cssi/SciSciGPT-SciSciNet huggingface dataset:
Associative search network: A reinforcement learning associative memory

An associative memory system is presented which does not require a "teacher" to provide the desired associations. For each input key it conducts a search for the output pattern which optimizes an external payoff or reinforcement signal. The associative search network (ASN) combines pattern recognition and function optimization capabilities in a simple and effective way. We define the associative search problem, discuss conditions under which the associative search network is capable of solving it, and present results from computer simulations. The synthesis of sensory-motor control surfaces is discussed as an example of the associative search problem.
Some approximation theorems

The general theme of this note is illustrated by the following theorem:Theorem 1.Suppose K is a compact set in the complex plane and 0belongs to the boundary ∂K. Let A(K) denote the space of all functions f on K such that f is holo morphic in a neighborhood of K and f(0) = 0.Also for any givenpositive integer m, let A(m, K) denote the space of all f such that f is holomorphic in a neighborhood of K and f(0) =f′(0) = ... =f(m)(0) = 0.Then A(m, K) is dense in A(K) under the supre mum norm on K provided that there exists a sector W = reiθ; 0≤r≤ δ,α≤ θ≤ βsuch that W ∩ K = 0. (This is the well- known Poincare’s external cone condition). We present various generalizations of this result in the context of higher dimensions replacing holomorphic with harmonic.
Factorizations of some weighted spanning tree enumerators

We give factorizations for weighted spanning tree enumerators of Cartesian products of complete graphs, keeping track of fine weights related to degree sequences and edge directions. Our methods combine Kirchhoff's Matrix-Tree Theorem with the technique of identification of factors.
Modeling defect-feature interactions in the presence of aberrations

Programmed defects about 0.4 ?/NA in size are introduced in strong phase-shifting masks to produce exposure-sensitive printable artifacts for measuring lens aberrations. The programmed defects add interferrometric-like reference electric fields that coherently interact with the side-lobes of aberration sensitive pattern layouts to produce artifacts. The artifacts are separate but adjacent printed defects. The patterns are suitable for rapid reading by automatic wafer inspection equipment and directly indicate the levels of specific Zemike aberrations. High sensitivity to 0.01 X and good orthogonality with 12% confounding are possible for coma and trifoil. Results for even aberrations such as focus, astigmatism and spherical 3rd order are poor for 180° phase defect-probes but warrant further investigation with 90° phase.
Extremal limits and black hole entropy

Taking the extremal limit of a non-extremal Reissner-Nordstrom black hole (by externally varying the mass or charge), the region between the inner and outer event horizons experiences an interesting fate — while this region is absent in the extremal case, it does not disappear in the extremal limit but rather approaches a patch of AdS_2 × S^2. In other words, the approach to extremality is not continuous, as the non-extremal Reissner-Nordstrom solution splits into two spacetimes at extremality: an extremal black hole and a disconnected AdS space. We suggest that the unusual nature of this limit may help in understanding the entropy of extremal black holes.
On synchronization of coupled Hopf-Kuramoto oscillators with phase delays

This paper presents new methods and results on synchronization of coupled Hopf nonlinear oscillators, which are commonly used as the dynamic model of engineered central pattern generators (CPGs). On balanced graphs, any positive coupling gain is proven to induce almost global asymptotic synchronization, and a threshold value for truly global exponential synchronization is also computed. Furthermore, a hierarchical connection between coupled Hopf oscillators and Kuramoto oscillators is identified. Finally, a new result on the synchronization of Kuramoto oscillators with arbitrary time-varying heterogeneous frequencies and delays is derived.
Universal coverage in the United States: Lessons from experience of the 20th century

Both the rising numbers of uninsured Americans and the recent presidential election have put the issue of universal health insurance coverage back on the national agenda. Lack of health insurance is a major barrier to care for 44 million Americans, and lack of high-quality, comprehensive insurance is a barrier to millions more. Universal coverage is one of the best ways to ensure that all Americans have equitable access to quality care, and it also contributes to the financial stability of health care providers, especially those in the urban safety net. A wide variety of ideas to expand health care coverage were proposed, and in some cases enacted, during the last century. At the beginning of the 21st century, the American health care system is made up of varied elements, ranging from employer-sponsored health insurance for the majority of working-age adults to the public Medicare program for the elderly. While this patchwork system leaves many Americans without health insurance, it also creates many different ways to expand coverage, including various options in both the private and public sectors. By understanding howthe current health care system developed, howthe various proposals for universal health coverage gained and lost political and public support, and the pros and cons of the various alternatives available to expand coverage, we create a solid base from which to solve the problem of the uninsured in the 21st century.
Multiple chemical sensitivities

