cssi/SciSciGPT-SciSciNet huggingface dataset:
Hypergeometric functions over finite fields and their relations to algebraic curves.

In this work we present an explicit relation between the number of points on a family of algebraic curves over &#x1d53d;q and sums of values of certain hypergeometric functions over &#x1d53d;q. Moreover, we show that these hypergeometric functions can be explicitly related to the roots of the zeta function of the curve over &#x1d53d;q in some particular cases. A general conjecture relating these last two is presented and advances toward its proof are shown in the last section.
Processing Strategy for Producing Highly Anisotropic Silicon Nitride

Silicon nitride with a preferred orientation of large elongated grains was obtained by tape casting of raw powder slurry seeded with rodlike {beta}-Si{sub 3}N{sub 4} particles, followed by a gas pressure sintering under 1 MPa nitrogen pressure. The large elongated grains developed from seeds lay in planes parallel to the casting direction in a two-dimensional distribution. Increased fracture toughness (11.1 MPa {center_dot} m{sup 1/2}) and bending strength (1,100 MPa) were achieved in the direction perpendicular to the grains alignment compared to specimens with a random distribution of elongated grains. Moreover, the specimens exhibited a high Weibull modulus of 46 due to the uniform distribution of large grains.
The General Practice Computer System Project: A Doctor's Desktop for Australia

The Australian Department of Health and Family Services engaged the IBM consulting practice to develop a functional specification and technical architecture for a General Practice computer system (GPCS) in January, 1997. The project was completed in September, 1997. This paper describes the rationale for development of the specification, the process that was undertaken and provides an overview of the completed specification and architecture. The paper also explores a number of issues related to computing in general practice which were raised during the consultative process, and considers factors which were found to be important in obtaining adoption and use of computer technology on the doctor's desk.
SCOTT'S PROBLEM FOR PROPER SCOTT SETS

Some 40 years ago, Dana Scott proved that every countable Scott set is the standard system of a model of PA. Two decades later, Knight and Nadel extended his result to Scott sets of size !1. Here, I show that assuming the Proper Forcing Axiom (PFA), every A-proper Scott set is the standard system of a model of PA. I define that a Scott set X is proper if the quotient Boolean algebra X/Fin is a proper partial order and A-proper if X is addition- ally arithmetically closed. I also investigate the question of the existence of proper Scott sets. In this paper, I use the Proper Forcing Axiom (PFA) to make partial progress on a half-century-old question in the folklore of models of Peano Arithmetic about whether every Scott set is the standard system of a model of PA. The Proper Forcing Axiom is a generalization of Martin's Axiom that has found application in many areas of set theory in recent years. I will show that, assuming PFA, every arithmetically closed Scott set whose quotient Boolean algebra X/Fin is proper is the standard system of a model of PA. I will begin with some technical and historical details. We can associate to every model M of PA a certain collection of subsets of the natural numbers called its standard system, in short SSy(M). The natural numbers N form the initial segment of every model of PA. The standard system consists of sets that arise as intersections of the definable (with parameters) sets of the model with the standard part N. One thinks of the standard system as the traces left by the definable sets of the model on the natural numbers. A dierent way of characterizing sets in the standard system uses the notion of coding. Let us say that a set A N is coded in a model M if M has an element a such that (a)n = 1 if and only if n 2 A. Here, (a)x can refer to any of the reader's favorite methods of coding with elements of a model of PA, e.g., by defining (a)x as the x th digit in the binary expansion of a. It is easy to see that for nonstandard models we can equivalently define the standard system to be the collection of all subsets of the natural numbers coded in the model. What features characterize standard systems? Without reference to models of arithmetic, a standard system is just a particular collection of subsets of the natural numbers. Can we come up with a list of elementary (set theoretic, computability theoretic, etc.) properties that X P (N) must satisfy in order to be the standard system of some model of PA? The notion of a Scott set encapsulates three key features of standard systems. Definition 1.1. X P (N) is a Scott set if
Sensor network configuration under physical attacks

Sensor networks will typically operate in hostile environments, where they are susceptible to physical attacks resulting in physical node destructions. In this paper, we study impacts of physical attacks on network configuration w.r.t. lifetime. While lifetime is constrained by limited energies and has been addressed before, they are not applicable under physical attacks. In this paper, we define a practical sensor network lifetime problem under physical attacks. We then analytically determine the minimum number and sensor deployment plan to meet lifetime requirement under physical attacks. We make several important observations, including the high sensitivity of lifetime to physical attacks.
LEGAL EFFECTIVENESS AND EXTERNAL CAPITAL: THE ROLE OF FOREIGN DEBT

