cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnetic and Ising quantum phase transitions in a model for isoelectronically tuned iron pnictides

Considerations of the observed bad-metal behavior in Fe-based superconductors led to an early proposal for quantum criticality induced by isoelectronic P for As doping in iron arsenides, which has since been experimentally confirmed. We study here an effective model for the isoelectronically tuned pnictides using a large-$N$ approach. The model contains antiferromagnetic and Ising-nematic order parameters appropriate for ${J}_{1}\ensuremath{-}{J}_{2}$ exchange-coupled local moments on an Fe square lattice, and a damping caused by coupling to itinerant electrons. The zero-temperature magnetic and Ising transitions are concurrent and essentially continuous. The order-parameter jumps are very small, and are further reduced by the interplane coupling; consequently, quantum criticality occurs over a wide dynamical range. Our results reconcile recent seemingly contradictory experimental observations concerning the quantum phase transition in the P-doped iron arsenides.
Maximum likelihood function used to calculate confidence of association rules in market baskets

In this paper we are concerned in looking at different ways for calculating the strength of Association Rules in Market Basket data. The significance of Association rules is measured via two measures support and confidence and the way these measures are used to determine strong rules. In the realm of Market Basket Research these measures can be used to find the strength of the rules in a particular transaction of the form, "When a customer buys items A&B also buys item C". The first portion of this paper illustrates the usage of the method of Maximum Likelihood for Point Estimation and gives an idea how the maximum likelihood estimator can also be used for predicting the confidence of an association rule. The second portion of the paper mainly describes with examples how maximum likelihood function can be used for calculating the collective confidence of association rules.
Seawater sampling by an autonomous underwater vehicle: “Gulper” sample validation for nitrate, chlorophyll, phytoplankton, and primary production

The effort and expense associated with sample and data collections for long oceanographic time series are, in part, driving the development of autonomous platforms, sensors and sample collectors. Here we validate basic oceanographic samples collected by an autonomous underwater vehicle with water sampler (AUV with “Gulper”) by comparison with samples collected by a standard collection device, the conductivity-temperature-depth rosette with Niskin bottles. After elimination of a toxic material, “on-deck” and field comparisons show that Gulpers and Niskin bottles collect comparable nitrate, chlorophyll, phytoplankton species and 14C-based primary production (PP) samples and data. Gulper materials and lubricants, Gulper firing, field presence of the possibly toxic submarine, and the pressure and temperature cycling associated with the submarine's depth undulations all appear unimportant. However, 24 h sample hold periods for live samples within the Gulpers, as is necessary during many AUV deployments, appears to depress nitrate, chlorophyll and PP values somewhat (4–16%). While challenges remain, demonstration that the AUV and sampler can collect fundamental oceanographic samples is a critical step toward the broader use of such autonomous platforms.
No Taxation without Information: Deterrence and Self-Enforcement in the Value Added Tax

Abstract Claims that the VAT facilitates tax enforcement by generating paper trails on transactions between firms contributed to widespread VAT adoption worldwide, but there is surprisingly little evidence. This paper analyzes the role of third-party information for VAT enforcement through two randomized experiments among over 400,000 Chilean firms. Announcing additional monitoring has less impact on transactions that are subject to a paper trail, indicating the paper trail's preventive deterrence effect. This leads to strong enforcement spillovers up the VAT chain. These findings confirm that when taking evasion into account, significant differences emerge between otherwise equivalent forms of taxation. (JEL D83, H25, H26, K34, O17)
A New Error Bound for Shifted Surface Spline Interpolation

Shifted surface spline is a frequently used radial function for scattered data interpolation. The most frequently used error bounds for this radial function are the one raised by Wu and Schaback in [17] and the one raised byMadych and Nelson in [14]. Both are O(dl) as d → 0, where l is a positive integer and d is the well-known fill-distance which roughly speaking measures the spacing of the data points. Then RBF people found that there should be an error bound of the form O(ω 1 d ) because shifted surface spline is smooth and every smooth function shares this property. This only problem was that the value of the cucial constant ω was unknown. Recently Luh raised an exponential-type error bound with convergence rate O(ω 1 d ) as d → 0 where 0 < ω < 1 is a fixed constant which can be accurately computed [11]. Although the exponential-type error bound converges much faster than the algebraic-type error bound, the constant ω is intensely influenced by the dimension n in the sense ω → 1 rapidly as n → ∞. Here the variable x of both the interpolated and interpolating functions lies in Rn. In this paper we present an error bound which is O(√dω′1d ) where 0 < ω′ < 1 is a fixed constant for any fixed n, and is only mildly influenced by n. In other words, ω′ → 1 very slowly as n → ∞, and ω′
Numerical Analysis of Magnetic Field Amplification by Turbulence

