cssi/SciSciGPT-SciSciNet huggingface dataset:
The Infinite Mixture of Infinite Gaussian Mixtures

Dirichlet process mixture of Gaussians (DPMG) has been used in the literature for clustering and density estimation problems. However, many real-world data exhibit cluster distributions that cannot be captured by a single Gaussian. Modeling such data sets by DPMG creates several extraneous clusters even when clusters are relatively well-defined. Herein, we present the infinite mixture of infinite Gaussian mixtures (I2GMM) for more flexible modeling of data sets with skewed and multi-modal cluster distributions. Instead of using a single Gaussian for each cluster as in the standard DPMG model, the generative model of I2GMM uses a single DPMG for each cluster. The individual DPMGs are linked together through centering of their base distributions at the atoms of a higher level DP prior. Inference is performed by a collapsed Gibbs sampler that also enables partial parallelization. Experimental results on several artificial and real-world data sets suggest the proposed I2GMM model can predict clusters more accurately than existing variational Bayes and Gibbs sampler versions of DPMG.
Balancing lifetime and classification accuracy of wireless sensor networks

Wireless sensor networks are composed of distributed sensors that can be used for signal detection or classification. The likelihood functions of the hypotheses are often not known in advance, and decision rules have to be learned via supervised learning. A specific learning algorithm is Fisher discriminant analysis (FDA), the classification accuracy of which has been previously studied in the context of wireless sensor networks. Previous work, however, does not take into account the communication protocol or battery lifetime; in this paper we extend existing studies by proposing a model that captures the relationship between battery lifetime and classification accuracy. To do so, we combine the FDA with a model that captures the dynamics of the carrier-sense multiple-access (CSMA) algorithm, the random-access algorithm used to regulate communications in sensor networks. This allows us to study the interaction between the classification accuracy, battery lifetime and effort put towards learning, as well as the impact of the back-off rates of CSMA on the accuracy. We characterize the tradeoff between the length of the training stage and accuracy, and show that accuracy is non-monotone in the back-off rate due to changes in the training sample size and overfitting.
LONG DISTANCE BEHAVIOR OF THE FOUR-DIMENSIONAL NONLINEAR SIGMA MODEL WITH ANOMALY

We study the low energy behavior of the four-dimensional nonlinear sigma model with anomaly using the 2+∊ expansion and renormalization group methods. It is shown that the theory has a non-trivial ir stable fixed point, in addition to the usual trivial fixed point. If pions happen to exist in the non-trivial phase, their propagator would scale at low energies with anomalous exponents.
Four-Handed Dentistry Revisited

A great deal of new technology has been integrated into the modern dental office during the last several decades. However, no product can increase productivity and reduce stress and strain on the dental team as much as using the singular concept of four-handed dentistry. The research of the 1950s is undaunted in its impact on productivity. Combined with the practice of ergonomics in the workplace, this concept must be revisited by the dental profession. The young dentists of the 21st Century have had minimal exposure to true four-handed dentistry. This article, the first in a series, re-introduces the basic principles of a research-oriented concept.
Principles of food flavor analysis

Abstract: This chapter presents a discussion of the most commonly used methods for the analysis of aroma, taste and chemesthetic compounds found in foods. Each group of flavor compounds presents unique challenges and thus has a different focus. The methodology for aroma analysis (i.e. primarily isolation of an aroma fraction) has been well researched and, thus, these methods are discussed in some detail. The analysis of taste compounds has been studied much less and having no standard methods, is discussed using examples from the literature. Since chemesthetic compounds may be either volatile or non-volatile, this discussion is again done by example. In all cases, the discussion focuses on getting an appropriate food flavor isolate to the proper instrument (primarily gas chromatography/mass spectrometry (GC-MS) or high-performance liquid chromatography/mass spectrometry (HPLC-MS)) with no discussion of the instrumental methods used: these instruments are described in detail in many texts.
Controlled synthesis of colloidal silver nanoparticles in organic solutions: empirical rules for nucleation engineering

Controlled synthesis of colloidal nanoparticles in organic solutions is among the most intensely studied topics in nanoscience because of the intrinsic advantages in terms of high yield and high uniformity in comparison with aqueous synthesis. However, systematic studies on the formation mechanism of nanoparticles with precisely tailored physical parameters are barely reported. In this tutorial review, we take the synthesis of different Ag nanoparticles as an example to rule out the general principles for controlling the nucleation process involved in the formation of colloidal Ag nanoparticles in organic solutions, which enables the synthesis of high-quality nanoparticles.
SHAREHOLDER TRADING PRACTICES AND CORPORATE INVESTMENT HORIZONS