Previous research has documented weak, and sometimes conflicting, effects of legal quality on measures of firm debt. Using WorldScope data for 1,689 firms, as well as more detailed proprietary data for 315 firms across nine East Asian countries, the authors find that access to foreign financing appears to loosen borrowing constraints associated with poor legal systems. This helps resolve inconsistencies in prior findings and explains how legal protection is important for borrowing by firms. In particular, they find that legal effectiveness is important for determining the amount, maturity, and currency denomination of debt. The authors discuss several mechanisms by which firms can avoid the costs of poor legal systems with foreign borrowing. The paper contributes to the policy debate surrounding the importance of creditor rights for domestic lending.
Workers' remittances to developing countries : a survey with central banks on selected public policy issues

This paper presents the findings of a survey conducted by the World Bank of central banks in 40 developing countries across different regions in the world. The survey focused on the following topics: (1) coverage of national statistics on remittances, (2) cost of transferring and delivering remittances, (3) regulatory regime for remittance transactions, and (4) efforts of developing countries to channel remittance flows through formal financial institutions. The study finds that in most countries existing data do not reflect the full amount of remittance inflows that they receive every year. Coverage of instruments and financial institutions through which remittances take place is limited. Moreover, only a few countries measure remittances that take place through informal channels. It also finds that the scope of financial authorities in developing countries to reduce remittance fees is limited because a large part of the fees charged to customers are set by financial institutions located in the countries where transactions originate. Cooperation between sending and recipient countries is needed to reduce remittance costs. The survey finds that in several countries money transfer companies are not properly supervised. Given the increasing international concerns with money laundering and terrorism financing issues, it is important that basic registration and reporting requirements are introduced for money transfer companies. Registration and reporting requirements should be designed in such a way that they do not deter the further development of this type of financial institution. Finally, the survey finds that most countries need to establish better mechanisms that would allow them to maximize the developmental effect of remittance inflows. By establishing new savings and investment instruments for remittance recipient households, a larger part of remittance flows might be channeled to finance productive investments, thus fostering economic growth.
The Link Between Information Strategy and Electronic Commerce

Electronic commerce is emerging as an increasingly important way for organizations to reach potential customers. In effect, it moves the workplace to the customer’s site. Its low cost increases its attractiveness. It is now beginning and will probably continue to have a dramatic impact on business into the 21st century (Hornback, 1995).
Challenges to Academic Integrity: Identifying the Factors Associated With the Cheating Chain

This study examined whether seeing other students cheat in examinations and/or knowing students who routinely cheat in examinations associates with other students' cheating behaviour and on their intentions to cheat in the future. We also examined whether cheating in minor and/or major examinations associates with students' intentions to cheat in the future. Our sample included 195 business students enrolled in accounting classes from three universities located in the USA. Our analyses indicated that having cheated in a minor and/or major examination associated with the sum of having observed other students cheating, knowing a student who routinely cheated and social desirability response bias. Our model for students' intentions to cheat in the future included their having cheated in minor and major examinations. We also tested our findings on the data from prior research, which included students from Australia, China, Ireland, Japan and the USA.
Reversed Radial SLE and the Brownian Loop Measure

The Brownian loop measure is a conformally invariant measure on loops in the plane that arises when studying the Schramm–Loewner evolution (SLE). When an SLE curve in a domain evolves from an interior point, it is natural to consider the loops that hit the curve and leave the domain, but their measure is infinite. We show that there is a related normalized quantity that is finite and invariant under Mobius transformations of the plane. We estimate this quantity when the curve is small and the domain simply connected. We then use this estimate to prove a formula for the Radon–Nikodym derivative of reversed radial SLE with respect to whole-plane SLE.
Mechanically bonded macromolecules

Mechanically bonded macromolecules constitute a class of challenging synthetic targets in polymer science. The controllable intramolecular motions of mechanical bonds, in combination with the processability and useful physical and mechanical properties of macromolecules, ultimately ensure their potential for applications in materials science, nanotechnology and medicine. This tutorial review describes the syntheses and properties of a library of diverse mechanically bonded macromolecules, which covers (i) main-chain, side-chain, bridged, and pendant oligo/polycatenanes, (ii) main-chain oligo/polyrotaxanes, (iii) poly[c2]daisy chains, and finally (iv) mechanically interlocked dendrimers. A variety of highly efficient synthetic protocols—including template-directed assembly, step-growth polymerisation, quantitative conjugation, etc.—were employed in the construction of these mechanically interlocked architectures. Some of these structures, i.e., side-chain polycatenanes and poly[c2]daisy chains, undergo controllable molecular switching in a manner similar to their small molecular counterparts. The challenges posed by the syntheses of polycatenanes and polyrotaxanes with high molecular weights are contemplated.
Legislative Bargaining and the Dynamics of Public Investment

