cssi/SciSciGPT-SciSciNet huggingface dataset:
The role of hysteroscopic biopsy in obtaining specimens for cytogenetic evaluation in missed abortion prior to suction dilatation and curettage.

Aim:To estimate whether hysteroscopic-guided biopsy of gestational sac(s) in first trimester missed abortion increases the sensitivity of detecting aneuploidy compared to washing and careful specimen collection after suction dilatation and curettage (D&C). Materials and Methods:Thirty-five patients with first trimester missed abortion of which 25 underwent 29 suction D&Cs and 10 underwent hysteroscopic-guided biopsy of 12 gestational sacs prior to suction D&C. The karyotype of products of conception specimens were analyzed by G-banding techniques. Results:The percentage of specimens with 46,XX, 46,XY and aneuploidy were not significantly different in the hysteroscopic group [4/12 (33.3%), 3/12 (25.0%) and 5/12 (41.7%)] compared with the D&C group [8/29 (27.6%), 5/29 (17.2%) and 16/29 (55.2%)]. Although parity differed significantly between groups, it did not hold in a multivariable logistic regression model built to estimate whether the parity, gestational age and specimen collection method predict the likelihood of detecting a 46,XX chromosomal complement. Conclusions:Direct hysteroscopic-guided biopsies of gestational sac(s) do not increase the sensitivity of conventional cytogenetics for detecting aneuploidy when compared to specimens obtained by washing and microscopic identification of villi or fetal tissue after suction D&C.
Walker's Cancellation Theorem

Walker's cancellation theorem says that, if B ⊕ Z is isomorphic to C ⊕ Z in the category of abelian groups, then B is isomorphic to C. We construct an example in a diagram category of abelian groups where the theorem fails. As a consequence, the original theorem does not have a constructive proof even if B and C are subgroups of the free abelian group on two generators. Both of these results contrast with a group whose endomorphism ring has stable range one, which allows a constructive proof of cancellation and also a proof in any diagram category.
Induced strain actuation of isotropic and anisotropic plates

The development and experimental verification of the induced strain actuation of plate components of an intelligent structure is presented. Equations relating the actuation strains, created by induced strain actuators, to the strains induced in the actuator/substrate system are derived for isotropic and anisotropic plates. Plate strain energy relations are also developed. Several exact solutions are found for simple actuator/substrate systems, and a general procedure for solving the strain energy equations with a Rayleigh-Ritz procedure is formulated. Approximate Ritz solutions lead to both an understanding of the system design parameters, and to detailed models of cantilever plate systems. Simple test articles were used to verify the accuracy of the basic induced strain actuator/substrate system models, and cantilever plate test articles were built and tested to verify the ability of the models to predict the strains induced in systems with extensive stiffness coupling and complicated boundary conditions.
The evolution of a digital ecosystem

I am studying the evolution of digital ecosystem, which is characterized as an ongoing recombination of heterogeneous digital components such as Application Programming Interface (API) provided by firms including a focal platform owner. I am focusing on the all versions of 23,985 WordPress plug-ins' source codes from 2004 to 2014. A generative model of network is applied to capture how network centrality and the hierarchical order of sub-network in a network change over time. The studies observe the distinct pattern of the co-evolution of digital ecosystems compared to other open systems.
Are bank shareholders enemies of regulators or a potential source of market discipline

Abstract In moral hazard models, bank shareholders have incentives to transfer wealth from the deposit insurer – that is, maximize put option value – by pursuing riskier strategies. For safe banks with large charter value, however, the risk-taking incentive is outweighed by the possibility of losing charter value. Focusing on the relationship between Tobin’s q and an ex ante measure of the failure probability, this paper develops a semi-parametric model for estimating the critical level of bank risk at which put option value starts outweighing charter value. From these estimates, we infer the prevalence of moral hazard. Examining publicly held bank holding companies (BHC) during the tumultuous 1986–1992 period, we find that shareholders’ risk-taking incentives were confined to a small fraction of highly risky institutions. Furthermore, our analysis shows that the inflection point at which banks begin to tilt in favor of moral hazard increased substantially in 1993–2005. These findings are encouraging to bank regulators and legislators because they indicate that tighter capital rules and more rigorous supervision introduced by several legislative initiatives in the 1990s have helped squeeze a lot of the moral hazard incentives out of the banking system.
MAXIMUM VARIATION OF TOTAL RISK

Abstract Let Z > 0 be a random time. The total risk of discovering Z in the next time interval ( t , t + d t ) is never more variable than an exponential of mean one, which is achieved when the information up to time t is σ ( Z ∧ t ).
Solid Propellant Sandwich Deflagration Analysis

A theoretical solution has been obtained for the shape of a deflagrating ammonium perchlorate surface when it is adjacent to an inert, pyrolysing, dry binder. The eigenvalue, the regression rate, is shown to be independent of binder type and very close to the burn rate of pure AP, as has been experimentally observed. A slope discontinuity of the surface should exist at the binder-oxidizer interface and typical binders should incline very near to 90° to the nearly horizontal AP surface, at the junction of the two. The transition from AP to binder should take place on a distance scale of the order of microns and all results are quite insensitive to pressure level.
Boundary conditions for the gravitational field

