cssi/SciSciGPT-SciSciNet huggingface dataset:
Investigation and its discontents: Some constraints on progress in psychological research

Abstract This article examines a number of prominent trends in the conduct of psychological research and considers how they may limit progress in our field. Failure to appreciate important differences in temperament among researchers, as well as differences in the particular talents researchers bring to their work, has prevented the development in psychology of a vigorous tradition of fruitful theoretical inquiry. Misplaced emphasis on quantitative “productivity,” a problem for all disciplines, is shown to have particularly unfortunate results in psychology. Problems associated with the distorting effects of seeking grant support are shown to interact with the first two difficulties. Finally, the distorting effects of certain kinds of experimental studies are discussed, together with their implications for progress in this field.
Optimization of Flatback Airfoils for Wind Turbine Blades Using a Multi-Objective Genetic Algorithm

In recent years, the airfoil sections with blunt trailing edge (called flatback airfoils) have been proposed for the inboard regions of large wind-turbine blades because they provide several structural and aerodynamic performance advantages. In a previous paper, ASME ES2010-90373, we employed a single objective genetic algorithm (GA) for shape optimization of flatback airfoils for generating maximum lift to drag ratio. The computational efficiency of GA was significantly enhanced with an artificial neural network (ANN). The commercially available software FLUENT was employed for calculation of the flow field using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a turbulence model. In this paper, we employ a multi-objective GA to optimize the flatback airfoils to achieve two objectives, namely the generation of maximum lift as well as the maximum lift to drag ratio. It is shown that the multi-objective GA optimization can generate superior flatback airfoils compared to those obtained by using single objective GA algorithm.Copyright © 2012 by ASME
Examples of Fano varieties of index one that are not birationally rigid

A conjecture of Pukhlikov states that a smooth Fano variety of dimension at least 4 and index one is birationally rigid. We show that a general member of the linear system given by the ample generator of the Picard group of the moduli space of stable, rank 2 bundles with fixed determinant of odd degree on a curve of genus at least 3 is not birationally rigid.
The depsipeptide method for solid-phase synthesis of difficult peptides.

After about one century of peptide chemistry, the main limitation to the accessibility of peptides and proteins via chemosynthesis is the arising of folding and aggregation phenomena. This is true not only for sequences above a critical length but also for several biologically relevant substrates that are relatively short yet form either highly folded structures (e.g. WW domains) or fibrils and aggregates after final deprotection (β-amyloid peptide). Such so-called difficult sequences may be more easily obtained via their corresponding depsipeptides (O-acyl isopeptides), ester isomers that are often easier to assemble and purify, and are smoothly converted to the parent amides under mild conditions. The depsipeptide method is the most recent technique to improve the outcome of difficult syntheses, applicable to sequences containing residues of serine or threonine. A brief overview is presented about chemical aspects of the method, the steps that have been undertaken for its optimization, and the evaluation of its efficiency. Further applications of analogous principles to other critical topics in peptide synthesis such as condensation of peptide segments and solid-phase synthesis of naturally occurring cyclodepsipeptides are addressed as well. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Obstructions to nonnegative curvature and rational homotopy theory

We establish a link between rational homotopy theory and the problem which vector bundles admit a complete Riemannian metric of nonnegative sectional curvature. As an application, we show for a large class of simply-connected nonnegatively curved manifolds that, if C lies in the class and T is a torus of positive dimension, then "most" vector bundles over C x T admit no complete nonnegatively curved metrics.
Total chemical synthesis of proteins

This tutorial review outlines the modern ligation methods that enable the efficient total chemical synthesis of enzymes and other protein molecules. Key to this success is the chemoselective reaction of unprotected synthetic peptides (‘chemical ligation’). Notably, native chemical ligation enables the reaction of two unprotected peptides in aqueous solution at neutral pH to form a single product in near quantitative yield. Full-length synthetic polypeptides are folded to form the defined tertiary structure of the target protein molecule, which is characterized by mass spectrometry, NMR, and X-ray crystallography, in addition to biochemical and/or biological activity.
Selective Fertilization in Pollen Mixtures.

Equality in fertilizing power of gametes dissimilar in the hereditary factors they carry is a corollary of Mendelism. It has been thought that certain exceptions to this general rule may exist. Differential fecundating ability has been suggested from time to time as a possible interpretation of otherwise un accountable results. The earlier uses of this hypothesis of inequality in sperm efficiency, such as Castle's (1903) theory of sex determination, Cuenot's (1908) conception of the reason for the non-appearance of homozygous yellow mice, have since been found to be unnecessary. The interpretation of linkage phe nomena according to the reduplication hypothesis, while essen tially different in application, holds somewhat the same implica tion as selective fertilization, that is, differential operative power of cells of unlike germinal construction. As the yellow mouse problem was finally resolved to a selective elimination of zygotes so many puzzles have had considerable light thrown on them by a more complete understanding of the factor relations. Many instances of the non-appearance of cer tain types are known to be the result of the action of lethal factors. Good illustrations of this are found in Drosophila (Muller, 1918). Other cases of elimination immediately after fertilization or early in development are known in maize. Sometimes abortion of a part of the gametes before fertilization takes place and it is assumed that the elimination is selective. Belling (1914) has shown that in Stizolobium 50 per cent. of the pollen grains and ovules regularly abort in certain types. The aberrant results from the @Enotheras are now generally considered largely, if not wholly, to be due to differential destruction of both
A case of trichosporon beigelii endocarditis 8 years after aortic valve replacement

