cssi/SciSciGPT-SciSciNet huggingface dataset:
The biology of breast tumor progression. Acquisition of hormone independence and resistance to cytotoxic drugs.

Many breast tumors appear to follow a predictable clinical pattern, being initially responsive to endocrine therapy and to cytotoxic chemotherapy but ultimately exhibiting a phenotype resistant to both modalities. Using the MCF-7 human breast cancer cell line as an example of an ‘early’ phenotype (estrogen and progesterone receptor positive, steroid responsive, low metastatic potential), we have isolated and characterized a series of hormone-independent but hormone-responsive variants (MI11 and MCM/LCCl). However, these variants remain responsive to both antiestrogens and cytotoxic drugs (methotrexate and colchicine). MIII and MCF7/LCC1 cells appear to mimic some of the critical aspects of the early progression to a more aggressive phenotype. An examination of the phenotype of these cells suggests that some hormone-independent breast cancer cells are derived from hormone-dependent parental cells. The development of a hormone-independent phenotype can arise independently of acquisition of a cytotoxic drug ...
Finite element nonlinear panel flutter with arbitrary temperatures in supersonic flow

A finite element frequency domain method for predicting nonlinear flutter response of panels with temperature effects is presented. By using the principle of virtual work, the element nonlinear stiffness formulation for a panel under a combined thermal and aerodynamic loads is derived on the bases of von Karman's large deflection plate theory, the first-order piston theory aerodynamics and the quasi-steady thermal stress theory. The system equations of motion can be mathematically separated into two sets of equations and then solved in sequence. The first set of equations yields the panel thermal-aerodynamic equilibrium and the second set of equations of motion leads to the flutter limit-cycle oscillations. Stability and flutter boundaries can also be obtained from the two sets of system equations. Finite element large amplitude limit-cycle flutter results at different uniform temperatures are obtained for a simply supported square panel and are compared with existing Galerkin/time integration and other finite element solutions. Effects of nonuniform temperature distributions, panel length-to-width ratios, and boundary conditions on flutter responses of rectangular and triangular panels are presented.
A SEARCH FOR STAR-DISK INTERACTION AMONG THE STRONGEST X-RAY FLARING STARS IN THE ORION NEBULA CLUSTER

The Chandra Orion Ultradeep Project observed hundreds of young, low-mass stars undergoing highly energetic X-ray flare events. The 32 most powerful cases have been previously modeled with the result that the magnetic structures responsible for these flares can be many stellar radii in extent. In this paper, we model the observed spectral energy distributions (SEDs) of these 32 stars in order to determine, in detail for each star, whether there is circumstellar disk material situated in sufficient proximity to the stellar surface for interaction with the large magnetic loops inferred from the observed X-ray flares. Our SEDs span the wavelength range 0.3-8 μm (plus 24 μm for some stars), allowing us to constrain the presence of dusty circumstellar material out to 10 AU from the stellar surface in most cases. For 24 of the 32 stars in our sample the available data are sufficient to constrain the location of the inner edge of the dusty disks. Six of these (25%) have SEDs consistent with inner disks within reach of the observed magnetic loops. Another four stars may have gas disks interior to the dust disk and extending within reach of the magnetic loops, but we cannot confirm this with the available data. The remaining 14 stars (58%) appear to have no significant disk material within reach of the large flaring loops. Thus, up to ~40% of the sample stars exhibit energetic X-ray flares that possibly arise from a magnetic star-disk interaction, and the remainder are evidently associated with extremely large, free-standing magnetic loops anchored only to the stellar surface.
A general perspective of extreme events in weather and climate

One of the most important problems in meteorology, physical oceanography, climatology, and related fields is the understanding and dynamical description of multi-scale interactions. Multi-scale interactions are closely related to extreme events in climate and, therefore, of great practical importance. Here an extreme event is defined in terms of the non-Gaussian tail (sometimes also called a weather or climate regime) of the data's probability density function (PDF), as opposed to the definition in extreme value theory, where the statistics of time series maxima (and minima) in a given time interval are studied. The non-Gaussian approach used here allows for a dynamical view of extreme events in weather and climate, going beyond the solely mathematical arguments of extreme value theory. Extreme events are by definition scarce, but they can have a significant impact on people and countries in the affected regions. Understanding extremes has become an important objective in weather/climate variability research because weather and climate risk assessment depends on knowing the tails of PDFs. In recent years, new tools that make use of advanced stochastic theory have evolved to evaluate extreme events and the physics that govern these events. Stochastic methods are ideal to study multi-scale interactions and extreme events because they link vastly different time and spatial scales. One theory attributes extreme anomalies to stochastically forced dynamics, where, to model nonlinear interactions, the strength of the stochastic forcing depends on the flow itself (multiplicative noise). This closure assumption follows naturally from the general form of the equations of motion. Because stochastic theory makes clear and testable predictions about non-Gaussian variability, the multiplicative noise hypothesis can be verified by analyzing the detailed non-Gaussian statistics of atmospheric and oceanic variability. This review paper discusses the theoretical framework, observational evidence, and related developments in stochastic modeling of extreme events in weather and climate.
Performance effects of failure to make Adequate Yearly Progress (AYP): Evidence from a regression discontinuity framework

