cssi/SciSciGPT-SciSciNet huggingface dataset:
Clinical Characteristics of Clear Cell Carcinoma of the Ovary

Abstract Objective. The aim of this study is to evaluate the clinical characteristics of clear cell carcinoma of the ovary. Methods. Between 1986 and 1996, 45 patients with clear cell carcinoma of the ovary were identified by scanning the medical records department and the tumor registry at our institution. Results. Median age was 55 years (range 31–80 years). Tumors were 60% (27/45) stage I, 11% (5/45) stage II, 20% (9/45) stage III, and 9% (4/45) stage IV. All patients presented with a pelvic mass ranging in size from 2 × 3 to 20 × 30 cm and all except 1 had optimal cytoreduction. All patients received postoperative platinum-based chemotherapy, 47% (21/45) in combination with paclitaxel. One stage Ia patient refused therapy. Of the 6 stage III/IV patients with measurable residual tumor, 67% (4/6) partially responded to first line chemotherapy by CT scan or second look laparotomy. Recurrences occurred in 37% (10/27) stage I patients, including 18% (2/11) stage Ia, 33% (1/3) stage Ib, and 54% (7/13) stage Ic. Time to recurrence was 16 and 38 months for the two stage Ia patients and 35 months (median, range 18–56 months) for the stage Ic patients. Survival after recurrence was significantly related to disease-free interval after primary chemotherapy. With a median follow-up of 40 months (range 4–145 months), 93% (25/27) of stage I patients are alive, 20% (5/25) with disease, while 46% (6/13) of stage III/IV patients are alive. Median survival for the stage III/IV patients was 22 months (range 4–70 months). Conclusions. Clear cell tumors of ovary frequently present at early stages. However, these tumors have a propensity for recurrence even after primary chemotherapy in early stage tumors.
Diffusive relaxation of stress concentrations at grain boundary cavities in elevated temperature creep

Abstract This work deals with certain aspects of elevated temperatures creep cavitation of grain boundaries under cyclic and rapidly applied loading. The response of partially damaged materials (where damage is represented as crack-like cavities on the grain boundaries) following load alterations at temperatures in the vicinity of 0.5 T m or higher is analyzed. The interaction between grain boundary diffusion and elastic deformation is important in alleviating local stress concentrations under these conditions. The stress levels considered are assumed to be low enough that plastic deformation is significant. Diffusive processes contribute to high temperature creep rupture by material redistribution from the void surfaces to the grain boundaries, and any non-uniform matter accommodation along the grain boundaries is accomplished by elastic deformation under the conditions assumed. The same material redistribution mechanism dominates in the stress relaxation process. The analysis of the stress and displacement fields is based on consideration of the coupled elasticity-diffusion boundary value problem, which leads to an integral equation. On the basis of the solution obtained, the detailed analysis of the process under cyclic, step and ramp loadings is given. For suddenly applied loading the results demonstrate that the elastic stress concentration is effectively relaxed by diffusion after t = 0.05 τ where τ ≈ L 3 DE , L is half of the distance between adjacent tips of neighboring cracks along the grain boundary, E is Young's modulus, and D is diffusion parameter relating volumetric flux along the grain boundary to the stress gradient. By t = 0.25 τ the stress distribution becomes essentially identical to that calculated for rigid grains, i.e. diffusion has become the dominant process and elastic deformability of the adjoining grains is then irrelevant.
The Mathematical Theory of Black Holes

In a course of lectures on the ‘underlying mathematical structures of classical gravitation theory’ given in 1978, Brandon Carter began with the statement ‘If I had been asked five years ago to prepare a course of lectures on recent developments in classical gravitation theory, I would not have hesitated on the classical theory of black holes as a central topic of discussion. However, the most important developments in gravitational theory during the last three or four years have not been in the classical domain at all…’ Carter is undoubtedly right in his assessment that the mathematical theory of black holes has not been in the mainstream of research in relativity since 1973. I therefore find it difficult to understand why the organizers of this meeting should have chosen precisely this topic for the opening talk of this meeting. But I am grateful to them for their courtesy in assigning to me this privilege.
Allene functionalization via bicyclic methylene aziridines.

The oxidative functionalization of olefins is a common method for the formation of vicinal carbon−heteroatom bonds. However, oxidative methods to transform allenes into synthetic motifs containing three contiguous carbon−heteroatom bonds are much less developed. This paper describes the use of bicyclic methylene aziridines (MAs), prepared via intramolecular allene aziridination, as scaffolds for functionalization of all three allene carbons.
Cell association and handover management in femtocell networks

Although the technology of femtocells is highly promising, many challenging problems should be addressed before fully harvesting its potential. In this paper, we investigate the problem of cell association and handover management in femtocell networks. Two extreme cases for cell association are first discussed and analyzed. Then we propose our algorithm to maximize network capacity while achieving fairness among users. Based on this algorithm, we further develop a handover algorithm to reduce the number of unnecessary handovers using Bayesian estimation. The proposed handover algorithm is demonstrated to outperform a heuristic scheme with considerable gains in our simulation study.
Multi-track map matching

