cssi/SciSciGPT-SciSciNet huggingface dataset:
An Accreting Blackhole Model for SGR A

The presence of a strong circumnuclear wind (with velocity νgw ≈ 500– 700 km s-1 and mass-loss rate ≈ 3 — 4 × 10-3 M ⊙ yr-1) in the vicinity of IRS 16 and Sgr A* is suggested by the observation of broad He I, Brα, and Brγ emission lines from this region. Sgr A* may be accreting a portion of this wind incident within the massdependent accretion radius 2GM/υ 2 gw, corresponding to ≈ 1 × 1022(M/106 M ⊙)2 g s-1 for the observed conditions in the nucleus. We here summarize the results of detailed calculations for the physical state of the infalling plasma and the corresponding spectrum derived from bremsstrahlung and magnetic bremsstrahlung emission from this gas as it descends toward the event horizon. The spectrum is tightly constrained across more than 12 decades in frequency, and the most likely value of the mass inferred from this modelling appears to he in the range ≈ 1 – 2 × 106 M ⊙. In addition, it appears that a slight excess of angular momentum in the accreting gas may be necessary in order to account for the IR luminosity from this source. We present some preliminary results of ongoing multidimensional hydrodynamic simulations that suggest the likely origin of this excess and the intensity fluctuations observed at radio wavelengths.
Temporal versus stochastic granularity in thermal generation capacity planning with wind power

We propose a stochastic generation expansion model, where we represent the long-term uncertainty in the availability and variability in the weekly wind pattern with multiple scenarios. Scenario reduction is conducted to select a representative set of scenarios for the long-term wind power uncertainty. We assume that the short-term wind forecast error induces an additional amount of operating reserves as a predefined fraction of the wind power forecast level. Unit commitment (UC) decisions and constraints for thermal units are incorporated into the expansion model to better capture the impact of wind variability on the operation of the system. To reduce computational complexity, we also consider a simplified economic dispatch (ED) based model with ramping constraints as an alternative to the UC formulation. We find that the differences in optimal expansion decisions between the UC and ED formulations are relatively small. We also conclude that the reduced set of scenarios can adequately represent the long-term wind power uncertainty in the expansion problem. The case studies are based on load and wind power data from the state of Illinois.
THERMAL PERFORMANCE OF BUILDINGS AND BUILDING ENVELOPE SYSTEMS: AN ANNOTATED BIBLIOGRAPHY

LBL-892 5 c::;. · ) __ >EEB-Env-79-5 Presented at the DOE/ASTM Thermal Insulation Conference, Tampa, Florida, October 23-24, 1978 ird;:: C E PlED k/~WR!;NCE BERIGiiJN lAilORATORY Mi1. Y 1. 8 19/9 LIBRARY AND DOCUiv'IE;NTS .SE:CTIOI\! TWO-WEEK LOAN COPY This is a Library Circulating Copy which may be borrowed for two weeks. For a personal retention copy, call Tech. Info. Division, Ext. 6782 Environment Division Thermal Performance of Buildings and Building Envelope Systems: An Annotated Bibliography William L. Carroll • l April 1979 University of California/Berkeley Prepared for the U.S. Department of Energy under Contract No. W-7405-ENG-48 r tJj t' j' N V\
Limit Cycle Conditions in Optimalizing Controllers

A method is developed for determining search limit cycle frequency and magnitude in single dimensional optimalizing (peak holding) systems. The performance criterion measurement process is modeled by a nonlinear function (often adequately approximated by a parabola) in cascade with a linear filter, denoted G(jω), representing measurement delay. The analysis is based upon a single describing function (DF) of the logic circuitry, the parameter adjustment integrator, and the performance criterion nonlinearity. The DF is frequency dependent, adding some complexity to the standard, although seldom applied, graphical solution method, but the procedure is otherwise straightforward. Limit cycle amplitude and frequency are determined directly from DF and G locus intersection values in the usual way. Prediction accuracy averages approximately 5 percent for the examples considered, and is often even better. As should be expected, greatest predictive accuracy is obtained when considerable smoothing (measurement filtering) is present in the feedback loop. When measurement filtering is negligible, limit cycle conditions are readily obtained by more direct methods.1
Is the Cosmological Constant Non-Zero?

Clearly more data are needed for both the CBR Doppler peak and the high-Z supernovae. Fortunately both are expected in the forseeable future.
Nucleon mass and strange content from (2+1)-flavor Domain Wall Fermion

We report on our ongoing study of nucleon properties, the nucleon mass and the strange quark content (〈N|ss|N〉) in particular. These calculations are done on (2+1)-flavor Domain Wall Fermion (DWF) ensembles with Iwasaki gauge action with 2 different lattice spacings (a ∼ 0.08, 0.11fm) and DWF with Dislocation Suppressing Determinant Ratio (DSDR) (a ∼ 0.14fm), generated by RBC/UKQCD collaborations.
A Complexity-Theoretic Approach to Incremental Computation