Abstract As the No Child Left Behind (NCLB) law moves through the reauthorization process, it is important to understand the basic performance impacts of its central structure of accountability. In this paper, I examine the effects of failure to make Adequate Yearly Progress (AYP) under NCLB on subsequent student math and reading performance at the school level. Using panel data on Maryland elementary and middle schools from 2003 to 2009, I find that the scope of failure matters: Academic performance suffers in the short run in response to school-wide failure. However, schools that meet achievement targets for the aggregate student group, yet fail to meet at least one demographic subgroup's target see between 3 and 6 percent more students in the failing subgroup score proficiently the following year, compared to if no accountability pressure were in place. I discuss alternative interpretations and policy implications of the main findings.
Quantum linear magnetoresistance

A description is presented of experimental results, old and new ones, in which a magnetoresistance was discovered, linear in magnetic field. It is explained that there are two theoretical possibilities for such a phenomenon. The first one happens in a polycrystalline metal in a classically large field; it was known since the late 1950s. The other one is the so-called quantum magnetoresistance in semimetals and in some single crystalline metals having small pockets of the Fermi surface with a small effective mass.
Integral homology of loop groups via Langlands dual groups

Let K be a connected compact Lie group, and G its complexification. The homology of the based loop group ΩK with integer coefficients is naturally a Z-Hopf algebra. After possibly inverting 2 or 3, we identify H∗(ΩK, Z) with the Hopf algebra of algebraic functions on B∨ e , where B^∨ is a Borel subgroup of the Langlands dual group scheme G^∨ of G and B^∨ e is the centralizer in B^∨ of a regular nilpotent element e ∈ LieB^∨. We also give a similar interpretation for the equivariant homology of ΩK under the maximal torus action.
New Analytical Results on Anisotropic Membranes

Abstract We report on recent progress in understanding the tubular phase of self-avoiding anisotropic membranes. After an introduction to the problem, we sketch the renormalization group arguments and symmetry considerations that lead us to the most plausible fixed point structure of the model. We then employ an ϵ-expansion about the upper critical dimension to extrapolate to the physical interesting 3-dimensional case. The results are ν = 0.62 for the Flory exponent and ζ = 0.80 for the roughness exponent. Finally we comment on the importance that numerical tests may have to test these predictions.
Self: The power of simplicity

Self is a new object-oriented language for exploratory programming based on a small number of simple and concrete ideas: prototypes, slots, and behavior. Prototypes combine inheritance and instantiation to provide a framework that is simpler and more flexible than most object-oriented languages. Slots unite variables and procedures into a single construct. This permits the inheritance hierarchy to take over the function of lexical scoping in conventional languages. Finally, because Self does not distinguish state from behavior, it narrows the gaps between ordinary objects, procedures, and closures. Self's simplicity and expressiveness offer new insights into object-oriented computation.
Performance characteristics of a 1.8 by 3.7 meter Fresnel lens solar concentrator

Line-focusing acrylic Fresnel lenses with application potential in the 200 to 370 C range were analytically and experimentally investigated. The measured solar concentration characteristics of a 1.8 by 3.7 m lens and its utilization in a solar collection mode are presented. A measured peak concentration ratio of 62 with 90 percent of the transmitted energy focused into a 5.0cm width was achieved. A peak concentration of 59 and a 90 percent target width of 4.3 cm were analytically computed. The experimental and analytical lens transmittance was 78 percent and 86 percent, respectively. The lens was also interfaced with a nonevacuated receiver assembly and operated in the collection mode. With a natural oxide absorber tube coating (alpha/epsilon = 0.79/0.10), the measured collection efficiency ranged from 43 percent to 200 C to 34 percent at 260 C. Efficiency improvements to the 40 to 50 percent range can be achieved with second generation lenses and higher performance absorptive coatings.
The role of ERISA preemption in health reform: Opportunities and limits

The Employee Retirement Income Security Act (ERISA) is a federal law regulating the administration of private employer-sponsored benefits including health benefits (i.e., health insurance offered by an employer). In general, since the federal government has exercised its authority to preempt state regulation of the administration of private employer-sponsored health plans, states are blocked from enforcing laws interfering with ERISA. As many states pursue health care reform experiments, ERISA preemption becomes relevant as a potential limit on the scope and type of reforms states are able to enact. The dominant trend in ERISA litigation has been to preempt state legislation and litigation interfering with the administration of private employer-sponsored health plans, making large-scale state health care reform initiatives difficult. The purpose of this paper is to examine the trajectory of judicial interpretation of ERISA and to discuss what opportunities exist to facilitate health care initiatives given the constraints of ERISA preemption.
Electrospun polyurethane fibers for absorption of volatile organic compounds from air.

