cssi/SciSciGPT-SciSciNet huggingface dataset:
Highway to success in India : the impact of the golden quadrilateral project for the location and performance of manufacturing

The infrastructure gap is one of the most significant impediments to India realizing its growth and poverty reduction potential. Although Indias transport network is one of the most extensive in the world, accessibility and connectivity are limited. Only 20 percent of the national highway network (which carries 40 percent of traffic) is four-lane and one-fourth of the rural population does not have access to an all-weather road. It is estimated that the transport sector alone will require an investment of nearly US$500 billion over the next 10 years. This paper investigates the impact of the Golden Quadrilateral highway project on the Indian organized manufacturing sector using enterprise data. The Golden Quadrilateral project upgraded the quality and width of 5,846 km of roads in India. The analysis uses a difference-in-difference estimation strategy to compare non-nodal districts based on their distance from the highway system. It finds several positive effects for non-nodal districts located 0-10 km from the Golden Quadrilateral that are not present in districts 10-50 km away, most notably higher entry rates and increases in plant productivity. These results are not present for districts located on another major highway system, the North-South East-West corridor. Improvements for portions of the North-South East-West corridor system were planned to occur at the same time as the Golden Quadrilateral but were subsequently delayed. Additional tests show that the Golden Quadrilateral projects effect operates in part through a stronger sorting of land-intensive industries from nodal districts to non-nodal districts located on the Golden Quadrilateral network. The Golden Quadrilateral upgrades further helped spread economic activity to moderate-density districts and intermediate size cities.
POST-CARTEL PRICING DURING LITIGATION

Standard methods in the U.S. for calculating antitrust damages in price-fixing cases are shown to create a strategic incentive for firms to price above the non-collusive price after the cartel has been dissolved. This results in an overestimate of the but for price and an underestimate of the level of damages. The extent of this upward bias in the but for price is greater, the longer the cartel was in place and the more concentrated the industry.
Alternative Route to the Diisocyanate Building Block 1,4-Diisocyanato-4-methylpentane (DIMP)

The synthesis of 1,4-diisocyanato-4-methylpentane was accomplished starting from isobutyronitrile in six steps with 53% overall yield. The two isocyanates were installed by a double Curtius rearrangement. The product reacts with alcohol in a regioselective manner.
Witten's conjecture and Property P

Let K be a non-trivial knot in the 3{sphere and let Y be the 3{manifold obtained by surgery on K with surgery-coecient 1. Using tools from gauge theory and symplectic topology, it is shown that the fundamental group of Y admits a non-trivial homomorphism to the group SO(3). In particular, Y cannot be a homotopy-sphere.
Who gets debt relief

We use preliminary results from an ongoing effort to construct estimates of debt relief to study its allocation across a sample of 62 low-income countries. We find some evidence that debt relief, particularly from multilateral creditors, has been allocated to countries with better policies in recent years. Somewhat surprisingly, conditional on per capita incomes and policy, more indebted countries are not much more likely to receive debt relief. However, countries that are large debtors vis-a-vis especially multilateral creditors are more likely to receive debt relief. We do not find much evidence that debt relief responds to shocks to GDP growth. Finally, most of the persistence in debt relief is driven by slowly-changing country characteristics, indicating that it may be difficult for countries to "exit" from cycles of repeated debt relief.
General Linear Cameras

We present a General Linear Camera (GLC) model that unifies many previous camera models into a single representation. The GLC model is capable of describing all perspective (pinhole), orthographic, and many multiperspective (including pushbroom and two-slit) cameras, as well as epipolar plane images. It also includes three new and previously unexplored multiperspective linear cameras. Our GLC model is both general and linear in the sense that, given any vector space where rays are represented as points, it describes all 2D affine subspaces (planes) that can be formed by affine combinations of 3 rays. The incident radiance seen along the rays found on subregions of these 2D affine subspaces are a precise definition of a projected image of a 3D scene. The GLC model also provides an intuitive physical interpretation, which can be used to characterize real imaging systems. Finally, since the GLC model provides a complete description of all 2D affine subspaces, it can be used as a tool for first-order differential analysis of arbitrary (higher-order) multiperspective imaging systems.
Fuel-optimal trajectories of aeroassisted orbital transfer with plane change

The fuel-optimal control problem arising in noncoplanar orbital transfer employing aeroassist technology is addressed. The mission involves the transfer from high Earth orbit to low Earth orbit with plane change. The complete maneuver consists of a deorbit impulse to inject a vehicle from a circular orbit to an elliptic orbit for atmospheric entry, a boost impulse at the exit from the atmosphere for the vehicle to attain a desired orbital altitude, and a reorbit impulse to circularize the path of the vehicle. In order to minimize the total fuel consumption, a performance index is chosen as the sum of the deorbit, boost, and reorbit impulses. The application of optimization principles leads to a nonlinear, two-point, boundary value problem, which is solved by a multiple shooting method. >
Tharsis recharge: A source of groundwater for Martian outflow channels