We report a case of Trichosporon beigelii endocarditis in a 77-year-old diabetic man who presented with an embolic stroke 8 years ago after a porcine aortic valve replacement. He was treated successfully with amphotericin, rifampin, and replacement of the original porcine valve; however, he died suddenly 8 months later from unknown causes. Blood cultures 2 months prior to death were negative. The first manifestation of the endocarditis was a left hemiparesis followed some days later by a splenic infarction. Transthoracic echocardiography failed to demonstrate the aortic vegetation, which was clearly visualized subsequently by transesophageal echocardiography. The literature on Trichosporon beigelii endocarditis is reviewed.
Functionalized Cyclopropenes and Methylenecyclopropenes from Dianions of 3-Hydroxymethylcyclopropenes.

1,2-Disubstituted 3-hydroxymethylcyclopropene derivatives have been synthesized by reacting the dianions of 1-alkyl-3-hydroxymethylcyclopropenes with a range of electrophiles. Additionally, a complementary procedure is described for one-pot sequential alkylation/rearrangement to provide a convenient synthesis of a chiral methylenecyclopropane directly from a 1-alkyl-3-hydroxymethylcyclopropene.
An architecture-centric software maintainability assessment using information theory

Architecture-based metrics can provide valuable information on whether or not one can localize the effects of modification (such as adjusting data flows or control flows) in software and can therefore be used to prevent the changes from adversely affecting other software components. This paper proposes an architecture-centric metric using entropy for assessing structural dependencies among software components. The proposed metric is based on a mathematical model representing the maintainability snapshot of a system. The introduced architectural-level metric includes measures for coupling and cohesion. From this model, the relative maintainability of a component, referred to as a maintainability profile, can be developed to identify architectural decisions that are detrimental to the maintainability of a system. Copyright © 2008 John Wiley & Sons, Ltd.
Resonant Excitation of Disk Oscillations in Deformed Disks II: A Model of High-Frequency QPOs

The amplification of disk oscillations resulting from nonlinear resonant couplings between the oscillations and a disk deformation is examined. The disk is geometrically thin and general relativistic with a non-rotating central source. A Lagrangian formulation is adopted. The author examined the same problem a few years ago, but here we derive a general stability criterion in a more perspective way. Another distinct point from the previous work is that in addition to the case where the deformation is a warp, the case where the deformation is a one-armed pattern symmetric with respect to the equatorial plane is considered. The results obtained show that in addition to the previous results that the inertial-acoustic mode and g-mode oscillations are amplified by horizontal resonance in warped disks, they also amplified by horizontal resonance in disks deformed by one-armed pattern symmetric with respect to the equatorial plane. If we consider local oscillations that are localized around boundaries of their propagation region, the resonance occurs at 4rg, where rg is the Schwarzschild radius. If nonlocal oscillations are considered, frequency ranges of oscillations where oscillations are resonantly amplified are specified.
Inclusion of tobacco exposure as a predictive factor for decreased bone mineral content.

Tobacco exposure has been implicated as a risk factor for decreased bone density, which might result in osteoporosis. Cotinine, a metabolite of nicotine, is commonly used as a marker for tobacco exposure (active or passive). The objective of the present study was to compare tobacco exposure with other predictive factors for low bone mineral content (BMC), as determined by dual photon bone absorptiometry (DXA) in a national U.S. sample. Publicly available interview and clinical examination data from the Third National Health and Nutrition Examination Survey, 1988-1994 (NHANES-III) were used. Our data included 14,060 subjects from 19,528 randomly selected representative U.S. households. Clinical laboratory data included serum values for calcium and cotinine. BMC was assessed radiologically by DXA at five proximal femur sites. BMC values were adjusted for age, as well as height, weight, and bone area to correct for bone and body size. We used t tests to compare continuous variables and chi-square tests to explore associations between categorical variables. Multivariate regression models were developed for each gender with appropriate covariates. Intertrochanter BMC explained the most variation (highest R 2 ) and was selected as the basis of the comparison. Serum cotinine had a significant inverse relationship to BMC in both males (p = .0069) and females (p = .0063). Serum cotinine, as a marker for tobacco exposure, is a statistically significant risk factor for decreased BMC in both genders and should be included in multivariate regression models to predict low BMC.
The efficient evaluation of the hypergeometric function of a matrix argument