We present a new complexity-theoretic approach to incremental computation. We define complexity classes that capture the intuitive notion of incremental efficiency and study their relation to existing complexity classes. We show that all common logs p-complete problems for poly are incrplt-complete for poly. This suggests that non-redundant problems that seem inherently unparallelizable also seem hard to dynamize. We show that a form of transitive closure is complete under incremental reduction for nlgsp and give similar problems which are incrementally complete for the classes logsp and non-uniform nick. We show that under certain restrictions problems which have efficient dynamic solutions also have efficient parallel solutions. We also look at the time complexity of circuit value and network stability problems restricted to comparator gates. We show that the dynamic version of the comparator-circuit value problem and ``Lex-First Maximal Matching'''' problem is in logsp and that of the comparator-network stability problem and ``Man-Optimal Stable Marriage Problem'''' is in logsp given an oracle which operates in nlgsp. This shows that the dynamic versions of these problems are solvable quickly in parallel even though there are no known nick algorithms to solve them from scratch.
Rational Growth and Almost Convexity of Higher-Dimensional Torus Bundles

Given a matrix $A\in SL(N,\Z)$, form the semidirect product $G=\Z^N\rtimes_A \Z$ where the $\Z$ factor acts on $\Z^N$ by $A$. Such a $G$ arises naturally as the fundamental group of an $N$-dimensional torus bundle which fibers over the circle. In this paper we prove that if $A$ has distinct eigenvalues not lying on the unit circle, then there exists a finite index subgroup $H\leq G$ possessing rational growth series for some generating set. In contrast, we show that if $A$ has at least one eigenvalue not lying on the unit circle, then $G$ is not almost convex for any generating set.
Minimum convex partitions and maximum empty polytopes

Let S be a set of n points in R d . A Steiner convex partition is a tiling of conv( S ) with empty convex bodies. For every integer d , we show that S admits a Steiner convex partition with at most ⌈( n -1)/ d ⌉ tiles. This bound is the best possible for points in general position in the plane, and it is the best possible apart from constant factors in every fixed dimension d ≥3. We also give the first constant-factor approximation algorithm for computing a minimum Steiner convex partition of a planar point set in general position. Establishing a tight lower bound for the maximum volume of a tile in a Steiner convex partition of any n points in the unit cube is equivalent to a famous problem of Danzer and Rogers. It is conjectured that the volume of the largest tile is ω(1/ n ). Here we give a (1-\epsilon)-approximation algorithm for computing the maximum volume of an empty convex body amidst n given points in the d -dimensional unit box [0,1] d .
Chandra Detection of an X-Ray Flare from the Brown Dwarf LP 944-20

We have detected a bright X-ray flare from the nearby (d = 5.0 pc) brown dwarf LP 944-20 with the Chandra Advanced CCD Imaging Spectrometer-S. This is an old (500 Myr), rapidly rotating, lithium-bearing M9 object, with a bolometric luminosity of ≈6 × 10^(29) ergs s^(-1). It was detected only by Chandra during an X-ray flare of duration 1-2 hr near the end of a 12.1 hr observation. The peak X-ray luminosity was 1.2^(+0.5)_(-0.3) × 10^(26) ergs s^(-1) in the brightest ≈550 s, corresponding to L_X/L_(bol) ≈ 2 × 10^(-4). A total of 2 × 10^(29) ergs was released during the 43,773 s observation, giving a time-averaged L_X/L_(bol) ≈ 7 × 10^(-6). LP 944-20 was not detected before the flare, with a 3 σ upper limit on the emission at L_X/L_(bol) < 2 × 10^(-6) (L_X < 1 × 10^(24) ergs s^(-1)). This is faint for a rapidly rotating late-type star and establishes a record lower limit to the quiescent flux about an order of magnitude below the flux limit (and a factor of 5 below the L_X/L_(bol) limit) placed on quiescent X-ray emission from the M8 dwarf VB 10. The inferred flaring duty cycle is comparable to that measured via variable Hα emission for other late M-type, fully convective stars.
A Simple Linear Time Algorithm for Finding Even Triangulations of 2-Connected Bipartite Plane Graphs

Recently, Hoffmann and Kriegel proved an important combinatorial theorem [4]: Every 2-connected bipartite plane graph G has a triangulation in which all vertices have even degree (it's called an even triangulation). Combined with a classical Whitney's Theorem, this result implies that every such a graph has a 3-colorable plane triangulation. Using this result, Hoffmann and Kriegel significantly improved the upper bounds of several art gallery and prison guard problems. A complicated O(n2) time algorithm was obtained in [4] for constructing an even triangulation of G. Hoffmann and Kriegel conjectured that there is an O(n3/2) algorithm for solving this problem [4].In this paper, we develop a very simple O(n) time algorithm for solving this problem. Our algorithm is based on thorough study of the structure of all even triangulations of G. We also obtain a simple formula for computing the number of distinct even triangulations of G.
Impressions of the Meson Spectrum: Hybrids & Exotics, present and future

It has long been expected that the spectrum of hadrons in QCD would be far richer and extensive than experiment has so far revealed. While there have been experimental hints of this richness for some time, it is really only in the last few years that dramatic progress has been seen in the exploration both experimentally and in calculations on the lattice. Precision studies enabled by new technology both with detectors and high performance computations are converging on an understanding of the spectrum in strong coupling QCD. These methodologies are laying the foundation for a decade of potential discovery that electro and photoproduction experiments at Jefferson Lab, which when combined with key results on B and charmonium decays from both e+e? and pp colliders, should turn mere impressions of the light meson spectrum into a high definition picture.
Single molecule-level detection and long read-based phasing of epigenetic variations in bacterial methylomes