We investigate how shareholder trading practices might be linked to corporate investment horizons. We examine two possible linkages and analyze a range of data relevant to them. The first is excess volatility, which occurs when stock prices react not only to news about economic fundamentals, but also to trades based on non-fundamental factors. Excess volatility could lead to a higher cost of capital, and thereby reduce long-term corporate investment. The second linkage derives from an information ea between management and outside shareholders. In the presence of such a gap, maximizing short-run and long-run stock prices are not the same thing. Management may be able to raise current stock prices by undertaking certain actions that will reduce long-run value. In such a case, management faces the dilemma of which shareholders to please: those who do not plan to hold the stock for the long-run versus those who do. As shareholder horizons shorten, it can become more difficult to focus exclusively on maximizing long-run value. With respect to excess volatility, our basic conclusions are that neither changes in trading practices over time nor differences in trading practices across countries contribute significantly to any underinvestment problem. There is no evidence to indicate that measures to reduce trading volume (such as transactions taxes) would lower stock-price volatility in a way that would stimulate investment. With respect to the information gap hypothesis, we find "circumstantial' evidence consistent with certain preconditions for underinvestment. This is not, however, evidence of underinvestment itself. In addition, many of the forces that can lead to underinvestment -- such as hostile takeovers -- are also related to other, positive aspects of economic performance. Policy responses therefore involve a difficult set of tradeoffs. (This abstract was borrowed from another version of this item.)
Classification-aware hidden-web text database selection

Many valuable text databases on the web have noncrawlable contents that are “hidden” behind search interfaces. Metasearchers are helpful tools for searching over multiple such “hidden-web” text databases at once through a unified query interface. An important step in the metasearching process is database selection, or determining which databases are the most relevant for a given user query. The state-of-the-art database selection techniques rely on statistical summaries of the database contents, generally including the database vocabulary and associated word frequencies. Unfortunately, hidden-web text databases typically do not export such summaries, so previous research has developed algorithms for constructing approximate content summaries from document samples extracted from the databases via querying. We present a novel “focused-probing” sampling algorithm that detects the topics covered in a database and adaptively extracts documents that are representative of the topic coverage of the database. Our algorithm is the first to construct content summaries that include the frequencies of the words in the database. Unfortunately, Zipf's law practically guarantees that for any relatively large database, content summaries built from moderately sized document samples will fail to cover many low-frequency words; in turn, incomplete content summaries might negatively affect the database selection process, especially for short queries with infrequent words. To enhance the sparse document samples and improve the database selection decisions, we exploit the fact that topically similar databases tend to have similar vocabularies, so samples extracted from databases with a similar topical focus can complement each other. We have developed two database selection algorithms that exploit this observation. The first algorithm proceeds hierarchically and selects the best categories for a query, and then sends the query to the appropriate databases in the chosen categories. The second algorithm uses “shrinkage,” a statistical technique for improving parameter estimation in the face of sparse data, to enhance the database content summaries with category-specific words. We describe how to modify existing database selection algorithms to adaptively decide (at runtime) whether shrinkage is beneficial for a query. A thorough evaluation over a variety of databases, including 315 real web databases as well as TREC data, suggests that the proposed sampling methods generate high-quality content summaries and that the database selection algorithms produce significantly more relevant database selection decisions and overall search results than existing algorithms.
Older Adults' Contributions to the Tsimane Forager-Farmer Economy

This photo-essay shows and discusses snapshots of Tsimane older adults' contributions to the Tsimane Forager-Farmer Economy - especially via complimentary services such as caretaking, teaching, and chores.
Solvent-free ketone hydrogenations catalyzed by molybdenum complexes

Et2CO is hydrogenated under solvent-free conditions using a catalyst prepared by hydride abstraction from HMo(CO)2[η5:η1-C5H4(CH2)2PCy2]; the catalyst functions at low catalyst loadings (<0.4 mol%).
Concentration of the spectral measure of large Wishart matrices with dependent entries

We derive concentration inequalities for the spectral measure of large random matrices, allowing for certain forms of dependence. Our main focus is on empirical covariance (Wishart) matrices, but general symmetric random matrices are also considered.
Spectrum Sharing with Distributed Relay Selection and Clustering

We consider a spectrum-sharing network where n secondary relays are used to increase secondary rate and also mitigate interference on the primary by reducing the required overall secondary emitted power. We propose a distributed relay selection and clustering framework, obtain closed-form expressions for the secondary rate, and show that secondary rate increases proportionally to log n. Remarkably, this is on the same order as the growth rate obtained in the absence of a primary system and its imposed constraints. Our results show that to maximize the rate, the secondary relays must transmit with power proportional to n-1 (thus the sum of relay powers is bounded) and also that the secondary source may not operate at its maximum allowable power. The tradeoff between the secondary rate and the interference on the primary is also characterized, showing that the primary interference can be reduced asymptotically to zero as n increases, while still maintaining a secondary rate that grows proportionally to log n. Finally, to address the rate loss due to half-duplex relaying in the secondary, we propose an alternating relay protocol and investigate its performance.
Microstructural Developments and Dielectric Properties of Rapid Thermally Processed PZT Thin Films Derived by Metallo‐organic Decomposition

