cssi/SciSciGPT-SciSciNet huggingface dataset:
The Choice Between Joint Ventures and Acquisitions: Insights from Signaling Theory

This paper extends information economics in corporate strategy and organizational governance research by using signaling theory to explain firms' market entry modes. We exploit features of the initial public offering (IPO) context to investigate how signals on newly public firms shape other companies' governance choices to form joint ventures with them versus acquiring them. We also develop theoretical arguments on how the value of these signals will vary across exchange partners. The results reveal that companies are more apt to acquire, versus partner with, IPO firms taken public by reputable investment banks compared with IPO firms associated with less prominent underwriters. Venture capitalist backing also appears to be a valuable signal for prospective acquirers, particularly when the acquirer and target reside in different industries and possess dissimilar knowledge bases. We also present evidence that signals affect target selection and the emergence of market segmentation for joint venture partners and acquisition candidates.
Electrodynamic properties of single-crystal and thin-film strontium titanate

Abstract We present a comparative study of broadband electrodynamic properties of coplanar waveguides made from nonlinear dielectric single-crystal and thin-film SrTiO3 (STO) with high-temperature superconducting thin-film YBa2Cu3O7-δ electrodes. The waveguides that use single-crystal STO exhibit a monotonic increase in refractive index, dielectric nonlinearity, and dissipation with decreasing temperature (from 80 K to 20 K), whereas those based on thin-film STO show similar but weaker effects with increasing temperature. Under dc bias, both types of waveguides show reduced refractive index, but dissipation increases in the case of single-crystal STO, while it decreases in the case of STO thin-films.
Edge-colorings of complete graphs that avoid polychromatic trees

Given a positive integer n and a family F of graphs, let R^*(n,F) denote the maximum number of colors in an edge-coloring of K"n such that no subgraph of K"n belonging to F has distinct colors on its edges. We determine R^*(n,T"k), where T"k is the family of trees with k edges. We derive general bounds for R^*(n,T), where T is an arbitrary tree with k edges. Finally, we present a single tree T with k edges such that R^*(n,T) is nearly as small as R^*(n,T"k).
Semiconductor nanowires: A platform for nanoscience and nanotechnology

Advances in nanoscience and nanotechnology critically depend on the development of nanostructures whose properties are controlled during synthesis. We focus on this critical concept using semiconductor nanowires, which provide the capability through design and rational synthesis to realize unprecedented structural and functional complexity in building blocks as a platform material. First, a brief review of the synthesis of complex modulated nanowires in which rational design and synthesis can be used to precisely control composition, structure, and, most recently, structural topology is discussed. Second, the unique functional characteristics emerging from our exquisite control of nanowire materials are illustrated using several selected examples from nanoelectronics and nano-enabled energy. Finally, the remarkable power of nanowire building blocks is further highlighted through their capability to create unprecedented, active electronic interfaces with biological systems. Recent work pushing the limits of both multiplexed extracellular recording at the single-cell level and the first examples of intracellular recording is described, as well as the prospects for truly blurring the distinction between nonliving nanoelectronic and living biological systems.
The partial death of abortion rights.

On April 18, the Supreme Court held in Gonzales v. Carhart that a federal statute outlawing the use of “partial-birth abortion” is constitutional. R. Alta Charo writes that the decision thus opens the door to revisiting any number of state and federal efforts to restrict access to abortion services. LeRoy Carhart of Nebraska and attorney Priscilla Smith who argued Gonzales v. Carhart before the Supreme Court, discuss the clinical and practical implications of the Court's recent decision to uphold the federal Partial-Birth Abortion Ban Act. LeRoy Carhart is a physician and abortion provider in Bellevue, Nebraska. Priscilla Smith is an attorney formerly associated with the Center for Reproductive Rights in New York.
Workers, Warriors and Criminals: Social Conflict in General Equilibrium

We analyze how economy-wide forces (i.e.shocks to terms of trade, technology and endowments) affect the intensity of social conflict. We see conflict phenomena such as crime and civil war as involving resource appropriation activities. We show that not all shocks that could make society richer will reduce conflict. Positive shocks to labor intensive industries will diminish social conflict, while positive shocks to capital intensive industries will increase it. The key requirement is that appropriation activities be more labor intensive than the economy. Our model can explain the positive association between crime and inequality, and the curse of natural resources; it predicts that aid in kind to war-ridden societies will have perverse effects, and offers guidance on how to integrate international trade policy and peacekeeping efforts. Including appropriation activities into a canonic general equilibrium model introduces a social constraint to policy analysis. Thus, we can also account for populist policies, apparently inefficient redistribution and “national development strategies”.
Modulation of T cell function through L-arginine metabolism: a new therapy from an old enemy