Beyond its role in host defense, bacterial DNA methylation also plays important roles in the regulation of gene expression, virulence and antibiotic resistance. Bacterial cells in a clonal population can generate epigenetic heterogeneity to increase population-level phenotypic plasticity. Single molecule, real-time (SMRT) sequencing enables the detection of N6-methyladenine and N4-methylcytosine, two major types of DNA modifications comprising the bacterial methylome. However, existing SMRT sequencing-based methods for studying bacterial methylomes rely on a population-level consensus that lacks the single-cell resolution required to observe epigenetic heterogeneity. Here, we present SMALR (single-molecule modification analysis of long reads), a novel framework for single molecule-level detection and phasing of DNA methylation. Using seven bacterial strains, we show that SMALR yields significantly improved resolution and reveals distinct types of epigenetic heterogeneity. SMALR is a powerful new tool that enables de novo detection of epigenetic heterogeneity and empowers investigation of its functions in bacterial populations.
Controlled Flight into Terrain Accidents: System-Induced Errors:

Controlled flight into terrain accidents are those in which an aircraft, under the control of the crew, is flown into terrain (or water) with no prior awareness on the part of the crew of the impen...
On the use of the singular value decomposition for text retrieval

The use of the Singular Value Decomposition (SVD) has been proposed for text retrieval in several recent works. This technique uses the SVD to project very high dimensional document and query vectors into a low dimensional space. In this new space it is hoped that the underlying structure of the collection is revealed thus enhancing retrieval performance. Theoretical results have provided some evidence for this claim and to some extent experiments have confirmed this. However, these studies have mostly used small test collections and simplified document models. In this work we investigate the use of the SVD on large document collections. We show that, if interpreted as a mechanism for representing the terms of the collection, this technique alone is insufficient for dealing with the variability in term occurrence. Section 2 introduces the text retrieval concepts necessary for our work. A short description of our experimental architecture is presented in Section 3. Section 4 describes how term occurrence variability affects the SVD and then shows how the decomposition influences retrieval performance. A possible way of improving SVD-based techniques is presented in Section 5 and concluded in Section 6.
Lewis acid-promoted [2 + 2] cycloadditions of alkenes with aryl ketenes

A method for the [2 + 2] cycloaddition of aryl ketenes and alkenes is presented. The process involves the in situ generation of a ketene in the presence of a Lewis acid. The utility of products is demonstrated towards the synthesis of a common scaffold found in several natural product families.
Simultaneous Approximation of Constraint Satisfaction Problems

Given k collections of 2SAT clauses on the same set of variables V, can we find one assignment that satisfies a large fraction of clauses from each collection? We consider such simultaneous constraint satisfaction problems, and design the first nontrivial approximation algorithms in this context.
High-Order Discontinuous Galerkin Methods by GPU Metaprogramming

Discontinuous Galerkin (DG) methods for the numerical solution of partial differential equations have enjoyed considerable success because they are both flexible and robust: They allow arbitrary unstructured geometries and easy control of accuracy without compromising simulation stability. In a recent publication, we have shown that DG methods also adapt readily to execution on modern, massively parallel graphics processors (GPUs). A number of qualities of the method contribute to this suitability, reaching from locality of reference, through regularity of access patterns, to high arithmetic intensity. In this article, we illuminate a few of the more practical aspects of bringing DG onto a GPU, including the use of a Python-based metaprogramming infrastructure that was created specifically to support DG, but has found many uses across all disciplines of computational science.
The Stability of Low-Rank Matrix Reconstruction: A Constrained Singular Value View

The stability of low-rank matrix reconstruction with respect to noise is investigated in this paper. The $\ell _{\ast}$ -constrained minimal singular value ( $\ell _{\ast}$ -CMSV) of the measurement operator is shown to determine the recovery performance of nuclear norm minimization-based algorithms. Compared with the stability results using the matrix restricted isometry constant, the performance bounds established using $\ell _{\ast}$ -CMSV are more concise, and their derivations are less complex. Isotropic and subgaussian measurement operators are shown to have $\ell _{\ast}$ -CMSVs bounded away from zero with high probability, as long as the number of measurements is relatively large. The $\ell _{\ast}$ -CMSV for correlated Gaussian operators are also analyzed and used to illustrate the advantage of $\ell _{\ast}$ -CMSV compared with the matrix restricted isometry constant. We also provide a fixed point characterization of $\ell _{\ast}$ -CMSV that is potentially useful for its computation.
WTO accession for countries in transition

