cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluating Statistical Models of Mortgage Lending Discrimination: A Bank-Specific Analysis

The B oston Fed' s study on mor tgage lending discrimination has prompted a considerable rise in the use of statistical methods to evaluate banks' lending behavior. However, several is sues c oncerning th e validity, accuracy, and reliability of statistical mo dels r emain unresolved. In this paper, we attempt to address several of those issues within the context of a bank-specific analysis. Using data gathered from three nationally chartered banks, we extend the "standard" model outlined in the Boston Fed study. We conclude that a model specification that incorporates the specific underwriting guidelines of the individual bank is more appropriate than a broadly-defined, generic specification applied across all banks. We also show that the process of incorporating the bank-specific guidelines is itself difficult and can be complicated further by the lack of accurate data upon which to build a valid representative sample. We discuss several additional methodological issues concerning model validity, specification, sample design, and data accuracy th at mu st b e addressed if a statistical a pproach is to become a useful a nd accurate supervisory tool.
Simple Analytics of the Government Expenditure Multiplier

This paper explains the key factors that determine the output multiplier of government purchases in New Keynesian models, through a series of simple examples that can be solved analytically. Sticky prices or wages allow for larger multipliers than in a neoclassical model, though the size of the multiplier depends crucially on the monetary policy response. A multiplier well in excess of 1 is possible when monetary policy is constrained by the zero lower bound, and in this case welfare increases if government purchases expand to partially flll the output gap that arises from the inability to lower interest rates.
Rational design and synthesis of novel nucleotide anti-Giardia agents

Design and synthesis of a novel nucleotide anti-Giardia agent that is micromolar inhibitor of Giardia trophozoite growth in culture is described.
Sleeping beauty reconsidered: conditioning and reflection in asynchronous systems

A careful analysis of conditioning in the Sleeping Beauty problem is done, using the formal model for reasoning about knowledge and probability developed by Halpern and Tuttle. While the Sleeping Beauty problem has been viewed as revealing problems with conditioning in the presence of imperfect recall, the analysis done here reveals that the problems are not so much due to imperfect recall as to asynchrony. The implications of this analysis for van Fraassen's Reflection Principle and Savage's Sure-Thing Principle are considered.
El Estado y el ciudadano

This paper examines the institutional mechanisms through which rigths of all citizens can be protected in democracies. "llorizontal" mechanisms consist of mutual checks and balances among difibrent branches of govern-ment. "Vertical" mechanisms are those through which citizens exercise their control over the government. One vertical mechanism are the elections. But elections are a blunt instrument and additional mechanisms are necessary to enable popular control. Yet these mechanisms may accentuate political in-equality, rather than reduce it. The alternative hypothesis is that unequal protection of rights is due not to the internal structure of the state but to the social and economic conditions which it confronts. Perhaps in a highly unequal society, no state institutions can enforce the law universally, regardless how well the horizontal and the vertical mechanisms are designed. Thus reform of the state, while necessary, may be insufficient to overcome political inequality in the face of economic and social inequality.
Three-Dimensional Numerical Simulation of Circulation and Heat Transfer in an Electrically Boosted Glass Melting Tank

A three-dimensional numerical methodology to simulate the effect of electric boosting on glassmelt circulation and heat transfer in a glass melting furnace is presented. Due to a small, characteristic Hartmann number, the ponderomotive forces in the momentum equation were neglected. The voltage and electric current fields within the melt were determined by solving real and imaginary parts of the electric potential. The Joulean heat dissipation was determined and coupled to the energy equation of the melt. Other relevant processes, such as batch-melting and heat transfer from combustion space, were integrated into a system model. Merits of electric boosting were examined by obtaining some representative results and comparing model predictions with and without electric boosting.
Search for the electric dipole moment of the electron with thorium monoxide

The electric dipole moment of the electron (eEDM) is a signature of CP-violating physics beyond the standard model. We describe an ongoing experiment to measure or set improved limits to the eEDM, using a cold beam of thorium monoxide (ThO) molecules. The metastable H 3 � 1 state in ThO has important advantages for such an experiment. We argue that the statistical uncertainty of an eEDM measurement could be improved by as much as three orders of magnitude compared to the current experimental limit, in a first-generation apparatus using a cold ThO beam. We describe our measurements of the H state lifetime and the production of ThO molecules in a beam, which provide crucial data for the eEDM sensitivity estimate. ThO also has ideal properties for the rejection of a number of known systematic errors; these properties and their implications are described. (Some figures in this article are in colour only in the electronic version)
Prices, Incentives, and Economic Growth

This paper examines the economic effects of government directives and interventions in developed, developing and socialist countries that create distortions in the system of incentives. The discussion concerns policy-imposed distortions rather than endogenous distortions, which find their origin in market imperfections. Government measures designed to correct market imperfections fall outside the scope of this paper. Consideration is given to policy-imposed distortions in product and factor markets, and the effects of these distortions on the efficiency of resource allocation and economic growth that have been often neglected in the past. In so doing, use is made of empirical evidence that has accumulated in recent years.
Labor Market Policies and IMF Advice in Advanced Economies during the Great Recession

