cssi/SciSciGPT-SciSciNet huggingface dataset:
Tunneling gap as evidence for time-reversal symmetry breaking at surfaces of high-temperature superconductors

Abstract It is argued that recent Josephson junction and point-contact tunneling experiments, interpreted as intended by their authors, indicate that time0reversal symmetry breaking occurs at surfaces of cuprate superconductors. The variation among experiments and the failure of previous searches to find T violation are ascribed to disorder and effects of three-dimensionality. The anyon approach to the t-J model is shown to predict a conventional BCS order parameter of d x 2 − y 2 + iϵd xy symmetry, with ϵ roughly 3 times the doping fraction δ, which is consistent with these experiments but not demonstrated by them.
The future of strategic studies: Beyond even grand strategy

(1992). The future of strategic studies: Beyond even grand strategy. The Round Table: Vol. 81, No. 322, pp. 135-152.
Conformational preference of cis-1-aryl-2-(2-benzo[C]phenanthryl)-and cis-1-aryl-2-(3-phenanthryl)-ethenes

NMR measurements under different conditions (temperature, solvents used, presence of a shift-reagent) of cis- and trans-1-aryl-2-(2-benzo[c]phenanthryl)-ethenes reveal that an overcrowded conformation predominates in cis isomers. In the analogous 1-aryl-2-(3-phenanthryl)ethenes no clear conformational preference is found.
Evaluation of Boundary Conditions for the Gust-Cascade Problem

Using a high-order accuracy finite-difference time-domain algorithm, the acoustic scattering from a flat-plate cascade is computed. Keeping the grid and time step fixed, the effect of four different boundary conditions on the accuracy and stability of the computed solution is compared.
With the help of one's neighbors - externalities in the production of nutrition in Peru

Both public, and private resources contribute to children's nutritional status. And investments by one household may improve health in other neighborhood households, by improving the sanitation environment, and increasing shared knowledge. The authors measure the externalities of investments in nutrition, by indicating the impact of women's education in Peruvian neighborhoods, on children's nutrition in other households, after controlling for those households' education, and income. They find that in rural areas this shared knowledge has a significant impact on nutrition. The coefficient of an increase in the average education in the neighborhood is appreciably larger than the coefficient of education in isolation. That is, educating women in rural areas, improves all children's nutritional status, even for those whose caregivers are themselves not educated. In both urban, and rural areas, they observe externalities from investments in sanitation made by neighboring households. They do not find the same externalities in the case of investments, only in the household water supply. There is a direct link between the caregivers' education, and their children's health status. Education transmits information about health, and nutrition. It teaches numeracy, and literacy, which help caregivers read labels, and instructions. Bu exposing caregivers to new environments, it makes them receptive to modern medical treatment. It gives women the confidence to participate in decision-making within a household, and it gives men, and women the confidence to interact with health care professionals.
Optimizing scrip systems: crashes, altruists, hoarders, sybils and collusion

Scrip, or artificial currency, is a useful tool for designing systems that are robust to selfish behavior by users. However, it also introduces problems for a system designer, such as how the amount of money in the system should be set. In this paper, the effect of varying the total amount of money in a scrip system on efficiency (i.e., social welfare—the total utility of all the agents in the system) is analyzed, and it is shown that by maintaining the appropriate ratio between the total amount of money and the number of agents, efficiency is maximized. This ratio can be found by increasing the money supply to just below the point that the system would experience a “monetary crash,” where money is sufficiently devalued that no agent is willing to perform a service. The implications of the presence of altruists, hoarders, sybils, and collusion on the performance of the system are examined. Approaches are discussed to identify the strategies and types of agents.
Spatial distribution and motion of the known asteroids.

Spatial distribution and motion of known asteroids analyzed in order to avoid or maximize encounters in planning space flight
the impact of the Rapid City flood on public opinion about weather modification

Prior to the Rapid City flood of 9 June 1972, a panel of South Dakota respondents had participated in a sociological survey on opinion about weather modification. The panel was reinterviewed after the event. Findings show that most respondents were aware that cloud seeding had occurred prior to the flood, that the majority did not attribute the flood to cloud seeding, that Rapid City area residents were no more likely than other respondents to attribute a causal link, and that the perception of the disaster as man-made is associated with increased awareness and belief that the technology is effective and decreased favorability toward the technology and toward programs. No organized opposition to weather modification has occurred in South Dakota since the flood.
DIRECT NUMERICAL SIMULATION OF RADIATION PRESSURE-DRIVEN TURBULENCE AND WINDS IN STAR CLUSTERS AND GALACTIC DISKS

