cssi/SciSciGPT-SciSciNet huggingface dataset:
Supernovae in Early-Type Galaxies: Directly Connecting Age and Metallicity with Type Ia Luminosity

We have obtained optical spectra of 29 early-type (E/S0) galaxies that hosted Type Ia supernovae (SNe Ia). We have measured absorption-line strengths and compared them to a grid of models to extract the relations between the supernova properties and the luminosity-weighted age/composition of the host galaxies. Such a direct measurement is a marked improvement over existing analyses that tend to rely on general correlations between the properties of stellar populations and morphology. We find a strong correlation suggesting that SNe Ia in galaxies whose populationshaveacharacteristic agegreaterthan5Gyrare � 1magfainter atVmax thanthose foundingalaxies withyounger populations. We find that SN Ia distance residuals in the Hubble diagram are correlated with host-galaxy metal abundance with higher iron abundance galaxies hosting less-luminous supernovae. We thus conclude that the time since progenitor formation primarily determines the radioactive Ni production while progenitor metal abundance has a weaker influence on peak luminosity, but one not fully corrected by light-curve shape and color fitters. This result, particularlythesecondarydependenceonmetallicity,hassignificantimplicationsforthedeterminationof theequationof-stateparameter,w ¼ P/( � c 2 ), and could impactplanningfor future dark-energymissionssuchas JDEM. Assuming no selection effects in discovering SNe Ia in local early-type galaxies, we find a higher specific SN Ia rate in E/S0 galaxies with ages below 3 Gyr than in older hosts. The higher rate and brighter luminosities seen in the youngest E/S0 hosts may be a result of recent star formation and represents a tail of the ‘‘prompt’’ SN Ia progenitors. Subject headingg cosmology: observations — galaxies: elliptical and lenticular, cD — galaxies: fundamental parameters — supernovae: general
Discriminatory consequences of non-discriminatory standards

This paper shows that environmental, labour and other standards can be effective strategic policy instruments even when they are strictly non-discriminatory. This is because standards can be set which the foreign producer optimally chooses not to meet, allowing the domestic producer to monopolize the standardized segment of the market. Thus, it is important for policy to consider how much scope there should be for the imposition of unilaterally determined standards - which could impact negatively on trading partners even when they are non-discriminatory-rather than internationally negotiated standards.
Coarsening in the presence of vacancies

Abstract Using Monte Carlo simulations, we explore the effect of vacancy-mediated diffusion on the kinetics of coarsening of a two-phase (matrix and precipitate) alloy system. When a vacancy diffuses into the vicinity of a minority-phase (precipitate) cluster, the further time development of its trajectory is dictated by the interplay of the cluster–matrix interface energy and the thermal fluctuations. For low temperatures, the vacancy takes a position at the interface; while with increasing temperatures, thermal fluctuations favor a random location of the vacancy. Thus, at low temperatures, the probability is relatively higher for minority-phase atoms that evaporate from a cluster, aided by a vacancy, to recondense onto the same cluster, deforming the shapes of the clusters. The consequent shift in the center of mass causes random motion of clusters as a whole. This gives rise to coarsening via cluster–cluster aggregation (CCA) as the clusters encounter one another. As thermal fluctuations increase, the tendency of an atom to diffuse far from the original cluster, aided by a vacancy, increases. Thus, with increasing temperature, the coarsening mechanism gradually changes to Ostwald ripening (OR). At the early stages of coarsening, for sufficiently low temperature and sufficiently high minority-phase concentration, there is a third process, which is a variant of CCA. At sufficiently low minority-phase cluster spacing, the vacancy interfacial diffusion, and the consequent particle reshaping, leads to CCA without the need for any further diffusive motion of the minority-phase clusters. As we describe in detail, this leads to a more complicated time evolution than in the lower concentration and/or higher temperature regime. We include this discussion as part of our overall detailed discussion of the time evolution of the length-scale in coarsening.
Phenomenology of the top mass in realistic extended technicolor models

Abstract Extended technicolor (ETC) theories typically require ETC gauge bosons lighter than of order 1 TeV, to perturbatively generate the t quark mass. We point out that explicit models of t − b mass splitting also typically contain additional TeV scale ETC gauge bosons transforming in the adjoint of technicolor, leading to large weak-isospin-breaking effects observable in the ϱ parameter. Viable ETC models may thus require a lowest ETC scale of order 10 TeV, with relatively strong and finely tuned couplings to generate m t . Such models do not generate observable corrections to the Zb b vertex.
Crystal structure of the HT-Al3Co phase

Abstract The crystal structure of a high temperature (HT) Al3Co phase, which is isostructural to the Al13Os4 phase, was determined by means of single-crystal X-ray diffraction: space group C2/m (No. 12), a = 16.989(4) A, b = 4.098(1) A, c = 7.478(2) A, β = 115.812(5)°, V = 467.9(2) A3, Dc = 3.998 g cm−3, λ(Mo Kα) = 0.71073 A, F(0 0 0) = 532, Mr = 140.81, μ = 8.044 mm−1, Z = 8, R = 0.068 for 373 reflections with I > 2 σ(I), w R 2 = 0.182 for 522 unique reflections, Np = 59, S = 1.037. The HT-Al3Co phase is a crystalline approximant of decagonal quasicrystals. Crystalline phases with the composition among Al11Co4–Al13Co4 have been briefly reviewed.
1,2,5-Thiadiazole derivatives are potent and selective ligands at human 5-HT1A receptors.