We study algorithms for matching user tracks, consisting of time-ordered location points, to paths in the road network. Previous work has focused on the scenario where the location data is linearly ordered and consists of fairly dense and regular samples. In this work, we consider the multi-track map matching, where the location data comes from different trips on the same route, each with very sparse samples. This captures the realistic scenario where users repeatedly travel on regular routes and samples are sparsely collected, either due to energy consumption constraints or because samples are only collected when the user actively uses a service. In the multi-track problem, the total set of combined locations is only partially ordered, rather than globally ordered as required by previous map-matching algorithms. We propose two methods, the iterative projection scheme and the graph Laplacian scheme, to solve the multi-track problem by using a single-track map-matching subroutine. We also propose a boosting technique which may be applied to either approach to improve the accuracy of the estimated paths. In addition, in order to deal with variable sampling rates in single-track map matching, we propose a method based on a particular regularized cost function that can be adapted for different sampling rates and measurement errors. We evaluate the effectiveness of our techniques for reconstructing tracks under several different configurations of sampling error and sampling rate.
Asymmetric induction in the formal iron-catalyzed [4 + 4] ene reaction: the highly diastereoselective cross-coupling of 1,3-dienes to chiral cyclic acetals

Etude de la reaction de dihydro-4,7 dioxepinnes-1,3 substitues en -2 ou en -4 avec le dimethyl-2,3 butadiene-1,3
Trichotomy and dichotomy results on the complexity of reasoning with disjunctive logic programs

We present trichotomy results characterizing the complexity of reasoning with disjunctive logic programs. To this end, we introduce a certain definition schema for classes of programs based on a set of allowed arities of rules. We show that each such class of programs has a finite representation, and for each of the classes definable in the schema, we characterize the complexity of the existence of an answer set problem. Next, we derive similar characterizations of the complexity of skeptical and credulous reasoning with disjunctive logic programs. Such results are of potential interest. On the one hand, they reveal some reasons responsible for the hardness of computing answer sets. On the other hand, they identify classes of problem instances, for which the problem is "easy" (in P) or "easier than in general" (in NP). We obtain similar results for the complexity of reasoning with disjunctive programs under the supported-model semantics.
Morphology of Surfaces Generated by Circular Wire Brushes

The characteristic surface that is generated during orthogonal wire brushing of a flat 6061-T6 aluminum workpart is examined in this paper. Scanning electron microscopy is used for characterizing the surface topography, whereas subsurface microstructure and properties of the brushed region are evaluated by both metallography and microhardness measurements. The unique topographical characteristics of the contact zone suggest material removal and subsequent redeposition onto the workpart. On the basis of the experimental observations, a qualitative theory is advanced which identifies transfer mechanisms for removal and redeposition of aluminum alloy
Efficient simulation and conditional functional limit theorems for ruinous heavy-tailed random walks

Abstract The contribution of this paper is to introduce change of measure based techniques for the rare-event analysis of heavy-tailed random walks. Our changes of measures are parameterized by a family of distributions admitting a mixture form. We exploit our methodology to achieve two types of results. First, we construct Monte Carlo estimators that are strongly efficient (i.e. have bounded relative mean squared error as the event of interest becomes rare). These estimators are used to estimate both rare-event probabilities of interest and associated conditional expectations. We emphasize that our techniques allow us to control the expected termination time of the Monte Carlo algorithm even if the conditional expected stopping time (under the original distribution) given the event of interest is infinity–a situation that sometimes occurs in heavy-tailed settings. Second, the mixture family serves as a good Markovian approximation (in total variation) of the conditional distribution of the whole process given the rare event of interest. The convenient form of the mixture family allows us to obtain functional conditional central limit theorems that extend classical results in the literature.
Strongly coupled N=1 SYM theory on the lattice

Abstract We propose a strong coupling expansion as a possible tool to obtain qualitative and quantitative informations about N=1 SYM theory. We point out the existence of a mapping between strongly coupled lattice N=1 SYM theory and a generalized SO(4) antiferromagnetic spin system
Cycles in dense digraphs

Let G be a digraph (without parallel edges) such that every directed cycle has length at least four; let β(G) denote the size of the smallest subset X ⊆ E(G) such that G∖X has no directed cycles, and let γ(G) be the number of unordered pairs {u, v} of vertices such that u, v are nonadjacent in G. It is easy to see that if γ(G) = 0 then β(G) = 0; what can we say about β(G) if γ(G) is bounded?
Periodic differential difference equations

This chapter presents the periodic differential difference equations. It presents a scalar equation x ( t ) = ( t ) x ( t – Δ j ), where the p j are continuous real-valued periodic functions of period w and 0 = Δ 0 1 n . In the usual way, x t = x ( t, θ, ζ, τ ) for θ ∈ [ , 0] and t ≥ τ denotes an element of C [− Δ n , 0], and the translation map U is a compact map of C [− Δ n − 0], with the uniform norm, into itself if w ≥ Δ n . If w n , then a suitable power of U is compact and the results are essentially the same. As U is compact, there is for each characteristic multiplier γ an integer n ( γ ) = dim null space ( U− γl ) m for all m > m 0 ( γ ) and a basis Φ 1 ,…, Φ n ( γ ) for this null space. For any characteristic multiplier γ and associated basis element Φ , the solution x ( t, Φ, 0) is referred to as a solution of Floquet type.
ASPHERICAL CORE-COLLAPSE SUPERNOVAE IN RED SUPERGIANTS POWERED BY NONRELATIVISTIC JETS