Electrospun polyurethane fibers for removal of volatile organic compounds (VOC) from air with rapid VOC absorption and desorption have been developed. Polyurethanes based on 4,4-methylenebis(phenylisocyanate) (MDI) and aliphatic isophorone diisocyanate as the hard segments and butanediol and tetramethylene glycol as the soft segments were electrospun from their solutions in N,N-dimethylformamide to form micrometer-sized fibers. Although activated carbon possessed a many-fold higher surface area than the polyurethane fiber meshes, the sorption capacity of the polyurethane fibers was found to be similar to that of activated carbon specifically designed for vapor adsorption. Furthermore, in contrast to VOC sorption on activated carbon, where complete regeneration of the adsorbent was not possible, the polyurethane fibers demonstrated a completely reversible absorption and desorption, with desorption obtained by a simple purging with nitrogen at room temperature. The fibers possessed a high affinity toward to...
Discussion of “Multiple Testing for Exploratory Research” by J. J. Goeman and A. Solari

Goeman and Solari [Statist. Sci. 26 (2011) 584–597] have addressed the interesting topic of multiple testing for exploratory research, and provided us with nice suggestions for exploratory analysis. They defined properties that an inferential procedure should have for exploratory analysis: the procedure should be mild, flexible and post hoc. Their inferential procedure gives a lower bound on the number of false hypotheses among the selected hypotheses, and moreover whenever possible identifies elementary hypotheses that are false. The need to estimate a lower bound on the number of false hypotheses arises in various applications, and the partial conjunction approach was developed for this purpose in Biometrics 64 (2008) 1215–1222 (see also Philos. Trans. R. Soc. Lond. Ser. A 367 (2009) 4255–4271 for more details). For example, in a combined analysis of several studies that examine the same problem, it is of interest to give a lower bound on the number of studies in which the finding was reproduced. I will first address the relation between the method of Goeman and Solari and the partial conjunction approach. Then I will discuss possible extensions and address the issue of exploration in more general settings, where the local test may not be defined in advance or where the candidate hypotheses may not be known to begin with.
Nanosized Iron- or Copper-Catalyzed Homocoupling of Aryl, Heteroaryl, Benzyl, and Alkenyl Grignard Reagents

Abstract Under very mild reaction conditions, iron or copper nanoparticles efficiently promoted the homocoupling of different Grignard reagents in tetrahydrofuran at room temperature. The nanosized iron or copper particles were generated in situ in a simple and economical way from commercially available FeCl2 or CuCl2, respectively, an excess of lithium powder, and a catalytic amount (5 mol%) of 4,4′-di-tert-butylbiphenyl (DTBB) as electron carrier. The reaction of a series of aryl, heteroaryl, benzyl, and alkenyl Grignard reagents in the presence of a substoichiometric amount of the iron or copper nanoparticles led to the formation of the corresponding homocoupling products in good yield.
Spatio-temporal data reduction with deterministic error bounds

A common way of storing spatio-temporal information about mobile devices is in the form of a 3D (2D geography + time) trajectory. We argue that when cellular phones and Personal Digital Assistants become location-aware, the size of the spatio-temporal information generated may prohibit efficient processing. We propose to adopt a technique studied in computer graphics, namely line-simplification, as an approximation technique to solve this problem. Line simplification will reduce the size of the trajectories. Line simplification uses a distance function in producing the trajectory approximation. We postulate the desiderata for such a distance-function: it should be sound, namely the error of the answers to spatio-temporal queries must be bounded. We analyze several distance functions, and prove that some are sound in this sense for some types of queries, while others are not. A distance function that is sound for all common spatio-temporal query types is introduced and analyzed. Then we propose an aging mechanism which gradually shrinks the size of the trajectories as time progresses. We also propose to adopt existing linguistic constructs to manage the uncertainty introduced by the trajectory approximation. Finally, we analyze experimentally the effectiveness of line-simplification in reducing the size of a trajectories database.
Neon and Oxygen Abundances in M33

We present new spectroscopic observations of 13 H II regions in the Local Group spiral galaxy M33. The regions observed range from 1 to 7 kpc in distance from the nucleus. Of the 13 H II regions observed, the [O III] λ4363 line was detected in six regions. Electron temperatures were thus able to be determined directly from the spectra using the [O III] λλ4959, 5007/λ4363 line ratio. Based on these temperature measurements, oxygen and neon abundances and their radial gradients were calculated. For neon, a gradient of -0.016 ± 0.017 dex kpc-1 was computed, which agrees with the Ne/H gradient derived previously from ISO spectra. A gradient of -0.012 ± 0.011 dex kpc-1 was computed for O/H, much shallower than was derived in previous studies. The newly calculated O/H and Ne/H gradients are in much better agreement with each other, as expected from predictions of stellar nucleosynthesis. We examine the correlation between the WC/WN ratio and metallicity, and find that the new M33 abundances do not impact the observed correlation significantly. We also identify two new He II-emitting H II regions in M33, the first to be discovered in a spiral galaxy other than the Milky Way. In both cases the nebular He II emission is not associated with Wolf-Rayet stars. Therefore, caution is warranted in interpreting the relationship between nebular He II emission and Wolf-Rayet stars when both are observed in the integrated spectrum of an H II region.
Automatic Differentiation in Robust Optimization

