cssi/SciSciGPT-SciSciNet huggingface dataset:
Effective dielectric tensor for electromagnetic wave propagation in random media

We derive exact strong-contrast expansions for the effective dielectric tensor ee of electromagnetic waves propagating in a two-phase composite random medium with isotropic components explicitly in terms of certain integrals over the n-point correlation functions of the medium. Our focus is the long-wavelength regime, i.e., when the wavelength is much larger than the scale of inhomogeneities in the medium. Lower-order truncations of these expansions lead to approximations for the effective dielectric constant that depend upon whether the medium is below or above the percolation threshold. In particular, we apply two- and three-point approximations for ee to a variety of different three-dimensional model microstructures, including dispersions of hard spheres, hard oriented spheroids, and fully penetrable spheres as well as Debye random media, the random checkerboard, and power-law-correlated materials. We demonstrate the importance of employing n-point correlation functions of order higher than two for hig...
OXIDATION OF CERTAIN 4-SUBSTITUTED PHENETHYL ALCOHOLS WITH COLLINS REAGENT: ON THE MECHANISM OF A CARBON-CARBON BOND CLEAVAGE

Abstract A mechanism is proposed for a carbon-carbon bond cleavage observed in the oxidation of certain 4-substituted phenethyl alcohols with Collins reagent.
Clinical Assessment and Management Examination—Outpatient (CAMEO): Its Validity and Use in a Surgical Milestones Paradigm

OBJECTIVES: Clinical Assessment and Management Examination—Outpatient (CAMEO) is a metric for evaluating the clinical performance of surgery residents. The aim of this study was to investigate the measurement characteristics of CAMEO and propose how it might be used as an evaluation tool within the general surgery milestones project. DESIGN: A total of 117 CAMEO evaluations were gathered and used for analysis. Internal consistency reliability was estimated, and item characteristics were explored. A Kruskal-Wallis procedure was performed to discern how well the instrument discriminated between training levels. An exploratory factor analysis was also conducted to understand the dimensionality of the evaluation.
Cosmological Production of Baryons

Departures from thermal equilibrium which are likely to occur in an expanding universe allow the production of an appreciable net baryon density by processes which violate baryon-number conservation. It is shown that the resulting baryon to entropy ratio can be calculated in terms of purely microscopic quantities.
Relo: Helping Users Manage Context during Interactive Exploratory Visualization of Large Codebases

As software systems grow in size and use more third-party libraries and frameworks, the need for developers to understand unfamiliar large codebases is rapidly increasing. In this paper, we present a tool, Relo, that supports developers understanding by allowing interactive exploration of code. As the developer explores relationships found in the code, Relo builds and automatically manages the context in a visualization, thereby helping build the developers mental representation of the code. Developers can group viewed artifacts or use the viewed items to ask Relo for further exploration suggestions, with Relo providing features to limit the growth of the diagram. To ensure developers dont get overwhelmed, Relo has been built with a user-centered approach, and preliminary evaluations with developers exploring new code have shown them to find the tool intuitive and helpful.
Measurement of Flow Phenomena in a Lower Plenum Model of a Prismatic Gas-Cooled Reactor

Mean-velocity-field and turbulence data are presented that measure turbulent flow phenomena in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor (GCR) similar to a General Atomics Gas-Turbine-Modular Helium Reactor (GTMHR) design. The data were obtained in the Matched-Index-of-Refraction (MIR) facility at Idaho National Laboratory (INL) and are offered for assessing computational fluid dynamics (CFD) software. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. This paper reviews the experimental apparatus and procedures, presents a sample of the data set, and reviews the INL Standard Problem. Results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). The flow in the lower plenum consists of multiple jets injected into a confined cross flow - with obstructions. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to approximate flow scaled to that expected from the staggered parallel rows of posts in the reactor design. The model is fabricated from clear, fused quartz to match the refractive-index of the mineral oil working fluid so that optical more » techniques may be employed for the measurements. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages in and around objects to be obtained without locating intrusive transducers that will disturb the flow field and without distortion of the optical paths. An advantage of the INL system is its large size, leading to improved spatial and temporal resolution compared to similar facilities at smaller scales. A three-dimensional (3-D) Particle Image Velocimetry (PIV) system was used to collect the data. Inlet jet Reynolds numbers (based on the jet diameter and the time-mean average flow rate) are approximately 4,300 and 12,400. Uncertainty analysis and a discussion of the standard problem are included. The measurements reveal undeveloped, non-uniform, turbulent flow in the inlet jets and complicated flow patterns in the model lower plenum. Data include three-dimensional vector plots, data displays along the coordinate planes (slices) and presentations that describe the component flows at specific regions in the model. Information on inlet conditions are also presented. « less
Obtaining Spectra of Turbulent Velocity from Observations

