cssi/SciSciGPT-SciSciNet huggingface dataset:
Seesaws and Social Security Benefits Indexing

The price indexation of Social Security benefit payments has emerged in recent years as a flashpoint of debate in the United States. I characterize the direct effects that changes in that price index would have on retirees who differ in their initial wealth at retirement and in their mortality rates after retirement. I propose a simple but flexible theoretical framework that converts benefits reform first into changes to retirees’ consumption paths and then into a net effect on social welfare. I calibrate that framework using recently produced data on Social Security beneficiaries by lifetime income decile and both existing and new survey evidence on the normative priorities Americans have regarding their Social Security benefits. The results suggest that the value retirees place on protection against longevity risk is an important caveat to the widespread enthusiasm for a switch to a slower-growing price index such as the chained CPI-U.
Fluorescent Nanorods and Nanospheres for Real‐Time In Vivo Probing of Nanoparticle Shape‐Dependent Tumor Penetration

Nanomedicine has offered new hope for cancer treatment.[1] Nanotherapeutics exhibit many advantages over small-molecule chemotherapeutics, including diminished systemic toxicity and improved circulation times. Unfortunately, non-uniformly leaky vasculature[2] and a dense interstitial structure[3] hinder their effective delivery to tumors.[4] These physiological abnormalities make transvascular transport—movement from vessels to the interstitium—and interstitial transport—movement through the interstitium to target cells—heterogeneous.[4a] Hence the tumor microenvironment limits the uniform penetration of nanotherapeutics by slowing or halting their transport through hydrodynamic and steric hindrance.[2a,3a,5] Overcoming these physiological barriers in tumors is an outstanding challenge for nanomedicine.
A model for the critical voltage for electrical degradation of GaN high electron mobility transistors

Abstract It has recently been postulated that GaN high electron mobility transistors under high voltage stress degrade as a result of defect formation induced by excessive mechanical stress that is introduced through the inverse piezoelectric effect. This mechanism is characterized by a critical voltage beyond which irreversible degradation takes place. In order to improve the electrical reliability of GaN HEMTs, it is important to understand and model this degradation process. In this paper, we formulate a first-order model for mechanical stress and elastic energy induced by the inverse piezoelectric effect in GaN HEMTs which allows the computation of the critical voltage for degradation in these devices.
Drop Ejection from an Oscillating Rod

The dynamics of a drop of a Newtonian liquid that is pendant from or sessile on a solid rod that is forced to undergo time-periodic oscillations along its axis is studied theoretically. The free boundary problem governing the time evolution of the shape of the drop and the flow field inside it is solved by a method of lines using a finite element algorithm incorporating an adaptive mesh. When the forcing amplitude is small, the drop approaches a limit cycle at large times and undergoes steady oscillations thereafter. However, drop breakup is the consequence if the forcing amplitude exceeds a critical value. Over a wide range of amplitudes above this critical value, drop ejection from the rod occurs during the second oscillation period from the commencement of rod motion. Remarkably, the shape of the interface at breakup and the volume of the primary drop formed are insensitive to changes in forcing amplitude. The interface shape at times close to and at breakup is a multi-valued function of distance measured along the rod axis and hence cannot be described by recently popularized one-dimensional approximations. The computations show that drop ejection occurs without the formation of a long neck. Therefore, this method of drop formation holds promise of preventing formation of undesirable satellite droplets.
Injective resolutions of BG and derived moduli spaces of local systems

It was suggested on several occasions by Deligne, Drinfeld and Kontsevich that all the moduli spaces arising in the classical problems of deformation theory should be extended to natural \derived" moduli spaces which are always smooth in an appropriate sense and whose tangent spaces involve the entire cohomology of the sheaf of innitesimal automorphisms, not just H 1 . In this note we give an algebraic construction of such an extension for the simplest class of moduli spaces, namely for moduli of local systems (representations of the fundamental group). c 2001 Elsevier Science B.V. All rights reserved. MSC: Primary 18G50; secondary 14D22 Let X be a nite connected CW-complex, x0 2 X be a point, and G be an ane algebraic group over C .A G-local system on X is just a locally constant sheaf of G-torsors. Let LSG(X;x0) denote the set of isomorphism classes of G-local systems trivialized over x0. For such a local system E let [E] denote the corresponding point of LSG(X;x0). This set is naturally an algebraic variety; it is just the variety of all homomorphisms 1(X;x0)!G. It is acted upon by G, and the quotient LSG(X)=LSG(X;x0)=G is the set of isomorphism classes of local systems. Since the G-action may not be free, LSG(X) may not exist as an algebraic variety, but is well dened as an algebraic stack. The rst-order deformation theory gives an identication T[E]LSG(X)=H 1 (X;ad(E)) for any local system. The stack LSG(X) and the variety LSG(X;x0) may be not smooth: the jumping of the dimension of the tangent space is made possible by the corresponding jumping of the dimensions of the higher cohomology of ad(E).
Source localization with distributed sensor arrays and partial spatial coherence

