cssi/SciSciGPT-SciSciNet huggingface dataset:
Collective Reputation and Quality

Firms who sell regional or specialty products often share a collective reputation based on aggregate quality. Collective reputation can be approached as a dynamic common property resource problem. We show that for an experience good without firm traceability, individual firms have the incentive to choose quality levels that are sub-optimal for the group. These results support minimum quality standards. Trigger strategies are analyzed as an alternative solution to this problem. Finally, the implications of these results are discussed as they relate to the case study of Washington apples. Specialty, regional, authentic, and local food products have become a more important part of consumer purchases in recent years. Firms have responded by marketing food products that come from specific geographic areas. This trend in consumers’ preferences has led the European Union to introduce protected designations of origin labels and protected geographical identification labels, which provide protection of food names on a geographical or traditional basis, ranging from Parmesan cheese to such lesser-known items such as Galician veal. In the United States, there are popular state products that carry labels, such as Washington apples, Idaho potatoes,
IPM synchronous machine drive response to a single-phase open circuit fault

This paper investigates the steady-state and dynamic response of an interior permanent magnet (IPM) synchronous machine drive to a single-phase open-circuit fault. This fault results in rotational electromagnetic asymmetry on both the stator and rotor, making it difficult to analyze using classical dq-transformation techniques. This paper presents a new dq synchronous-frame machine model that is capable of handling this highly asymmetrical fault condition, including the effects of q axis magnetic saturation. Fault responses with two alternative post-fault control strategies are investigated: (1) opening all of the inverter switches so that the machine behaves as an uncontrolled generator (UCG), with the two unfaulted phases connected to the inverter DC link via the antiparallel diodes; and (2) shorting the two remaining unfaulted phases together using the inverter switches. Results of this investigation show that the fault response is generally more benign using the UCG control strategy, with significantly lower phase currents and pulsating torque than corresponding values delivered using the phase-shorting strategy.
Accountability and Flexibility in Public Schools: Evidence from Boston's Charters And Pilots

Charter schools are publicly funded but operate outside the regulatory framework and collective bargaining agreements characteristic of traditional public schools. In return for this freedom, charter schools are subject to heightened accountability. This paper estimates the impact of charter school attendance on student achievement using data from Boston, where charter schools enroll a growing share of students. We also evaluate an alternative to the charter model, Boston's pilot schools. These schools have some of the independence of charter schools, but operate within the school district, face little risk of closure, and are covered by many of same collective bargaining provisions as traditional public schools. Estimates using student assignment lotteries show large and significant test score gains for charter lottery winners in middle and high school. In contrast, lottery-based estimates for pilot schools are small and mostly insignificant. The large positive lottery-based estimates for charter schools are similar to estimates constructed using statistical controls in the same sample, but larger than those using statistical controls in a wider sample of schools. The latter are still substantial, however. The estimates for pilot schools are smaller and more variable than those for charters, with some significant negative effects.
Efficient 3D grids for image reconstruction using spherically-symmetric volume elements

Incorporation of spherically-symmetric volume elements (blobs), instead of the conventional voxels, into iterative image reconstruction algorithms, has been found in our previous studies to lead to significant improvement in the quality of the reconstructed images. Furthermore, for three-dimensional (3D) positron emission tomography the 3D algebraic reconstruction technique using blobs can reach comparable or even better quality than the 3D filtered backprojection method after only one cycle through the projection data. The only shortcoming of the blob reconstruction method is an increased computational demand, because of the overlapping nature of the blobs. In our previous studies the blobs were placed on the same 3D simple cubic grid as used for voxel basis functions. For spherically-symmetric basis functions there are more advantageous arrangements of the 3D grid, enabling a more isotropic distribution of the spherical functions in the 3D space and a better packing efficiency of the image spectrum. Our studies confirmed that, when using the body centered cubic grid, the number of grid points can be effectively reduced, decreasing the computational and memory demands while preserving the quality of the reconstructed images. >
High-Order Compact-Difference Schemes for Time-Dependent Maxwell Equations

Two high-order compact-difference schemes have been developed for solving three-dimensional, time-dependent Maxwell equations. Spurious high-frequency oscillatory components of the numerical solution, which are considered to be among the principal sources of time instability, are effectively suppressed by a spatial filter. The present numerical schemes are validated by calculations of three-dimensional transient electromagnetic waves within a waveguide, an oscillating electric dipole, and the radar cross section of perfectly electrical conducting sphere.
Testing for pay and promotion bias in an international organization

Purpose – International organizations pursue multiple objectives in hiring policies including cultural diversity, reducing costs and avoiding discrimination among which there can be sharp trade‐offs. The paper has the purpose of studying how these trade‐offs are resolved in the World Bank's hiring processes.Design/methodology/approach – The paper estimates that half of salary and grade differentials between men and women and staff from high‐ and low‐income countries are attributable to differences in productive characteristics. Alternative explanations for the remainder are explored, including omitted variable bias, quotas and discrimination.Findings – The paper argues that the salary and grade differentials and differences in productive characteristics are not compelling explanations. Discrimination probably exists, though less than would be implied by a cost minimizing hiring policy.Originality/value – Provides a discussion of the World Bank's hiring processes.
Greedy sequential maximal independent set and matching are parallel on average