In 1987 Cullen’ proposed the term multiple chemical sensitivities to define a condition that he described as “An acquired disorder characterized by recurrent symptoms, referable to multiple organ systems, occurring in response to demonstrable exposure to chemically unrelated compounds at doses far below those established in the general population to cause harmful effects. No single widely accepted test of physiologic function can be shown to correlate with symptoms.” “Multiple chemical sensitivities” is a renaming of a condition previously known as “environmental illness.“’ The newer term first appeared in a published volume that contained 12 chapters written by different physicians with widely differing views of “environmental illness.“’ The total allergy syndrome, twentieth century disease, cerebral allergy, and chemically induced immune dysregulation are a few of the many other names used to describe the same condition3 The concept of “multiple chemical sensitivities” as a physical illness is central to the alternative form of medical practice known as clinical ecology.“, 5 During the past 40 years the small group of physicians who practice clinical ecology have brought forth the idea that some persons are made sick because of the toxic effects of environmental synthetilc chemicals. These persons have polysystemic, multiple symptomatic complaints without any objective evidence of physical disease.6 In most c.ases the symptoms are attributed to ordinary low-level exposure to chemicals that are generally considered safe and do not appear to affect the rest of the population. In some cases the disease is attributed to a particular exposure incident, and in other cases it is attributed to long-term accumulated exposure. Clinical ecologists often use ,the concept of multiple chemical sensitivities to explain several otherwise well-defined diseases, particularly autoimmune and aller-
Never to be Forgotten: The Tale of Women Spies During the Civil War

Wall provides an overview of the lives of women, who worked as spies, during the Civil War. The paper specifically covers the stories of four women, Belle Boyd, Elizabeth Van Lew, Loreta Janeta Velazquez, and Sarah Emma Edmonds. Each of these women's experiences during the war were unique to them, but at the same time similar. The paper goes into detail explaining how all of the women were committed to their cause, held a degree of power in the war, and their fates after the war were eerily similar regardless of which side they were on. The evidence used to explain the crucial work these women did and how they were committed, had power, and how their fates were similar is heavily primary documents. The documents include the women’s journals and writings after and during the war and newspaper articles during and after the war. By using these sources evidence is found to support the case that even though the women were on different sides during the conflict they had a lot of similar experiences.
Efficient Allocation of Hierarchically-Decomposable Tasks in a Sensor Web Contract Net

In large, distributed systems, such as a sensor web, allocating resources to tasks that span multiple providers presents significant challenges. Individual subtasks associated with a task could potentially be assigned to a number of agents (e.g., when there is overlap in sensor or data processing capability among constituent sensor networks). This problem is further compounded by the dynamic nature of a sensor web, in which both desired tasks and resource availability change with time and environmental conditions. This paper presents a novel variation of the contract net protocol (CNP) for subtask allocation, which employs brokers to limit communication overhead in a two-phase CNP and aggregate domain information from groups of agents. Experimental results using this subtask allocation approach verify its efficiency and scalability. These results also suggest specific refinements and appropriate parameters for a variety of system configurations and operating conditions in sensor webs and other large multi-agent systems.
Forming the First Stars in the Universe: The Fragmentation of Primordial Gas.

In order to constrain the initial mass function of the first generation of stars (Population III), we investigate the fragmentation properties of metal-free gas in the context of a hierarchical model of structure formation. We investigate the evolution of an isolated 3 σ peak of mass 2 × 106 M☉ that collapses at zcoll 30 using smoothed particle hydrodynamics. We find that the gas dissipatively settles into a rotationally supported disk that has a very filamentary morphology. The gas in these filaments is Jeans unstable with MJ ~ 103 M☉. Fragmentation leads to the formation of high-density (n > 108 cm-3) clumps that subsequently grow in mass by accreting the surrounding gas and by merging with other clumps up to masses of ~104 M☉. This suggests that the very first stars were rather massive. We explore the complex dynamics of the merging and tidal disruption of these clumps by following their evolution over a few dynamical times.
The Dendrimer Effect in Homogeneous Catalysis

The immobilization of catalytic groups onto a dendritic support either at the core or at the periphery gives rise to unique properties that affect rates of reaction, substrate activation or selectivity, etc. When advantageous, these properties can be classified as a positive dendrimer effect. Positive dendrimer effects can arise from site isolation, transition state stabilization and/or dielectric effects in the case of core-modified dendrimers, while peripherally modified dendrimers usually benefit from steric crowding or cooperativity for catalytic residues confined to the surface of the polymer. In this review, the appearance of positive dendrimer effects from the literature will be highlighted as well as prospects for future work in the field.
Results With the Neutron Scatter Camera