In this paper we present and analyze the IMF’s labor market recommendations for advanced economies since the beginning of the crisis, both in general and specifically in program countries. Our analysis is informed by our reading of the theoretical and empirical literature on the design of labor market policies and institutions in advanced economies. We organize our discussion around two concepts: micro flexibility, namely the ability of the economy to allow for the reallocation of workers to jobs needed to sustain growth; and macro flexibility, namely the ability of the economy to adjust to macroeconomic shocks. Achieving both types of flexibility while protecting workers and maintaining incentives for workers and firms to invest in existing relations, is not that simple, and the design of labor market institutions faces delicate trade-offs. E2, J3, J5, J6
Particle Based Plasma Simulation for an Ion Engine Discharge Chamber

A particle-based model with a Monte Carlo collision model has been developed to study the plasma inside the discharge chamber of an ion engine. This model tracks five major particle types inside the discharge chamber in detail: xenon neutrals, singly charged xenon ions, doubly charged xenon ions, secondary electrons, and primary electrons. Both electric and magnetic field effects are included in the calculation of the charged particle's motion. The electric fields inside the discharge chamber are computed using a new approach. Also, detailed particle collision mechanisms are enabled. Validation of this computational model has been made on NASA's three-ring Solar Electric Propulsion Technology Application Readiness Program discharge chamber, at the 2.29 kW input power, 1.76 A beam current, and 1100 V beam voltage operating condition. Comparisons of numerical simulation results with experimental measurements are found to have good agreement. The computed ion beam current differs from experiments by 1% and the computed discharge current differs from experiments by 22%. The plasma ion production cost compares within 7% and the beam ion production cost compares within 16% of the experimental values. The overall computed thruster efficiency is found to differ from experiments by 11 %. In addition, steady-state results are given for particle number density distributions, kinetic energy, particle energy loss mechanisms, and current density collected at the chamber walls.
Neogene Siwalik mammalian lineages: Species longevities, rates of change, and modes of speciation

Abstract A long depositional sequence from northern Pakistan provides a good fossil record of terrestrial vertebrates for the interval of 18-7 Ma. Making allowances for possible range extensions, we use this record as a direct measure of species longevities. There is a correlation between body size and longevity, smaller mammals frequently being short-lived and larger taxa showing durations up to ca. 10 m.y. The distribution of small mammal longevities indicates an exponential decrease in frequency from a high modal value in the smallest increment measured (0–200,000 yrs). The most frequent value for large mammals is also the smallest increment measured (1 m.y.), but that distribution may not be unimodal. Small mammal taxa of short duration are concentrated late in the sequence, after 9 Ma especially. The middle Miocene fauna is more stable, with species showing longer durations. The contrast in longevities corresponds with hypothesized greater environmental stability in the middle Miocene. For comparison, the Paleogene sequence of Wyoming indicates short median species durations, with few surveyed taxa lasting over 2 m.y. Siwalik mammals show diverse modes of evolution, but stasis in at least some features is usual, with species boundaries corresponding to morphological breaks. Up to half of the Siwalik rodent and artiodactyl species surveyed likely immigrated from outside the biogeographic province, and for a few, historical data are sufficient to stipulate when and by what route they came to the Indian subcontinent.
Correlated Gaussian hyperspherical method for few-body systems

We develop a numerical technique to describe few-body systems. Correlated Gaussian basis functions are used to expand the channel functions in the hyperspherical representation. The method is proven to be robust and efficient compared to other numerical techniques. The method is applied to few-body systems with short-range interactions, including several examples for three- and four-body systems. Specifically, for the two-component, four-fermion system, we extract the coefficients that characterize its behavior at unitarity.
Improving health service delivery in developing countries : from evidence to action

Decision makers and the public are in need of information to guide their decisions about how to strengthen health services. This book pulls together available evidence concerning strategies to improve health services delivery in low- and middle-income countries (LMICs), using current methods to assemble a knowledge base and analyze the findings. It describes the results of reviews of such strategies, and how such strategies can produce gains for the poor. This type of information is intended to help decision makers in LMICs learn from others and from their own experiences, so that they may develop and implement strategies that will improve health services in their own setting. The book provides some suggestions for what works and how to improve implementation, as the evidence does not hold up for 'blueprint' planning. It finds that there are many ways that can succeed in improving health services. But not nearly enough attention has been paid to demonstrating how to improve services for the poor. Approaches that ask difficult questions, use information intelligently, and involve key stakeholders and institutions are critical to 'learning and doing' practices that underlie successful implementation of health services.
Multiple Access Outerbounds and the Inseparability of Parallel Interference Channels