We apply a Fourier spectral numerical method to the study of three-dimensional incompressible MHD turbulence with a magnetic Prandtl number Pr ≥ 1. We examine the processes by which an initially weak, large-scale seed magnetic field and an initially weak, small-scale, impulse-like seed magnetic field are amplified. We find that in both cases the magnetic energy spectrum grows at all scales. The growth rates at different amplification stages are analyzed. For a large-scale seed magnetic field, the magnetic energy density grows as ~t2 for the first few turbulence eddy turnover times, followed by a dynamic growth stage, where nonlinear interactions between different scales of the turbulence contribute to an exponential growth rate that is largely determined by the turbulence eddy turnover time. For a seed magnetic field that is initially set up at a small scale in the turbulence, during the kinematic development stage, the growth rate of magnetic energy is ∝1/τmax, where τmax is the eddy turnover time of the smallest eddies of the turbulence. The kinematic growth stage is followed by a dynamic growth stage, where nonlinearity plays important role. During such dynamic growth stage, the growth rate of total magnetic energy is determined by both the magnetic energy amplification within the turbulence inertial range and that within the turbulence dissipation range.
Production probability estimators for context-free grammars

Abstract The problem of production probability estimation is considered. We examine the estimation of production probabilities for context-free probabilistic grammars (CFPGs). Given a context-free grammar, G, and a random sample of strings from L(G), we define ratio estimators to estimate the production probabilities of G. It is shown that the statistical analysis of the estimators becomes much less complex by using the theory of random walks. The main result of the article is that the biases and variances of all ratio estimators for any Chomsky Normal Form CFPG are approximately directly proportional to 1 n , where n is the size of the random sample. Random samples consisting of strings generated from an independent source are used to validate theoretical results. We show that the estimates can be used to increase the efficiency of parsing strings in a language. The ability to parse strings efficiently is extremely useful in compiler theory and the theory of artificial intelligence.
Update on the Pyramid Scheme

We summarize recent work in which we attempt to make consistent models of LHC physics, from the Pyramid Scheme. The models share much with the NMSSM, in particular, enhanced tree level contributions to the Higgs mass and a preference for small tanβ. There are three different singlet fields, and a new strongly coupled gauge theory, so the constraints of perturbative unification are quite different. We outline our general approach to the model, which contains a Kahler potential for three of the low energy fields, which is hard to calculate. Detailed calculations, based on approximations to the Kahler potential, will be presented in a future publication.
Extreme values of zeta and L-functions

We introduce a resonance method to produce large values of the Riemann zeta-function on the critical line, and large and small central values of L-functions.
DPGA Utilization and Application

Dynamically Programmable Gate Arrays (DPGAs) are programmable arrays which allow the strategic reuse of limited resources. In so doing, DPGAs promise greater capacity, and in some cases higher performance, than conventional programmable device architectures where all array resources are dedicated to a single function for an entire operational epoch. This paper examines several usage patterns for DPGAs including temporal pipelining, utility functions, multiple function accommodation, and state-dependent logic. In the process, it offers insight into the application and technology space where DPGA-style reuse techniques are most beneficial.
A model of mass extinction.

Abstract In the last few years a number of authors have suggested that evolution may be a so-called self-organized critical phenomenon, and that critical processes might have a significant effect on the dynamics of ecosystems. In particular it has been suggested that mass extinction may arise through a purely biotic mechanism as the result of “coevolutionary avalanches”. In this paper we first explore the empirical evidence which has been put forward in favor of this conclusion. The data center principally around the existence of power-law functional forms in the distribution of the sizes of extinction events and other quantities. We then propose a new mathematical model of mass extinction which does not rely on coevolutionary effects and in which extinction is caused entirely by the action of environmental stress on species. In combination with a simple model of species adaption we show that this process can account for all the observed data without the need to invoke coevolution and critical processes. The model also makes some independent predictions, such as the existence of “aftershock” extinctions in the aftermath of large mass extinction events, which should in theory be testable against the fossil record.
Zero energy solutions of the Dirac equation in an N-pseudoparticle field☆

Abstract Zero-energy solutions of the Dirac equation are found for a fermion in the field of a Euclidean Yang-Mills pseudoparticle configuration with Pontryagin number N . In this field we find N non-singular normalizable zero-energy solutions.
A Game-Theoretic Model Of The CouP D'État

I explore the comparative vulnerability of regimes to a coup d'etat using a game-theoretic model. Analysis centers on leaders of groups capable of intervening at the time of a coup. I prove the existence of an equilibrium in which a coup is attempted without restrictions on current government policy, the breadth of participation in politics, or the relative size of the conspiracy. Comparative statics results concerning the willingness of plotters to stage a coup and other leaders to join a coup once under way are established. Differences in comparative regime vulnerability stem from differences in the amount of organization required to attempt a coup.
Total synthesis of cochleamycin A.