A review of the treatment of boundaries in general relativity is presented with the emphasis on application to the formulations of Einstein's equations used in numerical relativity. At present, it is known how to treat boundaries in the harmonic formulation of Einstein's equations and a tetrad formulation of the Einstein–Bianchi system. However, a universal approach valid for other formulations is not in hand. In particular, there is no satisfactory boundary theory for the 3+1 formulations which have been highly successful in binary black hole simulation. I discuss the underlying problems that make the initial-boundary-value problem much more complicated than the Cauchy problem. I review the progress that has been made and the important open questions that remain.Science is a differential equation. Religion is a boundary condition. (Alan Turing, quoted in J D Barrow, ‘Theories of Everything’)
Synthesis of (±)tylophorine by the intramolecular cycloaddition of an azide with an ω-chloroalkene

Abstract Cyclization of (Z)-1-(2-chloromethyl)phenyl-5-azidopent-1-ene 10 in benzene at 120°C followed by treatment with sodium borohydride produced 1,2,3,5,10,10a-hexahydropyrrolo[1,2- b ]isoquinoline 11 in 71% yield. A similar cyclization of (Z)-2,3,6,7-tetramethoxy-9-(5-azido-1-pentenyl)-10-chloromethylphenanthrene 3 gave the phenanthroindolizidine alkaloid (±)- tylophorine 5 in 82% yield. These reactions proceed by intramolecular 1,3-dipolar cycloaddition of the azide onto the alkene followed by loss of nitrogen from the triazoline intermediate to give an imine The imine is N -alkylated in situ by the pendant benzyl chloride to provide an iminium ion, which is reduced by sodium borohydride to afford the indolizidines. The synthesis of (±)-tylophorine was acomplished in 11 steps from homoveratric acid in 5% overall yield.
A bond graph model incorporating sensors, actuators, and vehicle dynamics for developing controllers for vehicle safety

Abstract The process of developing controllers for vehicle dynamics requires reasonable models that expose the important dynamic effects without being excessively complicated. The controllers require sensors, signal processing, and actuation, and these parts must be incorporated and demonstrated using vehicle models. Bond graphs are a concise pictorial representation of all types of interacting energy domains, and are an excellent tool for representing vehicle dynamics with associated control hardware. This paper develops a four-wheel, nonlinear vehicle dynamic model with electrically controlled brakes and steering, as well as control at each suspension corner. Controllers are not developed here but are demonstrated through simulation.
Rescattering effects in hadron-nucleus and heavy-ion collisions

We review the extension of the factorization formalism of perturbative QCD to coherent soft rescattering associated with hard scattering in high energy nuclear collisions. We emphasize the ability to quantify high order corrections and the predictive power of the factorization approach in terms of universal non-perturbative matrix elements. Although coherent rescattering effects are power suppressed by the hard scales of the scattering, they are enhanced by the nuclear size and could play an important role in understanding the novel nuclear dependence observed in high energy nuclear collisions.
Comet 17P/Holmes in Outburst: The Near Infrared Spectrum

Jupiter family comet 17P/Holmes underwent a remarkable outburst on UT 2007 October 24, in which the integrated brightness abruptly increased by about a factor of a million. We obtained near infrared (0.8-4.2 μm) spectra of 17P/Holmes on UT 2007 October 27, 28, and 31, using the 3.0 m NASA Infrared Telescope Facility atop Mauna Kea. Two broad absorption bands were found in the reflectance spectra with centers (at 2 μm and 3 μm, respectively) and overall shapes consistent with the presence of water ice grains in the coma. Synthetic mixing models of these bands suggest an origin in cold ice grains of micron size. Curiously, though, the expected 1.5 μm band of water ice was not detected in our data, an observation for which we have no explanation. Simultaneously, excess thermal emission in the spectra at wavelengths beyond 3.2 μm has a color temperature of 360 ± 40 K (corresponding to a superheat factor of ~2.0 ± 0.2 at 2.45 AU). This is too hot for these grains to be icy. The detection of both water ice spectral features and short-wavelength thermal emission suggests that the coma of 17P/Holmes has two components (hot, refractory dust and cold ice grains) which are not in thermal contact. A similarity to grains ejected into the coma of 9P/Tempel 1 by the Deep Impact spacecraft is noted.
Recent Advances in the Science of Voter Mobilization

Until recently, the study of voting behavior was dominated by survey research. Concerned that survey data may provide an inadequate basis for causal inference, scholars in recent years have turned to field experimentation, which relies on random assignment of voters to treatment and control groups in real-world settings. The articles in this volume attest to the measurable advances in knowledge that come through the repeated application of a powerful research design.
Effect of Na2O Additions in the Crystallization of Barium Ferrite from a BaO-B2O3-Fe2O3 Glass