We explore the observational characteristics of jet-driven supernovae (SNe) by simulating bipolar-jet-driven explosions in a red supergiant (RSG) progenitor. We present results of four models in which we hold the injected kinetic energy at a constant 1051 erg across all jet models but vary the specific characteristics of the jets to explore the influence of the nature of jets on the structure of the SN ejecta. We evolve the explosions past shock-breakout and into quasi-homologous expansion of the SN envelope into a RSG wind. The simulations have sufficient numerical resolution to study the stability of the flow. Our simulations show the development of fluid instabilities that produce pristine helium clumps in the hydrogen envelope. The oppositely directed, nickel-rich jets give a large-scale asymmetry that may account for the nonspherical excitation and substructure of spectral lines such as Hα and He I 10830 A. Jets with a large fraction of kinetic to thermal energy punch through the progenitor envelope and give rise to explosions that would be observed to be asymmetric from the earliest epochs, inconsistent with spectropolarimetric measurements of Type II SNe. Jets with higher thermal energy fractions result in explosions that are roughly spherical at large radii but are significantly elongated at smaller radii, deep inside the ejecta, in agreement with the polarimetric observations. We present shock-breakout light curves that indicate that strongly aspherical shock breakouts are incompatible with recent Galaxy Evolution Explorer observations of shock breakout from RSG stars. Comparison with observations indicates that jets must deposit their kinetic energy efficiently throughout the ejecta while in the hydrogen envelope. Thermal-energy-dominated jets satisfy this criterion and yield many of the observational characteristics of Type II SNe.
Applications of heterogeneous catalysis in the direct oxidation of hydrocarbons in a solid-oxide fuel cell

This review article provides an overview of our recent studies of the direct oxidation of hydrocarbons in solid-oxide fuel cells. The use of a thermally stable, highly porous, yttria-stabilized zirconia (YSZ) matrix, which allows for the optimization of the anode composition and catalytic properties, is described. Studies of the direct oxidation of hydrocarbons using anodes composed of mixtures of YSZ, copper, ceria and samaria-doped ceria are also presented. The results of these studies demonstrate that copper-ceria based anodes are active for the direct electrocatalytic oxidation of a wide range of hydrocarbons including alkanes, alkenes, and aromatics.
Malpractice Reform — Opportunities for Leadership by Health Care Institutions and Liability Insurers

Innovative malpractice reforms can be implemented by health care institutions and liability insurers without requiring changes in the law. Michelle Mello and Dr. Thomas Gallagher focus on emerging models of disclosure of medical injuries and early resolution of cases (“disclosure and offer“ programs).
Not every pseudoalgebra is equivalent to a strict one

Abstract We describe a finitary 2-monad on a locally finitely presentable 2-category for which not every pseudoalgebra is equivalent to a strict one. This shows that having rank is not a sufficient condition on a 2-monad for every pseudoalgebra to be strictifiable. Our counterexample comes from higher category theory: the strict algebras are strict 3-categories, and the pseudoalgebras are a type of semi-strict 3-category lying in between Gray-categories and tricategories. Thus, the result follows from the fact that not every Gray-category is equivalent to a strict 3-category, connecting 2-categorical and higher-categorical coherence theory. In particular, any nontrivially braided monoidal category gives an example of a pseudoalgebra that is not equivalent to a strict one.
Trapped ion imaging with a high numerical aperture spherical mirror

Efficient collection and analysis of trapped ion qubit fluorescence is essential for robust qubit state detection in trapped ion quantum computing schemes. We discuss simple techniques of improving photon collection efficiency using high numerical aperture (N.A.) reflective optics. To test these techniques we placed a spherical mirror with an effective N.A. of about 0.9 inside a vacuum chamber in the vicinity of a linear Paul trap. We demonstrate stable and reliable trapping of single barium ions, in excellent agreement with our simulations of the electric field in this setup. While a large N.A. spherical mirror introduces significant spherical aberration, the ion image quality can be greatly improved by a specially designed aspheric corrector lens located outside the vacuum system. Our simulations show that the spherical mirror/corrector design is an easy and cost-effective way to achieve high photon collection rates when compared to a more sophisticated parabolic mirror setup.
Enhancing fault tolerance capabilities in quorum-based cycle routing

