cssi/SciSciGPT-SciSciNet huggingface dataset:
Portugal in space

Abstract In the 14th and 15th centuries, Portugal went discovering and conquering sea and land all over the world. History was forever changed by the courage and bravery of one people. The Portuguese navy introduced new techniques of navigation, using astronomical instruments like the astrolabe. In this paper, some episodes of the Portuguese relation with astronomy and space will be highlighted. These refer not only to governmental measures and decisions, but also to initiatives of the society at large, telling of the important role that this subject has played in the Portuguese society throughout the years.
Combining genetic algorithms and neural networks to build a signal pattern classifier

In this paper we show how genetic algorithms and neural networks are combined to build a high-performance signal pattern classifier (GNSPC). Signal patterns are intrinsic to many sensor-based systems. The goal of GNSPC is to differentiate among large numbers of signal pattern classes with low classification cost and high classification performance. Classification performance is measured by the correct classification of noisy signal patterns despite using pure signal patterns for building the classifier. GNSPC is basically a decision tree classifier with similarity classification rules. The rules are used to test the similarity of signal patterns. A combination of a genetic algorithm and a neural network is used to find the best rules for the decision tree. This combination provides powerful classification capabilities with great tuning flexibility for either performance or cost-efficiency. Learning techniques are employed to set the genetic algorithm global parameters and to obtain training data for the neural network.
Young adult mortality following severe physiological stress in childhood: Skeletal evidence

Numerous studies report that early childhood biological stress impairs health in later adulthood. Overwhelmingly these studies are based on modern data, when health conditions are quite good by historical standards. Potentially much can be learned by examining the relationship within populations that lived under enormous pressure, enduring life expectancies less than one-half of those found in industrial countries of the late twentieth century. This paper uses the skeletal remains of over 3000 individuals who lived in the Western Hemisphere as long as 6000 years ago to probe the connection between several markers of early childhood stress and survival from approximately age 15 to 30. In a logit model with explanatory variables that control for sex and ethnicity, the probability of survival was systematically 7.6 percentage points less among individuals with two or more hypoplasias, 3.9 percentage points less for those with cribra orbitalia or porotic hyperostosis, and 4.6 percentage points less for individuals stunted by 20 cm in height. The paper compares these findings with those from studies on modern data and concludes with suggestions for research.
Competing structural instabilities in cubic perovskites.

We study the antiferrodistortive instability and its interaction with ferroelectricity in cubic perovskite compounds. Our first-principles calculations show that coexistence of both instabilities is very common. We develop a first-principles scheme to study the thermodynamics of these compounds when both instabilities are present, and apply it to SrTi${\mathrm{O}}_{3}$. We find that increased pressure enhances the antiferrodistortive instability while suppressing the ferroelectric one. Moreover, the presence of one instability tends to suppress the other. A very rich $P$- $T$ phase diagram results.
Synthesis of allylic and homoallylic alcohols from unsaturated cyclic ethers using a mild and selective C–O reduction approach

Unsaturated cyclic ethers can be mildly and selectively reduced with catalytic amounts of B(C6F5)3 in the presence of an alkylsilane. The allylic position is preferentially reduced with minimal or no scrambling of olefin geometry. For electronically equivalent substrates, steric factors guide the reducing agent to the least substituted site.
Single magnetic molecule between conducting leads: Effect of mechanical rotations

We study spin-rotation effects in a magnetic molecule bridged between two conducting leads. The dynamics of the total angular momentum couples spin tunneling to the mechanical rotations. The Landau-Zener spin transition produced by the time-dependent magnetic field generates a unique pattern of mechanical oscillations that can be detected by measuring the electronic tunneling current through the molecule.
A Facility to Produce Uniform Space Charge for Evaluating ION Measuring Instruments

A low-speed wind tunnel containing space charge has been constructed and evaluated. The facility is used for testing the performance of ion counters and net space charge measuring devices. For different operating conditions, space charge densities in the test volume range from 2.5-5.7 x 10 -8 C/m 3 . The space charge density is spatially uniform within 5% over more than than 900) of the cross sectional area of the test volume, but decreases by approximately 20% between two positions separated by 1 m. Ion densities achieved in this system are comparable to those found near high-voltage dc transmission lines but are free from the accompanying large electric fields.
Magnetic levitation-based Martian and Lunar gravity simulator

Missions to Mars will subject living specimens to a range of low gravity environments. Deleterious biological effects of prolonged exposure to Martian gravity (0.38 g), Lunar gravity (0.17 g), and microgravity are expected, but the mechanisms involved and potential for remedies are unknown. We are proposing the development of a facility that provides a simulated Martian and Lunar gravity environment for experiments on biological systems in a well controlled laboratory setting. The magnetic adjustable gravity simulator will employ intense, inhomogeneous magnetic fields to exert magnetic body forces on a specimen that oppose the body force of gravity. By adjusting the magnetic field, it is possible to continuously adjust the total body force acting on a specimen. The simulator system considered consists of a superconducting solenoid with a room temperature bore sufficiently large to accommodate small whole organisms, cell cultures, and gravity sensitive bio-molecular solutions. It will have good optical access so that the organisms can be viewed in situ. This facility will be valuable for experimental observations and public demonstrations of systems in simulated reduced gravity. c2005 Published by Elsevier Ltd on behalf of COSPAR.
The Effect of the Private Securities Litigation Reform Act of 1995 on Accounting Discretion of Client Managers of Big 6 and Non‐Big 6 Auditors

