cssi/SciSciGPT-SciSciNet huggingface dataset:
Variance Function Estimation in High-dimensions

We consider the high-dimensional heteroscedastic regression model, where the mean and the log variance are modeled as a linear combination of input variables. Existing literature on high-dimensional linear regression models has largely ignored non-constant error variances, even though they commonly occur in a variety of applications ranging from biostatistics to finance. In this paper we study a class of nonconvex penalized pseudolikelihood estimators for both the mean and variance parameters. We show that the Heteroscedastic Iterative Penalized Pseudolikelihood Optimizer (HIPPO) achieves the oracle property, that is, we prove that the rates of convergence are the same as if the true model was known. We demonstrate numerical properties of the procedure on a simulation study and real world data.
Higher-order finite-difference formulation of periodic Orbital-free Density Functional Theory

We present a real-space formulation and higher-order finite-difference implementation of periodic Orbital-free Density Functional Theory (OF-DFT). Specifically, utilizing a local reformulation of the electrostatic and kernel terms, we develop a generalized framework for performing OF-DFT simulations with different variants of the electronic kinetic energy. In particular, we propose a self-consistent field (SCF) type fixed-point method for calculations involving linear-response kinetic energy functionals. In this framework, evaluation of both the electronic ground-state and forces on the nuclei are amenable to computations that scale linearly with the number of atoms. We develop a parallel implementation of this formulation using the finite-difference discretization. We demonstrate that higher-order finite-differences can achieve relatively large convergence rates with respect to mesh-size in both the energies and forces. Additionally, we establish that the fixed-point iteration converges rapidly, and that it can be further accelerated using extrapolation techniques like Anderson's mixing. We validate the accuracy of the results by comparing the energies and forces with plane-wave methods for selected examples, including the vacancy formation energy in Aluminum. Overall, the suitability of the proposed formulation for scalable high performance computing makes it an attractive choice for large-scale OF-DFT calculations consisting of thousands of atoms.
Optimal Program-Size Complexity for Self-Assembly at Temperature 1 in 3D

Working in a three-dimensional variant of Winfree's abstract Tile Assembly Model, we show that, for all $$N \in \mathbb {N}$$N∈N, there is a tile set that uniquely self-assembles into an $$N \times N$$N×N square shape at temperature 1 with optimal program-size complexity of $$O\log N / \log \log N$$OlogN/loglogN the program-size complexity, also known as tile complexity, of a shape is the minimum number of unique tile types required to uniquely self-assemble it. Moreover, our construction is "just barely" 3D in the sense that it works even when the placement of tiles is restricted to the $$z = 0$$z=0 and $$z = 1$$z=1 planes. This result affirmatively answers an open question from Cook, Fu, Schweller SODA 2011. To achieve this result, we develop a general 3D temperature 1 optimal encoding construction, reminiscent of the 2D temperature 2 optimal encoding construction of Soloveichik and Winfree SICOMP 2007, and perhaps of independent interest.
Firms’ locational choice and infrastructure development in Rwanda

Agglomeration economies are among the most important factors to increase firm productivity. However, there is little evidence supportive of this in Africa. By applying the conditional and nested logit models, this paper examines the relationship between firm locations and infrastructure accessibility in Rwanda. It is found that agglomeration economies matter to even one of the smallest countries in Africa. It is also found that infrastructure availability has an important role in affecting the firm location decision. Electricity access and transport connectivity to the domestic and international markets are found to be important to attract new investment. In addition, the quality of local labor supplied, measured by educational attainment, is found as an important determinant of firm location, while the effect of labor costs remains inconclusive.
Numerical Simulations of Magnetic Fields in Astrophysical Turbulence

The generation and evolution of astrophysical magnetic fields occurs largely through the action of turbulence. In many situations, the magnetic field is strong enough to influence many important properties of turbulence itself. Numerical simulation of magnetized turbulence is especially challenging in the astrophysical regime because of the high magnetic Reynolds numbers involved, but some aspects of this difficulty can be avoided in weakly ionized systems.
Fifty years of fat: news coverage of trends that predate obesity prevalence

Obesity prevalence has risen in fifty years. While people generally expect media mentions of health risks like obesity prevalence to follow health risk trends, food consumption trends may precede obesity prevalence trends. Therefore, this research investigates whether media mentions of food predate obesity prevalence. Fifty years of non-advertising articles in the New York Times (and 17 years for the London Times) are coded for the mention of less healthy (5 salty and 5 sweet snacks) and healthy (5 fruits and 5 vegetables) food items by year and then associated with annual obesity prevalence in subsequent years. Time-series generalized linear models test whether food-related mentions predate or postdate obesity prevalence in each country. United States obesity prevalence is positively associated with New York Times mentions of sweet snacks (b = 55.2, CI = 42.4 to 68.1, p = .000) and negatively associated with mentions of fruits (b = −71.28, CI −91.5 to −51.1, p = .000) and vegetables (b = −13.6, CI = −17.5 to −9.6, p = .000). Similar results are found for the United Kingdom and The London Times. Importantly, the “obesity followed mentions” models are stronger than the “obesity preceded mentions” models. It may be possible to estimate a nation’s future obesity prevalence (e.g., three years from now) based on how frequently national media mention sweet snacks (positively related) and vegetables or fruits (negatively related) today. This may provide public health officials and epidemiologists with new tools to more quickly assess the effectiveness of current obesity interventions based on what is mentioned in the media today.
Slip on faults in the Imperial Valley triggered by the 4 April 2010 Mw 7.2 El Mayor‐Cucapah earthquake revealed by InSAR

