cssi/SciSciGPT-SciSciNet huggingface dataset:
Composition, Similarity, and the Measurement of Economic Homogeneity*

. The concept of economic homogeneity in regional science is based on two very different notions: composition and similarity. In the case of the states of the US, measures of homogeneity based on these different notions are negatively correlated with each other, suggesting that the results of studies that use measures of economic homogeneity are likely to be sensitive to the conceptual basis of the specific measure. In order to overcome this problem, a portfolio-theoretic measure of economic homogeneity with some attractive properties is presented. It is naturally decomposable into two components reflecting each of these notions and easy to construct using widely available data. Using this measure, patterns of homogeneity for the states of the US are illustrated and discussed, and hypotheses about the relationship between homogeneity and economic instability are tested.
Cointegration tests of purchasing power parity

Im et al. (Unpublished working paper, 2008) develop cointegration tests using stationary instrumental variables. Their tests avoid the need to simulate critical values for the cointegration estimations, especially problematic in the presence of a nuisance parameter. Likewise, bootstrapping errors is unnecessary. Using an updated version of the Taylor (Rev Econ Stat 84(1):139–150, 2002) data set, the Im et al. (Unpublished working paper, 2008) approach is applied to two well-known, single equation cointegration methods to test for purchasing power parity. The estimations with instruments provide evidence of purchasing power parity (PPP) for more than half of the countries studied; but the empirical results, hence conclusions regarding PPP sometimes differ with the choice of instrument.
Could Prometheus be bound again? A contribution to the convergence controversy

Abstract This paper presents a neoclassical model of stochastic growth in which the probability of adverse shocks to production is inversely related to the aggregate stock of capital per capita. Postulating this endogenous relationship, justified by empirical evidence, the model yields predictions that are largely consistent with the recent findings of cross-country club convergence. Differently from the standard explanation based on multiplicity of steady states, this model is also able to yield predictions consistent with observable intra-distribution dynamics, thus accounting for phenomena such as economic miracles, growth disasters and reversals of fortune.
Algorithmic combinatorics based on slicing posets

A combinatorial problem usually requires enumerating, counting or ascertaining existence of structures that satisfy a given property B in a set of structures L. This paper describes a technique based on a generalization of Birkhoff's theorem of representation of finite distributive lattices that can be used for solving such problems mechanically and efficiently. Specifically, we give an efficient (polynomial time) algorithm to enumerate, count or detect structures that satisfy B when the total set of structures is large but the set of structures satisfying B is small. We illustrate our techniques by analyzing problems in integer partitions, set families, and set of permutations.
Concise syntheses of L-α-phosphatidyl-D-myo-inositol 3-phosphate (3- PIP), 5-phosphate (5-PIP), and 3,5-bisphosphate (3,5-PIP2)

Abstract Highly efficient, asymmetric total syntheses of the title phospholipids as well as short chain and cross-linkable aminoether analogs were achieved in five to seven steps from a readily available myo -inositol derivative.
Effects of freestream nonequilibrium on convective heat transfer to a blunt body

The axisymmetric Navier- Stokes equations are solved numerically for nonequilibrium airflows over a hemisphere. A formulation with a three-temperature thermochemical model has been employed to simulate vibrationally excited and partially dissociated airflow. A flow condition that has a total enthalpy of 25 MJ/kg and a surface pressure of 0.076 atm is studied. Computed stagnation point heat transfer using finite catalytic boundary conditions at the surface is compared with classical results. Departures from the classical heat transfer predictions caused by nonequilibrium effects are assessed for arcjet testing applications. A Damkohler number analysis is used to characterize the extent of flowfield nonequilibrium. It is shown that characterization of the thermodynamic state of the gas at the boundary-layer edge and within the boundary layer is needed to interpret the heat transfer measurements and to determine the surface catalytic efficiency.
Analysis of conformal antennas on a complex platform

A numerical technique is presented for characterizing the radiation patterns and mutual coupling of conformal antennas mounted on a complex platform. This technique uses the higher-order finite element method (FEM) to model the antennas and the platform and employs the boundary integral equation to terminate the FEM computational domain. The resulting numerical system is solved using a novel preconditioner in conjunction with the multilevel fast multipole algorithm for the fast evaluation of boundary integrals. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 139–142, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10700
New Opportunities for State Participation in the Control of Radioactive Pollution