Countries in transition have considered membership in the World Trade Organization (WTO) an important step toward integration in the international economic system. After several years of negotiations, five members of the former Soviet Union (FSU) - Armenia, the three Baltic countries, and the Kygryz Republic - may become members in 1998. It will probably take longer for Russia, Ukraine, and some others. It takes four to five years to process applications for FSU countries - which is close to average for recent applicants. The five countries expected to accede to the WTO this year are among the more liberal member of the FSU. With those five processed, there will be a backlog of another 26 application, most of them countries in transition, including China and Russia. At the current rate of processing, it will take five to six years to process them - and a decade or more for the 25 or so developing and transition economies that have yet to apply. Processing is tine-consuming because: legislative requirements needed for accession are time-consuming; candidate countries are weak institutionally and unfamiliar with the economic and legal issues to be addressed; the fact finding process is unnecessarily cumbersome and time-consuming; technical assistance to applicants in meeting the requirements for WTO accession is not effectively coordinated; and addressing the commercial interests of all members requires protracted negotiations. Governments seeking accession must coordinate the legislative and regulatory changes needed in their foreign trade regimes, adopt liberal trade policies, and identify areas of institutional weakness that require delays in implementation of WTO provisions and seek agreement on such delays. WTO members, for their part, should expedite the process, as universal membership is in everyone s best interest. They should: agree to suitable, time-bound extensions to allow acceding governments to address institutional weaknesses; provide coordinated assistance to acceding countries to strengthen their institutional capacity; and streamline the fact finding aspects of the accession process and give the WTO secretariat the budgetary resources it needs to work with applicant governments for this purpose.
Fibrin Scaffold as an Effective Vehicle for the Delivery of Acidic Fibroblast Growth Factor (FGF-1):

The effect of wound healing by fibrin and acidic fibroblast growth factor (FGF-1) in an in vivo model was evaluated in this study. Four full-thickness wounds were made on the dorsum of each rabbit ...
Chain Extension of Boronic Esters with Lithiooxiranes Generated by Sulfoxide–Metal Exchange – Stereocontrolled Access to 2°/2°, 2°/3°, and 3°/3° Vicinal Diols and Related Compounds

Lithiooxiranes [LiCR1(O)CR2R3, R1 = H, Me; R2/R3 = H/Ph, H/tBu, Me/Ph], generated by sulfoxide–lithium exchange from stereodefined sulfinyl epoxides (with use of PhLi or tBuLi, THF, at or below –90 °C), were employed for the stereospecific reagent-controlled homologation of boronic esters R0–Bpin (R0 = BnCH2, allyl, cHex, Ph). Addition of TBSOTf to the intermediate ate complexes gave β-silyloxyboronates that were converted to vicinal diol monosilyl ethers by oxidative work-up with aq. NaOOH. The 2°/2° (4–32 %, dr > 98:2), 2°/3° (21–66 %, dr ≥ 65:35), and 3°/3° (59–68 %, dr ≥ 95:5) contiguous stereodiad-containing compounds created in this manner were typically obtained in a highly stereocontrolled manner. In general, cis-sulfinyl epoxides afforded anti-like stereodiads, whereas trans-sulfinyl epoxides afforded syn-like stereodiads; however, as a result of its suspected configurational instability, LiCMe(O)CHPh gave anti-like 2°/3° motifs regardless of sulfinyl epoxide stereochemistry.
Infrared Spectra of the Novel Sn2H2 Species and the Reactive SnH1,2,3 and PbH1,2,3 Intermediates in Solid Neon, Deuterium, and Argon

Laser-ablated Sn atoms and H2 molecules in excess neon and argon react during condensation to produce SnH1,2,3,4 as identified from infrared spectra with D2 and HD substitution, and from agreement with frequencies calculated by density functional theory. The novel ditin species Sn2H2 is also formed in further reactions. The PbH1,2,3 intermediates are produced in analogous experiments. All four tin deuterides and the first three lead deuterides are observed in pure deuterium. Evidence is presented for the photosensitive MH3- and MH2- anions formed through electron capture processes.
A longitudinal test of impulsivity and depression pathways to early binge eating onset

Objective The very early engagement in bulimic behaviors, such as binge eating, may be influenced by factors that dispose individuals to impulsive action as well as by factors that dispose individuals to depressive symptomatology. Using a longitudinal design, we conducted the first test of the simultaneous operation of both risk factors as children transition from elementary to middle school. Method In a sample of 1,906 children, we assessed risk for impulsive action (negative urgency, which is the tendency to act rashly when distressed, and eating expectancies, which are learned anticipations that eating will alleviate negative mood) and risk for depression (negative affect and depressive symptomatology) and binge eating behavior at three time points using a longitudinal design: the end of fifth grade (last year of elementary school: T0), the beginning of sixth grade (first year of middle school: T1), and the end of sixth grade (T2). Results Both the impulsive action and depression pathways predicted very early engagement in binge eating: each accounted for variance beyond the other. Mediation tests found that T1 eating expectancies mediated the predictive influence of T0 negative urgency on T2 binge eating (z = 2.45, p < .01) and that T1 depressive symptoms mediated the influence of T0 negative affect on T2 binge eating (z = 2.04, p < .05). Discussion In children, elevated levels of both negative urgency and negative affect predict early binge eating. This finding has important clinical implications because there are different interventions for the two different risk processes. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:230–237)
Integration Strategies for Efficient Multizone Chemical Kinetics Models