[1] Radar interferometry (InSAR), field measurements and creepmeters reveal surface slip on multiple faults in the Imperial Valley triggered by the main shock of the 4 April 2010 El Mayor-Cucapah Mw 7.2 earthquake. Co-seismic offsets occurred on the San Andreas, Superstition Hills, Imperial, Elmore Ranch, Wienert, Coyote Creek, Elsinore, Yuha, and several minor faults near the town of Ocotillo at the northern end of the mainshock rupture. We documented right-lateral slip (<40 mm) on northwest-striking faults and left-lateral slip (<40 mm) on southwest-striking faults. Slip occurred on 15-km- and 20-km-long segments of the San Andreas Fault in the Mecca Hills (≤50 mm) and Durmid Hill (≤10 mm) respectively, and on 25 km of the Superstition Hills Fault (≤37 mm). Field measurements of slip on the Superstition Hills Fault agree with InSAR and creepmeter measurements to within a few millimeters. Dislocation models of the InSAR data from the Superstition Hills Fault confirm that creep in this sequence, as in previous slip events, is confined to shallow depths (<3 km).
Inverse magnetic catalysis in holographic models of QCD

We study the effect of magnetic field B on the critical temperature T c of the confinement-deconfinement phase transition in hard-wall AdS/QCD, and holographic duals of flavored and unflavored $$ \mathcal{N}=4 $$ super-Yang Mills theories on $$ {\mathbb{R}}^3\times {\mathrm{S}}^1 $$ . For all of the holographic models, we find that T c (B) decreases with increasing magnetic field B ≪ T 2, consistent with the inverse magnetic catalysis recently observed in lattice QCD for B ≲ 1 GeV2. We also predict that, for large magnetic field B ≫ T 2, the critical temperature T c (B), eventually, starts to increase with increasing magnetic field B ≫ T 2 and asymptotes to a constant value.
Tessellation of quadratic elements

Topology-based methods have been successfully used for the analysis and visualization of piecewise-linear functions defined on triangle meshes. This paper describes a mechanism for extending these methods to piecewise-quadratic functions defined on triangulations of surfaces. Each triangular patch is tessellated into monotone regions, so that existing algorithms for computing topological representations of piecewise-linear functions may be applied directly to piecewise-quadratic functions. In particular, the tessellation is used for computing the Reeb graph, which provides a succinct representation of level sets of the function.
Interstitial He and Ne in Nanotube Bundles

We explore the properties of atoms confined to the interstitial regions within a carbon nanotube bundle. We find that He and Ne atoms are of ideal size for physisorption interactions, so that their binding energies are much greater there than on planar surfaces of any known material. Hence high density phases exist at even small vapor pressure. There can result extraordinary anisotropic liquids or crystalline phases, depending on the magnitude of the corrugation within the interstitial channels.
Solid-state Raman lasers

Summary form only given. In summary, topics discussed included: intracavity Raman beam cleanup, temporal dynamics; coupled-cavity mode-matching, power-scaling techniques, thermally stationary cavity design, aberration compensation, Raman gain and output coupling control, and multimode buildup dynamics.
Vocational schooling, labor market outcomes, and college entry

This paper examines the differentiated outcomes of vocational and general secondary academic education, particularly in terms of employment opportunities, labor market earnings, and access to tertiary education in Indonesia. With data from a panel of two waves of the Indonesia Family Life Survey in 1997 and 2000, the paper tracks a cohort of high school students in 1997 to examine their schooling and employment status in 2000. The findings demonstrate that: (1) attendance at vocational secondary schools results in neither market advantage nor disadvantage in terms of employment opportunities and/or earnings premium; (2) attendance at vocational schools leads to significantly lower academic achievement as measured by national test scores; and (3) There is no stigma attached to attendance at vocational schools that results in a disadvantage in access to tertiary education; rather, it is the lower academic achievement associated with attendance at vocational school that lowers the likelihood of entering college. The empirical approach of this paper addresses two limitations of the existing literature in this area. First, it takes into account the observation censoring issue due to college entry when evaluating labor market outcomes of secondary school graduates. Second, using an instrumental variable approach, the paper also treats endogeneity of household choice of vocational versus academic track of secondary education, teasing out the net effect of secondary school choice on labor market and schooling outcomes.
The Sebastiani–Thom Isomorphism in the Derived Category