We describe the design, calibration, and measurements made with the neutron scatter camera. Neutron scatter camera design allows for the determination of the direction and energy of incident neutrons by measuring the position, recoil energy, and time-of-flight (TOF) between elastic scatters in two liquid scintillator cells. The detector response and sensitive energy range (0.5-10 MeV) has been determined by detailed calibrations using a 252Cf neutron source over its field of view (FOV). We present results from several recent deployments. In a laboratory study we detected a 252Cf neutron source at a stand off distance of 30 m. A hidden neutron source was detected inside a large ocean tanker. We measured the integral flux density, differential energy distribution and angular distribution of cosmic neutron background in the fission energy range 0.5-10 MeV at Alameda, CA (sea level), Livermore, CA (174 m), Albuquerque, NM (1615 m) and Fenton Hill, NM (2630 m). The neutron backgrounds are relatively low, and non-isotropic. The camera has been ruggedized, deployed to various locations and has performed various measurements successfully. Our results show fast neutron imaging could be a useful tool for the detection of special nuclear material (SNM).
Stereoselective Mannich Reaction of S‐Phenyl Thioesters Catalyzed by Bifunctional Organocatalysts

S-phenylthioesters undergo an efficient stereoselective addition reaction to N-Tosylaldimines in the presence of a bifunctional organocatalyst.
Speed, power, area, and latency tradeoffs in adaptive FIR filtering for PRML read channels

In this paper, we describe area and power reduction techniques for a low-latency adaptive finite-impulse response filter for magnetic recording read channel applications. Various techniques are used to reduce area and power dissipation while speed and latency remain as the main performance criteria for the target application. The proposed parallel transposed direct form architecture operates on real-time input data samples and employs a fast, low-area multiplier based on selection of radix-8 premultiplied coefficients in conjunction with one-hot encoded bus leading to a very compact layout and reduced power dissipation. Area, speed, and power comparisons with other low-power implementation options are also shown. The proposed filter has been fabricated using a 0.18-/spl mu/m L-effective CMOS technology and operates at 550 MSamples/s. Trading off filter latency to improve speed is also discussed.
A Lunar Electromagnetic Launch System for In Situ Resource Utilization

Future human exploration of the moon will require the development of capabilities for in situ resource utilization. Transport of lunar-derived commodities such as fuel and oxygen to orbiting resource depots has been proposed to enable refueling landers or other vehicles. A lunar electromagnetic launch (LEML) system could be an effective means of transporting materials as an alternative to nonrenewable chemical-based propulsion systems. An example LEML concept is presented based on previous studies, existing electromagnetic launch technologies, and the National Aeronautics and Space Administration's human exploration architecture. A preliminary assessment of the cost versus benefit of such a system is also offered; the conclusion, however, is not as favorable for LEML as originally suggested.
A mathematical model on the rupture of intracranial aneurysms

We constructed and discussed a mathematical model on the rupture of intracranial aneurysms using the concept of daughter aneurysm, a bleb growing out of the weaker part of the aneurysm wall. The rupture risk was found to be a function of the geometry of the daughter aneurysm as well as the radius of the main aneurysm. Our model is in good agreement with the simulation by Steiger (1990). It was suggested that rupture occurs when the stress of the daughter aneurysm reaches that of the parent aneurysm. We also modeled the dynamic development of the daughter aneurysm for various orifice sizes and showed that rupture index first decreases, followed by continuous increase. Rupture occurs sooner for larger daughter aneurysm orifices.
Mechanical Alignment of Suprathermal Paramagnetic Cosmic-Dust Granules: The Cross Section Mechanism

We develop a comprehensive quantitative description of the cross section mechanism discovered by Lazarian. This is one of the processes that determine grain orientation in clouds of suprathermal cosmic dust. The mechanism manifests itself when an ensemble of suprathermal paramagnetic granules is placed in a magnetic field and is subject to ultrasonic gas bombardment. The mechanism yields dust alignment whose efficiency depends on two factors: the geometric shape of the granules and the angle Φ between the magnetic line and the gas flow. We calculate the quantitative measure of this alignment and study its dependence on the said factors. It turns out that, irrelevant of the grain shape, the action of a flux does not lead to alignment if Φ = arccos(1/).
Adaptively secure garbling with applications to one-time programs and secure outsourcing

Standard constructions of garbled circuits provide only static security, meaning the input x is not allowed to depend on the garbled circuit F. But some applications--notably one-time programs (Goldwasser, Kalai, and Rothblum 2008) and secure outsourcing (Gennaro, Gentry, Parno 2010)--need adaptive security, where x may depend on F. We identify gaps in proofs from these papers with regard to adaptive security and suggest the need of a better abstraction boundary. To this end we investigate the adaptive security of garbling schemes, an abstraction of Yao's garbled-circuit technique that we recently introduced (Bellare, Hoang, Rogaway 2012). Building on that framework, we give definitions encompassing privacy, authenticity, and obliviousness, with either coarse-grained or fine-grained adaptivity. We show how adaptively secure garbling schemes support simple solutions for one-time programs and secure outsourcing, with privacy being the goal in the first case and obliviousness and authenticity the goal in the second. We give transforms that promote static-secure garbling schemes to adaptive-secure ones. Our work advances the thesis that conceptualizing garbling schemes as a first-class cryptographic primitive can simplify, unify, or improve treatments for higher-level protocols.
An exploratory study of recreational drug use and nutrition-related behaviors and attitudes among adolescents