Multiple sensor arrays provide the means for highly accurate localization of the (x,y) position of a source. In some applications, such as microphone arrays receiving aeroacoustic signals from ground vehicles, random fluctuations in the air lead to frequency-selective coherence losses in the signals that arrive at widely separated sensors. We present performance analysis for localization of a wideband source using multiple, distributed sensor arrays. The wavefronts are modeled with perfect spatial coherence over individual arrays and frequency-selective coherence between distinct arrays, and the sensor signals are modeled as wideband, Gaussian random processes. Analysis of the Cramer-Rao bound (CRB) on source localization accuracy reveals that a distributed processing scheme involving bearing estimation at the individual arrays and time-delay estimation (TDE) between sensors on different arrays performs nearly as well as the optimum scheme while requiring less communication bandwidth with a central processing node. We develop Ziv-Zakai bounds for TDE with partially coherent signals in order to study the achievability of the CRB. This analysis shows that a threshold value of coherence is required in order to achieve accurate time-delay estimates, and the threshold coherence value depends on the source signal bandwidth, the additive noise level, and the observation time. Results are included based on processing measured aeroacoustic data from ground vehicles to illustrate the frequency-dependent signal coherence and the TDE performance.
Foreign Aid, Illegal Immigration, and Host Country Welfare

This paper analyzes the effect of foreign aid on illegal immigration and host country welfare using a general equilibrium model. It shows that foreign aid may worsen the recipient nation's terms of trade. Furthermore, it may also raise illegal immigration, if the terms of trade effect on immigration flows dominates the other effects identified in our analysis. Empirical analysis of the effect of foreign aid on illegal immigration to the USA broadly supports the predictions of our theoretical model. Foreign aid worsens the recipient's terms of trade. While the terms of trade effect tends to reduce illegal immigration, countervailing effects are found to dominate. The paper contributes to the related literature by establishing that there are unintended consequences of foreign aid and, while some of them are reminiscent of the classical transfer problem, others are new and arise as a result of endogenous illegal immigration flows.
Bias–Variance and Breadth–Depth Tradeoffs in Respondent-Driven Sampling

Respondent-driven sampling (RDS) is a link-tracing network sampling strategy for collecting data from hard-to-reach populations, such as injection drug users or individuals at high risk of being infected with HIV. The mechanism is to find initial participants (seeds), and give each of them a fixed number of coupons allowing them to recruit people they know from the population of interest, with a mutual financial incentive. The new participants are again given coupons and the process repeats. Currently, the standard RDS estimator used in practice is known as the Volz–Heckathorn (VH) estimator. It relies on strong assumptions about the underlying social network and the RDS process. Via simulation, we study the relative performance of the plain mean and VH estimators when assumptions of the latter are not satisfied, under different network types (including homophily and rich-get-richer networks), participant referral patterns, and varying number of coupons. The analysis demonstrates that the plain mean outpe...
Effect of Water Concentration on the Properties of Commercial Soda‐Lime‐Silica Glasses

The effect of water concentration on the properties of three commercial soda-lime-silica glasses has been measured. Water (H2O) concentration varied from 50 to 550 ppm-wt. Properties measured include glass transformation temperature, transformation range viscosity, thermal expansion coefficient, electrical conductivity, and refractive index. The viscosity, Tg, and electrical conductivity decreased with increasing water content, while the thermal expansion coefficient and refractive index were unaffected by changes in water concentration.
SUSCEPTIBILITY AND VERTEX CORRECTIONS FOR A SQUARE FERMI SURFACE

We investigate the response of an electron system which exhibits ideal nesting features. Using the standard Matsubara formalism we derive analytic expressions for the imaginary and real parts of the bare particle–hole susceptibility. The imaginary part has sharp peaks whose maxima at the nesting momenta approximately scale with (ω/T). The peak lineshapes resemble neutron scattering data on chromium and some copper oxide superconductors. The real part of the bare susceptibility at the nesting vectors diverges logarithmically at low temperatures. Analytic formulas for the first vertex correction to the susceptibility are derived for a Hubbard interaction and its momentum and temperature variations are calculated numerically. This term detracts substantially from the ordinary RPA terms for intermediate values of the Coulomb repulsion. Exact cancellation of a certain class of diagrams at half filling is shown to result from particle–hole symmetry. We discuss the consequences of these results for spin fluctuation theories of high temperature superconductors and spin density wave instabilities.
Total Synthesis of (±)-Aspidospermidine

(±)-Aspidospermidine (1) has been synthesized from readily available methyl 3-ethyl-2-oxocylopentanecarboxylate (17) in 5.9% yield over 13 steps. The key step of the synthesis is an intramolecular cascade reaction that simultaneously forms the B, C, and D rings of 1. A high-yielding method of closing the remaining E ring is also described.
On the complexity of the robust stability problem for linear parameter varying systems