We prove that the Sebastiani–Thom isomorphism for Milnor fibres and their monodromies exists as a natural isomorphism between vanishing cycles in the derived category.
Enhancing the Capacity of School Nurses to Reduce Excessive Anxiety in Children: Development of the CALM Intervention

Problem Excessive anxiety is among the most common psychiatric problems facing youth. Because anxious youth tend to have somatic complaints, many seek help from the school nurse. Thus, school nurses are in an ideal position to provide early intervention. This study addresses this problem and describes the plans to develop and test a new intervention (Child Anxiety Learning Modules; CALM), delivered by school nurses, to reduce child anxiety and improve academic functioning. Methods An iterative development process including consultation with an expert panel, two open trials, and a pilot randomized controlled study comparing CALM to usual care is proposed. Feedback will be solicited from all participants during each phase and data on outcome measures will be provided by children, parents, teachers, and independent evaluators. Findings Data will be collected on intervention satisfaction and feasibility. Primary outcomes that include child anxiety symptoms, classroom behavior, and school performance (e.g., attendance, grades, standardized test scores) will be collected at pre- and post-interventions and at a 3-month follow-up evaluation. Conclusions Pediatric anxiety is a common problem that school nurses frequently encounter. Consequently, they are well positioned to play a key role in enhancing access to behavioral health interventions to reduce anxiety and may therefore make a significant positive public health impact.
Differentiating induced and natural seismicity using space‐time‐magnitude statistics applied to the Coso Geothermal field

A remarkable characteristic of earthquakes is their clustering in time and space, displaying their self-similarity. It remains to be tested if natural and induced earthquakes share the same behavior. We study natural and induced earthquakes comparatively in the same tectonic setting at the Coso Geothermal Field. Covering the preproduction and coproduction periods from 1981 to 2013, we analyze interevent times, spatial dimension, and frequency-size distributions for natural and induced earthquakes. Individually, these distributions are statistically indistinguishable. Determining the distribution of nearest neighbor distances in a combined space-time-magnitude metric, lets us identify clear differences between both kinds of seismicity. Compared to natural earthquakes, induced earthquakes feature a larger population of background seismicity and nearest neighbors at large magnitude rescaled times and small magnitude rescaled distances. Local stress perturbations induced by field operations appear to be strong enough to drive local faults through several seismic cycles and reactivate them after time periods on the order of a year.
EXAMINATION OF THE PREVALENCE OF STIMULUS OVERSELECTIVITY IN CHILDREN WITH ASD

Many individuals with autism spectrum disorders (ASD) display stimulus overselectivity, wherein a subset of relevant components in a compound stimulus controls responding, which impairs discrimination learning. The original experimental research on stimulus overselectivity in ASD was conducted several decades ago; however, interventions for children with ASD now typically include programming to target conditional discriminations in ways that might minimize the prevalence of stimulus overselectivity. The present study assessed 42 children who had been diagnosed or educationally identified with ASD using a discrimination learning assessment. Of these 42 children, 19% displayed overselective responding, which is a lower percentage than that seen in early research. Possible explanations for this decreased percentage, implications for intervention, and future directions for research are discussed.
A micromechanics model for electrical conduction in isotropically conductive adhesives during curing

A 3-D electrical conduction model for isotropically conductive adhesives with spherical particles was developed to simulate the curing process. A microstructure model of a conductive adhesive block was generated to describe the positions and connections of the conductive fillers. The bulk resistance of the conductive adhesive is mainly contributed by the contact resistances between connected particles. The contact resistance consists of constriction resistance and tunnel resistance, which depend on contact load, filler material properties and contact areas. A finite element analysis of a representative volume element was conducted to simulate the process of shrinkage caused by the curing process of the polymer matrix. The resulted contact radius was incorporated in the calculation of contact resistances between conductive particles, the bulk resistance was then calculated of the resistor network formed by all particle connections. The result of bulk resistivity change with respect to shrinkage was presented and compared with experimental results.
The Logic Of Only Knowing As A Unified Framework For Non-Monotonic Reasoning

We propose to use the logic of only knowing (OL) by Levesque [10] as a unified framework that encompasses various non-monotonic formalisms and logic programming. OL is a modal logic which can be used to formalize an agent's introspective reasoning and to answer epistemic queries to databases. The OL logic allows one to formally express the statement “α is all I know” (in symbols, Oα) and to perform inferencing based on only-knowing, which is very useful for commonsense reasoning. Another nice thing about the OL logic is that it has a clear model-theoretic semantics and a simple proof theory, which is sound for the quantificational case, and both sound and complete for the prepositional case. We establish the relations between OL and various non-monotonic logics (such as default logic, circumscription) and logic programming, thus extending the existing works relating the OL logic with other non-monotonic reasoning formalisms (e.g., Levesque showed that autoepistemic logic can be embeded in OL). This is accomplished by finding the connection between OL and MBNF, the logic of Minimal Belief and Negation as Failure proposed by Lifschitz [12, 13], which is known to have close relationship with logic programming and other non-monotonic logics. Our results show that OL can be used as a unified framework to compare different non-monotonic formalisms based on the same domain.
More Relatively-Poor People in a Less Absolutely-Poor World