We present a legislative bargaining model of the provision of a durable public good over an infinite horizion. In each period, there is a societal endowment which can either be invested in the public good or consumed. We characterize the optimal public policy, defined by the time path of investment and consumption. In each period, a legislature with representatives of each of “n” districts bargain over the current period’s endowment for investment in the public good and transfers to each district. We analyze the Markov perfect equilibrium under different voting “q”-rules where “q” is the number of yes votes required for passage. We show that the efficiency of the public policy is increasing in “q” because higher “q” leads to higher investment in the public good and less pork. We examine the theoretical equilibrium predictions by conducting a laboratory experiment with five-person committees that compares three alternative voting rules: unanimity (q=5); majority (q=3); and dictatorship (q=1).
A new concept for cancer therapy: out-competing the aggressor

Cancer expansion depends on host organ conditions that permit growth. Since such microenvironmental nourishment is limited we argue here that an autologous, therapeutically engineered and faster metabolizing cell strain could potentially out-compete native cancer cell populations for available resources which in turn should contain further cancer growth. This hypothesis aims on turning cancer progression, and its microenvironmental dependency, into a therapeutic opportunity. To illustrate our concept, we developed a three-dimensional computational model that allowed us to investigate the growth dynamics of native tumor cells mixed with genetically engineered cells that exhibit a higher proliferation rate. The simulation results confirm in silico efficacy of such therapeutic cells to combating cancer cells on site in that they can indeed control tumor growth once their proliferation rate exceeds a certain level. While intriguing from a theoretical perspective, this bold, innovative ecology-driven concept bears some significant challenges that warrant critical discussion in the community for further refinement.
Practical Synthesis of Enantiomerically Pure β2-Amino Acids via Proline-Catalyzed Diastereoselective Aminomethylation of Aldehydes

Proline-catalyzed diastereoselective aminomethylation of aldehydes using a chiral iminium ion, generated from a readily prepared precursor, provides alpha-substituted-beta-amino aldehydes with 85:15 to 90:10 dr. The alpha-substituted-beta-amino aldehydes can be reduced to beta-substituted-gamma-amino alcohols, the major diastereomer of which can be isolated via crystallization or column chromatography. The amino alcohols are efficiently transformed to protected beta2-amino acids, which are valuable building blocks for beta-peptides, natural products, and other interesting molecules. Because conditions for the aminomethylation and subsequent reactions are mild, beta2-amino acid derivatives with protected functional groups in the side chain, such as beta2-homoglutamic acid, beta2-homotyrosine, and beta2-homolysine, can be prepared in this way. The synthetic route is short, and purifications are simple; therefore, this method enables the preparation of protected beta2-amino acids in useful quantities.
A new model of plan recognition

We present a new abductive, probabilistic theory of plan recognition. This model differs from previous theories in being centered around a model of plan execution: most previous methods have been based on plans as formal objects or on rules describing the recognition process. We show that our new model accounts for phenomena omitted from most previous plan recognition theories: notably the cumulative effect of a sequence of observations of partially-ordered, interleaved plans and the effect of context on plan adoption. The model also supports inferences about the evolution of plan execution in situations where another agent intervenes in plan execution. This facility provides support for using plan recognition to build systems that will intelligently assist a user.
Scalable packet classification

Packet classification is important for applications such as firewalls, intrusion detection, and differentiated services. Existing algorithms for packet classification reported in the literature scale poorly in either time or space as filter databases grow in size. Hardware solutions such as TCAMs do not scale to large classifiers. However, even for large classifiers (say, 100 000 rules), any packet is likely to match a few (say, 10) rules. This paper seeks to exploit this observation to produce a scalable packet classification scheme called Aggregated Bit Vector (ABV). It takes the bit vector search algorithm (BV) described in Lakshman and Stidialis, 1998 (which takes linear time) and adds two new ideas, recursive aggregation of bit maps and filter rearrangement, to create ABV (which can take logarithmic time for many databases). We show that ABV outperforms BV by an order of magnitude using simulations on both industrial firewall databases and synthetically generated databases.
The Likelihood Encoder for Lossy Compression

A likelihood encoder is studied in the context of lossy source compression. The analysis of the likelihood encoder is based on the soft-covering lemma. It is demonstrated that the use of a likelihood encoder together with the soft-covering lemma yields simple achievability proofs for classical source coding problems. The cases of the point-to-point rate-distortion function, the rate-distortion function with side information at the decoder (i.e., the Wyner–Ziv problem), and the multi-terminal source coding inner bound (i.e., the Berger–Tung problem) are examined in this paper. Furthermore, a non-asymptotic analysis is used for the point-to-point case to examine the upper bound on the excess distortion provided by this method. The likelihood encoder is also related to a recent alternative technique using the properties of random binning.
Why are children in the same family so different from one another