This study examines how the Private Securities Litigation Reform Act of 1995 (PSLRA) affects auditors' incentives to curtail earnings management by client managers. The most significant reform of PSLRA was the elimination of joint and several liability under which auditors and other parties could be named to lawsuits because of ‘deep pockets’ rather than culpability. While the elimination of joint and several liability provides significant relief to auditors from litigation, opponents of PSLRA argue that it discourages meritorious lawsuits and lowers audit quality, reducing investor confidence in markets. The potential benefit would be greatest for Big 6 firms, who have the highest exposure (largest clients) and significant resources to pay damages. In this paper we argue that if PSLRA induces decreases in audit quality, then we should expect increases in the prevalence of accruals after this Act. To investigate this issue we examine the discretionary accruals of a sample of 2,600 companies three years be...
Troponin Regulatory Function and Dynamics Revealed by H/D Exchange-Mass Spectrometry

Muscle contraction is tightly regulated by Ca2+ binding to the thin filament protein troponin. The mechanism of this regulation was investigated by detailed mapping of the dynamic properties of cardiac troponin using amide hydrogen exchange-mass spectrometry. Results were obtained in the presence of either saturation or non-saturation of the regulatory Ca2+ binding site in the NH2 domain of subunit TnC. Troponin was found to be highly dynamic, with 60% of amides exchanging H for D within seconds of exposure to D2O. In contrast, portions of the TnT-TnI coiled-coil exhibited high protection from exchange, despite 6 h in D2O. The data indicate that the most stable portion of the trimeric troponin complex is the coiled-coil. Regulatory site Ca2+ binding altered dynamic properties (i.e. H/D exchange protection) locally, near the binding site and in the TnI switch helix that attaches to the Ca2+-saturated TnC NH2 domain. More notably, Ca2+ also altered the dynamic properties of other parts of troponin: the TnI inhibitory peptide region that binds to actin, the TnT-TnI coiled-coil, and the TnC COOH domain that contains the regulatory Ca2+ sites in many invertebrate as opposed to vertebrate troponins. Mapping of these affected regions onto the troponin highly extended structure suggests that cardiac troponin switches between alternative sets of intramolecular interactions, similar to previous intermediate resolution x-ray data of skeletal muscle troponin.
WHAT DRIVES TIME VARIATION IN EMERGING MARKET SEGMENTATION

I use American Depositary Receipts and underlying stocks to test the level of integration of the stock markets of Argentina, Chile, and Mexico into the world capital market in the post-liberalization period. I find that these markets experience time-varying integration and are, on average, still not highly internationally integrated. Furthermore, there is no distinct trend toward higher levels of integration. In fact, the markets of Argentina and Mexico have become increasingly segmented over the post-liberalization period. I find that financial and economic openness, stock market liquidity and volatility, and the state of the currency market significantly affect the level of segmentation.
The analysis of simulation experiments

Abstract Simulation experiments are experiments performed with a mathematical model over time. The steps to be followed in a simulation study include problem formulation, setting objectives, model building, data collection, coding, verification, validation, experimental design, production runs and analysis, and simulation report. Simulation experiments permit: (a) evaluation of estimates of one or more of the performance measures of the system under study, (b) evaluation of operating performance of a system prior to its implementation, (c) comparison of various operational alternatives of a real system without perturbing the system, (d) comparison of alternative system designs on the basis of some performance measures, and (e) time compression or expansion so that timely policy decisions and/or detailed system evolution can be made without ambiguity. This paper focuses on various aspects that improve the analysis of simulation experiments.
Statistical Constraints on State Preparation for a Quantum Computer

Quantum computing algorithms require that the quantum register be initially present in a superposition state. To achieve this, we consider the practical problem of creating a coherent superposition state of several qubits. We show that the constraints of quantum statistics require that the entropy of the system be brought down when several independent qubits are assembled together. In particular, we have: (i) not all initial states are realizable as pure states; (ii) the temperature of the system must be reduced. These factors, in addition to decoherence and sensitivity to errors, must be considered in the implementation of quantum computers.
Regulation of mast cell histamine release by neurotensin