It is known that the capacity of parallel (multi-carrier) Gaussian point-to-point, multiple access and broadcast channels can be achieved by separate encoding for each subchannel (carrier) subject to a power allocation across carriers. In this paper we show that such a separation does not apply to parallel Gaussian interference channels in general. A counter-example is provided in the form of a 3 user interference channel where separate encoding can only achieve a sum capacity of log(SNR) +o(log(SNR)) per carrier while the actual capacity, achieved only by joint-encoding across carriers, is 3/2(log(SNR))+o(log(SNR)) per carrier. As a byproduct of our analysis, we propose a class of multiple-access-outerbounds on the capacity of the 3 user interference channel.
A new hematite formation mechanism for Mars

The origin of hematite detected in Martian surface materials is commonly attributed to weathering processes or aqueous precipitation. Here, we present a new hematite formation mechanism that requires neither water nor weathering. Glass-rich basalts with Martian meteorite-like chemistry (high FeO, low Al2O3) oxidized at high (700 and 900 °C) temperatures in air and CO2, respectively, form thin (<1 μm) hematite coatings on their outermost surfaces. Hematite is manifested macroscopically by development of magnetism and a gray, metallic sheen on the glass surface and microscopically by Fe enrichment at the glass surface observed in element maps. Visible and nearinfrared, thermal infrared, and Raman spectroscopy confirm that the Fe enrichment at the oxidized glass surfaces corresponds to hematite mineralization. Hematite formation on basaltic glass is enabled by a mechanism that induces migration of Fe2+ to the surface of an oxidizing glass and subsequent oxidation to form hematite. A natural example of the hematite formation mechanism is provided by a Hawaiian basalt hosting a gray, metallic sheen that corresponds to a thin hematite coating. Hematite coating development on the Hawaiian basalt demonstrates that Martian meteorite-like FeO contents are not required for hematite coating formation on basalt glass and that such coatings form during initial extrusion of the glassy basalt flows. If gray hematite originating as coatings on glassy basalt flows is an important source of Martian hematite, which is feasible given the predominance of igneous features on Mars, then the requirement of water as an agent of hematite formation is eliminated.
Convenient Preparation of a Novel Class of Imidazo[1,5-a]pyridines: Decisive Role by Ammonium Acetate in Chemoselectivity

A facile and one-pot straightforward methodology has been developed to prepare a novel class of imidazo[1,5-a]pyridines. A key role played by ammonium acetate in chemoselectivity has been examined.
Graph theoretic software watermarks: implementation, analysis, and attacks

This paper presents an implementation of the novel watermarking method proposed by Venkatesan, Vazirani, and Sinha in their recent paper A Graph Theoretic Approach to Software Watermarking. An executable program is marked by the addition of code for which the topology of the control-flow graph encodes a watermark. We discuss issues that were identified during construction of an actual implementation that operates on Java bytecode. We measure the size and time overhead of watermarking, and evaluate the algorithm against a variety of attacks.
A Biophysical Approach to Predicting Protein-DNA Binding Energetics

Sequence-specific interactions between proteins and DNA play a central role in DNA replication, repair, recombination, and control of gene expression. These interactions can be studied in vitro using microfluidics, protein-binding microarrays (PBMs), and other high-throughput techniques. Here we develop a biophysical approach to predicting protein–DNA binding specificities from high-throughput in vitro data. Our algorithm, called BindSter, can model alternative DNA-binding modes and multiple protein species competing for access to DNA, while rigorously taking into account all sterically allowed configurations of DNA-bound factors. BindSter can be used with a hierarchy of protein–DNA interaction models of increasing complexity, including contributions of mononucleotides, dinucleotides, and longer words to the total protein–DNA binding energy. We observe that the quality of BindSter predictions does not change significantly as some of the energy parameters vary over a sizable range. To take this degeneracy into account, we have developed a graphical representation of parameter uncertainties called IntervalLogo. We find that our simplest model, in which each nucleotide in the binding site is treated independently, performs better than previous biophysical approaches. The extensions of this model, in which contributions of longer words are also considered, result in further improvements, underscoring the importance of higher-order effects in protein–DNA energetics. In contrast, we find little evidence of multiple binding modes for the transcription factors (TFs) and experimental conditions in our data set. Furthermore, there is limited consistency in predictions for the same TF based on microfluidics and PBM data.
Overcoming Apartheid: Can Truth Reconcile a Divided Nation?