The pressure exerted by the radiation of young stars may be an important feedback mechanism that drives turbulence and winds in forming star clusters and the disks of starburst galaxies. However, there is great uncertainty in how efficiently radiation couples to matter in these high optical depth environments. In particular, it is unclear what levels of turbulence the radiation can produce, and whether the infrared radiation trapped by the dust opacity can give rise to heavily mass-loaded winds. In this paper, we report a series of two-dimensional flux-limited diffusion radiation-hydrodynamics calculations performed with the code ORION in which we drive strong radiation fluxes through columns of dusty matter confined by gravity in order to answer these questions. We consider both systems where the radiation flux is sub-Eddington throughout the gas column, and those where it is super-Eddington at the midplane but sub-Eddington in the atmosphere. In the latter, we find that the radiation-matter interaction gives rise to radiation-driven Rayleigh-Taylor instability, which drives supersonic turbulence at a level sufficient to fully explain the turbulence seen in Galactic protocluster gas clouds, and to make a non-trivial contribution to the turbulence observed in starburst galaxy disks. However, the instability also produces a channel structure in which the radiation-matter interaction is reduced compared to time-steady analytic models because the radiation field is not fully trapped. For astrophysical parameters relevant to forming star clusters and starburst galaxies, we find that this effect reduces the net momentum deposition rate in the dusty gas by a factor of ~2-6 compared to simple analytic estimates, and that in steady state the Eddington ratio reaches unity and there are no strong winds. We provide an approximation formula, appropriate for implementation in analytic models and non-radiative simulations, for the force exerted by the infrared radiation field in this regime.
Ultrahigh-energy neutrino–nucleon cross sections and perturbative unitarity

Abstract Unitarity relates the total cross section for neutrino–nucleon scattering to the neutrino–nucleon forward scattering amplitude. Assuming the validity of the perturbative expansion of the forward amplitude in the weak coupling constant, we derive a unitarity bound on the inelastic cross section. The inelastic cross section saturates this bound at a typical neutrino energy E ν ≃10 8 GeV. This implies that calculations of the inelastic cross section that use current parton distribution functions and lowest order weak perturbation theory are unreliable above this energy.
A contact-waiting-time metric and RNA folding rates.

Abstract Metrics for indirectly predicting the folding rates of RNA sequences are of interest. In this letter, we introduce a simple metric of RNA structural complexity, which accounts for differences in the energetic contributions of RNA base contacts toward RNA structure formation. We apply the metric to RNA sequences whose folding rates were previously determined experimentally. We find that the metric has good correlation (correlation coefficient: −0.95, p ≪ 0.01 ) with the logarithmically transformed folding rates of those RNA sequences. This suggests that the metric can be useful for predicting RNA folding rates. We use the metric to predict the folding rates of bacterial and eukaryotic group II introns. Future applications of the metric (e.g., to predict structural RNAs) could prove fruitful.
Transvaginal ultrasonographic characterization of ovarian masses by means of color flow-directed Doppler measurements and a morphologic scoring system.

OBJECTIVE: The aim of the study was to test the hypothesis that a combination of a previously devised morphologic scoring system and color flow-directed Doppler measurements would afford better discrimination between benign and malignant ovarian masses. STUDY DESIGN: The scoring system and color flow-directed Doppler measurements for 115 masses were prospectively analyzed and correlated with histopathologic surgical findings. RESULTS: In 21 masses (18 patients) no flow was obtained. Seventy-eight masses in 70 patients were benign, and 16 masses in 12 patients were malignant. The mean total score for the benign masses was 6.7 and for the malignant masses 11.7. The resistance index was 0.64 for the benign lesions and 0.39 for the malignant masses (range 0.2 to 0.98). The mean pulsatility index of the benign masses was 1.17 and 0.52 for the malignancies (range 0.2 to 2.6). There were no malignancies in the group with no flow obtained. The sensitivity and specificity of score alone was 94% and 87%, respectively, with a 60% positive predictive value. By means of resistance index or pulsatility index the sensitivity was 94%, the specificity 99%, and the positive predictive value 94%. CONCLUSION: These results suggest that Doppler flow measurements alone and in conjunction with a scoring system help differentiate benign from malignant masses.
Astronomical archives of the future: a virtual observatory

Abstract Astronomy is entering a new era as multiple, large area, digital sky surveys are in production. The resulting datasets are truly remarkable in their own right; however, a revolutionary step arises in the aggregation of complimentary multi-wavelength surveys (i.e. the cross-identification of a billion sources). Federating these different datasets, however, is an extremely challenging task. With this task in mind, we have identified several areas where community standardization can provide enormous benefits in order to develop the techniques and technologies necessary to solve the problems inherent in federating these large databases, as well as the mining of the resultant aggregate data. Several of these areas are domain specific, however, the majority of them are not. We feel that the inclusion of non-astronomical partnerships can provide tremendous insights.
Identification of Structural Dynamics Models Using Wavelet-Generated Impulse Response Data