We discuss a long-standing problem of how turbulence can be studied using observations of Doppler broadened emission and absorption lines. The focus of the present review is on two new techniques, the Velocity–Channel Analysis (VCA), which makes use of the channel maps, and the Velocity Coordinate Spectrum (VCS), which utilizes the fluctuations measured along the velocity axis of the Position–Position Velocity (PPV) data cubes. Both techniques have solid theoretical foundations based on analytical calculations as well as on numerical testings. Among the two the VCS, which has been developed quite recently, has two unique features. First of all, it is applicable to turbulent volumes that are not spatially resolved. Second, it can be used with absorption lines that do not provide good spatial sampling of different lags over the image of the turbulent object. In fact, recent studies show that measurements of absorption line along less than 10 absorption directions are sufficient for a reliable recovering of the underlying spectrum of the turbulence. Moreover, both weak absorption lines and absorption lines in saturated regime can be used, which extends the applicability of the technique. Our comparison of the VCA and the VCS with a more traditional technique of Velocity Centroids shows that the former two techniques recover reliably the spectra of supersonic turbulence, while the Velocity Centroids may be used only for studying subsonic turbulence. We discuss spectra of astrophysical turbulence obtained with the VCA and the VCS techniques.
The complexity of the core model

If there is no inner model with a cardinal κ such that ο(κ) = κ ++ then the set K ∩ H ω 1 is definable over H ω 1 by a Δ 4 formula, and the set of countable initial segments of the core model is definable over H ω 1 by a Π 3 formula. We show that if there is an inner model with infinitely many measurable cardinals then there is a model in which is not definable Σ 3 by any Σ 3 formula, and K ∩ H ω 1 is not definable by any boolean combination of Σ 3 formulas.
Adaptive solutions to the mutual exclusion problem

Algorithms for mutual exclusion that adapt to the current degree of contention are developed. A filter and a leader election algorithm form the basic building blocks. The algorithms achieve system response times that are independent of the total number of processes and governed instead by the current degree of contention. The final algorithm achieves a constant amortized system response time.
Ad hoc on-demand multipath distance vector routing

We develop an on-demand, multipath distance vector routing protocol for mobile ad hoc networks. Specifically, we propose multipath extensions to a well-studied single path routing protocol known as ad hoc on-demand distance vector (AODV). The resulting protocol is referred to as ad hoc on-demand multipath distance vector (AOMDV). The protocol guarantees loop freedom and disjointness of alternate paths. Performance comparison of AOMDV with AODV using ns-2 simulations shows that AOMDV is able to effectively cope with mobility-induced route failures. In particular, it reduces the packet loss by up to 40% and achieves a remarkable improvement in the end-to-end delay (often more than a factor of two). AOMDV also reduces routing overhead by about 30% by reducing the frequency of route discovery operations. Copyright © 2006 John Wiley & Sons, Ltd.
Theory of depletion-induced phase transition from chiral smectic-A twisted ribbons to semi-infinite flat membranes

We consider a theoretical model for the chiral smectic A twisted ribbons observed in assemblies of fd viruses condensed by depletion forces. The depletion interaction is modeled by an edge energy assumed to be proportional to the depletant polymer in solution. Our model is based on the Helfrich energy for surface bending and the de Gennes model of chiral smectic A liquid crystals with twist penetration at the edge. We consider two variants of this model, one with the conventional Helfrich Gaussian curvature term, and a second with saddle-splay energy. A mean field analysis of both models yields a first-order phase transition between ribbons and semi-infinite flat membranes as the edge energy is varied. The phase transition line and tilt angle profile are found to be nearly identical for the two models; the pitch of the ribbon, however, does show some differences. Our model yields good qualitative agreement with experimental observations if the sign of the Gaussian curvature or saddle-splay modulus is chosen to favor negative Gaussian curvature.
Hydrodynamic Suppression of Soot Emissions in Laminar Diffusion Flames

Effects of flow (hydrodynamic) properties on soot formation and oxidation in nonpremixed hydrocarbon/air flames were studied, emphasizing conditions where effects of buoyancy are small in coflowing laminar jet diffusion flames. Effects of air/fuel-stream velocity ratios were of particular interest; therefore, the experiments were carried out at reduced pressures (0.19-0.50 atm) in order to minimize effects of flow acceleration due to buoyancy. Test conditions included acetylene, propylene, and 1,3-butadiene flames burning in air with air/fuel-stream velocity ratios in the range 0.4-6.7. Measurements included laminar smoke-point properties, as well as the following flame structure properties: soot volume fractions, temperatures, soot structure, concentrations of major gas species, and velocities. The measurements showed that laminar smoke-point flame lengths can be increased, and soot emissions possibly suppressed entirely, by increasing air/fuel-stream velocity ratios. The flame structure measurements suggest that the mechanism of this effect involves the magnitude and direction of flow velocities relative to the flame sheet. In particular, large air/fuel-stream velocity ratios cause soot to form in cool and fuel-rich gases, inhibiting soot nucleation, and then to be drawn directly toward the flame sheet with a limited residence time, inhibiting soot growth, so that capabilities to complete the oxidation of soot are enhanced and the tendencies to emit soot are reduced.
Enantioselective synthesis of SNAP-7941: chiral dihydropyrimidone inhibitor of MCH1-R.