We present new algorithms that efficiently approximate the hypergeometric function of a matrix argument through its expansion as a series of Jack functions. Our algorithms exploit the combinatorial properties of the Jack function, and have complexity that is only linear in the size of the matrix.
Endogenous Agenda Formation in Three-Person Committees

This paper analyzes a 3-person voting game in which two or three players have the ability to choose alternatives to be considered. Once the set of possible alternatives and the structure of the voting procedure are known, the players can solve for the outcome. Thus, the actual choice over outcomes takes place in the choice of alternatives to be voted on, i.e., the agenda. An equilibrium to this agenda-formation game in shown to exist under different assumptions about the information relative to the order of the players in the voting game. Further, this equilibrium is computed and found to possess certain features which are attractive from a normative point of view.
Flag f-vectors of colored complexes

It is shown that restrictions on color-selected subcomplexes stronger than color-shifting cannot be placed on the class of colored complexes without changing the characterization of the flag f-vectors. In particular, it is not possible to make further progress toward a numerical characterization of the flag f-vectors of color-shifted complexes through stronger restrictions on the color-selected subcomplexes.
N-Acylbenzotriazoles: neutral acylating reagents for the preparation of primary, secondary, and tertiary amides

Readily available N-acylbenzotriazoles 2a−q efficiently acylate aqueous ammonia and primary and secondary amines to give primary, secondary, and tertiary amides in good to excellent yields. The wide applicability of the procedure is illustrated by the preparation of (i) α-hydroxyamides from α-hydroxy acids and of (ii) perfluoroalkylated amides.
Time- and VLSI-optimal convex hull computation on meshes with multiple broadcasting

Abstract Our main contribution is to present the first known general-case, time- and VLSI-optimal, algorithm for convex hull computation on meshes with multiple broadcasting. Specifically, we show that for every choice of a positive constant e, the convex hull of a set of an arbitrary set of m (n 1 2 + e ⩽ m ⩽ n) points in the plane input in the first ⌉ m √n ⌈ columns of a mesh with multiple broadcasting of size √n × √n can be computed in Θ ( m √n ) time.
Orthogonal Polynomials of Types A and B and Related Calogero Models

There are examples of Calogero–Sutherland models associated to the Weyl groups of type A and B. When exchange terms are added to the Hamiltonians the systems have non-symmetric eigenfunctions, which can be expressed as products of the ground state with members of a family of orthogonal polynomials. These polynomials can be defined and studied by using the differential-difference operators introduced by the author in Trans. Am. Math. Soc. 311, 167–183 (1989). After a description of known results, particularly from the works of Baker and Forrester, and Sahi; there is a study of polynomials which are invariant or alternating for parabolic subgroups of the symmetric group. The detailed analysis depends on using two bases of polynomials, one of which transforms monomially under group actions and the other one is orthogonal. There are formulas for norms and point-evaluations which are simplifications of those of Sahi. For any parabolic subgroup of the symmetric group there is a skew operator on polynomials which leads to evaluation at (1,1,… ,1) of the quotient of the unique skew polynomial in a given irreducible subspace by the minimum alternating polynomial, analogously to a Weyl character formula. The last section concerns orthogonal polynomials for the type B Weyl group with an emphasis on the Hermite-type polynomials. These can be expressed by using the generalized binomial coefficients. A complete basis of eigenfunctions of Yamamoto's BN spin Calogero model is obtained by multiplying these polynomials by the ground state.
Linguistic convergence: Indo-Aryanization of Dravidian languages

Abstract It is well known that over three millennia of language contact on the Indian sub-continent has resulted in the convergence of linguistic features of the four language families of the area. A major part of this ongoing process is the adaptation of Indo-Aryan characteristics by the twenty-three or so Dravidian languages. The present paper is an attempt to study the various aspects of this phenomenon in broad outline. Following the introduction, the language contact situation between Sanskrit, Prakrit, and the modern Indo-Aryan languages on the one hand, and the literary and non-literary Dravidian languages on the other, is described. Next, variation in the nature and extent of Indo-Aryanization both within and across the Dravidian languages is outlined. Section 4 deals with the impact of Indo-Aryan on Dravidian phonology, morphology, lexicon and syntax; this is followed by a discussion of the processes of nativization of borrowed elements. Section 6 describes the sociolinguistic implications of Indo-Aryanization, especially the emergence of the manipravala style, the reinforcement of caste dialects and diglossia, and language attitudes. The conclusion raises some issues concerning the role of Indo-Aryanization in the evolution of Dravidian languages.
PARSEC-SCALE BLAZAR MONITORING: PROPER MOTIONS