Summary One of the most important findings that has emerged from human behavioral genetics involves the environment rather than heredity, providing the best available evidence for the importance of environmental influences on personality, psychopathology, and cognition. The research also converges on the remarkable conclusion that these environmental influences make two children in the same family as different from one another as are pairs of children selected randomly from the population. The theme of the target article is that environmental differences between children in the same family (called “nonshared environment”) represent the major source of environmental variance for personality, psychopathology, and cognitive abilities. One example of the evidence that supports this conclusion involves correlations for pairs of adopted children reared in the same family from early in life. Because these children share family environment but not heredity, their correlation directly estimates the importance of shared family environment. For most psychological characteristics, correlations for adoptive “siblings” hover near zero, which implies that the relevant environmental influences are not shared by children in the same family. Although it has been thought that cognitive abilities represent an exception to this rule, recent data suggest that environmental variance that affects IQ is also of the nonshared variety after adolescence. The article has three goals: (1) To describe quantitative genetic methods and research that lead to the conclusion that nonshared environment is responsible for most environmental variation relevant to psychological development, (2) to discuss specific nonshared environmental influences that have been studied to date, and (3) to consider relationships between nonshared environmental influences and behavioral differences between children in the same family. The reason for presenting this article in BBS is to draw attention to the far-reaching implications of finding that psychologically relevant environmental influences make children in a family different from, not similar to, one another.
A MODEL OF ENTRY-EXIT DECISIONS AND CAPACITY CHOICE UNDER DEMAND UNCERTAINTY

Abstract Many investment decisions of agribusiness firms, such as when to invest in an emerging market or whether to expand the capacity of the firm, involve irreversible investment and uncertainty about demand, cost or competition. This paper uses an option-value model to examine the factors affecting an agribusiness firm’s decision whether and how much to invest in an emerging market under demand uncertainty. Demand uncertainty and irreversibility of investment make investment less desirable than the net present value (NPV) rule indicates. The inactive firm is more reluctant to enter the market when it takes into account demand uncertainty because it preserves the opportunity of making a better investment later. The active firm is more reluctant to abandon the investment because there is an option value of keeping the operation alive. There is a greater distance between the entry and exit thresholds under the option-value approach than under the NPV rule due to demand uncertainty. The results have implications for agribusiness decision-making.
Risk Attitudes of Children and Adults: Choices Over Small and Large Probability Gains and Losses

In this paper we examine how risk attitudes change with age. We present participants from age 5 to 64 with choices between simple gambles and the expected value of the gambles. The gambles are over both gains and losses, and vary in the probability of the non-zero payoff. Surprisingly, we find that many participants are risk seeking when faced with high-probability prospects over gains and risk averse when faced with small-probability prospects. Over losses we find the exact opposite. Children’s choices are consistent with the underweighting of low-probability events and the overweighting of high-probability ones. This tendency diminishes with age, and on average adults appear to use the objective probability when evaluating risky prospects.
Wound bed score and its correlation with healing of chronic wounds

ABSTRACT: Adequate wound bed preparation is essential for healing of leg ulcers, and consists of controlling exudate and edema, decreasing the bacterial burden, promoting healthy granulation tissue, and removing necrotic tissue. Currently, there is no classification system for wound bed preparation that has predictive value. Based on past work and the authors’ experience, we have now developed and tested a new classification system that scores the following parameters: healing edges (wound edge effect), presence of eschar, greatest wound depth/granulation tissue, amount of exudate amount, edema, peri-wound dermatitis, peri-wound callus and or fibrosis, and a pink/red wound bed. Each parameter receives a score from 0 (worst score) to 2 (best score), and all the parameter scores are added for a total score. Each wound can have a maximum score of 16 (the best score possible), to a minimum score of 0 (the worst score possible). We used this wound bed score (WBS) system in a study of 177 patients with venous ulcers who had been prospectively treated with and randomized to either conventional therapy (compression alone) or a living bilayered skin construct (BSC). We evaluated serial photographs at baseline to determine whether the results would be predictive of complete wound closure and could validate the WBS. We found that wounds that ultimately achieved full closure had a statistically significant higher WBS than those that did not heal (p = 0.0012). This was also true when separating wounds by treatment modality: standard therapy (p = 0.044) and treatment with a BSC (p = 0.011). When dividing the WBS in the following quartile groups: scores 4–10, 10–12, 12–13, and 13–16, the percentage of healed wounds correlated with the WBS (p = 0.0008). For all wounds, a one unit increase in total WBS resulted on average in a 22.8% increase in odds of healing (OR = 1.228). This WBS seems to have validity in predicting complete wound closure in wounds treated with either standard therapy or advanced modalities, such as BSC. If confirmed and widely adopted in this and other types of wounds, it could be a useful tool in both the clinical and research setting.
Commutative ring objects in pro-categories and generalized Moore spectra