A glass crystallization method was utilized to synthesize nano-sized BaO.6Fe 2 O 3 platelets from a 0.412BaO-0.258B 2 O 3 -0.330Fe 2 O 3 batch composition. Quenched ribbons were inhomogeneous, showing microclustering and ∼1 μm hematite crystals. Na 2 O substitutions for BaO greatly enhanced the glass-forming tendency of quenched ribbons, though quenched-in ∼0.5 μm barium ferrite crystals were infrequently present. The improved homogeneity with Na 2 O substitution was attributed to lower vapor pressure of BaO during batch melting, which increased its retention in the as-quenched ribbons. Quantities of BaO equal to or in excess of Fe 2 O 3 allowed iron ions to adopt stable network positions in the glass melt. With Na 2 O substitution, devitrification of dispersed ∼40 nm barium ferrite particles from phase-separated regions occurred after secondary heat treatment. 5 mol% Na 2 O batch substitution showed the lowest crystallinity in the as-quenched ribbons, and the highest crystallinity after secondary heat treatment. After optimum devitrification, the maximum values of saturation magnetization and coercivity were 21.22 emu/g and 2.82 kOe, respectively.
AhR-mediated gene expression in the developing mouse telencephalon

Abstract We hypothesize that TCDD-induced developmental neurotoxicity is modulated through an AhR-dependent interaction with key regulatory neuronal differentiation pathways during telencephalon development. To test this hypothesis we examined global gene expression in both dorsal and ventral telencephalon tissues in E13.5 AhR−/− and wildtype mice exposed to TCDD or vehicle. Consistent with previous biochemical, pathological and behavioral studies, our results suggest TCDD initiated changes in gene expression in the developing telencephalon are primarily AhR-dependent, as no statistically significant gene expression changes are evident after TCDD exposure in AhR−/− mice. Based on a gene regulatory network for neuronal specification in the developing telencephalon, the present analysis suggests differentiation of GABAergic neurons in the ventral telencephalon is compromised in TCDD exposed and AhR−/− mice. In addition, our analysis suggests Sox11 may be directly regulated by AhR based on gene expression and comparative genomics analyses. In conclusion, this analysis supports the hypothesis that AhR has a specific role in the normal development of the telencephalon and provides a mechanistic framework for neurodevelopmental toxicity of chemicals that perturb AhR signaling.
A variation of the Fischer indolization involving condensation of quinone monoketals and aliphatic hydrazines.

The indole ring system is one of the most ubiquitous heterocycles in nature. Many indole-containing natural products show a wide scope of biological activities, in particular because they bind to many receptors with high affinity. Since Baeyer s first synthesis of indole from oxindole in 1866 (indigo!isatin!oxindole!indole), numerous methods for the synthesis of indoles have been reported. One of the most efficient and widely employed syntheses is the Fischer indolization discovered in 1883. Compared with other indole syntheses, the importance of Fischer indolization lies in its simplicity and convenience, that is, formation of a critical C C bond to an unactivated aromatic carbon through a [3,3] sigmatropic rearrangement of enolizable Narylhydrazones. After more than a century of development, the Fischer indole synthesis remains a reliable and versatile method for the preparation of a variety of indole natural products and medicinal compounds. Many new variations have been developed in recent years. Most recently, the first catalytic asymmetric version of Fischer indole synthesis was reported by the group of List. Although the Fischer indole synthesis is widely used, several disadvantages still remain. The classical Fischer indole synthesis starts with arylhydrazines, which are generally made either from anilines through diazonium salts, or from aryl halides through transitionmetal-mediated coupling reactions. These processes involve the use of aniline precursors and toxic reagents (nitrous acid, stannous chloride, etc.) and potentially explosive diazonium intermediates, or expensive transition metals. We report herein a novel variation of the Fischer indolization involving a one-pot condensation of quinone monoketals with aliphatic hydrazines (Scheme 1). To the best of our knowledge, this is the first Fischer-type indole synthesis using an aliphatic hydrazine as the nitrogen source and a quinone monoketal as a masked benzene ring. We envisioned that condensation of quinone monoketal 1 and aliphatic hydrazine 2 would ultimately lead to an indole via alkylaryldiazene 5 and arylhydrazone intermediate 6, as illustrated in Scheme 2. The feasibility of this method relies on the initial formation of alkylaryldiazene 5 from a 1,2addition/dehydration sequence. It should be noted that there has been no report on the synthesis of alkylaryldiazenes 5 from quinone derivatives and aliphatic hydrazines, although arylaryldiazenes (azobenzenes) have been synthesized from condensations of arylhydrazines with quinones, quinols, quinone monoketals, and quinone bisketals. There is a single report on the condensation of an aliphatic hydrazine (N,N-dimethylhydrazine) with naphthoquinone monoketal, which, however, gave a 1,4-addition product in high yield. Therefore, our first object was to test the practicality of the Scheme 1. Strategies for the synthesis of indoles.
Engineering Complex Embedded Systems with State Analysis and the Mission Data System

It has become clear that spacecraft system complexity is reaching a threshold where customary methods of control are no longer affordable or sufficiently reliable. At the heart of this problem are the conventional approaches to systems and software engineering based on subsystem-level functional decomposition, which fail to scale in the tangled web of interactions typically encountered in complex spacecraft designs. Furthermore, there is a fundamental gap between the requirements on software specified by systems engineers and the implementation of these requirements by software engineers. Software engineers must perform the translation of requirements into software code, hoping to accurately capture the systems engineer's understanding of the system behavior, which is not always explicitly specified. This gap opens up the possibility for misinterpretation of the systems engineer s intent, potentially leading to software errors. This problem is addressed by a systems engineering methodology called State Analysis, which provides a process for capturing system and software requirements in the form of explicit models. This paper describes how requirements for complex aerospace systems can be developed using State Analysis and how these requirements inform the design of the system software, using representative spacecraft examples.
On Nagata's Conjecture