In this paper we propose a generalized R redundancy cycle technique that provides optical networks almost fault-tolerant communications. More importantly, when applied using only single cycles rather than the standard paired cycles, the generalized R redundancy technique is shown to almost halve the necessary light-trail resources in the network while maintaining the fault-tolerance and dependability expected from cycle-based routing. For efficiency and distributed control, it is common in distributed systems and algorithms to group nodes into intersecting sets referred to as quorum sets. Optimal communication quorum sets forming optical cycles based on light-trails have been shown to flexibly and efficiently route both point-to-point and multipoint-to-multipoint traffic requests. Commonly cycle routing techniques will use pairs of cycles to achieve both routing and fault-tolerance, which uses substantial resources and creates the potential for underutilization. Instead, we intentionally utilize R redundancy within the quorum cycles for fault-tolerance such that every point-to-point communication pairs occur in at least R cycles. The result is a set of R = 3 redundant cycles with 93.23–99.34% fault coverage even with two simultaneous faults all while using 38.85–42.39% fewer resources.
Development of an Integrated Course in Accounting: A Focus on Environmental Issues

Environmental issues provide a unique, timely, and important focus for an integrated course in accounting and demonstrate how accounting information is, or can be, used to support corporate environmental strategy and assess environmental performance. This type of course offers an opportunity to add value to the educational experience of both accounting and nonaccounting majors. In this article, we describe the development and structure of one such course, discuss our experiences in offering it, and summarize the perceived benefits and difficulties associated with this endeavor. Overall, we conclude that, despite some challenges in designing and offering this type of course, the benefits are significant from both instructional and professional development points of view. Furthermore, the course attempts to achieve several of the objectives laid out a decade ago by the Accounting Education Change Commission (AECC) and more recently, by the American Institute of Certified Public Accountants (AICPA) in its fo...
Electromagnetic Counterparts to Black Hole Mergers

During the final moments of a binary black hole (BH) merger, the gravitational wave (GW) luminosity of the system is greater than the combined electromagnetic (EM) output of the entire observable universe. However, the extremely weak coupling between GWs and ordinary matter makes these waves very difficult to detect directly. Fortunately, the inspiraling BH system will interact strongly—on a purely Newtonian level—with any surrounding material in the host galaxy, and this matter can in turn produce unique EM signals detectable at Earth. By identifying EM counterparts to GW sources, we will be able to study the host environments of the merging BHs, in turn greatly expanding the scientific yield of a mission like LISA. Here we present a comprehensive review of the recent literature on the subject of EM counterparts, as well as a discussion of the theoretical and observational advances required to fully realize the scientific potential of the field.
Multimedia network protocols: where are we?

Protocols for multimedia communication are needed to integrate into a single network services intended to satisfy the different requirements of multiple types of traffic. An essential prerequisite for designing these protocols is that the services to be offered by the network must be selected and specified in detail. We present the service models proposed, or being developed, by the Internet community, by the ATM community, and by the Tenet Group. We compare their common characteristics, which reveal the characteristics of the first integrated services networks are likely to offer. The services referred to in this paper are those at the network and transport layers, which support the services to be offered to the system's end users.
Fetal biophysical profile: a critical appraisal

In medicine, in general and fetal medicine in particular, the conceptual development and emerging application of a new diagnostic modality is fuelled firstly by a general recognition of the increasing relative importance of a particular clinical problem and then by critical examination of the body of scientific observation, often disparate in origin, that provides the key insights into the pathophysiology, manifestation and natural history of the disease process. So it is with the evolution of the fetal biophysical profile score. In general terms, until the 1950's the major goal of obstetric care was the prevention of maternal mortality and morbidity. As the result of a host of clinical advances including improved anaesthesia and surgical techniques and availability of blood and blood products, antibiotics and specific other drugs (oxytocin, anticonvulsants, antihypertensives, insulin etc.) maternal mortality declined to the low rates of the present day. Consequently, the focus of obstetric care shifted to the recognition and prevention of death or damage affecting the other patient in the obstetric dyad: the fetus. The first methods for evaluation of antepartum fetal health care were based on measurements of biochemical variables in the maternal compartment (e.g. oestriol, placental lactogen, alkaline phosphatase and oxytocinase).
Measures of technical efficiency

Abstract Fare and Lovell (J. Econom. Theory 19 (1978), 150–162) suggest four properties that a measure of technical efficiency should satisfy; the commonly employed Debreu-Farrell measure fails three of them. Necessary and sufficient conditions for a measure to satisfy the four conditions are provided and recently proposed measures are analyzed in the light of this result. Also, it is argued that the Debreu-Farrell measure has several desirable properties when one takes account of (1) (perhaps unknown) market prices and the relationship between technical and economic efficiency and (2) its characterization as a measure of economic efficiency using the shadow prices implicit in the production technology.
Are Donor Countries Giving More or Less Aid

The volume of foreign aid has increased during the last four decades, albeit with interruptions in certain years. Over time, the major recipients have changed: while the share of aid to Asia has diminished since the 1980s, that destined for sub-Saharan Africa has grown. There is some evidence that, since the late 1990s, debt relief has assumed a larger share of the increased aid flows to sub-Saharan Africa. The share of technical cooperation—a component of aid that is viewed as being driven by donors—has risen. More recently, there has been an increased emphasis on providing budget support to recipient governments, especially in the form of debt relief. Donor harmonization, national ownership of development plans, and sound policies on the part of the recipients are crucial for the aid to be effective in reducing poverty.
Paramagnetic reentrance effect in NS proximity cylinders