[1] The large martian outflow channels terminating in Chryse Planitia are remnants of flooding events involving the localized discharge of millions of cubic kilometers of subsurface water, more than can be regionally stored in the crust. We use a dynamic groundwater model to demonstrate that snowpack or glaciers on the Tharsis rise, formed during periods of high obliquity when ice was stable at low latitudes, may have provided an efficient source of recharge and hydraulic head for the circum-Chryse outflow channels. Water is discharged through the outflow channels several times faster in Tharsis recharge models than in comparable South Pole recharge models.
Procurement Contracting With Time Incentives: Theory and Evidence

In public procurement, social welfare often depends on how quickly the good is delivered. A leading example is highway construction, where slow completion inflicts a negative externality on commuters. In response, highway departments award some contracts using scoring auctions, which give contractors explicit incentives for accelerated delivery. We characterize efficient design of these mechanisms. We then gather an extensive data set of highway projects awarded by the California Department of Transportation between 2003 and 2008. By comparing otherwise similar contracts, we show that where the scoring design was used, contracts were completed 30--40% faster and the welfare gains to commuters exceeded the increase in procurement costs. Using a structural model that endogenizes participation and bidding, we estimate that the counterfactual welfare gain from switching all contracts from the standard design to the efficient ApB design is nearly 22% of the total contract value ($1.14 billion). Copyright 2011, Oxford University Press.
Governing the economy: The politics of state intervention in Britain and France

For over one hundred years, the British economy has been in decline relative to other industrialized countries. This book explores the origins of Britain's economic problems and develops a striking new argument about the sources of decline. It goes on to analyze the evolution of economic policy in postwar Britain from the development of Keynesianism to the rise of monetarism under Margaret Thatcher. France, by contrast, experienced an economic miracle in the postwar period. Hall argues that the French state transformed itself and then its society through an extensive system of state intervention. In the recent period, however, the French system has encountered many difficulties, and the book locates their sources in the complex interaction between state and society in France culminating in the socialist experiment of Francois Mitterrand. Through his insightful, comparative examination of policy-making in Britain and France, Hall develops a new approach to state-society relations that emphasizes the crucial role of institutional structures.
Stereoselective synthesis of functionalized precursors of the CDEF and CDE 2,6-dideoxy-tetra- and trisaccharide units of durhamycins A and B.

Highly stereoselective syntheses of functionalized precursors of the CDEF and CDE 2,6-dideoxy-tetra- and trisaccharide units of the anti-HIV aureolic acids durhamycins A and B using 2-deoxy-2-iodo- and 2-deoxy-2-bromopyranosyl donors are described.
Impact of Farmland Preservation Programs on the Rate of Urban Development

Due to high losses of agricultural land in urbanizing areas over the past several years, state and local governments have adopted zoning regulations, right-to-farm ordinances, preferential property tax programs, and other means to protect agricultural land resources. Critics of the farmland preservation efforts note that these programs may only delay the ultimate conversion of farmland to urban uses and may simply shift urban development to neighboring areas (positive spillover effects). An alternative means of permanently protecting farmland is provided by purchase of development rights (PDR) programs, which enroll acreage from landowners who voluntarily sell the development rights to their farmland. Although ownership and all other property rights are retained by the owner, the option to develop the land for urban uses is removed from the current and all subsequent landowners. The purpose of this paper is to develop an empirical model of the impact of PDR programs on urban land development rates. To estimate the empirical model, we form a dependent variable based on county level rates of urban development from the USDA National Resources Inventory (NRI) data base for nine states in the Northeast US that have adopted farmland protection measures during the sample period (1982-1997). The set of explanatory variables include dummy variables for the existence of an active PDR program in the county and active PDR programs in adjacent counties plus measures of demographics, farm returns, population growth, income, and site-specific factors gathered from several sources (e.g., Census of Agriculture, Census of Population, and USDA). The model is estimated using the ordinary least squares technique. Two key policy-relevant hypotheses: (1) PDR programs did not reduce the rate of urban development and (2) PDR programs did not induce positive spillover effects on neighboring counties. The test results suggest that PDRs may have had important more significant impact in the earlier years and did not cause positive spillover effects.
Large deviations for stable like random walks on $\mathbb Z^d$ with applications to random walks on wreath products

We derive Donsker-Vardhan type results for functionals of the occupation times when the underlying random walk on $\mathbb Z^d$ is in the domain of attraction of an operator stable law on $\mathbb R^d$. Applications to random walks on wreath products (also known as lamplighter groups) are given.
Connecting cognition and consumer choice