Abstract This paper gives an improved lower bound on the degrees d such that for general points p 1 ,…, p n ∈ P 2 and m > 0 there is a plane curve of degree d vanishing at each p i with multiplicity at least m .
Stereoselective radical cyclizations of N-(2-halobenzoyl)-cyclic ketene-N,X(X=O, S)-acetals

Abstract 2-Alkyloxazolines and 2-alkylthiazolines react with 2-halobenzoyl chlorides to form N-(2-halobenzoyl)-cyclic ketene-N,O-acetals and N-(2-halobenzoyl)-cyclic ketene-N,S-acetals in excellent yields, respectively. These ketene acetals readily undergo stereocontrolled aryl radical cyclizations to afford the central six-membered rings of substituted-2,3,10,10α-tetrahydrooxazolo[3,2-b]isoquinolin-5-ones and their 2,3,10,10α-tetrahydrothiazolo[3,2-b]isoquinolin-5-one analogs. The tertiary N,O- and N,S-radicals formed upon aryl radical reaction at the ketene-N,X(X=O, S)-acetal double bond appear to have reasonable stability. The stereoselectivity in hydrogen abstractions by these intermediate radicals from both Bu3SnH and (Me3Si)3SiH was investigated. The N,S-heterocyclic fused ring products may have potential medical value.
Changing cytologic and histologic utilization patterns in the diagnosis of 515 primary lung malignancies

BACKGROUND Over the last decade, the specimen types used to diagnose primary pulmonary malignancies at the authors' institution have changed in terms of their frequency of submission. METHODS The authors reviewed pathologic findings in 216 cases of primary lung carcinoma diagnosed during the years 1983-1984 (earlier period) and compared these with the findings in 299 cases diagnosed during the years 1993-1994 (later period). RESULTS The total number of transbronchial fine-needle aspirates (TBNA) increased from 13 to 206 (P < 0.0001), the total number of sputum (SP) samples declined from 236 to 36 (P < 0.0001), and the total number of forceps endobronchial biopsy (FBX) specimens increased from 61 to 119 (P = 0.0023) between the earlier period and the later period. The positivity rate of some specimen types was similar for these two periods (transthoracic percutaneous fine-needle aspirate [PFNA], 95% and 97%; bronchial washings, 61% and 60%), but the positivity of others improved by a statistically nonsignificant degree (bronchial brushings, 61-71%; FBX, 59-69%). The positivity of TBNA was 57% in 1993-1994. The collective positivity of bronchoscopic cytology specimens was significantly higher than simultaneous FBX during both periods (P = 0.0032), but bronchoscopic histology and cytology were complementary. The positivity of fiberoptic bronchoscopy (FOB) improved significantly, from 72% in 1983-1984 to 85% in 1993-1994 (P = 0.0059). During both periods, an equivalent proportion of patients were subjected to each of 3 major invasive sampling procedures (FOB, 70%; PFNA, 20%; open surgical biopsy, 10%). Fifteen patients were diagnosed by SP cytology without an invasive procedure in 1983-1984, but none were diagnosed by SP cytology in 1993-1994. CONCLUSIONS TBNA and increased utilization of FBX have displaced postbronchoscopy SP examination, generating higher positivity for FOB. Bronchoscopic cytology and histology were complementary, but radiologically guided fine-needle aspiration was the procedure with the highest positivity. Cancer (Cancer Cytopathol) 1997; 81:105-15. © 1997 American Cancer Society.
Electron-neutrino Majorana mass and solar neutrino oscillations

Abstract Assuming the Majorana masses of νe and the linear combination cντ−sνμ to be equal from their couplings to a heavy scalar triplet ξ, I show that their radiative splitting is given by Δm 2 /m ν 2 =(3c 2 /4π 2 )(G F / 2 )m τ 2 ln (m ξ 2 /m W 2 ) . This is applicable to the small-angle matter-enhanced oscillation solution of the solar neutrino deficit and restricts mν to be between 0.20 and 0.36 eV if c2=0.7 and mξ=1014 GeV.
Cation radical pericyclic reactions: Cyclopropanation

Triarylaminium salts smoothly catalyze the cyclopropanation of dienes, styrenes and tetrasubstituted alkenes by ethyl diazoacetate. The reactions are regioselective and, in the case of additions to conjugated dienes, cyclopropane-periselective. A cation radical chain mechanism involving carbene transfer from ethyl diazoacetate to a substrate cation radical is proposed.
Calcium, Cell Function and Cell Death

