios for fires in wetlands, chaparral, and boreal ecosystems are given. An overview is presented of some conference discussions including global burning from 1850-1980, the global impact of biomass burning, the great Chinese/Soviet fire of 1987, and burning and biogenic emissions.
Energy-Efficient Path Planning for Solar-Powered Mobile Robots

We explore the problem of energy-efficient, time-constrained path planning of a solar powered robot embedded in a terrestrial environment. Because of the effects of changing weather conditions, as well as sensing concerns in complex environments, a new method for solar power prediction is desired. We present a method that uses Gaussian Process regression to build a solar map in a data-driven fashion. With this map, we perform energy-optimal path planning using a dynamic programming algorithm. We validate our map construction and path planning algorithms with outdoor experiments, and perform simulations on our solar maps to determine under which conditions the weight of added solar panels is worthwhile for a mobile robot.
Central Precocious Puberty: Update on Diagnosis and Treatment

Central precocious puberty (CPP) is characterized by the same biochemical and physical features as normally timed puberty but occurs at an abnormally early age. Most cases of CPP are seen in girls, in whom it is usually idiopathic. In contrast, ~50 % of boys with CPP have an identifiable cause. The diagnosis of CPP relies on clinical, biochemical, and radiographic features. Untreated, CPP has the potential to result in early epiphyseal fusion and a significant compromise in adult height. Thus, the main goal of therapy is preservation of height potential. The gold-standard treatment for CPP is gonadotropin-releasing hormone (GnRH) analogs (GnRHa). Numerous preparations with a range of delivery systems and durations of action are commercially available. While the outcomes of patients treated for CPP have generally been favorable, more research about the psychological aspects, optimal monitoring, and long-term effects of all forms of GnRHa treatment is needed. Several potential therapeutic alternatives to GnRHa exist and await additional investigation.
Managing Data Retention Policies at Scale

Regulatory policies such as EU privacy, HIPAA, and PCI-DSS place requirements on availability, integrity, migration, retention, and access of data, and compliance with such policies on stored data remains a key hurdle to cloud computing. This paper proposes a policy management service that offers scalable management of data retention policies attached to data objects stored in a cloud environment. An important aspect of any data retention service is permanent deletion of data. We achieve secure data deletion by encrypting the data when stored, and then deleting the encryption key at a specified retention time. Thus, we effectively delete the data object and its copies stored in online and offline environments. Our data retention service includes a highly scalable and secure encryption key store to manage encryption keys on-line. A prototype deployed on a 16-machine Linux cluster currently supports 56 MB/sec for encryption, 76 MB/sec for decryption, 31,000 retention policies/sec read and 15,000 retention policies/sec write.
Properties of disk scheduling policies in multiprogrammed computer systems

The subject of scheduling for movable head rotating storage devices, i.e., disk-like devices, has been discussed at length in recent literature. The early scheduling models were developed by Denning, Frank, and Weingarten. Highly theoretical models have been set forth recently by Manocha, and a comprehensive simulation study has been reported on by Teorey and Pinkerton.
Combined analog/digital computing elements

This paper describes a number of computing elements whose accuracy is considerably higher than that of comparable analog devices and whose speed of operation is considerably faster than that of comparable digital circuits. These elements employ both analog and digital computing techniques. The input and output signals of these hybrid computing devices are presented by two quantities, the most significant part by a parallel binary number and the least significant part by an analog voltage.The hybrid multiplier consists of a relatively simple digital multiplier, three D/A converters, a very simple analog multiplier, and a summing and comparison circuit. An accuracy of 1 part in 104 and a bandwidth of 1KC is possible with a relatively simple circuit. The accuracy can be expanded theoretically as high as desired at the cost of additional equipment.The hybrid integrator consists of an accumulating register, a variable amplitude sawtooth generator, a simple analog integrator and a summing and comparison circuit. Its dynamic range and accuracy are limited only by the number of digits used in the R-register.The hybrid function generator consists of a diode decoding matrix, a diode translation matrix, two D/A converters and a summing and comparison circuit. A repeatability of 1 part in 104 and a bandwidth of 1KC is easily possible.There are no A/D converters, no external storage means, no timing circuits (except clock frequency for integrator), no controls to adjust, and no temperature-sensitive circuits in a system using these hybrid computing elements.