cssi/SciSciGPT-SciSciNet huggingface dataset:
Astrophysical bounds on the masses of axions and Higgs particles

Lower bounds on the mass of a light scalar (Higgs) or pseudoscalar (axion) particle are found in three ways: (1) by requiring that their effect on primordial nucleosynthesis not yield a deuterium abundance outside present experimental limits, (2) by requiring that the photons from their decay thermalize and not distort the microwave background, and (3) by requiring that their emission from helium-burning stars (red giants) not disrupt stellar evolution. The best bound is from (3); it requires the axion or Higgs-particle mass to be greater than about 0.2 MeV.
Representations of graphs modulo n

Abstract A graph is said to be representable modulo n if its vertices can be labelled with distinct integers between 0 and n−1 inclusive such that two vertices are adjacent if and only if the difference of their labels is relatively prime to n . The representation number of graph G is the smallest n such that G has a representation modulo n . We relate the representation number to the product dimension of a graph and use this connection to obtain new results for each case. We also obtain directly new results on representation numbers for several classes of graphs. In particular, we relate the representation number of the disjoint union of complete graphs to the existence of complete families of mutually orthogonal Latin squares.
A high resolution data-adaptive time-frequency representation

A data-adaptive time-frequency representation is developed that overcomes some limitations of the short-time Fourier transform, while avoiding the cross-terms that make the Wigner distribution and other bilinear representations difficult to interpret. The adaptive time-frequency representations uses Gaussian basis functions but varies their time width and chirp rate with time and frequency to achieve high signal concentration everywhere. A measure of local signal concentration allows fully automated determination of the optimal basis parameters. The adaptive method is computationally expensive, but may provide much better performance than any currently known technique. >
Do Masculine Names Help Female Lawyers Become Judges? Evidence from South Carolina

This paper provides the first empirical test of the Portia Hypothesis: Females with masculine monikers are more successful in legal careers. Utilizing South Carolina microdata, we look for correlation between an individual's advancement to a judgeship and his/her name's masculinity, which we construct from the joint empirical distribution of names and gender in the state's entire population of registered voters. We find robust evidence that nominally masculine females are favored over other females. Hence, our results support the Portia Hypothesis.
Power calculations for high flow CO electric discharge laser systems

A self-consistent model for high-flow electric discharge CO laser systems with coincident optical and flow axes is presented. The model employed couples the kinetics of the electrons and heavy particles with the optical and fluid dynamic processes in the laser system. The resulting integrodifferential system of equations governing this multilevel system was solved by an exact numerical scheme. The effects of composition, total mass flow rate and inlet pressure and temperature on the intensities, and total power output were investigated. The results indicate that, for a given input power and N/sub 2/ fraction, the efficiency increases by reducing the inlet temperature and increasing the velocity and/or the fraction of CO. Moreover, transitions on the lower vibrational bands can be obtained at the expense of lower efficiencies by reducing the CO fraction.
The representation of visual salience in monkey parietal cortex

When natural scenes are viewed, a multitude of objects that are stable in their environments are brought in and out of view by eye movements. The posterior parietal cortex is crucial for the analysis of space, visual attention and movement. Neurons in one of its subdivisions, the lateral intraparietal area (LIP), have visual responses to stimuli appearing abruptly at particular retinal locations (their receptive fields). We have tested the responses of LIP neurons to stimuli that entered their receptive field by saccades. Neurons had little or no response to stimuli brought into their receptive field by saccades, unless the stimuli were behaviourally significant. We established behavioural significance in two ways: either by making a stable stimulus task-relevant, or by taking advantage of the attentional attraction of an abruptly appearing stimulus. Our results show that under ordinary circumstances the entire visual world is only weakly represented in LIP. The visual representation in LIP is sparse, with only the most salient or behaviourally relevant objects being strongly represented.
Information Retrieval in Medicine: The SAPHIRE Experience

Information retrieval systems are being used increasingly in biomedical settings, but many problems still exist in indexing, retrieval, and evaluation. The SAPHIRE Project was undertaken to seek solutions for these problems. This article summarizes the evaluation studies that have been done with SAPHIRE, highlighting the lessons learned and laying out the challenges ahead to all medical information retrieval efforts. © 1995 John Wiley & Sons, Inc.
Reputation, Renegotiation, and the Choice between Bank Loans and Publicly Traded Debt

We model firms’ choice between bank loans and publicly traded debt, allowing for debt renegotiation in the event of financial distress. Entrepreneurs, with private information about their probability of financial distress, borrow from banks (multiperiod players) or issue bonds to implement projects. If a firm is in financial distress, lenders devote a certain amount of resources (unobservable to entrepreneurs ) to evaluate whether to liquidate the firm or to renegotiate its debt. We demonstrate that banks’ desire to acquire a reputation for making the “right” renegotiation versus liquidation decision provides them an endogenous incentive to devote a larger amount of resources than bondholders toward such evaluations. In equilibrium, bank loans dominate bonds from the point of view of minimixing inefficient liquidation; however, firms with a lower probability of financial distress choose bonds over bank loans.
Reflectivities of uniform and broken layered clouds

