cssi/SciSciGPT-SciSciNet huggingface dataset:
Trends in instrument systems for deep space exploration

Instrument systems for deep space exploration have undergone dramatic changes in the last few years. They are smaller, lighter and less power hungry. The line between science instruments and spacecraft sensors is blurring. New vehicles, missions, goals, environments and types of instruments are changing the design of instrument suites. Finally, integrated instrument suites are becoming more common. Using Cassini spacecraft instruments as a benchmark, instrument suites on the DS-1 and DS-2 spacecraft are discussed along with designs for MECA, MER and the Subsurface Explorer, in the context of these trends.
Evolution of Ohmically Heated Hot Jupiters

We present calculations of thermal evolution of hot Jupiters with various masses and effective temperatures under ohmic dissipation. The resulting evolutionary sequences show a clear tendency toward inflated radii for effective temperatures that give rise to significant ionization of alkali metals in the atmosphere, compatible with the trend of the data. The degree of inflation shows that ohmic dissipation along with the likely variability in heavy element content can account for all of the currently detected radius anomalies. Furthermore, we find that in the absence of a massive core, low-mass hot Jupiters can overflow their Roche lobes and evaporate on Gyr timescales, possibly leaving behind small rocky cores.
Catching Packet Droppers and Modifiers in Wireless Sensor Networks

Packet dropping and modification are common attacks that can be launched by an adversary to disrupt communication in wireless multihop sensor networks. Many schemes have been proposed to mitigate or tolerate such attacks, but very few can effectively and efficiently identify the intruders. To address this problem, we propose a simple yet effective scheme, which can identify misbehaving forwarders that drop or modify packets. Extensive analysis and simulations have been conducted to verify the effectiveness and efficiency of the scheme.
Directions in tropical agroforestry research: past, present, and future

Reflections on the past two decades of organized research in tropical agroforestry raise several issues. Research efforts started with an inductive and experiential approach but have subsequently followed a deductive and experimental approach that includes hypothesis testing and the development of predictive capability; agroforestry research is thus being transformed into a rigorous scientific activity. The research agenda, so far, has given high priority to soil fertility and other biophysical interactions, less priority to anthropological and sociological aspects, and little priority to evaluating costs and returns, pests and diseases, and the so-called non-timber forest (tree) products. Moreover, larger-spatial-scale issues, such as carbon sequestration, water quality, and biodiversity conservation, have been neglected because of the emphasis on field- and farm-scale studies.
The Economic Consequences of Parental Leave Mandates: Lessons from Europe

This study investigates the economic consequences of rights to paid parental leave in nine European countries over the 1969 through 1993 period. Since women use virtually all parental leave in most nations, men constitute a reasonable comparison group, and most of the analysis examines how changes in paid leave affect the gap between female and male labor market outcomes. The employment-to-populations ratios of women in their prime childbearing years are also compared with those of corresponding aged men and older females. Parental leave is associated with increases in women's employment, but with reductions in their relative wages at extended durations.
Rhodium-Catalyzed Asymmetric Hydroformylation of N-Allylamides: Highly Enantioselective Approach to β2-Amino Aldehydes

The present new asymmetric hydroformylation is applicable to a wide range of allylic compounds providing an alternative route to 2-amino aldehydes, acids, and alcohols with excellent enantioselectivity.
Prizes and patents: Using market signals to provide incentives for innovations

We consider environments in which agents other than innovator receive the signals about the quality of innovation. We study whether mechanisms can be found which exploit market information to provide appropriate incentives for innovation. If such mechanisms are used, the innovator has incentives to manipulate market signals. We show that if an innovator cannot manipulate market signals, then the efficient levels of innovation can be uniquely implemented without deadweight losses – for example, by using prizes. Patents are necessary if the innovator can manipulate market signals. For an intermediate case of costly signal manipulation, both patents and prizes may be optimal.
HOLOMORPHIC BUNDLES AND MANY-BODY SYSTEMS

We show that spin generalization of elliptic Calogero-Moser system, elliptic extension of Gaudin model and their cousins are the degenerations of Hitchin systems. Applications to the constructions of integrals of motion, angle-action variables and quantum systems are discussed. The constructions of classical systems are motivated by Conformal Field Theory, and their quantum counterparts can be thought of as being the degenerations of the critical level Knizhnik-Zamolodchikov-Bernard equations.
Maximum Likelihood Estimation of Discretely Sampled Diffusions: A Closed‐form Approximation Approach

When a continuous-time diffusion is observed only at discrete dates, in most cases the transition distribution and hence the likelihood function of the observations is not explicitly computable. Using Hermite polynomials, I construct an explicit sequence of closed-form functions and show that it converges to the true (but unknown) likelihood function. I document that the approximation is very accurate and prove that maximizing the sequence results in an estimator that converges to the true maximum likelihood estimator and shares its asymptotic properties. Monte Carlo evidence reveals that this method outperforms other approximation schemes in situations relevant for financial models.
Synchronous dual primary ovarian and endometrial carcinomas