The greedy sequential algorithm for maximal independent set (MIS) loops over the vertices in an arbitrary order adding a vertex to the resulting set if and only if no previous neighboring vertex has been added. In this loop, as in many sequential loops, each iterate will only depend on a subset of the previous iterates (i.e. knowing that any one of a vertex's previous neighbors is in the MIS, or knowing that it has no previous neighbors, is sufficient to decide its fate one way or the other). This leads to a dependence structure among the iterates. If this structure is shallow then running the iterates in parallel while respecting the dependencies can lead to an efficient parallel implementation mimicking the sequential algorithm.In this paper, we show that for any graph, and for a random ordering of the vertices, the dependence length of the sequential greedy MIS algorithm is polylogarithmic (O(log^2 n) with high probability). Our results extend previous results that show polylogarithmic bounds only for random graphs. We show similar results for greedy maximal matching (MM). For both problems we describe simple linear-work parallel algorithms based on the approach. The algorithms allow for a smooth tradeoff between more parallelism and reduced work, but always return the same result as the sequential greedy algorithms. We present experimental results that demonstrate efficiency and the tradeoff between work and parallelism.
Laws of large numbers for dynamical systems with randomly matched individuals

Biologists and economists have analyzed populations where each individual interacts with randomly selected individuals. The random matching generates a very complicated stochastic system. Consequently biologists and economists have approximated such a system with a deterministic system. The justitication for such an approximation is that the population is assumed to be very large and thus some law of large numbers must hold. This paper gives a characterization of random matching schemes for countably infinite populations. In particular this paper shows that there exists a random matching scheme such that the stochastic system and the deterministic system are the same. Finally, we show that if the process lasts finitely many periods and if the population is large enough then the deterministic model offers a good approximation of the stochastic model. In doing so we make precise what we mean by population, matching process, and evolution of the population.
Polynomiography and applications in art, education, and science

Abstract Polynomiography is the art and science of visualizing approximation of the zeros of complex polynomials. Informally speaking, polynomiography allows one to create colorful images of polynomials. These images can subsequently be re-colored in many ways, using one's own creativity and artistry. Polynomiography has tremendous applications in the visual arts, education, and science. The paper describes some of those applications. Artistically, polynomiography can be used to create quite a diverse set of images reminiscent of the intricate patterning of carpets and elegant fabrics, abstract expressionist and minimalist art, and even images that resemble cartoon characters. Educationally, polynomiography can be used to teach mathematical concepts, theorems, and algorithms, e.g., the algebra and geometry of complex numbers, the notions of convergence and continuity, geometric constructs such as Voronoi regions, and modern notions such as fractals. Scientifically, polynomiography provides not only a tool for viewing polynomials, present in virtually every branch of science, but also a tool to discover new theorems.
Convergence from Discrete- to Continuous-Time Contingent Claims Prices

This article generalizes the Cox, Ross, and Rubinstein (1979) binomial option-pricing model, and establishes a convergence from discrete-time multivariate multinomial models to continuous-time multidimensional diffusion models for contigent claims prices. The key to the approach is to approximate the N-dimensional diffusion price process by a sequence of N-variate, (N+1)-nomial processes. It is shown that contingent claims prices and dynamic replicating portfolio strategies derived from the discrete time models converge to their corresponding continuous-time limits. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
Change in view: Principles of reasoning.

Change in View offers an entirely original approach to the philosophical study of reasoning by identifying principles of reasoning with principles for revising one's beliefs and intentions and not with principles of logic. This crucial observation leads to a number of important and interesting consequences that impinge on psychology and artificial intelligence as well as on various branches of philosophy, from epistemology to ethics and action theory.
Gas-phase fragmentation of oligonucleotide ions

Abstract The advent of ionization methods capable of forming gaseous oligonucleotide ions has made mass spectrometry a viable tool for structural studies of nucleic acids. Structural information regarding the primary sequence of a nucleic acid and the nature of its nucleobases via mass spectrometry has relied primarily on the dissociation behavior of ions formed by one or more of the available ionization methods. This review is focused on studies devoted to the fragmentation of oligonucleotide ions. In particular, it relates dissociation phenomenology observed over a wide range of ion types and dissociation conditions. Furthermore, it also relates the various mechanisms that have been proposed to account for the observed behavior. The review is organized along the lines of ionization method. While there is no fundamental reason to organize the review in this way, much of the discourse in the literature has evolved along these lines. The major ionization methods applied to nucleic acids have been fast atom bombardment, electrospray ionization, and matrix-assisted laser desorption ionization. It is apparent in reviewing the observations made to date that a wide range of reaction phenomenology has been observed for the different ion types and even for the same ions subjected to different activation conditions. It is also apparent that more than one dissociation mechanism can contribute, depending upon ionization conditions, ion polarity and charge state, and ion activation conditions.
Fibrewise rational H-spaces