Relative deprivation, shame and social exclusion can matter to the welfare of people everywhere. The authors argue that such social effects on welfare call for a reconsideration of how we assess global poverty, but they do not support standard measures of relative poverty. The paper argues instead for using a weakly-relative measure as the upper-bound complement to the lower-bound provided by a standard absolute measure. New estimates of global poverty are presented, drawing on 850 household surveys spanning 125 countries over 1981-2008. The absolute line is $1.25 a day at 2005 prices, while the relative line rises with the mean, at a gradient of 1:2 above $1.25 a day. The authors show that these parameter choices are consistent with cross-country data on national poverty lines. The results indicate that the incidence of both absolute and weakly-relative poverty in the developing world has been falling since the 1990s, but more slowly for the relative measure. While the number of absolutely poor has fallen, the number of relatively poor has changed little since the 1990s, and is higher in 2008 than 1981.
How Economists Can Get Alife

This paper presents a summary overview of the fast-developing field of "artificial life," stressing aspects that seem especially relevant for the study of decentralized market economies. In particular, recent artificial life work combining evolutionary game theory with preferential partner selection is described in some detail. This work is currently being applied to the endogenous formation and evolution of trade networks.
A Generating Function Approach to Counting Theorems for Square-Free Polynomials and Maximal Tori

A recent paper of Church, Ellenberg, and Farb uses topology and representation theory of the symmetric group to prove enumerative results about square-free polynomials and F-stable maximal tori of \({GL_n(\overline{F}_q)}\). In this note, we use generating functions to give short, elementary proofs of some of their results, and some extensions.
Export diversification and economic growth

Export diversification can lead to higher growth. Developing countries should diversify their exports since this can, for example, help them to overcome export instability or the negative impact of terms of trade in primary products. The process of economic development is typically a process of structural transformation where countries move from producing 'poor-country goods' to 'rich-country goods.' Export diversification does play an important role in this process. The author also provides robust empirical evidence of a positive effect of export diversification on per capita income growth. This effect is potentially nonlinear with developing countries benefiting from diversifying their exports in contrast to the most advanced countries that perform better with export specialization.
The Kennicutt–Schmidt star formation relation at z∼ 2

Recent observations of excited CO emission lines from z ∼ 2 disc galaxies have shed light on the SFR ∝ p N relation at high z via observed Σ SFR -Σ α COJ=2-1 and Σ SFR -Σ α COJ=3-2 relations. Here, we describe a novel methodology for utilizing these observations of high-excitation CO to derive the underlying Schmidt (SFR ∝ p N ) relationship. To do this requires an understanding of the potential effects of differential CO excitation with SFR. If the most heavily star-forming galaxies have a larger fraction of their gas in highly excited CO states than the lower SFR galaxies, then the observed molecular Kennicutt-Schmidt index, α, will be less than the underlying SFR oc p N index, N. Utilizing a combination of SPH models of galaxy evolution and molecular line radiative transfer, we present the first calculations of CO excitation in z ~ 2 disc galaxies with the aim of developing a mapping between various observed Σ SFR -Σ α CO relationships and the underlying SFR ∝ ρ N relation. We find that even in relatively luminous z ∼ 2 discs, differential excitation does indeed exist, resulting in α < N for highly excited CO lines. This means that an observed (e.g.) Σ SFR -Σ α COJ=3-2 relation does not map linearly to a Σ SFR -Σ α H2 relation. We utilize our model results to provide a mapping from α to N for the range of Schmidt indices N = 1-2. By comparing to recent observational surveys, we find that the observed Σ SFR -Σ α COJ=2-1 and Σ SFR -Σ α COJ=3-2 relations suggest that an underlying SFR ∝ ρ 1.5 relation describes z ∼ 2 disc galaxies.
South Sudan's infrastructure : a continental perspective

This study is a product of the Africa Infrastructure Country Diagnostic (AICD), a project designed to expand the world's knowledge of physical infrastructure in Africa. AICD provides a baseline against which future improvements in infrastructure services can be measured, making it possible to monitor the results achieved from donor support. It also offers a solid empirical foundation for prioritizing investments and designing policy reforms in Africa's infrastructure sectors. The AICD is based on an unprecedented effort to collect detailed economic and technical data on African infrastructure. The project has produced a series of original reports on public expenditure, spending needs, and sector performance in each of the main infrastructure sectors, including energy, information and communication technologies, irrigation, transport, and water and sanitation. This report presents the key AICD findings for South Sudan, allowing the country's infrastructure situation to be benchmarked against that of its African peers. South Sudan is a newly independent country, affected by conflict, endowed with oil, but poor in terms of infrastructure and economic development. Because of these factors, both low-income, fragile states and resource-rich benchmarks will be used to evaluate its performance. Detailed comparisons will also be made with immediate regional neighbors in the East African Community (EAC).
A curse of comparison ? evidence on reference groups for relative income concerns