In this study the use of automatic differentiation techniques significantly reduces the number of analysis calls and the CPU time required for robust optimum design. Traditionally, robust optimum design procedures have relied on finite differencing techniques to evaluate sensitivities for use in gradient-based optimization. Robust objective functions and robust constraints are typically formulated as compound functions that invoke the original objective or constraint many times for each robust evaluation. In this research, automatic differentiation techniques are used to avoid the costly finite differencing of robust objective functions and robust constraints. Sensitivities calculated using automatic differentiation are exact and therefore enhance performance. Two new robust optimization extensions are developed to evaluate the utility of using automatic differentiation in robust optimization. One is a sensitivity-based procedure, and the other makes use of experimental design techniques. These two new robust optimization extensions are successfully implemented in application to an aircraft concept sizing test problem.
Transfinite diameter and the resultant

We prove a formula for the Fekete-Leja transfinite diameter of the pullback of a set E in C^N by a regular polynomial map F, expressing it in terms of the resultant of the leading part of F and the transfinite diameter of E. We also establish the nonarchimedean analogue of this formula. A key step in the proof is a formula for the transfinite diameter of the filled Julia set of F.
Photoreactions of tetrafluorodiphosphine with alkynes

Abstract The reactions of tetrafluoridiphosphine with several alkynes in the gas phase and under UV irradiation were studied. Simple addition products were obtained in substantial yield from CF 3 CCH, CF 3 CCCH 3 , and CF 3 CCCF 3 . Methyl substituted alkynes gave little volatile product while ethyne and diphenyl ethyne gave no volatile addition products. Non-volatile byproducts were obtained, probably polymers, in substantial quantity in the latter instances. Volatile products were characterized by IR and NMR spectra and by mass spectrometry.
Fire containment in grids of dimension three and higher

We consider a deterministic discrete-time model of fire spread introduced by Hartnell [Firefighter! an application of domination, Presentation, in: 20th Conference on Numerical Mathematics and Computing, University of Manitoba in Winnipeg, Canada, September 1995] and the problem of minimizing the number of burnt vertices when a fixed number of vertices can be defended by firefighters per time step. While only two firefighters per time step are needed in the two-dimensional lattice to contain any outbreak, we prove a conjecture of Wang and Moeller [Fire control on graphs, J. Combin. Math. Combin. Comput. 41 (2002) 19-34] that 2d-1 firefighters per time step are needed to contain a fire outbreak starting at a single vertex in the d-dimensional square lattice for d>=3; we also prove that in the d-dimensional lattice, d>=3, for each positive integer f there is some outbreak of fire such that f firefighters per time step are insufficient to contain the outbreak. We prove another conjecture of Wang and Moeller that the proportion of elements in the three-dimensional grid P"nxP"nxP"n which can be saved with one firefighter per time step when an outbreak starts at one vertex goes to 0 as n gets large. Finally, we use integer programming to prove results about the minimum number of time steps needed and minimum number of burnt vertices when containing a fire outbreak in the two-dimensional square lattice with two firefighters per time step.
Measuring the redshift of reionization with a modest array of low-frequency dipoles

The designs of the first generation of cosmological 21-cm observatories are split between single dipole experiments which integrate over a large patch of sky in order to find the global (spectral) signature of reionization, and interferometers with arcminute-scale angular resolution whose goal is to measure the 3D power spectrum of ionized regions during reionization. We examine whether intermediate scale instruments with complete Fourier (uv) coverage are capable of placing new constraints on reionization. We find that even without using a full power spectrum analysis, the global redshift of reionization, zreion, can in principle be measured from the variance in the 21-cm signal among multiple beams as a function of frequency at a roughly 1 degree angular scale. At this scale, the beam-to-beam variance in the differential brightness temperature peaks when the average neutral fraction was ~ 50%, providing a convenient flag of zreion. We choose a low angular resolution of order 1° to exploit the physical size of the ionized regions and maximize the signal-to-noise ratio. Thermal noise, foregrounds, and instrumental effects should also be manageable at this angular scale, as long as the uv coverage is complete within the compact core required for low-resolution imaging. For example, we find that zreion can potentially be detected to within a redshift uncertainty of Δzreion1 in 500 hours of integration on the existing MWA prototype (with only 32 × 16 dipoles), operating at an angular resolution of ~ 1° and a spectral resolution of 2.4 MHz.
An analytical approach to star identification reliability