OBJECTIVES: The synchronous occurrence of carcinoma confined to the ovary and endometrium presents a diagnostic and therapeutic dilemma. These tumors have been variously staged as FIG0 Stage IIA ovarian carcinoma, Stage III endometrial carcinoma, or synchronous dual primary carcinomas. Accumulating evidence suggests such patients have a favorable outcome. This retrospective study was undertaken to review our experience with these fascinating tumors. METHODS: The clinical records and the pathologic jindings of 16 patients with synchronous dual primary ovarian and endometrial carcinomas were reviewed. RESULTS: The median age was 51 years. Abnormal uterine bleeding was the most common presenting symptom (70’%). All patients had Stage I ovarian and endometrial carcinomas. Fourteen patients (88%) had endometrioid carcinoma in both sites, while two patients (12%) had dissimilar histology. For 15 patients (94%), the grade of both tumors was identical. Only three (19’%) patients had myometrial invasion, with less than 50% involvement in each case. All patients underwent
Genetic Sensitivity to the Environment: The Case of the Serotonin Transporter Gene and Its Implications for Studying Complex Diseases and Traits

AbstractEvidence of marked variability in response among people exposed to the same environmental risk implies that individual differences in genetic susceptibility might be at work. The study of such Gene-by-Environment (GxE) interactions has gained momentum. In this article, the authors review research about one of the most extensive areas of inquiry: variation in the promoter region of the serotonin transporter gene (SLC6A4; also known as 5-HTT) and its contribution to stress sensitivity. Research in this area has both advanced basic science and generated broader lessons for studying complex diseases and traits. The authors evaluate four lines of evidence about the 5-HTT stress-sensitivity hypothesis: 1) observational studies about the serotonin transporter linked polymorphic region (5-HTTLPR), stress sensitivity, and depression in humans; 2) experimental neuroscience studies about the 5-HTTLPR and biological phenotypes relevant to the human stress response; 3) studies of 5-HTT variation and stress sen...
UV filaments and their application for laser-induced lightning and high-aspect-ratio hole drilling

Experimental results pertaining to 1 ps pulse-width filaments at 248 nm are reviewed. The theoretical studies presented in this paper show that scaling those filaments to ns pulse-widths should enable us to trap up to 1 J in a single channel. We will show how the use of an aerodynamic window can lead to applications such as laser-induced lightning and high-aspect-ratio hole drilling.
Maternal Stress and Preterm Birth

This study examined a comprehensive array of psychosocial factors, including life events, social support, depression, pregnancy-related anxiety, perceived discrimination, and neighborhood safety in relation to preterm birth (<37 weeks) in a prospective cohort study of 1,962 pregnant women in central North Carolina between 1996 and 2000, in which 12% delivered preterm. There was an increased risk of preterm birth among women with high counts of pregnancy-related anxiety (risk ratio (RR) = 2.1, 95% confidence interval (CI): 1.5, 3.0), with life events to which the respondent assigned a negative impact weight (RR = 1.8, 95% CI: 1.2, 2.7), and with a perception of racial discrimination (RR = 1.4, 95% CI: 1.0, 2.0). Different levels of social support or depression were not associated with preterm birth. Preterm birth initiated by labor or ruptured membranes was associated with pregnancy-related anxiety among women assigning a high level of negative impact weights (RR = 3.0, 95% CI: 1.7, 5.3). The association between high levels of pregnancy-related anxiety and preterm birth was reduced when restricted to women without medical comorbidities, but the association was not eliminated. The prospective collection of multiple psychosocial measures on a large population of women indicates that a subset of these factors is associated with preterm birth.
Differentiation of Ex Vivo Human Breast Tissue using Polarization-Sensitive Optical Coherence Tomography

Polarization-sensitive optical coherence tomography (PS-OCT) is sensitive to tissue birefringence. We report development of a high-speed PS-OCT system and imaging of ex vivo human breast tissue, showing contrast between healthy and cancerous tissues.
Design and construction of a first prototype Muon Tomography system with GEM detectors for the detection of nuclear contraband

Current radiation portal monitors at sea ports and international borders that employ standard radiation detection techniques are not very sensitive to nuclear contraband that is well shielded to absorb emanating radiation. Muon Tomography (MT) based on the measurement of multiple scattering of atmospheric cosmic ray muons traversing cargo or vehicles that contain high-Z material is a promising passive interrogation technique for solving this problem. We report on the design and construction of compact Micro-Pattern Gas Detectors for a small prototype MT station. This station will employ 10 tracking stations based on 30cm × 30cm low-mass triple-GEM detectors with 2D readout. Due to the excellent spatial resolution of GEMs it is sufficient to use a gap of only a few cm between tracking stations. Together with the compact size of the GEM detectors this allows the GEM MT station to be an order of magnitude more compact than MT stations using traditional drift tubes. We present details of the production and assembly of the GEM-based tracking stations in collaboration with CERN and the RD51 collaboration as well as the design of the initial front-end electronics and readout system.
Capacity analysis for continuous-alphabet channels with side information, part I: a general framework