Abstract In this paper, it is shown that the problem of checking robust stability of linear parameter varying (LPV) systems is NP -hard, and therefore, it is rather unlikely to find polynomial-time solution procedures for this problem. In the frequency-domain structured uncertainty case, it is known that the robust stability problem is NP -hard (Toker and Ozbay, 1995; Toker, 1995; Poljak and Rohn, 1993; Nemirovski, 1993; Braatz et al ., 1994), but allowing the uncertain blocks to be time varying gives a computationally tractable problem (Shamma, 1994; Poolla and Tikku, 1995), which can be solved by convex optimization techniques. In the parameteric uncertainty case, NP -hardness of the robust stability problem has been shown in (Poljak and Rohn, 1993; Nemirovski, 1993). The results of this paper show that, allowing the uncertain parameters to be time varying, does not give a computationally simpler problem i.e. it remains NP -hard, and hence it is rather unlikely to find computationally tractable solution procedures for this problem. On the other hand, as far as the existence of an algorithm is considered, there is still no known (non-polynomial time) algorithm for the robust stability problem of linear parameter varying systems (Lagarias and Wang, 1995), and the well-known Tarski's theorem (Tarski, 1951) does not provide a solution procedure (Kozyakin, 1990). Recently, there has been some developments in the direction of constructing non-polynomial-time algorithms for a related problem, called the joint spectral radius (JSR) computation problem (Lagarias and Wang, 1995). We also comment on the use of these results for developing a non-polynomial-time algorithm for testing robust stability of linear parameter varying systems.
Second-Order Stochastic Input-Output Stability and Instability of Interconnected Systems

New results for the second-order stochastic input-output stability and instability of large classes of continuous time and discrete time interconnected stochastic systems are established. The analysis is accomplished in terms of lower order subsystems and in terms of system interconnecting structure. When appropriate, frequency domain interpretations are emphasized. The method of analysis advanced herein is applied to three specific examples. Es werden neue Ergebnisse zur stochastischen Eingabe-Ausgabe-Stabilitat zweiter Ordnung sowie zur Instabilitat von grosen Klassen gekoppelter stochastischer Systeme mit stetiger und diskreter Zeit hergeleitet. Bei der Analyse wird von Teilsystemen niederer Ordnung und von der Koppelstruktur des Systems ausgegangen. Wo das am Platze ist, werden Frequenzbereich-Interpretationen angegeben. Die hier gegebene Untersuchungsmethode wird auf drei konkrete Beispiele angewendet.
Coalition games with cooperative transmission: a cure for the curse of boundary nodes in selfish packet-forwarding wireless networks

In wireless packet-forwarding networks with selfish nodes, application of a repeated game can induce the nodes to forward each others' packets, so that the network performance can be improved. However, the nodes on the boundary of such networks cannot benefit from this strategy, as the other nodes do not depend on them. This problem is sometimes known as the curse of the boundary nodes. To overcome this problem, an approach based on coalition games is proposed, in which the boundary nodes can use cooperative transmission to help the backbone nodes in the middle of the network. In return, the backbone nodes are willing to forward the boundary nodes' packets. Here, the concept of core is used to study the stability of the coalitions in such games. Then three types of fairness are investigated, namely, min-max fairness using nucleolus, average fairness using the Shapley function, and a newly proposed market fairness. Based on the specific problem addressed in this paper, market fairness is a new fairness concept involving fairness between multiple backbone nodes and multiple boundary nodes. Finally, a protocol is designed using both repeated games and coalition games. Simulation results show how boundary nodes and backbone nodes form coalitions according to different fairness criteria. The proposed protocol can improve the network connectivity by about 50%, compared with pure repeated game schemes.
Efficiency of global adaptive quadrature

Techniques for improving the performance of global adaptive quadrature on parallel processors are summarized. Examples using a modification of QUADPACK’s QAG routine are provided.
Squeezing in Floer theory and refined Hofer-Zehnder capacities of sets near symplectic submanifolds

We use Floer homology to study the Hofer–Zehnder capacity of neighborhoods near a closed symplectic submanifold M of a geometrically bounded and symplectically aspherical ambient manifold. We prove that, when the unit normal bundle of M is homologically trivial in degree dim(M) (for example, if codim(M) > dim(M)), a refined version of the Hofer–Zehnder capacity is finite for all open sets close enough to M. We compute this capacity for certain tubular neighborhoods of M by using a squeezing argument in which the algebraic framework of Floer theory is used to detect nontrivial periodic orbits [18, 19, 26]. As an application, we partially recover some existence results of Arnold [1] for Hamiltonian flows which describe a charged particle moving in a nondegenerate magnetic field on a torus. Following [43], we also relate our refined capacity to the study of Hamiltonian paths with minimal Hofer length. AMS Classification numbers Primary: 53D40 Secondary: 37J45
Through-Shell Alkyllithium Additions and Borane Reductions

The through-shell borane reduction and methyllithium addition to benzaldehyde (1), benzocyclobutenone (2), and benzocyclobutenedione (3) incarcerated inside a hemicarcerand (4) with four tetramethylenedioxy bridges are reported. All guests could be reduced and methylated. Selective monoreduction and monomethylation were observed for 3. In the methyllithium addition to 4⊙3, the initially formed lithium alcoholate underwent a Moore rearrangement. The reactivity of the incarcerated guests toward methyllithium increased in the order 1 < 2 ≪ 3 and toward borane in the order 1 ≪ 2 ≈ 3. Guest reactivity was correlated with the inner-phase location of the reacting carbonyl group in the preferred guest inner-phase orientation. The latter was determined from the X-ray structures of 4⊙1, 4⊙2, and 4⊙3, from molecular mechanical calculations, and from the hemicarcerand-induced upfield shift of the guest proton resonances. In the methyllithium and n-butyllithium addition to 4⊙1 and 4⊙3 at elevated temperatures, selecti...
The Hole in the Doughnut: Accounting for Acquired Intangibles at Krispy Kreme