An enantioselective synthesis of SNAP-7941, a potent melanin concentrating hormone receptor antagonist, was achieved by using two organocatalytic methods. The first method utilized to synthesize the enantioenriched dihydropyrimidone core was the Cinchona alkaloid-catalyzed Mannich reaction of β-keto esters to acylimines and the second was the chiral phosphoric acid-catalyzed Biginelli reaction. Completion of the synthesis was accomplished via selective urea formation at the N3 position of the dihydropyrimidone with the 3-(4-phenylpiperidin-1-yl)propylamine side chain fragment. The synthesis of SNAP-7921 highlights the utility of asymmetric organocatalytic methods in the construction of an important class of chiral heterocycles.
Optimal Compliant Flapping Mechanism Topologies With Multiple Load Cases

The conceptual design of effective actuation mechanisms for flapping wing micro air vehicles presents considerable challenges, with competing weight, power, authority, and life cycle requirements. This work utilizes topology optimization to obtain compliant flapping mechanisms; this is a well-known tool, but the method is rarely extended to incorporate unsteady nonlinear aeroelastic physics, which must be accounted for in the design of flapping wing vehicles. Compliant mechanism topologies are specifically desired to perform two tasks: (1) propulsive thrust generation (symmetric motions of a left and a right wing) and (2) lateral roll moment generation (asymmetric motions). From an optimization standpoint, these two tasks are considered multiple load cases, implemented by scheduling the actuation applied to the mechanism’s design domain. Mechanism topologies obtained with various actuation-scheduling assumptions are provided, along with the resulting flapping wing motions and aerodynamic force/moment generation. Furthermore, it is demonstrated that both load cases may be used simultaneously for future vehicle control studies: gradual transition from forward flight into a turning maneuver, for example.
Search for a realistic Kaluza-Klein theory

An attempt is made to construct a realistic model of particle physics based on eleven-dimensional supergravity with seven dimensions compactified. It is possible to obtain an SU(3) × SU(2) × U(1) gauge group, but the proper fermion quantum numbers are difficult to achieve.
Superfluid nuclear matter calculations

Abstract We present a method to calculate nuclear matter properties in the superfluid phase. The method is based on the use of self-consistent off-shell nucleon propagators in the T-matrix equation. Such a complete treatment of the spectral function is required below and around T c due to a pseudogap formation in the spectral function. In the superfluid phase we introduce the anomalous self-energy in the fermion propagators and in the T-matrix equation, consistently with the strong coupling BCS equations. The equations for the nucleon spectral function include both a contribution of condensed and scattering pairs. The method is illustrated by numerical calculations. Above T c pseudogap formation is visible in the spectral function and below T c a superfluid gap also appears.
Synchronization of pairwise-coupled, identical, relaxation oscillators based on metal- insulator phase transition devices: A model study

Computing with networks of synchronous oscillators has attracted wide-spread attention as novel materials and device topologies have enabled realization of compact, scalable and low-power coupled oscillatory systems. Of particular interest are compact and low-power relaxation oscillators that have been recently demonstrated using MIT (metal-insulator-transition) devices using properties of correlated oxides. Further the computational capability of pairwise coupled relaxation oscillators has also been shown to outperform traditional Boolean digital logic circuits. This paper presents an analysis of the dynamics and synchronization of a system of two such identical coupled relaxation oscillators implemented with MIT devices. We focus on two implementations of the oscillator: (a) a D-D configuration where complementary MIT devices (D) are connected in series to provide oscillations and (b) a D-R configuration where it is composed of a resistor (R) in series with a voltage-triggered state changing MIT device ...
An empirical method for estimating instream pre-mining pH and dissolved Cu concentration in catchments with acidic drainage and ferricrete