Cochleamycin A (1) was synthesized in 2.4% overall yield via a 23-step linear sequence starting from 3-butene-1-ol. Key features of the synthesis include the synthesis of (Z)-1,3-diene 21 via a Stille coupling of 4 and 5 and a transannular Diels−Alder reaction of macrocycle 26 to provide the complete carbon skeleton of 1.
An Alternative Medicine Study of Herbal Effects on the Penetration of Zona-Free Hamster Oocytes and the Integrity of Sperm Deoxyribonucleic Acid

Abstract Objective: To analyze the effects of certain herbs on sperm DNA and on the fertilization process. Design: Prospective comparative study. Setting: Clinical and academic research environment. Patient(s): Donor sperm specimens. Intervention(s): Zona-free hamster oocytes were incubated for 1 hour in saw palmetto ( Serenoa repens ), echinacea purpura, ginkgo biloba, St. John's wort ( Hypericum perforatum ), or control medium before sperm-oocyte interaction. The DNA of herb-treated sperm was analyzed with denaturing gradient gel electrophoresis. Main Outcome Measure(s): Oocyte penetration and integrity of the sperm BRCA1 exon 11 gene. Result(s): Pretreatment of oocytes with 0.6 mg/mL of St. John's wort resulted in zero penetration. A lower concentration (0.06 mg/mL) had no effect. High concentrations of echinacea and ginkgo also resulted in reduced oocyte penetration. Exposure of sperm to echinacea purpura and St. John's wort resulted in DNA denaturation. In contrast, saw palmetto and ginkgo had no effect. Sperm exposed to 0.6 mg/mL of St. John's wort showed mutation of the BRCA1 exon 11 gene. Conclusion(s): High concentrations of St. John's wort, echinacea, and ginkgo had adverse effects on oocytes. Saw palmetto had no effect. The data suggested that St. John's wort, ginkgo, and echinacea at high concentrations damage reproductive cells. St. John's wort was mutagenic to sperm cells.
Time-frequency kernel design by the two-dimensional frequency transformation method

A subclass of Cohen's class of time-frequency (TF) distributions is introduced in which the TF distribution kernels are provided via the frequency transformation method (FTM), used in two dimensional (2-D) filter design. The FTM kernels have finite extent in time and frequency and allow the TF distribution to be efficiently implemented in all four domains. >
Use of Coupled Multi-Electrode Arrays to Advance the Understanding of Selected Corrosion Phenomena

Abstract The use of multi-coupled electrode arrays in various corrosion applications is discussed with the main goal of advancing the understanding of various corrosion phenomena. Both close-packed...
Tetrameric Fluorophosphazene, (NPF2)4, Planar or Puckered?

The results obtained in a comprehensive experimental study on the redetermination of the structure of N4P4F8 with single-crystal X-ray diffraction, gas electron diffraction (GED), and differential scanning calorimetry (DSC) establish clearly that, in contrast to the previous report, the eight-membered heterocycle is not planar. Above the phase transition temperature of −74 °C, the ring appears pseudoplanar. However, the N4P4 ring is disordered and is puckered above the phase transition when the disorder is modeled correctly. Below the phase transition the ring clearly resembles that of the saddle (K form) of N4P4Cl8. The unit cell of the low-temperature phase is derived from that of the higher temperature phase by doubling the c-axis and removing one-half of the symmetry elements. Full structure optimizations were performed at the HF/6-31G* and B3LYP/6-31G* levels and fully support the experimental diffraction data.
CONTINUOUS OPTICAL RESOLUTION OF (p-IODOPHENYL)GLYCINOL

ABSTRACT Enantiomeric enrichment of racemic (p-iodophenyl)glycinol was achieved with various optically active organic acids. The scalemic mixtures were further resolved by entrainment with racemic crystals of the starting material. The pure enantiomers were recovered from the mother liquor; the crystalline—almost racemic—base was recycled.
The genesis, design and effects of regional institutions: Lessons from East Asia and the Middle East

Why do regional institutions emerge, what accounts for their variation in design, and what are their effects? Several conceptual and epistemological perspectives—neorealism, neoliberal-institutionalism, constructivism, and domestic politics—provide competing and complementary answers to these questions. I focus on regional organizations as productive arenas for developing contingent propositions on institutions more generally. The purpose is to advance cross-paradigmatic dialogue in two ways: through sensitivity to scope conditions and to institutional genesis, forms, and effects, in an effort to transcend axiomatic debates that often conflate different dependent variables. The empirical analysis includes the Association of Southeast Asian Nations (ASEAN), Asia-Pacific Economic Cooperation (APEC), ASEAN Regional Forum (ARF) and the Arab League. The main findings from these cases suggest that understanding the nature of dominant domestic coalitions is often crucial for explaining incentives to create, design, and fine-tune the effects of institutions. However, this is mainly the case when the consequences of creating or designing institutions for power distribution, transaction costs, and norms are negligible or hard to estimate. In many cases these consequences are sizeable, reducing the explanatory influence of domestic coalitions. The latter often provide no more than permissive conditions for the emergence, design, and effect of institutions. Their influence is most decisive in explaining institutional genesis but is often underdetermining in explaining their design.
Transport of pollutants along the western shore of lake michigan