The Leray–Samelson theorem strengthens these statements when the multiplication for G is homotopy associative. In this case, the isomorphism H .GIQ/S^W is one of Hopf algebras, where ^W has the standard (co)multiplication C W ^W !^W ^W given by C.w/Dw 1C1 w for w2W [17, Theorem 3.8.14]. Further, the homotopy equivalence GQ' Q i K.W2iC1; 2iC1/ above is realized by an H-equivalence, where the product of Eilenberg–Mac Lane spaces comes equipped with the unique homotopyassociative and homotopy-commutative multiplication.
Stereospecific preparation of symmetrical (1Z, 3Z)- and (1E, 3E)-2,3-difluoro-1,4-disubstituted-buta-1,3-dienes from 1-bromo-1-fluoroalkenes

Abstract A straightforward method to prepare symmetrical (1 Z , 3 Z )- and (1 E , 3 E )-2,3-difluoro-1,4-disubstituted-buta-1,3-dienes is described. High E / Z ratio 1-bromo-1-fluoroalkenes, prepared by isomerization from the E / Z ≈ 1:1 isomeric mixtures, reacted with Bu 3 SnSnBu 3 and Pd(PPh 3 ) 4 to afford (1 Z , 3 Z )-2,3-difluoro-1,4-disubstituted-buta-1,3-dienes in good yield. ( Z )-1-Bromo-1-fluoroalkenes, which were prepared by kinetic reduction from 1-bromo-1-fluoroalkenes ( E / Z ≈ 1:1), can undergo similar reaction with Bu 3 SnSnBu 3 and Pd(PPh 3 ) 4 /CuI to prepare (1 E , 3 E )-2,3-difluoro-1,4-disubstituted-buta-1,3-dienes.
Towards an efficient tile matrix inversion of symmetric positive definite matrices on multicore architectures

The algorithms in the current sequential numerical linear algebra libraries (e.g. LAPACK) do not parallelize well on multicore architectures. A new family of algorithms, the tile algorithms, has recently been introduced. Previous research has shown that it is possible to write efficient and scalable tile algorithms for performing a Cholesky factorization, a (pseudo) LU factorization, a QR factorization, and computing the inverse of a symmetric positive definite matrix. In this extended abstract, we revisit the computation of the inverse of a symmetric positive definite matrix. We observe that, using a dynamic task scheduler, it is relatively painless to translate existing LAPACK code to obtain a ready-to-be-executed tile algorithm. However we demonstrate that, for some variants, non trivial compiler techniques (array renaming, loop reversal and pipelining) need then to be applied to further increase the parallelism of the application. We present preliminary experimental results.
An Efficient Implementation of a Phase Unwrapping Kernel on Reconfigurable Hardware

The optical quadrature method of microscopy (OQM) was developed at Northeastern University for the purpose of non-invasively capturing phase data to image the sample being studied. This phase data need to be unwrapped before it can be of use. Phase unwrapping is the process by which an integer multiple of 2? is added to a measured, wrapped phase value in order to generate a continuous function. The algorithm used is the minimum LP norm method which uses a two dimensional discrete cosine transform (2-D DCT) to solve the discrete Poisson equation. This calculation forms the most computationally expensive part of the minimum LP norm method. This paper presents an implementation on reconfigurable hardware that performs the 2-D DCT over the entire image, solves the Poisson equation and then performs the two dimensional inverse discrete cosine transform (2-D IDCT) using a novel FPGA implementation of the DCT with a semi-floating point data representation.
Electromechanical magnetization switching

We show that the magnetization of a torsional oscillator that, in addition to the magnetic moment also possesses an electrical polarization, can be switched by the electric field that ignites mechanical oscillations at the frequency comparable to the frequency of the ferromagnetic resonance. The 180° switching arises from the spin-rotation coupling and is not prohibited by the different symmetry of the magnetic moment and the electric field as in the case of a stationary magnet. Analytical equations describing the system have been derived and investigated numerically. Phase diagrams showing the range of parameters required for the switching have been obtained.
Mesoporous silica nanoparticle based controlled release, drug delivery, and biosensor systems

Recent advancements in controlling the surface properties and particle morphology of the structurally defined mesoporous silica materials with high surface area (>700 m2 g−1) and pore volume (>1 cm3 g−1) have significantly enhanced their biocompatibility. Various methods have been developed for the functionalization of both the internal pore and exterior particle surfaces of these silicates with a tunable pore diameter ranging from 2 to 30 nm and a narrow pore size distribution. Herein, we review the recent research progress on the design of functional mesoporous silica materials for stimuli-responsive controlled release delivery of pharmaceutical drugs, genes, and other chemicals. Furthermore, the recent breakthroughs in utilizing these nanoscale porous materials as sensors for selective detections of various neurotransmitters and biological molecules are summarized.
Tissue disposition of 5-o-carboranyluracil--a novel agent for the boron neutron capture therapy of prostate cancer.