1 km AVHRR imagery data from the NOAA satellites, collected during the FIRE Marine Stratocumulus Intensive Field Observations, were used to determine differences between the reflectivities of uniform, layered clouds and those of broken clouds taken from the same layers. Observations for the 0.63 µ m channel indicated that regardless of the viewing geometry obtained with the polar orbiters, the average reflectivities of broken clouds were approximately 80–85% of the reflectivities of the same clouds when they formed uniform layers. Furthermore, the anisotropy of radiation reflected by uniform clouds appeared to be no different than that reflected by the broken clouds. Consequently, if the uniform, layered clouds observed in this study reflect according to plane-parallel theory, then the reflectivities of broken clouds could be approximated by simply reducing the values obtained with plane-parallel theory. For observations in the 3.7 µ m channel, the average reflectivities of the broken clouds were generally larger than the reflectivities of the uniform, layered clouds. Furthermore, the anisotropy of radiation reflected by broken clouds differed from that of the radiation reflected by uniform clouds. The reduced reflectivity at visible wavelengths for broken clouds may explain the 10% discrepancy between pre-satellite era estimates of the earth's albedo and satellite estimates. Furthermore, while the differences in reflectivities between uniform and broken clouds are qualitatively consistent with Monte Carlo simulations of finite cloud effects, they are also consistent with plane-parallel radiative transfer models in which the central portions of clouds contain relatively large concentrations of liquid water distributed among relatively large droplets, while the edges of clouds contain relatively low concentrations of liquid water distributed among relatively small droplets. DOI: 10.1034/j.1600-0889.1991.t01-3-00008.x
Realistic non-linear model and field quality analysis in RHIC interaction regions

The existence of multipole components in the dipole and quadrupole magnets is one of the factors limiting the beam stability in the RHIC operations. So, a realistic nonlinear model is crucial for understanding the beam behavior and to achieve the ultimate performance in RHIC. A procedure is developed to build a non-linear model using the available multipole component data obtained from measurements of RHIC magnets. We first discuss the measurements performed at different stages of manufacturing of the magnets in relation to their current state in RHIC. We then describe the procedure to implement these measurement data into tracking models, including the implementation of the multipole feed down effect due to the beam orbit offset from the magnet center. Finally, the field quality analysis in the RHIC interaction regions (IR) is presented.
Location-aided routing (LAR) in mobile ad hoc networks

A mobile ad hoc network consists of wireless hosts that may move often. Movement of hosts results in a change in routes, requiring some mechanism for determining new routes. Several routing protocols have already been proposed for ad hoc networks. This paper suggests an approach to utilize location information (for instance, obtained using the global positioning system) to improve performance of routing protocols for ad hoc networks. By using location information, the proposed Location‐Aided Routing (LAR) protocols limit the search for a new route to a smaller “request zone” of the ad hoc network. This results in a significant reduction in the number of routing messages. We present two algorithms to determine the request zone, and also suggest potential optimizations to our algorithms.
Tariff Equivalent of Technical Barriers to Trade with Imperfect Substitution and Trade Costs

The price-wedge method yields a tariff-equivalent estimate of technical barriers to trade (TBT). An extension of this method accounts for imperfect substitution between domestic and imported goods and incorporates recent findings on trade costs. We explore the sensitivity of this revamped TBT estimate to its key determinants (substitution elasticity, preference for home good, and trade cost). We use the augmented approach to investigate the recent Japan–U.S. apple trade dispute and find that removing the Japanese TBT would yield limited export gains to the United States. We then draw policy implications of our findings.
Terminal, Anionic Carbide, Nitride, and Phosphide Transition‐Metal Complexes as Synthetic Entries to Low‐Coordinate Phosphorus Derivatives

Anionic terminal one-atom nitride, phosphide, and carbide complexes are excellent starting materials for the synthesis of ligands containing low-coordinate phosphorus centers in the protecting coordination sphere of the metal complex. Salt-elimination reactions with chlorophosphanes lead to phosphaisocyanide, iminophosphinimide, and diorganophosphanylphosphinidene complexes in which the unusual phosphorus ligands are stabilized by coordination. X-ray structure analyses and density-functional calculations illuminate the bonding in these compounds.
The eyeball ROV: Design and control of a spherical underwater vehicle steered by an internal eccentric mass