Abstract Methods for assessing natural background water quality of streams affected by historical mining are vigorously debated. An empirical method is proposed in which stream-specific estimation equations are generated from relationships between either pH or dissolved Cu concentration in stream water and the Fe/Cu concentration ratio in Fe-precipitates presently forming in the stream. The equations and Fe/Cu ratios for pre-mining deposits of alluvial ferricrete then were used to reconstruct estimated pre-mining longitudinal profiles for pH and dissolved Cu in three acidic streams in Montana, USA. Primary assumptions underlying the proposed method are that alluvial ferricretes and modern Fe-precipitates share a common origin, that the Cu content of Fe-precipitates remains constant during and after conversion to ferricrete, and that geochemical factors other than pH and dissolved Cu concentration play a lesser role in determining Fe/Cu ratios in Fe-precipitates. The method was evaluated by applying it in a fourth, naturally acidic stream unaffected by mining, where estimated pre-mining pH and Cu concentrations were similar to present-day values, and by demonstrating that inflows, particularly from unmined areas, had consistent effects on both the pre-mining and measured profiles of pH and Cu concentration. Using this method, it was estimated that mining has affected about 480 m of Daisy Creek, 1.8 km of Fisher Creek, and at least 1 km of Swift Gulch. Mean values of pH decreased by about 0.6 pH units to about 3.2 in Daisy Creek and by 1–1.5 pH units to about 3.5 in Fisher Creek. In Swift Gulch, mining appears to have decreased pH from about 5.5 to as low as 3.6. Dissolved Cu concentrations increased due to mining almost 40% in Daisy Creek to a mean of 11.7 mg/L and as much as 230% in Fisher Creek to 0.690 mg/L. Uncertainty in the fate of Cu during the conversion of Fe-precipitates to ferricrete translates to potential errors in pre-mining estimates of as much as 0.25 units for pH and 22% for dissolved Cu concentration. The method warrants further testing in other mined and unmined watersheds. Comparison of pre-mining water-quality estimates derived from the ferricrete and other methods in single watersheds would be particularly valuable. The method has potential for use in monitoring remedial efforts at mine sites with ferricrete deposits. A reasonable remediation objective might be realized when the downstream pattern of Fe/Cu ratios in modern streambed Fe-precipitates corresponds to the pattern in pre-mining alluvial ferricrete deposits along a stream valley.
Synthesis and Characterization of 1,4-Dichlorospiropentadiene

Abstract 1,4-Dichlorospiropentadiene was prepared by vacuum gas-solid elimination of compound 3 over solid (n-Bu) 4 N + F − and characterized by 1 H and 13 C NMR spectroscopy at −103 °C.
Antidepressant-induced suicide, violence and mania: Risks for military personnel

The newer antidepressants frequently cause suicide, violence and manic-like symptoms of activation or over- stimulation, presenting serious hazards to active duty soldiers who carry weapons under stressful conditions. These antidepressant-induced symptoms of activation can mimic Post Traumatic Stress Disorder (PTSD) and are likely to worsen this common disorder in soldiers, increasing the hazard when they are prescribed to military personnel. Antidepressants should not be prescribed to soldiers during or after deployment. Recently concern has been expressed about the increased prescription of psychiatric medications, especially antidepressants, to military personnel (46, 57). In presentations at military conferences on combat stress (8, 10) and in testimony before the U.S. House of Representatives Veterans Affairs Committee (9), I have pointed to a probable causal relationship between increasing rates of antidepressant prescription and increasing rates of suicide in the military. This paper reviews and evaluates the relevant scientific data.
The phylogeny and ontogeny of behavior

Responses are strengthened by consequences having to do with the survival of individuals and species. With respect to the provenance of behavior, we know more about ontogenic than phylogenic contingencies. The contingencies responsible for unlearned behavior acted long ago. This remoteness affects our scientific methods, both experimental and conceptual. Until we have identified he variables responsible for an event, we tend to invent causes. Explanatory entities such as “instincts,” “drives,” and “traits” still survive. Unable to show how organisms can behave effectively under complex circumstances, we endow them with special abilities permitting them to do so.Behavior exhibited by most members of a species is often accepted as inherited if all members were not likely to have been exposed to relevant ontogenic contingencies. When contingencies are not obvious, it is perhaps unwise to call any behavior either inherited or acquired, as the examples of churring in honey guides and following in imprinted ducklings show. Nor can the relative importance of phylogenic and ontogenic contingencies be argued from instances in which unlearned or learned behavior intrudes or dominates. Intrusions occur in both directions.Behavior influenced by its consequences seems directed toward the future, but only past effects are relevant. The mere fact that behavior is adaptive does not indicate whether phylogenic or ontogenic processes have been responsible for it. Examples include the several possible provenances of imitation, aggression, and communication. The generality of such concepts limits their usefulness. A more specific analysis is needed if we are to deal effectively with the two kinds of contingencies and their products.
STORAGE POOL DEFICIENCY IN NEONATAL PLATELETS

It is recognized that newborns exhibit a transient thrombocyropathy. Some investigators have described this as an “aspirin-like” defect, while others have ascribed it to a “storage-pool” abnormality. In an attempt to resolve this discrepancy platelets (plts.) from IP normal newborns, 10 normal adults and 10 aspirin created adults were studied. None of the mothers of the newborn infants had ingested drugs known to interfere with plt. function. Plt. aggregations with ADP (3uM), epinephrine (5uM) and collagen demonstrated abormal 2nd phase aggregation in both the newborns and in the aspirin treated adults. When mixtures of equal volumes of pits, from newborn and aspirin treated controls were tested, normal, irreversible aggregation was observed. Mutual correction was not observed on preincubation of newborn plts, with aspirin prior to mixing. When plt. malonaldehyde production was measured, PS an index of prostaglandin synthesis, in the presence of thrombin, or MEM, no differences were observed between normal adults and newborn plts. Malonaldehyde production was markedly reduced in the aspirin treated controls. Storage-pool deficient plts., when combined with aspirinized plts., prove mutually corrective in aggregation studies since storage pool deficient plts, overcome the abnormality in prostaglandin synthesis of the aspirin treated cells. These latter cells in turn provide the necessary storage-pool nucleotides to cause mutual correction and irreversible aggregation of the mixture. Our findings indicate that newborn pits, have a “storage-pool” defect.
Unified approach for Euler-Lagrange equation arising in calculus of variations