Capacity analysis for channels with side information at the receiver has been an active area of interest. This problem is well investigated for the case of finite-alphabet channels. However, the results are not easily generalizable to the case of continuous-alphabet channels due to analytical difficulties inherent with continuous alphabets. In the first part of this two-part paper, we address an analytical framework for capacity analysis of continuous alphabet channels with side information at the receiver. For this purpose, we establish novel necessary and sufficient conditions for weak* continuity and strict concavity of the mutual information. These conditions are used in investigating the existence and uniqueness of the capacity-achieving measures. Furthermore, we derive necessary and sufficient conditions that characterize the capacity value and the capacity-achieving measure for continuous-alphabet channels with side information at the receiver.
Understanding the City Size Wage Gap

In 2000, wages of full time full year workers were more than 30 percent higher in metropolitan areas of over 1.5 million people than rural areas. The monotonic relationship between wages and city size is robust to controls for age, schooling and labor market experience. In this paper, we decompose the city size wage gap into various components. We propose an on-the-job search model that incorporates latent ability, search frictions, firm-worker match quality, human capital accumulation and endogenous migration between large, medium and small cities. Counterfactual simulations of the model indicate that variation in returns to experience and differences in wage intercepts across location type are the most important mechanisms contributing to the overall city size wage premium. Steeper returns to experience in larger cities is more important for college graduates while differences in wage intercepts is more important for high school graduates. Sorting on unobserved ability within education group and differences in labor market search frictions and distributions of firm-worker match quality contribute little or slightly negatively to observed city size wage premia in both samples.
Evolving Reusable Neural Modules

Topology and Weight Evolving Artificial Neural Networks (TWEANNs) have been shown to be powerful in nonlinear optimization tasks such as double pole-balancing. However, if the input, output, or network structures are high dimensional, the search space may be too large to search efficiently. If the symmetries inherent in many large domains were correctly identified and used to break the problem down into simpler sub-problems (to be solved in parallel), evolution could proceed more efficiently, spending less time solving the same sub-problems more than once. In this paper, a coevolutionary modular neuroevolution method, Modular NeuroEvolution of Augmenting Topologies (Modular NEAT), is developed that automatically performs this decomposition during evolution. By reusing neural substructures in a scalable board game domain, modular solution topologies arise, making evolutionary search more efficient.
The Via Lactea INCITE simulation: Galactic dark matter substructure at high resolution

It is a clear and unique prediction of the cold dark matter paradigm of cosmological structure formation that galaxies form hierarchically and are embedded in massive, extended dark halos teeming with self-bound substructure, or 'subhalos.' The amount and spatial distribution of subhalos around their host provide unique information and clues on the galaxy assembly process and the nature of the dark matter. Here we present results from the Via Lactea INCITE simulation, a one billion particle, one million CPU-hour simulation of the formation and evolution of a galactic dark matter halo and its substructure population.
Posets with Cover Graph of Pathwidth two have Bounded Dimension

Joret, Micek, Milans, Trotter, Walczak, and Wang recently asked if there exists a constant d such that if P is a poset with cover graph of P of pathwidth at most 2, then dim(P ) ≤ d. We answer this question in the affirmative by showing that d = 17 is suffi- cient. We also show that if P is a poset containing the standard example S5 as a subposet, then the cover graph of P has treewidth at least 3.
Small-scale irrigation dams, agricultural production, and health - theory and evidence from Ethiopia

The author looks at the feasibility and potential of instituting small-scale irrigation dams to reduce Ethiopias dependence on rainfed agriculture and the associated food insecurity. He develops a theoretical framework to assess the welfare implications of irrigation development programs and provides empirical evidence from microdam construction and reforestation projects in northern Ethiopia. The author pays particular attention to health-related costs of establishing small-scale irrigation dams in areas prone to waterborne diseases. While the theoretical analyses imply that the net welfare impacts of irrigation dams cannot be known a priori due to potential health costs, the empirical evidence shows that current agricultural yield and farm profit have increased in villages with closer proximity to the dams than in those more distant. The increased disease incidence due to standing pools of water has, however, led to significant declines in the returns from investment in irrigation water. Households with poor health are less likely to adopt productivity-enhancing as well as resource-conserving technologies, which are crucial for achieving the ultimate goal of sustainable agricultural development. The ensuing sickness has also led to reduction in labor allocation to off-farm activities. The findings underline the importance of weighing beforehand the magnitude of potential economic benefits against health costs of water development programs. The overall evidence, however, suggests that carefully designed irrigation dams could significantly improve agricultural production and food security, particularly in areas where waterborne diseases pose negligible risk to health or can be cost-effectively controlled.
Estimating far-field errors due to mechanical errors in spherical near-field scanning