We develop a rigidity criterion to show that in simplicial model categories with a compatible symmetric monoidal structure, operad structures can be automatically lifted along certain maps. This is applied to obtain an unpublished result of M J Hopkins that certain towers of generalized Moore spectra, closely related to the K.n/‐local sphere, are E1 ‐algebras in the category of pro-spectra. In addition, we show that Adams resolutions automatically satisfy the above rigidity criterion. In order to carry this out we develop the concept of an operadic model category, whose objects have homotopically tractable endomorphism operads. 55P43, 55U35; 18D20, 18D50, 18G55
Poisson's ratio in cubic materials

Expressions are given for the maximum and minimum values of Poisson’s ratio n for materials with cubic symmetry. Values less than K1 occur if and only if the maximum shear modulus is associated with the cube axis and is at least 25 times the value of the minimum shear modulus. Large values of jnj occur in directions at which the Young modulus is approximately equal to one half of its 111 value. Such directions, by their nature, are very close to 111. Application to data for cubic crystals indicates that certain Indium Thallium alloys simultaneously exhibit Poisson’s ratio less than K1 and greater than C2.
National Banking's Role in U.S. Industrialization, 1850–1900

The passage of the National Banking Acts stabilized the existing financial system and encouraged the entry of 729 banks between 1863 and 1866. These new banks concentrated in the area that would eventually become the Manufacturing Belt. Using a new bank census, the article shows that these changes to the financial system were a major determinant of the geographic distribution of manufacturing and the nation's sudden capital deepening. The entry not only resulted in more manufacturing capital and output at the county level, but also more steam engines and value added at the establishment level.
‘Look like the innocent flower, but be the serpent under’t’: mimicking behaviour of growth-oriented terrorist organizations

This paper examines the interaction between a growth-oriented terrorist organization and an uninformed government based on a two-period signalling game. Combining the signalling game and organizational growth approaches of previous contributions, this paper shows that, if a terrorist group follows a growth strategy, it has an incentive to appear weaker than it is by mimicking the behaviour of a smaller organization. Depending on its beliefs about the extent of the terrorist threat, it can be optimal for a government to spend more on second-period counter-terrorism measures if it is not attacked in the first period than if it were attacked.
Reactive immunization elicits catalytic antibodies for polyester hydrolysis

In the search for biocatalysts for degradation of nonnatural polymers, reactive immunization with haptens 7 and 11 was used to prepare catalytic antibodies capable of cleaving short oligomeric esters, as well as the insoluble polyester 25. These antibodies were found to be highly specific and efficient esterases for oligomers. Triester 24 was preferentially hydrolyzed by an endo-cleavage pathway, however, with a higher molecular weight polymer 25 no site specificity could be observed. Catalytic efficiency of the antibodies towards the insoluble polymer 25 was limited due to physical constraints.
Switch Triggers for Optimal Vibration Reduction Via Resonance Frequency Detuning

For systems subjected to linear frequency sweep excitation, piezoelectric-based resonance frequency detuning provides vibration reduction by altering the stiffness state of the material as it passes through resonance. This vibration reduction technique applies to turbomachinery experiencing changes in rotation speed, for example on spool-up and spool-down. The peak response dynamics are determined by the system’s sweep rate, modal damping ratio, electromechanical coupling coefficient, and, most importantly, the frequency at which the stiffness state is altered. An analytical approach is employed to solve the nondimensional single degree of freedom equation of motion and is scaled to incorporate the altered system frequency following the stiffness state switch. This paper provides an extensive study over a range of sweep rates, damping ratios, and electromechanical coupling coefficients to determine the optimal frequency switch trigger that minimizes the response envelope. This switch trigger is primarily a function of the electromechanical coupling coefficient and the phase of vibration at which the switch occurs. As the coupling coefficient increases, the switch trigger decreases and is approximately linear with the square of this coupling coefficient. Furthermore, as with other state-switching techniques, the optimal frequency switch occurs when the phase of vibration is at the point of maximum displacement, or peak strain energy.© 2014 ASME
The Slave Trade and the Origins of Mistrust in Africa