A Remotely Operated Vehicle (ROV) is developed for use in the inspection of underwater structures in hazardous environments. The vehicle presented can change orientation like an eyeball using a novel gimbal mechanism for moving an internal eccentric mass. Combined with a pair of thrusters, the Eyeball ROV can move in any direction with non-holonomic constraints. In this paper the design concept is presented first, followed by dynamic and hydrodynamic analysis. Due to poor open loop stability characteristics, stability augmentation is implemented using onboard sensors and was designed and tested in simulation. A physical proof-of-concept prototype is also presented.
Wear Mechanisms in Electron Sources for Ion Propulsion, 2: Discharge Hollow Cathode

The wear of the keeper electrode in discharge hollow cathodes is a major impediment to the implementation of ion propulsion onboard long-duration space science missions. The development of a predictive theoretical model for hollow cathode keeper life has long been sought, but its realization has been hindered by the complexities associated with the physics of the partially ionized gas and the associated erosion mechanisms in these devices. Thus, although several wear mechanisms have been hypothesized, a quantitative explanation of life test erosion profiles has remained incomplete. A two-dimensional model of the partially ionized gas in a discharge cathode has been developed and applied to understand the mechanisms that drove the erosion of the keeper in two long-duration life tests of a 30-cm ion thruster. An extensive set of comparisons between predictions by the numerical simulations and measurements of the plasma properties and of the erosion patterns is presented. It is found that the near-plume plasma oscillations, predicted by theory and observed by experiment, effectively enhance the resistivity of the plasma as well as the energy of ions striking the keeper.
Instrumental variables methods in experimental criminological research: what, why and how

Quantitative criminology focuses on straightforward causal questions that are ideally addressed with randomized experiments. In practice, however, traditional randomized trials are difficult to implement in the untidy world of criminal justice. Even when randomized trials are implemented, not everyone is treated as intended and some control subjects may obtain experimental services. Treatments may also be more complicated than a simple yes/no coding can capture. This paper argues that the instrumental variables methods (IV) used by economists to solve omitted variables bias problems in observational studies also solve the major statistical problems that arise in imperfect criminological experiments. In general, IV methods estimate causal effects on subjects who comply with a randomly assigned treatment. The use of IV in criminology is illustrated through a re-analysis of the Minneapolis domestic violence experiment. The results point to substantial selection bias in estimates using treatment delivered as the causal variable, and IV estimation generates deterrent effects of arrest that are about one-third larger than the corresponding intention-to-treat effects.
Commentary: Cultural Stereotypes Can and Do Die: It's Time to Move on With Transracial Adoption

This commentary argues that the Multiethnic Placement Act, designed to combat common cultural stereotypes, provides clear guidance to state child welfare agencies and the mental health professionals that serve them, eliminating any regular consideration of race in the foster and adoptive placement of children. Given recent enforcement action by the U.S. Department of Health and Human Services, those who ignore this guidance act at peril of subjecting state agencies to the significant financial penalties mandated for any violation of the law.
MicrobesOnline: an integrated portal for comparative and functional genomics

Since 2003, MicrobesOnline (http://www.microbesonline.org) has been providing a community resource for comparative and functional genome analysis. The portal includes over 1000 complete genomes of bacteria, archaea and fungi and thousands of expression microarrays from diverse organisms ranging from model organisms such as Escherichia coli and Saccharomyces cerevisiae to environmental microbes such as Desulfovibrio vulgaris and Shewanella oneidensis. To assist in annotating genes and in reconstructing their evolutionary history, MicrobesOnline includes a comparative genome browser based on phylogenetic trees for every gene family as well as a species tree. To identify co-regulated genes, MicrobesOnline can search for genes based on their expression profile, and provides tools for identifying regulatory motifs and seeing if they are conserved. MicrobesOnline also includes fast phylogenetic profile searches, comparative views of metabolic pathways, operon predictions, a workbench for sequence analysis and integration with RegTransBase and other microbial genome resources. The next update of MicrobesOnline will contain significant new functionality, including comparative analysis of metagenomic sequence data. Programmatic access to the database, along with source code and documentation, is available at http://microbesonline.org/programmers.html.
Superconducting magnetic energy storage

Superconducting magnetic energy storage (SMES) is unique among the technologies proposed for diurnal energy storage for the electric utilities in that there is no conversion of the electrical energy, which is stored directly as a circulating current in a large superconducting magnet, into another energy form such as mechanical, thermal, or chemical. Thus one advantage of SMES is the inherent high storage efficiency that is possible because energy conversion processes are avoided. The actual round-trip efficiency of a large unit is expected to be 90 percent or greater. The fast response (< 100 ms) of the system to power demand means that a diurnal storage unit can also function as a swing generator or provide system stabilization. The major components of a SMES system are a large superconducting coil cooled by liquid helium, an ac-to-dc convertor, and a refrigerator that maintains the temperature of the helium coolant. This paper describes the design and functions of these and other components of an engineering reference design for a 1-GWh SMES unit. Also included is a sketch of the historical development of superconductivity, which was first discovered in 1911, and SMES, which was first proposed as a method of diurnal storage in 1969.
Gravitational collapse of k-essence