This paper addresses the use of discrete wavelet transforms for the identification of structural dynamics models. First, the discrete temporal impulse response functions are obtained from vibration records by the discrete wavelet transform (DWT). They are then utilized for system realizations. From the realized state space models, structural modes, mode shapes and damping parameters are extracted. Attention has been focused on a careful comparison of the present DWT system identification approach to the FFT-based approach. Numerical examples demonstrate that the present DWT-based structural system identification procedure is a serious alternative to the FFT-based procedure, and outperforms FFT methods for narrow frequency-band inputs.
Biomimicry in metal-organic materials

Abstract Nature has evolved a great number of biological molecules which serve as excellent constructional or functional units for metal–organic materials (MOMs). Even though the study of biomimetic MOMs is still at its embryonic stage, considerable progress has been made in the past few years. In this critical review, we will highlight the recent advances in the design, development and application of biomimetic MOMs, and illustrate how the incorporation of biological components into MOMs could further enrich their structural and functional diversity. More importantly, this review will provide a systematic overview of different methods for rational design of MOMs with biomimetic features.
An experiment for determining the Euler load by direct computation

A direct algorithm is presented for computing the Euler load of a column from experimental data. The method is based on exact inextensional theory for imperfect columns, which predicts two distinct deflected shapes at loads near the Euler load. The bending stiffness of the column appears in the expression for the Euler load along with the column length; therefore, the experimental data allow a direct computation of bending stiffness. Experiments on graphite-epoxy columns of rectangular cross section are reported in the paper. The bending stiffness of each composite column computed from experiment is compared with predictions from laminated plate theory.
Automated bug isolation via program chipping

This paper introduces program chipping, a simple yet effective technique to isolate bugs. This technique automatically removes or chips away parts of a program so that the part that contributes to some symptomatic output becomes more apparent to the user. Program chipping is similar in spirit to traditional program slicing and debugging techniques, but chipping uses very simple techniques based on the syntactic structure of the program. We have developed a chipping tool for Java programs, called ChipperJ, and have run it on a variety of small to large programs, including a Java compiler, looking for various symptoms. The results are promising. The reduced program is generally about 20-35% of the size of the original. ChipperJ takes less than an hour on large programs to perform this reduction; even if it took overnight, that would be reasonable if it saves the developer time. Copyright © 2006 John Wiley & Sons, Ltd.
Phase engineering of controlled entangled number states in a single component Bose–Einstein condensate in a double well

We propose a model for the creation of entangled number states (Schrodinger cat states) of a Bose–Einstein condensate in a double well through simple phase engineering. We show that a π-phase imprinted condensate in a double well evolves, with a simultaneous change of barrier height, to number states with well defined and controlled entanglement. The cat state generation is understood in terms of the underlying classical phase space dynamics of a π-phase displaced coherent state put at the hyperbolic fixed point of the separatrix of a physical pendulum. The extremity and sharpness of the final cat state is determined by the initial barrier height and the rate at which it is ramped during the evolution.
An Arakelov theoretic proof of the equality of conductor and discriminant

Nous donnons une preuve utilisant la theorie d'Arakelov de l'egalite du conducteur et du discriminant.
Conceptual framework of market enforcement of environmental regulations: significance and obstacles to the role of markets in policy design

This article proposes a specific formulation of the concept of market enforcement. It argues that suffering heavy financial losses in the public markets alone does not constitute effective enforcement if such losses are less than the social costs of associated violations. If the social costs of violations are greater than the private losses to shareholders, then this constitutes an implicit transfer of wealth from the public to stakeholders of the polluting entity. The importance of this formulation is that many policy programs are in part predicated on the assumption of the existence of market enforcement. There are social costs if this premise is faulty. The approach to formulating market enforcement of environmental regulations in this article provides background to a possible development of the theory on optimal market penalties for violations of environmental regulations in the same vein as theories of optimal penalties in law.
X-RAY Periodicity in AGN

Significant (marginal) detections of periodic signals have been recently reported in 3 (4) Active Galactic Nuclei. Three of the detections were obtained from long EUVE light curves of moderate-luminosity Seyfert galaxies; the fourth was discovered in Chandra data from the low-luminosity Seyfert 1 galaxy NGC 4395. When compared with Cyg X-1, I find that the period is related to the luminosity as P ∝ L 2/3 rather than the expected one-to-one relationship. This result might be explained if the QPO is associated with the inner edge of the optically thick accretion disk, and the inner-edge radius depends on the source luminosity (or black hole mass).Adiscussion of uncertainties in the period detection methodology is also discussed.
Adaptive beamforming in interference networks via bi-directional training