We describe what can be gained from connecting cognition and consumer choice by discussing two contexts ripe for interaction between the two fields. The first-context effects on choice-has already been addressed by cognitive science yielding insights about cognitive process but there is promise for more interaction. The second is learning and representation in choice where relevant theories in cognitive science could be informed by consumer choice, and in return, could pose and answer new questions. We conclude by discussing how these two fields of research stand to benefit from more interaction, citing examples of how interfaces of cognitive science with other fields have been illuminating for theories of cognition.
Modeling Recreation Demand when the Access Point is Unknown

The task of modeling the recreation demand for geographically large sites, such as rivers and beaches or large parks with multiple entrances, is often challenged by incomplete information regarding the access point used by the individual. Traditionally, analysts have relied upon convenient approximations, dening travel time and travel distances on the basis of the midpoint of a river or beach segment or on the basis of the nearest access point to the site for each individual. In this paper, we instead treat the problem as one of aggregation, drawing upon and generalizing results from the aggregation literature. The resulting model yields a consistent framework for incorporating information on site characteristics and travel costs gathered at a ner level than that used to obtain trip counts. We use a series of Monte Carlo experiments to illustrate the performance of the traditional mid-point and nearest access point approximations. Our results suggest that, while the nearest access point approach provides a relatively good approximation to underlying preferences for a wide range of parameter specications, use of the midpoint approach to calculating travel cost can lead to signicant bias in the travel cost parameter and corresponding welfare calculations. Finally, we use our approach in modeling recreation demand for the major river systems in Iowa using data from the 2009 Iowa Rivers and River Corridors Survey.
Direct transition metal-catalyzed functionalization of heteroaromatic compounds

During the last two decades there has been considerable growth in the development of catalytic reactions capable of activating unreactive C–H bonds. These methods allow for the synthesis of complex molecules from easily available and cheaper precursors in a fewer number of steps. Naturally, the development of C–H activation methods for direct functionalization of heterocyclic molecules, invaluable building blocks for pharmaceutical and synthetic chemistry and material science, has received substantial attention as well. This critical review summarizes the progress made in this field until November 2006 (117 references).
The Influence of Supershells and Galactic Outflows on the Escape of Ionizing Radiation from Dwarf Starburst Galaxies

We study the escape of Lyman continuum radiation from the disks of dwarf starburst galaxies, with and without supershells, by solving the radiation transfer problem of stellar radiation through them. We model disks with Md ¼ 10 8 10 10 M� , with exponential surface density profiles as a function of redshift, and model the effects of repeated supernova explosions driving supershells out of the disks, using the hydrodynamic simulation code ZEUS-3D. The amount of star formation is assumed proportional to mass above some density threshold. We vary the threshold to explore the range of star formation efficiencies, f� ¼ 0:006, 0.06, and 0.6. We find that the interstellar gas swept up in dense supershells can effectively trap the ionizing photons before the supershells blow out of the disks. The blowouts then create galactic outflows, chimneys that allow the photons to escape directly to the intergalactic medium. Our results are consistent with escape fractions of less than 0.1 measured in local dwarf starburst galaxies, because they are likely observed while the starbursts are young, before blowout. We suggest that high-redshift dwarf starburst galaxies may make a substantial contribution to the UV background radiation with total escape fractions e0.2, as expected if star formation efficiencies are e0:06. Subject headings: galaxies: dwarf — galaxies: formation — galaxies: starburst — H ii regions — ISM: bubbles
Running a Quantum Circuit at the Speed of Data

We analyze circuits for kernels from popular quantum computing applications, characterizing the hardware resources necessary to take ancilla preparation off the critical path. The result is a chip entirely dominated by ancilla generation circuits. To address this issue, we introduce optimized ancilla factories and analyze theirstructure and physical layout for ion trap technology. We introduce a new quantum computing architecture with highly concentrated data-only regions surrounded by shared ancilla factories. The results are a reduced dependence on costly teleportation, more efficient distribution of generated ancillae and more than five times speedup over previous proposals.
Optimal Sensor Location in Motion Control of Flexibly Supported Long Reach Manipulators

Long reach manipulator systems (LRMS) can perform tasks in difficult to reach locations. They use a small and fast manipulator mounted on a large flexible structure that can vibrate, degrading the system performance. Control methods that use strain measurements of the flexible structure have been proposed to control the system's position in spite of the supporting structure's vibrations using a model of the structure that relates strains to displacements. Here the minimum number of strain sensors needed to accomplish this control and their optimal locations on the flexible supporting structure are determined. These locations have been selected to achieve high measurement resolution, to maximize the computational robustness and to minimize the error in the identification of the structure's straindisplacement model. The results are validated with simulations and experiments using a six degree of freedom laboratory LRMS.
The effect of step length, cadence, and walking speed on the trunk's vertical excursion