We perform numerical simulations of the gravitational collapse of a k-essence scalar field. When the field is sufficiently strongly gravitating, a black hole forms. However, the black hole has two horizons: a light horizon (the ordinary black hole horizon) and a sound horizon that traps k-essence. In certain cases the k-essence signals can travel faster than light and the sound horizon is inside the light horizon. Under those circumstances, k-essence signals can escape from the black hole. Eventually, the two horizons merge and the k-essence signals can no longer escape.
Functional interactions between tumor and peripheral nerve: changes in excitability and morphology of primary afferent fibers in a murine model of cancer pain

We used a murine model to investigate functional interactions between tumors and peripheral nerves that may contribute to pain associated with cancer. Implantation of fibrosarcoma cells in and around the calcaneus bone produced mechanical hyperalgesia of the ipsilateral paw. Electrophysiological recordings from primary afferent fibers in control and hyperalgesic mice with tumor revealed the development of spontaneous activity (0.2-3.4 Hz) in 34% of cutaneous C-fibers adjacent to the tumor (9-17 d after implantation). C-fibers in tumor-bearing mice exhibited a mean decrease in heat threshold of 3.5 +/− 0.10 °C. We also examined innervation of the skin overlying the tumor. Epidermal nerve fibers (ENFs) were immunostained for protein gene product 9.5, imaged using confocal microscopy, and analyzed in terms of number of fibers per millimeter of epidermal length and branching (number of nodes per fiber). Divergent morphological changes were linked to tumor progression. Although branching of ENFs increased significantly relative to control values, in later stages (16-24 d after implantation) of tumor growth a sharp decrease in the number of ENFs was observed. This decay of epidermal innervation of skin over the tumor coincided temporally with gradual loss of electrophysiological activity in tumor-bearing mice. The development of spontaneous activity and sensitization to heat in C-fibers and increased innervation of cutaneous structures within the first 2 weeks of tumor growth suggest activation and sensitization of a proportion of C-fibers. The decrease in the number of ENFs observed in later stages of tumor development implicates neuropathic involvement in this model of cancer pain.
One-Pot Synthesis of 1,4-Disubstituted 1,2,3-Triazoles from In Situ Generated Azides

[reaction: see text] 1,4-Disubstituted 1,2,3-triazoles are obtained in excellent yields by a convenient one-pot procedure from a variety of readily available aromatic and aliphatic halides without isolation of potentially unstable organic azide intermediates.
New α-methylene-γ-butyrolactones with antimycobacterial properties

Abstract The synthesis and antimycobacterial activity of a series of α-methylene-γ-butyrolactones based on the natural product protolichesterinic acid are described. Compounds 9 – 12 bearing an allylamide group at the C-4 position showed improved activity with MICs in the range of 6.25–12.5 μg/mL.
Improved upper bound for the redundancy of fix-free codes

A variable-length code is a fix-free code if no codeword is a prefix or a suffix of any other codeword. In a fix-free code, any finite sequence of codewords can be decoded in both directions, which can improve the robustness to channel noise and speed up the decoding process. In this paper, we prove a new sufficient condition of the existence of fix-free codes and improve the upper bound on the redundancy of optimal fix-free codes.
A comparison of application-level and router-assisted hierarchical schemes for reliable multicast

One approach to achieving scalability in reliable multicast is to use a hierarchy. A hierarchy can be established at the application level, or by using router-assist. With router-assist we have more fine-grain control over the placement of error-recovery functionality, therefore, a hierarchy produced by assistance from the routers is expected to have better performance. In this paper, we test this hypothesis by comparing two schemes, one that uses an application-level hierarchy (ALH) and another that uses router-assisted hierarchy (RAH). Contrary to our expectations, we find that the qualitative performance of ALH is comparable to RAH. We do not model the overhead of creating the hierarchy nor the cost of adding router-assist to the network. Therefore, our conclusions inform rather than close the debate of which approach is better.
A separator-analyzer flowmeter for complex liquids in microfluidic systems

The measurement and control of the flowrate of fluids containing charged macromolecular species and particles is required for a number of applications, such as controlled-drug-delivery and microscale bioreactors. The flowrates that need to be measured for such systems can be as small as microliters per day. We are developing a novel flowmeter, called the separator-analyzer flowmeter (SAF meter), to measure the flow rate of suspensions of charged macromolecules or particles. The SAF meter consists of a channel that splits into two parts and then recombines. A pair of electrodes is positioned before the channel bifurcation. When a DC potential is applied across this pair of electrodes, the charged species are dragged toward one electrode, and the solutions flowing into the two arms downstream differ in the concentration (separator). This difference is inversely proportional to the flowrate of the original mixture. The concentration difference can be measured optically or electrochemically (analyzer). Based on the input to the separator (strength of the applied electric field), and the output from the analyzer (concentrations in the two arms), we can obtain the flowrate of the solution. A milliscale prototype has been fabricated and has been used to measure flowrates from 25-75 /spl mu/l/min.
Approaching the Capacity of Wireless Networks through Distributed Interference Alignment