When the mechanical requirements are established for a spherical near-field scanner, it is desirable to estimate what effects the expected mechanical errors will have on the determination of the far field of potential antennas that will be measured on the proposed range. The National Institute of Standards and Technology (NIST) has investigated the effects of mechanical errors for a proposed outdoor spherical near-field range to be located at Ft. Huachuca, AZ. This investigation was performed by use of theoretical far-field patterns and introducing position errors into simulated spherical near-field measurements. Far-field patterns were then calculated with and without probe-position correction to determine the effects of mechanical position errors. This paper reports the results of these investigations.
Stop the Top Background of the Stop Search

The main background for the supersymmetric stop direct production search comes from Standard Model $ t\overline t $ events. For the single-lepton search channel, we introduce a few kinematic variables to further suppress this background by focusing on its dileptonic and semileptonic topologies. All are defined to have end points in the background, but not signal distributions. They can substantially improve the stop signal significance and mass reach when combined with traditional kinematic variables such as the total missing transverse energy. Among them, our variable $ M_{{T2}}^W $ hasthebestoverallperformancebecause it uses all available kinematic information, including the on-shell mass of both W’s. We see 20 %-30 % improvement on the discovery significance and estimate that the 8 TeV LHC run with 20 fb−1 of data would be able to reach an exclusion limit of 650-700 GeV for direct stop production, as long as the stop decays dominantly to the top quark and a light stable neutralino. Most of the mass range required for the supersymmetric solution of the naturalness problem in the standard scenario can be covered.
Modeling network dynamics: the lac operon, a case study

We use the lac operon in Escherichia coli as a prototype system to illustrate the current state, applicability, and limitations of modeling the dynamics of cellular networks. We integrate three different levels of description (molecular, cellular, and that of cell population) into a single model, which seems to capture many experimental aspects of the system.
Electron photoejection and its application in studies of electron transfers

The principle of electron photoejection technique is explained. This approach leads to the formation of transient spectra of unstable intermediates, allowing their recording and providing their extinction coefficients. Moreover, it permits determination of their electron affinities and the rates of their reactions, whether spontaneous or with some added substrates. Application of this technique to studies of disproportionation of radical anions have been most profitable. It led to the determination of the forward and backward rate constants of disproportionation of a variety of radical anions, and to discovery and quantification of some subtle features of these reactions. Electron photoejection technique provided the data characterizing the electron transfer initiation of anionic polymerization and clarified some of its features. Other opportunities provided by the electron photoejection in studies on electron transfer processes are suggested.
An overview of Sandia National Laboratories' plasma switched, gigawatt, ultra-wideband impulse transmitter program

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source technology and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting depending on how the UWB frequency components are generated. The frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability.
New methodology for reducing sensor and readout electronics circuitry noise in digital domain

Upcoming NASA cosmology science missions, such as Joint Dark Energy Mission (JDEM), carry instruments with multiple focal planes populated with many large sensor detector arrays. These sensors are passively cooled to low temperatures for low-level light (L3) and near-infrared (NIR) signal detection [2], and the sensor readout electronics circuitry must perform at extremely low noise levels to enable new required science measurements. Because we are at the technological edge of enhanced performance for sensors and readout electronics circuitry, as determined by thermal noise level at given temperature in analog domain, we must find new ways of further compensating for the noise in the signal digital domain. To facilitate this new approach, state-of-the-art sensors are augmented at their array hardware boundaries by non-illuminated reference pixels, which can be used to reduce noise attributed to sensor and readout electronics. There are a few proposed methodologies of processing in the digital domain the information carried by reference pixels, as employed, for example, by the James Webb Space Telescope Project (JWST). These methods involve using spatial and temporal statistical parameters derived from boundary reference pixel information to enhance the active pixels' signals. To make a step beyond this heritage methodology, we apply the NASA-developed technology known as the Hilbert-Huang Transform Data Processing System (HHT-DPS) to some component of reference pixel information. The new methodology applies digital signal processing for a 2-D domain. The high-variance components of the thermal noise, carried by both active and reference pixels, facilitate subtraction of a correction matrix from active pixels array in digital domain in addition to subtraction of a single analog reference pixel from all active pixels on the sensor. Heritage methods using the statistical parameters in the digital domain (such as statistical averaging of the reference pixels) zero out the high-variance components, and the counterpart components in the active pixels remain uncorrected. This paper describes how the new methodology was demonstrated through analysis of fast varying noise components using the HHT-DPS and makes the case for re-implementation of HHT-DPS in reconfigurable hardware on-board a spaceflight instrument as a real-time processing system (RT-HHT-DPS) [1].
A Groupoid Approach to Noncommutative T-Duality

