cssi/SciSciGPT-SciSciNet huggingface dataset:
An iterative algorithm for fitting nonconvex penalized generalized linear models with grouped predictors

High-dimensional data pose challenges in statistical learning and modeling. Sometimes the predictors can be naturally grouped where pursuing the between-group sparsity is desired. Collinearity may occur in real-world high-dimensional applications where the popular l"1 technique suffers from both selection inconsistency and prediction inaccuracy. Moreover, the problems of interest often go beyond Gaussian models. To meet these challenges, nonconvex penalized generalized linear models with grouped predictors are investigated and a simple-to-implement algorithm is proposed for computation. A rigorous theoretical result guarantees its convergence and provides tight preliminary scaling. This framework allows for grouped predictors and nonconvex penalties, including the discrete l"0 and the 'l"0+l"2' type penalties. Penalty design and parameter tuning for nonconvex penalties are examined. Applications of super-resolution spectrum estimation in signal processing and cancer classification with joint gene selection in bioinformatics show the performance improvement by nonconvex penalized estimation.
Palladium-catalyzed aerobic oxidative C-H olefination with removable 1,2,3-triazole directing group.

Ortho-olefination of arenes was achieved with removable 1,2,3-triazole auxiliary through Pd-catalyzed C–H activation. Excellent yields were received even when molecular O2 (1 atm) was used as the terminal oxidant. Other heterocyclic directing groups, such as pyridine and quinoline, gave poor reactivity under this aerobic oxidative condition, which highlighted the unique reactivity of triazole in promoting directed C–H activation.
Containment of Conjunctive Queries on Annotated Relations

We study containment and equivalence of (unions of) conjunctive queries on relations annotated with elements of a commutative semiring. Such relations and the semantics of positive relational queries on them were introduced in a recent paper as a generalization of set semantics, bag semantics, incomplete databases, and databases annotated with various kinds of provenance information. We obtain positive decidability results and complexity characterizations for databases with lineage, why-provenance, and provenance polynomial annotations, for both conjunctive queries and unions of conjunctive queries. At least one of these results is surprising given that provenance polynomial annotations seem “more expressive” than bag semantics and under the latter, containment of unions of conjunctive queries is known to be undecidable. The decision procedures rely on interesting variations on the notion of containment mappings. We also show that for any positive semiring (a very large class) and conjunctive queries without self-joins, equivalence is the same as isomorphism.
THOMAS: building Bayesian statistical expert systems to aid in clinical decision making

Knowledge-based system for classical statistical analysis must separate the task of analyzing data from that of using the results of the analysis. In contrast, a Bayesian framework for building biostatistical expert system allows for the integration of the data-analytic and decision-making tasks. The architecture of such a framework entails enabling the system (1) to make its recommendations on decision-analytic grounds; (2) to construct statistical models dynamically; (3) to update a statistical model based on the user's prior beliefs and on data from, the methodological concerns evinced by, the study. This architecture permits the knowledge engineer to represent a variety of types of statistical and domain knowledge. Construction of such systems requires that the knowledge engineer reinterpret traditional statistical concerns, such as by replacing the notion of statistical significance with that of a pragmatic clinical threshold. The clinical user of such a system can interact with the system at a semantic level appropriate to her fund of methodological knowledge, rather than at the level of statistical details. We demonstrate these issues with a prototype system called THOMAS which helps a physician decision maker interpret the results of a published randomized clinical trial.
First-Order Performance Prediction Techniques For Charge-Coupled Device Scanning Imagers

Modulation transfer function (MTF) and pseudo-MTF analytical techniques are applied to the problem of predicting system performance for reconnaissance sensors that incorporate charge-coupled device (CCD) imaging detectors. The MTF analyses, used in conjunction with assumptions about signal-to-noise (S/N) requirements and a simplified weather model, provide a much-needed systems design tool.
A FAR-ULTRAVIOLET STUDY OF THE HOT WHITE DWARF IN THE DWARF NOVA WW CETI

We present a synthetic spectral analysis of IUE archival and FUSE (Far Ultraviolet Spectroscopic Explorer) far-UV spectra of the peculiar dwarf nova WW Cet. During the quiescence of WW Cet, a white dwarf with Twd ~ 26,000 ? 1000 K can account for the far-UV flux and yields the proper distance. However, the best agreement with the observations is provided by a two-temperature white dwarf model with a cooler white dwarf at Twd = 25,000 K providing 75% of the far-UV flux and a hotter region (accretion belt or optically thick disk ring) with T = 40,000 K contributing 25% of the flux for the proper distance. We find from the FUSE spectrum that the white dwarf is rotating with V sin i = 600 ? 100 km s-1. Our temperature results provide an additional data point in the distribution of WD Twd versus orbital period above the CV period gap, where few WD Twd values are available.
Simulations of the Fuel Economy and Emissions of Hybrid Transit Buses over Planned Local Routes