This study examined drug use and eating behaviors among adolescents. The data were collected by phone interviews from 401 northern Nevadan students in grades seven to twelve. Students were divided for comparison into three groups according to their involvement with drugs: Abstainers, conventional users, and high-risk users. Analyses indicated that high-risk users less frequently ate lunch, meals at home, and with their families, and ate more often at convenience stores, fast food restaurants, and with friends. In addition, female high-risk users had significantly more negative perceptions regarding their food choices than the other female groups, and were more concerned with dieting than their high-risk using male peers. Male and female high-risk users believed that their drug use affected their eating habits. Implications for prevention programming and future research are discussed.
SEPARABLE TERM STRUCTURES AND THE MAXIMAL DEGREE PROBLEM

This paper discusses separable term structure diffusion models in an arbitrage-free environment. Using general consistency results we exploit the interplay between the diffusion coefficients and the functions determining the forward curve. We introduce the particular class of polynomial term structure models. We formulate the appropriate conditions under which the diffusion for a quadratic term structure model is necessarily an Ornstein-Uhlenbeck type process. Finally, we explore the maximal degree problem and show that basically any consistent polynomial term structure model is of degree two or less.
Lazy Transformation-Based Learning

We introduce a significant improvement for a relatively new machine learning method called Transformation-Based Learning. By applying a Monte Carlo strategy to randomly sample from the space of rules, rather than exhaustively analyzing all possible rules, we drastically reduce the memory and time costs of the algorithm, without compromising accuracy on unseen data. This enables Transformation-Based Learning to apply to a wider range of domains, as it can effectively consider a larger number of different features and feature interactions in the data. In addition, the Monte Carlo improvement decreases the labor demands on the human developer, who no longer needs to develop a minimal set of rule templates to maintain tractability.
Flight Mechanics of a Novel Guided Spin-Stabilized Projectile Concept

Precision-guided munitions are of interest to the Army as a means of both reducing collateral damage and increasing the chance of desired effect with the first round fired. Many technical barriers ...
Ductile tearing resistance of metal sheets

Abstract The concept of R -curves has been adopted to characterise stable crack extension and predict residual strength of thin-walled structures particularly in the aircraft industry. The present contribution uses results of FE simulations of crack extension in panels by the cohesive model to validate analytical procedures for determining J -integral values at large crack extension from measurable quantities, namely the force vs. displacement records. The numerically determined J -integral is taken as the benchmark for the outcome of the analytical formulas. The geometry dependence of J and CTOD based R -curves is investigated and alternative concepts like CTOA and dissipation rate at crack extension are discussed.
Gibbs rapidly samples colorings of G(n, d/n)

Gibbs sampling also known as Glauber dynamics is a popular technique for sampling high dimensional distributions defined on graphs. Of special interest is the behavior of Gibbs sampling on the Erdýos-Renyi random graph G(n,d/n), where each edge is chosen independently with probability d/n and d is fixed. While the average degree in G(n,d/n) is d(1 − o(1)), it contains many nodes of degree of order (logn)/(loglogn). The existence of nodes of almost logarithmic degrees implies that for many natural distributions defined on G(n,d/n) such as uniform coloring (with a constant number of colors) or the Ising model at any fixed inverse temperature β, the mixing time of Gibbs sampling is at least n 1+�( 1/loglogn) with high probability. High degree nodes pose a technical challenge in proving polynomial time mixing of the dynamics for many models including coloring. Almost all known sufficient conditions in terms of number of colors needed for rapid mixing of Gibbs samplers are stated in terms of the maximum degree of the underlying graph. In this work we consider sampling q-colorings and show that for every d 1 where the number of colors does not depend on n. They also provide a rare example where one can prove a polynomial time mixing of Gibbs sampler in a situation where the actual mixing
Salt, Salt Sensitivity, and the Endothelium A Pathway to Discovery of Molecular Mechanisms

See related article, pp 951–956 This issue of Hypertension contains a report of molecular mechanisms transducing dietary salt intake1 that may have broad clinical relevance. These molecular mechanisms are complex, but to begin to understand this study we have to understand the importance of dietary salt intake and salt sensitivity. This background will be discussed in some detail before discussing the molecular mechanisms. Although cohort studies have called into question the role of dietary salt intake in causing hypertension,2 cause and effect relationships are most convincing when demonstrated using randomized clinical trials. It would be unethical to perform a randomized clinical trial in which the dietary intake of salt (sodium chloride) is increased for years in humans to observe an increase in blood pressure. However, such an experiment in primates has been performed by Denton et al,3 who studied in Gabon, Africa, 26 chimpanzees. Chimpanzees have a native diet that is vegetarian and is very high in potassium content. The baseline sodium intake in these primates was only 6 mEq/d; in contrast, that of K was 235 mEq/d. Blood pressure was measured in the 26 animals for 1 year. Subsequently, among half the animals, increasing amounts of salt (in increments of 5 g/d sodium) were added to a diet to a steady-state level of 15 g/d. This dietary intake was maintained for 16 months. After this period of dietary supplementation, the diet was switched to baseline and observations made for another 6 months. A dose–response relationship between salt supplementation and blood pressure increment was seen. With 15 g/d sodium supplementation for 67 weeks, the change from baseline in blood pressure was 33/10 mm Hg. In comparison, 5 g/d sodium supplementation for 19 weeks provoked blood pressure change of 12/0 mm Hg. Notably, plasma renin activity was reduced with salt …
When snacks become meals: How hunger and environmental cues bias food intake