Three integration strategies are developed and tested for the stiff, ordinary differential equation (ODE) integrators used to solve the fully coupled multizone chemical kinetics model. Two of the strategies tested are found to provide more than an order of magnitude of improvement over the original, basic level of usage for the stiff ODE solver. One of the faster strategies uses a decoupled, or segregated, multizone model to generate an approximate Jacobian. This approach yields a 35-fold reduction in the computational cost for a 20 zone model. Using the same approximate Jacobian as a preconditioner for an iterative Krylov-type linear system solver, the second improved strategy achieves a 75-fold reduction in the computational cost for a 20 zone model. The faster strategies achieve their cost savings with no significant loss of accuracy. The pressure, temperature and major species mass fractions agree with the solution from the original integration approach to within six significant digits; and the radical mass fractions agree with the original solution to within four significant digits. The faster strategies effectively change the cost scaling of the multizone model from cubic to quadratic, with respect to the number of zones. As a consequence of the improved scaling, the 40 zone model offers more than a 250-fold cost savings over the basic calculation.
Incompressible maps of surfaces and Dehn filling

Abstract We prove results showing that the existence of essential maps of surfaces in a manifold M obtained from a 3-manifold M by Dehn filling implies the existence of essential maps of surfaces in M.
Optimal consumption and portfolio policies when asset prices follow a diffusion process

Abstract We consider a consumption-portfolio problem in continuous time under uncertainty. A martingale technique is employed to characterize optimal consumption-portfolio policies when there exist nonnegativity constraints on consumption and on final wealth. We also provide a way to compute and verify optimal policies. Our verification theorem for optimal policies involves a linear partial differential equation, unlike the nonlinear partial differential equation of dynamic programming. The relationship between our approach and dynamic programming is discussed. We demonstrate our technique by explicitly computing optimal policies in a series of examples. In particular, we solve the optimal consumption-portfolio problem for hyperbolic absolute risk aversion utility functions when the asset prices follow a geometric Brownian motion. The optimal policies in this case are no longer linear when nonnegativity constraints on consumption and on final wealth are included. By these examples, one can see that our approach is much easier than the dynamic programming approach.
Modal Analysis of the Ice-Structure Interaction Problem

In this paper the authors build upon the single degree of freedom ice-structure interaction model initially proposed by Matlock, et al. (1969, 1971). The model created by Matlock, et al. (1969, 1971), assumed that the primary response of the structure would be in its fundamental mode of vibration. Modal analysis is used in this study, in which the response of each mode is superposed to find the complete modal response of the entire length of a pier subject to incremental ice loading. In Matlock, et al., the physical system is a bottom supported pier modeled as a cantilever beam. Realistic conditions such as ice accumulation on the pier modeled as a point mass and uncertainties in the ice characteristics are introduced in order to provide a stochastic response. The impact of number of modes in modeling is studied as well as dynamics due to fluctuations of ice impact height as a result of typical tidal fluctuations. A Poincare based analysis following on the research of Karr, et al. (1992) is employed to identify any periodic behavior of the system response. The intention of this work is to provide a foundation for future work coupling multiple piers and connecting structure for a comprehensive ice-wind-structural dynamics model.
Lattice path matroids: The excluded minors

A lattice path matroid is a transversal matroid for which some antichain of intervals in some linear order on the ground set is a presentation. We characterize the minor-closed class of lattice path matroids by its excluded minors.
A test of the chiral E8 current algebra on a 6D non-critical string

Abstract Compactifying the E 8 non-critical string in 6D down to 5D, the 6D strings give rise to particles and strings in 5D. Using the dual M-theory description compactified on an elliptically fibered Calabi-Yau we compare some of the 5D BPS states to what one expects from non-critical strings with an E 8 chiral current algebra. The E 8 multiplets of particle states comprise of 2-branes wrapping on irreducible curves together with bound states of several 2-branes.
The magnetic field of Mercury

The USA Mariner 10 spacecraft encountered Mercury three times in 1974–1975. The 1st and 3rd encounters provided detailed observations of a well developed, detached bow shock wave which results from the interaction of the solar wind. The planet possesses a global magnetic field, and modest magnetosphere, which deflects the solar wind. The field is approximately dipolar, with orientation in the same sense as Earth, tilted 12° from the rotation axis. The magnetic moment, 5×1022 Gauss−cm3, corresponds to an undistorted equatorial field intensity of 350γ, approximately 1% of Earth’s. The origin of the field, while unequivocally intrinsic to the planet, is uncertain.It may be due to remanent magnetization acquired from an extinct dynamo or a primordial magnetic field or due to a presently active dynamo. Among these possibilities, the latter appears more plausible at present. In any case, the existence of the magnetic field provides very strong evidence of a mature, differentiated planetary interior with a large core, Rc≈0.7RM, and a record of the history of planetary formation in the magnetization of the crustal rocks.
Prediction of Multilayer Printed Wiring Board Temperatures During Lamination

Measurements of temperature histories of epoxy/glass prepreg layers during multilayer printed wiring board lamination have been recently obtained. It is shown that the temperature histories may be predicted by an analysis of the transient heat flow process within the multilayer board (MLB). The analysis requires a knowledge of the press platen temperature history during laminations and the thermal resistance of the padding material. Theoretically predicted results show close agreement with the experimental data for both 5-layer and 15-layer MLB's using the "hot press" as well as the "cold press" cycles. The present method may be used in the design of MLB lay-ups, in particular the determination of the necessary padding thickness to achieve heating rates which give adequate timing "windows" for cure pressure applications. The present theory has been applied to study the effect of kraft paper padding on the prepreg temperatures. Results are shown for both 15-and 5-layer laminations employing the hot press as well as cold press cycles. The number of kraft paper sheets used is shown to have a significant bearing on the temperatures.
Molecular detection and characterisation of circulating tumour cells and micrometastases in solid tumours.