Microstructural developments and dielectric properties of lead zirconate titanate thin films (0.22 4mUm) with the composition Pb(Zr0.53Ti0.47)O3 were studied. The films were prepared by metallo-organic decomposition (MOD) and rapid thermal processing (RTP) in the temperature range 475–825°C for 2 min in an oxygen gas flow with and without post-annealing. An amorphous–pyrochlore–perovskite phase transformation is indicated at or below 525°C RTF temperatures while a direct amorphous-to-perovskite phase transformation is indicated at higher RTP temperatures. A decrease in grain size with increasing temperature is correlated with an increase in and dominance of nucleation of perovskite sites. The best dielectric and fatigue properties were exhibited by films processed in the temperature range 725–775°C. Hysteresis loops tended toward squareness and polarization charges increased with increased temperature. Furthermore, 45% of the initial charge remained after 109switching reversals. A degradation, however, was observed in both properties at higher temperatures.
The cost of uncertain life span

Much uncertainty surrounds the length of human life. The standard deviation in adult life span is about 15 years in the USA, and theory and evidence suggest that it is costly. I calibrate a utility-theoretic model that shows that 1 year in standard deviation is worth about half a life year. Differences in variance exacerbate health inequalities between and among rich and poor countries. Accounting for the cost of life-span variance appears to amplify recently discovered patterns of convergence in world average human well-being because the component of variance due to infant mortality has exhibited even more convergence than life expectancy.
Neighborhood Effects on Crime for Female and Male Youth: Evidence from a Randomized Housing Voucher Experiment

The Moving to Opportunity (MTO) demonstration assigned housing vouchers via random lottery to public housing residents in five cities. We use the exogenous variation in residential locations generated by MTO to estimate neighborhood effects on youth crime and delinquency. The offer to relocate to lower-poverty areas reduces arrests among female youth for violent and property crimes, relative to a control group. For males the offer to relocate reduces arrests for violent crime, at least in the short run, but increases problem behaviors and property crime arrests. The gender difference in treatment effects seems to reflect differences in how male and female youths from disadvantaged backgrounds adapt and respond to similar new neighborhood environments.
Sweet success: ionic liquids derived from non-nutritive sweeteners

The anions of the sweeteners saccharin and acesulfame form ionic liquids when paired with a variety of organic cations.
The Chess conjecture

We prove that the homotopy class of a Morin mapping f : P p ! Q q with p q odd contains a cusp mapping. This armatively solves a strengthened version of the Chess conjecture (5),(3). Also, in view of the Saeki-Sakuma theorem (10) on the Hopf invariant one problem and Morin mappings, this implies that a manifold P p with odd Euler characteristic does not admit Morin mappings into R 2k+1 for p 2k +1 6 ; 3 ;7. AMS Classication 57R45; 58A20, 58K30
Constructing ordered orthogonal arrays via sudoku

For prime powers q we use “strongly orthogonal” linear sudoku solutions of order q2 to construct ordered orthogonal arrays of type OOA(4,s, 2,q), and for each q we present a range of values of s for which these constructions are valid. These results rely strongly on flags of subspaces in a four-dimensional vector space over a finite field.
Hypersonic Flow over a Blunt Body with Plasma Injection

The drag reduction of blunt body in hypersonic flow via plasma injection has been investigated by a combined experimental and computational effort. The counterflow plasma jet generated by a plasma torch has a vibrionic temperature of 4400 K, an electronic temperature around 20,000 K, and electron density greater than 3 × 1012/cm3. At a fixed injection stagnation pressure and in the absence of an applied magnetic field, the plasma injection actually increases drag above that of room-temperature air due to a decreased mass flow rate at the elevated temperature. However, at an identical mass flow rate, the plasma injection reveals a greater drag reduction than the room-temperature air counterpart through thermal energy deposition. From experimental measurements, an overwhelming major portion of the drag reduction is derived from the viscous-inviscid interaction of the counterflow jet and thermal energy deposition. The numerical results of Navier-Stokes equations with a local equilibrium plasma composition also confirm this observation.
Medical Education In The United States, 1960–1987

The four DataWatches in this issue of Health Affairs provide data on several aspects of medical education. First, Paul Jolly of the Association of American Medical Colleges (AAMC) gives an in-depth...
Let’s Talk About the Money: Spousal Communication, Expenditures, and Farm Production

A burgeoning body of literature highlights asymmetric information among household members. However, little is known about the source of the asymmetry and its effect on efficiency. Using a unique survey of Ghanaian households, we examine the accuracy of spousal cross reports and the effect of discrepancies on farm production. We find that information problems pertain to scale (the quantity of resources) and scope (the distribution of resources), as well as allocation decisions on the margin (Engel curves). Moreover, we find that information asymmetries lead to inefficiency in production, and the effect is equivalent to about 15% of the variation across households.
A method for the facile synthesis of ring-A hydroxylated flavones