We present proper motions obtained from a dual-frequency, six-epoch, VLBA polarization experiment monitoring a sample of 12 blazars. The observations were made at 15 and 22 GHz at bimonthly intervals over 1996. A total of 10 of the 11 sources for which proper motion could be reliably determined are superluminal. Only J2005+77 has no superluminal components. Three sources (OJ 287, J1224+21, and J1512-09) show motion faster than 10h-1c, requiring γpattern of at least 10h-1 (H0 = 100h km s-1 Mpc-1). We compare our results to those in the literature and find motions outside the previously observed range for four sources. While some jet components exhibit significant nonradial motion, most motion is radial. In at least two sources there are components moving radially at significantly different structural position angles. In five of six sources (3C 120, J1224+21, 3C 273, 3C 279, J1512-09, and J1927+73) that have multiple components with measurable proper motion, the innermost component is significantly slower than the others, suggesting that acceleration occurs in the jet. In the motions of individual components we observe at least one decelerating motion and two "bending" accelerations that tend to align their motions with larger scale structure. We also discuss in detail our procedures for obtaining robust kinematical results from multifrequency VLBI data spanning several epochs.
Feasibility Study of the In-Situ Combustion Process Using TGA/DSC Techniques

The influence of reservoir rock on the in-situ combustion process has been recognized by many investigators as an important part of the process. Several experimental studies have shown the effects of reservoir rock on the in-situ combustion process. However, all the available screening criteria neglect this important and decisive criterion. This paper describes how the reservoir rock affects the minimum oil content necessary for the self-sustained combustion, which is introduced as a new criterion for the selection of suitable reservoirs for the process. Differential Scanning Calorimetry (DSC) was employed to determine the heat value of the oil in the presence of the reservoir rock. The minimum temperature required for the total consumption of the fuel was obtained by the use of Thermogravimetric Analysis (TGA) and DSC. The minimum amount of oil necessary to sustain the combustion was calculated from these two parameters and compared with the oil saturation of the reservoir. Reservoirs with oil saturations above this minimum value were considered feasible. In-situ combustion tube experiments performed on actual reservoir rocks obtained from Kansas fields confirmed the validity of the prediction.
Does Securitization Support Entrepreneurial Activity

In this paper, we investigate the impact of loan securitization on entrepreneurial activity in the United States. We first provide evidence that securitization alters the lending strategy for small business by both small and large banks. In particular, we find a positive relation between the banks’ overall credit supply to small businesses and the degree of securitization of their loan assets. We also find three potential channels through which banks’ loan securitization contributes to the development of entrepreneurship. First, direct securitization of small business loans is positively related to increases in entrepreneurial activity. Second, the increased lending supply induced by securitization of non-small business loans also positively relates to business formation. Third, entrepreneurs appear to benefit from an increased ability to borrow from their real-estate holdings facilitated by mortgage loan securitization. Furthermore, we note that this positive influence is only evident during times of positive economic growth and that the relation was not significant in the 2007 to 2009 economic downturn.
Association Rules for Recommendations with Multiple Items

In Web-based environments, a site has the ability to recommend multiple items to a customer in each interaction. Traditionally, rules used to make recommendations either have single items in their consequents or have conjunctions of items in their consequents. Such rules may be of limited use when the site wishes to maximize the likelihood of the customer being interested in at least one of the items recommended in each interaction (with a session comprising multiple interactions). Rules with disjunctions of items in their consequents and conjunctions of items in their antecedents are more appropriate for such environments. We refer to such rules as disjunctive consequent rules. We have developed a novel mining algorithm to obtain such rules. We identify several properties of disjunctive consequent rules that can be used to prune the search space when mining such rules. We demonstrate that the pruning techniques drastically reduce the proportion of disjunctive rules explored, with the pruning effectivenes...
Exponential Tails in the Centroid Velocity Distributions of Star-forming Regions

Probability density functions (pdfs) of 13CO emission line centroid (line-of-sight, intensity-weighted average) velocities are presented for several densely sampled molecular clouds as quantitative descriptors of their underlying dynamics. Some are found to be approximately Gaussian in form, but most of the pdfs exhibit relatively broader, often nearly exponential, tails, similar to the behavior found for pdfs of velocity differences and derivatives (but not the velocity field itself) in experiments and numerical simulations of incompressible turbulence. Other nonturbulent processes can also give rise to non-Gaussian pdfs, although we know of no interpretations (turbulent or otherwise) that can unambiguously account for the nearly exponential tails. The centroid pdfs presented here are less sensitive to systematic motions, optical depth effects, and secondary thermal components than are individual molecular line profiles, which have also been used as pdf estimators and which have also been recently found to exhibit excess wing emission similar to the broad pdf tails found here.
Stein's method, Jack measure, and the Metropolis algorithm

The one parameter family of Jackα measures on partitions is an important discrete analog of Dyson's β ensembles of random matrix theory. Except for special values of α = ½, 1, 2 which have group theoretic interpretations, the Jackα measure has been difficult if not intractable to analyze. This paper proves a central limit theorem (with an error term) for Jackα measure which works for arbitrary values of α. For α = 1 we recover a known central limit theorem on the distribution of character ratios of random representations of the symmetric group on transpositions. The case α = 2 gives a new central limit theorem for random spherical functions of a Gelfand pair (or equivalently for the spectrum of a natural random walk on perfect matchings in the complete graph). The proof uses Stein's method and has interesting combinatorial ingredients: an intruiging construction of an exchangeable pair, properties of Jack polynomials, and work of Hanlon relating Jack polynomials to the Metropolis algorithm.
A New Magnetically Ordered Polymorph of CuMoO4: Synthesis and Characterization of ε-CuMoO4