Throughout the world, truth commissions are being constructed under the hope that discovering the “truth” about a country's conflictual past will somehow contribute to “reconciliation.” Most such efforts point to South Africa's process as an exemplar of the powerful influence of truth finding. But has truth actually contributed to reconciliation in South Africa? No rigorous and systematic assessment of the truth and reconciliation process has ever been conducted. This article investigates the hypothesis that truth leads to reconciliation. Based on a survey of thirty-seven hundred South Africans in 2001, the author begins by giving both “truth” and “reconciliation” clear conceptual and operational meaning. The author reports empirical evidence that the Truth and Reconciliation Commission's “truth” is fairly widely accepted by South Africans of all races, that some degree of reconciliation characterizes South Africa today, and that the collective memory produced by the process (“truth”) did indeed contribut...
To reduce or to extend a spacecraft design lifetime

The engineering and economic issues at stake for reducing or extending a complex system’s design lifetime are investigated using a spacecraft as an example. These issues are examined from an operator perspective, a manufacturer’s perspective, as well as from the perspective of society at large. The question of whether there is an optimal design lifetime for complex engineering systems in general, and spacecraft in particular, and what it takes to answer this question is addressed. Preliminary results indicate that optimal design lifetimes do exist that maximize a system’s value metric. Therefore, even if it is technically feasible to field a system or launch spacecraft with a longer lifetime, it is not necessarily in the best interest of an operator, and definitely not in the interest of the manufacturer, to do so. Preliminary results also show that the design lifetime is, in the case of a spacecraft, a key requirement in sizing various subsystems and, consequently, has a significant impact on the overall cost of the spacecraft. Additionally, at the level of the entire space industry value chain, the spacecraft design lifetime is a powerful lever that can significantly impact the whole space industry’s performance. Overall, it is shown that the selection of a spacecraft design lifetime begs careful consideration and requires much more attention than it has received so far in the literature because its impact will ripple throughout an entire industry value chain.
Existence and Construction of Capacity-Achieving Network Codes for Distributed Storage

In a distributed storage system based on erasure coding, when a storage node fails, repairing the erasure code incurs some network traffic. Previous work has characterized the fundamental tradeoff between storage efficiency and repair network bandwidth. This was done via a cut-based analysis on a graph that models the evolution of information flow in the storage system subject to arbitrary sequences of node failures/repairs. This paper presents techniques for constructing network codes that achieve the optimal tradeoff between storage efficiency and repair network bandwidth. The challenge here is that network coding is applied over an unbounded graph with an unbounded number of receivers. It is shown in this paper that optimal codes can be constructed over a finite field whose size depends only on the maximum number of nodes at any instant, but independent of how many failures/repairs can happen. Key to the code construction is a "path-weaving" procedure that leads to inductive existence proof and code construction.
Snowmelt on the Greenland Ice Sheet as Derived from Passive Microwave Satellite Data

Abstract The melt extent of the snow on the Greenland ice sheet is of considerable importance to the ice sheet’s mass and energy balance, as well as Arctic and global climates. By comparing passive microwave satellite data to field observations, variations in melt extent have been detected by establishing melt thresholds in the cross-polarized gradient ratio (XPGR). The XPGR, defined as the normalized difference between the 19-GHz horizontal channel and the 37-GHz vertical channel of the Special Sensor Microwave/Imager (SSM/I), exploits the different effects of snow wetness on different frequencies and polarizations and establishes a distinct melt signal. Using this XPGR melt signal, seasonal and interannual variations in snowmelt extent of the ice sheet are studied. The melt is found to be most extensive on the western side of the ice sheet and peaks in late July. Moreover, there is a notable increasing trend in melt area between the years 1979 and 1991 of 4.4% per year, which came to an abrupt halt in 1...
Information Acquisition and Reputation Dynamics

We study dynamic incentives and behaviour in markets with costly discovery of past transactions. In our model, a sequence of short-lived customers interact over time with a single long-lived firm that privately knows its type (good or opportunistic). Customers must pay to observe the firm's past behaviour. We characterize the equilibrium structure that features accumulation, consumption, and restoration of reputation. The opportunistic firm deliberately builds its reputation up to a point where the maximum periods of information acquired by customers do not reveal past opportunistic behaviour and exploits the customers who most trust the firm. Copyright 2011, Oxford University Press.
Lg Depth Estimation and Ripple Fire Characterization Using Artificial Neural Networks

This srudy has demonstrated how artificial neural networks (ANNs) can be used to characterize seismic sources using high-frequency regional seismic data. We have taken the novel approach of using ANNs as a research tool for obtaining seismic source information, specifically depth of focus for earthquakes and ripple-fire characteristics for economic blasts, rather than as just a feature classifier between earthquake and explosion populations. Overall, we have found that ANNs have potential applications to seismic event characterization and identification, beyond just as a feature classifier. In future studies, these techniques should be applied to actual data of regional seismic events recorded at the new regional seismic arrays. The results of this study indicates that an ANN should be evaluated as part of an operational seismic event identification system.
Quantum algorithm for obtaining the energy spectrum of molecular systems

Simulating a quantum system is more efficient on a quantum computer than on a classical computer. The time required for solving the Schrodinger equation to obtain molecular energies has been demonstrated to scale polynomially with system size on a quantum computer, in contrast to the well-known result of exponential scaling on a classical computer. In this paper, we present a quantum algorithm to obtain the energy spectrum of molecular systems based on the multiconfigurational self-consistent field (MCSCF) wave function. By using a MCSCF wave function as the initial guess, the excited states are accessible. Entire potential energy surfaces of molecules can be studied more efficiently than if the simpler Hartree-Fock guess was employed. We show that a small increase of the MCSCF space can dramatically increase the success probability of the quantum algorithm, even in regions of the potential energy surface that are far from the equilibrium geometry. For the treatment of larger systems, a multi-reference configuration interaction approach is suggested. We demonstrate that such an algorithm can be used to obtain the energy spectrum of the water molecule.
Virtual remote center of motion control for needle placement robots.