Abstract The problem of real-time, on-board star pattern identification is considered which must precede any spacecraft attitude estimation algorithm based on measured line of sight directions to stars. Following the use of the search-less k -vector method to access feasible candidate stars (detailed in a previous paper) a tiered logical structure is introduced in which inter-star angles for pairs, triples and general elementary star configurations are used to match measured patterns to corresponding patterns in a star catalog. Analytical expressions are developed for the expected frequency of matching an observed star pattern with an incorrect pattern in the star catalog due to measurement error. Such knowledge of erroneous match frequencies can be used to rigorously terminate the star identification process with a virtually certain match, while obviating the need for expensive Monte Carlo simulations. Developments shown are supported with a few simulation results.
Chondrites as samples of differentiated planetesimals

Abstract Chondritic meteorites are unmelted and variably metamorphosed aggregates of the earliest solids of the solar system. The variety of metamorphic textures in chondrites motivated the “onion shell” model in which chondrites originated at varying depths within a parent body heated primarily by the short-lived radioisotope 26 Al, with the highest metamorphic grade originating nearest the center. Allende and a few other chondrites possess a unidirectional magnetization that can be best explained by a core dynamo on their parent body, indicating internal melting and differentiation. Here we show that a parent body that accreted to >~200 km in radius by ~ 1.5 Ma after the formation of calcium–aluminum-rich inclusions (CAIs) would have a differentiated interior, and ongoing accretion would add a solid undifferentiated crust overlying a differentiated interior, consistent with formational and evolutionary constraints inferred for the CV parent body. This body could have produced a magnetic field lasting more than 10 Ma. This hypothesis represents a new model for the origin of some chondrites, presenting them as the unprocessed crusts of internally differentiated early planetesimals. Such bodies may exist in the asteroid belt today; the shapes and masses of the two largest asteroids, 1 Ceres and 2 Pallas, can be consistent with differentiated interiors, conceivably with small iron cores with hydrated silicate or ice–silicate mantles, covered with undifferentiated crusts.
A Monte Carlo simulation study of the mechanical and conformational properties of networks of helical polymers. I. General concepts

Abstract We study the mechanical and conformational properties of networks of helical polymers with a combination of Monte Carlo simulations based on the Wang–Landau algorithm and the three-chain model. We find that the stress–strain behavior of these networks has novel features not observed in typical networks made of synthetic polymers. In particular, we find that as these networks are stretched they first strengthen, then soften and finally strengthen again. This non-monotonic behavior of the stress correlates with the one of the helical content and is rationalized by the elongation-induced formation and melting of the helical structure of the polymer. We complement these results with a study of other conformational properties of the polymer strands that clarify the molecular mechanisms behind the mechanical behavior of these networks. Finally, we present a qualitative comparison of some of our results with the theoretical ones recently reported by Kutter and Terentjev.
Pyrosequencing: A Simple Method for Accurate Genotyping

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a tremendous amount of data available comes an explosion of genotyping methods. Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. It also has the ability to identify tri-allelic, indels, short-repeat polymorphisms, along with determining allele percentages for methylation or pooled sample assessment. In addition, there is a standardized control sequence that provides internal quality control. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.
Synthesis of Acyclic α,β-Unsaturated Ketones via Pd(II)-Catalyzed Intermolecular Reaction of Alkynamides and Alkenes

We report an intermolecular oxidative coupling of alkynamides and terminal alkenes to synthesize E-α,β-unsaturated ketones under very mild conditions using catalytic Pd(II) and an oxidant. An 17O isotope labeling experiment implicates a cyclic oxypalladation intermediate in this reaction.
Altered binding of serum thyroid hormone to thyroxine-binding globulin in women with functional hypothalamic amenorrhea

Abstract Objective: To further characterize hypothyroidemia with decreased serum concentrations of total triiodothyronine and total T 4 in women with functional hypothalamic amenorrhea. Design: Cohort study. Setting: University of California San Diego Clinical Research Center. Patient(s): 8 women with functional hypothalamic amenorrhea (hypogonadotropic or normogonadotropic amenorrhea of at least 6 months duration) and 9 normal cycling women in the early follicular phase of their cycles. Intervention(s): 24-hour frequent blood sampling. Main Outcome Measure(s): Comparison of levels of thyroid hormones and binding proteins between functional hypothalamic amenorrhea and normal cycling women. Measurements of serum free T 4 , free triiodothyronine, total T 4 , total triiodothyronine, reverse triiodothyronine, thyroid-binding globulin, albumin, and prealbumin levels and determination of T 4 binding and binding affinity to each of the three binding proteins. Result(s): The results confirmed reduced levels of total triiodothyronine and total T 4 , but revealed no significant difference in free triiodothyronine and free T 4 , as well as reverse triiodothyronine, levels between functional hypothalamic amenorrhea and normal cycling women. Although serum levels of thyroid hormone-binding proteins were similar between normal cycling women and functional hypothalamic amenorrhea, a significant decrease in T 4 bound to thyroid binding globulin along with a decrease in apparent affinity of thyroid-binding globulin for T 4 was present in functional hypothalamic amenorrhea. No differences in prealbumin-or albumin-T 4 interactions were found. Conclusion(s): In functional hypothalamic amenorrhea, a reduced thyroid-binding globulin binding affinity appears to explain the disparity between normal levels of free triiodothyronine, free T 4 , and binding proteins in the face of reduced levels of total triiodothyronine and total T 4 .
Butorphanol compared with fentanyl in general anaesthesia for ambulatory laparoscopy