Gait analysis is useful in the evaluation and treatment of musculoskeletal and neurological disorders, and it is beneficial in the assessment of prosthetic and orthotic performance during walking. An understanding of the relationship between step length, cadence, walking speed, and vertical excursion of the trunk can help in analyzing and comparing healthy and pathological gait. Theoretical and empirical relationships between the vertical excursion and walking speed were analyzed for freely selected, constant step length, and constant cadence gaits. A rocker-based inverted pendulum model was used to derive mathematical relationships between walking speed and vertical trunk movement. The theoretical work was supported by data that was acquired from able-bodied adult male subjects walking across a range of speeds. The authors determined that the trunk's vertical excursion is determined only by step length and leg geometry, and not cadence. Freely selected gait is characterized by a linear relationship between the trunk's vertical excursion and walking speed. A constant cadence gait produces a quadratic relationship between vertical displacement and walking speed, while for a constant step length gait the vertical excursion was invariant with walking speed.
Effect of severe neonatal morbidities on long term outcome in extremely low birthweight infants.

Purpose: To assess the validity of individual and combined prognostic effects of severe bronchopulmonary dysplasia (BPD), brain injury, retinopathy of prematurity (ROP), and parenteral nutrition associated cholestasis (PNAC). Methods: We retrospectively analyzed the medical records of 80 extremely low birthweight (ELBW) infants admitted to the neonatal intensive care unit (NICU) of the Severance Children’s Hospital, and who survived to a postmenstrual age of 36 weeks. We analyzed the relationship between 4 neonatal morbidities (severe BPD, severe brain injury, severe ROP, and severe PNAC) and poor outcome. Poor outcome indicated death after a postmenstrual age of 36 weeks or survival with neurosensory impairment (cerebral palsy, delayed development, hearing loss, or blindness) between 18 and 24 months of corrected age. Results: Each neonatal morbidity correlated with poor outcome on univariate analysis. Multiple logistic regression analysis revealed that the odds ratios (OR) were 4.9 (95% confidence interval [CI], 1.022.6; P=0.044) for severe BPD, 13.2 (3.0-57.3; P<.001) for severe brain injury, 5.3 (1.6-18.1; P=0.007) for severe ROP, and 3.4 (0.522.7; P=0.215) for severe PNAC. Severe BPD, brain injury, and ROP were significantly correlated with poor outcome, but not severe PNAC. By increasing the morbidity count, the rate of poor outcome was significantly increased (OR 5.2; 95% CI, 2.2-11.9; P<.001). In infants free of the above-mentioned morbidities, the rate of poor outcome was 9%, while the corresponding rates in infants with 1, 2, and more than 3 neonatal morbidities were 46%, 69%, and 100%, respectively. Conclusion: In ELBW infants 3 common neonatal mornidifies, severe BPD, brain injury and ROP, strongly predicts the risk of poor outcome.
Black hole physics from Liouville theory

Abstract In a previous paper it was shown that the quantum consistency conditions for the dilaton-gravity theory of Callan et al., imply that the cosmological constant term undergoes a dilaton dependent renormalization, in such a manner that the theory can be written as a Liouville-like theory. In this paper we discuss the physical interpretation of the solutions of this theory. In particular we demonstrate explicitly how quantum corrections tame the black hole singularity. Finally we discuss Hawking radiation and find that it is asymptotically constant, but the value of the constant depends on an undetermined parameter.
Recent developments on multiscale, hierarchical modeling of chemical reactors

Abstract A multiscale, hierarchical computational framework is presented for modeling homogeneous–heterogeneous reactors, which exhibit a large disparity in length and time scales. Scales range from quantum, to atomistic, to mesoscopic, to macroscopic. The coupling mechanisms between scales are discussed and illustrated with examples from CO and CH4 oxidation on platinum. Estimation of reaction mechanism parameters, based on first principle quantum calculations and semi-empirical techniques, is briefly reviewed. These kinetic mechanisms are key input into molecular, continuum, or mesoscopic models. Some emphasis is placed on surface diffusion, which typically falls outside the realm of atomistic models, but it can affect reaction rates and pattern formation on catalytic surfaces. An efficient methodology for parameter optimization of multiscale models is also presented. Finally, we show how mesoscopic models constitute a promising alternative to atomistic Monte Carlo (MC) simulations to account for intermolecular forces, which cannot be properly captured through continuum, mean field (MF) models. Application of these mesoscopic theories to microporous catalysts, such as zeolites, is also discussed.
1,3-asymmetric induction in hydride addition reactions to β-substituted ketones. A model for chirality transfer

Abstract We report the 1,3-asymmetric induction observed in the additions of various hydride reagents to β-substituted ketones. Both the nature of the β-substituents and the size of the achiral alkyl group attached to the carbonyl moiety have a significant effect on the direction and degree of carbonyl diastereofacial selectivity. A revision of Cram's polar model for 1,3-asymmetric induction is proposed to account for these results.
Asymmetric Price Transmission and Food Retailers' Selling Strategies