Surgical robots, including those with remote center of motion (RCM) mechanisms, have demonstrated utility in image-guided percutaneous needle placement procedures. However, widespread clinical application of these robots is hindered by not only complicated mechanical design but also the need for calibration and registration of the robot to the medical imager prior to each use. In response, we propose a Virtual RCM algorithm that requires only online tracking or registering the surgical tool to the imager, and a five degree-of-freedom (DOF) robot comprised of three prismatic DOF decoupled from two rotational DOF. The robot can be unencoded, uncalibrated, and does not require pre-operative registration. An incremental adaptive motion control cycle both guides the needle to the insertion point and orients it to align with the target. The robot executes RCM motion “virtually” without having a physically constrained fulcrum point. The proof-of-concept prototype system achieved 0.78 mm translation and 1.4 degrees rotational accuracy (within the tracker accuracy), within 17 iterative steps (0.5–1s).
A high-accuracy algorithm for designing arbitrary holographic atom traps

We report the realization of a new iterative Fourier-transform algorithm for creating holograms that can diffract light into an arbitrary two-dimensional intensity profile. We show that the predicted intensity distributions are smooth with a fractional error from the target distribution at the percent level. We demonstrate that this new algorithm outperforms the most frequently used alternatives typically by one and two orders of magnitude in accuracy and roughness, respectively. The techniques described in this paper outline a path to creating arbitrary holographic atom traps in which the only remaining hurdle is physical implementation.
Size-biased branching population measures and the multi-type x log x condition

We investigate the xlog x condition for a general (Crump–Mode– Jagers) multi-type branching process with a general type space by constructing a size-biased population measure that relates to the ordinary population measure via an intrinsic martingale Wt. Sufficiency of the xlog x condition for a non-degenerate limit of Wt is proved and conditions for necessity are investigated. GENERAL BRANCHING PROCESS; XLOGX CONDITION; IMMIGRATION; SIZE-BIASED MEASURE
A unified concept of stress in plants

Consideration of a unified concept of stress resistance in plants is often prompted by the numerous examples where seasonal variation in resistance, to a particular environmental stress is paralleled by increased resistance to other stresses. As early as 1929, Maximov discussed Walter’s (1925) suggestion that there is a close analogy between freezing and drought resistance. Scarth (1941), drawing upon data of Levitt and Siminovitch (1940), reported that the relative resistance to desiccation, freezing and plasmolysis was equal in such diverse tissues as cabbage petioles and cortex tissue of Catalpa and Cornus twigs. Pisek and Larcher (1954) have documented that several conifers and broad-leaved evergreens exhibit parallel trends in drought and freezing resistance, while Parker (1972) indicates that seasonal trends in heat resistance of various species of conifers and broad-leaved evergreens resemble those for freezing resistance. Coffman (1957) demonstrated a parallelism between freezing resistance and heat resistance of twelve varieties of two Avena species, while Sullivan and Ross (1979) reported positive correlations between levels of cellular desiccation tolerance and heat tolerance.
A combination theorem for Veech subgroups of the mapping class group

In this paper we prove a combination theorem for Veech subgroups of the mapping class group analogous to the first Klein–Maskit combination theorem for Kleinian groups in which two Fuchsian subgroups are amalgamated along a parabolic subgroup. As a corollary, we construct subgroups of the mapping class group (for all genera at least 2), which are isomorphic to non-abelian closed surface groups in which all but one conjugacy class (up to powers) is pseudo-Anosov.
Structure–function relationships in peptoids: Recent advances toward deciphering the structural requirements for biological function

Oligomers of N-substituted glycine, or peptoids, are versatile tools to probe biological processes and hold promise as therapeutic agents. An underlying theme in the majority of recent peptoid research is the connection between peptoid function and peptoid structure. For certain applications, well-folded peptoids are essential for activity, while unstructured peptoids appear to suffice, or even are superior, for other applications. Currently, these structure–function connections are largely made after the design, synthesis, and characterization process. However, as guidelines for peptoid folding are elucidated and the known biological activities are expanded, we anticipate these connections will provide a pathway toward the de novo design of functional peptoids. In this perspective, we review several of the peptoid structure–function relationships that have been delineated over the past five years.
The Effect of Pitch Accenting on Pronoun Referent Resolution