Abstract A scenario for the unusual paramagnetic reentrance behavior at ultra-low temperatures in Nb–Ag, Nb–Au, and Nb–Cu cylinders is presented. For the diamagnetic response down to temperatures of the order 15 mK, the standard theory (quasi-classical approximation) for superconductors appears to work very well, assuming that Ag, Au, and Cu remain in the normal state except for the proximity-induced superconductivity. Here it is proposed that these noble metals may become p-wave superconductors with a transition temperature of order 10 mK. Below this temperature, p-wave triplet superconductivity emerges around the periphery of the cylinder. The diamagnetic current flowing in the periphery is compensated by a quantized paramagnetic current in the opposite direction, thus providing a simple explanation for the observed increase in the susceptibility at ultra-low temperatures.
Magnetic acceleration of winds from solar-type stars

The spin-down of solar type stars (F5 V to G3 V) is generally ascribed to the outflow of magnetized plasma in the form of a wind. Magnetically coupled stellar winds are thought to provide the dominant mechanism for angular momentum loss over the entire main-sequence lifetime of stars possessing hydrogen convective zones. The associated loss in rotational kinetic energy can strongly affect the energetics of winds emanating from such stars, for sufficiently high rotation rates and magnetic field strengths. In the present paper, an attempt is made to describe qualitatively how MHD plasma outflow from a rotating star adjusts itself to a broad range of stellar conditions, including fast, intermediate, and slow magnetic rotator configurations. Using the Weber and Davis (1967) model of MHD winds, it is shown that the magnetic deceleration of an MHD wind is of importance when the loss of rotational kinetic energy due to magnetic braking exceeds the energy flux due to thermal processes alone.
An efficient method for the preparation of 2-hydroxy- and 2-aminoglycals from glycosyl sulfoxides

A new and efficient route to 2-hydroxy- and 2-aminoglycals from glycosyl sulfoxides has been developed.
Vortex Physics in Confined Geometries

Abstract Patterned irradiation of cuprate superconductors with columnar defects allows a new generation of experiments which can probe the properties of vortex liquids by forcing them to flow in confined geometries. Such experiments can be used to distinguish experimentally between continuous disorder-driven glass transitions of vortex matter, such as the vortex glass or the Bose glass transition, and non-equilibrium polymer-like glass transitions driven by interaction and entanglement. For continuous glass transitions, an analysis of such experiments that combines an inhomogeneous scaling theory with the hydrodynamic description of viscous flow of vortex liquids can be used to infer the critical behavior. After generalizing vortex hydrodynamics to incorporate currents and field gradients both longitudinal and transverse to the applied field, the critical exponents for all six vortex liquid viscosities are obtained. In particular, the shear viscosity is predicted to diverge as | T − T BG | − νz at the Bose glass transition, with ν ≃1 and z ≃4.6 the dynamical critical exponent. The scaling behavior of the AC resistivity is also derived. As concrete examples of flux flow in confined geometries, flow in a channel and in the Corbino disk geometry are discussed in detail. Finally, the implications of scaling for the hydrodynamic description of transport in the DC flux transformer geometry are discussed.
On the Mahler measure of Jones polynomials under twisting

We show that the Mahler measures of the Jones polynomial and of the colored Jones polynomials converge under twisting for any link. Moreover, almost all of the roots of these polynomials approach the unit circle under twisting. In terms of Mahler measure convergence, the Jones polynomial behaves like hyperbolic volume under Dehn surgery. For pretzel links P(a1,...,an), we show that the Mahler measure of the Jones polyno- mial converges if all ai ! 1, and approaches infinity for ai = constant if n ! 1, just as hyperbolic volume. We also show that after sufficiently many twists, the coefficient vector of the Jones polynomial and of any colored Jones polynomial decomposes into fixed blocks according to the number of strands twisted. AMS Classification 57M25; 26C10
Origin of howardites, diogenites and eucrites: A mass balance constraint

Abstract Howardite meteorites are regolith breccias (impact-produced mixtures) that consist of two main rock types: basalts that strongly resemble eucrite meteorites, and pyroxene cumulates that strongly resemble diogenite meteorites. There are basically two petrogenetic models for the noncumulate-basaltic parts of howardites: 1. (1) genesis as residual liquids of the same magma(s) that had earlier crystallized the pyroxene cumulates; and 2. (2) genesis as primary (unmodified) partial melts from the interior of the parent asteroid. A mass balance constraint, based on Al, indicates that unless the ratio (degree of melting during genesis of melts parental to pyroxene cumulates)/(degree of melting during genesis of primary basalts) was, on average, greater than about 2.8—a scenario that implies an implausible bimodality of degree of melting on the howardite parent body—an average howardite must contain more residual liquid basalt than primary basalt. If, as seems likely, eucrites (per se) are identical to the howardite basaltic components, and diogenites (per se) are the pyroxene cumulate components, then more than half of the eucrites probably formed from residual liquids of magmas that had earlier produced the diogenites. Considering all the potential complexities of petrpgenesis on the howardite parent body, neither the partial melting model nor the fractional crystallization-residual liquid model is likely “correct” for all noncumulate eucrites.
Total Synthesis of the Pseudopterane (−)-Kallolide B, the Enantiomer of Natural (+)-Kallolide B