Oxidant production and transport along the western shore of Lake Michigan are discussed. Air quality and meteorological data were collected in this area during the summers of l976-78 using a ground-based laboratory and an instrumented aircraft. Ozone, nitrogen oxides, hydrocarbons, halocarbons, and numerous meteorological parameters were monitored continuously. Primary emissions from the Chicago and Milwaukee areas drift in northeasterly direction over the lake during morning hours. Secondary pollutants are produced in the airmass over the lake and advected onshore in the afternoon by lake winds.
On-orbit damage assessment for large space structures

The need for monitoring the dynamic characteristics of large structural systems, for the purpose of assessing the potential degradation of structural properties, has been established. This paper develops a theory for assessing the occurrence, location, and extent of potential damage utilizing on-orbit response measurements. The feasibility of the method is demonstrated using a simple structural system as an example.
Water Ice in the Kuiper Belt

We examine a large collection of low-resolution near-infrared spectra of Kuiper Belt objects (KBOs) and centaurs in an attempt to understand the presence of water ice in the Kuiper Belt. We find that water ice on the surface of these objects occurs in three separate manners: (1) Haumea family members uniquely show surfaces of nearly pure water ice, presumably a consequence of the fragmentation of the icy mantle of a larger differentiated proto-Haumea; (2) large objects with absolute magnitudes of H < 3 (and a limited number to H = 4.5) have surface coverings of water ice—perhaps mixed with ammonia—that appears to be related to possibly ancient cryovolcanism on these large objects; and (3) smaller KBOs and centaurs which are neither Haumea family members nor cold-classical KBOs appear to divide into two families (which we refer to as "neutral" and "red"), each of which is a mixture of a common nearly neutral component and either a slightly red or very red component that also includes water ice. A model suggesting that the difference between neutral and red objects due to formation in an early compact solar system either inside or outside, respectively, of the ~20 AU methanol evaporation line is supported by the observation that methanol is only detected on the reddest objects, which are those which would be expected to have the most of the methanol containing mixture.
On Minimal-Fuel Satellite Attitude Controls

A set of performance limitations is developed for a class of minimal fuel satellite attitude controls where the control torque is amplitude constrained. Both the fixed and free terminal time problems are considered. Conditions for controllability and minimal fuel controllability are derived using quantity of fuel and control time as parameters. The results are compared with those of a similar system where the control torques have been idealized to impulses.
Local strong parity violation and new possibilities in experimental study of non-perturbative QCD

Quark interaction with topologically non-trivial gluonic fields, instantons and sphalerons, violates and symmetry. In the strong magnetic field of a non-central nuclear collision such interactions lead to the charge separation along the magnetic field, the so called chiral magnetic effect, which manifests local parity violations. An experimental observation of the chiral magnetic effect would be a direct proof for the existence of such physics. Recent STAR results on charge and the reaction plane dependent correlations are consistent with theoretical expectations for the chiral magnetic effect. In this paper I discuss other approaches to experimental study of the local parity violation, and propose future measurements which can clarify the picture. In particular I propose to use central body-body U+U collisions to disentangle correlations due to chiral magnetic effect from possible background correlations due to elliptic flow. Further more quantitative studies can be performed with collision of isobaric beams.
Robust Stochastic Chemical Reaction Networks and Bounded Tau-Leaping

The behavior of some stochastic chemical reaction networks is largely unaffected by slight inaccuracies in reaction rates. We formalize the robustness of state probabilities to reaction rate deviations, and describe a formal connection between robustness and efficiency of simulation. Without robustness guarantees, stochastic simulation seems to require computational time proportional to the total number of reaction events. Even if the concentration (molecular count per volume) stays bounded, the number of reaction events can be linear in the duration of simulated time and total molecular count. We show that the behavior of robust systems can be predicted such that the computational work scales linearly with the duration of simulated time and concentration, and only polylogarithmically in the total molecular count. Thus our asymptotic analysis captures the dramatic speedup when molecular counts are large, and shows that for bounded concentrations the computation time is essentially invariant with molecular count. Finally, by noticing that even robust stochastic chemical reaction networks are capable of embedding complex computational problems, we argue that the linear dependence on simulated time and concentration is likely optimal.
Participation of sodium in the bonding of anionic networks : Synthesis, structure, and bonding of Na3MIn2 (M = Au, Ag)

Two isostructural compounds Na(3)MIn(2) (M = Au, Ag) with a NiTi(2)-type structure (Fd-3m) were synthesized via typical high-temperature reactions. The anionic M-In structure consists of tetrahedral star building units [In(4)M(4/2)] (TS) that are connected into a three-dimensional framework via shared TS vertexes, with the Na atoms filling the cages. On the basis of TB-LMTO-ASA calculations, the electronic structures of both compounds show substantial participation of sodium in the overall bonding of the structure. Compared with the Ag compound, relativistic effects in the Au phase appear to be significant, as shown in the M-M and M-Na bond length decreases of 0.03-0.04 A.
The Nature and Meaning of Perturbations in Geometric Computing

This paper addresses some fundamental questions concerning perturbations as they are used in computational geometry. How does one define them? What does it mean to compute with them? How can one compute with them? Is it sensible to use them? We define perturbations to be curves, point out that computing with them amounts to computing with limits, and (re)derive some methods of computing with such limits automatically. In principle, a line can always be used as a perturbation curve. We discuss a generic method for choosing such a line that is applicable in many situations.
Free and Polymer-Bound Tricyclic Azaphosphatranes HP(RNCH2CH2)3N+: Procatalysts in Dehydrohalogenations and Debrominations with NaH.