Topological T-duality is a transformation taking a gerbe on a principal torus bundle to a gerbe on a principal dual-torus bundle. We give a new geometric construction of T-dualization, which allows the duality to be extended in the following two directions. First, bundles of groups other than tori, even bundles of some nonabelian groups, can be dualized. Second, bundles whose duals are families of noncommutative groups (in the sense of noncommutative geometry) can be treated, though in this case the base space of the bundles is best viewed as a topological stack. Some methods developed for the construction may be of independent interest. These are a Pontryagin type duality that interchanges commutative principal bundles with gerbes, a nonabelian Takai type duality for groupoids, and the computation of certain equivariant Brauer groups.
Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women: The A TO Z Weight Loss Study: A Randomized Trial

ContextPopular diets, particularly those low in carbohydrates, have challenged current recommendations advising a low-fat, high-carbohydrate diet for weight loss. Potential benefits and risks have not been tested adequately.ObjectiveTo compare 4 weight-loss diets representing a spectrum of low to high carbohydrate intake for effects on weight loss and related metabolic variables.Design, Setting, and ParticipantsTwelve-month randomized trial conducted in the United States from February 2003 to October 2005 among 311 free-living, overweight/obese (body mass index, 27-40) nondiabetic, premenopausal women.InterventionParticipants were randomly assigned to follow the Atkins (n = 77), Zone (n = 79), LEARN (n = 79), or Ornish (n = 76) diets and received weekly instruction for 2 months, then an additional 10-month follow-up.Main Outcome MeasuresWeight loss at 12 months was the primary outcome. Secondary outcomes included lipid profile (low-density lipoprotein, high-density lipoprotein, and non–high-density lipoprotein cholesterol, and triglyceride levels), percentage of body fat, waist-hip ratio, fasting insulin and glucose levels, and blood pressure. Outcomes were assessed at months 0, 2, 6, and 12. The Tukey studentized range test was used to adjust for multiple testing.ResultsWeight loss was greater for women in the Atkins diet group compared with the other diet groups at 12 months, and mean 12-month weight loss was significantly different between the Atkins and Zone diets (P<.05). Mean 12-month weight loss was as follows: Atkins, −4.7 kg (95% confidence interval [CI], −6.3 to −3.1 kg), Zone, −1.6 kg (95% CI, −2.8 to −0.4 kg), LEARN, −2.6 kg (−3.8 to −1.3 kg), and Ornish, −2.2 kg (−3.6 to −0.8 kg). Weight loss was not statistically different among the Zone, LEARN, and Ornish groups. At 12 months, secondary outcomes for the Atkins group were comparable with or more favorable than the other diet groups.ConclusionsIn this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight and experienced more favorable overall metabolic effects at 12 months than women assigned to follow the Zone, Ornish, or LEARN diets. While questions remain about long-term effects and mechanisms, a low-carbohydrate, high-protein, high-fat diet may be considered a feasible alternative recommendation for weight loss.Trial Registrationclinicaltrials.gov Identifier: NCT00079573
Sensitivity analysis of seismic reflectivity to partial gas saturation

We analyze the sensitivity of seismic reflectivity to contrasts in density, seismic propagation velocities, Poisson’s ratio, and gas saturation using the complete Zoeppritz equations. Sensitivities of reflection coefficients to each bulk elastic parameter are computed as the partial derivatives of the seismic reflectivities, relative to each parameter. The sensitivity of reflectivity to gas saturation is then calculated as the full derivative of the reflectivities with respect to gas saturation, assuming both a homogeneous and a patchy distribution of gas in the pore fluids. We compute sensitivities for a sealing shale/gas-sand interface and a gas-sand/wet-sand (gas-water contact, GWC) interface. For the SH-SH reflectivity, the effect of density contrast is strongest in the 30°–50° range of incidence angles for the fluid-fluid interface and at nearer offsets for the shale/gas-sand interface. P-SV reflectivity forthe fluid-fluid interfaces is more sensitive to density contrast in the range of angles of inc...
1-Amido-3-(1H)-1,2-benziodoxoles: Stable Amidoiodanes and Reagents for Direct Amidation of Organic Substrates.

