cssi/SciSciGPT-SciSciNet huggingface dataset:
Technological innovation and market turbulence: The dot-com experience

Abstract This paper explains market turbulence, such as the recent dot-com boom/bust cycle, as equilibrium industry dynamics driven by the synergy between new and existing technologies. When a major technological innovation arrives, a wave of new firms implement the innovation and enter the market. However, if the innovation complements existing technology, some new entrants later will be forced out as more and more incumbent firms succeed in adopting the innovation. It is argued that the diffusion of Internet technology among traditional brick-and-mortar firms was indeed the driving force behind the rise and fall of dot-coms as well as the sustained growth of e-commerce. Systematic empirical evidence from retail and banking industries supports the theoretical findings.
Asymptotic expansions for the sojourn time distribution in the M / G /1-PS queue

We consider the M/G/1 queue with a processor sharing server. We study the conditional sojourn time distribution, conditioned on the customer’s service requirement, as well as the unconditional distribution, in various asymptotic limits. These include large time and/or large service request, and heavy traffic, where the arrival rate is only slightly less than the service rate. Our results demonstrate the possible tail behaviors of the unconditional distribution, which was previously known in the cases G = M and G = D (where it is purely exponential). We assume that the service density decays at least exponentially fast. We use various methods for the asymptotic expansion of integrals, such as the Laplace and saddle point methods.
List decoding for nested lattices and applications to relay channels

We demonstrate a decoding scheme for nested lattice codes which is able to decode a list of a particular size which contains the transmitted codeword with high probability. This list decoder is analogous to that used in random coding arguments in achievability schemes of relay channels, and allows for the effective combination of information from the relay and source node. Using this list decoding result, we demonstrate 1) that lattice codes may achieve the capacity of the physically degraded AWGN relay channel, 2) an achievable rate region for the two-way relay channel with direct links using lattice codes, and 3) that we may improve the constant gap to capacity for specific cases of the two-way relay channel with direct links.
Asymmetric Methods for the Synthesis of Flavanones, Chromanones, and Azaflavanones.

Flavanones, chromanones, and related structures are privileged natural products that display a wide variety of biological activities. Although flavanoids are abundant in nature, there are a limited number of available general and efficient synthetic methods for accessing molecules of this class in a stereoselective manner. Their structurally simple architectures belie the difficulties involved in installation and maintenance of the stereogenic configuration at the C2 position, which can be sensitive and can undergo epimerization under mildly acidic, basic, and thermal reaction conditions. This review presents the methods currently used to access these related structures. The synthetic methods include manipulation of the flavone/flavanone core, carbon-carbon bond formation, and carbon–heteroatom bond formation.
The Formation and Evolution of Intracluster Light

Using N-body simulations, we have modeled the production and evolution of diffuse, low surface brightness intracluster light (ICL) in three simulated galaxy clusters. Using an observational definition of ICL to be luminosity at a surface brightness µV> 26.5 mag/arcsec 2 , we have found that the fraction of cluster luminosity contained in ICL generally increases as clusters evolve, although there are large deviations from this trend over short timescales, including sustained periods of decreasing ICL luminosity. Most ICL luminosity increases come in short, discrete events which are highly correlated with group accretion events within the cluster. In evolved clusters we find that 10 - 15% of the clusters’ luminosity is at ICL surface brightness. The morphological structure of the ICL changes with time, evolving from a complex of filaments and smallscale, relatively high surface brightness features early in a cluster’s history, to a more diffuse and amorphous cluster-scale ICL envelope at later times. Finally, we also see a correlation between the evolution of ICL at different surface brightnesses, including a time delay between the evolution of faint and extremely faint surface brightness features which is traced to the differing dynamical timescales in the group and cluster environment. Subject headings: galaxies: clusters: general — galaxies: evolution — galaxies : interactions — galaxies: kinematics and dynamics — methods: N-body simulations
Outcomes following negative prostate biopsy for patients with persistent disease after radiotherapy for prostate cancer.

PURPOSE: When faced with biochemical recurrence after definitive radiotherapy for prostate cancer, clinicians must determine whether the recurrence is local or systemic. Post radiotherapy prostate biopsies to detect persistent local disease are difficult to interpret histopathologically and are subject to sampling error. Our study examines outcomes for patients with a negative prostate biopsy performed for rising prostate-specific antigen (PSA) levels after prostate radiation. MATERIALS AND METHODS: We performed a retrospective review of 238 prostate cancer patients with a negative biopsy following definitive radiotherapy. Seventy-five of these patients had biochemical recurrence at the time of biopsy. A negative biopsy was defined as the absence of prostate cancer without radiation-treatment effect in the specimen. RESULTS: Patients underwent biopsy at a mean of 41 months after the completion of radiation. They had a mean PSA of 6. Patients were followed for an average of 63 months. Thirty-two patients (43%) developed metastasis, and 11 (15%) died of prostate cancer despite a negative post-radiation biopsy. Five of nine patients (56%) with sequential biopsies had a positive second biopsy. CONCLUSIONS: Patients with PSA recurrence and a negative post-radiation biopsy have a high chance of persistent local disease, progression, and death from prostate cancer. Furthermore, an initial negative biopsy does not rule-out local recurrence. Patients with biochemical recurrence after radiotherapy for prostate cancer need to be evaluated earlier for local recurrence.
Optimal Control of Sensor Threshold for Autonomous Wide Area Search Munitions