Abstract A general method for the facile synthesis of ring-A hydroxylated flavones is described. Treatment of the hydroxylated acetophenones 6a–d with enough lithium bis(trimethyl)silyl amide to deprotonate all of the phenols as well as to generate the lithium enolate of the ketone, followed by addition of the acid chlorides 7a–d, gave the 1,3-diketones 8a–g, which were cyclized to the desired products 9a–g in high yield.
Tracking-based semi-supervised learning

We consider a semi-supervised approach to the problem of track classification in dense three-dimensional range data. This problem involves the classification of objects that have been segmented and tracked without the use of a class-specific tracker. This paper is an extended version of our previous work. We propose a method based on the expectation-maximization algorithm: iteratively (1) train a classifier, and (2) extract useful training examples from unlabeled data by exploiting tracking information. We evaluate our method on a large multiclass problem in dense range data collected from natural street scenes. When given only three hand-labeled training tracks of each object class, the final accuracy of the semi-supervised algorithm is comparable to that of the fully supervised equivalent which uses two orders of magnitude more. Further, we show experimentally that the accuracy of a classifier considered as a function of human labeling effort can be substantially improved using this method. Finally, we show that a simple algorithmic speedup based on incrementally updating a boosting classifier can reduce learning time by a factor of three.
Two injective proofs of a conjecture of Simion

Simion (J. Combin. Theory Ser. A 94 (1994) 270) conjectured the unimodality of a sequence counting lattice paths in a grid with a Ferrers diagram removed from the northwest corner. Recently, Hildebrand (J. Combin. Theory Ser. A 97 (2002) 108) and then Wang (A simple proof of a conjecture of Simion, J. Combin. Theory Ser. A 100 (2002) 399) proved the stronger result that this sequence is actually log concave. Both proofs were mainly algebraic in nature. We give two combinatorial proofs of this theorem.
Detached-Eddy Simulation of Transonic Limit Cycle Oscillations Using High Order Schemes

This paper is to investigate the ∞ow non-linearity of the ∞uid-structural interaction using detached eddy simulation (DES) of turbulence. A low difiusion E-CUSP (LDE) scheme with 5th order WENO scheme is employed to calculate the inviscid ∞uxes. A fully conservative 4th order central difierencing is used for the viscous terms. A fully coupled ∞uid-structural model is employed. The limited cycle oscillation (LCO) of the NLR7301 airfoil is simulated in 2D using RANS method and in 3D using DES method. For the cases computed in this paper, the predicted LCO frequency, amplitudes, averaged lift and moment, all agree excellently with the experiment. The solutions appear to have bifurcation and are dependent on the initial flelds or initial perturbation. The developed computational ∞uid dynamics (CFD)/computational structure dynamics (CSD) simulation is able to capture the LCO with very small amplitudes measured in the experiment. This is attributed to the high order low difiusion schemes, fully coupled FSI model, and the turbulence model used. This research appears to be the flrst time that a numerical simulation of LCO matches the experiment. The simulation conflrms several observations of the experiment.
Quantification of Fastener- Hole Quality

This paper describes a method, the Equivalent Initial Quality Method, of quantifying the quality of fastener holes. This quantification is accomplished by representing the imperfections that are either inherent in a material or introduced during the manufacturing of a structural component with a fatigue crack of a particular size and shape. This initial quality representation can be used in a crack-propagation analysis to determine the life of the structural component. For example, the Equivalent Initial Quality Method can be used in design by providing the assumptions necessary to satisfy the USAF airplane damage tolerance design requirements (MIL-A-83444) and the USAF airplane durability design requirements (MIL-A-8866B). The method was used to assess the manufacturing quality of the F-4C/D/E(S) and A-7D aircraft. The more recent A-7D quality assessment is discussed in detail and the equivalent initial quality results for the F-4C/D and A-7D aircraft are presented. The potential applications (e.g., determination of required inspection intervals and maintenance and modification schedules, use in design, assessment of quality of manufacturing procedures, etc.), as well as the possible limitations (e.g., sensitivity of method to stress level, material, etc.), of the Equivalent Initial Quality Method are discussed.
Getting Right with Nature Anthropocentrism, Ecocentrism, and Theocentrism

The past century has witnessed unprecedented economic growth and prosperity along with unprecedented depredations upon nature. To resolve these developments, there is debate between two moral postures. One takes a human-centered, or anthropocentric, view of our relationship to nature to emphasize the value of securing the resources needed for further development. The other takes an environment-centered, or ecocentric, view of our relationship to nature to emphasize the value of conserving her integrity and beauty. This article explores tensions underling these two views and finds that neither adequately reconciles us to nature. This article offers an alternative, theocentric view of our relationship to nature, founded upon Catholic Christianity, that reconciles in God our value for resources and nature and establishes a divine order of man and nature apart from human egoism and intentions. This article concludes with a discussion of the implications of this theocentric view for environmental policy and pr...
Wiki surveys: open and quantifiable social data collection