Abstract Amidobenziodoxoles 2 can be prepared from benziodoxole 1 , trimethylsilyltriflate and the appropriate amides in the form of stable, microcrystalline compounds. Amidobenziodoxoles 2 react with adamantane 3 or N , N -dimethylarylamines 5 to afford the corresponding products of amidation, 4 and 6 .
Gas molecule adsorption in carbon nanotubes and nanotube bundles

We studied various gas molecules (NO2, O2, NH3, N2, CO2, CH4, H2O, H2, Ar) on single-walled carbon nanotubes (SWNTs) and bundles using first principles methods. The equilibrium position, adsorption energy, charge transfer, and electronic band structures are obtained for different kinds of SWNTs. Most molecules adsorb weakly on SWNTs and can be either charge donors or acceptors to the nanotubes. We find that the gas adsorption on the bundle interstitial and groove sites is stronger than that on individual nanotubes. The electronic properties of SWNTs are sensitive to the adsorption of certain gases such as NO2 and O2. Charge transfer and gas-induced charge fluctuation might significantly affect the transport properties of SWNTs. Our theoretical results are consistent with recent experiments.
Static analysis of real-time distributed systems

A static analysis for reasoning about the temporal behaviors of programs in real-time distributed programming languages is proposed. The analysis is based on the action set semantics using the pure maximal parallelism model. It is shown how to specify and verify various timing properties of real-time programs. The approach provides only an approximate timing behavior, because the state information is ignored. However, many interesting properties such as parallel actions, deadlocks, livelocks, terminations, temporal errors, and failures, can be identified. Furthermore, the approach is compositional and thus makes it possible to reason about the timing properties incrementally. The method not only leads to efficient algorithms for the static analysis of CSP programs but also applies to many other languages. >
On Rereading Haavelmo: A Retrospective View of Econometric Modeling

The main aim of the paper is to reevaluate the methodological contributions of Tinbergen and Haavelmo in the context of the current discussions on econometric modeling and propose a reformulation of the Haavelmo methodology. The paper argues that the textbook methodology constitutes a less flexible version of Tinbergen's approach and apart from the probabilistic language, it has little in common with the methodology in Haavelmo's 1944 monograph, commonly acknowledged as having founded modern econometrics. The methodology in this monograph includes several important elements which have either been discarded or never fully integrated within the textbook approach. A re-synthesis of these elements gives rise to an alternative methodological framework. This framework can be used to meet most of the objections to the textbook methodology and provides a framework in the context of which the recent methodological controversies can be evaluated.
A History of Aesthetics from Homer to Digital Mash-ups: Cumulative Creativity and the Demise of Copyright Exclusivity

Under a regime of limited economic incentive for creativity and confined commodification of information, humanity produced the greatest portion of human knowledge. To mention some, the Bible, the Qur'an, the Mahābhārata, the Iliad and Odyssey, the Aeneid, the Scandinavian Sagas, the German Lay of the Nibelungs, the Celtic legends of Arthur, the Romances and Chanson De Geste all came to life well before strong economic rights were attached to creativity. Later, Petrarch declaimed the Dolce Stil Novo, Dante wrote the Divina Commedia, Chaucer fathered English literature, Ludovico Ariosto chanted Orlando Furioso, Cervantes unleashed his Don Quixote de la Mancha against windmills and earlier epic literature, and Shakespeare gave immortal life to the love of Romeo and Juliet. Emulation, imitation, plagiarism, borrowing, remixing and recombination had a constant demiurgic power in the history of creativity. However, modern policies have largely forgotten the cumulative and collaborative nature of creativity. In ...
Beyond time-frequency analysis: energy densities in one and many dimensions

Given a unitary operator A representing a physical quantity of interest, we employ concepts from group representation theory to define two natural signal energy densities for A. The first is invariant to A and proves useful when the effect of A is to be ignored; the second is covariant to A and measures the "A" content of signals. We also consider joint densities for multiple operators and, in the process, provide an alternative interpretation of Cohen's (see Englewood Cliffs, NJ: Prentice-Hall, 1995) general construction for joint distributions of arbitrary variables.
An Efficient Data Partitioning Method for Limited Memory Embedded Systems

In this work we propose a framework to carry out an efficient data partitioning for arrays on limited memory embedded systems. We introduce a concept of footprint to precisely calculate the memory demands of references and compute a profit value of a reference using its access frequency and reuse factor. We then develop a methodology based on 0/1 knapsack algorithm to partition the references in local/remote memory. We show the performance improvements due to our approach and compare the results.
General forms and properties of zero cross-correlation radar waveforms

General forms for both the complementary and noncomplementary zero cross-correlation waveform sets are developed. Various properties of these codes and their relationship to zero sidelobe periodic codes are stated and proved. Some radar applications and practical considerations of using these codes are briefly discussed. >
Total synthesis of octalactin A via ring-closing metathesis reaction

A new total synthesis of the novel lactone natural product octalactin A is described. The key step involves the facile construction of the eight-membered lactone core via ring-closing metathesis (RCM). This oxocene was elaborated to give the powerful antitumor agent octalactin A.
CASE: a program for simulation of concept learning