The carboranyl nucleotides β‐d‐5‐o‐carboranyl‐2′‐deoxyuridine (d‐CDU), 1‐(β‐l‐arabinosyl)‐5‐o‐carboranyluracil (d‐ribo‐CU) and the nucleotide base 5‐o‐carboranyluracil (CU), were developed as sensitizers for boron neutron capture therapy (BNCT). A structure activity study was initiated to determine the agent most suitable for targeting prostate tumors. Cellular accumulation studies were performed using LNCaP human prostate tumor cells, and the respective tumor disposition profiles were investigated in male nude mice bearing LNCaP and 9479 human prostate tumor xenografts in their flanks. d‐CDU achieved high cellular concentrations in LNCaP cells and up to 2.5% of the total cellular compound was recovered in the 5′‐monophosphorylated form. In vivo concentrations of d‐CDU were similar in LNCaP and 9479 tumor xenografts. Studies in 9479 xenografted bearing mice indicated that increasing the number of hydroxyl groups in the sugar moeity of the carboranyl nucleosides corresponded with an increased rate and exte...
The Growth and Development of Experimental Research in Political Science

Although political scientists have long expressed skepticism about the prospects for experimental science, an analysis of the first hundred volumes of the American Political Science Review reveals that randomized experiments have grown in impact and prominence. We document how thinking about experimentation has evolved over the century, and demonstrate the growing influence of laboratory, survey, and field experiments. A number of experiments have transformed how political scientists think about causal relationships in specific substantive areas. There are limits to the kinds of questions that experiments can address, but experiments have made important contributions in an array of political science subfields.
Augment-and-Conquer Negative Binomial Processes

By developing data augmentation methods unique to the negative binomial (NB) distribution, we unite seemingly disjoint count and mixture models under the NB process framework. We develop fundamental properties of the models and derive efficient Gibbs sampling inference. We show that the gamma-NB process can be reduced to the hierarchical Dirichlet process with normalization, highlighting its unique theoretical, structural and computational advantages. A variety of NB processes with distinct sharing mechanisms are constructed and applied to topic modeling, with connections to existing algorithms, showing the importance of inferring both the NB dispersion and probability parameters.
Cobaloxime-catalyzed radical alkyl-styryl cross couplings

Abstract Cobaloxime-catalyzed radical alkyl-styryl cross couplings can be accomplished by visible light photolysis of various alkyl bromide + styrene + in-situ-generated CoII (dmgH)2py + Zn in refluxing CH3CN or refluxing 95%EtOH.
Sparse Overlapping Sets Lasso for Multitask Learning and its Application to fMRI Analysis

Multitask learning can be effective when features useful in one task are also useful for other tasks, and the group lasso is a standard method for selecting a common subset of features. In this paper, we are interested in a less restrictive form of multitask learning, wherein (1) the available features can be organized into subsets according to a notion of similarity and (2) features useful in one task are similar, but not necessarily identical, to the features best suited for other tasks. The main contribution of this paper is a new procedure called Sparse Overlapping Sets (SOS) lasso, a convex optimization that automatically selects similar features for related learning tasks. Error bounds are derived for SOSlasso and its consistency is established for squared error loss. In particular, SOSlasso is motivated by multi-subject fMRI studies in which functional activity is classified using brain voxels as features. Experiments with real and synthetic data demonstrate the advantages of SOSlasso compared to the lasso and group lasso.
The Potential for Tidally Heated Icy and Temperate Moons around Exoplanets

Moons of giant planets may represent an alternative to the classical picture of habitable worlds. They may exist within the circumstellar habitable zone of a parent star, and through tidal energy dissipation they may also offer alternative habitable zones, where stellar insolation plays a secondary, or complementary, role. We investigate the potential extent of stable satellite orbits around a set of 74 known extrasolar giant planets located beyond 0.6 AU from their parent stars—where moons should be long-lived with respect to removal by stellar tides. For this sample, the typical stable satellite orbital radii span a band some ~0.02 AU in width, compared to the ~0.12-0.15 AU bands for the Jovian and Saturnian systems. Approximately 60% of these giant planets can sustain satellites or moons in bands up to ~0.04 AU in width. For comparison, the Galilean satellites extend to ~0.013 AU. We discuss how the actual number and characteristics of satellites will depend strongly on the formation pathways. We investigate the stellar insolation that moons would experience for these exoplanet systems and the implications for sublimation loss of volatiles. We find that between 15% and 27% of all known exoplanets may be capable of harboring small, icy moons. In addition, some 22%-28% of all known exoplanets could harbor moons within a "sublimation zone," with insolation temperatures between 273 and 170 K. A simplified energy-balance model is applied to the situation of temperate moons, maintained by a combination of stellar insolation and tidal heat flow. We demonstrate that large moons (>0.1 M⊕), at orbital radii commensurate with those of the Galilean satellites, could maintain temperate, or habitable, surface conditions during episodes of tidal heat dissipation of the order 1-100 times that currently seen on Io.
Mild and General Conditions for Negishi Cross-Coupling Enabled by the Use of Palladacycle Precatalysts