The optimal employment of autonomous wide area search munitions is addressed. The scenario considered involves an airborne munition searching a battle space for stationary targets in the presence of false targets. Targets are modelled with uniform, Poisson, and normal distributions. False targets are modelled with Poisson distributions. All relevant parameters can be extracted from intelligence information on the enemy’s order of battle and the sensor performance specification. Analytic weapon effectiveness measures are derived using applied probability theory. The effectiveness measures derived in this paper handle time-varying parameters which characterize the battle space environment and the performance of the munition’s sensor. This allows the formulation and solution of optimization problems that maximize the probability of a target attack while at the same time constraining the probability of a false target attack. Optimal schedules for controlling the sensor threshold during the flight are derived and compared to the optimal constant-threshold results. An increase in weapon effectiveness is demonstrated when the sensor threshold is dynamically controlled during the flight.
Evolution of tubewell ownership and production in the North China Plain

The overall aim of the present paper is to better understand the evolution of tubewell ownership in the North China Plain, especially focusing on the factors that determine ownership and its effect on production. Based on a random sample of 30 villages in three counties in the Hai River Basin, our results show that collectively owned tubewells have been gradually privatised. The analyses demonstrate that increasing water and land scarcity and policy intervention (mainly fiscal and financial subsidies for tubewell investment) leads to the observed shifts in tubewell ownership patterns. The results also show that the privatisation of tubewells has affected cropping patterns in the North China Plain. When villages shift towards private tubewells, farmers move into more water-sensitive and high-value crops. Privatisation, however, has no negative effect on crop productivity in the present sample. Importantly, the evolution of tubewell ownership in the villages studied does not accelerate the fall of the groundwater table.
Mining coherent gene clusters from gene-sample-time microarray data

Extensive studies have shown that mining microarray data sets is important in bioinformatics research and biomedical applications. In this paper, we explore a novel type of gene-sample-time microarray data sets, which records the expression levels of various genes under a set of samples during a series of time points. In particular, we propose the mining of coherent gene clusters from such data sets. Each cluster contains a subset of genes and a subset of samples such that the genes are coherent on the samples along the time series. The coherent gene clusters may identify the samples corresponding to some phenotypes (e.g., diseases), and suggest the candidate genes correlated to the phenotypes. We present two efficient algorithms, namely the Sample-Gene Search and the Gene-Sample Search, to mine the complete set of coherent gene clusters. We empirically evaluate the performance of our approaches on both a real microarray data set and synthetic data sets. The test results have shown that our approaches are both efficient and effective to find meaningful coherent gene clusters.
Topological insulating phases of non-Abelian anyonic chains

Boundary conformal field theory is brought to bear on the study of topological insulating phases of non-Abelian anyonic chains. These phases display protected anyonic end modes. We consider spin-1/2 su(2)${}_{k}$ chains at any level $k$, focusing on the most prominent examples: the case $k=2$ describes Ising anyons (equivalent to Majorana fermions) and $k=3$ corresponds to Fibonacci anyons. The method we develop is quite general and rests on a deep connection between boundary conformal field theory and topological symmetry. This method tightly constrains the nature of the topological insulating phases of these chains for general $k$. Emergent anyons which arise at domain walls are shown to have the same braiding properties as the physical quasiparticles. This suggests a ``solid-state'' topological quantum computation scheme in which emergent anyons are braided by tuning the couplings of non-Abelian quasiparticles in a fixed network.
Synthesis of a Thiophene‐Based Nonlinear Optical Chromophore

Abstract This report details an eight‐step synthesis of the thiophene‐type nonlinear optical chromophore 1 in 38% overall yield. Only one early step required chromatography.
Is there Complete, Partial, or No Recovery from Childhood Malnutrition?: Empirical Evidence from Indonesia

This article uses a dynamic panel data model to identify the impact of early nutritional deficiencies on individuals’ health status in later ages. We find that poor nutrition at young ages causes some, but not severe retardation in the growth of future height indicating partial recovery from chronic malnourishment. The results also indicate that – younger children, stunted children, and children who live in communities with six or more health posts exhibit larger recovery. The estimation strategy used here is especially attractive as it relies on weaker stochastic assumptions compared to earlier work in the literature.
A direct entry to the 1-methoxyindole skeleton and to the corresponding indoles by a novel rearrangement: general syntheses of substituted 1-methoxyindoles☆