Recent studies have suggested the relevance of different energy metabolic pathways in the balance between protective T cell immunity and T cell anergy in tumors. We and others have suggested the role of the depletion of the non-essential amino acid L-arginine as a mechanism for the induction of T cell suppression in tumors. Therefore, we hypothesize that it is possible to metabolically regulate T cell responses simply through the modulation of L-arginine. In this study, we aimed to determine the effect of a pegylated form of the human L-arginine-metabolizing enzyme arginase I (peg-Arg I) in T cell responses. Activation of antigen-specific CD4+ and CD8+ T cells in the presence of peg-Arg I prevented cell proliferation and production of IFNγ in vitro and in vivo. Similarly, peg-Arg I impaired proliferation and IFNγ production in T cells activated with PMA/Ionomycin, suggesting that the effect of peg-Arg I was independent of T cell receptor (TCR) signaling. In fact, the anti-proliferative effect induced by peg-Arg I correlated with an arrest of T cells in the G0-G1 phase of the cell cycle, a decreased expression of cyclin D3 and cdk4, and a major inhibition of de novo translation. Interestingly, treatment of T cells with peg-Arg I did not impair the expression of activation markers CD25, CD69, and the production of IL-2, which correlated with an intact mitochondrial biogenesis. As a result, peg-Arg I did not have an effect in oxygen consumption (OCR) by mitochondrial respiration, but significantly blocked glycolytic pathways in activated T cells. Furthermore, peg-Arg I treated T cells increased the expression of genes associated with integrated stress responses (IRS) and arrest in translation including GCN2, Chop, and Atf4. In fact, GCN2 was a major mediator of the effects induced by peg-Arg I. Then, we tested the effect of peg-Arg I in mouse models of graft versus host disease (GVHD) and inflammatory bowel disease (IBD), both mediated through activated T cells. Peg-Arg I significantly extended the survival of mice in these 2 disease models, which associated with a decreased production of IFNγ. Altogether the results suggest the potential effect of the modulation of the metabolism of L-arginine as a mean to modulate T cell responses. Continuation of this study will advance in the understanding of the metabolic effects of L-arginine in T cell function, which could enable the development of therapies to modulate T cell responses in transplantation or autoimmunity.
Effects of aridity and vegetation on plant-wax δD in modern lake sediments

We analyzed the deuterium composition of individual plant-waxes in lake sediments from 28 watersheds that span a range of precipitation D/H, vegetation types and climates. The apparent isotopic fractionation (ea) between plant-wax n-alkanes and precipitation differs with watershed ecosystem type and structure, and decreases with increasing regional aridity as measured by enrichment of 2 H and 18 O associated with evaporation of lake waters. The most negative ea values represent signatures least affected by aridity; these values were � 125 ± 5& for tropical evergreen and dry forests, � 130& for a temperate broadleaf
Export Growth and Credit Constraints

We investigate the magnitude and the persistence of the effect of credit constraints on the growth of exports at a micro level. We develop a model showing credit constraints play a key role in early stages of exporting, with their role on the growth rate of exports diminishing as exporting continues. Our empirical results using data on exports to twelve European Union countries and the U.S. at the product level confirm the model’s predictions: exports from less developed financial systems and from industries more reliant on external financing and with more tangible assets grow faster, while the growth rate decreases with age and converges across countries with age. The effect of credit constraints on the growth of exports disappears relatively quickly, within the first three years of exporting.
Computational prediction of hinge axes in proteins

A protein's function is determined by the wide range of motions exhibited by its 3D structure. However, current experimental techniques are not able to reliably provide the level of detail required for elucidating the exact mechanisms of protein motion essential for effective drug screening and design. Computational tools are instrumental in the study of the underlying structure-function relationship. We focus on a special type of proteins called "hinge proteins" which exhibit a motion that can be interpreted as a rotation of one domain relative to another. This work proposes a computational approach that uses the geometric structure of a single conformation to predict the feasible motions of the protein and is founded in recent work from rigidity theory, an area of mathematics that studies flexibility properties of general structures. Given a single conformational state, our analysis predicts a relative axis of motion between two specified domains. We analyze a dataset of 19 structures known to exhibit this hinge-like behavior. For 15, the predicted axis is consistent with a motion to a second, known conformation. We present a detailed case study for three proteins whose dynamics have been well-studied in the literature: calmodulin, the LAO binding protein and the Bence-Jones protein. Our results show that incorporating rigidity-theoretic analyses can lead to effective computational methods for understanding hinge motions in macromolecules. This initial investigation is the first step towards a new tool for probing the structure-dynamics relationship in proteins.
Protocol architecture for multimedia applications over ATM networks