We address the development of a unified approach for the necessary conditions for optimization of a functional arising in calculus of variations. In particular, we develop a unified approach for the Euler–Lagrange equation, that is simultaneously applicable to both shift (q)-operator-based discrete-time systems and the derivative (d/dt)-operator-based continuous-time systems. It is shown that the Euler–Lagrange results that are now obtained separately for continuous- and discrete-time systems can be easily obtained from the unified approach. An illustrative example is given. Copyright © 2005 John Wiley & Sons, Ltd.
Properties of Gamma-Ray Burst Time Profiles Using Pulse Decomposition Analysis

The time profiles of many gamma-ray bursts consist of distinct pulses, which offers the possibility of characterizing the temporal structure of these bursts using a relatively small set of pulse shape parameters. This pulse decomposition analysis has previously been performed on a small sample of bright, long bursts using binned data from BATSE, which comes in several data types, and on a sample of short bursts using the BATSE time-tagged event (TTE) data type. We have developed an interactive pulse-fitting program using the phenomenological pulse model of Norris et al. and a maximum-likelihood fitting routine. We have used this program to analyze the time-to-spill (TTS) data for all bursts observed by BATSE up through trigger number 2000, in all energy channels for which TTS data is available. This represents a total of 211 distinct bursts analyzed in one or more energy channels. We present statistical information on the attributes of pulses comprising these bursts, including relations between pulse characteristics in different energy channels and the evolution of pulse characteristics through the course of a burst. We carry out simulations to determine the biases that our procedures may introduce. We find that pulses tend to have shorter rise times than decay times, and tend to be narrower and peak earlier at higher energies. We also find that pulse brightness, pulse width, and pulse hardness ratios do not evolve monotonically within bursts, but that the ratios of pulse rise times to decay times tend to decrease with time within bursts.
On Recovering the Nonlinear Bias Function from Counts-in-Cells Measurements

We present a simple and accurate method to constrain galaxy bias based on the distribution of counts in cells. The unique feature of our technique is that it is applicable to nonlinear scales, where both dark matter statistics and the nature of galaxy bias are fairly complex. First, we estimate the underlying continuous distribution function from precise counts-in-cells measurements, assuming local Poisson sampling. Then a robust, nonparametric inversion of the bias function is recovered from the comparison of the cumulative distributions in simulated dark matter and galaxy catalogs. Obtaining continuous statistics from the discrete counts is the most delicate and novel part of our recipe, which corresponds to a deconvolution of a (Poisson) kernel. For this we present two alternatives: a model-independent algorithm based on Richardson-Lucy iteration, and a solution using a parametric skewed lognormal model. We find that the latter is an excellent approximation for the dark matter distribution, but the model-independent iterative procedure is more suitable for galaxies. Tests based on high-resolution dark matter simulations and corresponding mock galaxy catalogs show that we can reconstruct the nonlinear bias function down to highly nonlinear scales with high precision in the range of -1 ≤ δ ≤ 5. As far as the stochasticity of the bias, we have found a remarkably simple and accurate formula based on Poisson noise, which provides an excellent approximation for the scatter around the mean nonlinear bias function. In addition, we have found that redshift distortions have a negligible effect on our bias reconstruction; therefore, our recipe can be safely applied to redshift surveys.
Formation and repair of interstrand cross-links in DNA

Cellular DNA is susceptible to chemical modifications when exposed to various environmental agents, chemotherapeutic agents, or endogenous agents produced by cellular processes. The lesions produced by these chemical reactions can lead to mutations and/or cell death. Many of these lesions, in the form of base or phosphate modifications, occur on one or the other strand of DNA. Certain agents, however, including bifunctional alkylating agents, platinum compounds, and psoralen can produce covalent adducts with DNA bases on both strands of DNA, leading ultimately to the formation of interstrand cross-links (Figure 1). Interstrand cross-links prevent DNA strand separation and can thus act as absolute blocks to DNA replication and/or DNA transcription. If left intact, interstrand cross-links can lead to cell death. It has been estimated that as few as 20 interstrand cross-links in the bacterial or mammalian genome can be lethal to cells that lack the ability to remove the cross-link.1,2 It is this cytotoxic effect that forms the mechanistic basis of action of many of the anticancer drugs currently in use today.1,3-7 Open in a separate window Figure 1 Interstrand cross-linked DNA.
Theory of Supersolidity