We present simulated fuel economy and emissions city transit buses powered by conventional diesel engines and diesel-hybrid electric powertrains of varying size. Six representative city drive cycles were included in the study. In addition, we included previously published aftertreatment device models for control of CO, HC, NOx, and particulate matter (PM) emissions. Our results reveal that bus hybridization can significantly enhance fuel economy by reducing engine idling time, reducing demands for accessory loads, exploiting regenerative braking, and shifting engine operation to speeds and loads with higher fuel efficiency. Increased hybridization also tends to monotonically reduce engine-out emissions, but trends in the tailpipe (post-aftertreatment) emissions involve more complex interactions that significantly depend on motor size and drive cycle details.
Break-Induced Replication Is a Source of Mutation Clusters Underlying Kataegis

Clusters of simultaneous multiple mutations can be a source of rapid change during carcinogenesis and evolution. Such mutation clusters have been recently shown to originate from DNA damage within long single-stranded DNA (ssDNA) formed at resected double-strand breaks and dysfunctional replication forks. Here, we identify double-strand break (DSB)-induced replication (BIR) as another powerful source of mutation clusters that formed in nearly half of wild-type yeast cells undergoing BIR in the presence of alkylating damage. Clustered mutations were primarily formed along the track of DNA synthesis and were frequently associated with additional breakage and rearrangements. Moreover, the base specificity, strand coordination, and strand bias of the mutation spectrum were consistent with mutations arising from damage in persistent ssDNA stretches within unconventional replication intermediates. Altogether, these features closely resemble kataegic events in cancers, suggesting that replication intermediates during BIR may be the most prominent source of mutation clusters across species.
New Insights in the Pathogenesis of Multiple Sclerosis—Role of Acrolein in Neuronal and Myelin Damage

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) characterized by an inappropriate inflammatory reaction resulting in widespread myelin injury along white matter tracts. Neurological impairment as a result of the disease can be attributed to immune-mediated injury to myelin, axons and mitochondria, but the molecular mechanisms underlying the neuropathy remain incompletely understood. Incomplete mechanistic knowledge hinders the development of therapies capable of alleviating symptoms and slowing disease progression in the long-term. Recently, oxidative stress has been implicated as a key component of neural tissue damage prompting investigation of reactive oxygen species (ROS) scavengers as a potential therapeutic option. Despite the establishment of oxidative stress as a crucial process in MS development and progression, ROS scavengers have had limited success in animal studies which has prompted pursuit of an alternative target capable of curtailing oxidative stress. Acrolein, a toxic β-unsaturated aldehyde capable of initiating and perpetuating oxidative stress, has been suggested as a viable point of intervention to guide the development of new treatments. Sequestering acrolein using an FDA-approved compound, hydralazine, offers neuroprotection resulting in dampened symptom severity and slowed disease progression in experimental autoimmune encephalomyelitis (EAE) mice. These results provide promise for therapeutic development, indicating the possible utility of neutralizing acrolein to preserve and improve neurological function in MS patients.
All-order quantum gravity in two dimensions

Abstract We derive curvature counterterms in two-dimensional gravity coupled to conformal matter up to infinite order. By construction the higher-order action is equivalent to a finite first-order theory with an auxiliary scalar. Due to this equivalence it shares the following remarkable properties: There is no need for gravitational dressing of the cosmological constant, quantization is consistent for any conformal anomaly c of the coupled matter system, and if the coupled matter system is a ( c = d )-dimensional string theory in a euclidean background then the effective string theory is ( D = d + 2)-dimensional with Minkowski signature (1, D −1). The resulting quantum theory favours flat geometries and suppresses both parabolic and hyperbolic singularities.
How Protective Is Protective Clothing

A standard method to evaluate the permeation resistance of protective clothing has been developed. This method has generated numerous data on the resistance of various clothing materials to specific chemicals. Three chemicals for which little data were available are formaldehyde, chlorine, and hydrogen cyanide. Experience with the method in evaluating materials for their resistance to these chemicals is presented as well as a review of current methods for determining protective clothing performance. Results from the tests show that nitrile-butadiene, neoprene, and butyl rubber offer the best resistance to formaldehyde, chlorine, and hydrogen cyanide, respectively, and that both breakthrough time and permeation rate data are needed to determine performance.
Non-linear actuation response of polyvinylidene fluoride (PVDF) based nanocomposites

Recent research on overcoming inherent limitations on the electromechanical properties of polyvinylidene fluoride (PVDF) and copolymers has been directed towards adding nanoinclusions to take advantage of their scale and properties. This research shows that adding single walled carbon nanotubes (SWNTs) creates a quadratic electromechanical response in PVDF. Enhanced effective dielectric constant and formation of polar microstructure suggests an electrostrictive response. Contributions from Joule heating will be assessed next, as they may be significant at higher SWNT content.
Optical properties of ALON (aluminum oxynitride)

The optical properties of ALON (aluminum oxynitride) are presented. Optical scatter and index of refraction, and absorption of several different compositions of ALON are compared. The temperature dependence of emissivity of ALON was measured in the temperature range 46°C to 1200°C.
Nickel and Palladium Catalysis in the Stereoselective Synthesis of Functionalized Pyrrolidines: Enantioselective Formal Synthesis of (+)-α-Allokainic Acid.