We study distributed algorithms for adjusting beamforming vectors and receiver filters in multiple-input multiple-output (MIMO) interference networks, with the assumption that each user uses a single beam and a linear filter at the receiver. In such a setting there have been several distributed algorithms studied for maximizing the sum-rate or sum-utility assuming perfect channel state information (CSI) at the transmitters and receivers. The focus of this paper is to study adaptive algorithms for time-varying channels, without assuming any CSI at the transmitters or receivers. Specifically, we consider an adaptive version of the recent Max-SINR algorithm for a time-division duplex system. This algorithm uses a period of bi-directional training followed by a block of data transmission. Training in the forward direction is sent using the current beam-formers and used to adapt the receive filters. Training in the reverse direction is sent using the current receive filters as beams and used to adapt the transmit beamformers. The adaptation of both receive filters and beamformers is done using a least-squares objective for the current block. In order to improve the performance when the training data is limited, we also consider using exponentially weighted data from previous blocks. Numerical results are presented that compare the performance of the algorithms in different settings.
Law of the estimated fact

The pitfalls of making credible estimates as an expert are that the estimate may be propagated as fact, and it may come back as a requirement to be met. However, the original estimator may become untraceable through multiple levels of transmission, and multiple estimates may contain self-cancelling errors. To avoid receiving such `facts', question your sources.
Returns to Education in India

Summary In India both men and women with more education live in households with greater consumption per capita. Yet aggregating across age cohorts and states, an extra year of education brings male cohorts only 4% more consumption and provides no additional consumption for female cohorts. This result is robust to: (1) accounting for survey measurement error, (2) different measures of household consumption and composition, (3) allowing returns to differ by state and school quality, and (4) age misreporting. The only area with substantial returns is entering into regular wage work which still employs only a small fraction of the population.
Differences in education and earnings across ethnic groups in Guatemala

Abstract Most of the research on ethnicity in Central America looks at two groups: indigenous and nonindigenous populations. While indigenous people are disadvantaged relative to the nonindigenous group, the many groups that make up the indigenous population are often times not very similar in terms of personal and group characteristics. But the differences within these groups are important for public policy. Ethnic groups' experience depends on many factors besides education and skill levels. These additional factors may include what has come to be known as “ethnic capital.” That is, the socioeconomic performance of today's workers depends not only on parental skills, but also on the average skills of the ethnic group in the parent's generation. In the United States, when data on ethnic groups is broken down, the black-white comparison may be too simple a characterization. It is argued here that the indigenous-nonindigenous comparison in Guatemala is too simple. Guatemala's household survey, which utilizes two questions to determine an individual's ethnicity (self-perception and language), is used here to examine the question of ethnicity in terms of schooling attainment, earnings and the returns to schooling. The following hypothesis is tested: do higher levels of schooling correspond to higher returns to schooling? Dividing the indigenous sample into the main ethnic groups produces widely different and dramatic results in terms of schooling, earnings and the returns to schooling. Higher levels of schooling correspond to higher returns to schooling by ethnic group. Thus there may be a need to target interventions appropriately to the specific ethnic group in question.
Decomposing the Variation in Generic Advertising Response over Time

A time-varying parameter model of fluid milk and cheese demand reveals that changes in age composition, race composition, and food spending patterns away from home were most important to changes in generic advertising response over time. Advertising response elasticities indicate that generic advertising could be enhanced by targeting young children households for fluid milk, and Asian/Hispanic households for cheese. Results also indicate that shifting targeted advertising efforts to the away-from-home market may increase generic cheese advertising response.
CF2 surface reactivity during hot filament and plasma-enhanced chemical vapor deposition of fluorocarbon films

Abstract Relative gas-phase CF 2 densities and CF 2 surface reactivity were characterized during hot filament chemical vapor deposition (HF-CVD) of fluorocarbon (FC) films using our LIF-based imaging of radicals interacting with surfaces technique. CF 2 density shows a clear dependence on the hexafluoropropylene oxide (HFPO) pressure and filament temperature. CF 2 exhibits a low surface reactivity during deposition of CF 2 -rich FC films. Results are compared to measurements made during plasma-enhanced CVD (PECVD) of FC films. Mass spectrometry measurements reveal energetic ions with mean energies of 29–92 eV are produced in the PECVD source; these energetic ions account for the observed differences in scattering.
Ordered and disordered defect chaos

Abstract Defect chaos is studied numerically in coupled Ginzburg–Landau equations for parametrically driven waves. The motion of the defects is traced in detail yielding their lifetimes, annihilation partners, and distances traveled. In a regime in which in the one-dimensional case the chaotic dynamics is due to double phase slips, the two-dimensional system exhibits a strongly ordered stripe pattern. When the parity-breaking instability to traveling waves is approached this order vanishes and the correlation function decays rapidly. In the ordered regime the defects have a typical lifetime, whereas in the disordered regime the lifetime distribution is exponential. The probability of large defect loops is substantially larger in the disordered regime.
Adaptive control of flexible-joint manipulators

Under the assumption of weak joint elasticity, a singular perturbation argument is used to show that recent adaptive control results for rigid robots can be used to control flexible-joint robots provided a simple correction term is added to the control law to damp out the elastic oscillations at the joints. In this way, fundamental properties of rigid robot dynamics can be exploited to design adaptive control laws for flexible-joint robots that are robust to parametric uncertainty. Experimental results are given to illustrate the theory. >
A ray-tracing study of inclined double-crystal monochromators