A wide range of biaryls were synthesized by palladium-catalyzed Negishi cross-couplings at ambient temperature or with low catalyst loading. This protocol features the use of a recently reported aminobiphenyl palladacycle precatalyst to generate the catalytically active XPhosPd(0) species. Significantly, a wide range of challenging heterocyclic and polyfluorinated aromatic substrates can be employed to give products in excellent yields.
Diagnosis and Management of Pheochromocytoma

Pheochromocytomas are rare endocrine tumors. They can be associated with a wide variety of symptoms, although hypertension is the most consistent clinical sign. Ultrasonography is very effective in localizing these tumors, but extra-adrenal pheochromocytomas are best diagnosed with 131I-metaiodobenzylguanidine scanning. Extensive investigation is ongoing to determine markers for the presence of these tumors and diagnostic tests that localize the site of pheochromocytomas, with extensive research at the molecular level. New surgical techniques are being employed, particularly laparoscopic adrenalectomy. Finally, complications of pheochromocytomas are discussed in several papers; the primary concern is cardiac problems.
Tandem rhodium catalysis: exploiting sulfoxides for asymmetric transition-metal catalysis

Sulfoxides are uncommon substrates for transition-metal catalysis due to their propensity to inhibit catalyst turnover. In a collaborative effort with Ken Houk, we developed the first dynamic kinetic resolution (DKR) of allylic sulfoxides using asymmetric rhodium-catalyzed hydrogenation. A detailed mechanistic analysis of this transformation using both experimental and theoretical methods revealed rhodium to be a tandem catalyst that promoted both hydrogenation of the alkene and racemization of the allylic sulfoxide. Using a combination of deuterium labelling and DFT studies, a novel mode of allylic sulfoxide racemization via a Rh(III)-π-allyl intermediate was identified.
Identifying the Original Contribution of a Document via Language Modeling

One major goal of text mining is to provide automatic methods to help humans grasp the key ideas in ever-increasing text corpora. To this effect, we propose a statistically well-founded method for identifying the original ideas that a document contributes to a corpus, focusing on self-referential diachronic corpora such as research publications, blogs, email, and news articles. Our statistical model of passage impact defines (interesting) original content through a combination of impact and novelty, and the model is used to identify each document's most original passages. Unlike heuristic approaches, the statistical model is extensible and open to analysis. We evaluate the approach both on synthetic data and on real data in the domains of research publications and news, showing that the passage impact model outperforms a heuristic baseline method.
SN2′ Alkylation of Cyclopropanols via Homoenolates

The stereoselective approach to the title compounds proceeds via mixed zinc/copper homoenolates of ketones.
A Census of Vertices by Generations in Regular Tessellations of the Plane

We consider regular tessellations of the plane as infinite graphs in which $q$ edges and $q$ faces meet at each vertex, and in which $p$ edges and $p$ vertices surround each face. For ${1/p + 1/q = 1/2}$, these are tilings of the Euclidean plane; for ${1/p + 1/q
The operational analysis of psychological terms

The major contributions of operationism have been negative, largely because operationists failed to distinguish logical theories of reference from empirical accounts of language. Behaviorism never finished an adequate formulation of verbal reports and therefore could not convincingly embrace subjective terms. But verbal responses to private stimuli can arise as social products through the contingencies of reinforcement arranged by verbal communities.In analyzing traditional psychological terms, we need to know their stimulus conditions (“finding the referent”), and why each response is controlled by that condition. Consistent reinforcement of verbal responses in the presence of stimuli presupposes stimuli acting upon both the speaker and the reinforcing community, but subjective terms, which apparently are responses to private stimuli, lack this characteristic. Private stimuli are physical, but we cannot account for these verbal responses by pointing to controlling stimuli, and we have not shown how verbal communities can establish and maintain the necessary consistency of reinforcement contingencies.Verbal responses to private stimuli may be maintained through appropriate reinforcement based on public accompaniments, or through reinforcements accorded responses made to public stimuli, with private cases then occurring by generalization. These contingencies help us understand why private terms have never formed a stable and uniform vocabulary: It is impossible to establish rigorous vocabularies of private stimuli for public use, because differential reinforcement cannot be made contingent upon the property of privacy. The language of private events is anchored in the public practices of the verbal community, which make individuals aware only by differentially reinforcing their verbal responses with respect to their own bodies. The treatment of verbal behavior in terms of such functional relations between verbal responses and stimuli provides a radical behaviorist alternative to the operationism of methodological behaviorists.
Gravity amplitudes from a Gaussian matrix model