In the social sciences, there is a longstanding tension between data collection methods that facilitate quantification and those that are open to unanticipated information. Advances in technology now enable new, hybrid methods that combine some of the benefits of both approaches. Drawing inspiration from online information aggregation systems like Wikipedia and from traditional survey research, we propose a new class of research instruments called wiki surveys. Just as Wikipedia evolves over time based on contributions from participants, we envision an evolving survey driven by contributions from respondents. We develop three general principles that underlie wiki surveys: they should be greedy, collaborative, and adaptive. Building on these principles, we develop methods for data collection and data analysis for one type of wiki survey, a pairwise wiki survey. Using two proof-of-concept case studies involving our free and open-source website www.allourideas.org, we show that pairwise wiki surveys can yield insights that would be difficult to obtain with other methods.
A REFINED WARING PROBLEM FOR FINITE SIMPLE GROUPS

Let $w_{1}$ and $w_{2}$ be nontrivial words in free groups $F_{n_{1}}$ and $F_{n_{2}}$ , respectively. We prove that, for all sufficiently large finite nonabelian simple groups $G$ , there exist subsets $C_{1}\subseteq w_{1}(G)$ and $C_{2}\subseteq w_{2}(G)$ such that $|C_{i}|=O(|G|^{1/2}\log ^{1/2}|G|)$ and $C_{1}C_{2}=G$ . In particular, if $w$ is any nontrivial word and $G$ is a sufficiently large finite nonabelian simple group, then $w(G)$ contains a thin base of order $2$ . This is a nonabelian analog of a result of Van Vu [‘On a refinement of Waring’s problem’, Duke Math. J. 105(1) (2000), 107–134.] for the classical Waring problem. Further results concerning thin bases of $G$ of order $2$ are established for any finite group and for any compact Lie group $G$ .
Laboratory Experiments in Political Economy

This article summarizes a small part of the literature on laboratory experiments in political economy. The experiments discussed are primarily aimed at testing predictions of equilibrium models of voting in committees and elections. The specific topics discussed are voter turnout, the Condorcet jury theorem, and the swing voter's curse. The latter two topics address questions of information aggregation by voting rules. All the experiments find significant evidence of strategic voting and, with a few exceptions, find support for the equilibrium predictions of the theories.
The fibonacci numbers-exposed

Among numerical sequences, the Fibonacci numbers Fn have achieved a kind of celebrity status. Indeed, Koshy gushingly refers to them as one of the "two shining stars in the vast array of integer sequences" [16, p. xi]. The second of Koshy's "shining stars" is the Lucas numbers, a close relative of the Fibonacci numbers, about which we will say more below. The Fibonacci numbers are famous for possessing wonderful and amazing properties. Some are well known. For example, the sums and differences of Fibonacci numbers are Fibonacci numbers, and the ratios of Fibonacci numbers converge to the golden mean. Others are less familiar. Did you know that any four consecutive Fibonacci numbers can be combined to form a Pythagorean triple? Or how about this: The greatest common divisor of two Fibonacci numbers is another Fibonacci number. More precisely, the gcd of F, and Fm is Fk, where k is the gcd of n and m.
Development of Bifunctional Salen Catalysts: Rapid, Chemoselective Alkylations of α-Ketoesters

Lewis acid−Lewis base salen complexes have been identified as highly efficient catalysts for the addition of dialkylzincs to α-ketoesters. In contrast to aldehydes or ketones, the reaction between diethylzinc and α-ketoesters is significant in the absence of catalyst. In the presence of catalyst, the reaction rate is increased over 100-fold relative to the background. Furthermore, the reduction product, which is a major coproduct with other catalysts, is not observed with these bifunctional salens. As a result, high yields of the addition products can be obtained (57−99%). Both the Lewis acid and Lewis base portions of the catalyst are critical to the reactivity and selectivity. The two separate portions of the catalyst have been shown to function in a cooperative manner.
On the cost of participating in a peer-to-peer network

In this paper, we model the cost incurred by each peer participating in a peer-to-peer network. Such a cost model allows to gauge potential disincentives for peers to collaborate, and provides a measure of the “total cost” of a network, which is a possible benchmark to distinguish between proposals. We characterize the cost imposed on a node as a function of the experienced load and the node connectivity, and express benefits in terms of cost reduction. We discuss the notion of social optimum with respect to the proposed cost model, and show how our model applies to a few proposed routing geometries for distributed hash tables (DHTs). We further outline a number of open questions this research has raised.
Magnetism in Fe-based superconductors.