Abstract Third-generation synchrotron X-ray sources such as the Advanced Photon Source under construction at Argonne National Laboratory will place severe heat load demands on the first beamline optical element. A cooled, inclined double-crystal monochromator is one of the instruments being developed at the APS to handle these high heat loads while retaining the brilliance of the source. Using a modified version of the 1989 VAX/VMS SHADOW code, we examine the properties of the exit beam for two inclined double-crystal monochromator geometries.
Measured crustal deformation in Imperial Valley, California

Abstract Precise geodetic surveys since 1972 indicate that significant vertical deformation of the land surface continues in Imperial Valley, California. Measured vertical changes as great as 3–5 cm per year indicate that two types of tectonic movement are occurring: (1) a downward regional tilt of the valley surface from the Mexican border northward toward Salton Sea, and (2) a deepening of the structural trough presently occupied by Salton Sea. A comparison of 1972ndash;1977 change contours with 1927 topographic contours shows gross parallelism, suggesting that the recent deformation is a continuation of the tectonism that formed the Salton trough. Ground movement since 1972 has tended to steepen slightly the gradients of streams, canals, and drains on the valley floor and to increase the capacity of Salton Sea. A usable record of eight years of background measurements of tectonic change are available prior to the impact of geothermal production in Imperial Valley.
Ultrasensitive detection of radioactive cesium isotopes using a magneto-optical trap.

We report the first magneto-optical trapping of mdioactive {sup 135}Cs and {sup 137}Cs and a promising means for detecting these isotopes to ullrasensilive lcvels by a system coupling the magneto-optical trap (MOT) to a mass separator. The mass separator efficiently delivers a 20 kV ion beam of either isotope into a quartzcube MOT cell having in one corner a small-diameter Zr foil, on which the ion beam is focused and into which the ions are implantetl. Inductive heating of thc foil releases {approx}45% of the implanted atoms into a MOT that uses large diameter beams and a dry-film coating to capture 3% of the released vapor. MOT fluorescence signals were found to increasc linearly with the number of foil-implanted atoms over a range of 10{sup 4} to 10{sup 7} in trapped-atom number. The measured slope of MOT signal versus number implanted was equal in the case each isotope to within 4%, signifying our ability to measure {sup 137}Cs/{sup 135}Cs ratios to within 4%. The isotopic selectivities of the mass separator and MOT combine to suppress interfering signal from {sup 133}Cs by a factor of greater than 5 x 10{sup 12} in the case of detecting {sup 135}Cs or {sup 137}Cs.more » Our present sample detection sensitivity is one million atoms.« less
Orientation Dependent Binding Energy of Graphene on Pd(111)

Graphene, a two-dimensional crystalline sheet of carbon, has generated considerable attention owing to its ultra-thin geometry, high carrier mobility and tunable band gap, with potential applications in high-performance, low-power electronics and as transparent electrodes. Since graphene–based devices require metal (or metallic) contacts, knowledge of the structural and electronic properties of the metal-graphene interfaces is essential. Previous theoretical studies of graphene-metal contacts indicate that their electronic properties depend on the metal-graphene binding energies. For example, strongly interacting metals can induce a charge transfer from or to graphene, resulting in p- or n-type doping. Here, using Pd(111) as a example substrate, we focus on understanding the influence of the orientation of graphene on its binding to the substrate.Copyright © 2011 by ASME
Hecke eigenforms as products of eigenforms

Abstract We investigate when the product of two Hecke eigenforms for Γ 1 ( N ) is again an eigenform. In this paper we prove that among all levels N , the product of two eigenforms for Γ 1 ( N ) of weight 2 or greater is an eigenform only 61 times, and give a complete list. Duke and Ghate independently addressed this topic for eigenforms at level 1, proving there are only 16 such identities. Ghate subsequently proved related results for almost everywhere eigenforms of weight 3 or greater for Γ 1 ( N ) , with N squarefree. Our work extends the results of Ghate to eigenforms of weight 2 or greater, with no restrictions on the level. The methods we use are elementary and effective, and make no use of the Rankin–Selberg convolution.
Global U(1) R-symmetry and conformal invariance of (0,2) models

Abstract We derive a condition under which (0,2) linear sigma models possess a “left-moving” conformal stress tensor in Q + cohomology (i.e. which leaves invariant the “right-moving” ground states) even away from their critical points. At the classical level this enforces quasihomogeneity of the superpotential terms. The persistence of this structure at the quantum level on the worldsheet is obstructed by an anomaly unless the charges and superpotential degrees satisfy a condition which is equivalent to the condition for the cancellation of the anomaly in a particular “right-moving” U(1) R-symmetry.
Birth, death and public good provision