We reformulate MHV scattering amplitudes in 4D gauge theory and super- gravity as correlation functions of bilinear operators in a supersymmetric gaussian matrix model. The model retains the symmetries of an S 4 of radius l and the matrix variables are represented as linear operators acting on a finite-dimensional Hilbert space. Bilinear fields of the model generate a current algebra. In the large N double scaling limit where $ {\ell_{pl }}\sim {\ell \left/ {{\sqrt{N}}} \right.} $ is held fixed, there is an emergent flat 4D space-time with a built in short distance cutoff.
Optimizing Processing Rates for Flexible Manufacturing Systems

This paper introduces the generic concept of processing rates as decision variables in Flexible Manufacturing Systems FMS's. The objective is to determine the minimum cost processing rates given the FMS throughput target, the work-in-process level, part routes, transporter delays, and the variable capacity cost function for each machine. A nonlinear Mean Value Analysis queueing network optimization methodology is developed to control bottlenecks and queue lengths as the processing rates are varied. This methodology further provides the average and marginal unit production costs along with necessary and sufficient feasibility conditions for the FMS throughput targets. Industrial sample data is then used to illustrate the solution of the optimal tool speed problem in a metal-cutting FMS. Considerable cost savings are demonstrated using the proposed methodology in contrast with the conventional one-machine optimization models. Several economic insights regarding the issues of capacity allocation for FMS's, and a generalization of the square root capacity allocation rule for closed networks of queues, are also presented.
Spectroscopy in sculpted fields

Summary Metallic and magnetic nanostructures set electromagnetic boundary conditions which can lead to highly contorted fields in their immediate vicinity. While much attention has been devoted to enhancements in electric field strength, we argue that equally interesting phenomena arise from enhancements in magnetic and electric field gradients. Nonuniform fields near nanostructures can induce molecular transitions that are forbidden by electric dipole selection rules. We illustrate this claim with two examples. “Superhelical” electromagnetic fields are predicted to show enhanced asymmetry in their interaction with chiral molecules, far greater than that due to circularly polarized light. Such fields could be used to induce chiral photochemistry with large enantiomeric excess. Steeply varying DC magnetic fields are predicted to enhance the rate of intersystem crossing in molecular bi-radicals. Such fields could provide a route to new nanomagnetic catalysts and to magnetic control of chemical reactions.
In silico synchronization of cellular populations through expression data deconvolution

Cellular populations are typically heterogenous collections of cells at different points in their respective cell cycles, each with a cell cycle time that varies from individual to individual. As a result, true single-cell behavior, particularly that which is cell-cycle--dependent, is often obscured in population-level (averaged) measurements. We have developed a simple deconvolution method that can be used to remove the effects of asynchronous variability from population-level time-series data. In this paper, we summarize some recent progress in the development and application of our approach, and provide technical updates that result in increased biological fidelity. We also explore several preliminary validation results and discuss several ongoing applications that highlight the method's usefulness for estimating parameters in differential equation models of single-cell gene regulation.
The density contrast of the Shapley supercluster

We calculate the density contrast of the Shapley supercluster (SSC) based on the enhanced abundance of X-ray clusters in it using the extended Press-Schechter formalism. We derive a total SSC mass of M tot = (4.4 ± 0.44) x 10 16 M ⊙ within a sphere of 50 Mpc centred at a distance of about 160 Mpc. The non-linear fractional density contrast of the sphere is (1 + δ) = 1.76 ± 0.17 relative to the mean matter density in the Universe, but the contrast increases in the interior of the SSC. Including the cosmological constant, the SSC region is found to be gravitationally unbound. The SSC contributes only a minor portion (9.0 ±2.1 per cent) of the peculiar velocity of the Local Group.
The early diagnosis and prevention of gastrointestinal cancer: problems and promises☆

Our goal is to eliminate gastrointestinal cancer. This may be achieved by the prevention of new tumors or by the recognition and treatment of premalignant lesions or biological early cancers. The identification of individuals at risk for gastrointestinal cancer should also involve therapies to avoid the development and progression of these tumors. Screening and surveillance Screening allows the detection of tumors when they are treatable, at an early stage of invasiveness or, even better, before they have become malignant or invasive. The importance of screening is to reduce the consequences and mortality of the tumor. Screening is one way of combating cancer. Although there are apparent benefits to screening, there are also inaccuracies and negative factors involved. The utility and reality of screening and surveillance programs in increasing life expectancy has been questioned. Craanen and Kuipers [1] point out the advantages, disadvantages, and uncertainties of mass screening and surveillance of high-risk groups. The epidemiologic problems are eloquently presented. The natural history of disease is emphasized, and it is shown how this influences the purported benefits of screening and surveillance techniques. There are limitations in detecting early lesions in asymptomatic individuals. If there is a well-defined sequential process at the time of biological onset, the disease is present but not
Competition for a Majority