At the data-link layer, ATM offers a number of features, such as high-bandwidth and per-session quality-of-service (QoS) guarantees, making it particularly attractive to multimedia applications. Unfortunately, many of these features are not visible to applications because of the inadequacies of existing higher-level protocol architectures. Although there is considerable effort underway to tune these protocols for ATM networks, we believe that a new ATM-specific protocol stack is essential to effectively exploit all the benefits of ATM. We describe the semantics of such a protocol stack, and discuss its advantages over traditional protocol architectures from the perspective of multimedia applications. The performance impact of the new protocol architecture is experimentally demonstrated on a video conferencing testbed built around IBM RS/6000's equipped with prototype hardware for video/audio processing, and connected via ATM links.
Quantum bouncer with quadratic dissipation

The energy loss due to a quadratic velocity-dependent force on a quantum particle bouncing off a perfectly reflecting surface is obtained for a full cycle of motion. We approach this problem by means of a new, effective, phenomenological Hamiltonian which corresponds to the actual energy of the system and obtain the correction to the eigenvalues of the energy in first-order quantum perturbation theory for the case of weak dissipation.
MODEL CATEGORY STRUCTURES ON CHAIN COMPLEXES OF SHEAVES

In this paper, we try to determine when the derived category of an abelian category is the homotopy category of a model structure on the category of chain complexes. We prove that this is always the case when the abelian category is a Grothendieck category, as has also been done by Morel. But this model structure is not very useful for dening derived tensor products. We therefore consider another method for constructing a model structure, and apply it to the category of sheaves on a well-behaved ringed space. The resulting flat model structure is compatible with the tensor product and all homomorphisms of ringed spaces.
Middle atmosphere tides

Abstract Recent progress in the study of middle atmosphere tides is reviewed. Specific areas where recent progress has occurred include: development of more realistic thermal excitation and numerical simulation models; the role of tides in accelerating and heating the mean flow at the base of the thermosphere; observational efforts which delineate average seasonal, latitudinal and vertical structures of tides, and shorterterm variations of tides about these values; theoretical and observational studies concerning the importance of non-migrating tidal components; the effects of tides on minor constituent concentrations in the upper mesosphere and lower thermosphere. The review concludes with a summary of key problems to be addressed in the future.
Analysing partition: Definition, classification and explanation

Abstract Political partitions should be carefully distinguished from secessions, de-colonizations and disengagements—though they may accompany these phenomena. Political partitions involve a fresh cut, an at least partially novel border, ripped through at least one national community's homeland. Partitions of national and multinational polities may be distinguished, as may external and internal partitions. External partitions have been rarer than suggested in conventional accounts, and explanations of their occurrence are evaluated, and recommendations are made that their rarity should persist.
A simplified way of proving trade-off results for resolution

We present a greatly simplified proof of the length-space trade-off result for resolution in [P. Hertel, T. Pitassi, Exponential time/space speedups for resolution and the PSPACE-completeness of black-white pebbling, in: Proceedings of the 48th Annual IEEE Symposium on Foundations of Computer Science (FOCS '07), Oct. 2007, pp. 137-149], and also prove a couple of other theorems in the same vein. We point out two important ingredients needed for our proofs to work, and discuss some possible conclusions. Our key trick is to look at formulas of the type [email protected]?H, where G and H are over disjoint sets of variables and have very different length-space properties with respect to resolution.
Rendezvous radar for the orbital maneuvering vehicle

The rendezvous radar set (RRS) under development will be a key subsystem aboard NASA's new orbital maneuvering vehicle (OMV). The RRS is an X-band all solid-state, monopulse tracking, frequency-hopping, pulse-Doppler radar system. Targets of 1 m/sup 2/ are detected at ranges greater than 4.5 nautical miles, and larger targets are detected at up to 10 nautical miles. The target is then tracked in angle, range, and range rate to a distance of 35 feet from the OMV. In addition to performance and cost, the design drivers for the RRS development have included the minimization of power consumption, size, and weight. >
Demographics and Aggregate Household Saving in Japan, China, and India

Abstract We use a model of household life-cycle saving decisions to quantify the impact of demographic changes on aggregate household saving rates in Japan, China, and India. The observed age distributions help explain the contrasting saving patterns over time across the three countries. In the model simulations, the growing number of retirees suppresses Japanese saving rates, while decreasing family size increases saving for both China and India. Projecting forward, the model predicts a decline in household saving rates in Japan and China.
Classification of Finite-Growth General Kac–Moody Superalgebras

A contragredient Lie superalgebra is a superalgebra defined by a Cartan matrix. A contragredient Lie superalgebra has finite-growth if the dimensions of the graded components (in the natural grading) depend polynomially on the degree. In this article we classify finite-growth contragredient Lie superalgebras. Previously, such a classification was known only for the symmetrizable case.
Intercept point and undesired responses

A method for using the concept of intercept point to calculate the undesired-response rejection ratio of a single stage is presented. Single stages may be cascaded together to form a system and the undesired-response rejection ratio of the system may be found using a procedure similar to cascaded noise figure. When applied to receiver system design, this method allows easy calculation of such undesired receiver responses as intermodulation distortion and spurious responses.
Copper-Catalyzed Formation of α-Alkoxycycloalkenones from N-Tosylhydrazones.