We explore the effect of fixed versus dynamic group membership on public good provision. In a novel experimental design, we modify the traditional voluntary contribution mechanism (VCM) by periodically replacing old members of a group with new members over time. Under this dynamic, overlapping generations matching protocol we find that average contributions experience significantly less decay over time relative to a traditional VCM environment with fixed group membership and a common termination date. These findings suggest that the traditional pattern of contribution and decay seen in many public goods experiments may not accurately reflect behavior in groups with changing membership, as is the case in many real-world environments.
Inductive Classifying Artificial Network for Vehicle Type Categorization

As transportation surveillance technology continues to advance, the measurement of more complete traffic information is becoming increasingly feasible. ICAN stands for Inductive Classifying Artificial Network and is used to conveniently describe a self–organizing feature map (SOFM) for vehicle type categorization using inductive signatures as input. Vehicle type categorization is the separation of vehicles into predefined classes and can be useful for improving transportation efficiency, cost, environmental sustainability, enforcement, safety, and education. ICAN mainly focuses on the challenging task of differentiating between two–axle vehicles such as passenger car, sports utility vehicle (SUV), van, truck, and bus. This is in contrast to systems that classify according to the number of axles. One characteristic of ICAN is the simplicity of the 13–neuron one–dimensional neural network, and the employment of a small training set of 13 signatures. The overall classification results of 87% (data set 1) and 82% (data set 2) for seven categories coupled with consistent performance across all vehicle categories was significant and encouraging. Field freeway data was used for testing ICAN; representative signatures and video images of different vehicle types are presented.
Geodesics on weighted projective spaces

We study the inverse spectral problem for weighted projective spaces using wave-trace methods. We show that in many cases one can “hear” the weights of a weighted projective space.
Serum Lipoprotein and Cholesterol Concentrations Comparison of Rural Costa Rican, Guatemalan, and United States Populations

A previous study indicated that Guatemalan Indians, both male and female, tended to maintain low levels of serum cholesterol throughout adulthood but that beta-lipoprotein fractions increased with age, as is usually the case in populations in the United States. To investigate whether race was of importance in this unexpected dissociation between these lipid fractions, a similar study was done with a rural group in Costa Rica, which was comparable in the diet consumed and in many other environmental factors, but of pure European origin. At all ages the cholesterol values were slightly higher but the same type of dissociation was observed.
Influence of tesseral harmonics on nearly circular polar and equatorial orbits

1 Bahar, L. Y., "An application of Macaulay's brackets in the integration of some discontinuous expressions arising in beam theory," J. Aerospace Sci. 29, 605 (1962). 2 Urry, S. A., "The use of Macaulay's brackets in the analysis of laterally loaded struts and tie-bars," AIAA J. 1, 462-463 (1963). 3 Macaulay, W. H., "A note on the deflection of beams," Messenger Math. 48, 129 (1919). 4 Seide, P., "Review 5704," Appl. Mech. Rev. 16, 783 (1963). 5 Weissenburger, J. T., "Integration of discontinuous expressions arising in beam theory," AIAA J. 2, 106-108 (1964). 6 Clebsch, A., Theorie Der Elasticity Fester Korper (B. G. Teubner, Leipzig, Germany, 1862), Vol. 87, p. 462. 7 Case, J., Strength of Materials (Edward Arnold and Co., London, 1932), 2nd ed. 8 Piaggio, H. T. H., Differential Equations (G. Bell and Sons, London, 1942), Chap. VII, p. 88. 9 Hicks, R., "Symmetrically loaded circular plates under the combined action of lateral and end loading," Aeronaut. Quart. 10,266-282(1959).
Simulating blocks in treatment planning calculations

It is difficult to make an accurate calculation of dose distribution incorporating blocks using a ray model. One approach is to simulate the blocking in a treatment planning distribution by using negatively weighted beams. A second is to employ an external contour. The parameters of the negative beam or contour can be adjusted using empirical dosimetric data. This paper discusses the calculation of the dose distributions using negatively weighted beams and external contours, compares them with measurements in and around blocked areas for a range of field sizes, block sizes, and depths of interest in treatment planning applications, for 60Co, 6 MV, and 10 MV beams, and assesses their applicability.
Computer technology as object language: Revisiting office design

Object language is a term that describes the messages that objects convey to people. This paper extends previous research on the object language associated with office design elements such as the placement of one's desk and office messiness by examining the role of computer technology as an additional form of object language. Computer technology was operationalized in Study 1 in terms of the innovativeness of technology displayed in an office, while Study 2 focused on the portability of computer technology. Undergraduate students responded to photographs of faculty offices exhibiting various combinations of office messiness, desk placement and technology. Results showed that while computer technology plays a more subtle role in visitor attributions about the officeholder in comparison to office messiness or desk placement, computer technology does convey messages about work performance, especially time management skills. The main role played by computer technology is in terms of its interaction with office messiness. Results of the role of office design in impression management are discussed.
Cesium effect: high chemoselectivity in direct N-alkylation of amines