By strictest interpretation, theories of both centering and intonational meaning fail to predict the existence of pitch accented pronominals. Yet they occur felicitously in spoken discourse. To explain this, I emphasize the dual functions served by pitch accents, as markers of both propositional (semantic/pragmatic) and attentional salience. This distinction underlies my proposals about the attentional consequences of pitch accents when applied to pronominals, in particular, that while most pitch accents may weaken or reinforce a cospecifier's status as the center of attention, a contrastively stressed pronominal may force a shift, even when contraindicated by textual features.
Coal Mining and the Resource Curse in the Eastern United States

We measure the effect of resource-sector dependence on long-run income growth using the natural experiment of coal mining in 409 Appalachian counties selected for homogeneity. Using a panel data set (1970–2010), we find a one standard deviation increase in resource dependence is associated with 0.5–1 percentage point long-run and a 0.2 percentage point short-run decline in the annual growth rate of per capita personal income. We also measure the extent to which the resource curse operates through disincentives to education, and find significant effects, but this “education channel” explains less than 15 percent of the apparent curse.
You share, i share: network effects and economic incentives in P2P file-sharing systems

We study the interaction between network effects and external incentives on file sharing behavior in Peer-to-Peer (P2P) networks. Many current or envisioned P2P networks reward individuals for sharing files, via financial incentives or social recognition. Peers weigh this reward against the cost of sharing incurred when others download the shared file. As a result, if other nearby nodes share files as well, the cost to an individual node decreases. Such positive network sharing effects can be expected to increase the rate of peers who share files. In this paper, we formulate a natural model for the network effects of sharing behavior, which we term the "demand model." We prove that the model has desirable concavity properties, meaning that the network benefit of increasing payments decreases when the payments are already high. This result holds quite generally, for submodular objective functions on the part of the network operator. In fact, we show a stronger result: the demand model leads to a "coverage process," meaning that there is a distribution over graphs such that reachability under this distribution exactly captures the joint distribution of nodes which end up sharing. The existence of such distributions has advantages in simulating and estimating the performance of the system. We establish this result via a general theorem characterizing which types of models lead to coverage processes, and also show that all coverage processes possess the desirable submodular properties. We complement our theoretical results with experiments on several realworld P2P topologies. We compare our model quantitatively against more naive models ignoring network effects. A main outcome of the experiments is that a good incentive scheme should make the reward dependent on a node's degree in the network.
A soluble base for the copper-catalyzed imidazole N-arylations with aryl halides.

CuI-catalyzed N-arylation of imidazoles with aryl bromides has been achieved in a near-homogeneous system that utilizes tetraethylammonium carbonate as base, 8-hydroxyquinoline as ligand, and H2O as cosolvent. Preliminary results with aryl chlorides are also reported.
Defect Chemistry of BaTiO3 with Additions of CaTiO3

The substitution of up to 5% Ca2+ for Ba2+ in BaTiO3 results in a shift in the oxygen pressure dependence of the equilibrium electrical conductivity that is in the same direction as that caused by addition of acceptor impurities such as Al3+ or Ca2+ substituted for Ti4+. In contrast to the latter effect, however, the shape of the conductivity plot is not changed, the conductivity value at the conductivity minimum is not affected, and the amount of the shift increases with decreasing temperature of measurement. It is shown that the shift is primarily due to an increase in the enthalpy of reduction and a decrease in the enthalpy of oxidation as increasing amounts of Ba2+ are replaced by Ca2+.
The Effects of Labor Unions on Employment, Wages, and Days of Operation: Coal Mining in West Virginia

We present a framework for measuring the joint impact of labor unions on wages, employment, and days of work. Our particular application uses county level observations to measure the impact of unionism in West Virginia coal mining from 1897 to 1938. The widespread belief is that union-nonunion wage differentials in coal mining during this period were of the order of 50 percent or more. Our estimates are substantially less. We measure negligible differences in union-nonunion employment, while, in the 1920s, operating days in unionized mines were about 25 percent below those in nonunion mines.
Stability for large forbidden subgraphs

In this note we strengthen the stability theorem of Erdos and Simonovits. Write Kr(s1, …, sr) for the complete r-partite graph with classes of sizes s1, …, sr and Tr(n) for the r-partite Turan graph of order n. Our main result is: For all r≥2 and all sufficiently small c>0, e>0, every graph G of sufficiently large order n with e(G)>(1-1-r-e)n2-2 satisfies one of the conditions: G contains a \documentclass{article} \usepackage{amssymb}\footskip=0pc\pagestyle{empty} \begin{document} $K_{r+1} (\lfloor c\,\mbox{ln}\,n \rfloor,\ldots,\lfloor c\,\mbox{ln}\,n \rfloor,\lceil n^{{1}-\sqrt{c}}\rceil)$ \end{document}; G differs from Tr(n) in fewer than (e1-3+c1-(3r+3))n2 edges. Letting µ(G) be the spectral radius of G, we prove also a spectral stability theorem: For all r≥2 and all sufficiently small c>0, e>0, every graph G of sufficiently large order n with µ(G)>(1-1-r-e)n satisfies one of the conditions: G contains a \documentclass{article} \usepackage{amssymb}\footskip=0pc\pagestyle{empty} \begin{document} $K_{r+1}(\lfloor c\,\mbox{ln}\,n\rfloor,\ldots,\lfloor c\,\mbox{ln}\,n\rfloor,\lceil n^{1-\sqrt{c}}\rceil)$ \end{document}; G differs from Tr(n) in fewer than (e1-4+c1-(8r+8))n2 edges. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 362–368, 2009
Structural Nested Failure Time Models