Neurotensin (NT), a neuropeptide found both centrally and peripherally, stimulated release of histamine from rat peritoneal mast cells in a dose-dependent manner. Release was evident by 10 nM and reached a plateau of 15–20% total cellular histamine by 10−7–10−6 M NT. Optimal conditions for stimulation occurred at pH 6.5–7.5, 37°C and at calcium concentrations of ≤1 mM. Release was complete within 2 minutes of peptide addition. Studies of histamine release by NT analogues indicated that the C-terminus is the biologically active portion of the molecule in this system, as is true of all other systems responsive to NT (1). D-Trp11-NT, which acts as a NT antagonist in several peripheral NT-sensitive tissues (2,3), also inhibited NT action on mast cells. Manipulations involving Ca2+ availability suggest that the mechanism of NT stimulation may involve use of intracellular Ca2+ to a greater extent than extracellular Ca2+. Lowering the extracellular Ca2+ concentration or blocking influx of extracellular Ca2+ with lanthanum (La3+), had little effect on NT-induced release, whereas Ca2+ depletion by treatment with ethylenediaminetetracetic acid (EDTA) or blockade of intracellular Ca2+ mobilization by N,N-(diethylamino)octyl 3,4,5-trimethoxybenzoate (TMB-8), inhibited the response to NT. Increasing cellular levels of adenosine 3′, 5′-cyclic monophosphate (cAMP), by treatment with 8-bromo-cAMP or stimulation with prostaglandin E2 (PGE2) in the presence of isobutylmethylxanthine (IBMX), served to reduce histamine release by NT, indicating that cAMP may play a role in NT stimulation.
The Eisenbud-Koh-Stillman conjecture on linear syzygies

De®nition 0.1. A variety X and line bundle L has property Np for p 0 an integer if: (1) p  0 It is normally generated, i.e. SkH0 X ;L ! H0 X ; L k is surjective for all k 0; (2) p  1 It is normally generated and the kernel of k 0SH X ; L ! k 0H X ; L k is generated by quadrics; (3) p 2 It has properties N0 and N1 and the k'th syzygies among the quadrics are generated by linear syzygies for all 1 k p y 1.
Variables influencing expatriate learning and organizational learning

Purpose – The purpose of this paper is to identify the variables that influence the international assignment – expatriate learning relationship and the expatriate learning – organizational learning relationship. Design/methodology/approach – The paper contains a literature review of the research on expatriates' learning and organizational learning Findings – The paper provides an integrative framework that identifies the moderating variables that influence both the relationship between the expatriate international assignment and expatriate learning as well as the relationship between expatriate learning and organizational learning. In addition, this framework specifies the process by which the international assignment influences organizational learning and shows that expatriate learning mediates this relationship. Several hypotheses were generated to provide avenues for future investigation. Research limitations/implications – The paper does not provide an exhaustive set of the moderating variables and do...
Radioactive Ni* tracer study of the nickel silicide growth mechanism

Abstract A tracer technique using radioactive 56 Ni ∗ was applied to investigate the growth mechanisms of Ni 2 Si, NiSi and NiSi 2 on Si〈100〉 and Si〈111〉 wafers. A thin Ni ∗ tracer layer initially at the Ni-Si interface was observed to migrate and spread during the growth of nickel silicides at 350, 450 and 800 °C. These data are discussed, together with other results from 31 Si ∗ tracer work and xenon marker experiments. Ni appears to be the dominant moving species in all cases, diffusing both substitutionally and by grain boundary paths (in comparable amounts) for Ni 2 Si and substitutionally for NiSi and NiSi 2 .
Cognitive-behavioral therapy for obsessive-compulsive disorder: a meta-analysis of treatment outcome and moderators

The present investigation employed meta-analysis to examine the efficacy of cognitive-behavioral therapy (CBT) for obsessive-compulsive disorder (OCD) as well as potential moderators that may be associated with outcome. A literature search revealed sixteen randomized-controlled trials (RCTs) with a total sample size of 756 participants that met inclusion criteria. Results indicated that CBT outperformed control conditions on primary outcome measures at post-treatment (Hedges's g = 1.39) and at follow-up (Hedges's g = 0.43). Subsequent analyses revealed few moderators of CBT efficacy. Neither higher pre-treatment OCD (p = 0.46) or depression symptom severity (p = 0.68) was significantly associated with a decrease in CBT effect size. Similarly, effect size did not vary as a function of 'type' of CBT, treatment format, treatment integrity assessment, blind assessment, age of onset, duration of symptoms, percentage of females, number of sessions, or percent comorbidity. However, active treatments showed smaller effect sizes when compared to placebo controls than when compared to waitlist controls. Effect sizes were also smaller for adult RCTs than child RCTs. Likewise, older age was associated with smaller effect sizes. However, an association between age and effect size was not observed when examining child and adult samples separately. This review indicates that while CBT is efficacious in the treatment of OCD, more research is needed to identify processes that may predict more favorable treatment responses.
A stable classification of Lefschetz fibrations

We study the classification of Lefschetz fibrations up to stabilization by fiber sum operations. We show that for each genus there is a "universal" fibration f 0 g with the property that, if two Lefschetz fibrations over S 2 have the same Euler-Poincare characteristic and signature, the same numbers of reducible singular fibers of each type, and admit sections with the same self-intersection, then after repeatedly fiber summing with f 0 g they become isomorphic. As a consequence, any two compact integral symplectic 4-manifolds with the same values of (c 2 1 , c 2 , c 1 ·[ω], [ω] 2 ) become symplectomorphic after blowups and symplectic sums with f 0 g .
Human ovarian 17-ketosteroid oxidoreductase: unique characteristics of the granulosa-luteal cell and stromal enzyme.