A novel method for the mono-N-alkylation of primary amines, diamines, and polyamines was developed using cesium bases in order to prepare secondary amines efficiently. A cesium base not only promoted alkylation of primary amines but also suppressed overalkylations of the produced secondary amines. Various amines, alkyl bromides, and alkyl sulfonates were examined, and the results demonstrated this methodology was highly chemoselective to favor mono-N-alkylation over dialkylation. In particular, use of either sterically demanding substrates or amino acid derivatives afforded the secondary amines exclusively, offering wide applications in peptidomimetic syntheses.
Error Performance of Channel Coding in Random-Access Communication

A new channel coding approach was proposed by Luo and Ephremides for random multiple-access communication over the discrete-time memoryless channel. The coding approach allows users to choose their communication rates independently without sharing the rate information among each other or with the receiver. The receiver will either decode the messages or report a collision depending on whether reliable message recovery is possible. It was shown that, asymptotically as the codeword length goes to infinity, the set of communication rates supporting reliable message recovery can be characterized by an achievable region which equals Shannon's information rate region without a convex hull operation. In this paper, we derive achievable bounds on error probabilities, including the decoding error probability and the collision miss detection probability, of random multiple-access systems with a finite codeword length. Achievable error exponents are obtained by taking the codeword length to infinity.
Parallel Combinatorial Synthesis of Glycodendrimers and Their Hydrogelation Properties

A series of glycodendrons has been assembled using a parallel combinatorial approach, and it has been shown that subtle structural variations between dendrons give rise to significant differences in their hydrogelation behavior.
High Energy Laser Beam Scattering By Atmospheric Aerosol Aureoles

The interaction of high energy laser beams with aerosols in the atmosphere produces non-uniform temperature variations in the medium surrounding the aerosols. These non-uniformities in the ambient index of refraction act as scattering centers for the laser beam. The basic thermodynamics and conservation equations are solved numerically for pulsed high energy lasers interacting with aerosol water droplet systems. The resulting temperature variations at the surface of the aerosol and in the surrounding medium are found for a variety of input variables including absorbed laser intensity, pulse repetition rate, pulse time, and particle radius. The laser beam scattering is calculated through the Born approximation utilizing the computed temperatures. The range of variables for which laser beam scattering by aerosol aureole systems may be important is discussed.
Chiral 3-(hydroxymethyl)oxiranecarboxylic acids via the Jocic reaction

Abstract (R,R)-2,2-Dimethyl-α-(trichloromethyl)-1,3-dioxolane-4-methanol 5 and its (R,S)-isomer 6 were converted into the TBDMS ethers of (2S,3R)-methyl 3-(hydroxymethyl)oxiranecarboxylate 12 and its (2R,3R)-isomer 14, respectively, with 100% stereoselectivity. threo-Glycols afforded cis-epoxides, while erythro-glycols provided the trans-isomers.
On the distribution of Sidon series

Suppose that G is a compact abelian group with dual group F. Denote the normalized Haar measure on G by #. Let C(G) be the Banach space of continuous complex-valued functions on G. If S CF, a function f E L l ( G ) is called S-spectral whenever f is supported in S, where here and throughout the paper A denotes taking the Fourier transform. The collection of S-spectral functions that belong to a class of functions ]/Y will be denoted by l/Vs.
Synthesis of Vancomycin from the Aglycon

Vancomycin-resistant bacterial strains pose a serious threat to human health. Efforts to overcome vancomycin resistance by modifying the natural product have shown that the carbohydrates help modulate biological activity. To explore the mechanisms by which the carbohydrates function, it would be useful to have access to vancomycin derivatives containing different disaccharides. We now describe the synthesis of vancomycin from a readily available protected aglycon. This chemistry lays the groundwork for wide-ranging investigations of the roles of the carbohydrates in the biological activity of vancomycin. Moreover, in developing methods to glycosylate vancomcyin, we have extended the utility of the sulfoxide glycosylation reaction considerably by making it possible to use unhindered esters as neighboring groups. The chemistry we describe may also have implications for how to improve some other glycosylation methods.
Model Simulations of a Shock-Cloud Interaction in the Cygnus Loop