After reviewing some experimental facts, and early theories, I sketch the Hartree-Fock description of Boson solids, emphasizing the contrast with the Fermion case in that the natural solution is a product of local wave-functions. I then investigate the Boson Hubbard model to demonstrate that the local functions are not orthogonal and exemplify a novel state of matter which has superflow but not ODLRO, below a cooperative thermal transition. I then discuss whether or not these ideas actually apply to solid He.
The Significance of Certain Critical Potentials of Mercury in Terms of Metastable Atoms and Radiation

The critical potentials of mercury, as found by Franck and Einsporn using the modified Lenard method, were studied by a further extension of this method which separated the effects due to metastable atoms and those due to true radiation. Quartz and calcite filters were interposed between the excitation system (hot-cathode and grid) and the detecting system ("photo-electric" plate and grid) of a four-electrode tube containing mercury vapor. The critical potential curves ("photo-electric" current plotted against voltage on excitation system) taken with and without these filters interposed were compared, the difference in the currents giving a measure of the relative number of metastable atoms produced at each voltage. All the breaks found by Franck and Einsporn except those at 5.76, 6.73, and 8.35 volts were found to be associated with increased production of metastable atoms. The hitherto unexplained breaks found by them at 6.04, 6.30, 7.12, 7.46, and 8.09 volts were found to be due mainly to the formation of metastable atoms. The difference between the photo-electric currents with the quartz and calcite filters interposed gave a measure of the radiation lying between $\ensuremath{\lambda}1650$ and $\ensuremath{\lambda}2200$, that is of the molecular bands $\ensuremath{\lambda}2140$ and of $\ensuremath{\lambda}1849$. The latter radiation was found to be the cause not only of the 6.7 volt break but also of that at 8.35 volts. The break at 7.73 volts is interpreted as the combined effect of radiation due to excitation at 7.69 volts and at 7.83 volts. The use of "photo-electric" plates of metals with different photo-electric characteristics gave further checks on the above conclusions.
Coordinate descent algorithms

Coordinate descent algorithms solve optimization problems by successively performing approximate minimization along coordinate directions or coordinate hyperplanes. They have been used in applications for many years, and their popularity continues to grow because of their usefulness in data analysis, machine learning, and other areas of current interest. This paper describes the fundamentals of the coordinate descent approach, together with variants and extensions and their convergence properties, mostly with reference to convex objectives. We pay particular attention to a certain problem structure that arises frequently in machine learning applications, showing that efficient implementations of accelerated coordinate descent algorithms are possible for problems of this type. We also present some parallel variants and discuss their convergence properties under several models of parallel execution.
New algebraic formulation of density functional calculation

This article addresses a fundamental problem faced by the community employing single-particle ab initio methods: the lack of an effective formalism for the rapid exploration and exchange of new methods. To rectify this, we introduce a new, basis-set independent, matrix-based formulation of generalized density functional theories which reduces the development, implementation, and dissemination of new techniques to the derivation and transcription of a few lines of algebra. This new framework enables us to concisely demystify the inner workings of fully functional, highly efficient modern ab initio codes and to give complete instructions for their construction for calculations employing arbitrary basis sets. Within this framework, we also discuss in full detail a variety of leading-edge techniques, minimization algorithms, and highly efficient computational kernels for use with scalar as well as shared and distributed-memory supercomputer architectures.
Mixing of the upper triangular matrix walk

We study a natural random walk over the upper triangular matrices, with entries in the field \({\mathbb{Z}_2}\) , generated by steps which add row i + 1 to row i. We show that the mixing time of the lazy random walk is O(n2) which is optimal up to constants. Our proof makes key use of the linear structure of the group and extends to walks on the upper triangular matrices over the fields \({\mathbb{Z}_q}\) for q prime.
Malignant pericardial diseases: Diagnosis and treatment

Abstract Pericardial involvement in malignant diseases is fairly common. Usually the various clinical presentations—effusion, tamponade, constriction—occur in patients with known malignancy. Primary malignancy of the pericardium is rare, whereas secondary tumor involvement of the pericardium is more frequently observed. The common secondary solid tumors involving the pericardium are from lung and breast carcinomas; of the nonhematologic malignancies, lymphomas and leukemias are most frequent. A high index of suspicion in patients with malignancy, along with a history, physical examination, x-ray films, ECG, and echocardiography, will often make the diagnosis in a hemodynamically compromised patient. Occasionally, cardiac catheterization and pericardial biopsy are necessary to differentiate malignant pericardial disease from radiation pericarditis and restrictive heart disease. Therapy is dependent on the underlying condition and includes pericardiectomy, chemotherapy to obliterate the pericardial space, and external beam radiotherapy. These therapies are all palliative, but provide months of hemodynamic relief. The underlying prognosis of malignant pericardial disease remains grave.
Hypogonadism Caused by a Single Amino Acid Substitution in the β Subunit of Luteinizing Hormone