Neuroexcitatory natural products are accessible from 1 via the intermediate 2, which is obtained by Ni-catalyzed cyclization, transposition of the protecting group, and Pd-catalyzed reduction with allylic transposition. This stepwise formation of stereocenters allows a highly direct and stereoselective synthesis of the excitatory amino acid (+)-α-allokainic acid, which displays an all-trans arrangement of the substituents about the pyrrolidine ring. TBS=tert-butyldimethylsilyl.
Mode Selective Coaxial Directional Couplers for Harmonic Measurements

Bethe's small-hole coupling theory is applied to coaxial transmission line to design mode selective directional couplers. By independently sampling the TEM and TE11 modes in coaxial line, harmonic measurements can be performed which would require five or more directional couplers if made in rectangular waveguide. Mode selectivity on the order of 30 dB has been achieved.
X-ray constraints on the shape of the dark matter in five Abell clusters

X-ray observations obtained with the Einstein Observatory are used to constrain the shape of the dark matter in the inner regions of Abell clusters A401, A426, A1656, A2029, and A2199, each of which exhibits highly flattened optical isopleths. The dark matter is modeled as an ellipsoid with a mass density of about r exp -2. The possible shapes of the dark matter is constrained by comparing these model isophotes to the image isophotes. The X-ray isophotes, and therefore the gravitational potentials, have ellipticities of about 0.1-0.2. The dark matter within the central 1 Mpc is found to be substantially rounder for all the clusters. It is concluded that the shape of the galaxy distributions in these clusters traces neither the gravitational potential nor the gravitating matter.
RECENT ADVANCES IN THE STUDY OF MESOPOROUS METAL-ORGANIC FRAMEWORKS

Metal–organic frameworks (MOFs), which consist of metal ions or clusters and organic bridging ligands, have recently emerged as an important family of porous materials. In this comment, we discuss the current state of the field pertaining to MOFs with pore sizes between 2 and 50 nm, which have great application potential in gas storage, separation, sensor, catalysis, and drug delivery. This review will cover mesoporous MOFs containing 3-D channels, 1-D channels, and large cavities, as well as those based on supramolecular templates.
Net campaign contributions, agricultural interests, and votes on liberalizing trade with China

We consider the potential influence of contributions from interest groups to political rivals in the voting behavior of US legislators on international trade policy issues. Our application addresses the determinants of the Permanent Normal Trade Relations with China decision, and focuses particular attention on the agriculture/agribusiness lobby. A simultaneous voting-net contributions model suggests that these contributions were very effective relative to organized labor and other corporate groups, despite their relatively small dollar value. Possible explanations arising from differences in targeting strategies are explored.
Constant rank bimatrix games are PPAD-hard

The rank of a bimatrix game (A, B) is defined as rank(A + B). Computing a Nash equilibrium (NE) of a rank-0, i.e., zero-sum game is equivalent to linear programming (von Neumann'28, Dantzig'51). In 2005, Kannan and Theobald gave an FPTAS for constant rank games, and asked if there exists a polynomial time algorithm to compute an exact NE. Adsul et. al. (2011) answered this question affirmatively for rank-1 games, leaving rank-2 and beyond unresolved. In this paper we show that NE computation in games with rank ≥ 3, is PPAD-hard, settling a decade long open problem. Interestingly, this is the first instance that a problem with an FPTAS turns out to be PPAD-hard. Our reduction bypasses graphical games and game gadgets, and provides a simpler proof of PPAD-hardness for NE computation in bimatrix games. In addition, we get: • An equivalence between 2D-Linear-FIXP and PPAD, improving a result by Etessami and Yannakakis (2007) on equivalence between Linear-FIXP and PPAD. • NE computation in a bimatrix game with convex set of Nash equilibria is as hard as solving a simple stochastic game [12]. • Computing a symmetric NE of a symmetric bimatrix game with rank ≥ 6 is PPAD-hard. • Computing a 1/poly(n)-approximate fixed-point of a (Linear-FIXP) piecewise-linear function is PPAD-hard. The status of rank-2 games remains unresolved.
Steering control of singularly perturbed systems: a composite control approach

Abstract This paper presents a composite control approach to the problem of steering the state of a singularly perturbed system from a given initial state to a given final state, while minimizing a cost functional. The problem is treated for a class of nonlinear systems whose fast dynamics are weakly nonlinear in the fast variables and control inputs. The composite control comprises three components: a reduced control, a feedback boundary-layer stabilizing control and an open-loop right boundary-layer control. It is shown that application of the composite control results in a final state that is O(ϵ) close to the desired state, and a value of the cost that is O(ϵ) close to the optimal cost of the reduced problem.
Laser-assisted microscale deformation of stainless steels and ceramics