Butorphanol was compared with fentanyl as the narcotic component of general anaesthesia for ambulatory laparoscopic surgery. This double-blind, randomized study enrolled 60 healthy women who received equianalgesic doses of fentanyl 1 microgram.kg-1 (F, n = 30) or butorphanol 20 micrograms.kg-1 (B, n = 30) prior to induction of anaesthesia. Tracheal anaesthesia was maintained with nitrous oxide/oxygen, isoflurane, and succinylcholine by infusion. Intraoperatively, patients who received B demonstrated lower pulse rate before and after intubation (P less than 0.05, P less than 0.01) and lower diastolic blood pressure after intubation (P less than 0.01). Anesthesiologists judged the maintenance phase as satisfactory more often with B (P less than 0.05). Postoperatively, there were no differences in analgesic need. No major side-effects occurred in either group. Among minor side-effects, patients who received B reported postoperative sedation more often, 77% vs 37% (P less than 0.01), which occurred during the first 45 min of recovery (P less than 0.05). Discharge times were not different. On the first postoperative day, more subjects who received B were satisfied with their anaesthesia experience (P less than 0.05). Butorphanol 20 micrograms.kg-1 is an acceptable alternative analgesic in general anaesthesia for ambulatory laparoscopy.
Geometrical Barriers and the Growth of Flux domes in Thin Ideal Superconducting Disks

When an ideal (no bulk pinning) flat type-II superconducting disk is subjected to a perpendicular magnetic field H a , the first vortex nucleates at the rim when H a =H 0, the threshold field, and moves quickly to the center of the disk. As H a increases above H 0, additional vortices join the others, and together they produce a domelike field distribution of radius b. In this paper I present analytic solutions for the resulting magnetic-field and sheet-current-density distributions. I show how these distributions vary as b increases with H a , and I calculate the corresponding field-increasing magnetization.
An efficient algorithm for name resolution in computer networks

Abstract The name resolution problem is to determine the current location of a resource when it is requested. In a large network, each site cannot store the locations of all resources available in the network and hence a search algorithm may have to be invoked when a program uses a remote resource. We present a search algorithm that requires considerably less bandwidth than the currently used flooding algorithms. The bandwidth and search time of the proposed algorithm are analyzed and compared with a controlled flooding algorithm. We also explore the relationship between the bandwidth required by the search algorithms and the network connectivity.
Synthesis of Superconducting Oxides and Oxide/Metal Composites by Oxidation of Metallic Precursors

One method for the synthesis of superconducting oxides is high temperature oxidation of a metallic alloy (a metallic precursor) that contains the metallic constituents of the oxide. In addition, a noble metal can be added to the precursor such that, after oxidation, a two phase, finely divided oxide/metal composite results. Superconducting oxides have been produced from Eu-Ba-Cu and Yb-Ba-Cu alloys by oxidizing the alloys at 300°C followed by an “oxygen anneal” at elevated temperatures. Similarly, a Eu1,Ba2Cu3O7−x /Au composite has been formed from a quaternary metallic precursor. each case an onset of superconductivity occurred at about 92K. This approach to producing superconducting oxides is felt to have a number of advantages associated with it, not the least of which is the improvement of the mechanical properties of the superconducting product.
Boundary control of a two‐dimensional flexible rotor

In this paper, we present the design of boundary controllers for a two-dimensional, spinning flexible rotor system. Specifically, we develop a model-based boundary controller which exponentially regulates the rotor's displacement and the angular velocity tracking error, and an adaptive boundary controller which asymptotically achieves the same control objective while compensating for parametric uncertainty. As opposed to previous boundary control work, which focused on the velocity setpoint problem and placed restrictions on the magnitude of the desired angular velocity setpoint, the proposed control architecture achieves angular velocity tracking with no restrictions on the magnitude of the desired velocity trajectory. Experimental results conducted on a flexible rotor tested are presented to illustrate the feasibility of implementing the proposed boundary control laws. Copyright © 2001 John Wiley & Sons, Ltd.
Electoral Cycles and Defense Spending A Comparison of Israel and the United States

This article compares the impact of electoral cycles on military spending in Israel and the United States. The analysis of the three major components of the Israeli military budget reveals that elections do influence military expenditures in Israel, though in a very different way than in the United States. Based on these findings, a number of theoretical modifications for the argument about “electoral cycles and defense spending” are proposed.
Construction of signal-dependent Cohen's-class time-frequency distributions using iterative blind deconvolution