A total synthesis of the enantiomer 35 of kallolide B was achieved starting from (S)-(−)-perillyl alcohol (8). Oxidative cleavage to the ester aldehyde 11 was effected by treatment of the epoxide 9 with H5IO6 followed by CH2N2. The allenyl ketone 13, obtained by SnCl2-promoted addition of 1-bromo-2-butyne to aldehyde 11 and subsequent Swern oxidation, cyclized to the furan 14 in the presence of catalytic AgNO3. Homologation of the derived aldehyde 15 with CBr4−Ph3P followed by n-BuLi and CH2O led to the propargylic alcohol 17. Formylation of the furan 17 (s-BuLi, DMF) and then Still−Horner−Emmons homologation yielded the (Z)-conjugated ester 22. Conversion of the propargylic alcohol function to the chloride 23 and ester reduction (DIBAL-H) furnished the chloro alcohol 24, which formed the cyclic ether 25 upon treatment with NaH. Ether 25 underwent a highly diastereoselective [2,3]Wittig ring contraction to the propargylic alcohol 26. The derived mesylate 36 was converted to the allenic ester 37 with CO an...
Theoretical Aspects of Laser-Induced Periodic Surface Structure Formation,

Abstract : Laser-induced periodic pattern formation has been observed on a variety of substances. In particular, low-power laser have been used to deposit a pattern on a metal surface. For a relatively smooth surface grating, this pattern can be explained in terms of a perturbative solution of Maxwell's equations. However, as the surface grating is enhanced by this initial deposition, the perturbation solution breaks down. An alternate non-perturbative solution of Maxwell's equations for such rough surfaces is considered here. Moreover, other possible mechanisms that may assist pattern formation are discussed, such as field-enhanced evaporation and surface migration. (Author)
Generalized Anxiety Disorder and Medical Illness

Patients with generalized anxiety disorder (GAD) often have multiple medical comorbidities. The adrenal system and genetic and environmental factors are intermediaries between anxiety and medical illnesses such as chronic pain conditions and gastrointestinal, cardiovascular, endocrine, and respiratory disorders. Medical disorders associated with anxiety include migraine, rheumatoid arthritis, peptic ulcer disease, irritable bowel syndrome, coronary heart disease, hyperthyroidism, diabetes, asthma, and chronic obstructive pulmonary disorder. Compared to people with pain conditions without GAD, individuals with pain conditions and GAD experience and register pain differently; they also have increased awareness of symptoms. Comorbid medical illnesses may influence treatment choice for GAD. Treatment of anxiety in young patients with GAD needs to be long-term to decrease vulnerability to medical conditions.
Crescent singularities in crumpled sheets

We examine the crescent singularity of a developable cone in a setting similar to that studied by Cerda et al., [Nature (London) 401, 46 (1999)]. Stretching is localized in a core region near the pushing tip and bending dominates the outer region. Two types of stresses in the outer region are identified and shown to scale differently with the distance to the tip. Energies of the $d$ cone are estimated and the conditions for the scaling of core region size ${R}_{c}$ are discussed. Tests of the pushing force equation and direct geometrical measurements provide numerical evidence that core size scales as ${R}_{c}\ensuremath{\sim}{h}^{1∕3}{R}^{2∕3}$, where $h$ is the thickness of sheet and $R$ is the supporting container radius, in agreement with the proposition of Cerda et al. We give arguments that this observed scaling law should not represent the asymptotic behavior. Other properties are also studied and tested numerically, consistent with our analysis.
MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE

Recent mid-infrared observations of young stellar objects have found significant variations possibly indicative of changes in the structure of the circumstellar disk. Previous models of this variability have been restricted to axisymmetric perturbations in the disk. We consider simple models of a non-axisymmetric variation in the inner disk, such as a warp or a spiral wave. We find that the precession of these non-axisymmetric structures produces negligible flux variations but a change in the height of these structures can lead to significant changes in the mid-infrared flux. Applying these models to observations of the young stellar object LRLL 31 suggests that the observed variability could be explained by a warped inner disk with variable scale height. This suggests that some of the variability observed in young stellar objects could be explained by non-axisymmetric disturbances in the inner disk and this variability would be easily observable in future studies.
A Practical, Two-Step Synthesis of 2-Substituted 1,3-Butadienes

A two-step procedure for preparing 2-alkyl-1,3-butadienes is described. Cuprate addition to commercially available 1,4-dibromo-2-butene yields 3-alkyl-4-bromo-1-butene, a product of SN2′ substitution. Dehydrohalogenation gives 2-alkyl-1,3-butadienes.
Molecular mechanisms of steroid hormone action