A new polymorph of CuMoO4, e-CuMoO4, has been synthesized and characterized. The material exhibits a three-dimensional structure with tetramers of edge-shared Cu2+O5 square pyramids that link to the Mo6+O4 tetrahedra. Magnetic susceptibility measurements indicate that the material orders magnetically, with a ferromagnetic component below 10 K.
Knowledge spillovers in biotechnology: sources and incentives

This paper sheds light on the questions, Why does knowledge spill over? and How does knowledge spill over? The answer to these questions we suggest lies in the incentives confronting scientists to appropriate the expected value of their knowledge considered in the context of their pathdependent career trajectories. In particular, we focus on the ability of scientists to appropriate the value of knowledge embedded in their human capital along with the incentive structure influencing if and how scientists choose to commercialize their knowledge. We conclude that the spillover of knowledge from the source creating it, such as a university, research institute, or industrial corporation, to a new-firm startup facilitates the appropriation of knowledge for the individual scientist(s) but not necessarily for the organization creating that new knowledge in the first place.
Ionic interactions of divalent metals in natural waters

Abstract The interactions of the ionic components of natural waters have been examined using the ion pairing and specific interaction models. The present paper reviews the recent developments made in using these models to estimate the activity and speciation of divalent metals in natural waters as a function of ionic strength. Since the ion pairing studies of most trace metals have been made in NaClO4, the activity coefficients of cations and anions have been determined in this media. The activity coefficients for free or uncomplexed ions have been estimated from the equation In λ i = Z i 2 ƒ + B i 0 I + B i 1 ƒ 1 + C i I 2 where f and f1 are functions of ionic strength; Zi is the charge on ion i; Bi0, Bi1 and Ci are ionic Pitzer parameters derived from the values for Na+ and ClO4− salts using the mean salt approximation (γK = γCl). The Pitzer coefficients were determined for a number of cations and anions. By combining the estimated activity coefficients for metals and anions with measured stability constants at a given ionic strength, it was possible to estimate the activity coefficient of various ion pairs and extrapolate the stability constants to infinite dilution. The results showed that ion pairs of the same charge type had similar values at a given ionic strength. This allowed us to estimate the effect of ionic strength on the stability constants for a number of divalent metals (Mg2+, Ca2+, Sr2+, Ba2+, Mn2+, Fe2+, Co2+, Pb2+, Ni2+, Zn2+) with a number of inorganic ligands (Cl−, OH−, HCO3−, CO32−, SO42−). The equations representing the ionic strength dependence of the stability constants are of the form In K MX = In K MX + Z MX 2 ƒ + B MX 0 I+ B MX 1 ƒ 1 + C MX I 2 where the values of ZMX, BMX0, BMX1, and CMX are obtained from the Pitzer parameters for the free ions and the ion pairs (MX). These equations can be used to determine the speciation of divalent metal in natural waters over a wide range of ionic strength. Results of speciation calculations at seawater ionic strength show the same patterns as recorded in the literature, with some differences in the proportions of some metal ion pairs. The limitations of using this approach to account for the ionic interactions of metals and needed improvements to the model are discussed.
A methodology for minimizing maintenance costs

Research conducted in the case study of a large applications system shows that the two primary causes of high maintenance costs are1. The frequency of user-requested changes to software2. The psychological complexity of the softwareA "tool kit" is suggested that, when applied to the design of new systems or rewrites, will1. Produce systems that users are less likely to need changed2. Contribute to the reduction of psychological complexity of code, making it easier to change when necessaryThe tool kit is easy to use, can be applied to large or small systems in any language on any equipment, and requires no purchase of hardware or software.
Pulse propagation near exciton resonance: Anomalous transition between slow and fast light

Experimental studies of optical pulse propagation near exciton absorption resonance in an optically thick GaAs quantum well reveal an anomalous transition between regimes of slow and fast light.
The Barbier-Grignard-type carbonyl alkylation using unactivated alkyl halides in water.

The aqueous Barbier−Grignard-type alkylation of aldehydes with unactivated alkyl iodides and bromides was developed. By using a combination of zinc and cuprous iodide, catalyzed by indium(I) chloride, we successfully added tertiary, secondary, and primary alkyl halides to various aromatic aldehydes in 0.07 M aqueous Na2C2O4. A mechanistic rationale for the success of the reaction has been proposed.
Chiral random matrix model for critical statistics