In a recent study, Nunn (2008) examines the long-term impacts of Africa’s slave trade. He finds that the slave trade, which occurred over a period of more than 400 years, had a significant negative effect on long-term economic development. Although the article arguably identifies a negative causal relationship between the slave trade and income today, the analysis is unable to establish the exact causal mechanisms underlying this reduced-form relationship. In this article, we examine one of the channels through which the slave trade may affect economic development today. Combining contemporary individual-level survey data with historical data on slave shipments by ethnic group, we ask whether the slave trade caused a culture of mistrust to develop within Africa. Initially, slaves were captured primarily through state organized raids and warfare, but as the trade progressed, the environment of ubiquitous insecurity caused individuals to turn on others—including friends and family members—and to kidnap, trick, and sell each other into slavery (Sigismund Wilhelm Koelle 1854; P. E. H. Hair 1965; Charles Piot 1996). We hypothesize that in this environment, a culture of mistrust may have evolved, which may persist to this day. We show that current differences in trust levels within Africa can be traced back to the transatlantic and Indian Ocean slave trades. Combining contemporary individual-level survey data with historical data on slave shipments by ethnic group, we find that individuals whose ancestors were heavily raided during the slave trade are less trusting today. Evidence from a variety of identification strategies suggests that the relationship is causal. Examining causal mechanisms, we show that most of the impact of the slave trade is through factors that are internal to the individual, such as cultural norms, beliefs, and values. (JEL J15, N57, Z13)
Inferences of mix in direct-drive spherical implosions with high uniformity

A large number of diagnostics have been used to study the performance of gas-filled, plastic-shell direct-drive implosions on the 60-beam OMEGA laser system (Boehly T R et al 1997 Opt. Commun. 133 495). These diagnostics allow an estimate of the amount of fuel–pusher mixing in the compressed core. Implosions have primary neutron yields and fuel areal densities that are ∼35% and ∼100% of the predicted one-dimensional values, respectively. A highly constrained model of the core conditions and fuel–shell mix has been developed. It suggests that there is a ‘clean’ fuel region surrounded by a mixed region, with the clean region accounting for ∼70% of the fuel areal density.
Aging and the Questionable Validity of Recognition-Based Exposure Measurement

Growing evidence suggests that basic exposure measures, such as recognition-based items, might not operate identically among older and younger adults. We present two studies relevant to this debate. Study 1 provides experimental confirmation of the recognition decline hypothesis, finding an interaction between age and exposure in predicting recognition memory for an advertisement related to global warming. Study 2 assesses television news project evaluation data to explore whether verbatim detail recognition difficulty explains Study 1 results. The two studies provide complementary evidence, not only illustrating recognition decline among the elderly but also providing careful control of exposure in Study 1 and the use of multiple messages, realistic viewing scenarios, and free recall data in Study 2. Taken together, the studies offer a cautionary tale for campaign evaluators. On a broader theoretical level, the results suggest a fruitful path for communication research focused on the nuanced and potentia...
Impaired cholecystokinin-induced gallbladder emptying incriminated in spontaneous “black” pigment gallstone formation in germfree Swiss Webster mice

“Black” pigment gallstones form in sterile gallbladder bile in the presence of excess bilirubin conjugates (“hyperbilirubinbilia”) from ineffective erythropoiesis, hemolysis, or induced enterohepat...
Multireference alignment using semidefinite programming

The multireference alignment problem consists of estimating a signal from multiple noisy shifted observations. Inspired by existing Unique-Games approximation algorithms, we provide a semidefinite program (SDP) based relaxation which approximates the maximum likelihood estimator (MLE) for the multireference alignment problem. Although we show this MLE problem is Unique-Games hard to approximate within any constant, we observe that our poly-time approximation algorithm for this problem appears to perform quite well in typical instances, outperforming existing methods. In an attempt to explain this behavior we provide stability guarantees for our SDP under a random noise model on the observations. This case is more challenging to analyze than traditional semi-random instances of Unique-Games: the noise model is on vertices of a graph and translates into dependent noise on the edges. Interestingly, we show that if certain positivity constraints in the relaxation are dropped, its solution becomes equivalent to performing phase correlation, a popular method used for pairwise alignment in imaging applications. Finally, we describe how symmetry reduction techniques from matrix representation theory can greatly decrease the computational cost of the SDP considered.
Why Whine about Wining and Dining

Given potential abuse, conflicts of interest, and other issues, why do companies routinely pay for their managers to entertain the managers of other firms and allow their own managers to be so entertained? An answer that such practices facilitate interfirm cooperation is incomplete because it fails to address why companies cannot or do not induce such cooperation directly via their own incentive systems. This article addresses these issues. It shows, inter alia, that even when firms can induce cooperation via their own incentive systems, they will do better obtaining that cooperation via cross-firm entertaining and other favor granting. This remains true even if “entertainment” budgets are subject to corruption, including excessive use or potential embezzlement. Furthermore, the results are wholly independent of any favorable tax treatment such practices may receive. (JEL D82, D86, L14, L24, M52.)
Uniqueness of stationary equilibria in a one-dimensional model of bargaining

Abstract We prove uniqueness of stationary equilibria in a one-dimensional model of bargaining with quadratic utilities, for an arbitrary common discount factor. For general concave utilities, we prove existence and uniqueness of a “minimal” stationary equilibrium and of a “maximal” stationary equilibrium. We provide an example of multiple stationary equilibria with concave (nonquadratic) utilities.
Synthesis of functionalized cannabinoids.