This paper proposes that individuals care about the relative income of proximate reference groups. Making use of self-reported life satisfaction as a proxy for unobservable utility, the relative income of siblings is tested for relevance as a reference point for new sample data from Venezuela. Having greater perceived income than one's siblings is found to be positively linked to individual life satisfaction. This evidence supplements the scarce economic research on reference groups, supporting the hypothesis that individuals with proximate characteristics and resembling opportunities in life serve as points of comparison.
The Galactic Center Isolated Nonthermal Filaments as Analogs of Cometary Plasma Tails

We propose a model for the origin of the isolated nonthermal filaments observed at the Galactic center based on an analogy to cometary plasma tails. We invoke the interaction between a large-scale magnetized galactic wind and embedded molecular clouds. As the advected wind magnetic field encounters a dense molecular cloud, it is impeded and drapes around the cloud, ultimately forming a current sheet in the wake. This draped field is further stretched by the wind flow into a long, thin filament the aspect ratio of which is determined by the balance between the dynamical wind and amplified magnetic field pressures. The key feature of this cometary model is that the filaments are dynamic configurations, and not static structures. As such, they are local amplifications of an otherwise weak field and not directly connected to any static global field. The derived field strengths for the wind and wake are consistent with observational estimates. Finally, the observed synchrotron emission is naturally explained by the acceleration of electrons to high energy by plasma and MHD turbulence generated in the cloud wake.
Damping of nodal fermions caused by a dissipative mode

Abstract Using a d x 2 − y 2 superconductor in 2+1 dimensions we show that the Nambu–Goldstone fluctuations are replaced by dissipative excitations. We find that the nodal quasi-particles damping is caused by the strong dissipative excitations near the nodal points. As a result we find that the scattering rates are linear in frequency and not cubic as predicted in the literature for the “d” wave superconductors. Our results explain the recent angle resolved photoemission spectroscopy and optical conductivity in the BSCCO high T c compounds.
An electrically-small, 3-D cube antenna fabricated with additive manufacturing

This paper presents the design of an electrically small, 3-D cube antenna that is fabricated using laser-based layer-by-Iayer stereolithography processing (SLA). The antenna consists of a balun and a half-wave dipole with meandered-line portions, all of which are patterned on the surface of a cube. The antenna operational frequency is 2.45 GHz and its measured 10 dB return loss bandwidth is 3.75%. Ka of the proposed design is 0.73 and its measured gain is -0.5 dBi. The gain is decreased by 2.5 dB compared with a previous prototype made with printed circuit board (PCB) technology using a commercial microwave substrate. However, the SLA fabrication approach significantly improves the manufacturing repeatability.
Possibility of a large evolutionary correction to the magnitude-redshift relation

Galactic evolution may be rapid enough to reconcile the observed magnitude-redshift relation with cosmological models of acceptably great age and low density, in spite of recent evidence to the contrary. Previous treatments of this subject have suffered from use of wrong quantities as the evolutionary correction, and from lack of generality in galactic models. A range of giant elliptical galaxies can be synthesized which are compatible with the available photometry, including Oke and Sandage's (1968) observations of a slow rate of change of color B-V. One such model galaxy is discussed which evolves sufficiently rapidly at short wavelengths to provide an evolutionary correction of several tenths of a magnitude at redshift 0.46.
Interfacial area measurements in subcooled flow boiling

The purpose of the present study was to measure two-phase parameters in subcooled flow boiling. These parameters include void fraction distribution, interfacial area concentration distribution, Sauter mean diameter, and the interfacial velocity. A literature review was conducted and the results show that only three researchers have made local measurements in the subcooled boiling region. None of the previous have included results for interfacial area concentration distribution. To make these measurements an experimental facility was constructed that allows insertion of advanced local two-phase flow instrumentation. Experiments were performed for a number of conditions at atmospheric pressure.
Hand-to-mouth consumers and asset prices

Many consumers seem to lead a hand-to-mouth existence: they simply consume their current income. This may be the result of unsophisticated behavior (non-optimizing, or ‘rule-of-thumb’ consumers), or the reflection of an inability to trade in asset markets due to infinite transactions costs. The objective of this paper is to explore, in a very simple model, the implications for equilibrium asset prices of the presence of hand-to-mouth consumers. I will establish that allowing for the existence of hand-to-mouth consumers contributes, under plausible assumptions, to the resolution of the equity premium puzzle’ and of the riskfree rate puzzle. As a consequence, the same phenomenon - hand-to-mouth consumption - which Campbell and Mankiw (1989) have shown to be crucial to the description of the time-series behavior of aggregate consumption has the potential of explaining asset market data (...).
On C∗-algebras and K-theory for infinite-dimensional Fredholm manifolds