Objective: We attempted to test the hypothesis that distinct forms of the 17-ketosteroid oxidoreductase exist in the human ovary and to compare its activity in stroma obtained from normally cycling women and from hyperandrogenic women. Study Design: Human ovarian granulosa-luteal cell and stromal 17-ketosteroid oxidoreductase were examined in cell incubations and subcellular homogenates. Results: In subcellular homogenates of granulosa-luteal cells 17-ketosteroid oxidoreductase activity was greater in the cytosol fraction than in the membrane fraction. In contrast, in homogenates of both ovarian stroma and Leydig cells its activity was greater in the membrane fraction than in the cytosol fraction. At the substrate concentrations used estrone was a better substrate than androstenedione for the granulosa-luteal cell 17-ketosteroid oxidoreductase. In contrast, androstenedione was a better substrate than estrone for that in ovarian stromal and Leydig cell membranes. In incubations of ovarian stroma from hyperandrogenic women, significantly more testosterone accumulated in the medium per milligram of tissue than in the medium of incubations of ovarian stroma from normally cycling women (142 ± 48 vs 7.9 ± 7.5 pg testosterone per milligram of tissue per 48 hours, mean ± SD, p p p Conclusion: The localization (cytosol fraction) and substrate specificity (estrone) of the granulosa-luteal cell 17-ketosteroid oxidoreductase enzyme resembles that seen in human placenta. The localization (membrane fraction) and substrate specificity (androstenedione) of the ovarian stromal 17-ketosteroid oxidoreductase enzyme resembles that seen in Leydig cells. It may be one enzyme that exists in multiple forms or it may be two (or more) enzymes. In some hyperandrogenic women the ovarian stromal 17-ketosteroid oxidoreductase may be more active than in normally cycling women, contributing to an abnormally increased testosterone production rate.
Catalytic Asymmetric Silane Alcoholysis: Practical Access to Chiral Silanes

A new asymmetric synthesis of chiral silanes has been developed. Chiral phosphine-modified copper complexes catalyze the alcoholysis of prochiral dihydrosilanes with good to excellent stereoselectivity at silicon. The application of this methodology to the tandem silylformylation-allylsilylation of alkynes has been demonstrated.
Automated pancreatic cyst screening using natural language processing: A new tool in the early detection of pancreatic cancer

Abstract Introduction As many as 3% of computed tomography (CT) scans detect pancreatic cysts. Because pancreatic cysts are incidental, ubiquitous and poorly understood, followup is often not performed. Pancreatic cysts may have a significant malignant potential and their identification represents a ‘window of opportunity’ for the early detection of pancreatic cancer. The purpose of this study was to implement an automated Natural Language Processing (NLP)based pancreatic cyst identification system. Method A multidisciplinary team was assembled. NLPbased identification algorithms were developed based on key words commonly used by physicians to describe pancreatic cysts and programmed for automated search of electronic medical records. A pilot study was conducted prospectively in a single institution. Results From March to September 2013, 566 233 reports belonging to 50 669 patients were analysed. The mean number of patients reported with a pancreatic cyst was 88/month (range 78–98). The mean sensitivity and specificity were 99.9% and 98.8%, respectively. Conclusion NLP is an effective tool to automatically identify patients with pancreatic cysts based on electronic medical records (EMR). This highly accurate system can help capture patients ‘atrisk’ of pancreatic cancer in a registry.
Structural comparisons between GABA, bicuculline and semi-rigid GABA analogues

Abstract Variable-temperature NMR results, including counterion effects on chemical shifts, establish that in solution the N -methyl and protanated salts (Cl or I) of the GABA antagonist bicuculline (BIC) are in just one conformation (θ ≅ 270°). Superposition of the N + and COO − charge centres of the GABA molecule with the corresponding charge centres in the BIC salts reveals an approximately linear arrangement of charge centres. The same arrangement is also found in the weak GABA A antagonists iso-THIP and iso-THAZ. A similar comparison of GABA with potent semi-rigid GABA A agonists yields a Y-shaped arrangement of charge centres. This clear difference may offer a structural basis for the distinction between GABA A agonist and antagonist action.
On an extension of Galligo's theorem concerning the Borel-fixed points on the Hilbert scheme

Abstract Given an ideal I and a weight vector w which partially orders monomials we can consider the initial ideal in w ( I ) which has the same Hilbert function. A well known construction carries this out via a one-parameter subgroup of a GL n + 1 which can then be viewed as a curve on the corresponding Hilbert scheme. Galligo [A. Galligo, Theoreme de division et stabilite en geometrie analytique locale, Ann. Inst. Fourier (Grenoble) 29 (2) (1979) 107–184, vii] proved that if I is in generic coordinates, and if w induces a monomial order up to a large enough degree, then in w ( I ) is fixed by the action of the Borel subgroup of upper-triangular matrices. We prove that the direction the path approaches this Borel-fixed point on the Hilbert scheme is also Borel-fixed.
New Compounds: Fatty Acid and Long Chain Hydrocarbon Derivatives Containing a Strong Chelating Agent