Price transmission from farm to retail is a longstanding and important issue in agricultural marketing. Researchers, producers, and policy makers have been concerned that the transmission of farm price increases to retail may be more quickly and of a greater magnitude than that of farm price decreases.
A Comparison of Precipitation Forecast Skill between Small Convection-Allowing and Large Convection-Parameterizing Ensembles

An experiment has been designed to evaluate and compare precipitation forecasts from a 5-member, 4-km grid-spacing (ENS4) and a 15-member, 20-km grid-spacing (ENS20) Weather Research and Forecasting (WRF) model ensemble, which cover a similar domain over the central United States. The ensemble forecasts are initialized at 2100 UTC on 23 different dates and cover forecast lead times up to 33 h. Previous work has demonstrated that simulations using convection-allowing resolution (CAR; dx ; 4 km) have a better representation of the spatial and temporal statistical properties of convective precipitation than coarser models using convective parameterizations. In addition, higher resolution should lead to greater ensemble spread as smaller scales of motion are resolved. Thus, CAR ensembles should provide more accurate and reliable probabilistic forecasts than parameterized-convection resolution (PCR) ensembles. Computation of various precipitation skill metrics for probabilistic and deterministic forecasts reveals that ENS4 generally provides more accurate precipitation forecasts than ENS20, with the differences tending to be statistically significant for precipitation thresholds above 0.25 in. at forecast lead times of 9‐21 h (0600‐ 1800 UTC) for all accumulation intervals analyzed (1, 3, and 6 h). In addition, an analysis of rank histograms and statistical consistency reveals that faster error growth in ENS4 eventually leads to more reliable precipitation forecasts in ENS4 than in ENS20. For the cases examined, these results imply that the skill gained by increasing to CAR outweighs the skill lost by decreasing the ensemble size. Thus, when computational capabilities become available, it will be highly desirable to increase the ensemble resolution from PCR to CAR, even if the size of the ensemble has to be reduced.
The Dynamic Advertising Effect of Collegiate Athletics

I measure the spillover effect of intercollegiate athletics on the quantity and quality of applicants to institutions of higher education in the United States---an effect popularly known as the “Flutie effect.” I treat athletic success as a stock of goodwill that decays over time, similar to that of advertising. A major challenge is that privacy laws prevent us from observing information about the applicant pool. I overcome this challenge by using order statistic distribution to infer applicant quality from information on enrolled students. Using a flexible random-coefficients aggregate discrete choice model that accommodates heterogeneity in preferences for school quality and athletic success, as well as an extensive set of school fixed effects to control for unobserved quality in athletics and academics, I estimate the impact of athletic success on applicant quality and quantity. Overall, athletic success has a significant, long-term goodwill effect on future applications and quality. However, students with lower-than-average SAT scores tend to have a stronger preference for athletic success, whereas students with higher SAT scores have a greater preference for academic quality. Furthermore, the decay rate of athletics' goodwill is significant only for students with lower SAT scores, suggesting that the goodwill created by intercollegiate athletics resides more extensively with lower-scoring students than with their higher-scoring counterparts. But, surprisingly, athletic success impacts applications even among academically stronger students.
Amino-Protecting Groups Subject to Deblocking under Conditions of Nucleophilic Addition to a Michael Acceptor. Structure−Reactivity Studies and Use of the 2-(tert-Butylsulfonyl)-2-propenyloxycarbonyl (Bspoc) Group

A new type of amino-protecting group is described in which a Michael acceptor is incorporated into the protectant so that treatment with a nucleophile will trigger deblocking. Comparison of various Michael acceptors showed that for several key electron-withdrawing groups, the order of reactivity was C6H5SO2 > Me3CSO2 > COOEt > C6H5SO > C6H4NO2-p. The reactivity of the nucleophile (e.g., primary and secondary aliphatic amines) followed an order related to both intrinsic basicity and steric effects. β-Substituents in the Michael acceptor caused significant retardation of the deblocking process. The Bspoc function was chosen for initial elaboration into a practical system for use in peptide synthesis. Bspoc amino acid chlorides were used as coupling agents and silica-tethered secondary amines as deblocking agents. With the latter, deblocking occurs cleanly and no byproducts remain in the organic solvent in which the deblocking is executed.
Oil Prices and the Terms of Trade

Abstract The combination of substantial terms of trade variability and unstable correlation patterns of trade prices with output and trade volumes has led some to suggest a break in the link between trade volumes and prices. We find that oil accounts for much of the variation in the terms of trade over the last twenty five years and its quantitative role varies significantly over time. And since our dynamic general equilibrium model predicts that the economy responds differently to oil supply shocks than to other shocks, changes in their relative importance helps to account for the unstable correlations in the data.
Design Parameter Selection in the Presence of Noise