Abstract Amino acid derivatives of 1,2,5-thiadiazol-3-yl-piperazine related to (+)-WAY-100135 and WAY-100635 are potent 5-HT 1A receptor agonists and antagonists, which have selective affinity for 5-HT 1A receptors versus α 1 and dopamine (D 2 , D 3 , and D 4 ) receptors.
The Indian Public Distribution System as provider of food security: Evidence from child nutrition in Andhra Pradesh

Abstract We study whether a sudden increase of the price of rice supplied by the Indian Public Distribution System in Andhra Pradesh, a large Indian state, had a negative impact on child nutrition. A few months after the price increase, a health survey started to record weight for a large sample of children. The data collection continued for several months, so that children measured later lived for a longer period of time in a less favorable price regime. Using different estimation techniques we find that longer exposure to high prices are not accompanied by worse nutritional status, as measured by weight-for-age.
A Bacterial Mutant Library as a Tool to Study the Attack of a Defensin Peptide

Human defensins are small, cysteine-rich host-defense peptides that contribute to innate immunity.[1] Human Defensin 5 (HD5ox) is a 32-residue α-defensin that is highly expressed in the small intestine and exhibits antimicrobial activity against a variety of bacterial and fungal species. Despite its importance in human health and disease, the mechanisms of action of HD5oxand many other peptides of the defensin family are not completely understood. Defensins are often generalized as membrane-permeabilizing peptides, but antibacterial mechanisms other than membrane disruption have been identified. We established an unbiased genetic screen based on a mutant library of the model organism Escherichia coli K-12 to identify bacterial pathways that modulate HD5ox susceptibility. The screen yielded thirty-one genes that confer hypersensitivity to HD5ox when knocked-out, and included genes responsible for membrane biosynthesis and integrity. These genes were independently confirmed as being important for HD5ox-mediated killing of E. coli. Moreover, the unbiased screen uncovered an interaction between HD5ox and lipopolysaccharide.
Model-independent Primordial Power Spectrum from MAXIMA, BOOMERANG, and DASI Data

A model-independent determination of the primordial power spectrum of matter density fluctuations could uniquely probe physics of the very early universe and provide powerful constraints on inflationary models. We parameterize the primordial power spectrum A(k) as an arbitrary function and deduce its binned amplitude from the cosmic microwave background (CMB) radiation anisotropy measurements of MAXIMA, BOOMERANG, and DASI. We find that for a flat universe with A(k) = 1 (scale-invariant) for scales k < 0.001 h Mpc-1, the primordial power spectrum is marginally consistent with a scale-invariant Harrison-Zeldovich spectrum. However, we deduce a rise in power compared to a scale-invariant power spectrum for 0.001 h Mpc-1 k 0.01 h Mpc-1. Our results are consistent with large-scale structure data and seem to suggest that the current observational data allow for the possibility of unusual physics in the very early universe.
A randomized trial of cerclage vs. 17 α-hydroxyprogesterone caproate for treatment of short cervix

Objective: To determine pregnancy outcome in patients with short cervix on transvaginal ultrasound between 16 and 24 weeks’ gestation treated with McDonald cerclage compared to weekly intramuscular injections of 17 ahydroxyprogesterone caproate (17OHP-C). Methods: From November 2003 through December 2006, asymptomatic, singleton pregnancies were screened with transvaginal ultrasound between 16–24 weeks’ gestation. Patients with a cervical length (CL) F25 mm were offered enrollment. Patients were randomly assigned to treatment with McDonald cerclage or weekly intramuscular injections of 17OHP-C. The primary outcome was spontaneous preterm birth (PTB) prior to 35 weeks’ gestation. Results: Seventy-nine patients met inclusion criteria; 42 were randomly assigned to the cerclage and 37 to 17OHP-C. Spontaneous PTB prior to 35 weeks’ gestation occurred in 16/42 (38.1%) of the cerclage group and in 16/37 (43.2%) of the 17OHP-C group (relative risk, 1.14 95% CI, 0.67, 1.93). A post hoc analysis of patients with a prior PTB showed no difference in spontaneous PTB -35 weeks between groups. A similar analysis of patients with a CLF15 mm showed a reduction in spontaneous PTB -35 weeks in the cerclage group (relative risk 0.48, 0.24–0.97).
The Descent of Darwin

Noel Castree (2009) regrets that academic geographers let pass without much fuss, the sesquicentenary of the publication of Charles Darwin's The Origin of Species. In part, this is the voice of Madison Avenue admonishing the sales team for missing a glorious promotional opportunity: `buy evolution, get geography free'. Castree has also a more serious point to make in remarking that Darwin used geographical reasoning to fundamentally alter the way people think about human life on earth. These issues still matter and Castree implies that the neglect of Darwin is part of geography's more general failure to engage critically with the sort of big-picture views of life on earth that could gain the discipline the popular attention it deserves.
Localization and routing in sensor networks by local angle information