In this review, we present a summary of experimental studies of magnetism in Fe-based superconductors. The doping dependent phase diagram shows strong similarities to the generic phase diagram of the cuprates. Parent compounds exhibit magnetic order together with a structural phase transition, both of which are progressively suppressed with doping, allowing superconductivity to emerge. The stripe-like spin arrangement of Fe moments in the magnetically ordered state shows identical in-plane structure for the RFeAsO (R = rare earth) and AFe2As2 (A = Sr, Ca, Ba, Eu and K) parent compounds, notably different than the spin configuration of the cuprates. Interestingly, Fe1 + yTe orders with a different spin order despite having very similar Fermi surface topology. Studies of the spin dynamics of the parent compounds show that the interactions are best characterized as anisotropic three-dimensional interactions. Despite the room temperature tetragonal structure, analysis of the low temperature spin waves under the assumption of a Heisenberg Hamiltonian indicates strong in-plane anisotropy with a significant next-nearest-neighbor interaction. For the superconducting state, a resonance, localized in both wavevector and energy, is observed in the spin excitation spectrum as for the cuprates. This resonance is observed at a wavevector compatible with a Fermi surface nesting instability independent of the magnetic ordering of the relevant parent compound. The resonance energy (Er) scales with the superconducting transition temperature (TC) as Er ~ 4.9kBTC, which is consistent with the canonical value of ~ 5kBTC observed for the cuprates. Moreover, the relationship between the resonance energy and the superconducting gap, Δ, is similar to that observed for many unconventional superconductors (Er/2Δ ~ 0.64).
Many Body Physics: Unfinished Revolution

The study of many body physics has provided a scientific playground of surprise and continuing revolution over the past half century. The serendipitous discovery of new states and properties of matter, phenomena such as superfluidity, the Meissner, the Kondo and the fractional quantum hall effect, have driven the development of new conceptual frameworks for our understanding about collective behavior, the ramifications of which have spread far beyond the confines of terrestrial condensed matter physics – to cosmology, nuclear and particle physics. Here I shall selectively review some of the developments in this field, from the cold-war period, until the present day. I describe how, with the discovery of new classes of collective order, the unfolding puzzles of high temperature superconductivity and quantum criticality, the prospects for major conceptual discoveries remain as bright today as they were more than half a century ago.
Secure Context-Sensitive Authorization

There is a recent trend toward rule-based authorization systems to achieve flexible security policies. Also, new sensing technologies in pervasive computing make it possible to define context-sensitive rules, such as "allow database access only to staff who are currently located in the main office." However, these rules, or the facts that are needed to verify authority, often involve sensitive context information. This paper presents a secure context-sensitive authorization system that protects confidential information in facts or rules. Furthermore, our system allows multiple hosts in a distributed environment to perform the evaluation of an authorization query in a collaborative way; we do not need a universally trusted central host that maintains all the context information. The core of our approach is to decompose a proof for making an authorization decision into a set of subproofs produced on multiple different hosts, while preserving the integrity and confidentiality policies of the mutually untrusted principals operating these hosts
A MODEL OF ACTIVITY PARTICIPATION AND TRAVEL INTERACTIONS BETWEEN HOUSEHOLD HEADS

A structural model is used to explain activity interactions between heads of households and, in so doing, to explain household demand for travel. The model attempts to capture links between activity participation and associated derived travel, links between activities performed by male and female heads, links between types of travel, and time-budget feedbacks from travel to activity participation. Data for pairs of opposite gender heads of households are from the 1994 Portland Activity and Travel Survey. The results suggest that a feedback mechanism should be introduced in trip generation models to reflect the effect of activity frequency and duration on the level of associated travel.
Manipulating biological agents and cells in micro-scale volumes for applications in medicine

Recent technological advances provide new tools to manipulate cells and biological agents in micro/nano-liter volumes. With precise control over small volumes, the cell microenvironment and other biological agents can be bioengineered; interactions between cells and external stimuli can be monitored; and the fundamental mechanisms such as cancer metastasis and stem cell differentiation can be elucidated. Technological advances based on the principles of electrical, magnetic, chemical, optical, acoustic, and mechanical forces lead to novel applications in point-of-care diagnostics, regenerative medicine, in vitro drug testing, cryopreservation, and cell isolation/purification. In this review, we first focus on the underlying mechanisms of emerging examples for cell manipulation in small volumes targeting applications such as tissue engineering. Then, we illustrate how these mechanisms impact the aforementioned biomedical applications, discuss the associated challenges, and provide perspectives for further development.
Supply-chain redesign to reduce safety stock levels: sequencing and merging operations

We investigate the impact of the process of manufacturing and distribution on the safety stock levels in a supply chain. A pipeline hedging method is used to derive a model for estimating the safety stock levels. We propose methods and guidelines to redesign the manufacturing and distribution process to minimize the total safety stock investment for a specified service level. The product family consisting of one product and two products is studied in detail. Conditions and insights for better supply-chain management are developed. These enable us not only to decide when a process redesigning activity is appropriate, but also to suggest the scale and the format of the process redesign. Based on the results obtained, two procedures-resequencing and merging-are developed. Finally, we demonstrate how these procedures can be extended to product families consisting of multiple products in a hierarchical manner.
Synthesis of α-amino acid derivatives and amines via activation of simple alkyl halides by zinc in water