A short and efficient route to 1-methoxyindoles via a novel rearrangement is disclosed. This route involves only three steps from commercially available nitro compounds. The methodology is also generalized with a variety of examples to afford a series of 2-substituted-1-methoxyindoles possessing an electron-withdrawing group at position 3. In addition, a 1-methoxyindole compound 10 was converted to the corresponding indole 11 under mild conditions thereby constituting a new synthesis of substituted indoles.
Dynamic Modeling of Discrete Biologics for Active Sonar Simulation

In this paper, we propose a simple model for simulating the group dynamics of aggregate, discrete biologics in active undersea sonar. Using a Lagrangian representation, group behavior is modeled by a set of Newtonian forces and stochastic perturbations on a collection of point masses. Interactions comprise a grouping force, which gives a characteristic separation distance, and an arrayal force, which tends to align the velocities of the group's constituents. The model is similar to previous attempts to model fish schools but contains only six parameters: three that are physical and three that are behavioral in nature. We characterize the group dynamics in terms of their statistical and asymptotic properties and study these as a function of the model parameters. The key result is a set of predictions for the asymptotic speed and separation distance in terms of the model parameters.
Adaptive Alternating Minimization Algorithms

The classical alternating minimization (or projection) algorithm has been successful in the context of solving optimization problems over two variables. The iterative nature and simplicity of the algorithm has led to its application in many areas such as signal processing, information theory, control, and finance. A general set of sufficient conditions for the convergence and correctness of the algorithm are known when the underlying problem parameters are fixed. In many practical situations, however, the underlying problem parameters are changing over time, and the use of an adaptive algorithm is more appropriate. In this paper, we study such an adaptive version of the alternating minimization algorithm. More precisely, we consider the impact of having a slowly time-varying domain over which the minimization takes place. As a main result of this paper, we provide a general set of sufficient conditions for the convergence and correctness of the adaptive algorithm. Perhaps somewhat surprisingly, these conditions seem to be the minimal ones one would expect in such an adaptive setting. We present applications of our results to adaptive decomposition of mixtures, adaptive log-optimal portfolio selection, and adaptive filter design.
A Study of Organizational Effectiveness and its Predictors

Some authors have argued that research on organizational effectiveness should cease. This study demonstrates why organizational effectiveness studies are crucial in certain types of organizations, and it points out how many of the weaknesses and criticisms of past investigations can be addressed. The results of this study of 29 organizations indicate that certain managerial strategies are strongly associated with high static scores and with improving effectiveness over time. Managerial strategies, in fact, were found to be more important than structure, demographics, finances, and other factors. Proactive strategies and those with an external emphasis are more successful than internal and reactive strategies. Managerial strategies that are multifaceted are more likely to lead to effectiveness than monolithic strategies.
Sensitivity of Tropical Cyclone Intensity to Ventilation in an Axisymmetric Model

The sensitivity of tropical cyclone intensity to ventilation of cooler, drier air into the inner core is examined using an axisymmetric tropical cyclone model with parameterized ventilation. Sufficiently strong ventilation induces cooling of the upper-level warm core, a shift in the secondary circulation radially outward, and a decrease in the simulated intensity. Increasing the strength of the ventilation and placing the ventilation at middle to lower levels results in a greater decrease in the quasi-steady intensity, whereas upper-level ventilation has little effect on the intensity. For strong ventilation, an oscillatory intensity regime materializes and is tied to transient convective bursts and strong downdrafts into the boundary layer. The sensitivity of tropical cyclone intensity to ventilation can be viewed in the context of the mechanical efficiency of the inner core or a modified thermal wind relation. In the former, ventilation decreases the mechanical efficiency, as the generation of available potential energy is wasted by entropy mixing above the boundary layer. In the latter, ventilation weakens the eyewall entropy front, resulting in a decrease in the intensity by thermal wind arguments. The experiments also support the existence of a threshold ventilation beyond which a tropical cyclone cannot be maintained. Downdrafts overwhelm surface fluxes, leading to a precipitous drop in intensity and a severe degradation of structure in such a scenario. For a given amount of ventilation below the threshold, there exists a minimum initial intensity necessary for intensification to the quasi-steady intensity.
The operating performance of firms conducting seasoned equity offerings