The problem of kernel design for Cohen time-frequency distributions is formulated as a blind deconvolution problem. It is shown that the iterative blind deconvolution method (IBDM) used in image restoration problems can be successfully applied to solve the kernel design problem. We obtain the following results: (1) the rate of convergence depends on which domains the constraints are imposed (2) certain constraints are needed for algorithm convergence (3) the more constrained the kernel design is, the faster the rate of convergence (4) there are tradeoffs between constraints, e.g., compact support vs. satisfaction of marginals; (5) time-frequency distributions which are more amenable to visual interpretation can be obtained using this algorithm.
Sudden stops: Determinants and output effects in the first era of globalization, 1880–1913

Abstract We study the determinants and output effects of sudden stops in capital inflows during an era of intensified globalization from 1880 to 1913. Higher levels of exposure to foreign currency debt and large current account deficits associated with reliance on foreign capital greatly increased the likelihood of experiencing a sudden stop. Trade openness and strong reserve positions had the opposite effect. Sudden stops accompanied by financial crises are associated with drops in output per capita below trend equal to three to four percent. Frictions in the international capital markets of the day are a likely candidate for these output losses. Sudden stops connected with crises do not seem to bring trend growth downwards. Sudden stops not connected with crises appear to be associated with significant declines in trend growth.
Noetherian Centralizing Hopf Algebra Extensions and Finite Morphisms of Quantum Groups

We study finite centralizing extensions A ⊂ H of noetherian Hopf algebras. Our main results provide necessary and sufficient conditions for the fibres of the surjection spec H [Rarr ]spec A to coincide with the X -orbits in spec H , where X denotes the finite group of characters of H that restrict to the counit of A . In particular, all of the fibres are X -orbits if and only if the fibre over the augmentation ideal of A is an X -orbit. An application to the representation theory of quantum function algebras, at roots of unity, is presented.
One-step synthesis and redox properties of dodecahydro-3a,9a-diazaperylene—the most easily oxidized p-phenylenediamine

Dodecahydro-3a,9a-diazaperylene (DHDAP) was prepared in one step from p-phenylenediamine and 1-bromo-3-chloropropane, and its first redox potential is 292 mV more negative than the first redox potential of N,N,N′,N′-tetramethyl-p-phenyl enediamine (TMPD), thus becoming the most easily oxidized p-phenylenediamine homologue.
Evidence for J- and H-band excess in classical T Tauri stars and the implications for disk structure and estimated ages

We argue that classical T Tauri stars (CTTSs) possess significant nonphotospheric excess in the J and H bands (1.25 and 1.66 μm, respectively). We first show that normalizing the spectral energy distributions (SEDs) of CTTSs to the J band leads to a poor fit of the optical fluxes (which are systematically overestimated), while normalizing the SEDs to the IC band (0.8 μm) produces a better fit to the optical bands and in many cases reveals the presence of a considerable excess at J and H. Near-infrared spectroscopic veiling measurements from the literature support this result. We find that J- and H-band excesses correlate well with the K-band (2.2 μm) excess and that the J - K and H - K colors of the excess emission are consistent with that of a blackbody at the dust sublimation temperature (~1500-2000 K). We propose that this near-IR excess originates at a hot inner rim, analogous to those suggested to explain the "near-IR bump" in the SEDs of Herbig Ae/Be stars. To test our hypothesis, we use the model presented by Dullemond and coworkers to fit the photometry data between 0.5 and 24 μm of 10 CTTSs associated with the Chamaeleon II molecular cloud. We find that simple models that include luminosities calculated from IC-band magnitudes and an inner rim may account for the reported J- and H-band excesses. The models that best fit the data are those in which the inner radius of the disk is larger than expected for a rim in thermal equilibrium with the photospheric radiation field alone. In particular, we find that large inner rims are necessary to account for the mid-infrared fluxes (3.6-8.0 μm) obtained by the Spitzer Space Telescope (Spitzer). The large radius could be explained if, as proposed by D'Alessio and colleagues, the UV radiation from the accretion shock significantly affects the sizes of the inner holes in disks around CTTSs. Finally, we argue that deriving the stellar luminosities of CTTSs by making bolometric corrections to the J-band fluxes, which is the "standard" procedure for obtaining CTTS luminosities, systematically overestimates these luminosities. The overestimated luminosities translate into underestimated ages when the stars are placed in the H-R diagram. Thus, the results presented herein have important implications for the dissipation timescale of inner accretion disks.
Three New Supernova Remnant OH Masers Near the Galactic Center: Evidence for Large-Scale Maser Emission from Supernova Remnants