This work investigates deformation of stainless steel and ceramic specimens with a precision on the order of submicrometers by use of a pulsed laser beam as the energy source. Such a technique is useful, for example, in a process of removing distortions on magnetic head components for a better contact between the magnetic disk head and the hard disk surface. Experiments are conducted to study the bending behavior of stainless steel and ceramics due to laser irradiation. A pulsed Nd:YLF laser beam is used to scan over the specimen to create out-of-plane deformation. The amount of deformation from each laser scan is correlated with various laser and processing parameters. A theoretical model of the laser deformation process is presented based on thermo-elasticity/plasticity. The laser deformation process is explained as a result of the laser-induced non-uniform distribution of the residual strain. Numerical simulations are carried out to estimate the laser-induced temperature field, the residual stress field, and the amount of deformation of the specimen. These theoretical studies help to understand the complex phenomena involved in the pulsed laser deformation process.
Molecular hydrogen and oxygen interactions with armchair Si nanotubes

Molecular hydrogen and oxygen adsorptions on a (6, 6) armchair silicon nanotube have been studied by optimizing the distances of the admolecules from both inside and outside the tube. Full geometry and spin optimizations have been performed without any symmetry constraints with an all electron 3-21G* basis set and the B3LYP functional. The molecule is originally placed perpendicular or parallel to the tube axis. Hydrogen adsorption with the molecular axis aligned parallel to the surface of the nanotube is less favorable. Hydrogen molecule does not dissociate while oxygen molecule dissociates after optimization. The on-top site is the only preferred site for hydrogen molecule with an adsorption energy of 3.71 eV and an optimized distance of 3.31 for external adsorption whereas the on-top site is the most preferred site with adsorption energy of 3.69 eV for internal adsorption. For oxygen, the molecule dissociates and the most preferred sites are the two bridge sites with an adsorption energy of 9.64 eV, the optimized distance being 1.65/1.68 A when it is adsorbed from the outside of the tube. When oxygen molecule is originally placed at on-top site it will hold as a molecule after adsorption with a slightly increased bond length. For the internal adsorption of oxygen, the molecules also dissociate in most cases and the zigzag bridge site is the most preferred site. After molecular adsorption for both hydrogen and oxygen, the buckling of the nanotubes increased. Frustration effects in the nanotube due to molecular adsorption are also noted.
Total synthesis of (+/-)-actinophyllic acid.

The first total synthesis of (±)-actinophyllic acid (1) is reported. Key steps of this synthesis include an intramolecular oxidative coupling of ketone and malonic ester enolates and an aza-Cope−Mannich rearrangement that assembled the core structure of the natural product’s unique ring system. The synthesis was accomplished from di-tert-butyl malonate in 8% overall yield by a concise sequence that proceeds by way of only seven isolated intermediates.
Resonance broadening induced nonlinear saturation of kinetic Alfvén turbulence in the interplanetary plasma

Abstract The saturation of ion-cyclotron Alfven turbulence excited by beam particles is investigated using the resonance broadening theory. The stochastic scattering which decorrelates particles, includes both random acceleration by electric fields and a turbulent magnetic mirroring effect. Turbulent mirroring is shown to yield non-Gaussian corrections to the orbits even if the random electric and magnetic fields are Gaussian. The predicted steady-state turbulence level exhibits a peaked angular distribution, with a maximum near Θ ⋍ 60° .
EFFECTS OF MAGNETIC FIELD STRENGTH AND ORIENTATION ON MOLECULAR CLOUD FORMATION

We present a set of numerical simulations addressing the effects of magnetic field strength and orientation on the flow-driven formation of molecular clouds. Fields perpendicular to the flows sweeping up the cloud can efficiently prevent the formation of massive clouds but permit the buildup of cold, diffuse filaments. Fields aligned with the flows lead to substantial clouds, whose degree of fragmentation and turbulence strongly depends on the background field strength. Adding a random field component leads to a selection effect for molecular cloud formation: high column densities are only reached at locations where the field component perpendicular to the flows is vanishing. Searching for signatures of colliding flows should focus on the diffuse, warm gas, since the cold gas phase making up the cloud will have lost the information about the original flow direction because the magnetic fields redistribute the kinetic energy of the inflows.
Revisiting the Zintl-Klemm concept: alkali metal trielides.

To enhance understanding of the Zintl–Klemm concept, which is useful for characterizing chemical bonding in semimetallic and semiconducting valence compounds, and to more effectively rationalize the structures of Zintl phases, we present a partitioning scheme of the total energy calculated on numerous possible structures of the alkali metal trielides, LiAl, LiTl, NaTl, and KTl, using first-principles quantum mechanical calculations. This assessment of the total energy considers the relative effects of covalent, ionic, and metallic interactions, all of which are important to understand the complete structural behavior of Zintl phases. In particular, valence electron transfer and anisotropic covalent interactions, explicitly employed by the Zintl–Klemm concept, are often in competition with isotropic, volume-dependent metallic and ionic interaction terms. Furthermore, factors including relativistic effects, electronegativity differences, and atomic size ratios between the alkali metal and triel atoms can af...
Selective primary health care: an interim strategy for disease control in developing countries.