We present optical observations and two-dimensional hydrodynamic modeling of an isolated shocked ISM cloud. Hα images taken in 1992.6 and 2003.7 of a small optical emission cloud along the southwestern limb of the Cygnus Loop were used to measure positional displacements of ~01 yr-1 for surrounding Balmer-dominated emission filaments and 0025-0055 yr-1 for internal cloud emission features. These measurements imply transverse velocities of 250 and 80-140 km s-1 for ambient ISM and internal cloud shocks, respectively. A lack of observed turbulent gas stripping at the cloud-ISM boundary in the Hα images suggests that there is not an abrupt density change at the cloud-ISM boundary. Also, the complex shock structure visible within the cloud indicates that the cloud's internal density distribution is two-phased—a smoothly varying background density that is populated by higher density clumps. Guided by the Hα images, we present model results for a shock interacting with a nonuniform ISM cloud. We find that this cloud can be well modeled by a smoothly varying power-law core with a density contrast of ~4 times the ambient density, surrounded by a low-density envelope with a Lorentzian profile. The lack of sharp density gradients in such a model inhibits the growth of Kelvin-Helmholtz instabilities, consistent with the cloud's appearance. Our model results also suggest that cloud clumps have densities ~10 times the ambient ISM density and account for ~30% of the total cloud volume. Moreover, the observed spacing of internal cloud shocks and model simulations indicate that the distance between clumps is ~4 clump radii. We conclude that this diffuse ISM cloud is best modeled by a smoothly varying, low-density distribution coupled to higher density, moderately spaced internal clumps.
On a theorem of Kontsevich

In [12] and [13], M. Kontsevich introduced graph homology as a tool to compute the homology of three infinite dimensional Lie algebras, associated to the three operads "commutative," "associative" and "Lie." We generalizehis theorem to all cyclic operads, in the process giving a more careful treatment of the construction than in Kontsevich's original papers. We also give a more explicit treatment of the isomorphisms of graph homologies with the homology of moduli space and Out(F r ) outlined by Kontsevich. In [4] we defined a Lie bracket and cobracket on the commutative graph complex, which was extended in [3] to the case of all cyclic operads. These operations form a Lie bi-algebra on a natural subcomplex. We show that in the associative and Lie cases the subcomplex on which the bi-algebra structure exists carries all of the homology, and we explain why the subcomplex in the commutative case does not.
Phase Variation in the Pulse Profile of SMC X-1

We present the results of the timing and spectral analysis of X-ray high-state observations of the high-mass X-ray pulsar SMC X-1 with Chandra, XMM-Newton, and ROSAT, taken between 1991 and 2001. The source has LX ~ × 1038 ergs s-1, and the spectra can be modeled as a power law plus blackbody with kTBB ~ 0.18 and a reprocessed emission radius RBB ~ 2 × 108 cm, assuming a distance of 60 kpc to the source. Energy-resolved pulse profiles show several distinct forms, more than half of which include a second pulse in the soft profile, previously documented only in hard energies. We also detect significant variation in the phase shift between hard and soft pulses, as has recently been reported in Her X-1. We suggest an explanation for the observed characteristics of the soft pulses in terms of precession of the accretion disk.
An Implicit Factored Scheme for the Compressible Navier-Stokes Equations

An implicit finite-difference scheme is developed for the numerical solution of the compressible Navier-Stokes equations in conservation- law form. The algorithm is second-order- time accurate, noniterative, and spatially factored. In order to obtain an efficient factored algorithm, the spatial cross derivatives are evaluated explicitly. However, the algorithm is unconditional ly stable and, although a three-time-lev el scheme, requires only two time levels of data storage. The algorithm is constructed in a "delta" form (i.e., increments of the conserved variables and fluxes) that provides a direct derivation of the scheme and leads to an efficient computational algorithm. In addition, the delta form has the advantageous property of a steady state (if one exists) independent of the size of the time step. Numerical results are presented for a two-dimensiona l shock boundary-layer interaction problem.
A viable model of dynamical supersymmetry breaking in the hidden sector

Abstract We propose a simple and natural model of dynamical supersymmetry breaking, which could be used as a mechanism for spontaneous supersymmetry breaking in a gravitationally coupled hidden sector. The gaugino masses in the visible sector are naturally of the same size as the squark, slepton, and gravitino masses.
Lattice quantization error for redundant representations

Redundant systems such as frames are often used to represent a signal for error correction, denoising and general robustness. In the digital domain quantization needs to be performed. Given the redundancy, the distribution of quantization errors can be rather complex. In this paper we study quantization error for a signal X in ℝ d represented by a frame using a lattice quantizer. We characterize the asymptotic distribution of the quantization error as the cell size of the lattice goes to zero. We apply these results to get the necessary and sufficient conditions for the White Noise Hypothesis to hold asymptotically in the case of the pulse-code modulation scheme. This is an abbreviated version of a paper that will appear elsewhere in a regular refereed journal. The full version of the paper also contains results in the more general settings.
N-Heterocyclic carbene-catalyzed enantioselective annulations: a dual activation strategy for a formal [4+2] addition for dihydrocoumarins

A highly efficient asymmetric formal [4+2] annulation for the synthesis of dihydrocoumarins has been developed via an in situ activated NHC catalysis. Both electrophilic and nucleophilic species are generated in situ simultaneously whereby acyl imidazoles facilitated rapid formation of an NHC-enolate intermediate to afford the [4+2] dihydrocoumarin adducts.