Location information is useful both for network organization and for sensor data integrity. In this article, we study the anchor-free 2D localization problem by using local angle measurements. We prove that given a unit disk graph and the angles between adjacent edges, it is NP-hard to find a valid embedding in the plane such that neighboring nodes are within distance 1 from each other and non-neighboring nodes are at least distance √2/2 away. Despite the negative results, however, we can find a planar spanner of a unit disk graph by using only local angles. The planar spanner can be used to generate a set of virtual coordinates that enable efficient and local routing schemes such as geographical routing or approximate shortest path routing. We also proposed a practical anchor-free embedding scheme by solving a linear program. We show by simulation that it gives both a good local embedding, with neighboring nodes embedded close and non-neighboring nodes far away, and a satisfactory global view such that geographical routing and approximate shortest path routing on the embedded graph are almost identical to those on the original (true) embedding.
1-Benzenesulfonyl-2-trimethylsilylacetylene: a new acetylene equivalent for the Diels–Alder reaction

1-Benzenesulfonyl-2-trimethylsilylacetylene has been shown to be an effective acetylene equivalent for the Diels–Alder reaction.
Origin of cosmic rays

Based on recent observations of the galactic gas and gamma ray distributions, the galactic cosmic ray distribution is deduced. This distribution is identical to that of supernova remnants (within experimental error), strongly supporting the hypothesis that most observed cosmic rays are produced by supernovas in our own galaxy. The average age of the cosmic ray sources is suggested, from the character of their distribution, to be about 30 million years.
Flexible camera calibration using a new analytical radial undistortion formula with application to mobile robot localization

Most algorithms in 3D computer vision rely on the pinhole camera model because of its simplicity, whereas virtually all imaging devices introduce a certain amount of nonlinear distortion, where the radial distortion is the most severe part. Common approach to radial distortion is by the means of polynomial approximation, which introduces distortion-specific parameters into the camera model and requires estimation of these distortion parameters. The task of estimating radial distortion is to find a radial distortion model that allows easy undistortion as well as satisfactory accuracy. This paper presents a new radial distortion model with an easy analytical undistortion formula, which also belongs to the polynomial approximation category. Experimental results are presented to show that with this radial distortion model, satisfactory accuracy is achieved. An application of the new radial distortion model is non-iterative yellow line alignment with a calibrated camera on ODIS, a robot built in our CSOIS.
Influence of a strong longitudinal static electric field on free carrier faraday effect in an n-type InSb at room temperature at submillimeter wave frequencies

The expression for free carrier Faraday rotation θ and for ellipticity Δ, as the function of the applied parallel static electric field $$\mathop {E_0 }\limits_ \to $$ and static magnetic field $$\mathop {B_0 }\limits_ \to $$ for a given value of wave angular frequency and electron concentration N0, are obtained and theoretically analyzed with the aid of one-dimensional linearized wave theory and Kane's non-parabolic isotropic dispersion law. It is shown that the maximum Faraday rotation occurs near the cyclotron resonance condition, which can be expressed as $$\chi \omega = \omega _{ce} $$ , where $$\chi = 1{1 \mathord{\left/ {\vphantom {1 {\sqrt {1 - ({{v_0 } \mathord{\left/ {\vphantom {{v_0 } {v_c }}} \right. \kern-\nulldelimiterspace} {v_c }})^2 } }}} \right. \kern-\nulldelimiterspace} {\sqrt {1 - ({{v_0 } \mathord{\left/ {\vphantom {{v_0 } {v_c }}} \right. \kern-\nulldelimiterspace} {v_c }})^2 } }}$$ , $$v_c = \sqrt {{{\varepsilon _g } \mathord{\left/ {\vphantom {{\varepsilon _g } {2m}}} \right. \kern-\nulldelimiterspace} {2m}}} *$$ , and $$\omega _{ce} = ({{eB_0 } \mathord{\left/ {\vphantom {{eB_0 } {m*}}} \right. \kern-\nulldelimiterspace} {m*}})$$ . Here m* and e denote the effective mass and charge of electron, respectively. ɛg is the forbidden bandgap of semiconductor. v0 is the carrier drift velocity, which is a non-linear function of E0 in high field condition. A possibility of a simple way of determining the non-linear “v0 vs E0” characteristics of semiconductors by the measurement of Faraday rotation is also discussed.
Production and inventory policies for an integrated manufacturing firm

The coordination of production and inventory decisions for raw materials, intermediate products and finished goods is important. We compare some decision rules for a ‘firm that uses a single raw material to manufacture n different parts which are then assembled into the final product. Demand for the final product is probabilistic and there are costs of holding inventory and of ordering, manufacture and assembly. These characteristics are an idealization of the problem faced by a manufacturer of scaffolds in which the major processes are the manufacture of different sheet metal parts and their assembly. We develop production rules that use system-wide information. We use simulation to evaluate the performance of these rules and compare system behaviour to that under production rules that are derived separately for each item and use only local information about that item's status.
An algebraic criterion for the onset of chaos in nonlinear dynamical systems