Abstract We propose a random matrix model that interpolates between the chiral random matrix ensembles and the chiral Poisson ensemble. By mapping this model on a non-interacting Fermi-gas we show that for energy differences less than a critical energy E c the spectral correlations are given by chiral Random Matrix theory whereas for energy differences larger than E c the number variance shows a linear dependence on the energy difference with a slope that depends on the parameters of the model. If the parameters are scaled such that the slope remains fixed in the thermodynamic limit, this model provides a description of QCD Dirac spectra in the universality class of critical statistics. In this way a good description of QCD Dirac spectra for gauge field configurations given by a liquid of instantons is obtained.
Cross sections for short pulse single and double ionization of helium

In a previous publication, procedures were proposed for unambiguously extracting amplitudes for single and double ionization from a time-dependent wavepacket by effectively propagating for an infinite time following a radiation pulse. Here we demonstrate the accuracy and utility of those methods for describing two-photon single and one-photon double ionization of helium. In particular it is shown how narrow features corresponding to autoionizing states are easily resolved with these methods.
Debris Disks around Sun-like Stars

We have observed nearly 200 FGK stars at 24 and 70 ?m with the Spitzer Space Telescope. We identify excess infrared emission, including a number of cases where the observed flux is more than 10 times brighter than the predicted photospheric flux, and interpret these signatures as evidence of debris disks in those systems. We combine this sample of FGK stars with similar published results to produce a sample of more than 350 main sequence AFGKM stars. The incidence of debris disks is -->4.2+ 2.0?1.1% at 24 ?m for a sample of 213 Sun-like (FG) stars and -->16.4+ 2.8?2.9% at 70 ?m for 225 Sun-like (FG) stars. We find that the excess rates for A, F, G, and K stars are statistically indistinguishable, but with a suggestion of decreasing excess rate toward the later spectral types; this may be an age effect. The lack of strong trend among FGK stars of comparable ages is surprising, given the factor of 50 change in stellar luminosity across this spectral range. We also find that the incidence of debris disks declines very slowly beyond ages of 1 billion years.
Qualitative analysis of neural networks

Results from the qualitative theory of large-scale interconnected dynamical systems are surveyed and utilized to develop a qualitative theory for the Hopfield model of neural networks. Such networks are viewed as an interconnection of many single neurons. The results are phrased in terms of the qualitative properties of the individual neurons and in terms of the properties of the interconnecting structure of the neural networks. This method of analysis makes it frequently possible to circumvent difficulties usually encountered in the analysis of complex systems with high dimension. Aspects of neural networks which are addressed include asymptotic stability, exponential stability, and instability of an equilibrium; estimates of trajectory bounds; estimates of the domain of attraction of an asymptotically stable equilibrium: and stability of neural networks under structural perturbations (arising, e.g. during adaptive learning schemes). The results are not overly conservative. Furthermore, they are in a form which will make them highly useful as constraints in synthesis or design procedures. >
Security in distributed storage systems by communicating a logarithmic number of bits

We investigate the problem of maintaining an encoded distributed storage system when some nodes contain adversarial errors. Using the error-correction capabilities that are built into the existing redundancy of the system, we propose a simple linear hashing scheme to detect errors in the storage nodes. Our main result is that for storing a data object of total size M using an (n, k) MDS code over a finite field Fq, up to t1 = ⌊(n − k)/2⌋ errors can be detected, with probability of failure smaller than 1/M, by communicating only O(n(n−k) logM) bits to a trusted verifier. Our result constructs small projections of the data that preserve the errors with high probability and builds on a pseudorandom generator that fools linear functions. The transmission rate achieved by our scheme is asymptotically equal to the min-cut capacity between the source and any receiver.
Simple high-quality lossy image coding scheme

A simple yet efficient image data compression method is presented. This method is based on coding only those segments of the image that are perceptually significant to the reconstruction of the image. Sequences of image pixels whose gray-level differences from the pixels of the previous row exceed two prespecified thresholds are considered significant. These pixels are coded using a differential pulse code modulation scheme that uses a 15-level recursively indexed nonuniform quantizer for the first pixel in a segment and a 7-level recursively indexed nonuniform quantizer for all other pixels in the segment. The quantizer outputs are Huffman coded. Simulation results show that this scheme can obtain subjectively satisfactory reconstructed images at low bit rates. It is also computationally very simple, which makes it amenable to fast implementation.
Medications for Weight Reduction

Only two drugs are currently approved for long-term use in the treatment of obesity, and four others for short-term use. Evaluating the risk-benefit profile is an essential first step. For individuals who have a low body mass index for whom the risk is small, the risk profile must make the drug acceptable for almost everyone. For higher-risk patients, such as those planning intestinal bypass or who have sleep apnea, a wider range of drugs may be considered. Obesity is a chronic disease that has many causes. Treatment is aimed at palliation—that is, producing and maintaining weight loss. Regardless of the primary site of action, the net effect must be a reduction in food intake or increase in energy expenditure.
Reopening of previously closed macular holes after cataract extraction.