The detection and molecular characterisation of circulating tumour cells (CTC) and micrometastases may have important prognostic and therapeutic implications. Because their numbers are very small, these tumour cells are not easily detected using conventional methods. In the last decade, numerous groups have attempted to detect occult tumour cells in solid malignancies using the highly sensitive reverse transcriptase polymerase chain reaction (RT-PCR). These assays were in the vast majority directed against tissue-specific markers. PCR was shown to be superior to conventional techniques in detecting occult tumour cells allowing the identification of one malignant cell mixed with 1-10 million normal cells. In some tumours like melanoma and prostatic carcinoma, tissue-specific transcripts were detected with high specificity in the blood of patients with localised and advanced disease. In some reports, PCR was shown to be a strong predictor of poorer outcome. However, due to the many limitations of PCR (e.g false-positives), many groups are developing new approaches for the detection of occult tumour cells. The most attractive technique involves immunomagnetic isolation of CTC and micrometastases prior to downstream analysis. The tumour-rich magnetic fraction can be subjected to RT-PCR, immunocytochemistry and in situ hybridisation. This will lead to better quantification and molecular characterisation of these tumour cells. In conclusion, the molecular detection and characterisation of occult tumour cells offer a great opportunity for better stratifying patients with solid tumours and for developing new prognostic markers and targeted therapies.
A Multi-Dimensional Lieb-Schultz-Mattis Theorem

For a large class of finite-range quantum spin models with half-integer spins, we prove that uniqueness of the ground state implies the existence of a low-lying excited state. For systems of linear size L, with arbitrary finite dimension, we obtain an upper bound on the excitation energy (i.e., the gap above the ground state) of the form (C log L)/L. This result can be regarded as a multi-dimensional Lieb-Schultz-Mattis theorem [14] and provides a rigorous proof of the main result in [8].
The Transiting Exoplanet Host Star GJ 436: A Test of Stellar Evolution Models in the Lower Main Sequence, and Revised Planetary Parameters

Knowledge of the stellar parameters for the parent stars of transiting exoplanets is a prerequisite for establishing the planet properties themselves, and often relies on stellar evolution models. GJ 436, which is orbited by a transiting Neptune-mass object, presents a difficult case because it is an M dwarf. Stellar models in this mass regime are not as reliable as for higher mass stars, and tend to underestimate the radius. Here we use constraints from published transit light curve solutions for GJ 436 along with other spectroscopic quantities to show how the models can still be used to infer the mass and radius accurately, and at the same time allow the radius discrepancy to be estimated. Similar systems should be found during the upcoming Kepler mission, and could provide in this way valuable constraints to stellar evolution models in the lower main sequence. The stellar mass and radius of GJ 436 are M = 0.452 M☉ and R = 0.464 R☉, and the radius is 10% larger than predicted by the standard models, in agreement with previous results from well-studied double-lined eclipsing binaries. We obtain an improved planet mass and radius of Mp = 23.17 ± 0.79 M⊕ and Rp = 4.22 R⊕, a density of ρp = 1.69 g cm-3, and an orbital semimajor axis of a = 0.02872 ± 0.00027 AU.
On time-space classes and their relation to the theory of real addition

A new lower bound on the computational complexity of the theory of real addition and several related theories is established: any decision procedure for these theories requires either space 2?n or nondeterministic time 2?n2 for some constant ?0 and infinitely many n.The proof is based on the families of languages TISP(T(n), S(n)) which can be recognized simultaneously in time T(n) and S(n) and the conditions under which they form a hierarchy.
Nuclear magnetic resonance and magnetization studies of the ferromagnetic ordering temperature suppression in Ru deficient SrRuO3

Abstract The synthesis of SrRuO 3 under high-pressure oxygen produces a nonstoichiometric form with randomly distributed vacancies on the Ru sites, along with a significantly reduced ferromagnetic ordering temperature. In order to gain additional insight into the suppression of the ferromagnetism, local studies utilizing 99,101 Ru zero-field spin-echo NMR, Ru K-edge XAFS and XANES, along with complimentary magnetization and X-ray diffraction measurements, have been carried out on samples of SrRuO 3 annealed at both (ambient) atmospheric pressure and ‘high-pressure’ oxygen (600 atm). Consistent with previous work, the NMR spectrum for ambient SrRuO 3 consists of two well-defined peaks at 64.4 and 72.2 MHz corresponding to the 99 Ru and 101 Ru isotopes, respectively, and a hyperfine field of 329 kG. Although the magnetization measurements show a lower ferromagnetic ordering temperature for the high-pressure oxygen sample (90 K compared to 160 K for the ambient sample), the NMR spectrum shows no significant shift in the two peak frequencies. However, the two peaks exhibit considerable broadening, along with structure on both the low and high frequency sides which is believed to be quadrupolar in origin. Analysis of the Ru K-edge XAFS reveals more disorder in the Ru–O bond for the high-pressure oxygen sample compared to the ambient sample. Furthermore, XANES of Ru K-edge analysis indicates no difference in the valence of Ru between the two samples. The magnetic behavior indicates the existence of some vacancies on the Ru sites for the high-pressure oxygen sample.
Microcredit and the Poorest of the Poor: Theory and Evidence from Bolivia