Fatty acid and long chain hydrocarbon analogs that contain a strong chelating group were synthesized as part of an effort to determine if the biological function of the fatty acid can be used to transport metallic isotopes to the myocardium.
The complex hyperbolic geometry of the moduli space of cubic surfaces

Recall that the moduli space of smooth (that is, stable) cubic curves is isomorphic to the quotient of the upper half plane by the group of fractional linear transformations with integer coefficients. We establish a similar result for stable cubic surfaces: the moduli space is biholomorphic to a quotient of the compex 4-ball by an explict arithmetic group generated by complex reflections. This identification gives interesting structural information on the moduli space and allows one to locate the points in complex hyperbolic 4-space corresponding to cubic surfaces with symmetry, e.g., the Fermat cubic surface. Related results, not quite as extensive, were announced in alg-geom/9709016.
Human capital resources and requirements across the metropolitan hierarchy of the USA

This article is devoted to an investigation of the forms of human capital that characterize cities at different levels of the US urban hierarchy. Basic data on human capital are drawn from the O*Net information system. A first analytical exercise shows that for the USA as a whole, occupations marked by broadly cognitive human capital assets gained in employment over the period from 2000 to 2006, whereas employment in occupations marked by broadly physical human capital assets declined. These same types of assets bear a distinctive relationship to the urban hierarchy, with the former being concentrated in large metropolitan areas, and the latter in small. Changes in these assets over the 2000-2006 period are then examined. Surprisingly, cognitive assets increased most strongly in small metropolitan areas and physical assets increased most strongly in large. Further analysis of these findings suggests that they are quite consistent with a wider view of the contemporary urban economy. In particular, in large metropolitan areas, expanding human capital assets focused on the physical abilities of workers has nothing to do with the ‘old’ economy as such, but represents a major—and hitherto much overlooked—segment of the labor force whose functions revolve around the maintenance of the material and social fabric of life in those areas.
Quality assurance requirements for a large Li/SOCl2 battery for spacecraft applications

A large lithium thionyl chloride (Li/SOCl2) spacecraft battery is currently being fabricated. When flown, this battery will consist of as many as 1080 "F"-size cells with an ultimate capacity of more than 2000 A-h. This work presents the acceptance and qualification test flows used for evaluating and screening the cells that compose the modules and battery assemblies. We also present data and analyses on the acceptance and qualification testing of the Li/SOCl2 cells. On the average, these F cells have a mean capacity of 18 A-h; select lots meet our goal of having less than a 5% coefficient of variation for the cell capacity.
The Impact of the 2008 Financial Crisis on Withdrawals of Retirement Wealth

During the financial crisis of 2007–2009, the market value of retirement assets held in stock fell by 32%. The objective of this study is to show how a severe financial crisis affects the withdrawal patterns of retirees. Specifically, the authors examine how withdrawal patterns change when an unexpected major investment shock at various years into retirement is induced artificially. The results show that equally weighted portfolio of stocks and bonds performs better than a portfolio of 100% stock, or a portfolio of 100% bonds by providing a more stable withdrawal pattern.
Cyclodextrins: a versatile tool in separation science

Cyclodextrins have been used extensively in separation science because they have been shown to discriminate between positional isomers, functional groups, homologues and enantiomers. This property makes them one of the most useful agents for a wide variety of separations. The main goal of this review is a discussion of somewhat more exotic applications of cyclodextrins to separation methods. Techniques examined in detail include gel electrophoresis, isotachophoresis, isoelectric focusing, preparative scale electrophoretic techniques, thin-layer chromatography, electrochemically modulated liquid chromatography, use of monolithic media in liquid chromatography, microdialysis, separation on hollow fibers, foam flotation enrichment, solid- and liquid-phase extractions, countercurrent chromatography, separation through liquid and composite membranes, and cyclodextrin applications in molecularly imprinted polymers. Since a lot of attention has been paid to use of cyclodextrins in capillary electrophoresis, liquid, gas and supercritical fluid chromatography, these techniques will be only briefly discussed. The second goal of this review is a discussion of a scaling-up the analytical separations to semi-preparative or preparative techniques. It was found that despite a need for large scale separations in the industry, development of these techniques has been somewhat lagging behind development of miniaturized analytical separations. It is hoped that the focus on areas outside more traditional separation applications might stimulate further research.
Reduced power operations in motivic cohomology

In this paper we construct an analog of Steenrod operations in motivic cohomology and prove their basic properties including the Cartan formula, the Adem relations and the realtions to characteristic classes.
Controlling the complexity of menu networks

A common approach to the design of user interfaces for computer systems is the menu selection technique. Each menu frame can be considered a node in an information/action network. The set of nodes and the permissible transitions between them (menu selections) form a directed graph which, in a system of substantial size, can be large and enormously complex. The solution to this problem of unmanageable complexity is the same for menu networks as for programs: the disciplined use of a set of well-defined one-in-one-out structures. This paper defines a set of such structures and offers some guidelines for their use.
Annular and boundary reducing Dehn fillings