The commercially available nonionic base P(CH3NCH2CH2)3N (1a) was shown earlier to be superior to DBU as a stoichiometric reagent for the conversion of primary and secondary alkyl halides to alkenes (Arumugam, S.; Verkade, J. G. J. Org. Chem. 1997, 62, 4827). The precursor cation HP(CH3NCH2CH2)3N+ (2) to 1a, which is more stable and less expensive, is reported herein to be an efficient procatalyst for these reactions and also for the debromination of vicinal dibromides using NaH as a relatively inexpensive stoichiometric hydride source in CH3CN at room temperature. In dehydrohalogenations requiring more than ca. 10 h, the CH2CN- ion also acts as a base. By itself, NaH does not function well or at all under the same conditions. A catalytic cycle is proposed in which hydride deprotonates cation 2 liberating catalytic 1a. The cations HP(HNCH2CH2)3N+ (3) and HP[N(polymer)CH2CH2]N(CH2CH2NH)2+ (4) are also shown to function as procatalysts for the efficient dehydrohalogenation of RX and for the debromination of...
Implementation of continuous capnography is associated with a decreased utilization of blood gases.

Background: Capnography provides a continuous, non-invasive monitoring of the CO 2 to assess adequacy of ventilation and provide added safety features in mechanically ventilated patients by allowing for quick identification of unplanned extubation. These monitors may allow for decreased utilization of blood gases. The objective was to determine if implementation of continuous capnography monitoring decreases the utilization of blood gases resulting in decreased charges. Methods: This is a retrospective review of a quality improvement project that compares the utilization of blood gases before and after the implementation of standard continuous capnography. The time period of April 2010 to September 2010 was compared to April 2011 to September 2011. Parameters collected included total number of blood gases analyzed, cost of blood gas analysis, ventilator and patient days. Results: The total number of blood gases after the institution of end tidal CO 2 monitoring decreased from 12,937 in 2009 and 13,171 in 2010 to 8,070 in 2011. The average number of blood gases per encounter decreased from 20.8 in 2009 and 21.6 in 2010 to 13.8 post intervention. The blood gases per ventilator day decreased from 4.94 in 2009 and 4.76 in 2010 to 3.30 post intervention. The total charge savings over a 6-month period was $880,496. Conclusions: Continuous capnography resulted in a significant savings over a 6-month period by decreasing the utilization of blood gas measurements. J Clin Med Res. 2015;7(2):71-75 doi: http://dx.doi.org/10.14740/jocmr1997w
A Brief History of Long Work Time and the Contemporary Sources of Overwork

What are some of the key historical trends in hours of work per worker in US? What economic, social-psychological, organizational and institutional for- ces determine the length of individuals' working hours? How much of the trend toward longer working hours among so many workers may be attributable to workers' preferences, workplace incentives or employers' con- straints? When can work become overwork or worka- holism - an unforced addiction to incessant work activity which risk harm to workers, families or even economies? The first part of this article traces the history of the length of working hours and its recent polarization. The second part develops a multi-disciplinary model to identify motivations behind working longer hours. Individuals' desired work hours will stem from the weighted contri- bution of five sources: (1) current real wage rates; (2) forward-looking, wage trajectories; (3) relative status associated with hours of labor; (4) intrinsic rewards, process benefits or amenities acquired through work; (5) hours demanded by the employer and other structural constraints, to which workers may adapt. Employers and their established conditions of work have influenced the course of long run trends labor supply and in work time structures. The final section suggests policies that might address the persistence of long hours.
Imino-Sugar-Based Nucleosides

Continued interest in imino-sugar nucleosides derives from the observations that N-ribosyltransferases are powerfully inhibited by imino-C-nucleoside analogues that mimic the ribooxacarbenium ion nature of their transition states. The synthesis of such compounds is challenging, and synthetic routes to imino- and imino-C-nucleosides are reviewed, together with the nature of the N-ribosyltransferases that are targets for these analogues. Examples are given to exemplify the promise these compounds hold for the treatments of biological disorders.
Reversible Forms of Heart Disease