The Learning Research and Development Center of the University of Wisconsin is engaged in a long-term multifacet study of concept learning, supported by the U.S. Office of Education. The Concept Attainment Simulation Experiment (CASE) is the facet of this overall effort which utilizes the technology of computer simultation as a vehicle for obtaining a better understanding of the psychological processes involved in the learning of concepts. The long-range goal is the utilization of the insights thus obtained to improve classroom learning. The study of concept learning has a long history within psychology and has received considerable attention in recent years due in part to the book by Bruner, Goodnow, and Austin which delineated strategies for learning concepts. The experimental materials used by Bruner consisted of a finite universe of objects each of which possessed n dimensions; and each dimension could assume k different values. A classification rule (a concept), consisting of a particular combination of dimension values, partitioned the universe into two mutually exclusive sets. In a typical experiment a subject was shown an object which was an exemplar of the set defined by the concept and told his task was to ascertain the classification rule. In order to attain the concept the subject chose objects from the universe and the experimenter indicated the set membership of the object chosen. The object selection-designation procedure continued until the subject could verbalize the correct classification rule and hence the concept had been attained. The experimental situation, the problem to be solved, and learning procedure involved appear reasonably simple and a number of persons have written programs to simulate this type learning experiment---Hunt and Hovland, Hunt, Allen, Wickelgren, and Baker. The book by Hunt provides an excellent review of much of the psychological literature relevant to concept learning as well as a discussion of his own simulation program. Unfortunately the existing programs leave one with the disquieting feeling that although they attain concepts, little has been added to our understanding of the psychological processes involved in concept learning. Most of these programs are at best watered-down algorithms and involve very little of psychological importance. Because of the shortcomings of the existing simulation programs a project was initiated to develop a program which hopefully will eventuate in something of psychological significance.
Accuracy of an atomic microwave power standard

We have built an atomic microwave power standard based on the electromagnetic interaction with laser-cooled atoms. The atoms traversed a waveguide transmission line, and under the effect of the radiation, the internal state populations underwent a Rabi flopping oscillation. Measurement of the oscillation frequency allowed the determination of the incident microwave power. As many of 60 oscillations were observed over a dynamic range of 20 dB and the standard deviation of the measurements was about 0.02%. The measured frequency was compared to a calculated one and an agreement of 1.3% with an uncertainty of 5% (rectangular) was found.
Single-cell transcriptomics reveals bimodality in expression and splicing in immune cells

Recent molecular studies have revealed that, even when derived from a seemingly homogenous population, individual cells can exhibit substantial differences in gene expression, protein levels, and phenotypic output 1–5 , with important functional consequences 4,5 . Existing studies of cellular heterogeneity, however, have typically measured only a few pre-selected RNAs 1,2 or proteins 5,6 simultaneously because genomic profiling methods 3 could not be applied to single cells until very recently 7–10 . Here, we use single-cell RNA-Seq to investigate heterogeneity in the response of bone marrow derived dendritic cells (BMDCs) to lipopolysaccharide (LPS). We find extensive, and previously unobserved, bimodal variation in mRNA abundance and splicing patterns, which we validate by RNA-fluorescence in situ hybridization (RNA-FISH) for select transcripts. In particular, hundreds of key immune genes are bimodally expressed across cells, surprisingly even for genes that are very highly expressed at the population average. Moreover, splicing patterns demonstrate previously unobserved levels of heterogeneity between cells. Some of the observed bimodality can be attributed to closely related, yet distinct, known maturity states of BMDCs; other portions reflect differences in the usage of key regulatory circuits. For example, we identify a module of 137 highly variable, yet co-regulated, antiviral response genes. Using cells from knockout mice, we show that variability in this module may be propagated through an interferon feedback circuit involving the transcriptional regulators Stat2 and Irf7. Our study demonstrates the power and promise of single-cell genomics in uncovering functional diversity between cells and in deciphering cell states and circuits.
Additive approximation for edge-deletion problems

A graph property is monotone if it is closed under removal of vertices and edges. In this paper we consider the following algorithmic problem, called the edge-deletion problem; given a monotone property P and a graph G, compute the smallest number of edge deletions that are needed in order to turn G into a graph satisfying P. We denote this quantity by E' P (G). The first result of this paper states that the edge-deletion problem can be efficiently approximated for any monotone property. • For any fixed e > 0 and any monotone property P, there is a deterministic algorithm which, given a graph G = (V, E) of size n, approximates E' P (G) in linear time O(|V| + |E|) to within an additive error of en 2 . Given the above, a natural question is for which monotone properties one can obtain better additive approximations of E' P . Our second main result essentially resolves this problem by giving a precise characterization of the monotone graph properties for which such approximations exist. (1) If there is a bipartite graph that does not satisfy P, then there is a δ > 0 for which it is possible to approximate E' P to within an additive error of n 2 -δ in polynomial time. (2) On the other hand, if all bipartite graphs satisfy P, then for any δ > 0 it is NP-hard to approximate E' P to within an additive error of n 2-δ . While the proof of (1) is relatively simple, the proof of (2) requires several new ideas and involves tools from Extremal Graph Theory together with spectral techniques. Interestingly, prior to this work it was not even known that computing E' P precisely for the properties in (2) is NP-hard. We thus answer (in a strong form) a question of Yannakakis, who asked in 1981 if it is possible to find a large and natural family of graph properties for which computing E' P is NP-hard.
Quantum Dots-Enabled High-Resolution Analysis of Gene Copy Number Variation