Background: While environmental and situational cues influence food intake, it is not always clear how they do so. We examine whether participants consume more when an eating occasion is associated with meal cues than with snack cues. We expect their perception of the type of eating occasion to mediate the amount of food they eat. In addition, we expect the effect of those cues on food intake to be strongest among those who are hungry. Methods: One-hundred and twenty-two undergraduates (75 men, 47 women; mean BMI = 22.8, SD = 3.38) were randomly assigned to two experimental conditions in which they were offered foods such as quesadillas and chicken wings in an environment that was associated with either meal cues (ceramic plates, glasses, silverware, and cloth napkins at a table), or snack cues (paper plates and napkins, plastic cups, and no utensils). After participants finished eating, they were asked to complete a questionnaire that assessed their hunger, satiety, perception of the foods, and included demographic and anthropometric questions. In addition, participants’ total food intake was recorded. Results: Participants who were in the presence of meal-related cues ate 27.9% more calories than those surrounded with snack cues (416 versus 532 calories). The amount participants ate was partially mediated by whether they perceived the eating occasion to be a meal or a snack. In addition, the effect of the environmental cues on intake was most pronounced among participants who were hungry. Conclusions: The present study demonstrated that environmental and situational cues associated with an eating occasion could influence overall food intake. People were more likely to eat foods when they were associated with meal cues. Importantly, the present study reveals that the effect of these cues is uniquely intertwined with cognition and motivation. First, people were more likely to eat ambiguous foods when they perceived them as a meal rather than a snack. Second, the effect of the environmental cues on intake was only observed among those who were hungry.
The dynamics of ownership of durable goods in Bulgaria : from economic crisis to EU membership

The paper uses repeated cross-sections of Bulgaria's household survey data (1995, 1997, 2001, and 2003) and a comparable list of durable goods to investigate the dynamics and distribution of durable goods over time, including during the economic crisis of 1996-1997 and the subsequent period of relatively robust economic growth leading up to European Union membership. It examines the dynamics of the ownership of durable goods by wealth classes, geographic locations, and various ethnic groups, including the Roma. In the aggregate, there was convergence between the poorest and the richest classes in the ownership of durable goods between 1995 and 2003, with the poorest class making a significant gain between 2001 and 2003 after having lost some ground between 1995 and 2001. There was also convergence in the ownership of durable goods between urban and rural residents. However, there appear to be some diverging tendencies between Bulgarians and the minority ethnic groups, particularly in the ownership of relatively more expensive goods such as personal computers and cars.
A novel two-step method to prepare new unsymmetrical cryptands

Abstract A novel two-step method to prepare unsymmetrical cryptands from available diethanolamine, oligoethylene glycol dichloride and other dihalides is reported. A new cryptand with two bridges each containing one methylene unit exhibited a sodium over potassium selectivity of more than 1,000.
Direct computation of the sound from a compressible co-rotating vortex pair

The far-field sound from corotating vortices is computed by direct computation of the unsteady, compressible Navier-Stokes equations on a computational mesh that extends to two acoustic wavelengths in all directions. The vortices undergo a period of corotation followed by a sudden merger. A 2D version of Moehring's equation is developed and used in conjunction with source terms computed in the simulation to predict the far-field sound. The prediction agrees with the simulation to within 3 percent. Results of far-field pressure fluctuations for an acoustically noncompact case are also presented for which the prediction is 66 percent too high. Results also indicate that the monopole contribution of 'viscous sound' is negligible for this flow.
Searching for the origin of CP violation in Cabibbo-suppressed D-meson decays