State governments have expressed a strong desire to regulate the environmental aspects of atomic energy production, but have been prevented from assuming any role by the belief that the Atomic Energy Act of 1954 pre-empted the states' power in this area. Even though Congress has the power to preclude the states from exercising any control over atomic waste disposal, it has never expressly done so; rather, the courts have imputed this intent to Congress. Two developments which may open the door to state regulation are reviewed. The first is the passage of the 1972 Amendments to the Federal Water Pollution Control Act (FWPCA), which seemingly takes from the Atomic Energy Commission (AEC) and gives to the Environmental Protection Agency (EPA) the responsibility for control of certain radioactive materials; also under the FWPCA, the states are expressly authorized to impose stricter performance standards than the EPA. The second development is the court decision upholding the interpretation that the FWPCA conferred jurisdiction on the EPA to regulate the discharge of radioactive waste materials into navigable waters.It is concluded that there is a small possibility that the states may be allowed to play a role in atomic energy pollution control, but their rolemore » will depend upon further court and Congressional action.« less
1,2-Hydrogen shifts in thermal and photic Bamford-Stevens reactions of cyclohexanones. Activation by an endocyclic oxygen

Abstract Alkoxyl substituents are known to activate alpha H's for rearrangement to carbenic centers. In acyclic systems, the degree of transition state stabilization depends on whether the alkoxyl group positions itself syn or anti to the moiety connected to the other side of the carbenic carbon; and in cyclohexylidenes, it depends on whether the alkoxyl substituent is initially axial or equatorial on the ring. To assess the relative activating power of a tetrahydropyranyl ring oxygen we synthesized and studied a 17a-oxa-D-homo steroidal C-16 ketone ( 11a ). The carbonyl group was converted to a putative singlet carbene center by thermal and photic Bamford-Stevens (B-S) reactions, and the relative amounts of H migration from C-17 vs. C-15 were determined. The ring oxygen proved to be a more powerful activator than ring alkyl by a factor of 21:1 in thermolysis at 170 °C and ca. 14:1 in photolysis at −70 °C.
Another collision for the Coma cluster

We describe a wavelet transform analysis of the ROSAT Position Sensitive Proportional Counter images of the Coma Cluster. On small scales, ≤1', the wavelet analysis shows substructure dominated by two extended sources surrounding the two brightest cluster galaxies, NGC 4874 and NGC 4889. On slightly larger scales, ~2', the wavelet analysis reveals a filament of X-ray emission originating near the cluster's center, curving to the south and east for ~25' in the direction of the galaxy NGC 4911, and ending near the galaxy NGC 4921. These results extend earlier ROSAT observations and further indicate the complex nature of the cluster's core. We consider two possible explanations for the production of the filamentary feature from interactions of the main cluster with a merging group. The feature could arise from either ram pressure stripped gas or a dark matter perturbation of tidally stripped material.
CORRELATIONS BETWEEN ULTRAHIGH ENERGY COSMIC RAYS AND INFRARED-LUMINOUS GALAXIES

We confirm the ultrahigh energy cosmic ray (UHECR) horizon established by the Pierre Auger Observatory using the heterogeneous Veron-Cetty–Veron (VCV) catalog of active galactic nuclei by performing a redshift-angle-IR luminosity scan using point-source catalog with redshift (PSCz) galaxies having infrared luminosity greater than 1010 L ☉. The strongest correlation—for z < 0.016, ψ = 21, and L ir ≥ 1010.5 L ☉—arises in fewer than 0.3% of scans with isotropic source directions. When we apply a penalty for using the UHECR energy threshold that was tuned to maximize the correlation with VCV, the significance degrades to 1.1%. Since the PSCz catalog is complete and volume-limited for these parameters, this suggests that the UHECR horizon discovered by the Pierre Auger Observatory is not an artifact of the incompleteness and other idiosyncrasies of the VCV catalog. The strength of the correlation between UHECRs and the nearby highest-IR-luminosity PSCz galaxies is stronger than in about 90% of trials with scrambled luminosity assignments for the PSCz galaxies. If confirmed by future data, this result would indicate that the sources of UHECRs are more strongly associated with luminous IR galaxies than with ordinary, lower IR luminosity galaxies.
Theoretical Models of Young Open Star Clusters: Effects of a Gaseous Component and Gas Removal

We construct a family of semianalytic models for young open clusters, including a gaseous component and varying assumptions about the distribution function for the stellar component. The parameters of these models are informed by observed open clusters and general theoretical considerations regarding cluster formation. We use this framework to estimate the fraction * of the stellar component that remains gravitationally bound after the gaseous component disperses. The remaining stellar fraction * is a smooth function of the star formation efficiency, *, and depends on the distribution function of the stars. We calculate the function *(*) for this class of open cluster models and provide fitting formulae for representative cases.
World-volume approach to absorption by non-dilatonic branes

Abstract We calculate classical cross sections for absorption of massless scalars by the extremal 3-branes of type IIB theory, and by the extremal 2- and 5-branes of M-theory. The results are compared with corresponding calculations in the world-volume effective theories. For all three cases we find agreement in the scaling with the energy and the number of coincident branes. For 3-branes, whose stringy description is known in detail in terms of multiple D-branes, the string theoretic absorption cross section for low-energy dilatons is in exact agreement with the classical gravity. This suggests that scattering from extremal 3-branes is a unitary process well described by perturbative string theory.
Multi-country evidence on the behavior of purchasing power parity under the current float

Abstract Using panel data for the United States and 22 other OECD countries for the current float, this paper presents evidence that despite substantial short-term perturbations, purchasing power parity actually performed much better than commonly believed. Average rates of growth of real exchange rates over long horizons bear little relationship either to average rates of growth of nominal exchange rates or to average inflation differentials, thus implying a close to one-to-one relation between average rates of growth of nominal exchange rates and average inflation differentials. Panel-data variants of standard unit-root tests suggest that the real exchange rates of these countries can be characterized as mean-reverting.
Lattice QCD at finite isospin chemical potential and temperature.