Abstract Let M be a smooth Fredholm manifold modeled on a separable infinite-dimensional Euclidean space E with Riemannian metric g . Given an augmented Fredholm filtration F of M by finite-dimensional submanifolds { M n } n = k ∞ , we associate to the triple ( M , g , F ) a non-commutative direct limit C ∗ -algebra A ( M , g , F ) = lim → A ( M n ) that can play the role of the algebra of functions vanishing at infinity on the non-locally compact space M . The C ∗ -algebra A ( E ) , as constructed by Higson–Kasparov–Trout for their Bott periodicity theorem, is isomorphic to our construction when M = E . If M has an oriented Spin q -structure ( 1 ⩽ q ⩽ ∞ ) , then the K -theory of this C ∗ -algebra is the same (with dimension shift) as the topological K -theory of M defined by Mukherjea. Furthermore, there is a Poincare duality isomorphism of this K -theory of M with the compactly supported K -homology of M , just as in the finite-dimensional spin setting.
Multiple operator integrals and higher operator derivatives

Abstract In this paper we consider the problem of the existence of higher derivatives of the function t ↦ ϕ ( A + tK ) , where ϕ is a function on the real line, A is a self-adjoint operator, and K is a bounded self-adjoint operator. We improve earlier results by Sten’kin. In order to do this, we give a new approach to multiple operator integrals. This approach improves the earlier approach given by Sten’kin. We also consider a similar problem for unitary operators.
Anomalous Thermal Expansion in the Square-Net Compounds RE4TGe8 (RE = Yb, Gd; T = Cr–Ni, Ag)

The family of materials RE4TGe8 (RE = Yb, Gd; T = transition metal) exhibits directional zero thermal expansion (ZTE) via a process that is associated with the linking of planar square nets in the third dimension. The Ge square nets in these compounds exhibit commensurate long-range modulations similar to those observed in charge-density-wave compounds. The ZTE is manifested in the plane of the square nets from 10 to 300 K with negligible volume expansion below ∼160 K. The specific atomic arrangement in RE4TGe8 enables a Poisson-like mechanism that allows the structure to contract along one direction as it expands only slightly in the perpendicular direction.
Hyperconjugation in hydrocarbons: Not just a “mild sort of conjugation”

This article emphasizes two underappreciated aspects of hyperconjugation in hydrocarbons, two-way hyperconjugation and hyperconjugation in tight spaces. Nonplanar polyenes (e.g., cyclooctatetraene (D 2d ), biphenyl (D 2 ), styrene (C 1 )), the nonplanar rotational transition states (TSs) of planar polyenes (e.g., perpendicular 1,3-butadiene), as well as the larger nonplanar Huckel or Mobius annulenes, are stabilized by effective σ-electron delocal- ization (involving either the C-C or C-H bonds) via two-way hyperconjugation. The collec- tive consequence of two-way hyperconjugation in molecules can be nearly as stabilizing as π-conjugation effects in planar polyenes. Reexamination of the σ- vs. π-bond strength of ethylene results in surprising counterintuitive insights. Strained rings and cages (e.g., cyclo- propane and tetrahedrane derivatives, the cubyl cation, etc.) can foster unexpectedly large hyperconjugation stabilizations due to their highly deformed ring angles. The thermochemi- cal stabilities of these species rely on a fine balance between their opposing destabilizing geometrical features and stabilizing hyperconjugative effects in tight spaces (adjustable via substituent effects). We hope to help dispel chemists' prejudice in viewing hyperconjugation as merely a "mild" effect with unimportant consequences for interpreting the structures and energies of molecules.
An Improved Measurement of Electron Antineutrino Disappearance at Daya Bay

Abstract The theory of neutrino oscillations explains changes in neutrino flavor, count rates, and spectra from solar, atmospheric, accelerator, and reactor neutrinos. These oscillations are characterized by three mixing angles and two mass-squared differences. The solar mixing angle, θ 12 , and the atmospheric mixing angle, θ 23 , have been well measured, but until recently the neutrino mixing angle θ 13 was not well known. The Daya Bay experiment, located northeast of Hong Kong at the Guangdong Nuclear Power Complex in China, has made a precise measurement of electron antineutrino disappearance using six functionally-identical gadolinium-doped liquid scintillator-based detectors at three sites with distances between 364 and 1900 meters from six reactor cores. This proceeding describes the Daya Bay updated result, using 127 days of good run time collected between December 24, 2011 and May 11, 2012. For the far site, the ratio of the observed number of events to the expected number of events assuming no neutrino oscillation is 0.944 ± 0.007 (stat) ± 0.003 (syst) . A fit for θ 13 in the three-neutrino framework yields sin 2 2 θ 13 = 0.089 ± 0.010 (stat) ± 0.005 (syst) .
Perturbed electroweak strings and fermion zero modes