Abstract Let M be a simple 3-manifold, i.e. one that contains no essential sphere, disk, annulus or torus, with a torus boundary component ∂0M. One is interested in obtaining upper bounds for the distance (intersection number) Δ (α, β) between slopes α, β on ∂0M such that Dehn filling M along α, β produces manifolds M(α), M(β) that are not simple. There are ten cases, according to whether M(α) (M(β)) contains an essential sphere, disk, annulus or torus. Here we show that if M(α) contains an essential annulus and M(β) contains an essential disk then Δ (α, β)⩽2 . This completes the determination of upper bounds for Δ (α, β) in all ten cases.
COMBINED MODELING OF ACCELERATION, TRANSPORT, AND HYDRODYNAMIC RESPONSE IN SOLAR FLARES: I. THE NUMERICAL MODEL

Acceleration and transport of high-energy particles and fluid dynamics of atmospheric plasma are interrelated aspects of solar flares, but for convenience and simplicity they were artificially separated in the past. We present here self-consistently combined Fokker-Planck modeling of particles and hydrodynamic simulation of flare plasma. Energetic electrons are modeled with the Stanford unified code of acceleration, transport, and radiation, while plasma is modeled with the Naval Research Laboratory flux tube code. We calculated the collisional heating rate directly from the particle transport code, which is more accurate than those in previous studies based on approximate analytical solutions. We repeated the simulation of Mariska et al. with an injection of power law, downward-beamed electrons using the new heating rate. For this case, a ~10% difference was found from their old result. We also used a more realistic spectrum of injected electrons provided by the stochastic acceleration model, which has a smooth transition from a quasi-thermal background at low energies to a nonthermal tail at high energies. The inclusion of low-energy electrons results in relatively more heating in the corona (versus chromosphere) and thus a larger downward heat conduction flux. The interplay of electron heating, conduction, and radiative loss leads to stronger chromospheric evaporation than obtained in previous studies, which had a deficit in low-energy electrons due to an arbitrarily assumed low-energy cutoff. The energy and spatial distributions of energetic electrons and bremsstrahlung photons bear signatures of the changing density distribution caused by chromospheric evaporation. In particular, the density jump at the evaporation front gives rise to enhanced emission, which, in principle, can be imaged by X-ray telescopes. This model can be applied to investigate a variety of high-energy processes in solar, space, and astrophysical plasmas.
The effect of surface adsorption on the hyper-Rayleigh scattering of large and small CdSe nanoparticles

Hyper-Rayleigh scattering is used to compare the effect of the addition of n-butylamine to large (3.2 nm) and small (1.6 nm) CdSe nanoparticles (NPs). It is found that although the adsorption of n-butylamine on large NPs enhances their nonlinear optical response, it has the opposite effect when adsorbed on the small nanoparticles for which the amine adsorption was found previously to induce structural changes. This observation is consistent with an increase in the symmetry of the nanocrystal structure such as would be observed in a phase change from a 4-coordinate wurtzite crystal structure to that of a 6-coordinate zinc-blend form.
Economic development and food production–consumption balance: A growing global challenge

Abstract Rising affluence in major developing countries (principally China and India) and increasing diversion of agricultural resources for energy production (USA and Brazil) sharply increase agricultural resource demand. Food consumption and production changes during development are analyzed using resource-based cereal-equivalent measures. Diet upgrades to livestock products require fivefold increases in per capita food resource use, reflecting a consistent pattern which is only marginally affected by land base. Food consumption increases exceed production during early development, leading to imports. Consumption eventually stabilizes at high incomes, but production falls short in land-scarce countries. Pork and poultry consumption increase the most; less efficient beef and dairy production command a majority of agricultural resources.
The Polls—Trends Public Reactions to Global Health Threats and Infectious Diseases

Over the past two decades, newly emerging infectious dis eases have developed into major global health concerns, sparking intense media coverage, and triggering fears of a global outbreak among public health experts and authorities. This article focuses on trends in American attitudes toward these newly emerged infectious diseases by analyzing poll data over the past 6 years about issues relating to avian flu, severe acute respiratory syndrome, West Nile virus, and anthrax. The polls show that Americans' attention to news coverage seemed to be event driven, peaking when there were new human or animal cases, and decreasing rapidly when the diseases seemed to have been contained. Americans' perceptions of threats were usually the highest in the early stages of ma jor outbreaks. The public became more complacent when the outbreaks seemed to be under control. Both behavioral changes and general knowl edge remained largely constant, suggesting a limited impact of the various informational and awareness campaigns by governmental agencies in the wake of these pandemics.
Complements and Higher Resonance Varieties of Hyperplane Arrangements

Hyperplane arrangements form the geometric counterpart of combinatorial objects such as matroids. The shape of the sequence of Betti numbers of the complement of a hyperplane arrangement is of particular interest in combinatorics, where they are known, up to a sign, as Whitney numbers of the first kind, and appear as the coefficients of chromatic, or characteristic, polynomials. We show that certain combinations, some nonlinear, of these Betti numbers satisfy Schur positivity. At the same time, we study the higher degree resonance varieties of the arrangement. We draw some consequences, using homological algebra results and vector bundles techniques, of the fact that all resonance varieties are determinantal.
Beta limit due to m/n = 2/1 tearing mode onset in the DIII-D hybrid scenario