We simulate lattice QCD at a finite chemical potential {mu}{sub I} for isospin (I{sub 3}) at zero and finite temperatures. At some {mu}{sub I} = {mu}c QCD has a second order transition with mean-field critical exponents to a state where (I{sub 3}) is broken spontaneously by a charged pion condensate. Heating the system with {mu}{sub I} > {mu}{sub c} we find there is some temperature at which this condensate evaporates. This transition appears to be second order and mean-field at lower {mu}{sub I} values, and first order for {mu}{sub I} sufficiently large. We are determining the dependence of the finite temperature crossover T{sub c} on {mu}{sub I} for {mu}{sub I} < {mu}{sub c}. This is expected to be identical to T{sub c}'s dependence on quark-number chemical potential {mu}{sub q} for small {mu}{sub q}.
Aligned Virtual Coordinates for Greedy Routing in WSNs

Geographic routing protocols achieve relatively good performance, and provide several advantages over conventional protocols for multihop wireless networks. However, such protocols are impacted by physical voids, and localization errors. Virtual coordinate systems (VCS) were proposed as an alternative approach that is resilient to localization errors and that naturally routes around physical voids. In this paper, we show that VCS is vulnerable to different forms of the void problem and, in general, perform worse than geographic routing in the greedy phase. We show that these anomalies arise from quantization noise in the estimate of connectivity and node location due to the integral nature of VCS co-ordinates. We propose an aligned virtual coordinate system (AVCS) on which the greedy routing success can be significantly improved. With our approach, and for the first time, we show that greedy routing on VCS outperforms that on geographic coordinates even with no localization errors. We compare AVCS against some of the most popular geometric routing protocols both using physical and virtual coordinates and show that it significantly improves performance over these solutions.
Tropospheric Effects of Satellite Power Systems

The construction and operation of a system of solar power satellites is expected to have a variety of effects on the troposphere. The launching of large space vehicles affects the air quality in the vicinity of the launch site, and the ground cloud associated with such a launch is known to stimulate the growth of water clouds under some circumstances. The transmission of power from satellite to the Earth's surface may affect certain meteorological parameters in the vicinity of the rectenna site. These and other effects are discussed in reference to the proposed solar power satellite system.
Delivery of molecular and cellular medicine to solid tumors

To reach cancer cells in a tumor, a blood-borne therapeutic molecule or cell must make its way into the blood vessels of the tumor and across the vessel wall into the interstitium, and finally migrate through the interstitium. Unfortunately, tumors often develop in ways that hinder each of these steps. Our research goals are to analyze each of these steps experimentally and theoretically, and then integrate the resulting information in a unified theoretical framework. This paradigm of analysis and synthesis has allowed us to obtain a better understanding of physiological barriers in solid tumors, and to develop novel strategies to exploit and/or to overcome these barriers for improved cancer detection and treatment.
Examining large databases: a chemometric approach using principal component analysis

Abstract Principal component analysis is used to examine large multivariate databases. The graphical approach to exploratory data analysis is described and illustrated with a single example of chemical compositions data obtained on environmental dust particles. While the graphical approach to exploratory data analysis has certain advantages over the numerical procedures, the empirical approach described here should be viewed as complementary to the more robust treatments that statistical methodologies afford.
The elusive asymptotic behavior of the high-temperature expansion of the hierarchical Ising model

We present a differential formulation of the recursion formula of the hierarchical model which provides a recursive method of calculation for the high-temperature expansion. We calculate the first 30 coefficients of the high-temperature expansion of the magnetic susceptibility of the Ising hierarchical model with 12 significant digits. We study the departure from the approximation which consists in identifying the coefficients with the values they would take if a [0, 1] Pade approximant were exact. We show that, when the order in the high-temperature expansion increases, the departure from this approximation grows more slowly than for nearest neighbor models. As a consequence, the value of the critical exponent γ estimated using Pade approximants converges very slowly and the estimations using 30 coefficients have errors larger than 0.05. A (presumably much) larger number of coefficients is necessary to obtain the critical exponents with a precision comparable to the precision obtained for nearest neighbor models with fewer coefficients. We also discuss the possibility of constructing models where a [0, 1] Pade approximant would be exact.
Sum-of-squares Lower Bounds for Planted Clique