On considere des conditions necessaires et suffisantes pour l'existence d'un point dans l'espace parametre definissant l'etablissement d'un regime chaotique dans un systeme dynamique donne
Nonparametric Identification and Semiparametric Estimation of Classical Measurement Error Models Without Side Information

Virtually all methods aimed at correcting for covariate measurement error in regressions rely on some form of additional information (e.g., validation data, known error distributions, repeated measurements, or instruments). In contrast, we establish that the fully nonparametric classical errors-in-variables model is identifiable from data on the regressor and the dependent variable alone, unless the model takes a very specific parametric form. This parametric family includes (but is not limited to) the linear specification with normally distributed variables as a well-known special case. This result relies on standard primitive regularity conditions taking the form of smoothness constraints and nonvanishing characteristic functions’ assumptions. Our approach can handle both monotone and nonmonotone specifications, provided the latter oscillate a finite number of times. Given that the very specific unidentified parametric functional form is arguably the exception rather than the rule, this identification r...
A note on transition, turbulent length scales and transport in differentially rotating flows

In this note we address the issue of hydrodynamical instabilities in Astrophysical rotating shear flows in the light of recent publications focused on the possibility for differential rotation to trigger and sustain turbulence in the absence of a magnetic field. We wish to present in a synthetic form the major arguments in favor of this thesis along with a simple schematic scenario of the transition to and self-sustenance of such turbulence. We also propose that the turbulent diffusion length scale scales as the local Rossby number of the mean flow. A new prescription for the turbulent viscosity is introduced. This viscosity reduces to the so-called β-prescription in the case of velocity profiles with a constant Rossby number, which includes Keplerian rotating flows.
Occupational Aspirations and the Gender Gap in Wages

Focusing on the role of occupational segregation in maintaining gender stratification, this article analyses occupational aspirations and attainment among West Germans born between 1919 and 1971. Male and female life course patterns have strongly converged among younger cohorts, but men and women are still extremely segregated in the labour market, and earn unequal wages. Women are less likely than men to realize their occupational aspirations and their occupational choices are greatly constrained by a gendered system of vocational professional training. However, the allocation of women and men into different occupations is not the primary factor in the gender wage gap. The contribution of occupational gender segregation declined over time and was negligible for younger women. Increasingly across cohorts, the gender wage gap is driven by within-occupation stratification. We show that for the youngest cohort, gender differences in human capital, family obligations, and work life characteristics do not account for within-occupation gender inequality in the late 1990s. While young German women acquired the same, or better, human capital than men, the return to their skills in the labour market has fallen below that of their male contemporaries. We discuss the implications for the stability of gender segregation and policies aimed at alleviating gender inequality.
STAR FORMATION HISTORIES OF NEARBY ELLIPTICAL GALAXIES. II. MERGER REMNANT SAMPLE

This work presents high signal-to-noise spectroscopic observations of a sample of six suspected merger remnants, selected primarily on the basis of H I tidal debris detections. Single stellar population analysis of these galaxies indicates that their ages, metallicities, and α-enhancement ratios are consistent with those of a representative sample of nearby elliptical galaxies. The expected stellar population of a recent merger remnant, a young age combined with low [α/Fe], is not seen in any H I-selected galaxy. However, one galaxy (NGC 2534) is found to deviate from the Z-plane in the sense expected for a merger remnant. Another galaxy (NGC 7332), selected by other criteria, best matches the merger remnant expectations.
A ROSAT Survey of Contact Binary Stars

Contact binary stars are common variable stars that are all believed to emit relatively large fluxes of X-rays. In this work we combine a large new sample of contact binary stars derived from the ROTSE-I telescope with X-ray data from the ROSAT All Sky Survey (RASS) to estimate the X-ray volume emissivity of contact binary stars in the Galaxy. We obtained X-ray fluxes for 140 contact binaries from the RASS, as well as two additional stars observed by the XMM-Newton observatory. From these data we confirm the emission of X-rays from all contact binary systems, with typical luminosities of approximately 1.0 × 1030 ergs s-1. Combining calculated luminosities with an estimated contact binary space density, we find that contact binaries do not have strong enough X-ray emission to account for a significant portion of the Galactic X-ray background.
Probabilistic Asynchronous pi-Calculus

We propose an extension of the asynchronous π-calculus with a notion of random choice. We define an operational semantics which distinguishes between probabilistic choice, made internally by the process, and nondeterministic choice, made externally by an adversary scheduler. This distinction will allow us to reason about the probabilistic correctness of algorithms under certain schedulers. We show that in this language we can solve the electoral problem, which was proved not possible in the asynchronous π-calculus. Finally, we show an implementation of the probabilistic asynchronous π-calculus in a Java-like language.
Modeling global structural damping in trusses using simple continuum models

Truss beams with members having viscous damping are modeled as continuum Timoshenko beams. Procedures for deriving the equivalent beam stiffnesses and damping are presented. The global damping for the continuum beam is explicitly expressed in terms of the damping coefficients of the individual truss members. The continuum beam model is used to study transient vibration problems and the solutions are compared well with the full scale finite element solutions. The gradient method is used for parameter estimations in conjunction with the Timoshenko beam model. It is shown that the Timoshenko beam model can be easily updated with measured data and the updated model can yield very accurate transient solutions.
Thalassemia: The Continued Challenge