Recent results establish the optimality of interference alignment to approach the Shannon capacity of interference networks at high SNR. However, the extent to which interference can be aligned over a finite number of signalling dimensions remains unknown. Another important concern for interference alignment schemes is the requirement of global channel knowledge. In this work we provide examples of iterative algorithms that utilize the reciprocity of wireless networks to achieve interference alignment with only local channel knowledge at each node. These algorithms also provide numerical insights into the feasibility of interference alignment that are not yet available in theory.
Global satellite triangulation and trilateration results

The paper summarizes the results of the Ohio State University geometric adjustment for the coordinates at 158 satellite tracking stations. In the solution the origin of the coordinate system is defined through the ‘inner’ adjustment procedure, whereas the orientation is through the Conventional International Origin and the Greenwich Mean Astronomical Meridian, both as defined by the Bureau International de l'Heure. The scale is implemented through Secor observations and weighted height constraints. Chord distances derived from C band radar observations and from electronic distance measurements are also included, but they seem to have very little effect. The scale selected corresponds to a best fitting ellipsoid of a = 6,378,142 m and 1/ƒ = 298.25. The average standard deviation of a single coordinate is 3.9 m. Comparisons with external standards generally show good agreements: scale agreement with dynamic satellite solutions is 1:1,600,000 and with terrestrial surveys is 1:575,000; the root mean square residual of comparisons with geoid undulations from satellite surface gravimetric solutions is 6.1 m, with an average discrepancy of only −0.3 m. The paper also presents satisfactory transformation parameters for the NAD 1927, the Australian and the South American 1969 geodetic datums.
α,β-functionalization of enones via pentacovalent oxaphospholenes

Abstract 2,2,2-triethoxy-1,2λ5-oxaphospholene, 1, reacts under mild, neural conditions with bromine, dialkyl azodicarboxylates, and oxaziridines to produce β-heteroatom substituted γ-ketophosphonates and β-acyl vinyl phosphonate in high yields.
Communities of practice: performance and evolution

We present a detailed model of collaboration in communities of practice and we examine its dynamical consequences for the group as a whole. We establish the existence of a novel mechanism that allows the community to naturally adapt to growth, specialization, or changes in the environment without the need for central controls. This mechanism relies on the appearance of a dynamical instability that initates an exploration of novel interactions, eventually leading to higher performance for the community as a whole.
How Many Clusters? An Information-Theoretic Perspective

Clustering provides a common means of identifying structure in complex data, and there is renewed interest in clustering as a tool for the analysis of large data sets in many fields. A natural question is how many clusters are appropriate for the description of a given system. Traditional approaches to this problem are based on either a framework in which clusters of a particular shape are assumed as a model of the system or on a two-step procedure in which a clustering criterion determines the optimal assignments for a given number of clusters and a separate criterion measures the goodness of the classification to determine the number of clusters. In a statistical mechanics approach, clustering can be seen as a trade-off between energy- and entropy-like terms, with lower temperature driving the proliferation of clusters to provide a more detailed description of the data. For finite data sets, we expect that there is a limit to the meaningful structure that can be resolved and therefore a minimum temperature beyond which we will capture sampling noise. This suggests that correcting the clustering criterion for the bias that arises due to sampling errors will allow us to find a clustering solution at a temperature that is optimal in the sense that we capture maximal meaningful structure—without having to define an external criterion for the goodness or stability of the clustering. We show that in a general information-theoretic framework, the finite size of a data set determines an optimal temperature, and we introduce a method for finding the maximal number of clusters that can be resolved from the data in the hard clustering limit.
Regionalization of Local Public Health Systems in the Era of Preparedness

Post-9/11, preparedness planning has catalyzed intrastate regionalization of local public health resources throughout the United States. Investigating this trend unveils several regionalization themes, relevant in other sectors of government, which are applicable to local public health. In this review article, we begin by briefly examining the lessons learned from regionalization for police and fire services, drawing comparisons to public health. Then we provide a brief history of the accelerating regionalization of local public health services sparked by the current attention to emergency preparedness. In particular, we offer case studies from Massachusetts and the National Capital Region to highlight examples of regionalization outcomes related to networking, coordination, standardization, and centralization of public health services. The impact of social capital on preparedness is also explored. Finally, we summarize research needs for the future.
Wafer-Level Strength and Fracture Toughness Testing of Surface-Micromachined MEMS Devices