Finding cliques in random graphs and the closely related "planted" clique variant, where a clique of size k is planted in a random G(n,1/2) graph, have been the focus of substantial study in algorithm design. Despite much effort, the best known polynomial-time algorithms only solve the problem for k = Θ(√n). In this paper we study the complexity of the planted clique problem under algorithms from the Sum-Of-Squares hierarchy. We prove the first average case lower bound for this model: for almost all graphs in G(n,1/2), r rounds of the SOS hierarchy cannot find a planted k-clique unless k ≥ (√n/log n)1/rCr. Thus, for any constant number of rounds planted cliques of size no(1) cannot be found by this powerful class of algorithms. This is shown via an integrability gap for the natural formulation of maximum clique problem on random graphs for SOS and Lasserre hierarchies, which in turn follow from degree lower bounds for the Positivestellensatz proof system.We follow the usual recipe for such proofs. First, we introduce a natural "dual certificate" (also known as a "vector-solution" or "pseudo-expectation") for the given system of polynomial equations representing the problem for every fixed input graph. Then we show that the matrix associated with this dual certificate is PSD (positive semi-definite) with high probability over the choice of the input graph.This requires the use of certain tools. One is the theory of association schemes, and in particular the eigenspaces and eigenvalues of the Johnson scheme. Another is a combinatorial method we develop to compute (via traces) norm bounds for certain random matrices whose entries are highly dependent; we hope this method will be useful elsewhere.
Cyclic maps in rational homotopy theory

The notion of a cyclic map g:A→X is a natural generalization of a Gottlieb element in πn(X). We investigate cyclic maps from a rational homotopy theory point of view. We show a number of results for rationalized cyclic maps which generalize well-known results on the rationalized Gottlieb groups.
Reconfigurable randomized K-way graph partitioning

In this paper, a randomized k-way graph partitioning algorithm is mapped onto reconfigurable hardware. The randomized algorithm relies on repetitive running of the same algorithm with different random number sequences to achieve the (near-)optimal solution. The run-time and hardware requirements of this reconfigurable solution per a random number sequence are O(|V|-K) cycles and O(|V|log|V|+|E|) gates and flip-flops, respectively. Performance is improved further at the expense of more hardware by running multiple copies of the partitioning algorithm with different random number sequences concurrently, and/or splitting a random sequence into subsequences and running them in parallel. Furthermore, in the context of this mapping, dynamic randomly configurable pattern-generation-based random number generation methods are introduced.
The dicobaltoctacarbonyl catalyzed polymerization of allylic ethers

Abstract Allylic ethers undergo spontaneous, exothermic polymerization in the presence catalytic amounts of dicobaltoctacarbonyl and silanes. Investigation of the mechanism of this new polymerization reaction indicates that the polymerization occurs by a multistep mechanism involving first, isomerization of the allylic ether to the corresponding 1-propenyl ether, then cationic polymerization of this latter species. It is proposed that two different cobalt-containing species are present which catalyze this tandem process.
Practical Implementation of Log-Scale Active Illumination Microscopy

Active illumination microscopy is a method of redistributing dynamic range in scanning microscopes using feedback for real-time control of illumination power. Images are reconstructed on a logarithmic scale to preserve dynamic range benefits.
Women and the Machine: Representations from the Spinning Wheel to the Electronic Age

Writing from the perspective of an art historian (and a former public relations person for "Playboy"), Julie Wosk examines the role of machines in helping women reconfigure and transform their lives. In this text, she takes her readers through a gallery of fiction and high and low art which depicts women in their association with machines. From sitting at the spinning wheel to typing at the typewriter, to driving automobiles, piloting airplanes, pounding rivets, and then working on the computer, Wosk tells the story of women celebrating their new liberties and growing competency but, along the way, gives interesting examples of ambivalence, male-engendered sexual fantasy, and fears of displacement. With more than 150 images, the volume presents how women and machines have appeared in (mostly male-created) art, photography, advertising and literature in America and Western Europe over the past 200 years. The book also explores the work women artists and writers have fashioned to represent their own images of machines. In dramatically contrasting views, the images Wosk has collected portray women as timid and fearful creatures, baffled by the workings of science and technology, and yet fully capable of machine mastery and control - and of making machines beguiling as products. The work illuminates popular gender stereotypes that have haunted women throughout history while underscoring the ambivalent advances women have achieved in the supposedly male world of machines.
Colliding with a crunching bubble

In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite fraction of future infinity. In this case, the crunch singularity is hidden behind the horizon of a stable hyperbolic black hole.
EXTENSIONS OF ALGEBRAIC FUNCTION FIELDS WITH COMPLETE SPLITTING OF ALL RATIONAL PLACES