The performance (?N ? 3, q95 ? 4.4, fBS ? 0.5, H89 > 2) of hybrid scenario plasmas in DIII-D (Luxon 2002 Nucl. Fusion 42 614) is limited by m/n = 2/1 tearing modes. Unlike conventional plasmas (Hender et al 2004 Nucl. Fusion 44 798), the linear dependence scaling of the global beta for onset of the instability with normalized local ion gyroradius is modified as the n = 1 ideal kink beta limit is approached, suggesting that small island neoclassical tearing mode (NTM) threshold physics does not impose the dominant criterion for NTM stability. The hybrid scenario tends to go unstable just at or below the no wall n = 1 ideal kink beta limit of about 4?i. Experimentally 4?i decreases with beta as . Thus the 'ceiling' in beta due to coupling of tearing to the ideal kink comes down as beta is increased. Scaling of the tearing unstable beta that combines both NTM threshold physics and a pole in ?'r due to coupling to the ideal kink is presented.
Signal classification for automatic industrial inspection

Details of a system designed to inspect web-type products are presented. The sensing device used is a laser scanner, and a brief description of the scanner is given. A set of bandpass filters is proposed as feature extracters. The required characteristics of the filters are determined through digital simulation, using feature selection methods. The linear classifier is designed from a set of training signals. Contextual information is used in the classification of signals into good product or into various defective categories. In addition, results of a study on inspection of magnetic tapes and abrasive sheets are described.
Inventories and the Three Phases of the Business Cycle

This article demonstrates that recessions typically are followed by high-growth recovery phases that push output back to its prerecession level. Thus postwar fluctuations in real output in the United States have consisted of three sequential phases rather than two—contractions, high-growth recoveries, and moderate-growth periods following recoveries. Data from before World War II also exhibit this pattern. For the postwar period, the three-phase pattern is shown to reflect swings in inventory investment and suggests that output fluctuations have an important transitory component. The evidence in this article supports DeLong and Summers's output-gaps view and Friedman's “plucking” model view of fluctuations.
Reactive Flow Control of Delta-Wing Vortex

In this paper, the reactive flow control of delta-wing leading-edge vortices using along-core pulse-widthmodulation flow injection is presented. Leading-edge vortices on the upper surface of a delta wing can augment lift. Manipulating breakdown points of leading-edge vortices can effectively change the delta wing’s lift and drag and generate attitude-control torque. In this paper, a black-box dynamic model for active flow control of vortex breakdown points is identified from wind-tunnel data using a model scheduling method. Based on the identified model, a closed-loop active flow controller is developed. Simulation and real-time wind-tunnel test show that the closed-loop controller can effectively manipulate the upper surface pressure of the delta wing, which indicates that the closed-loop controller can effectively control vortex breakdown points.
Middle Ultraviolet Spectroscopy of Pluto and Charon

Abstract The first Pluto's spectrum in the range 2000 to 2500 A has been extracted from the Hubble Space Telescope (HST) archive observations acquired during 24 orbits. Although the spectral intensity is very weak and smaller than that for Titan by a factor of 100, the spectrum has a signal-to-noise ratio of 10–15 at the resolution of 10 A. The mean geometric albedo is almost constant at 0.24 in this range. Observations at different longitudes reveal variations which correlate with the visible lightcurve at 3300–2500 A and become more irregular at the shorter wavelengths. Variable quantities of haze, clouds, and rime may explain the higher variations at 2200–2300 A. A search for gaseous absorptions resulted in upper limits to C 4 H 2 , C 6 H 2 , HC 3 N, and C 4 N 2 . The first three limits impose important constraints to photochemical models of Pluto's atmosphere. The Cameron bands cannot be used for detection of CO on Pluto and Triton because of the very low atmospheric pressures. The first ultraviolet spectra of Charon were extracted from the HST archive observation acquired during 16 orbits. The spectra cover the range 2250–3300 A with a signal-to-noise ratio varying from ≈70 at 3300–2650 A to ≈8 at 2400–2250 A. The geometric albedo of Charon is 0.25 and is almost constant in the measured range. The north south ratio is 1.04±0.02 from 2550 to 3300 A. Comparing the extracted spectra with laboratory spectra of H 2 O, CO 2 , NH 3 , and SO 2 ices, upper limits to concentrations of these species in the ices of Pluto and Charon have been established. However, these limits are high and nonrestrictive.
Symmetry of hydrogen bonds in solution