Abstract Priorities among the infectious diseases affecting the three billion people in the less developed world have been based on prevalence, morbidity, mortality and feasibility of control. With these priorities in mind a program of selective primary health care is compared with other approaches and suggested as the most cost-effective form of medical intervention in the least developed countries. A flexible program delivered by either fixed or mobile units might include measles and diptheria-pertussis-tetanus vaccination, treatment for febrile malaria and oral rehydration for diarrhea in children, and tetanus toxoid and encouragement of breast feeding in mothers. Other interventions might be added on the basis of regional needs and new developments. For major diseases for which control measures are inadequate, research is an inexpensive approach on the basis of cost per infected person per year.
Regioselectivity in the Lithiation of O-(4-Methoxyphenyl)-N,N-diethylthiocarbamate: Relative Directed Metalation Abilities of Methoxy and N,N-diethylthiocarbamate Functionalities

Abstract Directed ortho metalation is a useful approach to the regioselective synthesis of polysubstituted aromatics.1 The regioselectivity of the metalation can depend, in some instances, on the relative positions and directing abilities of two or more functional groups, and studies to establish the relative directing abilities of ortho metalation groups have been reported.1 The O-aryl carbamates are particularly powerful ortho-metalation directors and have been employed effectively in the construction of a variety of polysubstituted aromatic compounds.1,2
Choice of Evils: In Search of a Viable Rationale

The defense of necessity, also known as the “choice of evils,” reflects popular moral intuitions and common sense: sometimes, breaking the rules is the right—indeed, the only—thing to do in order to avoid a greater evil. Citing a classic example, mountain climbers may break into a cabin to wait out a deadly snow storm and appropriate the owner’s provisions because their property violations are a lesser evil compared to the loss of life. At the same time, this defense contradicts the fundamental principles of criminal responsibility in that it authorizes violation of rights of innocent bystanders. By allowing the mountain climbers to override the property rights of the cabin owner, the defense effectively forbids the cabin owner to use force in response—a different rule would perpetuate violence. This outcome is at odds with the basic criminal law doctrines. There is no general duty to rescue in Anglo-American law. Yet, by forbidding the cabin owner to use force, the defense of necessity essentially imposes on him the duty to forego his interests in favor of those of the mountain climbers. The paper explores the origins and boundaries of the defense of necessity. It argues that the existing public and private theories of necessity are unsatisfactory and concludes that a viable theory of necessity should be able to explain why it is sometimes permissible to override individual rights of citizens without their consent or fault.
The Plight of Mixed Race Adolescents

Over the past 40 years, the fraction of mixed race black-white births has increased nearly nine-fold. There is very little empirical evidence on how these children fare relative to their single-race counterparts. This paper describes basic facts about the behaviors and outcomes of black-white mixed race individuals. As one might expect, on a host of background and achievement characteristics as well as adult outcomes, mixed race individuals fall in between whites and blacks. When it comes to engaging in risky and anti-social adolescent behavior, however, mixed race adolescents are stark outliers compared to both blacks and whites. We argue that these behavioral patterns are most consistent with a two-sector Roy model, in which mixed race adolescents – not having a predetermined peer group – engage in more risky behaviors to be accepted.
A refined higher-order composite box beam theory

Abstract A three-dimensional theory is developed to model composite box beams with arbitrary wall thicknesses. The theory, which is based on a refined displacement field, approximates the three-dimensional elasticity solution so that the beam cross-sectional properties are not reduced to one-dimensional beam parameters. Both in-plane and out-of-plane warping are included automatically in the formulation. The model can accurately capture the transverse shear stresses through the thickness of each wall while satisfying stress-free boundary conditions on the inner and outer surfaces of the beam. Numerical results are presented for beams with varying wall thicknesses and aspect ratios. The static results are correlated with available experimental data and show excellent agreement. Results presented for thick-walled box beams show the importance of including transverse shear in the formulation and the difficulty of defining a ‘beam’ twist for the entire cross-section.
Measuring charge trap occupation and energy level in CdSe/ZnS quantum dots using a scanning tunneling microscope

We use a scanning tunneling microscope to probe single-electron charging phenomena in individual CdSe/ZnS (core/shell) quantum dots (QDs) at room temperature. The QDs are deposited on top of a bare Au thin film and form a double-barrier tunnel junction (DBTJ) between the tip, QD, and substrate. Analysis of room-temperature hysteresis in the current-voltage $(IV)$ tunneling spectra, is consistent with trapped charge(s) presenting an additional potential barrier to tunneling, a measure of the Coulomb blockade. The paper describes the first direct electrical measurement of the trap-state energy on individual QDs. Manipulation of the charge occupation of the QD, verified by measuring the charging energy, $(61.4\ifmmode\pm\else\textpm\fi{}2.4)\text{ }\text{meV}$, and analysis of the DBTJ, show trap states $\ensuremath{\sim}1.09\text{ }\text{eV}$ below the QD conduction-band edge. In addition, the detrapping time, a measure of the tunneling barrier thickness, is determined to have an upper time limit of 250 ms. We hypothesize that the charge is trapped in a quantum-dot surface state.
Building an Online Data Management Plan Tool