We introduce the notion of "quasi-symmetric" polynomials, which is a generalization of the notion of symmetry, and is particularly suited to the setting of polynomial rings over finite fields. The properties of this new class of functions are studied. It is then shown that quasi-symmetric polynomials are very useful in splitting rational places in extensions of function fields over finite fields and thus may be used in constructing extensions with many rational places.
The Action of Acetic Acid and/or Acetic Anhydride on Either Tetraphenyltin or Diphenyltin Oxide to Form Tin(IV) Acetate

Abstract Tin(IV) acetate is prepared in nearly quantitative yield in only 4 hours from tetraphenyltin by the action of either a refluxing acetic acid-acetic anhydride mixture, or by acetic acid alone. Under anhydrous conditions neither tetraphenyltin nor diphenyltin oxide reacts with refluxing acetic anhydride alone over a period of four hours to give tin(IV) acetate. Likewise, refluxing glacial acetic acid alone with diphenyltin oxide over a period of four hours does not give tin(IV) acetate. However, it is obtained in nearly quantitative yield by the action of a refluxing acetic acid-acetic anhydride mixture on diphenyltin oxide over the same period of time.
Bulk crystal growth and electronic characterization of the 3D Dirac semimetal Na3Bi

High quality hexagon plate-like Na3Bi crystals with large (001) plane surfaces were grown from a molten Na flux. The freshly cleaved crystals were analyzed by low temperature scanning tunneling microscopy and angle-resolved photoemission spectroscopy, allowing for the characterization of the three-dimensional (3D) Dirac semimetal (TDS) behavior and the observation of the topological surface states. Landau levels were observed, and the energy-momentum relations exhibited a linear dispersion relationship, characteristic of the 3D TDS nature of Na3Bi. In transport measurements on Na3Bi crystals, the linear magnetoresistance and Shubnikov-de Haas quantum oscillations are observed for the first time.
The Citation Impact of Digital Preprint Archives for Solar Physics Papers

Papers that are posted to a digital preprint archive are typically cited twice as often as papers that are not posted. This has been demonstrated for papers published in a wide variety of journals, and in many different subfields of astronomy. Most astronomers now use the arXiv.org server (astro-ph) to distribute preprints, but the solar physics community has an independent archive hosted at Montana State University. For several samples of solar physics papers published in 2003, I quantify the boost in citation rates for preprints posted to each of these servers. I show that papers on the MSU archive typically have citation rates 1.7 times higher than the average of similar papers that are not posted as preprints, while those posted to astro-ph get 2.6 times the average. A comparable boost is found for papers published in conference proceedings, suggesting that the higher citation rates are not the result of self-selection of above-average papers.
THE WRONG WAY TO MANDALAY: THE MASSACHUSETTS SELECTIVE PURCHASING ACT AND THE CONSTITUTION

The United States cannot and should not approach the world as fifty states and thousands of municipalities who embark on setting their own foreign policy whenever it suits them.1 It's a core principle of democracy that the federal government should not intrude on state powers to spend local tax dollars unless there's an overwhelming federal interest at stake.2
Intramolecular [2 + 2] cycloaddition and sequential ring expansion

Abstract Free radical ring expansion of fused-cyclobutanones gives bicyclic ketones expanded by three and four carbons, with the carbonyl group β to the ring junction. Four-carbon ring expansion shows stereoselectivity favoring the trans-fused product 6-trans . The radical precursor cyclobutanones are readily prepared by intramolecular [2 + 2] cycloaddition of ketenes or keteniminium salts to olefins.
Film Cooling of a Turbine Blade With Injection Through Two Rows of Holes in the Near-Endwall Region

Measurements of film cooling on a simulated turbine blade are conducted using a mass transfer technique. Under the influence of the endwall, dramatic changes of film cooling performance occur on the convex surface of the blade as compared to the region where the flow is two dimensional. The result is a triangular region, where coolant is swept away from the surface by the three-dimensional vortex-driven flow present between adjacent blades. In order to predict the area of this unprotected region, the influences of several parameters including density ratio, blowing rate, and number of rows of injection holes are studied. The presence of the endwall affects the film cooling performance on the concave surface only slightly.
Legendrian knots, transverse knots and combinatorial Floer homology

Using the combinatorial approach to knot Floer homology, we define an invariant for Legendrian knots in the three-sphere, which takes values in link Floer homology. This invariant can be used to also construct an invariant of transverse knots.
Ddbx-LPP: a dynamic software tool for debugging asynchronous distributed algorithms on loosely coupled parallel processors