Purpose To evaluate the frequency of reopening of macular holes after cataract extraction. Design Retrospective, comparative, consecutive case series. Methods Two hundred and eleven eyes with idiopathic macular holes closed by vitrectomy were divided into four groups: Group 1: prior cataract extraction; Group 2: vitrectomy then cataract extraction; Group 3: vitrectomy only; and Group 4: vitrectomy and cataract extraction as a combined procedure. The main outcome measure of macular hole reopening was evaluated in relationship to multiple variables. Results Two hundred and eleven eyes were included: Group 1: 56 eyes; Group 2: 86 eyes; Group 3: 41 eyes; and Group 4: 28 eyes. Twenty-four macular holes reopened (11%) (mean follow-up 26.6 months, range, three to 118 months). The greatest number of macular hole reopenings, 17 (20%), were in Group 2. Cox multivariate analysis failed to demonstrate an association between duration of hole, serum use, internal limiting membrane peeling, or stage and reopening of a macular hole. Cox analysis showed a four-fold increased risk of reopening in Group 2 eyes (95% confidence interval [CI]: 1.7 to 11.2; P = .002). Eyes with cystoid macular edema after cataract extraction had a seven-fold increased risk of macular hole reopening (7.72; 95% CI: 2.79 to 21.3; P Conclusions Cataract extraction after successful vitrectomy for macular hole, when complicated by cystoid macular edema (CME), may increase the risk of macular hole reopening.
Strong WW scattering at photon linear colliders

Abstract We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process γγ → ZZ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the Z bosons to enhance the signal relative to the background of transversely polarized ZZ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic f 2 (1270) meson.
Tolcapone suppresses ethanol intake in alcohol-preferring rats performing a novel cued access protocol.

Background Dopamine (DA) has been shown to play a central role in regulating motivated behavior and encoding reward. Chronic drug abuse elicits a state of hypodopaminergia in the mesocorticolimbic (MCL) system in both humans and preclinical rodent models of addiction, including those modeling alcohol use disorders (AUD). Methods Working under the hypothesis that reductions in the bioavailability of DA play an integral role in the expression of the excessive drinking phenotype, the catechol-O-methyltransferase (COMT) inhibitor tolcapone was used as a means to amplify cortical DA concentration and drinking behaviors were then assessed. Sucrose and ethanol (EtOH) consumption were measured in P and Wistar rats in both a free choice drinking protocol and a novel cued access protocol. Results Tolcapone attenuated the consumption of EtOH, and to a lesser extent sucrose, in P rats in the cued access protocol, while no effect was observed in the free choice drinking protocol. Tolcapone also decreased EtOH consumption in high drinking Wistar rats. A follow-up experiment using the indirect DA agonist d-amphetamine showed no change in EtOH consumption. Conclusions Collectively, these data suggest that COMT inhibitors may be capable of alleviating the extremely motivating or salient nature of stimuli associated with alcohol. The hypothesis is put forth that the relative specificity of tolcapone for cortical DA systems may mediate the suppression of the high seeking/drinking phenotype.
Energy and length in a topological planar quadrilateral

We provide bounds for the product of the lengths of distinguished shortest paths in a finite network induced by a triangulation of a topological planar quadrilateral.
Mechanisms of lubrication and wear of a bonded solid-lubricant film

To obtain a better understanding of how bonded solid-lubricant film lubricate and wear (in general), the tribological properties of polyimide-bonded graphite fluoride films were studied (in specific). A pin-on-disk type of testing apparatus was used; but in addition to sliding a hemispherically tipped rider, a rider with a 0.95-mm-diameter flat area was slid against the film. This was done so that a lower, less variable contact stress could be achieved. Two stages (regimes) of lubrication were found to occur. In the first, the film supported the load and the lubricating mechanism consisted of the shear of a thin surface layer (of the film) between the rider and the bulk of the film. The second occurred after the bonded film had worn to the substrate, and consisted of the shear of very thin lubricant film between the rider and flat plateaus generated on the metallic substrate asperities. The film wear mechanism was found to be strongly dependent on contact stress. Presented at the 35th Annual Meeting in An...
Minimum-Fuel Control of Second-Order Systems with Real Poles

The controlled system has the transfer function G(s)=K/(s-? 1 )(s-? 2 ). The control input is u(t), |u(t)|?1, and the out put is y 1 (t). the control which forces any initial state y 1 (0), ? 1 (0) to the terminal state y 1 (T), ? 1 ,(T), such that -K/? 1 ? 2 ?y 1 (T)?K/? 1 ? 2 , ? 1 (T)=0, and which minimizes the fuel, F(T)=? 0 T |u(t)|dt is determined. The phase plane is divided into three sets G - , G + , and G 0 ; if the state is in G - then u(t)=?1 is used; if the state is in G + , then u(t)=+1 is used; if the state is in G 0 , then u(t)=0 is used.
HOBBY-EBERLY TELESCOPE OBSERVATIONS OF THE DARK HALO IN NGC 821*