A survey of the inner 8°×1° of the Galactic plane toward the Galactic center has been carried out at the 1720 MHz transition of the OH molecule using the VLA in its D configuration with a resolution of ≈70''×45''. The detection of compact 1720 MHz OH masers associated with three supernova remnants G357.7+0.3, G1.13-0.1 (Sgr D), and G1.4-0.1 as well as new extended maser line emission from G357.7+0.3 and G357.7-0.1 (the Tornado Nebula) were then followed up by A-array observations with spectral and spatial resolutions of 0.3 km s-1 and ≈3''×2'', respectively. The 1720 MHz OH maser line emission is considered to be a powerful shock diagnostic and is collisionally pumped by H2 molecules at the site where C-type supernova shocks drive into adjacent molecular clouds. The new observations show clear evidence of extended features coincident with compact and bright masers, the best example of which is a coherent feature over a scale of about 20 pc surrounding the shell of the SNR G357.7+0.3. We argue that this remarkable feature is an OH maser and is physically associated with the remnant. This implies that the ambient molecular cloud is uniform in its density and temperature with a restricted range of pumping conditions and survives the passage of a large-scale shock front.
Fabrication of large-area CCD detectors on high-purity, float-zone silicon

Abstract One of the problems with the fabrication of radiation detectors on high-purity, float-zone silicon is that such material is more susceptible to the formation of dislocations during high-temperature processing than Czochralski-grown material. We describe here the impact of dislocations on the electrical performance of a 1024 × 1024-pixel CCD imager that we have developed as the principal detector for the Advanced X-ray Astrophysical Facility. A technique has been developed to determine both the location (to within one gate of a pixel) and the trapping parameters of a dislocation. The processes giving rise to dislocation formation and propagation will be discussed, and techniques will be described for maintaining wafers free of dislocations even after the many high-temperature steps necessary for CCD fabrication.
A convenient preparation of 3-mercaptopicolinic acid

Abstract A procedure for the convenient preparation of 3-mercaptopicolinic acid from readily available starting materials is described.
FUTURE PLANETARY PROBES FOR JUPITER AND SATURN

The paper describes a study conducted to identify the technology developments that would allow deep atmospheric investigations of Jupiter and Saturn to proceed beyond currently planned investigation of the upper atmosphere. The study considered a deep probe mission that would provide the capability to scientifically examine planetary atmospheres to the 1000-bar level and 1400-K level. The major conclusions of the study are that (1) a probe designed for Jupiter can be used with minor changes for Saturn, (2) new science instrument technology developments are required, and (3) the only new technology developments required in the engineering subsystem are high pressure thermal insulation materials and advanced data processing techniques.
Guilt, fear, stigma and knowledge gaps: ethical issues in public health communication interventions.

Public health communication campaigns have been credited with helping raise awareness of risk from chronic illness and new infectious diseases and with helping promote the adoption of recommended treatment regimens. Yet many aspects of public health communication interventions have escaped the scrutiny of ethical discussions. With the transference of successful commercial marketing communication tactics to the realm of public health, consideration of ethical issues becomes an essential component in the development and application of public health strategies. Ethical issues in public health communication are explored as they relate to eight topics: ‘targeting’ and ‘tailoring’ public health messages to particular population segments; obtaining the equivalence of informed consent; the use of persuasive communication tactics; messages on responsibility and culpability; messages that apply to harm reduction; and three types of unintended adverse effects associated with public health communication activities that may label and stigmatise, expand social gaps, and promote health as a value. We suggest that an ethical analysis should be applied to each phase of the public health communication process in order to identify ethical dilemmas that may appear subtle, yet reflect important concerns regarding potential effects of public health communication interventions on individuals and society as a whole.
Benzyl alcohol and titanium tetrachloride - A versatile reaction system for the nonaqueous and low-temperature preparation of crystalline and luminescent titania nanoparticles

The reaction between TiCl4 and benzyl alcohol is a simple and nonaqueous procedure for the synthesis of highly crystalline titania nanoparticles at temperatures as low as 40 °C. XRD measurements prove the exclusive presence of the anatase phase. The particle growth depends strongly on temperature so that with the appropriate thermal conditions the particle size can be selectively adjusted in the range of 4−8 nm. Fine-tuning of the particle size is possible by a proper choice of the relative amounts of benzyl alcohol and titanium tetrachloride. Lowering the titanium tetrachloride concentration leads to a considerable decrease of particle size. BET measurements show particularly high surface areas, up to 345 m2/g for the smallest particles and 115 m2/g for the calcined material. TEM investigations reveal that the nanoparticles are nearly uniform in size and shape. The as-synthesized particles display only minor agglomeration, whereas the calcined material consists of completely nonagglomerated particles, wi...
Apparent horizons in simplicial Brill wave initial data

We use Regge calculus to construct initial data for a particular class of Brill wave metrics and compare the results with a corresponding continuum solution, finding excellent agreement. We then search for trapped surfaces in both sets of initial data, and provide an independent verification of the existence of an apparent horizon once a critical gravitational wave amplitude is passed. Our estimate of this critical value, using both the Regge and continuum solutions, supports recent findings.