Following the 2011 announcement by the National Science Foundation (NSF) that it would begin requiring Data Management Plans with every funding application, the University of Houston Libraries explored ways to support our campus researchers in meeting this requirement. A small team of librarians built an online tool using a Drupal module. The tool includes informational content, an interactive questionnaire, and an extensive FAQ to meet diverse researcher needs. This easily accessible and locally maintained tool allows us to provide a high level of personalized service to our researchers.
A simple framework for nonparametric specification testing

This paper presents a simple framework for testing the specification of parametric conditional means. The test statistics are based on quadratic forms in the residuals of the null model. Under general assumptions the test statistics are asymptotically normal under the null. With an appropriate choice of the weight matrix, the tests are shown to be consistent and to have good local power. Specific implementations involving matrices of bin and kernel weights are discussed. Finite sample properties are explored in simulations.
Ketone-Based Transition-Metal-Catalyzed Carbon–Carbon and Carbon–Hydrogen Bond Activation: Exploratory Studies

The importance and ubiquity of ketone functional groups in organic synthesis has always been a driving force for discovering new modes of reactivity. Stimulated by the challenges of fused-ring synthesis and ketone alkylation, we summarize here our exploratory studies on ketone-based transition-metal-catalyzed carbon–carbon and carbon–hydrogen bond activation.
The loop-erased random walk and the uniform spanning tree on the four-dimensional discrete torus

Let x and y be points chosen uniformly at random from \({\mathbb {Z}_n^4}\), the four-dimensional discrete torus with side length n. We show that the length of the loop-erased random walk from x to y is of order n2(log n)1/6, resolving a conjecture of Benjamini and Kozma. We also show that the scaling limit of the uniform spanning tree on \({\mathbb {Z}_n^4}\) is the Brownian continuum random tree of Aldous. Our proofs use the techniques developed by Peres and Revelle, who studied the scaling limits of the uniform spanning tree on a large class of finite graphs that includes the d-dimensional discrete torus for d ≥ 5, in combination with results of Lawler concerning intersections of four-dimensional random walks.
Highly Enantioselective Michael Reactions Catalyzed by a Chiral Quaternary Ammonium Salt. Illustration by Asymmetric Syntheses of (S)-Ornithine and Chiral 2-Cyclohexenones

The use of the chiral quaternary ammonium salts 1a and 1b makes possible enantioselective Michael reactions which have been applied to the asymmetric syntheses of (S)-ornithine (2) and the chiral 2-cyclohexenone 6.
The crystal structure of the influenza matrix protein M1 at neutral pH: M1-M1 protein interfaces can rotate in the oligomeric structures of M1.

The influenza matrix protein (M1) forms a protein layer under the viral membrane and is essential for viral stability and integrity. M1 mediates the encapsidation of the viral RNPs into the viral membrane by its membrane and RNP-binding activities. In order to understand the roles of M1-M1 protein interactions in forming the M1 layer, X-ray crystallographic studies of a M1 fragment (1-162) were carried out at neutral pH and compared with an acidic pH structure. At neutral pH the asymmetric unit was a stacked dimer of M1. A long molecular ribbon of neutral stacked dimers was formed by translation as dictated by the P1 space group. The elongated ribbon had a positively charged stripe on one side of the ribbon. A similar M1-M1 stacking interface was also found in the acidic asymmetric unit. However, within the acidic stacked dimer the molecules were not straight, but rotated in relation to each other by slightly changing the M1-M1 stacking interface. The acidic structure possessed an additional M1-M1 twofold interface. Protein docking confirmed that the M1-M1 stacking and M1-M1 twofold interfaces could be used to form a double ribbon of M1 molecules. By iterative repetition of the rotated relationship among the M1 molecules, a helix of M1 was generated. These studies suggest that M1 has the ability to form straight or bent elongated ribbons and helices. These oligomers are consistent with previous electron microscopic studies of M1, which demonstrated that isolated M1 formed elongated and flexible ribbons when isolated from what appeared to be a helical shell of M1 in the influenza virus.
Quarkonium decays and light quark masses

Abstract The SU(3)-violating decays π 2 S → π 1 S X , where X = π 0 or η and π= J ψ ϒ have been recently proposed as a means of probing the light quark masses beyond leading order in chiral perturbation theory. We argue that this analysis is incorrect, even in the heavy quark limit. We show that these decays are governed by an infinite number of matrix elements which are not suppressed by any small parameter, and which cannot be computed with our present understanding of QCD. Furthermore, for sufficiently heavy quarks, we show that the decay amplitudes can be organized into a twist expansion, and that the contributions considered in the above proposal are subleading in this expansion. We also explain how these decays nonetheless give a constraint on the light quark masses valid at leading order in the chiral expansion. The decays π 1 S → ηγ and π 2 S → π 1 ππ also have contributions from infinitely many operators, contrary to claims in the literature.
A new look at the isotropy of narrow-line emission in extragalactic radio sources