Abstract We construct a theoretical framework that describes the social worth of a microfinance organization in terms of the depth, worth to users, cost to users, breadth, length, and scope of its output. We then analyze evidence of depth of outreach for five microfinance organizations in Bolivia. Most of the poor households reached by the microfinance organizations were near the poverty line—they were the richest of the poor. Group lenders had more depth of outreach than individual lenders. The urban poorest were more likely to be borrowers, but rural borrowers were more likely to be among the poorest.
Stereochemical aspects of cytosolic epoxide hydrolase hydration of methyl diepoxystearates

Abstract Hydration of methyl diepoxystearate ( 2 ) at high cytosolic epoxide hydrolase (CEH) concentration produces the corresponding tetraol, while at physiological CEH concentration four tetrahydrofuran diol products ( 3–6 ) are produced. These same four products are obtained in the acid-catalyzed hydration of 2 . Spectroscopic studies, primarily EI mass spectrometry and difference spectrum NOE, are reported which establish the regio- and stereoselectivity of 2 → 3–6 (MS differentiating 3 4 from 5 6 and NOE differentiating 3 5 from 4 6 ). The observed syn arrangement of the two adjacent groups (i.e., substituents at C 2 and C 3 ) in the four THF-diols can only arise from an A 2 type opening of the first epoxide. The resulting epoxydiol intermediate then cyclizes by A 2 opening of the second cis -epoxide as established by synthesis of these hypothetical epoxydiol intermediates and their subsequent conversion to THF-diols 3–6 .
An ab initio study of the geometry and energy of the four planar conformers of glyoxylic acid and the glyoxylate ion

Abstract The structures and energies of the four planar conformers of glyoxylic acid and the glyoxylate ion have been studied ab initio using the unscaled 4—31G basis set with full geometry optimization. Changes in the CO, OH and CO bond lengths in the conversion of the cc conformer into the ct and tt conformers, and into the tc conformer, are consistent with the formation of four-membered and five-membered hydrogen-bonded ring structures, respectively. Changes in the distances between the nearest non-bonded atoms around each C atom reveal that the internal geometry of the CHO and COOH groups is significantly affected by cis—trans isomerization with respect to the OCCO backbone, and that the geometry of the CHO group is affected by proton dissociation from the COOH group. Furthermore, the movement of the component atoms in each functional group, characterized as clockwise or anticlockwise about the C atom, results in some cases in a rotation of the functional group as a whole. Whereas experiment shows the tc conformer to be more stable than the tt by 1.2 ± 0.5 kcal mol −1 , the calculations find the tt conformer to be the most stable, separated in energy from the ct, tc and cc conformers by 0.4, 1.4 and 10.7 kcal mol −1 , respectively. Augmentation of the 4—31G basis set in several forms, and use of (9,5/4) and (9,5/4,1) basis sets, only served to decrease slightly the tt/tc energy difference, not change the sign. The calculated proton affinity of the glyoxylate ion with respect to the tt conformer is 342.7 kcal mol −1 , compared to 357.7 kcal mol −1 for the formate ion. The expectation energy differences Δ V nn , Δ V ee and Δ V en for the cis—trans isomerization of the ct and cc conformers are opposite in sign to those for the glyoxal reaction, and in magnitude they all far exceed the Δ E T values, which shows that hydroxyl group substitution has a much greater influence than a comparison of only the Δ E T values would suggest.
Effect of Wettability Alteration on Water/Oil Relative Permeability, Dispersion, and Flowable Saturation in Porous Media

Wettability alteration was shown to affect strongly water/oil two-phase flow behavior in Berea and Loudon reservoir cores. Two examples of wettability alteration were realized by core aging and core extraction. With a steady-state method coupled with tracer analyses, these changes in wettability were shown to affect relative permeabilities, tivedispersivities, and flowable saturations in the cores. The changes in wettability were also confirmed by waterflood and spontaneous-imbibition tests. Dispersion in steady-state two-phase flow was found to be a strong function of saturation and wettability. Dispersivity of each phase increases with decreasing phase saturation. Flow of the nonwetting phase was dispersed much more than that of the wetting phase. A large fraction of the nonwetting-phase saturation was found to be bypasses or nonflowable, while the wetting phase was completely flowable. The correlation between the flowable phase saturation and in-situ saturation was strongly affected by wettability alteration.
Direct amination of homoenolates catalyzed by N-heterocyclic carbenes.