The nature of the biologic mechanism(s) which initiate and perpetuate the aging process is still under intensive investigation. Although those with vested interests in “aging research” would agree that the programming of the aging phenomenon is related to specific acquired and/or genetic molecular dysfunctions which condition DNA and protein synthesis, and post-translational events in cells, the fundamental “trigger” mechanism(s) which activates mammalian senescence has yet to be discovered. A number of theories have been promulgated to account for the molecular cellular dysfunctions which attend the senescent process. These include: (a) alterations in host-defense systems and cell-mediated immunity; (b) progressive accumulations of circulating “toxic” substances which damage DNA; (c) an acquired inability to destroy “free-radicals”, the latter resulting in the cellular accumulation of superoxide and hydrogen peroxide type reactants and a gradual decline in cellular integrity; (d) cellular “commitment” theories which stress programmed aging and finite replicative life-span of cells; and (e) gradual alterations in those mechanisms which regulate cytosolic calcium concentration resulting in molecular disarray, decrease in, cellular viability and cell death.
Finding minimum cost tool grouping schemes on machining systems

Changing worn tools is a major concern in planning operations on machining systems. Strategies for replacing tools range from changing each tool as it reaches its projected tool life, to changing all tools when the tool with the shortest life on the machining system is expended. Intermediate strategies involve changing tools in groups. Each of these strategies has two cost components associated with it: (1) the cost of lost production due to machine tool stoppage, and (2) the cost of unused tool life. The best tool grouping strategy minimizes the combined cost of lost production. In this paper we present an approach for finding good tool grouping strategies from inputs that include the tool utilization for a given machining application, and the tooling and machining system costs. A genetic algorithm is used as the underlying optimization paradigm for finding the minimum cost strategy. An example is presented for a part produced on a machining center.
Extrasolar giant planets under strong stellar irradiation

We investigate irradiation of extrasolar giant planets (EGPs) by treating the radiative transfer in detail, so that the flux from the parent star interacts with all relevant depths of the planetary atmosphere with no need for a preassumed albedo. Rayleigh scattering (in dust-free models) increases the EGP's flux by orders of magnitude shortward of the Ca II H and K doublet (3930 A), and the spectral features of the parent star are exactly reflected. The inclusion of dust increases the reflected flux in the blue. In the optical and near-IR, the thermal absorption of the planet takes over, but the absorption features are changed by the irradiation.
Laser‐Induced Calcite—Aragonite Transition

High-pressure phases of CaCO3, namely aragonite, calcite II, and possibly calcite III, were synthesized in air by exposing 10- to 20-μm-size particles of CaCO3 (calcite I phase) to a CO2 laser radiation at short pulse lengths (≤0.1 ms). The process, therefore, has the same effect as exposing the particles to at least several hundred megapascals pressure. Processing at higher pulse lengths resulted in the decomposition of CaCO3 to CaO and CO2. The extent of decomposition increased with increasing pulse length.
Systems of distant representatives in Euclidean space

Given a finite family of sets, Hall's classical marriage theorem provides a necessary and sufficient condition for the existence of a system of distinct representatives for the sets in the family. Here we extend this result to a geometric setting: given a finite family of objects in the Euclidean space (e.g., convex bodies), we provide a sufficient condition for the existence of a system of distinct representatives for the objects that are also distant from each other. For a wide variety of geometric objects, this sufficient condition is also necessary in an asymptotic sense (i.e., apart from constant factors, the inequalities are the best possible). Our methods are constructive and lead to efficient algorithms for computing such representatives.
Reactive impedance of a smooth toroidal chamber below the resonance region.

We evaluate the longitudinal coupling impedance of a smooth toroidal vacuum chamber in the domain of frequencies below the first synchronous resonant mode. The chamber was rectangular cross section. With infinite wall conductivity, as assumed here, the nonresonant impedance is purely reactive. It consists of a space charge term proportional to 1/{gamma}{sup 2} and a curvature term which survives at large {gamma}. In the entire subresonant domain, the curvature term is well-represented as a quadratic function of frequency, where h is the height of the chamber, RA is the trajectory radius and {nu} = {omega}h/c. The constants A and B are of order one, being nearly equal to one if the width of the chamber is somewhat greater than its height. Thus, ImZ/n from curvature is typically a very small fraction of an ohm below the resonance domain, which begins where {nu} > (A/h){sup 1/2}. Consequences for beam stability, if any, arise from high frequency resonances which can produce values of several ohms for Z/n.
Nonlinear aspects of the renormalization group flows of Dyson's hierarchical model

We review recent results concerning the renormalization group (RG) transformation of Dyson's hierarchical model (HM). This model can be seen as an approximation of a scalar field theory on a lattice. We introduce the HM and show that its large group of symmetry simplifies drastically the blockspinning procedure. Several equivalent forms of the recursion formula are presented with unified notations. Rigourous and numerical results concerning the recursion formula are summarized. It is pointed out that the recursion formula of the HM is inequivalent to both Wilson's approximate recursion formula and Polchinski's equation in the local potential approximation (despite the very small difference with the exponents of the latter). We draw a comparison between the RG of the HM and functional RG equations in the local potential approximation. The construction of the linear and nonlinear scaling variables is discussed in an operational way. We describe the calculation of non-universal critical amplitudes in terms of the scaling variables of two fixed points. This question appears as a problem of interpolation between these fixed points. Universal amplitude ratios are calculated. We discuss the large-N limit and the complex singularities of the critical potential calculable in this limit. The interpolation between the HM and more conventional lattice models is presented as a symmetry breaking problem. We briefly introduce models with an approximate supersymmetry. One important goal of this review is to present a configuration space counterpart, suitable for lattice formulations, of functional RG equations formulated in momentum space (often called exact RG equations and abbreviated ERGE).
Entry into the market for large transport aircraft