We have developed a novel quantum dot (QD)-enabled copy number variation (CNV) quantification assay. Current CNV detection techniques are not able to reliably quantify less than a twofold difference. The assay employed a QD to physically transform the target copy number into different electrophoretic mobility (EM) levels that could be assessed by the electrophoresis. We built a model to predict the electrophoretic migration and explain the band broadening of the QD-DNA nanocomplex. The nanoassay demonstrated a remarkable resolution, capable of distinguishing a Li fold (~9%) difference in the target copy number. We applied the nanoassay to detect the CNV of the Rsf-1 gene that plays an important role in ovarian cancer.
Computer Languages for Symbol Manipulation

Complex, flexible, computer programs can be written easily in list-processing languages. Storage registers are linked together in arbitrary sequences to form lists and list structures, which are the units of the languages. Special provisions are made for recursive subroutines and for hierarchical programs. These particular languages have been used to write game-playing, problem-solving, and other ``intelligent'' Programs.
The Productivity Slowdown: Is a Growing Unmeasurable Sector the Culprit?

The productivity slowdown of the early 1970s continues to puzzle economists. A frequent explanation of this puzzle is that mismeasurement of output has worsened enough to help account for the apparent shortfall of output growth. Griliches (1994) highlighted one channel through which this worsening measurement could occur. He raised the possibility that—because output growth in the service sector likely is undermeasured—the rising share of services has led to greater undermeasurement of overall economic growth. This paper demonstrates that this argument is of little quantitative significance. Even under assumptions most favorable to the hypothesis, the rising share of services has had only a small impact on measurement error. These results—along with evidence from Baily and Gordon (1988)—make mismeasurement of output an improbable explanation for the productivity slowdown in aggregate data.
A Mild, One-Pot Synthesis of 4-Quinolones via Sequential Pd-Catalyzed Amidation and Base-Promoted Cyclization†

A mild, one-pot synthesis of 4-quinolones is described. Under the optimal conditions, a variety of 2-substituted 4-quinolones were synthesized via sequential palladium-catalyzed amidation of 2′-bromoacetophenones followed by base-promoted intramolecular cyclization.
Structural design issues for electromagnetic projectiles

Many structural design issues associated with electromagnetic launch of projectiles will respond to the same techniques as used for conventional gun launch. The methods used to assess and manage the loads associated with the axial propulsive force (tapered sabots), with rapid propulsive rise time (dynamic finite-element analysis), and with transverse balloting loads (coupled projectile/gun models) are interpreted for high-velocity, electromagnetically accelerated projectiles. Some conclusions from these conventional interior ballistic technologies are offered for the designer. >
The grid protocol: a high performance scheme for maintaining replicated data

A new protocol for maintaining replicated data that can provide both high data availability and low response time is presented. In the protocol, the nodes are organized in a logical grid. Existing protocols are designed primarily to achieve high availability by updating a large fraction of the copies, which provides some (although not significant) load sharing. In the new protocol, transaction processing is shared effectively among nodes storing copies of the data, and both the response time experienced by transactions and the system throughput are improved significantly. The authors analyze the availability of the new protocol and use simulation to study the effect of load sharing on the response time of transactions. They also compare the new protocol with a voting-based scheme. >
Graded-channel MOSFET (GCMOSFET) for high performance, low voltage DSP applications

Graded-Channel MOS (GCMOS) VLSI technology has been developed to meet the growing demand for low power and high performance applications. In this paper, it will be shown that, compared to conventional complementary metal-oxide-semiconductor (CMOS), the GCMOS device offers the advantage of significantly higher drive current, capable of lower threshold voltage with improved punchthrough resistance, lower body effect and lower series resistance, thus making it most suitable for applications that require both high performance and low power consumption, such as digital signal processing (DSP). This is demonstrated, for the first time, by much improved low voltage circuit performance of a DSP logic circuit fabricated using a 0.5 /spl mu/m GCMOS process. At 1.8 V, a 30% speed improvement over CMOS is achieved, and the power-delay product is reduced by 25%. In addition, similar speed improvement is achieved in SRAM's with consistent performance improvement over a wide range of temperatures between -50 and 150/spl deg/C.