studies in the B system have proven to be. The current level of CP violation could be consistent with the Standard Model or, perhaps, contain evidence of new physics. A clean Standard Model prediction of the CP violation in these decays would, of course, be important in understanding these results but hadronic uncertainties make such a prediction difficult. In this paper, we make several suggestions to try to seek the role of new physics. We propose that the hadronic enhancement needed to attribute the observed CP violation in D to two pseudoscalar modes may not operate for inclusive final states, where it is likely that we will see asymmetries at the quark level expectation provided the source is the Standard Model. A simple way to implement this is to search for CP asymmetries in final states containing K and ¯ K but where the sum of their energies is less than the energy of the parent D. This is meant to ensure that the event belongs to an inclusive and not an exclusive sample. We also propose that CP asymmetries may be enhanced in modes where the tree is color suppressed. In particular, the final state ρ 0 ρ 0 is of special interest because it consists of charged pions only and, in addition, it can have C-even P-odd triple product correlations; similarly, Ds → ρ 0 K + and ρ 0 K ∗+ also appear interesting. We also emphasize the use of CPT constraints leading to interesting correlations. We then consider how isospin symmetry can provide observables that are sensitive to certain classes of new physics and are small in the Standard Model. In particular, we discuss using isospin analysis in the decays D → ππ , ρπ, and ρρ as well as in Ds → K ∗ π. We also consider how such analysis may eventually be supplemented by information about the weak phases in D 0 decay. In order to obtain this information experimentally, we consider various methods for preparing an initial state that is a quantum mechanical mixture of D 0 and ¯
Sulfonyl fluorides as privileged warheads in chemical biology

Sulfonyl fluoride electrophiles have found significant utility as reactive probes in chemical biology and molecular pharmacology. As warheads they possess the right balance of biocompatibility (including aqueous stability) and protein reactivity. Their functionality is privileged in this regard as they are known to modify not only reactive serines (resulting in their common use as protease inhibitors), but also context-specific threonine, lysine, tyrosine, cysteine and histidine residues. This review describes the application of sulfonyl fluoride probes across various areas of research and explores new approaches that could further enhance the chemical biology toolkit. We believe that sulfonyl fluoride probes will find greater utility in areas such as covalent enzyme inhibition, target identification and validation, and the mapping of enzyme binding sites, substrates and protein–protein interactions.
A microprogramming design laboratory

Sophisticated design aids are available to help automate microprogram development both for large, complex computers and for microprocessor-based systems. These aids include procedures for source code verification, object code generation, microprogram simulation, and interactive debugging. For various reasons, such aids are generally not well-developed for microprogrammable minicomputers. This paper describes a microprogramming laboratory developed for the Interdata 85 minicomputer which uses both the minicomputer itself as well as the time-sharing and batch facilities of a large computer center. Experience with the laboratory has shown that the facility for interacting with a microprogram is as important as the availability of complete diagnostic information. The argument is made that design automation aids for microprogramming minicomputers could be produced efficiently from standardized assembly and simulation programs.
Comparing multiagent systems research in combinatorial auctions and voting

In a combinatorial auction, a set of items is for sale, and agents can bid on subsets of these items. In a voting setting, the agents decide among a set of alternatives by having each agent rank all the alternatives. Many of the key research issues in these two domains are similar. The aim of this paper is to give a convenient side-by-side comparison that will clarify the relation between the domains, and serve as a guide to future research.
Automatic generation of generalization lemmas for proving properties of tail-recursive definitions

Automatically proving properties of tail-recursive function definitions by induction is known to be challenging. The difficulty arises due to a property of a tail-recursive function definition typically expressed by instantiating the accumulator argument to be a constant only on one side of the property. The application of the induction hypothesis gets blocked in a proof attempt. Following an approach developed by Kapur and Subramaniam, a transformation heuristic is proposed which hypothesizes the other side of property to also have an occurrence of the same constant. Constraints on the transformation are identified which enable a generalization of the constant on both sides with the hope that the generalized conjecture is easier to prove. Conditions are generated from which intermediate lemmas necessary to make a proof attempt to succeed can be speculated. By considering structural properties of recursive definitions, it is possible to identify properties of the functions used in recursive definitions for the conjecture to be valid. The heuristic is demonstrated on well-known tail-recursive definitions on numbers as well as other recursive data structures, including finite lists, finite sequences, finite trees, where a definition is expressed using one recursive call or multiple recursive calls. In case, a given conjecture is not valid because of a possible bug in an implementation (a tail-recursive definition) or a specification (a recursive definition), the heuristic can be often used to generate a counter-example. Conditions under which the heuristic is applicable can be checked easily. The proposed heuristic is likely to be helpful for automatically generating loop invariants as well as in proofs of correctness of properties of programs with respect to their specifications.
Fundamental transmitting properties of carbon nanotube antennas

Fundamental properties of dipole transmitting antennas formed by carbon nanotubes are investigated. Since carbon nanotubes can be grown to centimeter lengths, and since they can be metallic, the properties of carbon nanotubes as antenna elements are of fundamental interest. In this paper, dipole carbon nanotube antennas are investigated via a classical Hallen's-type integral equation, based on a quantum mechanical conductivity. The input impedance, current profile, and efficiency are presented, and the radiation pattern is discussed, as are possible applications.
Temporal Characterization of a Self-Modulated Laser Wakefield