The combination of 20 mol % of copper iodide and lithium tert-butoxide triggers the formation of a broad range of substituted, functionalized α-alkoxy 2H-naphthalenones from readily available N-tosylhydrazones. The data suggests that this transformation occurs through cycloaddition of a copper carbenoid with an ester, followed by a Lewis acid-catalyzed [1,2] alkyl shift of the in situ generated alkoxyepoxide intermediate.
Palladium-catalyzed trifluoroacetate-promoted mono-arylation of the β-methyl group of alanine at room temperature: synthesis of β-arylated α-amino acids through sequential C–H functionalization

We report a highly efficient and practical protocol for palladium-catalyzed N-quinolylcarboxamide (AQ)-directed arylation of the unactivated β-C(sp3)–H bonds of alanine with aryl iodides at room temperature. For the first time, a broad range of easily accessible aryl iodides can be installed onto the β-methyl group of AQ-coupled phthaloyl alanine mono-selectively, providing both natural and unnatural aromatic α-amino acids. Access to these mono-arylated compounds enables subsequent AQ-directed diastereoselective C–H functionalization, allowing the preparation of various β-disubstituted aromatic α-amino acids in a programmable manner.
Thermodynamic limit for large random trees

We consider Gibbs distributions on finite random plane trees with bounded branching. We show that as the order of the tree grows to infinity, the distribution of any finite neighborhood of the root of the tree converges to a limit. We compute the limiting distribution explicitly and study its properties. We introduce an infinite random tree consistent with these limiting distributions and show that it satisfies a certain form of the Markov property. We also study the growth of this tree and prove several limit theorems including a diffusion approximation. © 2010 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Network formation by reinforcement learning: the long and medium run

Abstract We investigate a simple stochastic model of social network formation by the process of reinforcement learning with discounting of the past. In the limit, for any value of the discounting parameter, small, stable cliques are formed. However, the time it takes to reach the limiting state in which cliques have formed is very sensitive to the discounting parameter. Depending on this value, the limiting result may or may not be a good predictor for realistic observation times.
Singular perturbation in piecewise-linear systems

A singular perturbation technique is developed that allows for a decoupling of a continuous piecewise-linear system into slow and fast subsystems. Under the assumption of asymptotic stability, the fast variable is found to decay in the boundary layer to its quasi-steady-state solution, which is given by a continuous implicit function of the slow variable. The solution is found using a finite step algorithm. Sufficient conditions for the approximation to be accurate to an order of O( mu ), where mu is a parameter of the system, are given. The technique is illustrated by a numerical example. >
Preparation and Characterization of Fast Ion Conducting Lithium Thio-Germanate Thin Films Grown by RF Magnetron Sputtering

In this study, amorphous lithium thio-germanate thin films were prepared by radio frequency (RF) sputtering deposition in Ar atmospheres. For the first time, new high quality lithium germanium sulfide nLi2S þGeS2 thin films, n ¼1, 2, and 3, have been successfully made by RF sputtering and synthesized as new solid state electrolytes. Although these materials are unstable in air, the starting materials, target materials, and thin films made from them were thoroughly characterized by x-ray diffraction (XRD), Raman spectroscopy, SEM, x-ray photoelectron spectroscopy (XPS), and impedance spectroscopy using special setups to prevent contamination. These high quality thin films did not show any cracks and pits on the surface and the ionic conductivities of the thin films are 2‐3 orders of magnitude higher than reported values for similar lithium containing oxide thin films. In this way, this work may provide a new way for developing new thin-film electrolytes for solid state lithium ion batteries.
No way out? The double-bind in seeking global prosperity alongside mitigated climate change

Abstract. In a prior study (Garrett, 2011), I introduced a simple economic growth model designed to be consistent with general thermodynamic laws. Unlike traditional economic models, civilization is viewed only as a well-mixed global whole with no distinction made between individual nations, economic sectors, labor, or capital investments. At the model core is a hypothesis that the global economy's current rate of primary energy consumption is tied through a constant to a very general representation of its historically accumulated wealth. Observations support this hypothesis, and indicate that the constant's value is λ = 9.7 ± 0.3 milliwatts per 1990 US dollar. It is this link that allows for treatment of seemingly complex economic systems as simple physical systems. Here, this growth model is coupled to a linear formulation for the evolution of globally well-mixed atmospheric CO2 concentrations. While very simple, the coupled model provides faithful multi-decadal hindcasts of trajectories in gross world product (GWP) and CO2. Extending the model to the future, the model suggests that the well-known IPCC SRES scenarios substantially underestimate how much CO2 levels will rise for a given level of future economic prosperity. For one, global CO2 emission rates cannot be decoupled from wealth through efficiency gains. For another, like a long-term natural disaster, future greenhouse warming can be expected to act as an inflationary drag on the real growth of global wealth. For atmospheric CO2 concentrations to remain below a "dangerous" level of 450 ppmv (Hansen et al., 2007), model forecasts suggest that there will have to be some combination of an unrealistically rapid rate of energy decarbonization and nearly immediate reductions in global civilization wealth. Effectively, it appears that civilization may be in a double-bind. If civilization does not collapse quickly this century, then CO2 levels will likely end up exceeding 1000 ppmv; but, if CO2 levels rise by this much, then the risk is that civilization will gradually tend towards collapse.
Operating Experience Review of Tritium-in-Water Monitors