This overview describes the history of transfusion therapy and consequent iron overload in thalassemia. It emphasizes the importance of measurement of hepatic iron and reviews the history of chelation therapy. It briefly describes the discoveries of the genetic basis of thalassemia and the application of that knowledge in prenatal diagnosis. The review goes on to emphasize pharmaceutical efforts to induce fetal hemoglobin synthesis in thalassemic red cells and ends with a discussion of oral iron chelators, stem cell transplant, and the status of gene therapy.
Mechanisms for the Intracellular Manipulation of Organelles by Conventional Electroporation

Conventional electroporation (EP) changes both the conductance and molecular permeability of the plasma membrane (PM) of cells and is a standard method for delivering both biologically active and probe molecules of a wide range of sizes into cells. However, the underlying mechanisms at the molecular and cellular levels remain controversial. Here we introduce a mathematical cell model that contains representative organelles (nucleus, endoplasmic reticulum, mitochondria) and includes a dynamic EP model, which describes formation, expansion, contraction, and destruction for the plasma and all organelle membranes. We show that conventional EP provides transient electrical pathways into the cell, sufficient to create significant intracellular fields. This emerging intracellular electrical field is a secondary effect due to EP and can cause transmembrane voltages at the organelles, which are large enough and long enough to gate organelle channels, and even sufficient, at some field strengths, for the poration of organelle membranes. This suggests an alternative to nanosecond pulsed electric fields for intracellular manipulations.
Ornate necklaces and the homology of the genus one mapping class group

AbstractAccording to seminal work of Kontsevich, the unstable homology of the mapping class group of a surface can be computed via the homology of a certain Lie algebra. In a recent paper, S. Morita analyzed the abelianization of this Lie algebra, thereby constructing a series of candidates for unstable classes in the homology of the mapping class group. In the current paper, we show that these cycles are all nontrivial, representing homology classes in Hk(M1kQ)Sk for all k ≥ 5 satisfying k ≡ 1 mod 4. Here M1k is the mapping class group of a genus one surface with k punctures.
Labor productivity during the Great Depression

Abstract During the 1929–1933 contraction, labor productivity was countercyclical in several manufacturing sectors- evidence consistent with the view that large negative demand shocks pushed the economy down a static, neoclassical production function. This evidence does not readily square with explanations for the contraction emphasizing labor hoarding and increasing returns.
Measuring and Analyzing Sovereign Risk with Contingent Claims

This paper develops a comprehensive new framework to measure and analyze sovereign risk. Contingent claims analysis is used to construct a marked-to-market balance sheet for the sovereign and derive a set of forward-looking credit risk indicators that serve as a barometer of sovereign risk. Applications to 12 emerging market economies show the approach to be robust, and the risk indicators are a significant improvement over traditional macroeconomic vulnerability indicators and accounting-based measures. The framework can help policymakers design risk mitigation strategies and rank policy options using a calibrated structural model unique to each economy.
A convenient route to 1,3-cyclooctatetraenophanes

Abstract Three cyclooctatetraenes, bridged with methylene groups in a previously unknown 1,3-manner, have been prepared in racemic form by a route involving ultimate disrotatory opening of a suitably constructed bicyclo[4.2.0]octatriene precursor.
Unsteady flow about porous cambered shells

A numerical simulation was carried out through the use of the vortex-element methods to investigate the characteristics of an impulsively started uniform flow, decelerating at prescribed rates about a two-dimensional cambered porous shell, with an included angle of 120 deg, for the purpose of understanding the effects of porosity on the conditions under which wake recontact occurs
Temperature spectra in shear flow and thermal convection

We show that the Pu(small omega, Greek) proportional to small omega, Greek?7/3 shear velocity power spectrum gives rise to a P?(small omega, Greek) proportional to small omega, Greek ?4/3 power spectrum for a passively advected scalar, as measured in experiment [K. Sreenivasan, Proc. R. Soc. A 434 (1991) 165]. Applying our argument to high Rayleigh number Rayleigh-Benard flow, we can account for the measured scaling exponents equally well as the Bolgiano-Obukhov theory (BO59). Yet, of the two explanations, only the shear approach might be able to explain why no classical scaling range is seen in between the shear (or BO59) range and the viscous subrange of the experimental temperature spectrum
APPLYING THE ANALYTIC HIERARCHY PROCESS TO OIL SANDS ENVIRONMENTAL COMPLIANCE RISK MANAGEMENT