Abstract The differentiated chick oviduct is a target tissue for progesterone. Administration of the hormone to estrogen-primed chicks causes a rapid induction of new messenger RNA, resulting in the appearance in cytoplasm of specific mRNA species. One of these species is the mRNA coding for the egg white protein avidin, which is produced only in response to progesterone. The cytoplasm contains receptors which bind progesterone specifically and transport it as a complex into oviduct nuclei. Only a small fraction of the receptors are active in vitro ; this fraction is increased to 30% by brief warming of the receptor-hormone complexes before incubation with the nuclei. The binding reaction is slow, and the receptors cannot be released from nuclei by DNase treatment. The reaction occurs preferentially with oviduct nuclei, which contain at least twice as many acceptor sites (8000/nucleus) as other chick tissues ( K d ~ 10 −8 M), and are identical to the constant for receptor binding to isolated chromatin. We have isolated the progesterone receptor component which binds to the chromatin. Oviduct cytosol from laying hens was prepared and progesterone receptors were precipitated with ammonium sulfate (30% sat.). The re-dissolved pellet was eluted from a steroid-affinity column (Sepharose 4B-BSA-deoxycorticosterone) with 3M urea. The receptors were reconstituted by dialysis and labeled with [ 3 H]-progesterone. The [ 3 H]-progesterone-receptor complexes were then purified by sequential chromatography and elution with the indicated slats at pH 74 from DEAE-cellulose (0.2 M KCl), phosphocellulose (0.26 M KCl), and hydroxylapatite (0.15 M K x PO 4 ). The peak fraction was finally chromatographed on an agarose A-1.5 M column ( K av = 0.28). Yield was 1 %, and purity approached the theoretical maximum specific activity, 10 9 d.p.m./mg protein.
A fast time domain digital simulation technique for power converters: Application to a buck converter with feedforward compensation

Small-signal analysis was performed earlier to demonstrate the marked improvement of dynamic properties and stability margins of a switching regulator employing a novel feedforward input filter compensation scheme. A large-signal nonlinear recurrent time domain model is presented for the converter to analyze the transient response due to a step input change with and without the presence of the proposed feedforward loop. The results are verified with experimental data.
Violent Relaxation, Phase Mixing, and Gravitational Landau Damping

This paper outlines a geometric interpretation of flows generated by the collisionless Boltzmann equation, focusing in particular on the coarse-grained approach toward a time-independent equilibrium. The starting point is the recognition that the collisionless Boltzmann equation is a noncanonical Hamiltonian system with the distribution function f as the fundamental dynamical variable, the mean field energy [ f ] playing the role of the Hamiltonian, and the natural arena of physics being Γ, the infinite-dimensional phase space of distribution functions. Every time-dependent equilibrium f0 is an energy extremal with respect to all perturbations δf that preserve the constraints (Casimirs) associated with Liouville's theorem. If the extremal is a local energy minimum, f0 must be linearly stable, but if it corresponds instead to a saddle point, f0 may be unstable. If an initial f(t = 0) is sufficiently close to some linearly stable lower energy f0, its evolution can be visualized as involving linear phase-space oscillations about f0 which, in many cases, would be expected to exhibit linear Landau damping. If, instead, f(0) is far from any stable extremal, the flow will be more complicated, but, in general, one might anticipate that the evolution can be visualized as involving nonlinear oscillations about some lower energy f0. In this picture, the coarse-grained approach toward equilibrium usually termed violent relaxation is interpreted as nonlinear Landau damping. Evolution of a generic initial f(0) involves a coherent initial excitation δf(0) ≡ f(0) - f0, not necessarily small, being converted into incoherent motion associated with nonlinear oscillations about some f0 which, in general, will exhibit destructive interference. This picture allows for distinctions between regular and chaotic "orbits" in Γ: stable extremals f0 all have vanishing Lyapunov exponents, even though "orbits" oscillating about f0 may well correspond to chaotic trajectories with one or more positive Lyapunov exponents.
Unformatted Digital Fiber-Optic Data Transmission for Radio Astronomy Front-Ends

ABSTRACT.We report on the development of a prototype integrated receiver front-end that combines all conversions from RF to baseband, from analog to digital, and from copper to fiber into one compact assembly, with the necessary gain and stability suitable for radio astronomy applications. The emphasis in this article is on a novel digital data link over optical fiber which requires no formatting in the front-end, greatly reducing the complexity, bulk, and power consumption of digital electronics inside the antenna, facilitating its integration with the analog components, and minimizing the self-generated radio-frequency interference (RFI) which could leak into the signal path. Management of the serial data link is performed entirely in the back-end based on the statistical properties of signals with a strong random noise component. In this way, the full benefits of precision and stability afforded by conventional digital data transmission are realized with far less overhead at the focal plane of a radio ...
Morphological Annotations for Groups in the First Database