Krispy Kreme Doughnuts, Inc. used a 2000 initial public offering (IPO) to embark on an active expansion and franchise reacquisition program. This case focuses on this high‐visibility franchise reacquisition program and several associated and highly controversial accounting issues, and provides an opportunity to examine numerous technical and conceptual issues in a real‐world setting. In the case, you will encounter a variety of financial reporting issues—from identification and valuation of uncommon intangible assets in Part 1, to acquisition accounting, purchase‐price allocations, contingent consideration, exit costs, executive compensation, and loan impairments in Part 2. The case is appropriate for use in intermediate and advanced accounting courses.
Critical values for multiple structural change tests

Bai and Perron (1998), henceforth BP, considered estimating multiple structural changes in a linear model. The results are obtained under a general framework of partial structural changes which allows a subset of the parameters not to change.1 Methods to efficiently compute estimates are discussed in Bai and Perron (2003). BP also addressed the problem of testing for multiple structural changes under very general conditions on the data and the errors: they considered a type test for the null hypothesis of no change vs. a pre-specified number of changes and also vs. an alternative of an arbitrary number of changes (up to some maximum), as well as a procedure that allows one to test the null hypothesis of, say, I changes, vs. the alternative hypothesis of I + 1 changes. The latter is particularly useful in that it allows a specific to general modeling strategy to consistently determine the appropriate number of changes in the data. The tests can be constructed allowing different serial correlation in the errors, different distribution for the data and the errors across segments or imposing a common structure.
Party Nationalization and Institutions

Party nationalization has two distinct components: the first is based on the degree of homogeneity in the geographic distribution of a party's vote, and the other is defined by the degree to which national events are reflected in the change in a party's electoral support in all regions of the country. In spite of literature tying the static/distributional and the dynamic components together, we show theoretically and empirically that there is a nonnecessary link between them. We then use a seemingly unrelated regression analysis on 60 parties across 28 countries to show that while the executive system (presidentialism vs. parliamentarism) drives an explanation of the dynamic levels of nationalization, the electoral system explains much of the variance in the static/distributional aspect of the phenomenon.
Noise-induced sampling of alternative Hamiltonian paths in quantum adiabatic search

We numerically simulate the effects of noise-induced sampling of alternative Hamiltonian paths on the ability of quantum adiabatic search (QuAdS) to solve randomly generated instances of the NP-complete problem N-bit Exact Cover 3. The noise-averaged median runtime is determined as the noise-power and number of bits N are varied, and power-law and exponential fits are made to the data. Noise is seen to slowdown QuAdS, though a downward shift in the scaling exponent is found for N > 12 over a range of noise-power values. We discuss whether this shift might be connected to arguments in the literature that suggest that altering the Hamiltonian path might benefit QuAdS performance. © 2008 Wiley Periodicals, Inc. Complexity, 2009 This article was submitted as an invited paper to the “Understanding Complex Systems” conference held at the University of Illinois at Urbana-Champaign,May 2007
Hsp90 and Environmental Stress Transform the Adaptive Value of Natural Genetic Variation

How can species remain unaltered for long periods yet also undergo rapid diversification? By linking genetic variation to phenotypic variation via environmental stress, the Hsp90 protein-folding reservoir might promote both stasis and change. However, the nature and adaptive value of Hsp90-contingent traits remain uncertain. In ecologically and genetically diverse yeasts, we find such traits to be both common and frequently adaptive. Most are based on preexisting variation, with causative polymorphisms occurring in coding and regulatory sequences alike. A common temperature stress alters phenotypes similarly. Both selective inhibition of Hsp90 and temperature stress increase correlations between genotype and phenotype. This system broadly determines the adaptive value of standing genetic variation and, in so doing, has influenced the evolution of current genomes.
Improving Vision-Based Self-Positioning in Intelligent Transportation Systems via Integrated Lane and Vehicle Detection

Traffic congestion is a widespread problem. Dynamic traffic routing systems and congestion pricing are getting importance in recent research. Lane prediction and vehicle density estimation is an important component of such systems. We introduce a novel problem of vehicle self positioning which involves predicting the number of lanes on the road and vehicle's position in those lanes using videos captured by a dashboard camera. We propose an integrated closed-loop approach where we use the presence of vehicles to aid the task of self-positioning and vice versa. To incorporate multiple factors and high-level semantic knowledge into the solution, we formulate this problem as a Bayesian framework. In the framework, the number of lanes, the vehicle's position in those lanes and the presence of other vehicles are considered as parameters. We also propose a bounding box selection scheme to reduce the number of false detections and increase the computational efficiency. We show that the number of box proposals decreases by a factor of 6 using the selection approach. It also results in large reduction in the number of false detections. The entire approach is tested on real-world videos and is found to give acceptable results.
Synthesis of novel 1,3,4‐oxadiazinane‐2‐thiones derived from (1R,2S‐ephedrine, (1S,2S)‐pseudoephedrine and (1R,2S)‐norephedrine