INFERTILITY occurs in approximately 10 to 20 percent of couples and can be attributed to a reproductive disorder in the man or woman with equal frequency.1 , 2 Among men, specific causes of infertility can be identified in only a minority.1 In a previously identified kindred in which several men were infertile, the proband had not undergone spontaneous puberty and had low testosterone and elevated luteinizing hormone concentrations in serum, a pattern of hormone values indicative of primary hypogonadism.3 However, testosterone secretion in response to the administration of exogenous luteinizing hormone and human chorionic gonadotropin was normal. Thus, the proband appeared to . . .
High-throughput ab initio analysis of the Bi–In, Bi–Mg, Bi–Sb, In–Mg, In–Sb, and Mg–Sb systems

Abstract Prediction and characterization of crystal structures of alloys are a key problem in materials research. Using high-throughput ab initio calculations we explore the low-temperature phase diagrams for the following systems: Bi–In, Bi–Mg, Bi–Sb, In–Mg, In–Sb, and Mg–Sb. For the experimentally observed phases in these systems we provide information about their stability at low temperatures.
Picture information measures for similarity retrieval

Abstract A family of picture information measures based upon the concept of the minimum number of gray level changes to convert a picture into one with a desired histogram is presented. This family of picture information measures is found to satisfy a number of axions and useful inequalities. A natural extension to a Lorenz information measure is discussed. Based upon these information measures, a structural information measure can also be defined for logical pictures. Application to similarity retrieval in a pictoral information system are then suggested.
Aerodynamic Parameter Estimation for High-Performance Aircraft Using Extended Kalman Filtering

The estimation of aerodynamic coefficients in aircraft dynamic models from flight-test data is addressed in this paper. An extended Kalman filter (EKF), implementing the full nonlinear kinematics of the aircraft equations of motion, was used for this purpose. Flight-test data from NASA's X-31 Drop Model and High Angle-of-attack Research Vehicle (HARV) were analyzed. The EKF parameter estimates for the X-31 compared well with wind-tunnel data and flight-data results using other identification techniques. For the HARV, the assumption of pseudonoise in the parameter dynamic model substantially improved the state and parameter estimates. A residual correlation method was used to estimate the process noise intensity matrix for this aircraft's flight data.
Diode-Laser Sensors for Real-Time Control of Pulsed Combustion Systems

A diode-laser based, closed-loop control system has been developed to nonintrusively optimize a pulsed, 50-kW dump combustor. The adaptive control system used temperature and water mole fraction measurements obtained at 10-kHz rates from the peak absorbance values of H 2 O features near 1.4 μm. In addition, measurements of CO, C 2 H 2 , and C 2 H 4 concentrations in the exhaust, determined from diode-laser absorption spectra recorded using a fast-sampling probe and a multipass absorption cell (nominal 33-m-long path), were used to evaluate the effectiveness of the control strategies. A correlation was established between the magnitude of the observed temperature oscillations and the measured CO concentration in the exhaust. Adaptive control strategies were then applied to maximize the coherence of the burning vortices in the combustion region and thus optimize the combustor performance. The closed-loop control system was able to adaptively tune the phase and amplitude of the applied forcing within 100 ms and the forcing frequency within 10 s. These results demonstrate the applicability of multiplexed diode-laser absorption sensors for rapid, continuous measurements and control of multiple flowfield parameters, including trace species concentrations, in high-temperature combustion environments.
Grouped effects estimators in fixed effects models

Abstract We consider estimation of nonlinear panel data models with common and individual specific parameters. Fixed effects estimators are known to suffer from the incidental parameters problem, which can lead to large biases in estimates of common parameters. Pooled estimators, which ignore heterogeneity across individuals, are also generally inconsistent. We assume that individuals in the data are grouped on multiple levels where groups are defined by some observable external classification. We consider “group effects” estimators, where individual specific parameters are assumed common across groups at some level. We provide conditions under which group effects estimates of common parameters are asymptotically unbiased and normal. The conditions suggest a tradeoff between two sources of bias, one due to incidental parameters and the other due to misspecification of unobserved heterogeneity.
Syntheses and Structure-Activity Relationships of Novel 3'-Difluoromethyl and 3'-Trifluoromethyl-Taxoids.

Abstract A series of novel 3′-difluoromethyl-taxoids and 3′-trifluoromethyl-taxoids with modifications at the C2 and C10 positions were synthesized and evaluated for their in vitro cytotoxicities against human breast carcinoma (MCF7-S, MCF7-R, LCC6-WT, LCC6-MDR), non-small cell lung carcinoma (H460) and colon adenocarcinoma (HT-29) cell lines. These second-generation fluoro-taxoids exhibited several times to more than 20 times better potency than paclitaxel against drug-sensitive cancer cell lines, MCF7-S, LCC6-WT, H460, and HT-29. These fluoro-taxoids also possess two orders of magnitude higher potency than paclitaxel against drug-resistant cancer cell lines, MCF7-R and LCC6-MDR. Structure–activity relationship study shows the importance of the C10 modification for increasing the activity against multidrug-resistant cancer cell lines. Effects of the C2-benzoate modifications on the potency in the 3′-difluoromethyl-taxoid series are very clear (i.e., F 3 ), while those in the 3′-trifluoromethyl-taxoid series are less obvious. Also, different trends in the sensitivity to the C2-substitution are observed between drug-sensitive cell lines and drug-resistant cancer cell lines that overexpress efflux pumps.
ON THE ANOMALOUS RADII OF THE TRANSITING EXTRASOLAR PLANETS