Abstract The effect of perturbations of electroweak strings on quark zero modes is studied in 2+1 and 3+1 dimensions. As first discovered by Naculich, it is found that the bosonic perturbations that destabilize the string give a mass to the zero modes and also lift their degeneracy. The effect of the zero modes on the stability of the string is discussed qualitatively and, based on general arguments, we conjecture that the fermionic vacuum instability found by Naculich should lead to a distortion of the bosonic string but not be responsible for decay.
PRESTO: feedback-driven data management in sensor networks

This paper presents PRESTO, a novel two-tier sensor data management architecture comprising proxies and sensors that cooperate with one another for acquiring data and processing queries. PRESTO proxies construct time-series models of observed trends in the sensor data and transmit the parameters of the model to sensors. Sensors check sensed data with model-predicted values and transmit only deviations from the predictions back to the proxy. Such a model-driven push approach is energy-efficient, while ensuring that anomalous data trends are never missed. In addition to supporting queries on current data, PRESTO also supports queries on historical data using interpolation and local archival at sensors. PRESTO can adapt model and system parameters to data and query dynamics to further extract energy savings. We have implemented PRESTO on a sensor testbed comprising Intel Stargates and Telos Motes. Our experiments show that in a temperature monitoring application, PRESTO yields one to two orders of magnitude reduction in energy requirements over on-demand, proactive or model-driven pull approaches. PRESTO also results in an order of magnitude reduction in query latency in a 1% duty-cycled five hop sensor network over a system that forwards all queries to remote sensor nodes.
Race, politics, and punishment

This paper empirically evaluates two competing theories of electoral accountability in the context of New Orleans’ 2006 mayoral election. According to the democratic efficiency theory, voters can successfully punish ineffective political agents by removing them from office. In contrast, the public choice theory argues that the bundled nature of political goods prevents voters from successfully holding ineffective politicians accountable. We find that although there is limited support for the punishment effect predicted by the democratic efficiency theory, this effect is overwhelmed by the fact that the bundle of goods politicians offer contains elements that pull in opposing directions. This prevents the punishment effect from having any real impact, leading to democratic failure. Our results support the public choice theory of electoral (un)accountability.
What the Seller Won't Tell You: Persuasion and Disclosure in Markets

Imagine that you are considering an investment in a new public offering of a firm's shares. The firm's officers make a presentation that includes an audited financial statement, an earnings forecast reviewed by its prestigious investment bankers, and an impressive demonstration of its new technology. Or suppose that you are buying a new furnace to replace an old one that is not working well. The salesman displays a chart showing that the projected total life-cycle cost of one particular model, including capital costs and fuel usage over the projected lifetime of the furnace, is lower than that of some competing models you have considered. This paper reviews the theoretical arguments about how sellers disclose information in an attempt to encourage buyers, and the potential role for regulation in encouraging efficient disclosure of information. How well does a system of private reporting work? When should we expect all the relevant information to be reported? If testing and reporting by the seller are costly, will too little testing and reporting be done? Or too much? When some information is withheld, what sort of information is withheld? How do rational buyers respond to such withholding? How are prices and welfare affected? What role is there for laws and regulations to improve the functioning of markets? We address these questions by studying the theory of persuasion games -- games in which one or more sellers provide verifiable information to buyers to influence the actions they take.
On the supposed anticorrelation of solar polar and equatorial rotation rates

Howard and Harvey (1970) analyzed Mt. Wilson Doppler shifts to obtain a daily measure of the Sun's differential rotation. The data were fitted to give an angular velocity of the form ω = a + b sin2B + c sin4B (B = heliographic latitude). Changes in a, b, c were found to be correlated (Howard and Harvey, 1970). Yoshimura (1972) used the anticorrelation of the b and c parameters to infer the existence of large-scale convection. Wolff (1975) used the b-c anticorrelation and a weak correlation between a and b to infer that variations of the Sun's polar and equatorial rotation rates are anticorrelated. In this paper, the anticorrelation of b and c is shown to be due to numerical coupling.
SOLUBILITY OF COLORED GLAZES IN ORGANIC ACIDS

The purpose of this study was to determine primarily which, if any, of the glazes tested constituted a health hazard because of lead or other toxic oxides which might be dissolved from them; and, secondarily, to develop suitable test procedures for future control work. A conference of representatives of the U. S. Potters Association, the Food and Drug Administration of the Department of Agriculture, and the National Bureau of Standards was held, and a series of accelerated and simulative service tests was outlined. These tests were made on specimens from six cooperating manufacturers. It was shown that the lead extracted by pouring either hot, distilled vinegar (5% acetic acid) or an 0.5% solution of citric acid in a cup and leaving it to cool in contact with the glaze for 1/2 hr. would be as much, or more, than the lead normally extracted by jams and fruit juices. With the same or a similar test procedure, a citric-acid solution of 10% strength may be required to indicate how much lead might be taken up by lemonade or vinegar. The results also indicate that glazes of one color only, among those tested, constitute a probable health hazard. Two other glazes from one manufacturer, however, were found to be marginal, and a third may cause trouble if indicated corrective measures, such as a preliminary acid wash, should be neglected by the manufacturer.
Implementation of an adaptive algorithm for Richardson's method