A several novel 1,3,4-oxadiazinan-2-thiones have been synthesized by the cyclization of β-hydrazino-alcohols with either carbon disulfide or 1,1′-thiocarbonyldiimidazole (TCDI).
Theory of confined states of positronium in spherical and circular quantum dots with Kane’s dispersion law

Confined states of a positronium (Ps) in the spherical and circular quantum dots (QDs) are theoretically investigated in two size quantization regimes: strong and weak. Two-band approximation of Kane’s dispersion law and parabolic dispersion law of charge carriers are considered. It is shown that electron-positron pair instability is a consequence of dimensionality reduction, not of the size quantization. The binding energies for the Ps in circular and spherical QDs are calculated. The Ps formation dependence on the QD radius is studied.
Changes in optic disk characteristics and the number of nerve fibers in experimental glaucoma

We compared the change in cup/disk ratio and neuroretinal rim area-to-disk area to estimated change in the number of optic nerve fibers in 12 cynomolgus monkeys with unilateral experimental glaucoma. Changes in the cup/disk ratios and neuroretinal rim area-to-disk area were estimated from stereoscopic optic disk photographs that were obtained before and after the development of increased intraocular pressure. Change in the number of optic nerve fibers in the glaucomatous nerves was estimated by comparing them to their fellow normal nerves. A significant linear correlation was present between change in the cup/disk ratios and neuroretinal rim area-to-disk area, and estimated change in the number of optic nerve fibers (r > or = .85; P < .0002). In optic disks with initial cup/disk ratios of 0.2 to 0.3 and neuroretinal rim area-to-disk area of 0.9, an increase in the cup/disk ratio of 0.1 and a decrease of 0.1 in the neuroretinal rim area-to-disk area is associated with a 10% and 9% loss of optic nerve fibers, respectively.
Libcint: An efficient general integral library for Gaussian basis functions.

An efficient integral library Libcint was designed to automatically implement general integrals for Gaussian-type scalar and spinor basis functions. The library is able to evaluate arbitrary integral expressions on top of p, r and σ operators with one-electron overlap and nuclear attraction, two-electron Coulomb and Gaunt operators for segmented contracted and/or generated contracted basis in Cartesian, spherical or spinor form. Using a symbolic algebra tool, new integrals are derived and translated to C code programmatically. The generated integrals can be used in various types of molecular properties. To demonstrate the capability of the integral library, we computed the analytical gradients and NMR shielding constants at both nonrelativistic and 4-component relativistic Hartree–Fock level in this work. Due to the use of kinetically balanced basis and gauge including atomic orbitals, the relativistic analytical gradients and shielding constants requires the integral library to handle the fifth-order electron repulsion integral derivatives. The generality of the integral library is achieved without losing efficiency. On the modern multi-CPU platform, Libcint can easily reach the overall throughput being many times of the I/O bandwidth. On a 20-core node, we are able to achieve an average output 8.3 GB/s for C60 molecule with cc-pVTZ basis. © 2015 Wiley Periodicals, Inc.
Language, logic and ontology: Uncovering the structure of commonsense knowledge

The purpose of this paper is twofold: (i) we argue that the structure of commonsense knowledge must be discovered, rather than invented; and (ii) we argue that natural language, which is the best known theory of our (shared) commonsense knowledge, should itself be used as a guide to discovering the structure of commonsense knowledge. In addition to suggesting a systematic method to the discovery of the structure of commonsense knowledge, the method we propose seems to also provide an explanation for a number of phenomena in natural language, such as metaphor, intensionality, and the semantics of nominal compounds. Admittedly, our ultimate goal is quite ambitious, and it is no less than the systematic 'discovery' of a well-typed ontology of commonsense knowledge, and the subsequent formulation of the long-awaited goal of a meaning algebra.
Asymmetric phase-transfer catalyzed glycolate alkylation, investigation of the scope, and application to the synthesis of (-)-ragaglitazar.

Asymmetric glycolate alkylation using a protected acetophenone surrogate under solid−liquid phase-transfer conditions is a new approach to the synthesis of 2-hydroxy esters and acids. Diphenylmethyloxy-2,5-dimethoxyacetophenone 1 with a trifluorobenzyl cinchonidinium bromide catalyst 9 (10 mol %) and cesium hydroxide provided S-alkylation products 2 at −35 °C in high yield (80−99%) and with excellent enantioselectivities using a wide range of electrophiles (80−90% ee). Alkylated products were elaborated to useful α-hydroxy intermediates 3 using bis-TMS peroxide Baeyer−Villiger conditions and selective transesterification reactions. The ester products have been enantioenriched by simple recrystallization from ether to give a single isomer (99% ee). A tight ion-pair model is proposed for the observed S-stereoinduction that includes van der Waals contacts between the extended enolate and the isoquinoline of the catalyst. To demonstrate the utility of the new methodology, the anti-diabetes drug (−)-ragaglitaz...
Straight homogeneous generalized cylinders: analysis of reflectance properties and a necessary condition for class membership