We present stellar line-of-sight velocity distributions (LOSVDs) of elliptical galaxy NGC 821 obtained to approximately 100'' (over two effective radii) with long-slit spectroscopy from the Hobby-Eberly Telescope. Our measured stellar LOSVDs are larger than the planetary nebulae measurements at similar radii. We fit axisymmetric orbit-superposition models with a range of dark halo density profiles, including two-dimensional kinematics at smaller radii from SAURON data. Within our assumptions, the best-fitted model gives a total enclosed mass of 2.0 x 10{sup 11} M {sub sun} within 100'', with an accuracy of 2%; this mass is equally divided between halo and stars. At 1 R{sub e} , the best-fitted dark matter halo accounts for 13% of the total mass in the galaxy. This dark halo is inconsistent with previous claims of little to no dark matter halo in this galaxy from planetary nebula measurements. We find that a power-law dark halo with a slope 0.1 is the best-fitted model; both the no dark halo and Navarro-Frenk-White models are worse fits at a greater than 99% confidence level. NGC 821 does not appear to have the expected dark halo density profile. The internal moments of the stellar velocity distribution show that the model with nomore » dark halo is radially anisotropic at small radii and tangentially isotropic at large radii, while the best-fitted halo models are slightly radially anisotropic at all radii. We test the potential effects of model smoothing and find that there are no effects on our results within the errors. Finally, we run models using the planetary nebula kinematics and assuming our best-fitted halos and find that the planetary nebulae require radial orbits throughout the galaxy.« less
Corporate social responsibility and economic performance

We describe some perspectives on corporate social responsibility (CSR), in order to provide a context for considering the strategic motivations and implications of CSR. Based on this framework, which is based on characterizing optimal firm decision-making and underlies most existing work on CSR, we propose an agenda for further theoretical and empirical research on CSR. We then summarize and relate the articles in this special issue to the proposed agenda.
Contactless measurement of recombination lifetime in photovoltaic materials

Abstract Contactless measurement of important semiconductor parameters has become the goal of current semiconductor diagnostics. Here we will describe an improved version of radio-frequency photoconductive decay operating in the ultra-high frequency (UHF) region. Previous work has referred to the general technique as UHF photoconductive decay. This work will show that the improved technique is capable of measuring samples ranging in size from submicron thin films to large silicon ingots. The UHF frequency region is an ideal compromise for volume penetration and lifetime resolution with system response or 10 ns or less.
Radiative Transfer in a Clumpy Universe. IV. New Synthesis Models of the Cosmic UV/X-Ray Background

We present improved synthesis models of the evolving spectrum of the UV/X-ray diffuse background, updating and extending our previous results. Five new main components are added to our radiative transfer code CUBA: (1) the sawtooth modulation of the background intensity from resonant line absorption in the Lyman series of cosmic hydrogen and helium; (2) the X-ray emission from the obscured and unobscured quasars that gives origin to the X-ray background; (3) a piecewise parameterization of the distribution in redshift and column density of intergalactic absorbers that fits recent measurements of the mean free path of 1 ryd photons; (4) an accurate treatment of the photoionization structure of absorbers, which enters in the calculation of the helium continuum opacity and recombination emissivity; and (5) the UV emission from star-forming galaxies at all redshifts. We provide tables of the predicted H I and He II photoionization and photoheating rates for use, e.g., in cosmological hydrodynamics simulations of the Lyα forest and a new metallicity-dependent calibration to the UV luminosity density-star formation rate density relation. A "minimal cosmic reionization model" is also presented in which the galaxy UV emissivity traces recent determinations of the cosmic history of star formation, the luminosity-weighted escape fraction of hydrogen-ionizing radiation increases rapidly with look-back time, the clumping factor of the high-redshift intergalactic medium evolves following the results of hydrodynamic simulations, and Population III stars and miniquasars make a negligible contribution to the metagalactic flux. The model provides a good fit to the hydrogen-ionization rates inferred from flux decrement and proximity effect measurements, predicts that cosmological H II (He III) regions overlap at redshift 6.7 (2.8), and yields an optical depth to Thomson scattering, τes = 0.084 that is in agreement with Wilkinson Microwave Anisotropy Probe results. Our new background intensities and spectra are sensitive to a number of poorly determined input parameters and suffer from various degeneracies. Their predictive power should be constantly tested against new observations. We are therefore making our redshift-dependent UV/X emissivities and CUBA outputs freely available for public use at http://www.ucolick.org/~pmadau/CUBA.
Decompactifications and massless D-branes in hybrid models

A method of determining the mass spectrum of BPS D-branes in any phase limit of a gauged linear sigma model is introduced. A ring associated to monodromy is defined and one considers K-theory to be a module over this ring. A simple but interesting class of hybrid models with Landau-Ginzburg fibres over $ {\mathbb{P}^n} $ are analyzed using special Kahler geometry and D-brane probes. In some cases the hybrid limit is an infinite distance in moduli space and corresponds to a decompactification. In other cases the hybrid limit isat a finite distance and acquires massless D-branes. An example studied appears to correspond to a novel theory of supergravity with an SU(2) gauge symmetry where the gauge and gravitational couplings are necessarily tied to each other.