Recent studies have documented that firms conducting seasoned equity offerings have inordinately low stock returns during the five years after the offering, following a sharp run-up in the year prior to the offering. This article documents that the operating performance of issuing firms shows substantial improvement prior to the offering, but then deteriorates. The multiples at the time of the offering, however, do not reflect an expectation of deteriorating performance. Issuing firms are disproportionately high-growth firms, but issuers have much lower subsequent stock returns than nonissuers with the same growth rate. SEVERAL RECENT EMPIRICAL STUDIES have documented the poor stock market performance of firms conducting seasoned equity offerings (SEOs) in the United States and other countries.1 Loughran and Ritter (1995) report that the average raw return for issuing firms is only 7 percent per year during the five years after the offering, compared to 15 percent per year for nonissuing firms of the same market capitalization. These low postissue returns follow extremely high returns in the year prior to the offering: 72 percent on average.2 This article links the stock price performance of these issuing firms to their operating performance, and in so doing, addresses four questions: 1) Does the postissue operating performance of issuers deteriorate relative to comparable nonissuing firms? 2) Are the patterns for large issuers different from those for small issuers? 3) Do the capital expenditure decisions of issuers suggest that the managers are just as overoptimistic as investors are? 4) Given that issuing firms tend to be rapidly growing, and rapidly growing firms display strong
Relating amino acid sequence to phenotype: analysis of peptide-binding data.

SUMMARY. We illustrate data analytic concerns that arise in the context of relating genotype, as represented by amino acid sequence, to phenotypes (outcomes). The present application examines whether peptides that bind to a particular major histocompatibility complex (MHC) class I molecule have characteristic amino acid sequences. However, the concerns identified and addressed are considerably more general. It is recognized that simple rules for predicting binding based solely on preferences for specific amino acids in certain (anchor) positions of the peptide's amino acid sequence are generally inadequate and that binding is potentially influenced by all sequence positions as well as between-position interactions. The desire to elucidate these more complex prediction rules has spawned various modeling attempts, the shortcomings of which provide motivation for the methods adopted here. Because of (i) this need to model between-position interactions, (ii) amino acids constituting a highly (20) multilevel unordered categorical covariate, and (iii) there frequently being numerous such covariates (i.e., positions) comprising the sequence, standard regression/classification techniques are problematic due to the proliferation of indicator variables required for encoding the sequence position covariates and attendant interactions. These difficulties have led to analyses based on (continuous) properties (e.g., molecular weights) of the amino acids. However, there is potential information loss in such an approach if the properties used are incomplete and/or do not capture the mechanism underlying association with the phenotype. Here we demonstrate that handling unordered categorical covariates with numerous levels and accompanying interactions can be done effectively using classification trees and recently devised bump-hunting methods. We further tackle the question of whether observed associations are attributable to amino acid properties as well as addressing the assessment and implications of between-position covariation.
Analysis of White Dwarfs with Strange-Matter Cores

We summarize masses and radii for a number of white dwarfs as deduced from a combination of proper motion studies, Hipparcos parallax distances, effective temperatures and binary or spectroscopic masses. A puzzling feature of these data, however, is that some stars appear to have radii which are significantly smaller than that expected for a standard electron-degenerate white-dwarf equations of state. We construct a projection of white-dwarf radii for fixed effective mass and conclude that there is at least marginal evidence for bimodality in the radius distribution for white dwarfs. We argue that if such compact white dwarfs exist it is unlikely that they contain an iron core. We propose an alternative of strange-quark matter within the white-dwarf core. We also discuss the impact of the so-called color-flavour-locked (CFL) state in strange-matter core associated with color superconductivity. We show that the data exhibit several features consistent with the expected mass-radius relation of strange dwarfs. We identify eight nearby white dwarfs which are possible candidates for strange-matter cores and suggest observational tests of this hypothesis.
The Corporate Governance of Banks - a concise discussion of concepts and evidence

The author examines the corporate governance of banks. When banks efficiently mobilize and allocate funds, this lowers the cost of capital to firms, boosts capital formation, and stimulates productivity growth. So, weak governance of banks reverberates throughout the economy with negative ramifications for economic development. After reviewing the major governance concepts for corporations in general, the author discusses two special attributes of banks that make them special in practice: greater opaqueness than other industries and greater government regulation. These attributes weaken many traditional governance mechanisms. Next, he reviews emerging evidence on which government policies enhance the governance of banks and draws tentative policy lessons. In sum, existing work suggests that it is important to strengthen the ability and incentives of private investors to exert governance over banks rather than to rely excessively on government regulators. These conclusions, however, are particularly tentative because more research is needed on how legal, regulatory, and supervisory policies influence the governance of banks.
A versatile synthesis of hydroxy-9,10-anthraquinone-2-carboxylic acids.