For many years the diagnosis of heart disease connoted a life of invalidism with probable death by virtue of the affliction. In recent years, however, the marked advances in medical science have not only enabled the heart patient to live a more useful life but also have shown that many forms of heart disease are entirely curable. It is important to remember that a normal heart or one that is only slightly diseased may show symptoms that are solely the expression of some extracardiac disease, and that this extracardiac condition may manifest itself entirely or largely in the cardiovascular system. As a result, the cardiac symptoms may be so marked that they completely overshadow the underlying extracardiac disease. As a result the patient is often considered a cardiac invalid, whereas recognition of the effect of the extracardiac disease with treatment directed to the extracardiac condition usually brings about a reversibility in the cardiovascular symptoms. Failure on our part to recogni e that many extracardiac diseases are expressed clinically through the cardiovascular system has led to unnecessary invalidism and even death. In every cardiac patient we must constantly be aware of the possibility that the heart itself may not be actually diseased but that rather it is acting secondarily to other conditions in the body. It is only by recognizing these extracardiac factors before they produce structural changes in the heart muscle that the treatment of the extracardiac disease may be instituted sufficiently early for the patient to be cured. It is the purpose of this paper to point out in a general way some conditions that are manifested entirely or largely through the cardiovascular system, with the result that a normal or a previously damaged heart may be precipitated into actual cardiac failure. It is apparent that all of the diseases that may produce such changes cannot be listed in the space permitted, and under these circumstances only a brief mention will be made of the various illnesses that can affect the cardiovascular system. We are familiar with the symptoms presented by the markedly obese patient. He frequently complains of dyspnea, palpitation and precordial distress. Physical examination may often reveal an
Why clashes between internal and external stability goals end in currency crises, 1797–1994

We argue that recent currency crises reflect clashes between fundamentals and pegged exchange rates, just as did crises in the past. We reject the view that crises reflect self-fulfilling prophecies that are not closely related to measured fundamentals. Doubts about the timing of a market attack on a currency are less important than the fact that it is bound to happen if a government’s policies are inconsistent with pegged exchange rates. We base these conclusions on a review of currency crises in the historical record under metallic monetary regimes and of crises post-World War II under Bretton Woods, and since, in European and Latin American pegged exchange rate regimes.
Recent advances in the stereoselective synthesis of isoprostanes and neuroprostanes

Abstract This review delineates several reported methods for the synthesis of isoprostanes and neuroprostanes with particular emphasis on the stereocontrolled construction of a suitably functionalized cyclopentane core. The α- and ω-side chains of these PG-like molecules are typically assembled by Wittig-type olefination reactions, standard transformations in the PG synthesis. The synthetic strategies include free radical cyclizations, a palladium-promoted coupling of three different components, an intramolecular cyclopropanation reaction-ring-opening sequence, a [2+2] photocycloaddition-ring-opening metathesis approach, and an intramolecular cross-coupling reaction of an alkyl iodide and a tethered alkenylsiloxane.
Quarkonium Polarization in the NRQCD Factorization Framework

The NRQCD factorization approach for calculating inclusive production of heavy quarkonium gives unambiguous predictions for the polarization of quarkonium states. The factorization formula for polarized states can be obtained by using the threshold expansion method to calculate the short-distance coefficients and then using symmetries of NRQD to reduce the NRQCD matrix elements. A particularly dramatic prediction of the NRQCD factorization framework is that prompt psi's and psi-primes's produced at the Tevatron should be predominantly transversely polarized at large transverse momentum.
Theory of a modified wadsworth monochromator matched to a low energy storage ring source

Abstract The concave diffraction grating in the Wadsworth mounting has been popular with synchrotron radiation spectroscopists because of its use of parallel light. This is well mathced to experimental stations which are a great distance away from the source as would be the case in using a high energy synchrotron. For low energy storage rings the working distance is quite small and in this case it is appropriate to use a collimating mirror. Large collection angles are possible with this arrangement and reasonable resolution can be obtained using spherical surfaces. Astigmatism is much lower than for Rowland circle mountings. These questions are analyzed using an optical path function development and calculations are presented which include the aberrations both in the two optics and those caused by the large extension of the source in the direction of the radiation emission.
Momentum transfer dynamics of a gyrostat with a discrete damper

Thestabilityofmotionofattitudemaneuversofatorque-freerigidgyrostatwithadiscretedamperisinvestigated. The equations of motion are presented in dimensionless form. Conditions for equilibrium motions and for their stability aredeveloped.Bifurcation diagramsareused toillustratethestableand unstablebranchesofsteady spins, and these bifurcation diagrams are interpreted in the slow state space of the rotor momenta and the unperturbed systemHamiltonian. Theeffectof thedampermechanismisillustratedusing a perturbed version ofthebifurcation diagram. A class of rotational maneuvers is developed based on maintaining a stationary-platform condition. This class of maneuvers maintains a small angularvelocity, which has the effect of reducing the excitation of the e exible component.
Isospectral deformations of metrics on spheres

We construct non-trivial continuous isospectral deformations of Riemannian metrics on the ball and on the sphere in Rn for every n≥9. The metrics on the sphere can be chosen arbitrarily close to the round metric; in particular, they can be chosen to be positively curved. The metrics on the ball are both Dirichlet and Neumann isospectral and can be chosen arbitrarily close to the flat metric.
Conjoint molecules of cephalosporins and aminoglycosides