Abstract European governments have been accused of unfair trading practices in providing subsidies for market entry in the large commercial aircraft industry. A capacity game is calibrated for 1987 to 2006, showing that the disadvantage of late entry is overcome only after a long time. Hence, market entry is unlikely without government subsidies. The scale and scope effects of production outweigh the output-reducing effects of a monopoly. Government supported market entry as an anti-monopoly policy yields higher consumer welfare. Overall welfare is lower due to large losses in producer surplus.
Gravitation and Special Relativity

A mathematical derivation of Maxwell’s equations for gravitation, based on a mathematical proof of Faraday’s law, is presented. The theory provides a linear, relativistic Lagrangian field theory of gravity in a weak field, and paves the way to a better understanding of the structure of the energy-momentum tensor in the Einstein field equations. Hence it is directly relevant to problems in modern cosmology. The derivation, independent of the perturbation theory of Einstein’s equations, puts the gravitational and electromagnetic fields on an equal footing for weak fields, contrary to generally held views. The historical objections to a linear Lorentz invariant field theory of gravity are refuted.
The effect of wettability on three-phase relative permeability

We study three-phase flow in water-wet, oil-wet, and fractionally-wet sandpacks. We use CT scanning to measure directly the oil and water relative permeabilites for three-phase gravity drainage. In an analogue experiment, we measure pressure gradients in the gas phase to determine the gas relative permeability. Thus we find all three relative permeabilities as a function of saturation. We find that the gas relative permeability is approximately half as much in a oil-wet medium than in an water-wet medium at the same gas saturation. The water relative permeability in the water-wet medium and the oil relative permeability in the oil-wet medium are similar. In the water-wet medium the oil relative permeability scales as k ro ∼ S o 4 for S o > S or, where S or is the waterflood residual oil saturation. With octane as the oil phase, k ro ∼ S o 2 for S o < S or, while with decane as the oil phase, k ro falls sharply for S o < S or. The water relative permeability in the oil-wet medium resembles the oil relative permeability in the water-wet medium for a non-spreading oil such as decane. These observations can be explained in terms of wetting, spreading, and the pore scale configurations of fluid.
The Photometry of Undersampled Point-Spread Functions

An undersampled point-spread function (PSF) may interact with the microstructure of a solid-state detector such that the total flux detected can depend sensitively on where the PSF center falls within a pixel. Such intrapixel sensitivity variations will not be corrected by flat-field calibration and may limit the accuracy of stellar photometry conducted with undersampled images, as are typical for Hubble Space Telescope observations. The total flux in a stellar image can vary by up to 0.03 mag in F555W WFC images depending on how it is sampled, for example. For NIC3, these variations are especially strong, up to 0.39 mag, strongly limiting its use for stellar photometry. Intrapixel sensitivity variations can be corrected for, however, by constructing a well-sampled PSF from a dithered data set. The reconstructed PSF is the convolution of the optical PSF with the pixel response. It can be evaluated at any desired fractional pixel location to generate a table of photometric corrections as a function of relative PSF centroid. A caveat is that the centroid of an undersampled PSF can also be affected by the pixel response function; thus sophisticated centroiding methods, such as cross-correlating the observed PSF with its fully sampled counterpart, are required to derive the proper photometric correction.
Collapse and stability of necklace beams in Kerr media

We experimentally investigate necklace beams in Kerr media. For powers greater than one critical power for self-focusing per bead, we observe a transition from collective behavior to independent collapse of each of the beads.
Informational complexity criteria for regression models

Abstract This paper pursues three objectives in the context of multiple regression models: • • To give a rationale for model selection criteria which combine a badness-of-fit term (such as minus twice the maximum log likelihood) with a measure of complexity of model. We show that the ICOMP criterion introduced by Bozdogan can be seen as an approximation to the sum of two Kullback-Leibler distances, and that a criterion related to ICOMP arises as an approximation to the posterior expectation of a certain utility. • • To investigate the asymptotic consistency properties of the class of ICOMP criteria first in the case when one of the models considered is the true model and to introduce and establish a consistency property for the case when none of the models is the true model. In the first case, we find that asymptotic consistency holds under some assumptions; in this respect, some ICOMP criteria resemble Akaike's AIC, while other ICOMP criteria resemble Schwarz's BIC criterion. In the second case, in the context of regression models where at least one independent variable is missing in each model, we find that ICOMP, as well as AIC and BIC are all asymptotically consistent. • • To investigate the finite sample behavior of ICOMP criteria by means of a simulation study where none of the models considered is the true model. We find that the ICOMP criteria tend to agree with decisions based on minimizing the Kullback-Leibler distance between the true model and each estimated model more often than AIC or BIC. This conclusion also holds when the true model is one of the models considered.
Rare Charm Decays