Themethod of imprecision is a design method whereby a multi-objective design problem is resolved by maximizing the overall degree ofdesigner preference: values are iteratively selected based on combining the degree of preference placed on them. Consider, however, design problems that exhibit multiple uncertainty forms (noise). In addition to degrees of preference(imprecision) there areprobabilistic uncertainties caused by, for example, measuring and fabrication limitations. There are also parameters that can take on any valuepossible within a specified range, such as a manufacturing or tuning adjustment. Finally, there may be parameters which mustnecessarily satisfly all values within the range over which they vary, such as a horsepower requirement over a motor's different speeds. This paper defines a “best” set of design parameters for design problems with such multiple uncertainty forms and requirements.
Preferential trading areas: investment and welfare effects when countries differ in their size

This paper examines the investment and welfare effects of a preferential trading area (PTA) on member and non-member countries when countries differ in their relative size. I numerically solve a three-country and two-good model to characterize equilibria pertaining to investment diverting and creating effects of a preferential trade area. I conclude that welfare benefits of a preferential trade area are non-negative for the member countries, and could go either way for the non-member countries depending on their relative size. There exist equilibria which, given the parameter values and the relative size, result in welfare improvement in non-member countries.
Building on Quicksand

Reliable systems have always been built out of unreliable components [1]. Early on, the reliable components were small such as mirrored disks or ECC (Error Correcting Codes) in core memory. These systems were designed such that failures of these small components were transparent to the application. Later, the size of the unreliable components grew larger and semantic challenges crept into the application when failures occurred. Fault tolerant algorithms comprise a set of idempotent subalgorithms. Between these idempotent sub-algorithms, state is sent across the failure boundaries of the unreliable components. The failure of an unreliable component can then be tolerated as a takeover by a backup, which uses the last known state and drives forward with a retry of the idempotent sub-algorithm. Classically, this has been done in a linear fashion (i.e. one step at a time). As the granularity of the unreliable component grows (from a mirrored disk to a system to a data center), the latency to communicate with a backup becomes unpalatable. This leads to a more relaxed model for fault tolerance. The primary system will acknowledge the work request and its actions without waiting to ensure that the backup is notified of the work. This improves the responsiveness of the system because the user is not delayed behind a slow interaction with the backup. There are two implications of asynchronous state capture: 1) Everything promised by the primary is probabilistic. There is always a chance that an untimely failure shortly after the promise results in a backup proceeding without knowledge of the commitment. Hence, nothing is guaranteed! 2) Applications must ensure eventual consistency [20]. Since work may be stuck in the primary after a failure and reappear later, the processing order for work cannot be guaranteed. Platform designers are struggling to make this easier for their applications. Emerging patterns of eventual consistency and probabilistic execution may soon yield a way for applications to express requirements for a “looser” form of consistency while providing availability in the face of ever larger failures. As we will also point out in this paper, the patterns of probabilistic execution and eventual consistency are applicable to intermittently connected application patterns. This paper recounts portions of the evolution of these trends, attempts to show the patterns that span these changes, and talks about future directions as we continue to “build on quicksand”.
Bridging the Gap : Identifying What is Holding Self-Employed Women Back in Ghana, Rwanda, Tanzania, the Republic of Congo, and Uganda

We explore the determinants of the gender gap in income earnings in five Sub-Saharan countries: the Republic of Congo, Ghana, Rwanda, Uganda, and Tanzania. We show that first, self-employment tends to provide marginally lower average income (with the exception of Ghana and men in Rwanda) and much higher variability in income compared to wage work. Women on average earn less than men both when they are self-employed and in wage employment but also have less volatile earnings. Using the quantile decomposition methods developed in Firpo, Fortin, and Lemieux (2007), we find that the dierences in observable choices and endowments explain the gender gap in earning for the self-employed that earn the least while the gap for the most successful male and female entrepreneurs is largely driven by dierences in returns to observable covariates in the majority of the countries. These results suggest a glass ceiling eect, wherein a large portion of the income gaps between high-earning men and women cannot be explained by observable characteristics. We conclude by looking at the variables that account for a larger portion of the gender gap explained by observable characteristics and find that hours of work and industry explain a higher fraction compared to standard human capital and demographic factors such as age and education.
General and Efficient Synthesis of Arylamino- and Alkylamino-Substituted Diphenylporphyrins and Tetraphenylporphyrins via Palladium-Catalyzed Multiple Amination Reactions

A series of arylamino- and alkylamino-substituted diphenylporphyrins and tetraphenylporphyrins were efficiently synthesized by reactions of brominated porphyrin precursors with amines via palladium-catalyzed amination. The multiple amination reactions are general and suitable for a variety of amines, affording the desired aminoporphyrins in good to excellent yields. Examples include aromatic and aliphatic amines, primary and secondary amines, electron-rich, -neutral, and -poor amines as well as heteroaromatic amines and imines.
Predictive validity of stated preference data: evidence from mountain bike park visits before and after trail system expansion