A general synthetic route to conjoint molecules of cephalosporins and aminoglycosides is described. These molecules were designed as potential substrates for bacterial beta-lactamases, enzymes that hydrolyze the beta-lactam bond of cephalosporins. Hydrolysis of the beta-lactam bond was expected to release the C10-appended aminoglycoside. Since beta-lactamases are sequestered in the periplasmic space of gram-negative bacteria, this sequence of events would liberate aminoglycoside inside such bacteria. It is expected that such local delivery of aminoglycosides would circumvent the inherent toxicity of aminoglycosides that occurs during systemic exposure within the mammalian host.
Computing on Authenticated Data

In tandem with recent progress on computing on encrypted data via fully homomorphic encryption, we present a framework for computing on authenticated data via the notion of slightly homomorphic signatures, or $$P$$ P -homomorphic signatures. With such signatures, it is possible for a third party to derive a signature on the object $$m'$$ m ? from a signature of $$m$$ m as long as $$P(m,m')=1$$ P ( m , m ? ) = 1 for some predicate $$P$$ P which captures the "authenticatable relationship" between $$m'$$ m ? and $$m$$ m . Moreover, a derived signature on $$m'$$ m ? reveals no extra information about the parent $$m$$ m . Our definition is carefully formulated to provide one unified framework for a variety of distinct concepts in this area, including arithmetic, homomorphic, quotable, redactable, transitive signatures, and more. It includes being unable to distinguish a derived signature from a fresh one even when given the original signature. The inability to link derived signatures to their original sources prevents some practical privacy and linking attacks, which is a challenge not satisfied by most prior works. Under this strong definition, we then provide generic constructions for all univariate and closed predicates, and specific efficient constructions for a broad class of natural predicates such as quoting, subsets, weighted sums, averages, and Fourier transforms. To our knowledge, these are the first efficient constructions for these predicates (excluding subsets) that provably satisfy this strong security notion.
Semiparametric Theory for Causal Mediation Analysis: efficiency bounds, multiple robustness, and sensitivity analysis

Whilst estimation of the marginal (total) causal effect of a point exposure on an outcome is arguably the most common objective of experimental and observational studies in the health and social sciences, in recent years, investigators have also become increasingly interested in mediation analysis. Specifically, upon evaluating the total effect of the exposure, investigators routinely wish to make inferences about the direct or indirect pathways of the effect of the exposure not through or through a mediator variable that occurs subsequently to the exposure and prior to the outcome. Although powerful semiparametric methodologies have been developed to analyze observational studies, that produce double robust and highly efficient estimates of the marginal total causal effect, similar methods for mediation analysis are currently lacking. Thus, this paper develops a general semiparametric framework for obtaining inferences about so-called marginal natural direct and indirect causal effects, while appropriately accounting for a large number of pre-exposure confounding factors for the exposure and the mediator variables. Our analytic framework is particularly appealing, because it gives new insights on issues of efficiency and robustness in the context of mediation analysis. In particular, we propose new multiply robust locally efficient estimators of the marginal natural indirect and direct causal effects, and develop a novel double robust sensitivity analysis framework for the assumption of ignorability of the mediator variable.
A thermodynamic analysis of the Cu–Si system

Abstract Thermodynamic values for the liquid phase and phase equilibrium data of Cu–Si available in the literature were analyzed to yield a thermodynamic description of this system which is an important binary for many multicomponent technologically important alloys. In contrast to the calculated phase diagrams using descriptions available in the literature, the calculated diagram using the present one agrees with experimental data in terms of the liquidus, the solidus and the (Cu) solvus as well as the temperatures and compositions of the coexisting phases for 10 invariant equilibria. The calculated enthalpy of mixing of the liquid alloys also agrees with experimentally measured values. The intermediate phases e-Cu15Si4, η-Cu19Si6, γ-Cu56Si11 and δ-Cu33Si7 were taken to be line compounds as were done in all previous descriptions. This assumption was made since these phases have rather small ranges of homogeneity and they have minimum effects on phases in technologically important multicomponent alloys. This improved description can be used with confidence to obtain descriptions for higher order alloys.
Dispersion-managed soliton in optical fibers with zero average dispersion.

A dispersion-managed optical system with stepwise periodic variation of dispersion is studied in the framework of a path-averaged Gabitov–Turitsyn equation. The soliton solution is obtained by means of iterating the path-averaged equation. The dependence of soliton parameters on dispersion map strength is investigated, together with the oscillating tails of the soliton.
Preparation of 2(R) and 2(S) methyl-2-methylglycerates

Abstract Optically pure samples of both enantiomers of methyl 2,3-dihydroxy-2-methylpropanoate were prepared by a chromatographic separation of their (−)-menthyl esters followed by hydrolysis and methylation. Their absolute stereochemistries were established by conversion into their 3-O-acetyl derivatives, compounds of established configuration. NMR and CG-MS methods of determining the optical purities of the diols are described.
Toxic interaction between Th2 cytokines and Staphylococcus aureus in atopic dermatitis

Patients with atopic dermatitis (AD) are commonly colonized/infected with Staphylococcus aureus, and this bacterium is known to worsen the dermatitis. In this issue, Brauweiler et al. demonstrate a newly discovered mechanism by which Th2 cytokines involved in AD augment the toxicity of the lytic staphylococcal protein alpha toxin. This review presents mechanisms by which Th2 cytokines may interact with S. aureus to the detriment of the dermatitis.
The Phase Diagram of QCD and Some Issues of Large Nc

The large N c limit provides a good phenomenology of meson spectra and interactions. I discuss some problems with applying the large N c approximation to the description of baryons, and point out a number of apparent paradoxes and phenomenological difficulties
Racial differences in outcomes of triple-negative breast cancer.