Abstract Monitoring tritium facility and fusion experiment effluent streams is an environmental safety requirement. This paper presents data on the operating experience of a solid scintillant monitor for tritium in effluent water. Operating experiences were used to calculate an average monitor failure rate of 4E−05/h for failure to function. Maintenance experiences were examined to find the active repair time for this type of monitor, which varied from 22 min for filter replacement to 11 days of downtime while waiting for spare parts to arrive on site. These data support planning for monitor use; the number of monitors needed, allocating technician time for maintenance, inventories of spare parts, and other issues.
Biofuel Cell Anodes Integrating NAD+-Dependent Enzymes and Multiwalled Carbon Nanotube Papers

The enzymatic biofuel cells are devices capable of harvesting chemical energy of organic compounds to generate electrical energy to power small portable devices. The limitation of such system is due to kinetic, ohmic and mass transport losses. The performance of the biofuel cell would be improved by improving the activity of the catalytic layer by increasing the surface area and enzyme load/ immobilization of the enzymes on the surface of the electrode, by decreasing the ohmic losses through the integration of highly conductive nanomaterials, and by decreasing the mass transport loses while applying a microfluidic system capable of feeding the biofuel to the bioelectrode. Optimum electrodes materials must simultaneously satisfy several criteria such as high electrical conductivity, significant attractive interactions with enzymes, high surface to volume ratio, and sufficiently large pore size to facilitate mass transport 6, . Additionally, high controlled surface chemistry must be satisfied. Carbon nanotubes are promising electrode materials for biofuel cells because of the combination of their high electrical conductivity, mechanical strength, thermal stability and chemical stability.
Software Architectures for Task-Oriented Computing

Summary form only given. Recent advances in ubiquitous computing, autonomic computing, and artificial intelligence have led to a desire to better support user-oriented tasks by placing more intelligence in the computing infrastructure. This infrastructure helps mediate between computing resources and legacy applications on the one hand, and a user's high-level goals on the other hand. In this talk I survey recent research in developing software architectures to support these new capabilities. Key features of these architectures are the ability to interface with legacy applications, but still add considerable support for user tasks; the ability to incorporate machine learning so that the system adapts to the user over time; and the ability to cope with resource variability and user mobility. I outline some of the consequent software engineering challenges that arise in this setting.
Contemporaneous perfect epsilon-equilibria

We examine contemporaneous perfect "-equilibria, in which a player’s actions after every history, evaluated at the point of deviation from the equilibrium, must be within " of a best response. This concept implies, but is stronger than, Radner’s ex ante perfect "-equilibrium. A strategy profile is a contemporaneous perfect "equilibrium of a game if it is a subgame perfect equilibrium in a perturbed game with nearly the same payos, with the converse holding for pure equilibria.
Timing of Product Allocation: Using Probabilistic Selling to Enhance Inventory Management

This paper examines probabilistic selling PS as an inventory-management mechanism, paying special attention to the impact of the timing of product assignment to buyers of probabilistic goods. In practice, sellers tend to offer probabilistic products only after major demand uncertainty has been resolved. By deferring product assignments, a firm is able to obtain more information about demand for each specific product before deciding which product to assign to consumers. However, our analysis demonstrates that PS can be an effective inventory-management mechanism even if the firm allocates products before knowing which product will be more popular and, thus, scarcer. Interestingly, we show that it can be more profitable for the firm to allocate products to consumers before, rather than after, learning the true demand for a product because, although early allocation imposes higher inventory costs as a result of larger required inventory levels, it also enables the firm to charge higher prices. Our results also reveal that, when introducing probabilistic goods, the firm should order less inventory relative to the case where probabilistic goods are not offered if costs are very low but more inventory otherwise. Finally, we show that PS, as an inventory-management mechanism, can create a win--win situation, both improving profit and increasing social welfare. This paper was accepted by J. Miguel Villas-Boas, marketing.
"IRRATIONAL" PLANTING BEHAVIOR AS RATIONAL EXPECTATIONS OF GOVERNMENT SUPPORT