N-Heterocyclic carbenes derived from N-mesityl-N-methyltriazolium salts are effective catalysts for generating homoenolate species from α,β-unsaturated aldehydes. The unique intermediate adds to the electrophilic nitrogen of 1-acyl-2-aryldiazenes, and the resulting activated carbonyl unit undergoes an intramolecular acylation event. This formal [3+2] cycloaddition between α,β-unsaturated aldehydes and acylaryldiazenes, catalyzed by an N-heterocyclic carbene, produces substituted pyrazolidinones in good yields. This new NHC-catalyzed reaction accommodates aromatic and alkyl α,β-unsaturated aldehydes and various aromatic diazenes. A chiral triazolium salt catalyzes the formation of the pyrazolidinone product in moderate yield and good enantioselectivity. The pyrazolidinones can undergo reductive N−N bond cleavage to give β-amino acid derivatives.
Stochastic modeling and optimization of phage display.

Phage display, SELEX and other methods of combinatorial chemistry have become very popular means of finding ligands with high affinities to given targets. Despite their success, they suffer from numerous sources of error and bias, such as very low initial concentrations of species, non-specific binding, and the sampling of only a tiny fraction of the library at the end of an experiment. To understand the interaction of these errors and to better devise molecular search strategies that take the errors into account, I devise and analyze a highly detailed model of phage display. The model is specifically designed to study the influence of the stochastic nature of each laboratory step. The model includes phage multivalency, multiple classes of targets, and solid-phase equilibrium and washing, yet it is amenable to analytic results and rapid computer simulation. With both analytic and simulation approaches, I: (1) describe the effects of target concentration, phage valency, degree of background binding and other laboratory parameters on the probabilities of phage binding and of being selected; (2) show the effects of an increasing selection stringency strategy and how it results in a tradeoff between rapid library enrichment and high probability of sampling the best ligands; and (3) show how the number of phage sampled for detailed study at the end of a search alters search success. The work concludes with several practical suggestions for the control of selection stringency.
Catalytic Aminohalogenation of Alkenes and Alkynes.

Transition metal carbides (TMCs) have attracted a significant amount of attention over the past few years as electrocatalyst support materials. TMCs are interesting because of their similar electronic structures to noble metals near the Fermi level (i.e., WC and Pt), which can promote electron transfer between the catalyst and its support—to enhance the stability of supported Pt nanoparticles as well as enhance its intrinsic activity for select reactions. This perspective article summarizes both theoretical and experimental results for Pt catalysts supported by TMCs for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) to explore the interaction mechanism of the catalysts and the carbide supports. The strategies to improve the present carbide supports for HER and ORR are also discussed, which is expected to shed light on future development of TMC electrocatalyst supports.
THE CULTURAL CONTEXT OF CONSTRUCT VALIDITY AND THE ETHICS OF GENERALIZABILITY

This article considers the mutual relevance of four themes: cultural diversity, construct validity, population generalizability, and professional ethics. Questions regarding construct validity are considered in the context of both measurement and intervention. The implications of the existence and the absence of empirical evidence on which to base validity generalizations are considered in reference to decision making in the provision of services. Ethical dilemmas that arise from these considerations, which face the applied professional in a culturally diverse society, are discussed within an emerging framework for resolving them. Previous research is reviewed to illustrate validity generalization limits. Also included are an assessment of research needs and a discussion of future directions for research and evaluation.
A Perfect Price Discrimination Market Model with Production, and a Rational Convex Program for It

Recent results showing PPAD-completeness of the problem of computing an equilibrium for Fisher's market model under additively separable, piecewise-linear, concave (PLC) utilities have dealt a serious blow to the program of obtaining efficient algorithms for computing equilibria in “traditional” market models, and has prompted a search for alternative models that are realistic as well as amenable to efficient computation. In this paper, we show that introducing perfect price discrimination into the Fisher model with PLC utilities renders its equilibrium polynomial time computable. Moreover, its set of equilibria are captured by a convex program that generalizes the classical Eisenberg-Gale program, and always admits a rational solution. We also give a combinatorial, polynomial time algorithm for computing an equilibrium. Next, we introduce production into our model, and again give a rational convex program that captures its equilibria. We use this program to obtain surprisingly simple proofs of both welfare theorems for this model. Finally, we also give an application of our price discrimination market model to online display advertising marketplaces.
Distorted Metrics on Trees and Phylogenetic Forests

We study distorted metrics on binary trees in the context of phylogenetic reconstruction. Given a binary tree T on n leaves with a path metric d, consider the pairwise distances {d(u,v)} between leaves. It is well known that these determine the tree and the d length of all edges. Here, we consider distortions d of d such that, for all leaves u and v, it holds that |d(u,v)-dmacr(u,v)|<f/2 if either d(u,v)<M+f/2 or d(u,v)<M+f/2, where d satisfies flesd(e)lesg for all edges e. Given such distortions, we show how to reconstruct in polynomial time a forest T1.....T0 such that the true tree T may be obtained from that forest by adding alpha-1 edges and alpha-1les2-Omega(M/g)n. Our distorted metric result implies a reconstruction algorithm of phylogenetic forests with a small number of trees from sequences of length logarithmic in the number of species. The reconstruction algorithm is applicable for the general Markov model. Both the distorted metric result and its applications to phylogeny are almost tight