A method for the synthesis of α-amino acid derivatives and amines is developed via a zinc-mediated conjugate addition reaction of alkyl halides to α-phthalimidoacrylate derivatives and nucleophilic addition to imines in the presence of NH4Cl in water. No reaction was observed in the absence of water.
Palladium-catalyzed synthesis of quinolines from allylic alcohols and o-iodoaniline

Abstract The palladium-catalyzed coupling of allylic alcohols and o -iodoaniline provides a convenient, one-step synthesis of quinolines.
On the scalability of cooperative time synchronization in pulse-connected networks

The problem of time synchronization in dense wireless networks is considered. Well-established synchronization techniques suffer from an inherent scalability problem in that synchronization errors grow with an increasing number of hops across the network. In this work, a model for communication in wireless networks is first developed, and then the model is used to define a new time synchronization mechanism. A salient feature of the proposed method is that, in the regime of asymptotically dense networks, it can average out all random errors and maintain global synchronization in the sense that all nodes in the multihop network can see identical timing signals. This is irrespective of the distance separating any two nodes.
Near-optimum regulators for stochastic linear singularly perturbed systems

This paper presents a new approach to the decomposition and approximation of linear-quadratic-Gaussian estimation and control problems for singularly perturbed systems. The Kalman filter is decomposed into separate slow-mode and fast-mode filters via the use of a decoupling transformation. A near-optimal control law is derived by approximating the coefficients of the optimal control law. The order of approximation of the optimal performance is 0(\mu^{N}) where N is the order of approximation of the coefficients.
Reversed Hardy–Littewood–Sobolev Inequality

In this paper, we obtain a reversed Hardy-Littlewood-Sobolev in- equality: for 0 0, such that
Efficiency-revenue trade-offs in auctions

When agents with independent priors bid for a single item, Myerson's optimal auction maximizes expected revenue, whereas Vickrey's second-price auction optimizes social welfare. We address the natural question of trade-offs between the two criteria, that is, auctions that optimize, say, revenue under the constraint that the welfare is above a given level. If one allows for randomized mechanisms, it is easy to see that there are polynomial-time mechanisms that achieve any point in the trade-off (the Pareto curve) between revenue and welfare. We investigate whether one can achieve the same guarantees using deterministic mechanisms. We provide a negative answer to this question by showing that this is a (weakly) NP-hard problem. On the positive side, we provide polynomial-time deterministic mechanisms that approximate with arbitrary precision any point of the trade-off between these two fundamental objectives for the case of two bidders, even when the valuations are correlated arbitrarily. The major problem left open by our work is whether there is such an algorithm for three or more bidders with independent valuation distributions.
High Resolution Optical/Near-Infrared Imaging of Cool Ultraluminous Infrared Galaxies

We present here new multiwavelength observations with 1.5 and 4x the spatial resolution of previous ground-based observations at optical and near-infrared wavelengths; despite being ground-based, they allow us to isolate interesting features such as the star-forming knots detected in the warm ULIG sample.
Perceiving the properties of objects using arm movements: workspace-dependent effects

A paradigm is described in which subjects feel virtual objects, created using a two-link robot arm under computer control. Preliminary results show there are systematic distortions in how relative length and relative compliance (preliminary results) are perceived by the subjects, who use only their arm movements in making psychophysical judgments. These distortions depend on the location of the objects in the workspace, and they appear to be related to the dynamical properties of the arm itself. >
Remarks on the Stability of Viscometric Flow.

We study the stability of viscometric flow using the type of short memory introduced by Akbay, Becker, Krozer and Sponagel. The instability found by these researchers is recognized as a “change of type” leading to non-evolutionary character of the governing equations. We also address the question of justification for the short memory assumption and find that it cannot be justified for some of the more popular rheological models.
Hidden Survivorship in Hedge Fund Returns

This study identifies a previously unreported bias in the TASS database. Owing to a merger with the Tremont database, 60 percent of the funds added to the TASS database between April 1999 and November 2001 are likely to be survivors (i.e., funds that were selected only from funds that were live as of 31 March 1999). The resulting survivorship bias is substantial, averaging more than 5 percent a year. What would normally be termed the backfill period actually represents hidden survivorship. A sorting algorithm to exclude these fund histories is proposed.
Perturbative search for dead-end CFTs

To explore the possibility of self-organized criticality, we look for CFTs without any relevant scalar deformations (a.k.a. dead-end CFTs) within power-counting renormalizable quantum field theories with a weakly coupled Lagrangian description. In three dimensions, the only candidates are pure (Abelian) gauge theories, which may be further deformed by Chern-Simons terms. In four dimensions, we show that there are infinitely many non-trivial candidates based on chiral gauge theories. Using the three-loop beta functions, we compute the gap of scaling dimensions above the marginal value, and it can be as small as O(10^(-5)) and robust against the perturbative corrections. These classes of candidates are very weakly coupled and our perturbative conclusion seems difficult to refute. Thus, the hypothesis that non-trivial dead-end CFTs do not exist is likely to be false in four dimensions.
Electronic Structure and Derived Linear and Nonlinear Optical Properties of Chalcopyrites