An effective synthesis of tricyclic, nonclassical cannabinoids has been developed on the basis of a cation−olefin cyclization that forms the two nonaromatic rings with the desired stereochemistry in a single step.
Skill Uncertainty, Skill Accumulation, and Occupational Choice

Workers entering the labor market are uncertain about their skill set. Standard human capital theory assumes workers have perfect information about their skills. In this paper, I argue that skill uncertainty can explain one type of worker moves that standard human capital theory cannot: moves between jobs where they perform different kinds of tasks. I consider workers who have a multi-dimensional bundle of labor market skills and begin their careers uncertain about their skill levels. I construct a model that links learning about skills to the tasks performed in jobs: the more intensely a job uses a particular skill, the more the workers learn about their true level of that skill. The model also contains a skill accumulation motive: as workers use a skill they gain additional amounts of it. A simplified version of the model suggests that if skill uncertainty were the dominant force workers would switch between jobs that use skills in different ratios but similar total levels. On the other hand, if skill accumulation were the dominant force they would switch between jobs that use similar ratios of skills but higher total levels. Linking data on workers from the National Longitudinal Study of Youth 1979 with occupational characteristics from the US Department of Labor O*NET database, I show that worker mobility across different task mixes is common and I estimate the model parameters. The current results indicate that skill uncertainty explains approximately 30% of worker mobility across different task ratios.
The polytope of dual degree partitions

Abstract We determine the extreme points and facets of the convex hull of all dual degree partitions of simple graphs on n vertices. (This problem was raised in the Laplace Energy group of the Workshop Spectra of Families of Matrices described by Graphs , Digraphs , and Sign Patterns held at the American Institute of Mathematics Research Conference Center on October 23–27, 2006 [R. Brualdi, Leslie Hogben, Brian Shader, AIM Workshop – Spectra of Families of Matrices Described by Graphs, Digraphs, and Sign Patterns, Final Report: Mathematical Results, November 17, 2006].)
Syntheses of 1-Alkyl-1,2,4-triazoles and the Formation of Quaternary 1-Alkyl-4-polyfluoroalkyl-1,2,4-triazolium Salts Leading to Ionic Liquids

1,2,4-Triazole was alkylated (alkyl = methyl, butyl, heptyl, decyl) at N-1 in >90% isolated yields. The resulting 1-alkyl triazoles were quaternized at N-4 in >98% isolated yields using fluorinated alkyl halides with >98% isolated yields, under neat reaction conditions at 100−120 °C to form N1-CH3-N4-(CH2)2CmF2m + 1-triazolium (Taz) iodide (m = 1, 6), N1-C4H9-N4-(CH2)2CmF2m + 1-Taz iodide (m = 1, 4, 6), N1-C7H15-N4-(CH2)2CmF2m + 1-Taz iodide (m = 1, 4, 6), N1-C10H21-N4-(CH2)2CmF2m + 1-Taz iodide (m = 1, 4), and N1-CnH2n + 1-N4-(CH2)2F-Taz bromide (n = 4, 7, 10). Single-crystal X-ray analyses confirmed the structure of [1-CH3-4-CH2CH2CF3-Taz]+I-. It crystallized in the orthorhombic space group Pccn, and the unit cell dimensions were a = 13.8289(9) A, b = 17.3603(11) A, c = 9.0587(6) A (α = β = γ = 90°). Metathesis of these polyfluoroalkyl-substituted triazolium halides with other salts led to the formation of quaternary compounds, some of which comprise ionic liquids, namely, [R(Rf)-Taz]+Y- (Y = NTf2, BF4,...
Monaural speech segregation based on pitch tracking and amplitude modulation

Segregating speech from one monaural recording has proven to be very challenging. Monaural segregation of voiced speech has been studied in previous systems that incorporate auditory scene analysis principles. A major problem for these systems is their inability to deal with the high-frequency part of speech. Psychoacoustic evidence suggests that different perceptual mechanisms are involved in handling resolved and unresolved harmonics. We propose a novel system for voiced speech segregation that segregates resolved and unresolved harmonics differently. For resolved harmonics, the system generates segments based on temporal continuity and cross-channel correlation, and groups them according to their periodicities. For unresolved harmonics, it generates segments based on common amplitude modulation (AM) in addition to temporal continuity and groups them according to AM rates. Underlying the segregation process is a pitch contour that is first estimated from speech segregated according to dominant pitch and then adjusted according to psychoacoustic constraints. Our system is systematically evaluated and compared with pervious systems, and it yields substantially better performance, especially for the high-frequency part of speech.
Saving or stripping rural industry: an analysis of privatization and efficiency in China