This article investigates the validity of stated preference data for use in recreation demand estimation. We use stated preference and revealed preference data from users of a mountain bike park collected before and after an expansion of the trail system. The ex-ante stated preference data elicited before the change exhibits hypothetical bias, but it would provide useful information for demand prediction.
TESTS FOR SUBSTRUCTURE IN GRAVITATIONAL LENSES

The flux anomalies in four-image gravitational lenses can be interpreted as evidence for the dark matter substructure predicted by cold dark matter (CDM) halo models. In principle, these flux anomalies could arise from alternate sources, such as absorption, scattering, or scintillation by the interstellar medium (ISM) of the lens galaxy, problems in the ellipsoidal macro models used to fit lens systems, or stellar microlensing. We apply several tests to the data that appear to rule out these alternate explanations. First, the radio flux anomalies show no significant dependence on wavelength, as would be expected for almost any propagation effect in the ISM or microlensing by the stars. Second, the flux anomaly distributions show the characteristic demagnifications of the brightest saddle point relative to the other images expected for low optical depth substructure, which cannot be mimicked by either the ISM or problems in the macro models. Microlensing by stars also cannot reproduce the suppression of the bright saddle points if the radio source sizes are consistent with the Compton limit for their angular sizes. Third, while it is possible to change the smooth lens models to fit the flux anomalies in some systems, we can rule out the necessary changes in all systems where we have additional lens constraints to check the models. Moreover, the parameters of these models are inconsistent with our present observations and expectations for the structure of galaxies. We conclude that low-mass halos remain the best explanation of the phenomenon.
Learning under Uncertainty: Networks in Crisis Management

This article examines learning in networks dealing with conditions of high uncertainty. The author examines the case of a crisis response network dealing with an exotic animal disease outbreak. The article identifies the basic difficulties of learning under crisis conditions. The network had to learn most of the elements taken for granted in more mature structural forms—the nature of the structural framework in which it was working, how to adapt that framework, the role and actions appropriate for each individual, and how to deal with unanticipated problems. The network pursued this learning in a variety of ways, including virtual learning, learning forums, learning from the past, using information systems and learning from other network members. Most critically, the network used standard operating procedures to provide a form of network memory and a command and control structure to reduce the institutional and strategic uncertainty inherent in networks.
Congressional Appropriations and the Electoral Connection

Congressional scholars have frequently reported dramatic shifts int he mood of Congress toward federal spending. In seeking to explain these fluctuations in congressional moods, we develop and estimate an "electoral connection" model of the congressional appropriations process. In this model appropriations decisions are seen to be the product of the responses of reelection-seeking members of Congress to the key political and economic variables in their environment.
The Effect of Workfare Policy on Social Movement Mobilizations

Abstract This article assesses the effect of workfare policy on social movement mobilizations in Argentina. The results suggest that an increase in workfare fueled the development of insurgency, and that ignoring simultaneity between workfare policy and protests leads to large biases.
Mixed models and reduced/selective integration displacement models for nonlinear shell analysis

Simple mixed models are developed for the geometrically nonlinear analysis of shells. A total Lagrangian description of the shell deformation is used, and the analytical formulation is based on a form of the nonlinear shallow shell theory with the effects of transverse shear deformation and bending-extensional coupling included. The fundamental unknowns consist of eight stress resultants and five generalized displacements of the shell, and the element characteristic arrays are obtained by using the Hellinger-Reissner mixed variational principle. The polynomial interpolation (or shape) functions used in approximating the stress resultants are, in general, of different degree than those used for approximating the generalized displacements. The stress resultants are discontinuous at the element boundaries and are eliminated on the element level. The equivalence and ‘near-equivalence’ between the mixed models developed herein and displacement models based on reduced/selective integration of both transverse shear and extensional energy terms is discussed. The use of reduction methods in conjunction with the mixed models is outlined and the advantages of mixed models over displacement models are delineated. Analytic expressions are derived for the rigid-body and spurious (or zero energy) models for the various mixed models and their equivalent displacement models. Also, the advantages of mixed models over equivalent displacement models are outlined. Numerical results are presented to demonstrate the high accuracy and effectiveness of the mixed models developed, and to compare their performance with other mixed models reported in the literature.
A space fiber-optic X-ray burst detector

Describes a novel, lightweight X-ray burst detector that can be embedded in a satellite structure, thus forming a "smart skin," which has minimal impact on the host satellite. The design is based on two types of optical fibers coupled to photodiodes. The first is a scintillating fiber, which gives a fast signal for timing. The second is a germanium-doped silica fiber, which darkens for a few milliseconds when irradiated with a burst of X-rays. The resulting slow signal is used to discriminate against electrostatic discharges. The coincidence of a fast signal from the scintillating fiber with a slow signal from the darkening fiber is the signature of an X-ray burst. The response is linear at low doses and becomes nonlinear at high doses. The authors have two techniques to test the instrument in a space experiment scheduled for 1994. First, a small, space-qualified flash X-ray unit can illuminate the fibers. Second, the authors can detect space background radiation. The cumulative dose will be monitored by RADFET dosimeters. Future work on embedding the fibers and the electronics as application specific integrated circuits (ASICs) in the spacecraft skin could lead to the use of these detectors on many satellites. >
The bloch-okounkov correlation functions of classical type