Determination of the mechanical properties of MEMS (microelectromechanical systems) materials is necessary for accurate device design and reliability prediction. This is most unambiguously performed using MEMS-fabricated test specimens and MEMS loading devices. We describe here a wafer-level technique for measuring the bend strength, fracture toughness, and tensile strength of MEMS materials. The bend strengths of surface-micromachined polysilicon, amorphous silicon, and polycrystalline 3C SiC are 5.1±1.0, 10.1±2.0, and 9.0±1.0 GPa, respectively. The fracture toughness of undoped and P-doped polysilicon is 1.2±0.2 MPa√m, and the tensile strength of polycrystalline 3C SiC is 3.2±1.2 GPa. These results include the first report of the mechanical strength of micromachined polycrystalline 3C SiC.
Modeling communicative behavior using permissions and obligations

In order to provide flexible control over agent communication, we propose an integrated approach that involves using positive and negative permissions and obligations to describe both conversation specifications and policies. Conversation specifications are described in terms of the speech acts that an agent can/cannot/must/must not perform based on the sequence of messages received and sent. On the other hand, conversation policies restrict how the specifications are used and are defined over the attributes of the sender, receiver, message content, and context in general. Other policies like management, social, privacy etc. are defined at a higher level of abstraction and restrict the general behavior of agents. Whenever they deal with communication, the higher level policies are translated into conversation policies using the syntax and semantics of the specific communication language being used. Agents use a policy engine for reasoning over conversation specifications and applicable policies in order to decide what communicative act to perform next. Our work is different from existing research in communication policies because it is not tightly coupled to any domain information such as mental states of agents or specific communicative acts.The main contributions of this work include (i) an extensible framework that can support varied domain knowledge and different agent communication languages, and (ii) the declarative representation of conversation specifications and policies in terms of permitted and obligated speech acts.
Financial leverage changes associated with corporate mergers

We empirically examine whether firms increase financial leverage following mergers. Firms could increase financial leverage either because of an increase in debt capacity or because of unused debt capacity from pre-merger years. We find that financial leverage of combined firms increases significantly following mergers. A cross-sectional analysis shows that the change in financial leverage around mergers is significantly positively correlated with the announcement period market-adjusted returns. Further tests indicate that the increase in financial leverage is an outcome of an increase in debt capacity, although there is weak evidence that some of the increase in financial leverage is a result of past unused debt capacity. q 2000 Elsevier Science B.V. All rights reserved.
Flying Beneath the Radar of Health Reform: The Community Living Assistance Services and Supports (CLASS) Act

The Patient Protection and Affordable Care Act attempts to address prevailing deficiencies in long-term care (LTC) financing through the Community Living Assistance Services and Supports (CLASS) Act, a national voluntary LTC insurance program administered by the Federal government. The CLASS Act is intended to supplement rather than supplant assistance received from other payers. Furthermore, its reliance on a cash benefit allocated by beneficiaries with the assistance of counseling services makes it consistent with the consumer-directed philosophy increasingly favored by the LTC advocacy community. Largely due to inadequate take-up, however, particularly among better than average risks, it is unlikely that implementation of the CLASS Act will fundamentally alter the current public-private partnership for LTC financing. Instead, voluntary enrollment combined with a lack of medical underwriting could lead to disproportionate numbers of high-cost enrollees. This could result in premium increases that further discourage participation on the part of the broader population. Barring making the program mandatory, there are a number of comparatively minor changes policymakers could make to strengthen the risk pool, though doing so will involve a trade-off between attracting better-off risks while eschewing those likely to need the benefit most. Thus, although the CLASS Act may provide a meaningful benefit for those who enroll, its impact on improving the affordability of LTC for most Americans will likely be limited. Most will continue to rely on substantial unpaid care, out-of-pocket payments when formal care is required, and Medicaid when all other money has run out.
Incumbent Entry into New Market Niches: The Role of Experience and Managerial Choice in the Creation of Dynamic Capabilities

Increasingly, technological innovation creates markets for new products and services. To survive, firms must respond to these new markets. How do firms develop the capabilities necessary to succeed in such changing conditions? Some suggest that experience with previous entry builds such capabilities. Others suggest that capabilities arise from experience producing and selling to existing markets. The role of managers is also debated. Some argue that experience with existing markets causes managers to miss entry opportunities. Others argue that managers enter new markets when their firm possesses the experience needed to compete effectively. In this paper, we explore these issues by investigating entry patterns in the disk-drive industry. We investigate the effect of experience in existing markets and experience with previous market entry. We find that experience in previous markets increased the probability that a firm would enter a new market. We show that this experience had greater value if the firm entered the new market. We infer that managers chose to enter these markets to obtain this increase in value.
Efficient Linkage Discovery by Limited Probing

This paper addresses the problem of discovering the structure of a fitness function from binary strings to the reals under the assumption of bounded epistasis. Two loci (string positions) are epistatically linked if the effect of changing the allele (value) at one locus depends on the allele at the other locus. Similarly, a group of loci are epistatically linked if the effect of changing the allele at one locus depends on the alleles at all other loci of the group. Under the assumption that the size of such groups of loci are bounded, and assuming that the function is given only as a "black box function", this paper presents and analyzes a randomized algorithm that finds the complete epistatic structure of the function in the form of the Walsh coefficients of the function.
Synthesis of nucleoside 3',5'-cyclic boranophosphorothioate, a new type of cyclic nucleotide.