In 2013, oil companies in Alberta, Canada invested $32 billion in new oil-sands projects.Â Despite the size of this investment, there is a demonstrable deficiency in the uniformity and understanding of environmental legislation requirements that translate into increased project compliance risks. In this paper, we applied the Analytic Hierarchy Process (AHP) to develop a priority list of environmental regulatory compliance risk criteria for oil-sands projects.Â AHP belongs to the family of multicriteria decision-making (MCDM) techniques that utilizes a pairwise comparison matrix solicited from subject matter experts (SMEs) in the field as input.Â The overall methodology itself consisted of 4 phases: (1) identification of the initial list of N potential environmental compliance risk criteria and verification of these criteria via a pilot survey; (2) formation of a pairwise comparison survey in the form of an N(N-1)/2 comparison matrix based on the verified criteria; (3) administration of the pairwise comparison matrix to a sample of 16 industry-specific SMEâ€™s; and (4) the application of the AHP method using SuperDecisions as a tool on the collected sample to rank the identified risk criteria. Our demonstrated results can potentially inform Alberta oil sands industry leaders about the ranking and utility of specific compliance risks as understood by experts and enable a more focused environmental compliance action to help increase legislative and public trust.
Abrupt transitions and hysteresis in thermohaline laboratory models

As a driving parameter is slowly altered, thermohaline ocean circulation models show either a smooth evolution of a mode of flow or an abrupt transition of temperature and salinity fields from one mode to another. An abrupt transition might occur at one value or over a range of the driving parameter. The latter has hysteresis because the mode in this range depends on the history of the driving parameter. Although assorted ocean circulation models exhibit abrupt transitions, such transitions have not been directly observed in the ocean. Therefore, laboratory experiments have been conducted to seek and observe actual (physical) abrupt thermohaline transitions. An experiment closely duplicating Stommel’s box model possessed abrupt transitions in temperature and salinity with distinct hysteresis. Two subsequent experiments with more latitude for internal circulation in the containers possessed abrupt transitions over a much smaller range of hysteresis. Therefore, a new experiment with even more latitude for internal circulation was designed and conducted. A large tank of constantly renewed freshwater at room temperature had a smaller cavity in the bottom heated from below with saltwater steadily pumped in. The cavity had either a salt mode, consisting of the cavity filled with heated salty water with an interface at the cavity top, or a temperature mode, in which the heat and saltwater were removed from the cavity by convection. There was no measurable hysteresis between the two modes. Possible reasons for such small hysteresis are discussed.
The real “Total Cost of Ownership” of your test equipment

Cost of ownership is always a hot topic when making a program decision for any new, upgrade, or sustainment option. The criteria for developing a Total Cost of Ownership (TCO) model quickly turns into debates with many facets and lots of emotion. When it comes to the cost of acquiring and operating test equipment, the answer is not any easier to determine. However, if looked at from a Product Life Cycle (PLC) cost or a Performance-Based Logistic (PBL) view point, a more accurate cost model can be developed. By understanding and using the attributes of direct and indirect costs for acquiring, operating, maintaining, migrating, and disposing of these assets, an accurate model of the total cost of ownership can be obtained. This will lay out the PLC/PBL costs of test equipment and walk through a TCO model that can be used for making trade-off decisions between different program options.
Linnaeus’ study of Swedish swidden cultivation: Pioneering ethnographic work on the ‘economy of nature’

Carl Linnaeus’ work on the ‘economy of nature’ was a major early development in what became the modern field of ecology. This analysis suggests that a key subject of this work that has been ignored or misunderstood for 250 years is the rural livelihoods, especially swidden (or slash-and-burn) agriculture, which Linnaeus studied during his expeditions through rural Sweden. Rereading his reports in the light of modern work on swiddens, political ecology, and the history of science affords a new appreciation of Linnaeus’ insights into traditional systems of resource exploitation. The logic of nutrient cycling in swidden agriculture and its utilization of natural dynamics to serve human ends exemplify the principles of the ‘economy of nature’, and gave Linnaeus a philosophical basis for understanding and defending this system of agriculture as well as other rural resource use systems in Sweden. This analysis sheds new light on Linnaeus’ ethnographic work, his view of folk environmental knowledge, and his often derided identification with Sweden’s ethnic peoples.
Assisted reproduction technologies impair placental steroid metabolism.

The placenta plays a vital role in pregnancy by facilitating steroid passage from maternal to fetal circulation and/or direct production of hormones. Using a murine model, we demonstrated the differences in placental steroid metabolism between pregnancies conceived naturally and with assisted reproduction technologies (ART): in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). While the ovarian steroid production was similar (estrone, 17β-estradiol) or higher (estriol) in ART pregnancies compared to mating, the levels of placental estriol were significantly lower in ART group. Placentas from ART had significantly higher activities of the steroid metabolizing enzymes UDP-glucuronosyltransferase (UGT) and sulfotransferase (SULT), which in ICSI were also coupled with decreased activity of the steroid regenerating enzymes β-glucuronidase (β-G) and aryl sulfatase (AS). Levels of steroid metabolites androstane-3α-17β-diol glucuronide and dehydroepiandrosterone sulfate were higher in fetal compared to maternal blood in ART, but not in mating. This study demonstrates that in murine ART pregnancies, higher metabolism and clearance of steroids by the placenta may seriously affect the passage of essential hormones to the fetus. If a similar phenomenon exists in humans, this could provide a plausible explanation for obstetric and neonatal complications associated with ART, including the higher incidence of low birth weight babies.
Structure and characterization of sol–gel and aerogel materials and oxidation products from the reaction of (CH3O)4Si and C16H33Si(OCH3)3