Abstract It is generally accepted in the parallel processing community that powerful yet flexible debuggers are indispensable for the efficient programming of complex distributed synchronous and asynchronous algorithms on loosely coupled parallel processors. Traditional debugging systems, including POKER, permit a user to start, stop, and single-step a parallel program executing on a parallel processor while observing the successive changes of the traced variables and labels. These debuggers are limited in that the user must specify the list of variables and labels to be traced through the declaration section of each routine. As a result, the user may not alter the contents of this set once program execution has been initiated. More recently, debuggers such as ndb and dbxtool claim dynamic debugging support but are limited by clumsy user interfaces. While ndb works within a single window and requires the user to type commands, dbxtool is a simple collection of uniprocessor debuggers with no explicit coordination. PROVIDE claims to use graphical tools for debugging but is limited to a simplified programming language. Furthermore, both ndb and dbxtool are proprietary; few details, if any, on their software engineering design are available in the literature. This article details the software engineering issues in the design and implementation of an actual distributed dynamic runtime software debugger, Ddbx-LPP, that permits the user to view any global variable, structure, and parameter during program execution at any node of a parallel processor system. The system is exclusively mouse driven for relatively easy debugging. The user may insert breakpoints corresponding to any source code line, either before initiating execution or when program execution is temporarily suspended at a breakpoint. Furthermore, when the program, in the course of execution, experiences a nonrecoverable error, its execution is temporarily suspended and control is transferred to the user in a manner identical to the case of a deliberately inserted breakpoint. Although further execution is prohibited, Ddbx-LPP permits the user to view variables and structures to determine the cause of the error. Ddbx-LPP's unique ability may be credited to its significant analysis of the object code and symbol table, generated as a result of compilation under the “-g” option, both before and during the actual execution of the program. In contrast to POKER, which requires a sequential programming environment, Ddbx-LPP may function with a user program written in C for any loosely coupled parallel processor. Ddbx-LPP is superior to user-inserted “printf” statements to print out the values of variables and structures during execution because 1. 1) to print all variables and structures would require an overwhelming number of printf statements, and 2. 2) to insert new printf statements would mean program recompilation. Ddbx-LPP has been implemented on the ARMSTRONG system at Brown University and is equally applicable to any loosely coupled parallel processor system.
Lambert‐Eaton Myasthenic Syndrome

A high index of suspicion is essential in arriving at the correct diagnosis of Lambert-Eaton myasthenic syndrome (LEMS). LEMS should be considered in the differential in any patient who has proximal weakness, reduced or absent muscle stretch reflexes, and dry mouth. Weakness predominates in hip and shoulder muscles, but may also affect ocular and oropharyngeal muscles to a lesser extent. The diagnosis is confirmed by demonstrating characteristic electromyographic findings-low-amplitude muscle responses that increase dramatically after activation. Most patients also have circulating antibodies to the voltage-gated calcium channel. Half the patients with LEMS have a malignancy, usually small-cell lung cancer. The diagnosis should trigger an intensive search for malignancy, especially in older patients with a history of smoking. Younger, nonsmoking patients are likely to have LEMS as part of a more general autoimmune state. Successful treatment of the underlying cancer leads to improvement in many patients. More than 85% of patients have clinically significant benefit from 3,4-diaminopyridine (DAP). In over half of these, the improvement is marked. If severe weakness persists despite DAP, immunotherapy should be considered. Plasma exchange and high-dose immunoglobulin induce transient improvement in many patients, but function rarely becomes normal. Combinations of prednisone, azathioprine, or cyclosporine have been used with variable success. Improvement, if any, occurs only after many months and requires chronic administration of immunosuppressive medications at significant doses. The long-term prognosis in LEMS is determined by the presence of cancer or other autoimmune disease.
Peaks and Troughs in Helioseismology: The Power Spectrum of Solar Oscillations

I present a matched-wave asymptotic analysis of the driving of solar oscillations by a general localized source. The analysis provides a simple mathematical description of the asymmetric peaks in the power spectrum in terms of the relative locations of eigenmodes and troughs in the spectral response. It is suggested that the difference in measured phase function between the modes and the troughs in the spectrum will provide a key diagnostic of the source of the oscillations. I also suggest a form for the asymmetric line profiles to be used in the fitting of solar power spectra. Finally, I present a comparison between the numerical and asymptotic descriptions of the oscillations. The numerical results bear out the qualitative features suggested by the asymptotic analysis but suggest that numerical calculations of the locations of the troughs will be necessary for a quantitative comparison with the observations.
Flat metrics, cubic differentials and limits of projective holonomies

F. Labourie and the author independently have shown that a convex real projective structure on an oriented closed surface S of genus at least two is equivalent to a pair of a conformal structure plus a holomorphic cubic differential. Along certain paths, we find the limiting holonomy of convex real projective structures on a surface S corresponding corresponding to a given fixed conformal structure S and a holomorphic cubic differential λ U0 as \(\lambda\to\infty\) . We explicitly give part of the data needed to identify the boundary point in Inkang Kim’s compactification of the deformation space of convex real projective structures. The proof follows similar analysis to that studied by Mike Wolf is his application of harmonic map theory to reproduce Thurston’s boundary of Teichmuller space.
The secrecy capacity of practical quantum cryptography