Bloch and Okounkov introduced an n-point correlation function on the infinite wedge space and found an elegant closed formula in terms of theta functions. This function has connections to Gromov-Witten theory, Hilbert schemes, symmetric groups, etc., and it can also be interpreted as correlation functions on integrable \(\widehat{{\mathfrak{gl}}}_\infty\) -modules of level one. Such \(\widehat{ {\mathfrak{gl}}}_\infty\) -correlation functions at higher levels were then calculated by Cheng and Wang.
Testing the Monophyly and Placement of Lepechinia in the Tribe Mentheae (Lamiaceae)

Lepechinia (Lamiaceae subf. Nepetoideae) is a New World genus composed of about 42 species distributed primarily from Northern California to Central Argentina. Previous morphological and molecular studies on Lepechinia have raised questions on the mono- phyly of the genus and its placement within the tribe Mentheae. In this paper the phylogenetic placement and monophyly of Lepechinia is examined within the context of the tribe Mentheae using cpDNA ( ycf1 and trnL-F ) and nrDNA (ITS and ETS) markers. Melissa is shown to be sister to Lepechinia in both cpDNA and nrDNA analyses, and the monotypic genera Chaunostoma and Neoeplingia are found to be embedded within Lepechinia . The subtribe Menthinae is shown to be paraphyletic, with several genera needing to be reassigned. In particular, Neoeplingia should be included within the subtribe Salviinae. The genera Heterolamium and Melissa , both previously unplaced with regard to subtribe, are now clearly assigned to the subtribes Nepetinae and Salviinae, respectively. The cpDNA marker ycf1 has great phylogenetic utility, and is shown to be 50% more informative than trnL-F for the taxa used in this study. Keywords—Chaunostoma , cpDNA , Melissa , molecular phylogeny , Neoeplingia , ycf1.
PARAMETRICALLY EXCITED HAMILTONIAN PARTIAL DIFFERENTIAL EQUATIONS

Consider a linear autonomous Hamiltonian system with a time-periodic bound state solution. In this paper we study the structural instability of this bound state relative to time almost periodic perturbations which are small, localized, and Hamiltonian. This class of perturbations includes those whose time dependence is periodic but encompasses a large class of those with finite (quasi-periodic) or infinitely many noncommensurate frequencies. Problems of the type considered arise in many areas of applications including ionization physics and the propagation of light in optical fibers in the presence of defects. The mechanism of instability is radiation damping due to resonant coupling of the bound state to the continuum modes by the time-dependent perturbation. This results in a transfer of energy from the discrete modes to the continuum. The rate of decay of solutions is slow and hence the decaying bound states can be viewed as metastable. These results generalize those of A. Soffer and M. I. Weinstein, who treated localized time-periodic perturbations of a particular form. In the present work, new analytical issues need to be addressed in view of (i) the presence of infinitely many frequencies which may resonate with the continuum as well as (ii) the possible accumulation of such resonances in the continuous spectrum. The theory is applied to a general class of Schrodinger operators.
Impact of the global economic crisis on Taipei, China's industrial structure and firm activity

i»?Confronted by the current global economic crisis, Taipei,Chinaâ€™s economy has suffered much like its neighbors. However, Taipei,China is different from other East Asia economies in several aspects. First, Taipei,Chinaâ€™s industrial organization is dominated by small and medium-sized enterprises (SMEs), unlike the chaebols of the Republic of Korea or the Japanese Kabushiki-gaish. Second, Taipei,China has experienced extraordinary â€œhollowing-outâ€ of its industrial base as many firms (both large and SMEs) have moved their manufacturing operation to Peopleâ€™s Republic of China (PRC). This is also manifested in the fact that Taipei,China has become one of the largest sources of FDI in the PRC, and Taipei,Chinaâ€™s trade dependency with the PRC is ever rising. A silver lining is that when the sub-prime crisis hit the United States and weakened her import demand, the aforementioned hollowing-out meant less direct employment impact on Taipei,China. However, given the dominance of SMEs in Taipei,China (97.6% of business establishments, and 77.1% of employment), it is of vital importance to develop ways to aid SMEs in surviving this crisis. Indeed, the government can utilize this crisis to reform and strengthen SMEs so they can continue to be the backbone of Taipei,Chinaâ€™s economy. In this paper, I discuss the strengths and weaknesses of SMEs in Taipei,China. Policy recommendations are presented to address the weaknesses of the SMEs, including short-run and long-run approaches.