We undertake a quantitative investigation, using Monte Carlo simulations, of the amount by which quasars are expected to exceed radio galaxies in optical luminosity in the context of the ‘receding torus’ model. We compare these simulations with the known behaviour of the [O III] λ5007 and [O II] λ3727 emission lines and conclude that [O III] is the better indicator of the strength of the underlying non-stellar continuum.
The impact of patient cost-sharing on low-income populations: Evidence from Massachusetts ☆

Greater patient cost-sharing could help reduce the fiscal pressures associated with insurance expansion by reducing the scope for moral hazard. But it is possible that low-income recipients are unable to cut back on utilization wisely and that, as a result, higher cost-sharing will lead to worse health and higher downstream costs through increased use of inpatient and outpatient care. We use exogenous variation in the copayments faced by low-income enrollees in the Massachusetts Commonwealth Care program to study these effects. We estimate separate price elasticities of demand by type of service. Overall, we find price elasticities of about -0.16 for this low-income population - similar to elasticities calculated for higher-income populations in other settings. These elasticities are somewhat smaller for the chronically sick, especially for those with asthma, diabetes, and high cholesterol. These lower elasticities are attributable to lower responsiveness to prices across all categories of service, and to some statistically insignificant increases in inpatient care.
Developing a Compton polarimeter to measure polarization of hard x-rays in the 50-300 keV energy range

This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are particularly interested in X-rays that are emitted from solar flares and gamma-ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead, to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high-Z crystal scintillator. We can monitor individual Compton scatters that occur in the plastics and determine whether the photon is photo absorbed by the high-Z crystal or not. A Compton scattered photon that is immediately photo absorbed by the high-Z crystal constitutes a valid event. These valid events provide us with the interaction locations of each incident photon and ultimately produces a modulation pattern for the Compton scattering of the polarized radiation. Comparing with Monte Carlo simulations of a 100% polarized beam, the level of polarization of the measured beam can then be determined. The complete array is mounted on a flat-panel multi-anode photomultiplier tube (MAPMT) that can measure the deposited energies resulting from the photon interactions. The design of the detector allows for a large field-of-view, at the same time offering the ability to be close-packed with multiple modules in order to reduce deadspace. We plan to present in this paper the latest laboratory results obtained from GRAPE using partially polarized radiation sources.
Laparoscopic Burch Colposuspension Versus Tension-Free Vaginal Tape: A Randomized Trial

Seventy-two women from 2 institutions wererandomized: 36 to laparoscopic Burch colposuspensionand 36 to TVT. Multichannel urodynamic tests were per-formedpreoperativelyand1yearaftersurgery.Aresearchnurse administered the Urogenital Distress Inventory, In-continenceImpactQuestionnaire,andpelvicexaminationsusing the pelvic organ prolapse quantiﬁcation system pre-operatively, and at 6 months, 1 year, and 2 years aftersurgery. Voiding diaries were collected at 1 and 2 years.Primaryoutcomewasobjectivecure,whichwasdeﬁnedasno evidence of urinary leakage during postoperative uro-dynamic studies. Secondary outcomes included subjectivecontinence, perioperative and postoperative data, andquality of life.
The Voice of the Customer

In recent years, many U.S. and Japanese firms have adopted Quality Function Deployment QFD. QFD is a total-quality-management process in which the "voice of the customer" is deployed throughout the R&D, engineering, and manufacturing stages of product development. For example, in the first "house" of QFD, customer needs are linked to design attributes thus encouraging the joint consideration of marketing issues and engineering issues. This paper focuses on the "Voice-of-the-Customer" component of QFD, that is, the tasks of identifying customer needs, structuring customer needs, and providing priorities for customer needs. In the identification stage, we address the questions of 1 how many customers need be interviewed, 2 how many analysts need to read the transcripts, 3 how many customer needs do we miss, and 4 are focus groups or one-on-one interviews superior? In the structuring stage the customer needs are arrayed into a hierarchy of primary, secondary, and tertiary needs. We compare group consensus affinity charts, a technique which accounts for most industry applications, with a technique based on customer-sort data. In the stage which provides priorities we present new data in which product concepts were created by product-development experts such that each concept stressed the fulfillment of one primary customer need. Customer interest in and preference for these concepts are compared to measured and estimated importances. We also address the question of whether frequency of mention can be used as a surrogate for importance. Finally, we examine the stated goal of QFD, customer satisfaction. Our data demonstrate a self-selection bias in satisfaction measures that are used commonly for QFD and for corporate incentive programs. We close with a brief application to illustrate how a product-development team used the voice of the customer to create a successful new product.
Testing methods for determination of fracture toughness of metals