We define the class of two-player zero-sum games with payoffs having mild discontinuities, which in applications typically stem from how ties are resolved. For such games, we establish sufficient conditions for existence of a value of the game, maximin and minimax strategies for the players, and a Nash equilibrium. If all discontinuities favor one player, then a value exists and that player has a maximin strategy. A property called payoff approachability implies existence of an equilibrium, and that the resulting value is invariant: games with the same payoffs at points of continuity have the same value and ?-equilibria. For voting games in which two candidates propose policies and a candidate wins election if a weighted majority of voters prefer his proposed policy, we provide tie-breaking rules and assumptions about voters' preferences sufficient to imply payoff approachability. These assumptions are satisfied by generic preferences if the dimension of the space of policies exceeds the number of voters; or with no dimensional restriction, if the electorate is sufficiently large. Each Colonel Blotto game is a special case in which each candidate allocates a resource among several constituencies and a candidate gets votes from those allocated more than his opponent offers; in this case, for simple-majority rule we prove existence of an equilibrium with zero probability of ties.
Learning Bayesian Networks: The Combination of Knowledge and Statistical Data

We describe a Bayesian approach for learning Bayesian networks from a combination of prior knowledge and statistical data. First and foremost, we develop a methodology for assessing informative priors needed for learning. Our approach is derived from a set of assumptions made previously as well as the assumption of likelihood equivalence, which says that data should not help to discriminate network structures that represent the same assertions of conditional independence. We show that likelihood equivalence when combined with previously made assumptions implies that the user's priors for network parameters can be encoded in a single Bayesian network for the next case to be seen—a prior network—and a single measure of confidence for that network. Second, using these priors, we show how to compute the relative posterior probabilities of network structures given data. Third, we describe search methods for identifying network structures with high posterior probabilities. We describe polynomial algorithms for finding the highest-scoring network structures in the special case where every node has at most k e 1 parent. For the general case (k > 1), which is NP-hard, we review heuristic search algorithms including local search, iterative local search, and simulated annealing. Finally, we describe a methodology for evaluating Bayesian-network learning algorithms, and apply this approach to a comparison of various approaches.
LUMINOUS THERMAL FLARES FROM QUIESCENT SUPERMASSIVE BLACK HOLES

A dormant supermassive black hole lurking in the center of a galaxy will be revealed when a star passes close enough to be torn apart by tidal forces, and a flare of electromagnetic radiation is emitted when the bound fraction of the stellar debris falls back onto the black hole and is accreted. Although the tidal disruption of a star is a rare event in a galaxy,≈10^(–4) yr^(–1), observational candidates have emerged in all-sky X-ray and deep ultraviolet (UV) surveys in the form of luminous UV/X-ray flares from otherwise quiescent galaxies. Here we present the third candidate tidal disruption event discovered in the Galaxy Evolution Explorer (GALEX) Deep Imaging Survey: a 1.6 × 10^(43) erg s^(–1) UV/optical flare from a star-forming galaxy at z = 0.1855. The UV/optical spectral energy distribution (SED) during the peak of the flare measured by GALEX and Palomar Large Field Camera imaging can be modeled as a single temperature blackbody with T_(bb) = 1.7 × 10^5 K and a bolometric luminosity of 3 × 10^(45) erg s^(–1), assuming an internal extinction with E(B – V)_(gas) = 0.3. The Chandra upper limit on the X-ray luminosity during the peak of the flare, L_X (2 – 10 keV) M_g > – 18.9) to predict the detection capabilities of upcoming optical synoptic surveys.
Progress on the development of APS beam position monitoring system

The authors describe the development status of the beam position monitoring system for the Advanced Photon Source (APS). The accelerator complex will consist of an electron linac, a positron linac, a positron accumulator ring (PAR), an injector synchrotron, and a storage ring. For beam position measurement, striplines will be used on the injector synchrotron and the storage ring. A test stand with a prototype injector synchrotron beam position monitor (BPM) unit has been built, and the results of position calibration measurements using a wire are presented here. The results are compared with theoretical calculations. The current effort on similar storage ring BPM system measurements is also discussed. Calibration of the APS injector synchrotron BPM pickups is complete, and results agree well with theory. >
Vulnerability Analysis of Optimized Structures

An iterative method for the analysis of damaged structures is presented in the context of the displacement method of finite-elemen t analysis, the damage is defined as the loss of stiffness of the structure. The method consists of first finding the solution of the undamaged structure and then determining the perturbed solution due to the damage by using the first two terms of the Taylor's series expansion of the initial solution. The elastic analysis of the effects of the damage, the elastoplastic analysis of the effects of material yielding, and the estimation of the loss of frequency and mode shape deterioration are the primary topics discussed. A brief discussion of a criterion for convergence of the solution and an empirical definition of the extent of damage is included. Applications of the procedure to an airplane wing structure and a truss are presented. This procedure is more economical, in most cases, than direct analysis of the structure with the damage or the usual piecewise linear analysis to include material nonlinearities.
Creating geometry and mesh models for nuclear reactor core geometries using a lattice hierarchy-based approach