Abstract Islandicin, a mould metabolite, can be synthesised in a few, robust, high yielding steps. This procedure can be further elaborated to give a variety of hydroxy-9,10-anthraquinone-2-carboxylic acids.
'Schemes of Practical Utility': Entrepreneurship and Innovation Among 'Great Inventors' in the United States, 1790-1865

The growth in inventive activity during early American industrialization is explored by examining the careers of 160 inventors credited with important technological discoveries. Analysis of biographical information and complete patent histories through 1865 indicates that these "great inventors" were entrepreneurial and responded systematically to market demand. Their inventions were procyclical and originated disproportionately from localities linked with extensive markets. Although unexceptional in terms of schooling or technical skills, they vigorously pursued the returns to their inventions, redirected their inventive activity to meet emerging needs, and were distinguished by high geographical mobility toward districts conducive to invention and its commercialization. A central and long-standing question about the process of economic growth is the extent to which technical change responds to market forces or is otherwise endogenously determined. Some scholars believe that the timing of important inventions is typically due to chance or to the logical evolution of technical knowledge, and depict the individuals responsible as geniuses or eccentrics inspired by motives other than material gain. Even when conceding that incremental improvements, or "microinventions," might be induced by material incentives, they continue to hold that important discoveries, or "macroinventions," are largely exogenous with respect to market demand.' An alternative perspective regards all inventions as probabilistic outcomes of investments in inventive activity that are influenced, like any other investment, by an assessment of the potential financial returns. In this view, circumstances that enhance the expected net return to inventive activity, such as the characteristic expansion of markets during the initial
Adiabatic invariance for spatially dependent accelerating structures

The adiabatic dynamics of charged particles in accelerating structures is significantly altered if these structures vary in space rather than in time. Spatial variation occurs in, for example, free-electron lasers and radio-frequency quadrupoles. The adiabatic invariants for slow temporal and slow spatial variations differ. This causes the longitudinal emittance of adiabatically trapped beams to differ in the two cases. The number of particles trapped in each accelerating bucket also differs. Analytic and numerical results are presented to clarify these ideas. >
Synthetic Peptides for Production of Antibodies that Recognize Intact Proteins

Antibodies that recognize intact proteins can be produced through the use of synthetic peptides based on short stretches of the protein sequence, without first having to isolate the protein. The steps to produce an effective antibody include: (1) designing the peptide sequence based on the sequence of the protein; (2) synthesizing the peptide; (3) preparing the immunogen either by coupling the synthetic peptide to a carrier protein or through the use of a multiple antigenic peptide (MAP); (4) immunizing the host animal; (5) assaying antibody titer in the host animal's serum; and (6) obtaining the antiserum and/or isolating the antibody. This unit covers steps 1 and 3. Once the coupling procedure has been performed, it is possible to determine the approximate degree of coupling by amino acid analysis. Also presented are methods for assaying free sulfhydryl content and for reducing disulfide bonds in synthetic peptides.
Chiral molecular tweezers.

In this Account, a summary of our work on the synthesis and chemistry of chiral molecular tweezers and certain related species is presented. The framework around which the structures to be discussed were built was Kagan's ether, a short history of which will be given. Chiral molecular tweezers of various sizes were constructed and shown to exhibit binding to various π acids. An analysis of chiral recognition was performed using variable temperature chiral high-performance liquid chromatography. It was shown that the chiral discrimination was essentially enthalpic in nature. Other forays into the chemistry of Kagan's ether analogues have also been made through the synthesis of a chiral catalyst and a chiral molecular square.
Real Exchange Rate Behavior Under Alternative International Monetary Regimes: Interwar Evidence

UNIVERSITY OF CALIFORNIA, BERKELEY Department of Economics Berkeley, California Working Paper 8755 REAL EXCHANGE RATE BEHAVIOR UNDER ALTERNATIVE INTERNATIONAL MONETARY REGIMES: INTERWAR EVIDENCE Barry Eichengreen September Key words: exchange rate *Prepared for the European Economic Association meetings, Copenhage: August 22-24, 1987. I thank Jeffrey Frankel, Francesco Giavazzi, and Lars Jonung for helpful comments. JEL Classification:
Catalytic asymmetric allylic alkylation employing heteroatom nucleophiles: a powerful method for C–X bond formation

Metal catalyzed asymmetric allylic alkylation (AAA) reactions have been an extensively studied and fruitful area of research in organic chemistry. The use of heteroatom-centered nucleophiles in this reaction is a powerful method for asymmetric C–X (X = heteroatom) bond formation. This perspective summarizes developments and applications of metal catalyzed AAA reactions employing heteroatom nucleophiles.
Effect of Barium Titanate on Microstructural Evolution and Properties of Lead Zinc Magnesium Niobate Ceramics

BaTiO3 (BT) addition vastly alters the dielectric behavior of lead zinc magnesium niobate (PZMN) relaxor ferroelectrics. Heat treatment, including the sintering process, influences the dielectric properties through changes in the distribution of heterogeneous compositions and in the extent of diffused phase transition. With more than 15 mol% BaTiO3 addition, two cubic phases composed of Ba-rich and Ti-rich PZMN substances exist. The destruction of the BaTiO3 phase and reconstruction of Ba-rich and Ti-rich regions are initiated during heat treatment, and the extent of destruction and reconstruction determines the dielectric properties of the PZMN ceramics. The BT-rich PZMN phase, which occurs with higher BaTiO3 addition, plays a less important role in the present investigation.
Synthetic applications of tryptophan synthase