Abstract The determination of the fracture toughness properties of pressure vessel materials is of increasing importance in reducing the risk of low stress fracture. This paper reviews the present status of testing methods and indicates their ranges of application.
The effect of Chinese hepatoprotective medicines on experimental liver injury in mice

The purpose of this study was to compare the hepatoprotective effects of seven Chinese herbal compounds/mixtures on four known hepatotoxicants in mice. These compounds include fulvotomentosides oleanolic acid, total saponins of Panax japonicus (Jgs), total saponins of Panax notoginseng (Ngs), sweroside, oxymatrine, and dimethyl dicarboxylate biphenyl (DDB). All have previously been reported to exhibit hepatoprotective effects. Acute liver injury was produced in male CF-1 mice by CCl4, acetaminophen, cadmium chloride and allyl alcohol. Liver damage was assessed by quantifying serum activities of sorbitol dehydrogenase and alanine aminotransferase, as well as by histopathological examination. Fulvomentosides markedly decreased the toxicity produced by all four hepatotoxicants; oleanic acid also remarkably decreased acetaminophen, CCl4 and Cd-induced hepatotoxicity, but had no effect on allyl alcohol; total saponins of Panax japonicus and Panax notoginseng had moderate hepatoprotective effects on these models except that total saponins of Panax japonicus markedly decreased allyl alcohol toxicity; sweroside decreased Cd and CCl4 toxicity but had no effect on the other two hepatotoxicants; oxymatrine only decreased allyl alcohol toxicity; whereas DDB did not protect against any of the hepatotoxicants. The mechanism(s) by which these compounds/mixtures protect against different types of hepatotoxicants requires further investigation. In conclusion, of the seven compounds examined, fulvotomentoside and oleanolic acid appear to be the most effective in protecting against chemical-induced liver injury.
Nilpotent coadjoint orbits in small characteristic

Abstract We show that the numbers of nilpotent coadjoint orbits in the dual of exceptional Lie algebra G 2 in characteristic 3 and in the dual of exceptional Lie algebra F 4 in characteristic 2 are finite. We determine the closure relation among nilpotent coadjoint orbits in the dual of Lie algebras of type B , C , F 4 in characteristic 2 and in the dual of Lie algebra of type G 2 in characteristic 3. In each case we give an explicit description of the nilpotent pieces in the dual defined in [2] , which are in general unions of nilpotent coadjoint orbits, coincide with the earlier case-by-case definition in [11] , [26] in the case of classical groups and have nice properties independent of the characteristic of the base field. This completes the classification of nilpotent coadjoint orbits in the dual of Lie algebras of reductive algebraic groups and the determination of closure relation among such orbits in all characteristic.
Who's in charge here?—or Alice searches for a king in Mediland

There is no king in Mediland. Despite Alice's yearning—and she speaks for millions who seek simple solutions to complex problems—there probably never will be, as long as we remain a democracy. What is needed is a shared, multi-group, responsibility within a framework of clearly, but democratically, defined public accountability. Five groups share major responsibility, for both our current problems and their solution: consumers, doctors, hospitals, private health-insurance carriers, and the government. Within this shared responsibility, the pre-eminent role will probably go to the group demonstrating greatest capacity for leadership, which, paradoxically, may mean greatest capacity for self-discipline. The extent to which this self-discipline and leadership are realized may determine whether we achieve a creative new synthesis for medical education, health-care delivery and financing, or whether we doom ourselves to a mutually destructive stalemate.
Multiple Access Channels With States Causally Known at Transmitters

It has been recently shown by Lapidoth and Steinberg that strictly causal state information can be beneficial in multiple access channels (MACs). Specifically, it was proved that the capacity region of a two-user MAC with independent states, each known strictly causally to one encoder, can be enlarged by letting the encoders send compressed past state information to the decoder. In this study, a generalization of the said strategy is proposed whereby the encoders compress also the past transmitted codewords along with the past state sequences. The proposed scheme uses a combination of long-message encoding, compression of the past state sequences and codewords without binning, and joint decoding over all transmission blocks. The proposed strategy has been recently shown by Lapidoth and Steinberg to strictly improve upon the original one. Capacity results are then derived for a class of channels that include two-user modulo-additive state-dependent MACs. Moreover, the proposed scheme is extended to state-dependent MACs with an arbitrary number of users. Finally, output feedback is introduced and an example is provided to illustrate the interplay between feedback and availability of strictly causal state information in enlarging the capacity region.
Maintaining the Ranch topology

Topology maintenance, or how to handle the possibly concurrent joining and leaving of nodes, is a central problem for structured peer-to-peer networks. A good topology maintenance protocol should run efficiently, fully maintain the topology, and should not unduly restrict concurrency. In this paper, we present such a protocol for a multi-ring topology called Ranch. The protocol is efficient: for each join or leave, it uses a logarithmic number of messages with high probability. The protocol fully maintains Ranch after joins and leaves, and allows for a high degree of concurrency. To our knowledge, this is the first maintenance protocol that enjoys all of these properties for a structured peer-to-peer network topology.