Rare FCNC decay modes of charmed mesons are reviewed. The standard model predictions, including both short distance and long distance contributions, are summarized. Several new physics options that can give detectable signals are described.
Direct simulation of re-entry flows with ionization

The Direct Simulation Monte Carlo (DSMC) method is applied in this paper to the study of rarefied, hypersonic, re-entry flows. The assumptions and simplifications involved with the treatment of ionization, free electrons, and the electric field are investigated. A new method is presented for the calculation of the electric field and handling of charged particles with DSMC. In addition, a two-step model for electron impact ionization is implemented. The flowfield representing a 10-km/s shock at an altitude of 65 km is calculated. The effects of the new modeling techniques on the calculation results are presented and discussed.
Economic Recession, Teacher-Reported Cuts to School Resources, and Children's Economic and Psychiatric Problems in Young Adulthood

The study investigated whether cuts to school resources made during economic recession contribute to children's psychiatric and economic problems in early adulthood. The cohort consisted of 817 Finnish children. Data was gathered from teachers during a recession (child age 12) and from national registers on children's post-recession use of psychiatric and income benefit services (age 18–28). Children's need for remedial instruction, special education, or psychosocial services was associated with later use of income support and psychiatric services. Those receiving special education had an increased risk for adulthood use of psychiatric services as compared to those who needed, but did not receive, this service. A decrease in material resources and teachers' loss of motivation predicted children's later use of psychiatric services.
Delocalization of Vg1 mRNA from the vegetal cortex in Xenopus oocytes after destruction of Xlsirt RNA

The Xlsirts are a family of transcribed repeat sequence genes that do not code for protein. Xlsirt RNAs become localized to the vegetal cortex of Xenopus oocytes early in oogenesis, before the localization of the messenger RNA Vg1, which encodes a transforming growth factor-beta-like molecule involved in mesoderm formation, and coincident with the localization of Xcat2 transcripts, which encode a nanos-like molecule. Destruction of the localized Xlsirts by injection of antisense oligodeoxynucleotides into stage 4 oocytes resulted in the release of Vg1 transcripts but not Xcat2 transcripts from the vegetal cortex. Xlsirt RNAs, which may be a structural component of the vegetal cortex, are a crucial part of a genetic pathway necessary for the proper localization of Vg1 that leads to subsequent normal pattern formation.
An Empirical Analysis of Motives for Offshore Outsourcing by U.S. Firms

In light of the political debate on offshore outsourcing, this article examines firm financial characteristics associated with the probability of being identified as an outsourcer. In a sample of S&P 500 firms, we find that firms identified as outsourcers operate in more competitive industries and have relatively worse operating performance, higher administrative overhead, and higher labor overhead. These firm characteristics are consistent with cost-cutting objectives and the need to respond to competitive pressures. We find that the need to lower labor costs is a significant determinant of manufacturing firms locating operations overseas, while lowering administrative overhead influences service firms' outsourcing decisions. From a policy perspective, our results suggest that the political pressure to limit firms' ability to offshore outsource will likely reduce their flexibility to respond to operating and competitive challenges.
Morphological changes in polymer electrolyte cells

Abstract Rechargeable solid state batteries utilizing lithium anodes, V6O13 composite cathodes and polymer electrolytes made from polyethylene oxide - LiCF3SO3 complex - were investigated at 100°C. The cells exhibited good cycling and reversibility. Optical and scanning electron microscopy were used to study the morphological changes taking place at the electrodes and electrolyte as a function of cycle number. Post-mortem examination of the cell materials indicated that the structures of lithium, electrolyte and cathode become finer grained and hence smoother. In addition the structures were more coherent. The cathode appeared to undergo a re-healing process during the early stage of cycling. The results indicate that the structures are consistent with one another and that long cycle life can be obtained with these types of cells.
Information Technology and the Organization of Firms

This paper seeks to understand why improved information technology (IT) might strengthen the case for decentralization, as recent empirical work suggests. We study a firm with a headquarters and two managers, each of whom gathers information about her changing local environment. The firm earns a gross profit that depends on actions taken as well as the current local environments. More information permits better actions, and informationgathering costs drop as IT improves. When the firm is centralized, informationgathering expenditures are first best, but after the firm decentralizes, each manager becomes a self-interested player of a “sharing game” in which she collects a share of gross profit and bears the cost of her chosen informationgathering activities. The firm’s actions are determined by the information gathered at the equilibria of the game. As a result, the firm experiences a decentralization penalty, namely the change in net profit (gross profit minus informational costs) after decentralizing. If the penalty is small, then it is outweighed by the advantages of decentralizing—the vanishing of monitoring costs and perhaps the improved motivation of a decentralized manager’s staff. To gather information a manager chooses (once and for all) a partitioning of her possible local environments and then searches to find the set in which her current environment lies. Our main measure of a manager’s information cost is a technology parameter, θ, times the number of sets in her chosen partitioning. A second measure is θ times the partitioning’s “Shannon content,” which may be interpreted as average search time when search is efficient. We ask whether improved IT, i.e., a drop in θ, indeed lowers the decentralization penalty. We obtain a strongly affirmative answer to this question for both cost measures in a class of examples and a mixed answer when we generalize so as to preserve some of the key properties of those examples. In a parallel manner we explore another conjecture suggested in the empirical literature, namely that better IT I am very grateful to Eric Friedman for many discussions in early stages of this study and to two anonymous referees and a coeditor, whose suggestions led to a major reshaping of the paper. Support from National Science Foundation grant IIS0118600 is acknowledged gratefully. c
Statically safe program generation with SafeGen