The temporal envelope of plasma density oscillations in the wake of an intense ( $I\ensuremath{\sim}4\ifmmode\times\else\texttimes\fi{}{10}^{18}\mathrm{W}/{\mathrm{cm}}^{2}$, $\ensuremath{\lambda}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1\ensuremath{\mu}\mathrm{m}$) laser pulse (400 fs) is measured using forward Thomson scattering from a copropagating, frequency-doubled probe pulse. The wakefield oscillations in a fully ionized helium plasma ( ${n}_{e}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}3\ifmmode\times\else\texttimes\fi{}{10}^{19}{\mathrm{cm}}^{\ensuremath{-}3}$) are observed to reach maximum amplitude ( $\ensuremath{\delta}{n}_{e}{/n}_{e}\ensuremath{\sim}0.1$) 300 fs after the pump pulse. The wakefield growth ( $3.5{\mathrm{ps}}^{\ensuremath{-}1}$) and decay ( $1.9{\mathrm{ps}}^{\ensuremath{-}1}$) rates are consistent with the forward Raman scattering instability and Landau damping, respectively.
Radius and chirality dependent conformation of polymer molecule at nanotube interface.

Temperature-dependent conformations of linear polymer molecules adsorbed at carbon nanotube (CNT) interfaces are investigated through molecule dynamics simulations. Model polyethylene (PE) molecules are shown to have selective conformations on the CNT surface, controlled by atomic structures of the CNT lattice and geometric coiling energy. PE molecules form entropy driven assembly domains, and their preferred wrapping angles around large radius CNT (40, 40) reflect the molecule configurations with energy minimums on a graphite plane. While PE molecules prefer 0 ° wrapping on small radius armchair CNT (5, 5) predominantly at low temperatures, their configurations are shifted to larger wrapping angle ones on a similar radius zigzag CNT (10, 0). A nematic transformation around 280 K is identified through the Landau-de Gennes theory, with molecule aligning along tube axis in extended conformations.
Safe and efficient tetrazole synthesis in a continuous-flow microreactor.

The process works with a broad substrate scope, requires only a slight excess of NaN3, avoids the use and generation of HN3, and residual NaN3 is quenched in-line with NaNO2.
NGC 2442: Tidal Encounters and the Evolution of Spiral Galaxies

Using imaging Fabry-Perot data, we study the star-forming properties and kinematics of the nearby barred spiral galaxy NGC 2442. The Hα emission is very localized along the strong spiral arms of the galaxy, and shows a marked asymmetry between the sharp, well-defined northern tidal arm and the weaker southern arm. The Hα velocity field appears highly distorted, with a rapidly rotating nuclear component. We find evidence for strong noncircular motions along the northern arm, coincident with the pronounced dust lane and regions of intense star formation. The strong asymmetries, the disturbed velocity field, and the presence of a perturbed companion suggest that we are witnessing a strong kinematic response to a close interaction, which has redistributed the star formation activity throughout the disk of NGC 2442. Dynamical modeling of the NGC 2442 system supports this hypothesis and suggests that the regions of strongest star formation are coincident with strong shocks occurring along the tidally perturbed northern arm. Despite this strong redistribution of the gas on small scales, this galaxy does not show a significant departure from the Tully-Fisher relation, nor does it appear to be experiencing any strong starburst. Moreover, our models predict that in a few times 108 yr, NGC 2442 will have recovered from this first tidal encounter and will experience another passage—and ultimately a merger—in a few gigayears. This merger may provoke stronger, permanent changes in the structural properties of the galaxy, depending on the detailed response of the disk. Given the environment of many disk galaxies, this tidal encounter cycle seems likely to be a normal phase of disk galaxy evolution.
Income segregation from local income taxation when households differ in both preferences and incomes

This paper presents a model of an urban area with local income taxes used to finance a local public good. Households differ in both incomes and their taste for housing. The existence of a segregated equilibrium is shown in a calibrated two-community model assuming single-peaked distributions for both income and housing taste. The equilibrium features income segregation of the population across the communities. The segregation is, however, imperfect: some rich households can be found in poor communities and vice-versa. The calibrated model is able to explain the substantial differences in local income tax levels and average incomes across communities as observed in e.g. Switzerland. The numerical investigation reveals that the ordering of community characteristics critically depends on the substitutability between the public and the private good. The numerical investigation also suggests that taste heterogeneity reduces the distributional effects of local tax differences. The numerical investigation furthermore suggests that the rich community can set lower taxes when it is small.
Hi Clouds Beyond the Galactic Disk

Recent observations in the 21cm line with the Green Bank Telescope have changed our view of the neutral interstellar medium (ISM) in several ways. The new data show that in the inner parts of the Milky Way the disk-halo interface is composed of many discrete HI clouds. The clouds lie in a layer more than one kpc thick and follow Galactic rotation. Their origin and evolution is unknown. In the outer Galaxy, the new data show that the high-velocity cloud Complex H is likely a satellite on a retrograde orbit interacting with some extended component of the MilkyWay’s ISM. These observations place new constraints on models of the ISM and are directly related to the work of Don Cox and Ron Reynolds.
International Organizations Count