The first examples of a borane-containing doubly P-modified chiral cyclic nucleoside monophosphate (cNMP), e.g., thymidine and 5-fluoro-2'-deoxyuridine 3',5'-cyclic boranophosphorothioates, have been synthesized; these cNMP analogues with increased lipophilicity could be potential anticancer prodrugs and useful probes for mechanistic studies.
Simplifying oligosaccharide synthesis: efficient synthesis of lactosamine and siaylated lactosamine oligosaccharide donors.

A practical sequence is described for converting d-glucosamine into peracetylated Gal(β-1,4)GlcNTroc(β1-S)Ph and Neu5Ac(α-2,3)Gal(β-1,4)GlcNTroc(β1-S)Ph building blocks using a synthetic strategy based on chemoenzymatic oligosaccharide synthesis. The known trichloroethoxycarbonyl, N-Troc, protecting group was selected as a suitable protecting group for both enzymatic and chemical reaction conditions. These oligosaccharide building blocks proved effective donors for the β-selective glycosylation of the unreactive OH-3 of a polymeric PEG-bound acceptor and for the axial OH-2 of a mannose acceptor in good yields. The resulting complex oligosaccharides are useful for vaccine and pharmaceutical applications.
Laser damage of calcium fluoride by ArF excimer laser irradiation

Artificially grown excimer grade calcium fluoride is one of key optical materials used in microlithography applications. Such calcium fluoride is required for optical components requiring high laser durability and laser induced bulk damage threshold (LIDT). The mechanical properties of calcium fluoride can vary depending on the crystal axis, , and . For example, material hardness is highest in the {100} crystal orientation. Furthermore, it is also known to cleave in the {111} plane. Therefore there is a possibility of a property that originates in such a crystal structure that influences LIDT. In this study, we investigated the relationship between crystal structure, laser durability and LIDT. The influence in the relation between the polarization plane of the ArF excimer laser and the crystal orientation of calcium fluoride in regards to LIDT was examined. The samples were all prepared from the same CaF2 crystal with optical axis's of , and . The azimuth of the samples was measured by the reflection Laue method. For the experiment, the samples were rotated to the polarization plane of the ArF excimer laser, and the change in the number of irradiation pulses that damage was observed and measured. As a result, we determined the position of the crystal orientation of the calcium fluoride relative to the polarization plane of the ArF excimer laser that produced the highest LIDT.
Synthesis of 3-Iodoindoles by the Pd/Cu-Catalyzed Coupling of N,N-Dialkyl-2-iodoanilines and Terminal Acetylenes, Followed by Electrophilic Cyclization

3-Iodoindoles have been prepared in excellent yields by coupling terminal acetylenes with N,N-dialkyl-o-iodoanilines in the presence of a Pd/Cu catalyst, followed by an electrophilic cyclization of the resulting N,N-dialkyl-o-(1-alkynyl)anilines using I2 in CH2Cl2. Aryl-, vinylic-, alkyl-, and silyl-substituted terminal acetylenes undergo this process to produce excellent yields of 3-iodoindoles. The reactivity of the carbon−nitrogen bond cleavage during cyclization follows the following order: Me > n-Bu, Me > Ph, and cyclohexyl > Me. Subsequent palladium-catalyzed Sonogashira, Suzuki, and Heck reactions of the resulting 3-iodoindoles proceed smoothly in good yields.
T-duality constraints on higher derivatives revisited

We ask to what extent are the higher-derivative corrections of string theory constrained by T-duality. The seminal early work by Meissner tests T-duality by reduction to one dimension using a distinguished choice of field variables in which the bosonic string action takes a Gauss-Bonnet-type form. By analyzing all field redefinitions that may or may not be duality covariant and may or may not be gauge covariant we extend the procedure to test T-duality starting from an action expressed in arbitrary field variables. We illustrate the method by showing that it determines uniquely the first-order α′ corrections of the bosonic string, up to terms that vanish in one dimension. We also use the method to glean information about the $$ \mathcal{O}\left({\alpha}^{\prime 2}\right) $$ corrections in the double field theory with Green-Schwarz deformation.
PRICING LEGAL OPTIONS: A BEHAVIORAL PERSPECTIVE

Many legal rules can be interpreted as creating options. Option pricing is thus important for understanding the ex ante effects of these rules. And, recognizing that individuals, whose behavior the law aims to influence, are imperfectly rational, a behavioral option pricing model is a potentially helpful tool for legal policy. This paper develops such a model and applies it to a series of legal problems in tort law, contract law, corporate law and criminal law.
Windows into relational events: data structures for contiguous subsequences of edges