Quantum cryptography has attracted much recent attention due to its potential for providing secret communications that cannot be decrypted by any amount of computational effort. This is the first analysis of the secrecy of a practical implementation of the BB84 protocol that simultaneously takes into account and presents the full set of analytical expressions for effects due to the presence of pulses containing multiple photons in the attenuated output of the laser, the finite length of individual blocks of key material, losses due to error correction, privacy amplification, and authentication, errors in polarization detection, the efficiency of the detectors, and attenuation processes in the transmission medium. The analysis addresses eavesdropping attacks on individual photons rather than collective attacks in general. Of particular importance is the first derivation of the necessary and sufficient amount of privacy amplification compression to ensure secrecy against the loss of key material which occurs when an eavesdropper makes optimized individual attacks on pulses containing multiple photons. It is shown that only a fraction of the information in the multiple photon pulses is actually lost to the eavesdropper.
Preparation and diastereo- and enantioselective trifluorocrotylboration with (Z)-(B)-diisopinocampheyl(4,4,4-trifluorobut-2-en-1-yl)borane

Contrary to the non-fluorinated analogs, the hydroboration of trifluoromethylallene with diisopinocampheylborane provides the corresponding Z-trifluorocrotylborane reagent. Trifluorocrotylboration of a series of aldehydes with this reagent provides the corresponding syn-β-trifluoromethyl homoallyl alcohols in high diastereo- and enantioselectivities.
Spincasting Of A 3.5-m Diameter f/1.75 Mirror Blank In Borosilicate Glass

A 3.5-meter-diameter telescope primary-mirror blank was cast from E6 borosilicate glass at the University of Arizona, Steward Observatory Mirror Lab. A light-weighted-hollow design was made with a faceplate and backplate separated by a middle volule of ribs in a honeycomb pattern. The curvature of the F/1.75-mirror face was formed by spinning the melted glass at 8.54 RPM. A telescope on Apache Point in New Mexico will use this mirror.
Sonographic Imaging of Cervical Lymph Nodes in Patients with Thyroid Cancer

Sonography plays an important role in the evaluation of patients who have thyroid carcinoma by identifying metastatic disease to the regional cervical lymph nodes. The sonographic appearance of lymph node metastases may vary from subtle alterations in echogenicity or vascular patterns to more obvious findings of calcifications and cystic changes within an affected node. Identification of metastatic disease to lateral cervical lymph nodes by sonography may affect the extent of surgical resection at the time of diagnosis. In patients who have had thyroidectomy for cancer, sonographic evaluation has proved to be the most sensitive imaging technique to detect thyroid cancer recurrence in the neck.
Experimental Investigation of Isolated and Simultaneous Internal Resonances in Suspended Cables

The near resonant response of suspended elastic cables driven by harmonic, planar excitation is investigated experimentally. Measurements of large amplitude cable motions confirm previous theoretical predictions of fundamental classes of internally-resonant responses. For particular magnitudes of equilibrium curvature, strong modal interactions arise through isolated (two-mode) or simultaneous (three-mode) internal resonances. Four qualitatively different periodic responses are observed : (1) pure planar response, (2) 2 :1 internally resonant nonplanar response, (3) 1 :1 internally resonant nonplanar response, and (4) simultaneous, 2 :2 :1 internally resonant nonplanar response. Quasiperiodic responses are also observed.
Geodisterol, a novel polyoxygenated sterol with an aromatic A ring from the tropical marine sponge Geodia sp.

Abstract Geodisterol ( 1 ), the first marine polyoxygenated sterol with an aromatic A ring, was isolated from the Indo-Pacific sponge Geodia sp. The structural and stereochemical features of 1 were based on the extensive analysis of 1D and 2D of it and MPA esters 2 and 3 .
Calcareous paleosols in the Triassic Dolores Formation, southwestern Colorado

Calcareous paleosols are common in the upper member of the Upper Triassic Dolores Formation in the San Juan Mountains of southwestern Colorado. These soils are best developed in the upper portion of 2 to 10m-thick beds of very fine sandstone to coarse siltstone. The sandstone/siltstone beds represent sand sheet facies deposited by eolian and aqueous processes on the margins of a large Triassic erg. Textures and structures associated with these paleosols include individual and stacked micrite and microspar nodules, downward-branching purple and green mottle in reddish brown parent rock, irregular polygonal fractures filled with sparry calcite or red mudstone, 3 to 15mm-diameter tubular meniscate burrows (striotubules of the trace fossils Scoyenia, Ancorichnus, and Muensteria), and hematite-pigmented skelsepic fabric. Cross-cutting and replacement relationships between burrows and carbonate nodules indicate that bioturbation and glaebule development were penecontemporaneous. Classification of these soils using the USDA or FAO/UNESCO systems is complicated by burial diagenesis. Clay accumulation has probably occurred both by pedogenic illuviation and intrastratal solution. The development of a calcic horizon in a loam in tropical paleolatitudes prior to the evolution of grasses constrains the classification of these soils. Possibilities include assignment of these paleosols to ustropepts, xerochrepts, or orthids, and locally tomore » ustalfs or argids.« less
Vertical distribution of number concentration and size distribution of atmospheric aerosols over the central United States