SafeGen is a meta-programming language for writing statically safe generators of Java programs. If a program generator written in SafeGen passes the checks of the SafeGen compiler, then the generator will only generate well-formed Java programs, for any generator input. In other words, statically checking the generator guarantees the correctness of any generated program, with respect to static checks commonly performed by a conventional compiler (including type safety, existence of a superclass, etc.). To achieve this guarantee, SafeGen supports only language primitives for reflection over an existing well-formed Java program, primitives for creating program fragments, and a restricted set of constructs for iteration, conditional actions, and name generation. SafeGen's static checking algorithm is a combination of traditional type checking for Java, and a series of calls to a theorem prover to check the validity of first-order logical sentences, constructed to represent well-formedness properties of the generated program under all inputs. The approach has worked quite well in our tests, providing proofs for correct generators or pointing out interesting bugs.
SQUID detected NMR and NQR

Abstract The dc Superconducting QUantum Interference Device (SQUID) is a sensitive detector of magnetic flux, with a typical flux noise of the order 1 μΦ 0 Hz −1/2 at liquid helium temperatures. Here Φ 0 = ℏ /2 e is the flux quantum. In our NMR or NQR spectrometer, a niobium wire coil wrapped around the sample is coupled to a thin film superconducting coil deposited on the SQUID to form a flux transformer. With this untuned input circuit the SQUID measures the flux, rather than the rate of change of flux, and thus retains its high sensitivity down to arbitrarily low frequencies. This feature is exploited in a cw spectrometer that monitors the change in the static magnetization of a sample induced by radio frequency irradiation. Examples of this technique are the detection of NQR in 27 Al in sapphire and 11 B in boron nitride, and a level crossing technique to enhance the signal of 14 N in peptides. Research is now focused on a SQUID-based spectrometer for pulsed NQR and NMR, which has a bandwidth of 0–5 MHz. This spectrometer is used with spin-echo techniques to measure the NQR longitudinal and transverse relaxation times of 14 N in NH 4 ClO 4 , 63±6 ms and 22±2 ms, respectively. With the aid of two-frequency pulses to excite the 359 kHz and 714 kHz resonances in ruby simultaneously, it is possible to obtain a two-dimensional NQR spectrum. As a third example, the pulsed spectrometer is used to study NMR spectrum of 129 Xe after polarization with optically pumped Rb. The NMR line can be detected at frequencies as low as 200 Hz. At fields below about 2 mT the longitudinal relaxation time saturates at about 2000 s. Two recent experiments in other laboratories have extended these pulsed NMR techniques to higher temperatures and smaller samples. In the first, images were obtained of mineral oil floating on water at room temperature. In the second, a SQUID configured as a thin film gradiometer was used to detect NMR in a 50 μ m particle of 195 Pt at 6 mT and 4.2 K.
Nucleation and Crystallization as Induced by Bending Stress in Lithium Silicate Glass Fibers

Abstract Glass fibers of Li 2 O · 2SiO 2 (LS 2 ) and Li 2 O · 1.6SiO 2 (LS 1.6 ) compositions were heated near, but below, the glass transition temperature for different times while subjected to a constant bending stress of about 1.2 GPa. The nucleation density and the crystallization tendency, estimated by differential thermal analysis, of a glass sample in the vicinity of the maximum in bending stress increased relative to that of ‘stress-free’ glass fibers. LS 2 glass fibers were found more resistant to nucleation and crystallization than the LS 1.6 glass fibers. The scanning electron microscopy results for lithium silicate glass fibers clearly demonstrate that the crystallization temperature decreased by more than 150 °C when the glass fibers were subjected to a bending stress confirming that a bending stress on a glass fiber enhances its overall tendency for crystallization.
Translation Representations and Scattering by Two Intervals

Studying unitary one-parameter groups in Hilbert space (U(t),H), we show that a model for obstacle scattering can be built, up to unitary equivalence, with the use of translation representations for L2-functions in the complement of two finite and disjoint intervals. The model encompasses a family of systems (U(t),H). For each, we obtain a detailed spectral representation, and we compute the scattering operator and scattering matrix. We illustrate our results in the Lax-Phillips model where (U(t),H) represents an acoustic wave equation in an exterior domain; and in quantum tunneling for dynamics of quantum states.
Self-monitoring in carbon fiber reinforced mortar by reactance measurement

Self-monitoring in carbon fiber reinforced mortar was demonstrated by AC impedance measurement. The reactance Xs was found to be a more sensitive indicator of strain than the resistance Rs. The fractional increase in Xs was 38 at compressive failure, while the fractional increase in Rs was 23, for mortar with methylcellulose, silica fume and fibers (0.35 vol.%).