Structural nested failure time models are causal models for the effect of a time-dependent treatment or exposure on a survival time outcome in the presence of time-dependent confounders. A time-dependent confounder is a repeatedly measured covariate, which acts as a confounder for future exposure measurements but is on the causal path between earlier exposure measurements and ultimate response (i.e. here it acts as intermediate variable). Standard epidemiologic methodology fails if time-dependent confounders are present. Under the essential condition of no unmeasured confounders (the mathematical definition of which is a central issue) these models allow for unbiased causal inference, generalizing Robins's g-computation algorithm. The models use as building blocks time-dependent accelerated failure time models. Important applications are intricate endogenous (feedback) selection effects in occupational epidemiology (healthy worker effect) and clinical epidemiology (AIDS treatment). Keywords: survival analysis; time-dependent confounder; observational epidemiology; no unmeasured confounder; causality; randomization; longitudinal studies; intermediate variable; g-computation; accelerated failure time models
Frequency-Domain Vibration Control of Distributed Gyroscopic Systems

A new method is presented for vibration control of distributed gyroscopic systems. The control is formulated in the Laplace transform domain. The transfer function a closed-loop system, consisting of the plant, a feedback control law and the dynamics of the sensing and actuation devices, is derived. Stability analyses of the closed-loop system use both the root locus method and the generalized Nyquist criterion. Two stability criteria are obtained. Design of stabilizing controllers is carried out for both colocation and noncolocation of the sensor and actuator. The effects of time-delay and noncolocation of the sensor and actuator on the system stability are analyzed. In addition, the relationship between the root locus method and the generalized Nyquist criterion is discussed.
Vacuum birefringence in a rotating magnetic field

In the line above equation (1d), `Maxwell equation' should read `Maxwell equations'. In equations (3a) and (3b), eiz should read eikz. The wave number k appears correctly in subsequent equations.
Merged Two-Stage Power Converter With Soft Charging Switched-Capacitor Stage in 180 nm CMOS

In this paper, we introduce a merged two-stage dc-dc power converter for low-voltage power delivery. By separating the transformation and regulation function of a dc-dc power converter into two stages, both large voltage transformation and high switching frequency can be achieved. We show how the switched-capacitor stage can operate under soft charging conditions by suitable control and integration (merging) of the two stages. This mode of operation enables improved efficiency and/or power density in the switched-capacitor stage. A 5-to-1 V, 0.8 W integrated dc-dc converter has been developed in 180 nm CMOS. The converter achieves a peak efficiency of 81%, with a regulation stage switching frequency of 10 MHz.
Adaptive feed array compensation system for reflector antenna surface distortion

The feasibility of a closed-loop adaptive feed array system for compensating reflector surface deformations is investigated. The performance characteristics (gain, sidelobe, level, pointing, etc.) of large communication antenna systems degrade as the reflector surface distorts mainly due to thermal effects from a varying solar flux. The compensating systems described here can be used to maintain the design performance characteristics independent of thermal effects on the reflector surface. The proposed compensating system uses the concept of conjugate field matching to adjust the feed array complex excitation coefficients. To demonstrate the concept a simulated distorted reflector case is presented with several element patterns. >
Common agency lobbying over coalitions and policy

This paper presents a theory of common agency lobbying in which policy-interested lobbies can first influence the choice of a proto-coalition and then influence the legislative bargaining over policy within that coalition. The equilibrium policy in the legislative bargaining stage maximizes the aggregate policy utility of the coalition members and the lobbies, but lobbying can also lead to the preservation of the status quo and lobby-induced gridlock. When the status quo does not persist, the policy outcome is largely determined by the selection of a coalition, since legislative bargaining under unanimity within the coalition leads to a coalition-efficient policy regardless of the identity of the proposer. An example is presented to identify the types of equilibria and provide a full characterization of an equilibrium.
Nitrosopurines En Route to Potently Cytotoxic Asmarines

A nitrosopurine ene reaction easily assembles the asmarine pharmacophore and transmits remote stereochemistry to the diazepine-purine hetereocycle. This reaction generates potent cytotoxins which exceed the potency of asmarine A (1.2 μM IC50) and supersede the metabolites as useful leads for biological discovery.
Ports and Highways Infrastructure: An Analysis of Intra- and Interstate Spillovers