Abstract The hexadecyl substituted siloxane, C16H33Si(OCH3)3, was reacted with (CH3O)4Si at the mole ratio of 1–3 in methanol using HBF4 catalysis. Sol–gel materials were formed that have low surface areas (∼10 m2/g). Subsequent supercritical drying using CO2 at 40 °C produced materials that are very different than traditional aerogels, with surface areas around the same values as the corresponding sol–gels, as well as no detectable meso-pore features. In some cases, the aerogels even melted upon heating. Spectroscopic characterization, using IR, 29Si and 13C NMR revealed normal Si–O substitution as well as incorporation of the carbon substituent into the Si framework. Heating of the stable forms of the materials in air at different temperatures yielded, depending upon oxidation conditions, several materials with much higher surface areas, typical of aerogels. Pore size distribution measurements revealed meso-pore features with a narrow distribution of 37–39 A. Spectroscopic characterization revealed the disappearance of the R-Si substitution and the appearance of an oxidized intermediate. This paper describes the chemistry and characterization of these unusual sol–gels, aerogels, and oxidation products.
Origin of the Soft Excess in X-Ray Pulsars

The spectra of many X-ray pulsars show, in addition to a power law, a low-energy component that has often been modeled as a blackbody with kTBB ~ 0.1 keV. However, the physical origin of this soft excess has remained a mystery. We examine a sample of well-studied bright X-ray pulsars, which have been observed using ROSAT, ASCA, Ginga, RXTE, BeppoSAX, Chandra, and XMM-Newton. In particular, we consider the Magellanic Cloud pulsars SMC X-1, LMC X-4, XTE J0111.2-7317, and RX J0059.2-7138 and the Galactic sources Her X-1, 4U 1626-67, Cen X-3, and Vela X-1. We show that the soft excess is a very common if not ubiquitous feature intrinsic to X-ray pulsars. We evaluate several possible mechanisms for the soft emission, using theoretical arguments, as well as observational clues, such as spectral shapes, eclipses, pulsations of the soft component, and superorbital modulation of the source flux. We find that reprocessing of hard X-rays from the neutron star by the inner region of the accretion disk is the only process that can explain the soft excess in all the pulsars with LX 1038 ergs s-1. Other mechanisms, such as emission from diffuse gas in the system, are important in less luminous objects.
Essentially perturbative quantities in the Kondo model

It is shown that in the Kondo model the crossover between strong-and weak-coupling regimes is essentially perturbative in nature. Specifically, the impurity's contribution to the zero-temperature magnetization, μ i ( H ), can be reconstructed from a knowledge of its perturbation series, via Borel summation. The asymptotic behavior of μ i ( H ) for vanishing magnetic field, together with a known result of second-order perturbation theory at nonzero temperature, gives Wilson's ratio of dimensional scales without resorting to nonperturbative techniques.
A simple synthesis of 10-deacetoxytaxol derivatives

Abstract The C-10 oxygen substituent can be reductively removed in high yield by reaction of taxol, baccatin III, or 10-deacetylbaccatin III with samarium diiodide. This reaction pathway can be completely shut down by protection of the C-7 hydroxyl group of baccatin III as the triethylsilyl ether.
Breakdown of macroscopic quantum self-trapping in coupled mesoscopic one-dimensional Bose gases

Two coupled Bose-Einstein condensates with a large population imbalance exhibit macroscopic quantum self-trapping (MQST) if the ratio of interaction energy to tunneling energy is above a critical value. Here we investigate effect of quantum fluctuations on MQST. In particular, we analyze the dynamics of a system of two elongated Bose gases prepared with a large population imbalance, where due to the quasi-one-dimensional character of the gas we no longer have true long range order, and the effect of quantum fluctuations is much more important. We show that MQST is possible in this system, but even when it is achieved it is not always dynamically stable. Using this instability one can construct states with sharply peaked momentum distributions around characteristic momenta dependent on system parameters. Our other finding is the nonmonotonic oscillating dependence of the decay rate of the MQST on the length of the wires. We also address the interesting question of thermalization in this system and show that it occurs only in sufficiently long wires.
Large eddy simulation of a nonpremixed reacting jet: Application and assessment of subgrid-scale combustion models

Results from large eddy simulations (LES) and direct numerical simulations (DNS) of a two-dimensional, spatially developing, compressible planar free jet undergoing an idealized, exothermic, chemical reaction of the type F+rOx→(1+r)P are presented in order to assess several subgrid-scale (SGS) combustion models. Both a priori and a posteriori assessments are conducted. The SGS turbulence model used is the dynamic Smagorinsky model (DSM). Two classes of SGS combustion models are employed in this study. These include the conserved scalar approach and the direct closure approach. Specifically, the SGS combustion models involve several forms of direct filtered reaction rate closures, including a scale similarity filtered reaction rate model (SSFRRM), and a mixing controlled strained laminar flamelet model (SLFM) in the form of thermochemical state relationships, obtained from the DNS, and two assumed forms for the subgrid mixture fraction filtered density function (FDF). In general, LES results are in reasonable agreement with DNS results and highlight the performance of the various SGS combustion models. In particular, in the context of the present study, it is found that: (1) the SLFM cases overpredict product formation due to their inability to capture finite-rate chemistry effects; (2) due to the relatively low values of the SGS mixture fraction variance in the flow under study, the SLFM results are not sensitive to the form of the assumed FDF; and (3) in comparison to the other models investigated, the SSFRRM combustion model provides the best agreement with the DNS for product formation.
An Anionic Rhodium η4-Quinonoid Complex as a Multifunctional Catalyst for the Arylation of Aldehydes with Arylboronic Acids