We consider the problem of analyzing social network data sets in which the edges of the network have timestamps, and we wish to analyze the subgraphs formed from edges in contiguous subintervals of these timestamps. We provide data structures for these problems that use near-linear preprocessing time, linear space, and sublogarithmic query time to handle queries that ask for the number of connected components, number of components that contain cycles, number of vertices whose degree equals or is at most some predetermined value, number of vertices that can be reached from a starting set of vertices by time-increasing paths, and related queries.
Crowdsourced geometric morphometrics enable rapid large-scale collection and analysis of phenotypic data

Summary Advances in genomics and informatics have enabled the production of large phylogenetic trees. However, the ability to collect large phenotypic data sets has not kept pace. Here, we present a method to quickly and accurately gather morphometric data using crowdsourced image-based landmarking. We find that crowdsourced workers perform similarly to experienced morphologists on the same digitization tasks. We also demonstrate the speed and accuracy of our method on seven families of ray-finned fishes (Actinopterygii). Crowdsourcing will enable the collection of morphological data across vast radiations of organisms and can facilitate richer inference on the macroevolutionary processes that shape phenotypic diversity across the tree of life.
Determination of Sulfur in Rubber Vulcanizates

Abstract A combustion method for rubber which determines the sulfur evolved at 480° to 500° C is compared with the fusion and the zinc-nitric acid methods. In the combustion method an interaction occurs between sulfur and fillers present in the rubber. The effect of particular fillers with respect to this interaction is discussed. A value representative of the organically bound sulfur in an extracted specimen can be obtained by the combustion method when no reaction takes place between the sulfur and the fillers during combustion. The fusion method yields results in good agreement with the total sulfur added in compounding the rubber samples. Except in the presence of barium compounds, the zinc-nitric acid method likewise determines total sulfur. When barium compounds are present, barium sulfate is formed during the oxidation, and low values are obtained for the total sulfur.
Hard Probes: After the dust has settled!

Abstract A lot has been learnt in the 15 years since the first data on jet modification at the Relativistic Heavy Ion Collider (RHIC). This proceeding will describe the portion of the theory that is unassailable, and attempt to chart a course for the next period of precision measurements and related calculations. In particular, we will focus on the emerging series of higher order calculations, which may reveal the scale, energy and temperature dependence of jet transport coefficients, as well as develop ingredients for a future NLO calculation of jet modification. Connections with the underlying degrees of freedom in the Quark Gluon Plasma (QGP) will be explored. We will discuss the challenges faced by Monte-Carlo event generators and their comparison with a broad spectrum of jet modification data. First principles calculations of transport coefficients, and the determination of new transport coefficients which encapsulate the transition of energy momentum from the jet scale to the medium scale will also be discussed.
ORIF FOR DISPLACED FEMORAL NECK FX'S IN THE <60 ACTIVE PATIENT – AFFIRMS

Few will disagree that the best femoral head that a young patient can have is his or her own, native femoral head. In the active, healthy patient under age 60 with a displaced femoral neck fracture, well-done, timely ORIF presents the best chance of preserving the patient9s native femoral head. Arthroplasty is generally reserved for older patients, over age 60, where attempts at ORIF in this setting have demonstrated failure rates over 40%. Recent studies have documented that approximately 80% of young patients with displaced femoral neck fractures treated with ORIF will keep their own femoral head for 10 years after injury. The variables under the surgeon9s control include timing of fixation, quality of reduction, accurate implant placement and implant selection, and capsulotomy. All of these variables potentially affect outcomes. Fractures in this young age group are frequently high shear angle (vertical) Pauwels type 3 fractures, and benefit from fixed angle fixation. The author prefers anatomic reduction and stabilization with a sliding hip screw and a superiorly placed derotation screw. Careful attention to detail is important to obtain an anatomic reduction, which is the most important variable in the outcome of these challenging injuries.
Indistinguishability Obfuscation: From Approximate to Exact

We show general transformations from subexponentially-secure approximate indistinguishability obfuscation IO where the obfuscated circuit agrees with the original circuit on a $$1/2+\epsilon $$ fraction of inputs on a certain samplable distribution, into exact indistinguishability obfuscation where the obfuscated circuit and the original circuit agree on all inputs. As a step towards our results, which is of independent interest, we also obtain an approximate-to-exact transformation for functional encryption. At the core of our techniques is a method for "fooling" the obfuscator into giving us the correct answer, while preserving the indistinguishability-based security. This is achieved based on various types of secure computation protocols that can be obtained from different standard assumptions. Put together with the recent results of Canetti, Kalai and Paneth TCC 2015, Pass and Shelat TCC 2016, and Mahmoody, Mohammed and Nemathaji TCC 2016, we show how to convert indistinguishability obfuscation schemes in various ideal models into exact obfuscation schemes in the plain model.