We present a systematic evaluation of the agreement between the observed radii of 90 well-characterized transiting extrasolar giant planets and their corresponding model radii. Our model radii are drawn from previously published calculations of coreless giant planets that have attained their asymptotic radii, and which have been tabulated for a range of planet masses and equilibrium temperatures. (We report a two-dimensional polynomial fitting function that accurately represents the models.) As expected, the model radii provide a statistically significant improvement over a null hypothesis that the sizes of giant planets are completely independent of mass and effective temperature. As is well known, however, fiducial models provide an insufficient explanation; the planetary radius anomalies, , are strongly correlated with planetary equilibrium temperature. We find that the radius anomalies have a best-fit dependence, , with α = 1.4 ± 0.6. Incorporating this relation into the model radii leads to substantially less scatter in the radius correlation. The extra temperature dependence represents an important constraint on theoretical models for hot Jupiters. Using simple scaling arguments, we find support for the hypothesis of Batygin & Stevenson that this correlation can be attributed to a planetary heating mechanism that is mediated by magnetohydrodynamic coupling between the planetary magnetic field and near-surface flow that is accompanied by ohmic dissipation at adiabatic depth. Additionally, we find that the temperature dependence is likely too strong to admit kinetic heating as the primary source of anomalous energy generation within the majority of the observed transiting planets.
Performance enhancement of a multiple model adaptive estimator

We describe performance improvement techniques for a multiple model adaptive estimator (MMAE) used to detect and identify control surface and sensor failures on an unmanned flight vehicle. Initially failure identification was accomplished within 4 s of onset, but by removing the "/spl beta/ dominance" effects, bounding the hypothesis conditional probabilities, retuning the Kalman filters, increasing the penalty for measurement residuals, decreasing the probability smoothing, and increasing residual propagation, the identification time was reduced to 2 s. >
Depreciation and Valuation for Rate Control

I. Introductory: The problem of depreciation, 185. — II. The case against accrued depreciation, 189. — III. Current criticisms of Allison's argument, 191. — IV. Depreciation where the rates are based on the strict investment principle, 195. — V. Depreciation where the rates are based on cost of reproduction as a measure of "present value," 198. — VII. Depreciation where the rates are based on actual cost of the present property. The "historical-cost" basis, 207. — Conclusions, 211.
The first metal-catalyzed intramolecular [5+2] cycloadditions of vinylcyclopropanes and alkenes: Scope, stereochemistry, and asymmetric catalysis

Abstract The first studies of the metal-catalyzed [5+2] cycloadditions of vinylcyclopropanes and alkenes are described. These reactions proceed with exceptional diastereoselectivity and in good to excellent yields. The effect of tether and substituent variations are examined. In addition, preliminary studies show that enantioselective cycloadditions can be achieved through the use of catalysts modified with chiral phosphine ligands. This novel, general, and efficient procedure provides a fundamentally new approach to the synthesis of a variety of products of structural and medicinal significance.
Lattice-Based High-Dimensional Gaussian Filtering and the Permutohedral Lattice

High-dimensional Gaussian filtering is a popular technique in image processing, geometry processing and computer graphics for smoothing data while preserving important features. For instance, the bilateral filter, cross bilateral filter and non-local means filter fall under the broad umbrella of high-dimensional Gaussian filters. Recent algorithmic advances therein have demonstrated that by relying on a sampled representation of the underlying space, one can obtain speed-ups of orders of magnitude over the naive approach. The simplest such sampled representation is a lattice, and it has been used successfully in the bilateral grid and the permutohedral lattice algorithms. In this paper, we analyze these lattice-based algorithms, developing a general theory of lattice-based high-dimensional Gaussian filtering. We consider the set of criteria for an optimal lattice for filtering, as it offers a good tradeoff of quality for computational efficiency, and evaluate the existing lattices under the criteria. In particular, we give a rigorous exposition of the properties of the permutohedral lattice and argue that it is the optimal lattice for Gaussian filtering. Lastly, we explore further uses of the permutohedral-lattice-based Gaussian filtering framework, showing that it can be easily adapted to perform mean shift filtering and yield improvement over the traditional approach based on a Cartesian grid.
Commensurability classes of 2-bridge knot complements

We show that a hyperbolic 2‐bridge knot complement is the unique knot complement in its commensurability class. We also discuss constructions of commensurable hyperbolic knot complements and put forth a conjecture on the number of hyperbolic knot complements in a commensurability class. 57M25, 57M10; 57M27