The paper outlines an approach to estimation of rational expectations acreage response model for US soybeans that explicitly takes into account government payments. Numerical methods are used to recompute the model equilibrium at each iteration of the log-likelihood optimization routine. Estimation results allow one to measure market distortion introduced by the government support programs.
Ion Temperatures in the Low Solar Corona: Polar Coronal Holes at Solar Minimum

In the present work we use a deep-exposure spectrum taken by the SUMER spectrometer in a polar coronal hole in 1996 to measure the ion temperatures of a large number of ions at many different heights above the limb between 0.03 and 0.17 solar radii. We find that the measured ion temperatures are almost always larger than the electron temperatures and exhibit a nonmonotonic dependence on the charge-to-mass ratio. We use these measurements to provide empirical constraints to a theoretical model of ion heating and acceleration based on gradually replenished ion-cyclotron waves. We compare the wave power required to heat the ions to the observed levels to a prediction based on a model of anisotropic magnetohydrodynamic turbulence. We find that the empirical heating model and the turbulent cascade model agree with one another, and explain the measured ion temperatures, for charge-to-mass ratios smaller than about 0.25. However, ions with charge-to-mass ratios exceeding 0.25 disagree with the model; the wave power that they require to be heated to the measured ion temperatures shows an increase with charge-to-mass ratio (i.e., with increasing frequency) that cannot be explained by a traditional cascade model. We discuss possible additional processes that might be responsible for the inferred surplus of wave power.
Cointegration Analysis of Unbiased Expectations in the BIFFEX Freight Futures Market

The continued survival of the Baltic International Freight Futures Exchange (BIFFEX), based at the London International Financial Futures Exchange (LIFFE), has come as a surprise to many critics of this unique futures market (the only futures contract on a service). The level of trading activity remains low and the number of players limited, and as a result, this has disappointed advocates of the use of derivatives in the shipping market. Therefore, in an effort to explain, at least partially, the reasons for its continued success, this paper tests long-term and short-term unbiasedness in the freight futures market with respect to its ability to unbiasedly predict future spot prices, using cointegration and error-correction techniques. Findings show that results from cointegrating regressions may falsely lead to the acceptance of unbiasedness by ignoring short-term dynamics. Results confirm that the freight futures market is "long-term" efficient but does experience "short-term" deviations. In light of these results, recent market developments are discussed.
Syntheses Of (±)-Raikovenal, (±)-Preraikovenal, and (±)-Epiraikovenal

Abstract (±)-Raikovenal (1a) has been synthesized in five steps from dihydrofilifolone (3) by two Wittig reactions. A similar sequence provides (±)-preraikovenal from aldehyde 11. Epiraikovenal (1b) has been prepared by photolysis of preraikovenal or by photolysis of 5 to give 4b. Lewis acid induced cyclization of enal 5 gives cyclopentylideneacetaldehyde 16 rather than bicyclo[3.2.0]heptanecarboxaldehyde 4.
STRUCTURAL ESTIMATION OF SEQUENTIAL GAMES OF COMPLETE INFORMATION

In models of strategic interaction, there may be important order of entry effects if one player can credibly commit to an action (e.g., entry) before other players. If one esti- mates a simultaneous-move model, then the move-order effects will be confounded with the payoffs. This paper considers nonparametric identification and simulation-based estimation of sequential games of complete information. Relative to simultaneous-move games, these models avoid the problem of multiple equilibria and require fewer payoff normalizations. We apply the estimator in several Monte Carlo experiments and to study entry-order effects using data from the airline industry.
Algorithms for geodesics

Algorithms for the computation of geodesics on an ellipsoid of revolution are given. These provide accurate, robust, and fast solutions to the direct and inverse geodesic problems and they allow differential and integral properties of geodesics to be computed.
GPU-accelerated Chemical Similarity Assessment for Large Scale Databases

The assessment of chemical similarity between molecules is a basic operation in chemoinformatics, a computational area concerning with the manipulation of chemical structural information. Comparing molecules is the basis for a wide range of applications such as searching in chemical databases, training prediction models for virtual screening or aggregating clusters of similar compounds. However, currently available multimillion databases represent a challenge for conventional chemoinformatics algorithms raising the necessity for faster similarity methods. In this paper, we extensively analyze the advantages of using many-core architectures for calculating some commonly-used chemical similarity coefficients such as Tanimoto, Dice or Cosine. Our aim is to provide a wide-breath proof-of-concept regarding the usefulness of GPU architectures to chemoinformatics, a class of computing problems still uncovered. In our work, we present a general GPU algorithm for all-to-all chemical comparisons considering both binary fingerprints and floating point descriptors as molecule representation. Subsequently, we adopt optimization techniques to minimize global memory accesses and to further improve efficiency. We test the proposed algorithm on different experimental setups, a laptop with a low-end GPU and a desktop with a more performant GPU. In the former case, we obtain a 4-to-6-fold speed-up over a single-core implementation for fingerprints and a 4-to-7-fold speed-up for descriptors. In the latter case, we respectively obtain a 195-to-206-fold speed-up and a 100-to-328-fold speed-up.
Electro-Optic Imaging Fourier Transform Spectrometer