Aircraft measurements of trace gases and atmospheric aerosols were performed over the central United States during four research field periods in 1988 as a part of the Central U.S. RADM Test and Assessment Intensives (CURTAIN). Aerosol size distributions were measured at six altitudes between 700 and 3200 m above sea level over the size range 0.1-32 micrometers, using two Particle Measuring Systems (PMS) probes; an active scattering aerosol spectrometer probe (ASASP) and a forward scattering spectrometer probe (FSSP), mounted on the wings of the NOAA King Air research aircraft. The FSSP data were first corrected using a scheme which accounts for the effects of the probe's electronic response time and nonuniformity in the laser beam intensity profile on the measured aerosol size spectra. Vertical profiles of the average aerosol concentration show seasonal characteristics, with maximum concentrations during summer and minimum concentrations during winter. In summer, the aerosol number concentration in the fme. particle mode is rather constant about 2,000 cm-3 up to about 1900 m asl level. Number concentration of the soil. derived aerosols in the coarse-particle mode is maximized during spring. The measured aerosol number size distributions exhibit typically bimodal distributions for both boundary layer and free tropospheric aerosols. Each measured number size distribution is approximated with a sum of two lognormal distributions using a lognormal fitting routine. The aerosol size distribution data measured in the boundary layer and in the free troposphere are compared with the LOWTRAN 'Rural' aerosol model and Tropospheric aerosol model, respectively.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
First passage in infinite paraboloidal domains

We study first-passage properties for a particle that diffuses either inside or outside of generalized paraboloids, defined by where p > 1, with absorbing boundaries. When the particle is inside the paraboloid, the survival probability S(t) generically decays as a stretched exponential, lnS ~ − t(p − 1)/(p + 1), independent of the spatial dimension. For a particle outside the paraboloid, the dimensionality governs the asymptotic decay, while the exponent p specifying the paraboloid is irrelevant. In two and three dimensions, S ~ t − 1/4 and S ~ (lnt) − 1, respectively, while in higher dimensions the particle survives with a finite probability. We also investigate the situation where the interior of a paraboloid is uniformly filled with non-interacting diffusing particles and estimate the distance between the closest surviving particle and the apex of the paraboloid.
Skin-surface warming: Heat flux and central temperature

Abstract The authors determined the efficacy of four postoperative warming devices by measuring cutaneous and tympanic membrane temperatures, and heat loss/gain using 11 thermocouples and ten thermal flux transducers in five healthy, unanesthetized volunteers. Overall thermal comfort was evaluated at 5–10 min intervals using a 10-cm visual analog scale. The warming devices were: 1) a pair of 250-W infrared heating lamps mounted 71 cm above the abdomen; 2) the Thermal Ceiling MTC XI UL (500 W) set on "high" and mounted 56 cm above the volunteer; 3) a 54-by-145 cm circulating-water blanket set to 40°C placed over the volunteer; and 4) the Bair-Hugger forced air warmer with an adult-sized cover set on "low" (≈33° C), "medium" (≈38° C), and "high" (≈43° C). Following a 10-min control period, each device was placed over the volunteer and activated for a 30-min period. All devices were started "cold" and warmed up during the study period. The Bair Hugger set on "medium" decreased heat loss more than each radiant warming device and as much as the circulating-water blanket. All methods reached maximum efficacy within 20 min. Set on "high," the Bair Hugger increased skin-surface temperature more than the circulating-water blanket. The Bair Hugger (all settings) and the water blanket raised skin temperature more than the radiant heaters. The circulating-water blanket was the most effective device for heating an optimally placed transducer on the chest (directly under and parallel to the radiant heat sources, and touching the water and Bair Hugger blankets). However, when the entire skin surface was considered, the Bair Hugger set on "high" transferred the most heat, enough to increase mean body temperature ≈1.5 degrees C/h in a postoperative patient without thermoregulatory responses. Central temperature decreased slightly (the expected thermoregulatory response) during skin-surface warming, the decrease being roughly in proportion to the efficacy of the warming devices. Cutaneous heat flux correlated well with the skin-surface temperature, but not with thermal comfort. There was no correlation between forehead and tympanic membrane temperatures.
Oxidative bisdecarboxylation of α-alkoxymalonic acids with cerium(IV)

Abstract Ceric ammonium nitrate is an excellent reagent for preparing carboxylic esters from α-alkoxymalonic acids by oxidative bisdecarboxylation.
Opportunities, challenges, and fantasies in lattice QCD

Abstract Some important problems in quantitative QCD will certainly yield to hard work and adequate investment of resources, others appear difficult but may be accessible, and still others will require essentially new ideas. Here I identify several examples in each class.