The morphology of selected groups of sources in the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) survey and catalog is examined. Sources in the FIRST catalog (2003 April release, 811,117 entries) were sorted into singles, doubles, triples, and groups of higher-count membership based on a proximity criteria. The 7106 groups with four or more components were examined individually for bent types including, but not limited to, wide-angle tail and narrow-angle tail types. In the process of this examination, ring, double-double, X-shaped, hybrid morphology, giant radio sources, and the herein described W-shaped and tri-axial morphology systems were also identified. For the convenience of the reader separate tables for distinctive types were generated. A few curiosities were found. For the 16,950 three-component groups and 74,788 two-component groups, catalogs with probability estimates for bent classification, as determined by pattern recognition techniques, are presented.
Diazaheterocycle analogues of tetracene: synthesis and properties of a naphtho-fused cinnoline and a naphtho-fused isoindazole

The synthesis and characterization of a diethynyl naphtho-fused cinnoline and isoindazole are described. The results show that both electron-accepting and electron-donating molecules can be prepared from a common intermediate.
Finite element and experimental analyses of non-axisymmetric dielectric elastomer actuators

In this paper the general-purpose finite element (FE) software ABAQUS is used to develop models to simulate large nonlinear viscoelastic response of non-axisymmetric dielectric elastomer actuators. The FE models assume the material to be a simple homogenous, isotropic, and incompressible material. The hyperelastic and viscoelastic material constants are determined using results from constant load uniaxial tensile tests and a constant load uniaxial creep test, respectively. Actuator with elliptical and rectangular cavities fabricated and tested at 5.5, 6.0, and 6.5 kV. The FE models are validated using experimental results obtained after 90 seconds.
The Formation of Low-Mass Cluster Galaxies and the Universal Initial Galaxy Mass Function

Clusters of galaxies have an observed overdensity of low-luminosity systems in comparison with the field, although it is not yet agreed whether this effect is the result of initial galaxy mass functions that vary with environment or galaxy evolutionary effects. In this Letter, we argue that this overdensity is the result of low-mass systems with red colors that are overpopulating the faint end of the observed luminosity function in the nearby rich cluster Abell 0426. We show that the luminosity function of Abell 0426 becomes steeper, from the field value α = -1.25 ± 0.05 to α = -1.44 ± 0.04, because of a recently identified population of red low-mass cluster galaxies that are possibly the remnants of dynamically stripped high-mass systems. We further demonstrate, through simple models of stripping effects, how cluster luminosity functions can become artificially steep over time from the production of these low-mass cluster galaxies.
Randomization Does Not Justify Logistic Regression

The logit model is often used to analyze experimental data. However, randomization does not justify the model, so the usual estimators can be inconsistent. A consistent estimator is proposed. Neyman’s non-parametric setup is used as a benchmark. In this setup, each subject has two potential responses, one if treated and the other if untreated; only one of the two responses can be observed. Beside the mathematics, there are simulation results, a brief review of the literature, and some recommendations for practice.
Toward red-emitting, radiation tolerant chromophores

Abstract The current state of the art of red-shifted fluorescent dyes is reviewed from the viewpoint of Superconductor Super Collider (SSC) design constraints (emission wavelength, lifetime, radiation-tolerance, quantum yield, etc.) and theoretical limitations (Einstein coefficients, natural lifetimes, oscillator strengths). Improvements to the performance of current red-emitting fluors which are simultaneously optimized to meet these constraints are needed, and the suggestion of applying computational methods to molecular design of fluorescent chromophores is presented by example. Emphasis is placed on dyes which emit at wavelengths longer than 500 nm, and in particular near 630 nm, the window of maximum transmittance of polystyrene plastic optical fiber.
Evidence for Postquiescent, High-Energy Emission from Gamma-Ray Burst 990104

It is well known that high-energy emission (MeV-GeV) has been observed in a number of gamma-ray bursts, and temporally extended emission from lower energy gamma rays through radio wavelengths is well established. An important observed characteristic of some bursts at low energy is quiescence: an initial emission followed by a quiet period before a second (postquiescent) emission. Evidence for significant high-energy, postquiescent emission has been lacking. Here we present evidence for high-energy emission, coincident with lower energy emission, from the postquiescent emission episode of the very bright and long burst, GRB 990104. We show light curves and spectra that confirm emission above 50 MeV, approximately 152 s after the BATSE trigger and initial emission episode. Between the initial emission episode and the main peak, seen at both low and high energy, there was a quiescent period of ~100 s during which the burst was relatively quiet. This burst was found as part of an ongoing search for high-energy emission in gamma-ray bursts using the EGRET fixed interval (32 s) accumulation spectra, which provide sensitivity to later, high-energy emission that is otherwise missed by the standard EGRET BATSE-triggered burst spectra.
Exploitation of parallelism in VLSI array testing

Abstract Testing of VLSI/WSI arrays using the spiral testing method is time-consuming due to its sequential nature. In this paper, we propose an efficient testing algorithm which reduces the testing time considerably and requires little hardware overhead. Fault-free data paths are identified first to obtain a high degree of parallelism in cell function unit testing. Cell functional units are then tested by using signature comparisons. Faulty cells determined to be fault-free due to fault masking are removed by subsequent comparisons of responses for every test input. A fairly general fault model is used to cover the faults in the switches and data links as well as the cell functional units.