Consideration is given to two membership tests for straight homogeneous generalized cylinders to determine if an object in the image is a member of the shape class. It is shown that contour information alone is insufficient to recover a straight homogeneous generalized cylinder uniquely. It is then shown that the sign and magnitude of the Gaussian curvature at a point vary among members of a contour-equivalent class. Next, a method of ruling straight homogeneous generalized cylinder images is developed. This ruling of the surface serves two functions. First, the ruling algorithm provides a heuristic test of whether or not the image is consistent with that of a straight homogeneous generalized cylinder. Secondly, the ruling makes explicit certain parameters of the underlying straight homogeneous generalized cylinder that the authors use in their second membership test. The second membership test is an intensity-based method which assumes that the surface has geodesics and that the albedo is constant. The method compares intensity values at corresponding meridian points along cross-sectional geodesics. >
Effect of Estrogen on Molecular and Functional Characteristics of the Rodent Vaginal Muscularis

Abstract Introduction. Vaginal atrophy is a consequence of menopause; however, little is known concerning the effect of a decrease in systemic estrogen on vaginal smooth muscle structure and function. As the incidence of pelvic floor disorders increases with age, it is important to determine if estrogen regulates the molecular composition and contractility of the vaginal muscularis. Aim The goal of this study was to determine the effect of estrogen on molecular and functional characteristics of the vaginal muscularis utilizing a rodent model of surgical menopause. Methods Three‐ to 4‐month old Sprague‐Dawley rats underwent sham laparotomy (Sham, N = 18) or ovariectomy (Ovx, N = 39). Two weeks following surgery, animals received a subcutaneous osmotic pump containing vehicle (Sham, Ovx) or 17β‐estradiol (Ovx). Animals were euthanized 1 week later, and the proximal vagina was collected for analysis of contractile protein expression and in vitro studies of contractility. Measurements were analyzed using a one‐way analysis of variance followed by Tukey's post hoc analysis (α = 0.05). Main Outcome Measures Protein and mRNA transcript expression levels of contractile proteins, in vitro measurements of vaginal contractility. Results Ovariectomy decreased the expression of carboxyl‐terminal myosin heavy chain isoform (SM1) and h ‐caldesmon and reduced the amplitude of contraction of the vaginal muscularis in response to KCl. Estradiol replacement reversed these changes. No differences were detected in the % vaginal muscularis, mRNA transcript expression of amino‐terminal MHC isoforms, l ‐caldesmon expression, and maximal velocity of shortening. Conclusion Systemic estrogen replacement restores functional and molecular characteristics of the vaginal muscularis of ovariectomized rats. Our results indicate that menopause is associated with changes in the vaginal muscularis, which may contribute to the increased incidence of pelvic floor disorders with age.
Dual-Joint Modeling for Estimation of Total Knee Replacement Contact Forces During Locomotion

Model-based estimation of in vivo contact forces arising between components of a total knee replacement is challenging because such forces depend upon accurate modeling of muscles, tendons, ligaments, contact, and multibody dynamics. Here we describe an approach to solving this problem with results that are tested by comparison to knee loads measured in vivo for a single subject and made available through the Grand Challenge Competition to Predict in vivo Tibiofemoral Loads. The approach makes use of a "dual-joint" paradigm in which the knee joint is alternately represented by (1) a ball-joint knee for inverse dynamic computation of required muscle controls and (2) a 12 degree-of-freedom (DOF) knee with elastic foundation contact at the tibiofemoral and patellofemoral articulations for forward dynamic integration. Measured external forces and kinematics were applied as a feedback controller and static optimization attempted to track measured knee flexion angles and electromyographic (EMG) activity. The resulting simulations showed excellent tracking of knee flexion (average RMS error of 2.53 deg) and EMG (muscle activations within ±10% envelopes of normalized measured EMG signals). Simulated tibiofemoral contact forces agreed qualitatively with measured contact forces, but their RMS errors were approximately 25% of the peak measured values. These results demonstrate the potential of a dual-joint modeling approach to predict joint contact forces from kinesiological data measured in the motion laboratory. It is anticipated that errors in the estimation of contact force will be reduced as more accurate subject-specific models of muscles and other soft tissues are developed.
Commission Splits in Real Estate Transactions

We examine commission splits between listing and selling agents in real estate transactions. We construct a theoretical model to show that agency problems arise when a listing agent attempts to maximize his or her payoff while setting the commission split. Mitigation to these agency problems can be achieved through the imposition of a limited duration on listing contracts. Our model produces several testable hypotheses, which are supported by empirical evidence. We find property listings with higher list prices and quick sales are associated with lower commission splits. Commission split is more likely to be higher when the listed property has a high degree of atypicality and/or is overpriced. Additionally, agent-owned properties pay higher commission splits.
A generalized processor sharing approach to flow control in integrated services networks: the multiple node case