U.S. ports serve a vital role in the nation's supply chain and international trade. While the areas surrounding these ports bear the external costs of port expansion (congestion, air and noise pollution), neighboring regions feel the benefits and additional costs from port activity. Given the current debate over external costs from port activity, it is important to quantify the costs and benefits of ports on industry in the home state and neighboring states. This study assesses the role that transportation infrastructure plays in production and employment in the manufacturing industry. Using state-level data from the 48 contiguous states, the authors model manufacturing production and cost, incorporating state and local investment in port and highway infrastructure as variables. The authors find lower manufacturing costs in states with increased ports infrastructure. However manufacturing firms experience higher costs if a neighboring state increases its ports infrastructure, perhaps because productive re...
Facile and Efficient Synthesis of meso-Arylamino- and Alkylamino-Substituted Porphyrins via Palladium-Catalyzed Amination

meso-Arylamino- and alkylamino-substituted porphyrins were efficiently synthesized by reactions of meso-halogenated porphyrins with amines via palladium-catalyzed amination. The combination of palladium acetate and the commercially available phosphine ligand bis(2-diphenylphosphinophenyl) ether (DPEphos) is effective for catalyzing the couplings of both [5-bromo-10,20-diphenyl porphyrino]zinc(II) and [5,15-dibromo-10,20-diphenylporphyrino]zinc(II) with amines to give the corresponding monoamino- and diamino-substituted porphyrins in high yields under mild conditions. The corresponding halogenated free-base porphyrins also underwent the cross-coupling reactions efficiently under similar catalytic conditions.
The first crystal structure characterization of a semibuckminsterfullerene, and a novel synthetic route

Tetrabromosemibuckminsterfullerene 6, obtained by a novel synthetic route, is converted to the tetramethyl derivative 7; X-ray crystal structure determination of the latter reveals a highly nonplanar, bowl-shaped molecule with solvating CCl4 molecules separating the hydrocarbon moieties.
The bias of integrated assessment models that ignore climate catastrophes

Climate scientists currently predict there is a small but real possibility that climate change will lead to civilization threatening catastrophic events. Martin Weitzman has used this evidence along with his controversial “Dismal Theorem” to argue that integrated assessment models of climate change cannot be used to determine an optimal price for carbon dioxide. In this paper, I provide additional support for Weitzman’s conclusions by running numerical simulations to estimate risk premiums toward climate catastrophes. Compared to the assumptions found in most integrated assessment models, I incorporate into the model a more realistic range of uncertainty for both climate catastrophes and societal risk aversion. The resulting range of risk premiums indicates that the conclusions drawn from integrated assessment models that do not incorporate the potential for climate catastrophes are too imprecise to support any particular policy recommendation. The analysis of this paper is more straightforward and less technical than Weitzman’s, and therefore the conclusions should be accessible to a wider audience.
How Do Judges Think about Risk

A sample of almost 100 judges exhibited well-known patterns of biases in risk beliefs and reasonable implicit values of life. These biases and personal preferences largely do not affect attitudes toward judicial risk decisions, though there are some exceptions, such as ambiguity aversion, misinterpretation of negligence rules, and retrospective risk assessments in accident cases, which is a form of hindsight bias. Although judges avoided many pitfalls exhibited by jurors and the population at large, they nevertheless exhibited systematic errors, particularly for small probability-large loss events. These findings highlighted the importance of judicial review and the input of expert risk analysts to assist judicial decisions in complex risk cases.
Preparation of meso-tetra(4-galvinolphenyl)porphyrin : a building block for molecular magnetic materials

Abstract The synthesis and oxidative electrochemistry of a free-radical substituted metalloporphyrin are described. The porphyrin is prepared in four steps in good yield. Oxidation at a platinum electrode shows the molecule undergoes five reversible one-electron transfers to a stable pentaradical.
The evolution of cash transactions: Some implications for monetary policy

This paper considers the implications for monetary policy of a decreasing demand for outside money. It finds that even perpetual declines in the demand for base money pose no threat to the traditional methods employed for conducting monetary policy. The effects of such reductions in the demand for central bank liabilities, however, do depend on how monetary policy is conducted. Four monetary policy regimes are analyzed. With a policy of nominal-interest-rate targeting, a secular decline in the volume of cash transactions unambiguously leads to accelerating inflation. A policy of maintaining a fixed composition of government liabilities leads to accelerating (decelerating) inflation if agents have sufficiently high (low) levels of risk aversion. Inflation targeting produces falling nominal and real interest rates, while a policy of fixing the rate of money growth can easily lead to indeterminacy and endogenous oscillation in interest rates. It is argued that a policy of fixing the composition of government liabilities has several advantages if it is known that agents are not too risk averse and that the asymptotic demand for base money is small. If this information is not known, then interest-rate or inflation targeting have an advantage because their consequences are not sensitive to such environmental features.