Abstract Tryptophan synthase catalyzes the final two steps in l -tryptophan synthesis in bacteria and plants. The α-subunit catalyzes the reversible retroaldol cleavage of indole-3-glycerol phosphate to give indole and d -glyceraldehyde-3-phosphate, and the β-subunit catalyzes the condensation of indole with l -serine to give l -tryptophan. The α-reaction has been used for the synthesis of indole-3-glycerol phosphate, but has not been investigated extensively for synthesis of analogues. The β-reaction has been used for the preparation of a wide range of analogues of l -tryptophan, including chloro and azido benzene ring-substituted tryptophans, as well as aza, thia, and selena heterocyclic analogues. In addition, S -alkyl and S -aryl cysteines, Se -alkyl selenocysteines, as well as β-nitrogen substituted alanines have been prepared.
Synchronized SETI-the case for "opposition".

If the signals being sought in search for extraterrestrial intelligence (SETI) programs exist but are brief (for example, they are produced intermittently to conserve energy), then it is essential to know when these signals will arrive at the Earth. Different types of transmitter/receiver synchronization schemes are possible, which vary in the relative amount of effort required by the transmitter and the receiver. The case is made for a scheme that is extremely simple for the receiver: Make observations of a target when it is at maximum angular distance from the Sun (i.e., "opposition"). This strategy requires that the transmitter has accurate knowledge of the distance and proper motion of the Sun and the orbit of the Earth. It is anticipated that within the next 10-20 years it will be possible to detect directly nearby extrasolar planets of approximately terrestrial mass. Since extraterrestrial transmitters are expected to have significantly more advanced technology, it is not unreasonable to expect that...
Annealing a Follow-up Program: Improvement of the Dark Energy Figure of Merit for Optical Galaxy Cluster Surveys

The precision of cosmological parameters derived from galaxy cluster surveys is limited by uncertainty in relating observable signals to cluster mass. We demonstrate that a small mass-calibration follow-up program can significantly reduce this uncertainty and improve parameter constraints, particularly when the follow-up targets are judiciously chosen. To this end, we apply a simulated annealing algorithm to maximize the dark energy information at fixed observational cost, and find that optimal follow-up strategies can reduce the observational cost required to achieve a specified precision by up to an order of magnitude. Considering clusters selected from optical imaging in the Dark Energy Survey, we find that approximately 200 low-redshift X-ray clusters or massive Sunyaev-Zel'dovich clusters can improve the dark energy figure of merit by 50%, provided that the follow-up mass measurements involve no systematic error. In practice, the actual improvement depends on (1) the uncertainty in the systematic error in follow-up mass measurements, which needs to be controlled at the 5% level to avoid severe degradation of the results and (2) the scatter in the optical richness-mass distribution, which needs to be made as tight as possible to improve the efficacy of follow-up observations.
Detecting gear tooth fatigue cracks in advance of complete fracture

Abstract : Results of using vibration based methods to detect gear tooth fatigue cracks are presented. An experimental test rig was used to fail a number of spur gear specimens through bending fatigue. The gear tooth fatigue crack in each test was initiated through a small notch in the fillet area of a tooth on the gear. The primary purpose of these tests was to verify analytical predictions of fatigue crack propagation direction and rate as a function of gear rim thickness. The vibration signal from a total of three tests was monitored and recorded for gear fault detection research. The damage consisted of complete rim fracture on the two thin rim gears and single tooth fracture on the standard full rim test gear. Vibration-based fault detection methods were applied to the vibration signal both on-line and after the tests were completed. The objectives of this effort were to identify methods capable of detecting the fatigue crack, and determine how far in advance of total failure positive detection was given. Results showed that the fault detection methods failed to respond to the fatigue crack prior to complete rim fracture in the thin rim gear tests. In the standard full rim gear test all of the methods responded to the fatigue crack in advance of tooth fracture; however, only three of the methods responded to the fatigue crack in the early stages of crack propagation.
What I have learned by using chemical model systems to study biomolecular structure and interactions.