Worst-case bounds on delay and backlog are derived for leaky bucket constrained sessions in arbitrary topology networks of generalized processor sharing (GPS) servers. The inherent flexibility of the service discipline is exploited to analyze broad classes of networks. When only a subset of the sessions are leaky bucket constrained, we give succinct per-session bounds that are independent of the behavior of the other sessions and also of the network topology. However, these bounds are only shown to hold for each session that is guaranteed a backlog clearing rate that exceeds the token arrival rate of its leaky bucket. A much broader class of networks, called consistent relative session treatment (CRST) networks is analyzed for the case in which all of the sessions are leaky bucket constrained. First, an algorithm is presented that characterizes the internal traffic in terms of average rate and burstiness, and it is shown that all CRST networks are stable. Next, a method is presented that yields bounds on session delay and backlog given this internal traffic characterization. The links of a route are treated collectively, yielding tighter bounds than those that result from adding the worst-case delays (backlogs) at each of the links in the route. The bounds on delay and backlog for each session are efficiently computed from a universal service curve, and it is shown that these bounds are achieved by "staggered" greedy regimes when an independent sessions relaxation holds. Propagation delay is also incorporated into the model. Finally, the analysis of arbitrary topology GPS networks is related to Packet GPS networks (PGPS). The PGPS scheme was first proposed by Demers, Shenker and Keshav (1991) under the name of weighted fair queueing. For small packet sizes, the behavior of the two schemes is seen to be virtually identical, and the effectiveness of PGPS in guaranteeing worst-case session delay is demonstrated under certain assignments. >
Software Architectures for E-Commerce Computing Systems with External Hosting

Several medium to large companies are currently in the process of using external hosting to deploy their internet applications. External hosting by such application service providers (ASPs) as IBM provides a secure and reliable way for companies to deploy e-commerce enterprise applications without the need to purchase costly infrastructure. However, when software is designed for applications that run on the servers of external hosts, the performance may suffer if the data and the application reside at two different locations. The authors provide a technique for improving the performance in such applications. This technique is implemented in large software systems that the authors are associated with as industry consultants. The software architecture and preliminary performance results are provided.
Novel sesquiterpenes and a lactone from the Jamaican sponge Myrmekioderma styx

Abstract Two novel sesquiterpenes, styxone A ( 1 ) and styxone B ( 2 ), and a novel lactone, styxlactone ( 3 ), were isolated from the Jamaican sponge Myrmekioderma styx . Their structures were elucidated by detailed 1 H, 13 C and 2D NMR data and the absolute stereochemistry of styxone A and B was determined by CD spectra. Styxone A represents a novel sesquiterpene skeleton. ( S )-(+)-Curcuphenol ( 4 ), ( S )-(+)-curcudiol ( 5 ), and abolene ( 6 ) were also isolated. An activity enhancement by cyanthiwigin B ( 7 ) to curcuphenol was observed in the antimicrobial assays when the two compounds were administered together.
On bounded languages and reversal-bounded automata

Bounded context-free languages have been investigated for nearly fifty years, yet they continue to generate interest as seen from recent studies. Here, we present a number of results about bounded context-free languages. First we give a new (simpler) proof that every context-free language L ? w 1 * w 2 * ? w n * can be accepted by a PDA with at most 2 n - 3 reversals. We also introduce new collections of bounded context-free languages and present some of their interesting properties. Some of the properties are counter-intuitive and may point to some deeper facts about bounded CFLs. We present some results about semilinear sets and also present a generalization of the well-known result that over a one-letter alphabet, the families of context-free and regular languages coincide.
Studies of a Channel through Padre Island, Texas

Construction of 125 ft wide 12 ft deep navigation canal through Padre Island and Laguna Madre to Port Mansfield; results of investigations on effects of disturbance of natural equilibrium on Gulf shore by construction of jetties and channel; requirements for design and reconstruction of suitable jettied navigation channel through inlet; problems of tidal hydraulics encountered in design of artificial inlet.
An optimal decay estimate for the linearized water wave equation in 2D

We obtain a decay estimate for solutions to the linear dispersive equation $iu_t-(-\Delta)^{1/4}u=0$ for $(t,x)\in\mathbb{R}\times\mathbb{R}$. This corresponds to a factorization of the linearized water wave equation $u_{tt}+(-\Delta)^{1/2}u=0$. In particular, by making use of the Littlewood-Paley decomposition and stationary phase estimates, we obtain decay of order $|t|^{-1/2}$ for solutions corresponding to data $u(0)=\varphi$, assuming only bounds on $\lVert \varphi\rVert_{H_x^1(\mathbb{R})}$ and $\lVert x\partial_x\varphi\rVert_{L_x^2(\mathbb{R})}$. As another application of these ideas, we give an extension to equations of the form $iu_t-(-\Delta)^{\alpha/2}u=0$ for a wider range of $\alpha$.
Compensated Neutron Log Response Issues

Compensated neutron (CN) logs have been around for many years, and have been used successfully for many petrophysical applications. Although the basic design and general response characteristics of these instruments have remained relatively constant over the years, service companies have refined the response characterizations and have updated their hardware, providing evolutionary improvements. Unfortunately, the general understanding among petrophysicists of how CN instruments work and how best to make use of the log data appears to have lagged or perhaps even worsened in recent years. This paper discusses several obstacles to understanding and interpreting neutron logs and proposes some techniques for avoiding problems. Although this paper is not an exhaustive treatment of CN logging issues, some of the more important ones are discussed. Some alternative ways of looking at the data are presented.
Vitamin D as Supplemental Therapy for Pneumocystis Pneumonia