African American (AA) women have a higher incidence of triple-negative breast cancer (TNBC: negative for the expression of estrogen receptor, progesterone receptor, and HER2 gene amplification) than Caucasian (CA) women, explaining in part their higher breast cancer mortality. However, there have been inconsistent data in the literature regarding survival outcomes of TNBC in AA versus CA women. We performed a retrospective chart review on 493 patients with TNBC first seen at the Washington University Breast Oncology Clinic (WUBOC) between January 2006 and December 2010. Analysis was done on 490 women (30 % AA) for whom follow-up data was available. The median age at diagnosis was 53 (23–98) years and follow-up time was 27.2 months. There was no significant difference between AA and CA women in the age of diagnosis, median time from abnormal imaging to breast biopsy and from biopsy diagnosis to surgery, duration of follow-up, tumor stage, grade, and frequency of receiving neoadjuvant or adjuvant chemotherapy and pathologic complete response rate to neoadjuvant chemotherapy. There was no difference in disease free survival (DFS) and overall survival (OS) between AA and CA groups by either univariate or multivariate analysis that included age, race, and stage. The hazard ratio for AA women was 1.19 (CI 0.80–1.78, p = 0.39) and 0.91 (CI 0.62–1.35, p = 0.64) for OS and DFS, respectively. Among the 158 patients who developed recurrence or presented with stage IV disease (AA: n = 36, CA: n = 122), no racial differences in OS were observed. We conclude that race did not significantly affect the clinical presentation and outcome of TNBC in this single center study where patients received similar therapy and follow-up.
Laminar boundary layer on a cone at incidence in supersonic flow

Results of three-dimensional boundary-layer calculations for a pointed cone and comparisons with experimental data are presented. Using a similarity transformation, the explicit dependence of the equations on axial position is removed. A further transformation is made to remove a singularity at the leeward symmetry plane. The resulting equations, in two independent variables, are then solved with an implicit finite difference technique by marching around the cone from the windward to the leeward symmetry plane. A technique for computing the edge properties from an experimental pressure distribution is developed. The comparisons with experimental data demonstrate that the theory provides an adequate representation of the viscous flow over most of the cone surface, although the physical model breaks down near the leeward symmetry plane.
Preparation and diels-alder reactions of a pyranoid vinyl glycal:model studies for anthraquinone aglycone and carbohydrate syntheses

Abstract The preparation of a conjugated pyranoid vinyl glycal is reported, along with several of its thermal [4+2] cycloaddition reactions with a variety of dienophiles. Applications to the anthraquinone antitumor agents are discussed.
Randomized, controlled trial of immediate versus delayed goal-directed ultrasound to identify the cause of nontraumatic hypotension in emergency department patients

Objective:We examined a physician-performed, goal-directed ultrasound protocol for the emergency department management of nontraumatic, symptomatic, undifferentiated hypotension.Design:Randomized, controlled trial of immediate vs. delayed ultrasound.Setting:Urban, tertiary emergency department, cens
CORRELATES OF OBJECTIVELY MEASURED PHYSICAL ACTIVITY IN PREADOLESCENT YOUTH

Abstract Objective: The purpose of this study was to identify the psychosocial and environmental correlates of objectively measured physical activity behavior in a diverse sample of sixth-grade students. Design: Cross-sectional. Participants and Setting: One hundred ninety-eight sixth-grade students from 4 public middle schools in Columbia, South Carolina. The study group was 52.0% female, 55.1% African-American, with a mean age of 11.4 ± 0.6 years. Main Outcome Measures: Time spent in moderate physical activity (MPA) and vigorous physical activity (VPA) was assessed using a uniaxial accelerometer (CSA WAM 7164) (Computer Science and Applications Inc., Shalimar, FL). Determinant variables included: age, gender, race/ethnicity (demographic); physical activity self-efficacy, social norms related to physical activity, and beliefs regarding physical activity outcomes (psychosocial); and perceived physical activity habits of parents and peers, involvement in community physical activity organizations, involvement in community-based sports programs, access to fitness/sporting equipment at home, and self-reported hours spent watching television or playing video games (environmental). Results: For boys, physical activity self-efficacy, social norms related to physical activity, and involvement in community physical activity organizations were salient predictors of MPA and VPA. Among girls, only physical activity self-efficacy emerged as a clear predictor of objectively measured physical activity. Conclusions: These findings are consistent with previous studies using self-reported physical activity and suggest that interventions to increase physical activity in preadolescent youth should endeavor to boost physical activity self-efficacy by offering a wide selection of enjoyable, developmentally-appropriate physical activity options.