Chemical model systems provide valuable insights into biomolecular structure and interactions by allowing researchers to simplify, isolate, and manipulate aspects of the complex molecular machinery of living systems. This perspective describes my laboratory's design, synthesis, and study of chemical model systems that fold and self-assemble like proteins and elucidates the insights that have come from studying these systems. Many of these studies have focused on protein β-sheets, which exhibit fascinating intra- and intermolecular interactions and play important roles in protein folding, aggregation, and molecular recognition.
A variational approach to nonlinear dynamics of nanoscale surface modulations

Abstract In this paper, we propose a variational formulation to study the singular evolution equations that govern the dynamics of surface modulations on crystals below the roughening temperature. The basic idea of the formulation is to expand the surface shape in terms of a complete set of basis functions and to use a variational principle equivalent to the continuum evolution equations to obtain coupled nonlinear ordinary differential equations for the expansion coefficients. Unlike several earlier approaches that rely on ad hoc regularization procedures to handle the singularities in the evolution equations, the only inputs required in the present approach are the orientation dependent surface energies and the diffusion constants. The method is applied to study the morphological equilibration of patterned unidirectional and bidirectional sinusoidal modulations through surface diffusion. In the case of bidirectional modulations, particular attention is given to the analysis of the profile decay as a function of ratio of the modulating wavelengths in the coordinate directions. A key question that we resolve is whether the one-dimensional decay behavior is recovered as one of the modulating wavelengths of the two-dimensional profiles diverges, or whether one-dimensional decay has qualitatively distinct features that cannot be described as a limiting case of the two-dimensional behavior. In contrast to some earlier suggestions, our analytical and numerical studies clearly show that the former situation is true; we find that the one-dimensional profiles, like the highly elongated two-dimensional profiles, decay with formation of facets. While our results for the morphological equilibration of symmetric one-dimensional profiles are in agreement with the free-boundary formulation of Spohn, the present approach can also be used to study the evolution of asymmetric profile shapes where the free-boundary approach is difficult to apply. The variational method is also used to analyze the decay of unidirectional modulations in the presence of steps that arise in most experimental studies due to a small misorientation from the singular surface.
Mixtures of Gaussians and minimum relative entropy techniques for modeling continuous uncertainties

Problems of probabilistic inference and decision making under uncertainty commonly involve continuous random variables. Often these are discretized to a few points, to simplify assessments and computations. An alternative approximation is to fit analytically tractable continuous probability distributions. This approach has potential simplicity and accuracy advantages, especially if variables can be transformed first. This paper shows how a minimum relative entropy criterion can drive both transformation and fitting, illustrating with a power and logarithm family of transformations and mixtures of Gaussian (normal) distributions, which allow use of efficient influence diagram methods. The fitting procedure in this case is the well-known EM algorithm. The selection of the number of components in a fitted mixture distribution is automated with an objective that Wades off accuracy and computational cost.
Progress in parallelizing XOOPIC

Summary form only given. XOOPIC (object oriented particle in cell code for X11-based Unix workstations) is presently a serial 2d 3v particle-in-cell plasma simulation. The present effort focuses on using parallel and distributed processing to optimize the simulation for large problems. The benefits include increased capacity for memory intensive problems, and improved performance for processor-intensive problems.
Impact of Marketing Channels on Perceptions of Quality of Life and Profitability for Wisconsin’s Organic Vegetable Farmers

A recent increase in programs supporting the entry of organic farmers into direct market channels, such as farmers' markets and community-supported agriculture has occurred in the USA. In order to better implement these programs and to design better outreach and educational support activities for direct market farmers, understanding farmers’ perceptions of success in these marketing channels is valuable. To this goal, Wisconsin-certified organic vegetable farmers were surveyed in order to investigate the relationships between farm characteristics, marketing strategies, and farmer's perceptions of their profitability and quality of life. The data collected from this survey indicate that farmers selling into farmers' markets and through community-supported agriculture tend to be more likely to be dissatisfied with their profitability. Conversely, however, the survey data indicated that farmers selling into other markets, particularly wholesale markets and restaurants/institutions, are significantly more likely to be dissatisfied with their quality of life. Thus, it appears that farmers are making trade-offs with respect to entering markets that allow for greater financial rewards but may lead to a lower quality of life. These results point to the potential benefit of outreach efforts to assist farmers to increase their profitability in market channels that also provide a higher quality of life.
Fluctuation exchange analysis of superconductivity in the standard three-band CuO 2 model

The fluctuation exchange, or FLEX, approximation for interacting electrons is applied to study instabilities in the standard three-band model for ${\mathrm{CuO}}_{2}$ layers in the high-temperature superconductors. Both intraorbital and near-neighbor Coulomb interactions are retained. The filling dependence of the ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ transition temperature is studied in both the ``hole-doped'' and ``electron-doped'' regimes using parameters derived from constrained-occupancy density-functional theory for ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4}.$ The agreement with experiment on the overdoped hole side of the phase diagram is remarkably good, i.e., transitions emerge in the 40 K range with no free parameters. In addition the importance of the ``orbital antiferromagnetic,'' or flux phase, charge density channel is emphasized for an understanding of the underdoped regime.
The Tennessee Study of Class Size in the Early School Grades.