Abstract This paper describes the process of privatization of China’s Township Enterprises. Findings from a recent field survey by the authors show how far privatization has proceeded and how it has affected firm performance. The pervasiveness and impact of privatization are readily apparent. The privatization in the mid-1990s was deep and fundamental. More than 50% of local government-owned firms have transferred their shares to the private sector, partially or completely. Privatization is widespread, regardless of what definition we use (share shifting, controlling interest shifting, or complete). Although we do not find any evidence in our descriptive statistics that private and privatized firms outperform government ones, the private sector does appear to be beginning to manage its firms (e.g., labor and inventories) somewhat differently. Our multivariate analysis, however, finds a positive impact of privatization on technical efficiency. Efficiency of China’s rural industries, including agro-industrial firms, would rise, if township enterprises privatized. The impact of privatization, however, does not occur immediately. Transitional costs apparently reduce private firm efficiency in the year that firms are being privatized. It is possible to surmise that as privatized firms complete their ownership transition and continue to learn how to adapt to China’s business environment that the gains could rise further. However, we cannot say if the gain in efficiency is enough to make rural industries competitive in the future.
The preparation of functionalized amines and amides using benzotriazole derivatives and organozinc reagents

Abstract Secondary and tertiary amines 6 are conveniently prepared in good yields by reacting organozinc halides with adducts 4, which are derived from the corresponding amines, aldehydes and benzotriazole. The use of organozinc reagents enables the introduction of nitro, cyano or ester functionalities into amine mainframes. This methodology was also used to prepare functionalized amides 8.
Precision X-Ray Timing of RX J0806.3+1527 with Chandra: Evidence for Gravitational Radiation from an Ultracompact Binary

RX J0806.3+1527 is a candidate double degenerate binary with possibly the shortest known orbital period. The source shows an approximately equal to 100% X-ray intensity modulation at the putative orbital frequency of 3.11 mHz (321.5 s). If the system is a detached, ultracompact binary gravitational radiation should drive spin-up with a magnitude of nu(sup dot) approximately 10(exp -16) Hz per second. Efforts to constrain the X-ray frequency evolution to date have met with mixed success, principally due to the sparseness of earlier observations. Here we describe the results of the first phase coherent X-ray monitoring campaign on RX J0806.3+1527 with Chandra. We obtained a total of 70 ksec of exposure in 6 epochs logarithmically spaced over 320 days. With these data we conclusively show that the X-ray frequency is increasing at a rate of 3.77 plus or minus 0.8 x 10(exp -16) Hz per second. Using the ephemeris derived from the new data we are able to phase up all the earlier Chandra and ROSAT data and show they are consistent with a constant nu(sup dot) = 3.63 plus or minus 0.06 x 10(exp -16) Hz per second over the past decade. This value appears consistent with that recently derived by Israel et al. largely from monitoring of the optical modulation, and is in rough agreement with the solutions reported initially by Hakala et al., based on ground-based optical observations. The large and stable nu(sup dot) over a decade is consistent with gravitational radiation losses driving the evolution. An intermediate polar (IP) scenario where the observed X-ray period is the spin period of an accreting white dwarf appears less tenable because the observed nu(sup dot) requires an m(sup dot) approximately equal to 4 x 10 (exp -8) solar mass yr(sup -l), that is much larger than that inferred from the observed X-ray luminosity (although this depends on the uncertain distance and bolometric corrections), and it is difficult to drive such a high m(sup dot) in a binary system with parameters consistent with all the multiwavelength data. If the ultracompact scenario is correct, then the X-ray flux cannot be powered by stable accretion which would drive the components apart, suggesting a new type of energy source (perhaps electromagnetic) may power the X-ray flux.
Estimating the effects of school finance reform: a framework for a federalist system

Abstract This paper models the effect of increased state involvement in school funding on education spending levels. Unlike previous studies that have assumed perfect sorting of voters into districts by income, this analysis assumes demand sorting. I, thus, am able to utilize the true distribution of wealth across districts to estimate tax price changes and to predict changes in district spending levels in response to a change in financing rules. I look specifically at three types of state funding programs: those in which districts receive a set per pupil grant from the state and are not allowed to raise additional funds, those in which districts are allowed to raise unlimited additional funds, and those in which this supplementation is capped. Both the model and the subsequent simulations indicate that the ostensible benefits of a system with unlimited local supplementation – that it retains much local control over funding decisions on the margin while insuring an ‘adequate’ level of financing for all districts – may not be sustainable because high wealth districts have no incentive to support state funding. Additionally, a system with no local supplementation may be politically difficult because it forces many voters far from their preferred spending levels. Capped supplementation provides a balance between local control and spending equity.