This special issue seeks to move forward the development of an empirical research agenda that takes seriously the complexity of how international organizations (IOs) function and the need to study that complexity at all levels of analysis by using robust research tools. We advocate for a broad empirical research approach that molds and sharpens theories about IOs by conducting systematic tests in large-sample environments. Two themes create a common thread throughout this issue. First, shifting the focus from whether IOs matter to how they work requires acknowledgment of the contingency of cause and effect. A second common thread lies in the authors’ treatment of IO membership as an aggregate phenomenon—that is, as a set of institutions and relationships evolving over time and with many members rather than as a single organization.
Ruthenium catalyzed hydroaminoalkylation of isoprene via transfer hydrogenation: byproduct-free prenylation of hydantoins.

The ruthenium catalyst derived from Ru3(CO)12 and triphos [Ph2P(CH2CH2PPh2)2] promotes the direct C–C coupling of isoprene with aryl substituted hydantoins 1a–1f at the diene C4-position to furnish products of n-prenylation 2a–2f. A mechanism involving hydantoin dehydrogenation followed by diene-imine oxidative coupling to furnish a transient aza-ruthencyclopentene is proposed.
Ultrafast Quantum Control in Atoms and Molecules

This chapter introduces concepts in ultrafast coherent control, particularly in the context of strong field atomic and molecular interactions, and interactions with advanced sources of short wavelength radiation. The principle ideas that have driven this field will be introduced, with references to guide the student through the current developments.
From curiosities to commodities: ionic liquids begin the transition

A growing variety of ionic liquids are becoming commercially available, a development that will feed the surge of research using these unorthodox liquids.
Publish and Prosper: The Financial Impact of Publishing by Marketing Faculty

This paper investigates the impact of research productivity on the salaries of marketing faculty members. We examine how the number of articles published in various types of publications affects faculty members' nine-month salary using a sample of three years of information on 298 marketing professors from 33 research-oriented, public universities. Consistent with research conducted in other disciplines, we find a positive impact of publishing on salary. We estimate the individual salary impact for each of the four top-tier journals in marketing, finding that the biggest impact on salary comes from publishing in Marketing Science. Further, we find that publishing in Tier 1 journals in marketing has a bigger salary impact than in Tier 1 journals outside marketing. Finally, we find that faculty and department characteristics also affect salary. For example, being from a higher ranked research university and being a full professor are each associated with higher salary.
Forty years of public economics : a personal perspective

This paper presents a personal perspective on the field of public economics with emphasis on the interplay of theory and applications. In the early 1950s, theoretical developments grew out of practical applications. Yet, few economists succeed in creatively linking theory to real problems and our professional organization fails to promote adequately such contributions. The author also discusses briefly the success of public economics, its fragmentation into subfields, and its relation to macroeconomics. The writing of this paper was prompted by the author's participation in editing a volume of selected papers by William Vickrey, whose work is exemplary of the perspective presented here.
ORGANOSILICON RADICAL-INDUCED CYCLIZATION REACTIONS

Abstract The first examples of selective additions of organosilicon radicals are reported. Trichlorosilyl radicals preferentially attack the carbonyl oxygen atom, while triethylsilyl radicals preferentially attack alkenes. Carbon-carbon bond formation to produce both monocyclic and bridged bicyclic systems is possible.
Quantum Gravity, Dynamical Energy-Momentum Space and Vacuum Energy

We argue that the combination of the principles of quantum theory and general relativity allow for a dynamical energy–momentum space. We discuss the freezing of vacuum energy in such a dynamical energy–momentum space and present a phenomenologically viable seesaw formula for the cosmological constant in this context.
FAST-PPR: scaling personalized pagerank estimation for large graphs

We propose a new algorithm, FAST-PPR, for computing personalized PageRank: given start node s and target node t in a directed graph, and given a threshold δ, it computes the Personalized PageRank π_s(t) from s to t, guaranteeing that the relative error is small as long πs(t) > δ. Existing algorithms for this problem have a running-time of Ω(1/δ in comparison, FAST-PPR has a provable average running-time guarantee of O(√d/δ) (where d is the average in-degree of the graph). This is a significant improvement, since δ is often O(1/n) (where n is the number of nodes) for applications. We also complement the algorithm with an Ω(1/√δ) lower bound for PageRank estimation, showing that the dependence on δ cannot be improved.We perform a detailed empirical study on numerous massive graphs, showing that FAST-PPR dramatically outperforms existing algorithms. For example, on the 2010 Twitter graph with 1.5 billion edges, for target nodes sampled by popularity, FAST-PPR has a 20 factor speedup over the state of the art. Furthermore, an enhanced version of FAST-PPR has a 160 factor speedup on the Twitter graph, and is at least 20 times faster on all our candidate graphs.