The electronic band structures were calculated for a number of chalcopyrites in both the II-IV-V 2 and I-III-VI 2 families using the linear muffin-tin orbital method. From these band structures, the second harmonic generation coefficients were calculated using a recently developed methodology in which a separation is made of inter- and intraband contributions. We found that the high value of d 36 in CdGeAs 2 is in large part due to the fact, that in this material, unlike in the other chalcopyrites, almost no compensation occurs between inter- and intraband contributions, the former one being unusually small. For the case of ZnGeP 2 , a detailed investigation of the band structure, reveals that it has an indirect band gap rather than a pseudodirect one. The implications of this for the interpretation of the optical spectra are discussed. Finally, for the I-III-VI 2 materials, we find that the Te based materials have far higher d 36 than the selenides. Combined with their potential for non-critical phase matching, this makes AgGaTe 2 an interesting compound.
An optimal algorithm for intersecting three-dimensional convex polyhedra

This paper describes a linear-time algorithm for computing the intersection of two convex polyhedra in 3-space. Applications of this result to computing intersections, convex hulls, and Voronoi diagrams are also given.
Adaptive voltage control with distributed energy resources: Algorithm, theoretical analysis, simulation, and field test verification

Distributed energy resources (DE) or distributed generators (DG) with power electronics interfaces and logic control using local measurements are capable of providing reactive power related ancillary system services. In particular, local voltage regulation has drawn much attention in regards to power system reliability and voltage stability, especially from past major cascading outages. This paper addresses the challenges of controlling DEs to regulate local voltage in distribution systems. An adaptive voltage control method has been proposed to dynamically modify control parameters to respond to system changes. Theoretical analysis shows that there exists a corresponding formulation of the dynamic control parameters; hence the adaptive control method is theoretically solid. Both simulation and field experiment test results at the Distributed Energy Communications and Controls (DECC) Laboratory confirm that this method is capable of satisfying the fast response requirement for operational use without causing oscillation, inefficiency, or system equipment interference. Since this method has a high tolerance to real-time data shortage and is widely adaptive to variable power system operational situations, it is quite suitable for broad utility application.
Line-by-line pulse shaping control for optical arbitrary waveform generation

We demonstrate line-by-line pulse shaping control for optical arbitrary waveform generation (O-AWG). Independent manipulation of individual spectral lines from a mode-locked frequency comb leads to synthesis of user-specified ultrafast optical waveforms with unprecedented frequency resolution.
Joint assembly and genetic mapping of the Atlantic horseshoe crab genome reveals ancient whole genome duplication

Horseshoe crabs are marine arthropods with a fossil record extending back approximately 450 million years. They exhibit remarkable morphological stability over their long evolutionary history, retaining a number of ancestral arthropod traits, and are often cited as examples of “living fossils.” As arthropods, they belong to the Ecdysozoa, an ancient super-phylum whose sequenced genomes (including insects and nematodes) have thus far shown more divergence from the ancestral pattern of eumetazoan genome organization than cnidarians, deuterostomes and lophotrochozoans. However, much of ecdysozoan diversity remains unrepresented in comparative genomic analyses. Here we apply a new strategy of combined de novo assembly and genetic mapping to examine the chromosome-scale genome organization of the Atlantic horseshoe crab, Limulus polyphemus. We constructed a genetic linkage map of this 2.7 Gbp genome by sequencing the nuclear DNA of 34 wild-collected, full-sibling embryos and their parents at a mean redundancy of 1.1x per sample. The map includes 84,307 sequence markers grouped into 1,876 distinct genetic intervals and 5,775 candidate conserved protein coding genes. Comparison with other metazoan genomes shows that the L. polyphemus genome preserves ancestral bilaterian linkage groups, and that a common ancestor of modern horseshoe crabs underwent one or more ancient whole genome duplications 300 million years ago, followed by extensive chromosome fusion. These results provide a counter-example to the often noted correlation between whole genome duplication and evolutionary radiations. The new, low-cost genetic mapping method for obtaining a chromosome-scale view of non-model organism genomes that we demonstrate here does not require laboratory culture, and is potentially applicable to a broad range of other species.
The Structure of Constant Elasticity Demand Models

The demand model with constant price and income elasticities has been used extensively in applied agricultural economics. This paper analyzes the structure of incomplete systems of constant elasticity demand functions. It is demonstrated that there is a duality theory for incomplete demand systems that is analogous to the duality theory for complete systems. This theory permits the recovery of that portion of the direct and indirect preferences pertaining to the goods of interest, and we can calculate exact welfare measures for changes in income and in the prices of these goods. For an incomplete system of constant elasticity demands, the Slutsky symmetry restrictions for integrability are presented and the implied structure of the direct and indirect preferences with respect to the prices and goods of interest is derived.