Nuclear reactor cores are constructed as rectangular or hexagonal lattices of assemblies, where each assembly is itself a lattice of fuel, control, and instrumentation pins, surrounded by water or other material that moderates neutron energy and carries away fission heat. We describe a system for generating geometry and mesh for these systems. The method takes advantage of information about repeated structures in both assembly and core lattices to simplify the overall process. The system allows targeted user intervention midway through the process, enabling modification and manipulation of models for meshing or other purposes. Starting from text files describing assemblies and core, the tool can generate geometry and mesh for these models automatically as well. Simple and complex examples of tool operation are given, with the latter demonstrating generation of meshes with 12 million hexahedral elements in less than 30 minutes on a desktop workstation, using about 4 GB of memory. The tool is released as open source software as part of the MeshKit mesh generation library.
Data-model comparison using FORWARD and CoMP

The FORWARD SolarSoft IDL package is a community resource for model-data comparison, with a particular emphasis on analyzing coronal magnetic fields. FORWARD allows the synthesis of coronal polarimetric signals at visible, infrared, and radio frequencies, and will soon be augmented for ultraviolet polarimetry. In this paper we focus on observations of the infrared (IR) forbidden lines of Fe XIII, and describe how FORWARD may be used to directly access these data from the Mauna Loa Solar Observatory Coronal Multi-channel Polarimeter (MLSO/CoMP), to put them in the context of other spaceand ground-based observations, and to compare them to synthetic observables generated from magnetohydrodynamic (MHD) models.
Investigations into arylquinone atropisomers: synthesis and evaluation

An arylquinone capable of existing as two diastereromeric atropisomers was synthesized starting from dibenzofuran. Arylquinone 12 exists as a set of slowly interchanging diastereomeric atropisomers and arylquinone 4 exists as rapidly interchanging atropisomers.
Direct α-heteroarylation of amides (α to nitrogen) and ethers through a benzaldehyde-mediated photoredox reaction

A photoredox reaction for cross-dehydrogenative coupling (CDC) was developed to Cα-arylate amides (α to nitrogen) and ethers using a variety of five- and six-membered electron-deficient heteroarenes. A unique decomposition mechanism of ammonium persulfate enhanced by photoexcited benzaldehydes was revealed. This benzaldehyde-mediated photoredox reaction proceeded smoothly with household 23 W CFL bulbs as the energy source under metal-free conditions, allowing the construction of new Csp2 -Csp2 and Csp3 -Csp2 bonds and access to important pharmacophores of broad utility using commercially available reagents.
Hydrodynamic thrust generation and power consumption investigations for piezoelectric fins with different aspect ratios

Bio-inspired hydrodynamic thrust generation using piezoelectric transduction has recently been explored using Macro-Fiber Composite (MFC) actuators. The MFC technology strikes a balance between the actuation force and structural deformation levels for effective swimming performance, and additionally offers geometric scalability, silent operation, and ease of fabrication. Recently we have shown that mean thrust levels comparable to biological fish of similar size can be achieved using MFC fins. The present work investigates the effect of length-to-width (L/b) aspect ratio on the hydrodynamic thrust generation performance of MFC cantilever fins by accounting for the power consumption level. It is known that the hydrodynamic inertia and drag coefficients are controlled by the aspect ratio especially for L/b< 5. The three MFC bimorph fins explored in this work have the aspect ratios of 2.1, 3.9, and 5.4. A nonlinear electrohydroelastic model is employed to extract the inertia and drag coefficients from the vibration response to harmonic actuation for the first bending mode. Experiments are then conducted for various actuation voltage levels to quantify the mean thrust resultant and power consumption levels for different aspect ratios. Variation of the thrust coefficient of the MFC bimorph fins with changing aspect ratio is also semi-empirically modeled and presented.
Optimizing water quality sampling through application of real time ionic concentration regression models

The Water Resources Management Division of the Department of Environment and Conservation performs routine water sampling to measure the physical and chemical parameters of select water bodies in Newfoundland and Labrador. Ionic concentration parameter measurement is performed during routine water sampling to complement some of the key indicator parameters measured in real time at these select water bodies. The collection, laboratory analysis and measurement of water samples are a time consuming process. Some of the common conducting ions measured during routine sampling are sodium, calcium, chloride and sulphate. These conducting ions can be estimated using continuously measured specific conductance after observing the effect of flow. The estimated measurement will help identify whether any local stressors are affecting the quality of water at a given point in time and hence save time and resources in performing routine sampling. This can also be applied in remote locations where routine sampling is not feasible. This paper compares four water bodies on the island part of Newfoundland and Labrador and estimates the ionic concentration using continuously measured specific conductance.