The π-bonded rhodium quinonoid complex, K+[(1,4-benzoquinone)Rh(COD)]-, functions as a good catalyst for the coupling of arylboronic acid and aldehydes to afford diaryl alcohols. The catalysis is heterobimetallic in that both the transition metal and concomitant alkali metal counterion play an integral part in the reaction. In addition, the anionic quinonoid catalyst itself plays a bifunctional role by acting as a ligand to the boronic acid and as a Lewis acid receptor site for the transferring aryl group.
Dynamic Reservoir Data Assimilation With an Efficient, Dimension-Reduced Kalman Filter

Kalman filter-based methods have been widely applied for assimilating new measurements to continuously update the estimate of state variables, such as reservoir properties and responses. The standard Kalman filtering scheme requires computing and storing the covariance matrix of state variables, which is computationally expensive for large-scale problems with millions of gridblocks. In the ensemble Kalman filter (EnKF), this problem is alleviated with sampling from a limited number of realizations and computing the required subset of the covariance matrix at each update. However, the goodness of the (ensemble) covariance approximated from the limited ensemble depends on the number of realizations used and the representativity of a given ensemble. In this study, we propose an efficient, dimension-reduced Kalman filtering scheme based on Karhunen-Loeve (KL) and other orthogonal polynomial decompositions of the state variables. We consider flow in heterogeneous reservoirs with spatially variable permeability. The reservoir responses such as pressure are measured at some locations at various time intervals. The aim is to dynamically characterize the reservoir properties and to predict the reservoir performance and its uncertainty at future times. In our scheme, the covariance of the reservoir properties is approximated by a small set of eigenvalues and eigenfunctions using the KL decomposition and the reconstruction of the covariance from the KL decomposition can be done whenever needed. In each update, the forecast step is solved using the KL-based moment method, giving a set of functions from which the mean and covariance of the state variables can be constructed, when needed. The statistics of both the reservoir properties and the reservoir responses are then updated with the available measurements at this time using the autoand cross-covariances obtained from the forecast step. The new approach is illustrated on a heterogeneous reservoir with dynamic measurements and the results are compared with those from the EnKF method, in terms of accuracy and efficiency.
In vitro binding of steroid hormones by natural and purified fibers

The in vitro binding of estrone, estradiol-17 beta, estriol, testosterone, dihydrotestosterone, and estrone-3-glucuronide by wheat, oat, and corn brans, oat hulls, cellulose, lignin, and cholestyramine resin was measured. The extent of steroid sequestration was characteristic and reproducible for each hormone. Cholestyramine bound an average of 90% of all the steroids tested, whereas cellulose bound the least (12%). Of the other substances tested, each bound the following percentage of unconjugated hormones: lignin, 87%; wheat and oat brans, 45% each; corn bran 44%; and oat hulls, 32%. The conjugated steroid was less likely to bind than the unconjugated steroids. Lignin appeared to be an important component in the interaction with steroid hormones. The results support the hydrophobic nature of adsorption and suggest that the components of fiber in diet should be considered separately when evaluating in vivo metabolic effects.
Video Display Terminals: Radiation Issues

During the past decade, the use of video display terminals (VDTs) in information processing and related applications has grown exponentially. Recent estimates place the number of terminals in the workplace at more than ten million. Along with this rapid growth there has been a concomitant increase in concern about the radiation emissions from the VDT. Several types of radiation can be emitted by the terminal. Cataracts, reproductive problems, and skin rashes have been reported by VDT operators and are alleged to result from radiation exposure. However, measurements of the radiation emissions, when compared to the present occupational exposure standards, lead to the conclusion that the terminal does not present a radiation hazard to the VDT operator.
Contract Renegotiation and Coasian Dynamics

Consider a long-term relationship between a seller and a buyer whose valuation (for a per-period service or a durable good) is private. As trade progresses, the valuation will be partially revealed, and it may be impossible for the parties to commit ex-ante not to take advantage of this. We analyse this situation first by supposing that the parties can sign a sequence of short-term contracts; and secondly by supposing that they can sign a long-term contract, but cannot commit not to renegotiate it later. We find a close relationship in the second case between the optimal long-term contract and the non-commitment outcome in the standard Coasian durable good model. Our results also have implications for hidden-information principal-agent models.
String orthogonal polynomials, string equations, and 2 Toda symmetries

1. The 2-Toda lattice and its generic symmetries 2. A Larger class of symmetries for special initial conditions 3. Borel decomposition of Moment matrices, tau-functions and string-orthogonal polynomials 4. From string-orthogonal Polynomials to the 2-Toda lattice and the string equation 5. Virasoro constraints on two-matrix integrals Comment: 45 pages, Latex