JPL is developing an innovative compact, low mass, electro-optic imaging Fourier transform spectrometer (E-O IFTS) for hyperspectral imaging applications. The spectral region of this spectrometer will be 1-2.5 mum (1000 - 4000 cm-1) to allow high-resolution, high-speed hyperspectral imaging applications. The specific applications for NASA's missions will focus on the measurement of a large number of different atmospheric gases simultaneously in the same airmass. Due to the use of a combination of birefringent phase retarders and multiple achromatic phase switches to achieve phase delay, this spectrometer is capable of hyperspectral measurements similar to that of the conventional Fourier transform spectrometer but without any moving parts. In this paper, the principle of operations, system architecture and recent experimental progress were presented.
Recommendations Using Information from Multiple Association Rules: A Probabilistic Approach

Business analytics has evolved from being a novelty used by a select few to an accepted facet of conducting business. Recommender systems form a critical component of the business analytics toolkit and, by enabling firms to effectively target customers with products and services, are helping alter the e-commerce landscape. A variety of methods exist for providing recommendations, with collaborative filtering, matrix factorization, and association-rule-based methods being the most common. In this paper, we propose a method to improve the quality of recommendations made using association rules. This is accomplished by combining rules when possible and stands apart from existing rule-combination methods in that it is strongly grounded in probability theory. Combining rules requires the identification of the best combination of rules from the many combinations that might exist, and we use a maximum-likelihood framework to compare alternative combinations. Because it is impractical to apply the maximum likelihood framework directly in real time, we show that this problem can equivalently be represented as a set partitioning problem by translating it into an information theoretic context-the best solution corresponds to the set of rules that leads to the highest sum of mutual information associated with the rules. Through a variety of experiments that evaluate the quality of recommendations made using the proposed approach, we show that i a greedy heuristic used to solve the maximum likelihood estimation problem is very effective, providing results comparable to those from using the optimal set partitioning solution; ii the recommendations made by our approach are more accurate than those made by a variety of state-of-the-art benchmarks, including collaborative filtering and matrix factorization; and iii the recommendations can be made in a fraction of a second on a desktop computer, making it practical to use in real-world applications.
Cartesian control of robotic manipulators with joint compliance

An efficient on-line scheme for computing the inverse joint solution of robotic manipulators is combined with an improved formulation of robust, non-linear feedback control in joint space to produce a realizable Cartesian control scheme. Parametric uncertainties in the robot model are highlighted by the inclusion of compliance at each joint. Simulation results for a two link, coupled manipulator demonstrate that this Cartesian control enables the tip of the arm to track the demanded trajectory with arbitrarily small error in response to realistic actuator torques.
London penetration depth in iron-based superconductors

Measurements of London penetration depth, a sensitive tool to study multiband superconductivity, have provided several important insights into the behavior of Fe-based superconductors. We first briefly review the 'experimentalist-friendly' self-consistent Eilenberger two-band model that relates the measurable superfluid density and temperature dependences of the superconducting gaps. Then we focus on BaFe2As2-derived materials, for which the results are consistent with (1) two distinct superconducting gaps; (2) development of strong in-plane gap anisotropy with departure from optimal doping; (3) development of gap nodes along the c direction in a highly overdoped regime; (4) significant pair-breaking, presumably due to charge doping; (5) fully gapped intrinsic behavior (exponential at low temperatures) at optimal doping if the scattering is removed (probed in the 'self-doped' stoichiometric LiFeAs); (6) competition between the magnetically ordered state and superconductivity, which do coexist in underdoped compounds. Overall, it appears that while there are common trends in the behavior of Fe-based superconductors, the gap structure is non-universal and is quite sensitive to the doping level. It is plausible that the rich variety of possible gap structures within the general s± framework is responsible for the observed behavior.
In Situ Characterization of Positive Resist Development

The exposure of certain positive photoresists has been shown by Dill and co-workers to be modelable in terms of a local inhibitor concentration which results in a local development rate. The development process is assumed to be a surface etching reaction in which the surface velocity is the local development rate. The characterization of resists for the purpose of line-edge profile simulation therefore involves the measurement of development rate for controlled exposure dose profiles. In this paper a technique is described in which the resist thickness is continuously plotted during development. The low frequency capacitance is measured using a conducting substrate as one plate, and the highly conductive developer as the other plate of the capacitor. The inverse capacitance, proportional to the composite resist-oxide thickness, is obtained using an analog divider. Examples of standing wave effects in Shipley AZ 1350 resists, and resist development rate modification using chlorobenzene are presented.
The single family home in the investment portfolio