The Tennessee class size project is a three-phase study designed to determine the effect of smaller class size in the earliest grades on short-term and long-term pupil performance. The first phase of this project, termed Project STAR (for Student-Teacher Achievement Ratio), was begun in 1985, when Lamar Alexander was governor of Tennessee. Governor Alexander, who later served as secretary of education in the cabinet of President George Bush, had made education a top priority for his second term. The legislature and the educational community of Tennessee were mindful of a promising study of the benefits of small class size carried out in nearby Indiana, but were also aware of the costs associated with additional classrooms and teachers. Wishing to obtain data on the effectiveness of reduced class size before committing additional funds, the Tennessee legislature authorized this four-year study in which results obtained in kindergarten, first, second, and third grade classrooms of 13 to 17 pupils were compared with those obtained in classrooms of 22 to 25 pupils and in classrooms of this larger size where the teacher was assisted by a paid aide. Both standardized and curriculum-based tests were used to assess and compare the performance of some 6,500 pupils in about 330 classrooms at approximately 80 schools in the areas of reading, mathematics, and basic study skills. After four years, it was clear that smaller classes did produce substantial improvement in early learning and cognitive studies and that the effect of small class size on the achievement of minority children was initially about double that observed for majority children, but in later years, it was about the same. The second phase of the project, called the Lasting Benefits Study, was begun in 1989 to determine whether these perceived benefits persisted. Observations made as a part of this phase confirmed that the children who were originally enrolled in smaller classes continued to perform better than their grade-mates (whose school experience had begun in larger classes) when they were returned to regular-sized classes in later grades. Under the third phase, Project Challenge, the 17 economically poorest school districts were given small classes in kindergarten, first, second, and third grades. These districts improved their end-of-year standing in rank among the 139 districts from well below average to above average in reading and mathematics.(ABSTRACT TRUNCATED AT 400 WORDS)
Herbs commonly used by women: An evidence-based review

Abstract Objective: To review the evidence of herbs commonly used by women. Data Sources: Articles were located by searching Medline, Cochrane Database of Systemic Reviews, and the Combined Health Information Database and by hand searching the reference lists of recent systematic reviews. The databases were searched in January 2000 and October 2000 by using the Latin and common name of each herb. Methods Of Study Selection: Preference was given to randomized, placebo-controlled trials. When available, English language studies were reviewed. If not, data are presented from review articles that summarize the foreign study. Results: Many women use herbal therapies. In the United States, herbs are considered dietary supplements. The Food and Drug Administration (FDA) cannot remove them from the market unless they are proven unsafe. The herb industry plans to improve monitoring. Many prospective randomized controlled trials are being funded. Gingko biloba seems to slow the progression of dementia but increases the risk of bleeding. St John's Wort is efficacious for treating mild to moderate depression but has many drug interactions. Ginseng seems to improve well being in perimenopausal women, but it is often impure and has side effects and drug interactions. Garlic slightly lowers blood pressure and lipids. Echinacea slightly decreases the duration of colds but does not prevent them. Valerian is beneficial for insomnia, but there is no long-term safety data. Black cohosh may help the symptoms of perimenopause, and chasteberry may improve premenstrual syndrome. More study is needed on both herbs. Conclusion: Some herbs are medically useful, but the American public would benefit from increased regulation. Manufacturers should be able to ensure that herbs contain pure ingredients. Side effects and drug interactions should be listed. Well-designed studies are being conducted. The results will be helpful to physicians and patients when the clinical evidence becomes available.
The Demographic, Economic and Financial Determinants of International Remittances in Developing Countries

What causes developing countries to receive different levels of international remittances? This paper addresses this question by using new data on such variables as the skill composition of migrants, poverty, and interest and exchange rates to examine the determinants of remittances. The paper finds that the skill composition of migrants does matter in remittance determination. Countries which export a larger share of high-skilled (educated) migrants receive less per capita remittances than countries which export a larger proportion of low-skilled migrants. It also finds that the level of poverty in a labor-sending country does not have a positive impact on the level of remittances received.
Non-Crossing Tableaux

In combinatorics there is a well-known duality between non-nesting and non-crossing objects. In algebra there are many objects which are standard, for example, standard Young tableaux, standard monomials, and standard bitableaux. We adopt a point of view that these standard objects are really non-nesting, and we find their non-crossing counterparts.
Gluino decays with heavier scalar superpartners

We compute gluino decay widths in supersymmetric theories with arbitrary flavor and CP violation angles. Our emphasis is on theories with scalar superpartner masses heavier than the gluino such that tree-level two-body decays are not allowed, which is relevant, for example, in split supersymmetry. We compute gluino decay branching fractions in several specific examples and show that it is plausible that the only accessible signal of supersymmetry at the LHC could be four top quarks plus missing energy. We show another example where the only accessible signal for supersymmetry is two gluon jets plus missing energy.