A classic question regarding hydrogen bonds (H-bonds) concerns their symmetry. Is the hydrogen centered or is it closer to one donor and jumping between them? These possibilities correspond to single- and double-well potentials, respectively. The NMR method of isotopic perturbation can answer this question. It is illustrated with 3-hydroxy-2-phenylpropenal and then applied to dicarboxylate monoanions. The 18 O-induced 13 C NMR splittings signify that their intramolecular H-bonds are asymmetric and that each species is a pair of tautomers, not a single symmetric structure, even though maleate and phthalate are symmetric in crystals. The asymmetry is seen across a wide range of solvents and a wide variety of monoanions, including 2,3-di-tert-butylsuccinate and zwitterionic phthalates. Asymmetry is also seen in monoprotonated 1,8-bis(dimethylamino)-naphthalenediamines, N,N'-diaryl-6-aminofulvene-2-aldimines, and 6-hydroxy-2-formyl-fulvene. The asymmetry is attributed to the disorder of the local environment, establishing an equilibrium between solvatomers. The broader implications of these results regarding the role of solvation in breaking symmetry are discussed. It was prudent to confirm a secondary deuterium isotope effect (IE) on amine basicity by NMR titration of a mixture of PhCH 2 NH 2 and PhCHDNH 2 . The IE is of stereoelectronic origin. It is proposed that symmetric H-bonds can be observed in crystals but not in solution because a disordered environment induces asymmetry, whereas a crystal can guarantee a symmetric environment. The implications for the controversial role of low-barrier H-bonds in enzyme-catalyzed reactions are discussed.
Existence of Hopf subalgebras of GK-dimension two

Abstract Let H be a pointed Hopf algebra over an algebraically closed field of characteristic zero. If H is a domain with finite Gelfand–Kirillov dimension greater than or equal to two, then H contains a Hopf subalgebra of Gelfand–Kirillov dimension two.
Quantum oscillations in electron-doped high-temperature superconductors

Quantum oscillations in hole-doped high-temperature superconductors are difficult to understand within the prevailing views. An emerging idea is that of a putative normal ground state, which appears to be a Fermi liquid with a reconstructed Fermi surface. The oscillations are due to formation of Landau levels. Recently the same oscillations were found in the electron-doped cuprate, ${\text{Nd}}_{2\ensuremath{-}x}{\text{Ce}}_{x}{\text{CuO}}_{4}$, in the optimal to overdoped regime. Although these electron-doped nonstoichiometric materials are naturally more disordered, they strikingly complement the hole-doped cuprates. Here we provide an explanation of these observations from the perspective of density waves using a powerful transfer matrix method to compute the conductance as a function of the magnetic field.
A discipline of multiprogramming

The main software challenge in developing application programs during the 1960s and the 1970s was that the programs had to operate within limited resources, i.e., slow processors, small memories, and limited disk capacities. Application programming became far more widespread during the 1980s because of the falling prices of hardware (which meant that more processing power and storage were available for the same cost) and a better understanding of the application programming process. However, most applications still ran on mainframes or over a cluster of machines in a local-area network; truly distributed applications that ran over wide-area networks were few because of the latency and bandwidth limitations of long-haul communication. The 1990s saw great strides in broad-band communication, and the World Wide Web provides a giant repository of information. This combination promises development of a new generation of distributed applications, ranging from mundane office tasks —e.g., planning a meeting by reading the calendars of the participants— to real-time distributed control and coordination of hundreds of machines —e.g., as would be required in a recovery effort from an earthquake.
Designing environmentally sustainable electronic cooling systems using exergo‐thermo‐volumes

Thermo-volumes allow the design engineer to expediently understand the thermal resistance of a given cooling solution (an indicator of performance) along with its flow resistance (an indicator of the pumping power, or energy consumption, which will be required by the fluid handler). In the present work, we expand upon thermo-volumes by including the lifetime exergy cost (in units of Joules of availability destroyed) as a means to enable the consideration of resource consumption (and thus the environmental sustainability) of the cooling solution. To achieve these exergo-thermo-volumes, we reinterpret previous definitions of thermo-volumes in terms of the entropy generated during heat transfer and fluid flow. The Guoy–Stodola theorem is used to convert this entropy generation into an ‘operational’ exergy loss. Next, based on the material choice and assembly processes used in creating the product, an embedded exergy consumption that accounts for the amount of exergy destroyed during extraction, transportation and disposal of the material is attached to the operational exergy loss. Thus, the total ‘cradle-to-cradle’ exergy loss of the solution is devised. In this framework, the optimal solution will be that which destroys the minimal amount of exergy. Correspondingly, instead of relying upon the coefficient of performance (which is focused on operational consumption), we propose evaluation of cooling solutions in terms of the heat removal capacity per unit lifetime exergy consumption. The paper concludes by illustrating applicability of the method to the design of an enterprise server. It should be noted that although the paper is focused on electronics cooling solutions, the methodology is designed to be sufficiently general for use in any thermal management application. Copyright © 2009 John Wiley & Sons, Ltd.
Leading power corrections in QCD: From renormalons to phenomenology

We consider 1Q corrections to hard processes in QCD where Q is a large mass scale, concentrating on shape variables in e+e− annihilation. While the evidence for such corrections can be and has been established by means of the renormalon technique, theory can be confronted with experiment only after clarifying the properties of the corresponding non-perturbative contribution. We list predictions based on the universality of the 1Q terms, and compare them with the existing data. We also identify the scale of the non-perturbative contributions in terms of jet masses.