This article uses recent measures of the risk and return to investment in housing to estimate the effects of including a single family home in the investor portolio. We estimate the expected return and standard deviation of that return, as well as its correlation with other major investment classes.
On the effect of localization errors on geographic face routing in sensor networks

In the absence of location errors, geographic routing - using a combination of greedy forwarding and face routing - has been shown to work correctly and efficiently. The effects of location errors on geographic routing have not been studied before. In this work we provide a detailed analysis of the effects of location errors on the correctness and performance of geographic routing in static sensor networks. First, we perform a micro-level behavioral analysis to identify the possible protocol error scenarios and their conditions and bounds. Then, we present results from an extensive simulation study of GPSR and GHT to quantify the performance degradation due to location errors. Our results show that even small location errors (of 10% of the radio range or less) can in fact lead to incorrect (non-recoverable) geographic routing with noticeable performance degradation. We then introduce a simple modification for face routing that eliminates probable errors and leads to near perfect performance.
Organizational Form and Accounting Choice: Are Nonprofit or For-Profit Managers More Aggressive?

ABSTRACT: Although recent academic studies on nonprofits have documented aggressive accounting behavior, these studies have primarily examined the sector in isolation and have not reached definitive conclusions regarding the relative aggressiveness of the nonprofit and for-profit sectors. Using actuarial assumptions for defined benefit (DB) pension plans as a proxy for discretionary accounting choices, we examine whether nonprofit managers respond through their actuarial choices to incentives to manage DB pension assumptions, and whether differences exist in the aggressiveness of these assumptions for nonprofits and for-profits. We find evidence consistent with nonprofits managing pension assumptions when incentives and less monitoring exist. Comparing our nonprofits to a sample of for-profits, we find evidence consistent with nonprofits utilizing more aggressive pension assumptions and making stronger responses to incentives to manage these assumptions. Our findings are consistent with the premise that n...
The Administrators of Democracy: A Research Note on Local Election Officials

Local election offi cials are the administrators of democracy, but we know little about their views. Th is paper draws from two national surveys of local election offi cials. Th e authors fi nd that local election offi cials generally support the goals of the federal Help America Vote Act but are less enthusiastic about the actual impact of the legislation. Implementation theory helps explain their evaluation of federal reforms. Goal congruence with reform mandates, resource availability, and a willingness to accept federal involvement predicts support for these reforms. Federal policy changes have promoted electronic systems, and some of the authors’ fi ndings are relevant to research on e-government. Users of electronic voting machines tend to have high confi dence in them despite the signifi cant criticism the machines have faced. Local election offi cials who support e-government generally are more likely to more positively evaluate federal reforms.
Lower Bounds for Oblivious Subspace Embeddings

An oblivious subspace embedding (OSE) for some e,δ ∈ (0,1/3) and d ≤ m ≤ n is a distribution \(\mathcal{D}\) over ℝ m×n such that $$\Pr_{\Pi\sim\mathcal{D}}\left(\forall x\in W,\ (1-\varepsilon )\|x\|_2\le \|\Pi x\|_2 \le (1+\varepsilon )\|x\|_2 \right) \ge 1 - \delta $$ for any linear subspace W ⊂ ℝ n of dimension d. We prove any OSE with δ < 1/3 has m = Ω((d + log(1/δ))/e 2), which is optimal. Furthermore, if every Π in the support of \(\mathcal{D}\) is sparse, having at most s non-zero entries per column, we show tradeoff lower bounds between m and s.
Substituent Effect on the Formation and Reactivity of Platinum Carbenoids

A propargylic ester containing a propargylic alkoxy group has been observed to preferentially undergo [1,2]-acyl shift over [1,3]-shift. In addition, the complementary and contrasting reactivity of vinyl vs. alkynyl platinum carbenoids has been discovered. Vinyl platinum carbenoids are more prone to undergo [1,2]-H shift over addition to π-bonds whereas alkynyl platinum carbenoids preferentially add to π-bonds.
Agricultural Development for Peace

Agricultural development can contribute significantly to peace by raising incomes and employment, thereby reducing the social frustrations that give rise to violence. Agricultural growth also generates revenues for governments, allowing them to redress the grievances of disadvantaged populations. In this way, growth can be made more equitable, an effect that is enhanced if inequalities in access to natural capital, especially to land, are addressed as well. Agriculture is critical for countries rebuilding from war, especially in making recovery work for the poor. And by raising per capita incomes, agricultural development underpins new democracies. Agricultural development thereby supports political strategies for peace-building and democratization.