Abstract We discuss the implementation of an adaptive algorithm proposed by one of us. The algorithm is a hybrid of the gmres method and Richardson's method. Richardson's method ( RM ) depends on a set of parameters that are computed by minimizing the L 2 norm of a polynomial over the convex hull of eigenvalues. Execution of GMRES yields not only an approximate solution but also the approximate convex hull. RM is used to avoid storing and working with a large number of vectors as GMRES often requires. This method is also advantageous for the solution of large problems. We consider several test problems and compare our algorithm primarily with the conjugate-gradient-squared algorithm, but also with GMRES and to CG (applied to the normal equations). For many (test) problems our algorithm takes roughly 50 percent more work than the conjugate-gradient-squared algorithm, although if the matrix is either preconditioned or indefinite, our algorithm is more efficient. However, our algorithm currently imposes an undesirable burden on the user, who is invited to consider a variety of numerical parameters to manipulate, such as the number of steps of rm , in order to enhance performance: the values we suggest are only empirical.
The Logic of Quantum Mechanics

One of the aspects of quantum theory which has attracted the most general attention, is the novelty of the logical notions which it presupposes. It asserts that even a complete mathematical description of a physical system S does not in general enable one to predict with certainty the result of an experiment on S, and that in particular one can never predict with certainty both the position and the momentum of S, (Heisenberg’s Uncertainty Principle). It further asserts that most pairs of observations are incompatible, and cannot be made on S, simultaneously (Principle of Non-commutativity of Observations).
An architecture for scholarly publishing on the World Wide Web

Abstract The explosive growth of the World Wide Web (WWW) is due in part to the ease with which information can be made available to Web users. The simplicity of HTML and HTTP servers lowers the barriers to network publishing. The high-quality rendering of HTML in WWW browsers such as Mosaic raises the aesthetic appeal of information and makes it more useful by virtue of enhanced readability. But the simplicity that makes WWW technology so appealing also makes it difficult to represent the complex markup and typography necessary for scholarly publishing. The need for extensive character sets and more effective interface facilities for inter- and intra-document navigation stretch the limits of the current standards that underlie the Web and its clients. In addition, the stateless nature of WWW client-server interactions presents certain challenges to the effective implementation of search and retrieval functionality so important to effective document retrieval systems. OCLC distributes several scholarly journals under its Electronic Journals Online program, acting, in effect, as an “electronic printer” for scholarly publishers. As part of this effort, OCLC is prototyping a WWW-accessible version of these journals. This presentation will describe the problems encountered, detail some of the short-term solutions, and highlight changes to existing standards that will enhance the use of the Web for scholarly electronic publishing.
Experimental measurement of structural power flow on an aircraft fuselage

An experimental technique is used to measure structural intensity through an aircraft fuselage with an excitation load applied near one of the wing attachment locations. The fuselage is a relatively large structure, requiring a large number of measurement locations to analyze the whole of the structure. For the measurement of structural intensity, multiple point measurements are necessary at every location of interest. A tradeoff is therefore required between the number of measurement transducers, the mounting of these transducers, and the accuracy of the measurements. Using four transducers mounted on a bakelite platform, structural intensity vectors are measured at locations distributed throughout the fuselage. To minimize the errors associated with using the four transducer technique, the measurement locations are selected to be away from bulkheads and stiffeners. Furthermore, to eliminate phase errors between the four transducer measurements, two sets of data are collected for each position, with the orientation of the platform with the four transducers rotated by 180 degrees and an average taken between the two sets of data. The results of these measurements together with a discussion of the suitability of the approach for measuring structural intensity on a real structure are presented.
Boundary integral methods for the Poisson equation of continuum dielectric solvation models

This article tests a dielectric model for the variation of hydration free energy with the geometry of complex solutes in water. It reexpresses the Poisson equation of the model to examine the basic aspects of boundary integral methods for these problems. It compares eight examples of dielectric model potentials of mean force in water with numerical results obtained from molecular scale models by simulation. Instructive and physical results are obtained but the model overstabilizes attractive, ion-pairing configurations. The article describes the algorithms, alternative to those in the literature, used here for high-precision solutions of that Poisson equation. Anticipating multigrid boundary integral approaches for similarly accurate treatment of larger solution complexes, the adaptation of spatial resolution is discussed. Finally, the statistical mechanical theory of the model is discussed together with a new proposal for describing the molecular detail of the solvation properties: integrating-out a probe solvent molecule using the dielectric model. The appendices give formal results relevant to periodic boundary conditions and infinite area surfaces such as solution interfaces and membranes. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 64: 121–141, 1997