The combination of all-trans retinoic acid (ATRA) and primaquine (PMQ) has been shown to be effective for therapy of Pneumocystis pneumonia (PCP). Since a high concentration of ATRA has significant adverse effects, the possibility that vitamin D can be used to replace ATRA for PCP therapy was investigated. C57BL/6 mice were immunosuppressed by depleting CD4(+) cells and infected with Pneumocystis murina 1 week after initiation of immunosuppression. Three weeks after infection, the mice were treated orally for 3 weeks with vitamin D3 (VitD3) alone, PMQ alone, a combination of VitD3 and PMQ (VitD3-PMQ), or a combination of trimethoprim and sulfamethoxazole (TMP-SMX). Results showed that VitD3 (300 IU/kg/day) had a synergistic effect with PMQ (5 mg/kg/day) for therapy of PCP. Flow cytometric studies showed that this VitD3-PMQ combination recovered the CD11b(low) CD11c(high) alveolar macrophage population in mice with PCP as effectively as TMP-SMX. The VitD3-PMQ combination also reduced the massive infiltration of inflammatory cells into the lungs and the severity of lung damage. VitD3 was also shown to reduce the dose of TMP-SMX required for effective treatment of PCP. Taken together, results of this study suggest that a VitD3-PMQ combination can be used as an alternative therapy for PCP.
Towards a realistic parsing of the Feynman path integral

The Feynman path integral does not allow a one real path interpretation, because the quantum amplitudes contribute to probabilities in a non-separable manner. The opposite extreme, all paths happen , is not a useful or informative account. In this paper it is shown that an intermediate parsing of the path integral, into realistic non-interfering possibilities, is always available. Each realistic possibility formally corresponds to numerous particle paths, but is arguably best interpreted as a spacetime-valued field. Notably, one actual field history can always be said to occur, although it will generally not have an extremized action. The most obvious concerns with this approach are addressed, indicating necessary follow-up research. But without obvious showstoppers, it seems plausible that the path integral might be reinterpreted to explain quantum phenomena in terms of Lorentz covariant field histories. Quanta 2016; 5: 1–11.
Parallelizing the QUDA Library for Multi-GPU Calculations in Lattice Quantum Chromodynamics

Graphics Processing Units (GPUs) are having a transformational effect on numerical lattice quantum chromo- dynamics (LQCD) calculations of importance in nuclear and particle physics. The QUDA library provides a package of mixed precision sparse matrix linear solvers for LQCD applications, supporting single GPUs based on NVIDIA's Compute Unified Device Architecture (CUDA). This library, interfaced to the QDP++/Chroma framework for LQCD calculations, is currently in production use on the "9g" cluster at the Jefferson Laboratory, enabling unprecedented price/performance for a range of problems in LQCD. Nevertheless, memory constraints on current GPU devices limit the problem sizes that can be tackled. In this contribution we describe the parallelization of the QUDA library onto multiple GPUs using MPI, including strategies for the overlapping of communication and computation. We report on both weak and strong scaling for up to 32 GPUs interconnected by InfiniBand, on which we sustain in excess of 4 Tflops.
Properties and Management of Soils in the Tropics

The long-awaited second edition of this classic textbook expands on the first edition to include advances made in the last four decades, bringing the topic completely up to date. The book addresses critical issues such as whether humanity can feed itself, and whether it can do so in environmentally sound and sustainable ways. Written from agronomic, environmental, and ecological standpoints, the textbook employs a multidisciplinary approach, including policymaking and plant genetic improvements, as well as ecosystem services, climate change, biodiversity, sustainability and resilience. New chapters in this second edition focus on organic carbon in soil, soil biology, soils in relation to livestock production and forestry, and agroforestry. The new edition will again be the go-to textbook for courses on tropical soils, and a reference textbook for soil and agricultural scientists and development professionals working in the tropics.
Elastic Properties and Network Structure in Silicone Gum Vulcanizates

Abstract A model of a rubber network formed from finite, linear polymer chains is treated, using expressions from accepted elastic theory as well as relations that have been less generally used or only implied. The resultant empirical mathematical expressions conform very closely to the predictions of the simple kinetic theory of rubber elasticity and are mathematically consistent, in that the major properties and measurements are interrelated, and apparent inconsistencies in the literature are reconciled. As a consequence, an empirical equation is developed for the relationship between elastic properties and network structure in silicone gum vulcanizates. This equation is then applied to the estimation of peroxide crosslinking efficiencies.
Alcohol and catecholamine disposition:: A role for tetrahydroisoquinoline alkaloids

Abstract The current work was undertaken to explore the possibility that TIQs may play a role during alcohol intoxication and/or in post-intoxication states. At the present time, the available data show only that the catecholamine-derived TIQs are interesting pharmacologic agents for manipulating aspects of catecholaminergic function; Much remains to be done to explore the potential actions of the TIQs and to delineate their role(s) in the bodily responses to alcohol.