cssi/SciSciGPT-SciSciNet huggingface dataset:
Interfacial stability of CoSi2/Si structures grown by molecular beam epitaxy

The stability of CoSi2/Si interfaces was examined in this study using columnar silicide structures grown on (111) Si substrates. In the first set of experiments, Co and Si were codeposited using MBE at 800 C and the resulting columnar silicide layer was capped by epitaxial Si. Deposition of Co on the surface of the Si capping layer at 800 C results in the growth of the buried silicide columns. The buried columns grow by subsurface diffusion of the deposited Co, suppressing the formation of surface islands of CoSi2. The column sidewalls appear to be less stable than the top and bottom interfaces, resulting in preferential lateral growth and ultimately in the coalescence of the columns to form a continuous buried CoSi2 layer. In the second set of experiments, annealing of a 250 nm-thick buried columnar layer at 1000 C under a 100 nm-thick Si capping layer results in the formation of a surface layer of CoSi2 with a reduction in the sizes of the CoSi2 columns. For a sample having a thicker Si capping layer the annealing leads to Ostwald ripening producing buried equiaxed columns. The high CoSi2/Si interfacial strain could provide the driving force for the observed behavior of the buried columns under high-temperature annealing.
Synthesis of new chiral tetradentate sulfonamide based ligands

Abstract A two step procedure for the synthesis of chiral tetradentate sulfonamide ligands is reported. The ligands are easily prepared from the corresponding bissulfonamide complexes by directed metallation followed by quenching with either ketones or carbon dioxide in 47 to 82 % yield. Preliminary results indicate that these complexes are efficient catalysts in the asymmetric addition of alkyl groups to aldehydes.
Under what circumstances, past and present, have international rescues of countries in financial distress been successful?

Recent events in Asia and other parts of the globe have prompted calls from many quarters for international rescue of the monetary or fiscal authorities in distressed countries. We contrast the experience of rescues of monetary authorities before 1973 of advanced countries temporarily short of liquidity with recent experience of bailouts. International rescues in the past have involved relatively small amounts of money, sufficient to stave off devaluation or abandonment of a fixed exchange rate while remedial policies were put in place. Recent bailouts have involved handing over relatively large amounts to both foreign lenders and domestic investors after devaluation of a pegged exchange rate to avoid their incurring wealth losses. We document past rescues, whether successful or unsuccessful, by monetary regimes, and show what is different today from past experience.
A CONFLICT MODEL AND INTERACTIVE SIMULATOR (FASTCARS) FOR PREDICTING ENROUTE DRIVER BEHAVIOR IN RESPONSE TO REAL-TIME TRAFFIC CONDITION INFORMATION

This paper proposes a theoretical methodology and practical data collection approach for modeling enroute driver behavioral choice under Advanced Traveler Information Systems (ATIS). The theoretical framework is based on conflict assessment and resolution theories popularized in psychology and applied to models of individual consumer behavior. It is posed that enroute assessment and adjustment is a reactionary process influenced by increased conflict arousal and motivation to change. When conflict rises to a level at which conflict exceeds a personal threshold of tolerance, drivers are likely to alter enroute behavior to alleviate conflict through either route diversion of goal revision. Assessment and response to conflict arousal directly relate to the driver's abilities to perceive and predict network conditions in conjunction with familiarity of network configurations and accessible alternate routes.
New Synthetic Amino Acids for the Design and Synthesis of Peptide-Based Metal Ion Sensors

The syntheses of two new nonstandard amino acids, Flu (6) and XBp (20), and a new synthesis of Dmd (12) are reported. These residues exhibit fluorescence, metal-coordination, and fluorescence-quenching properties, respectively. These building blocks have been incorporated into peptides via solid phase peptide synthesis to afford the prototype for a photoinduced electron transfer-based metal ion chemosensor. The fluorescence of the peptides is modulated upon metal binding. This results from a metal ion-induced conformational change that brings the side chains of the Flu and Dmd amino acids into proximity, thereby favoring photoinduced electron transfer (PET) fluorescence quenching.
StarL: Towards a Unified Framework for Programming, Simulating and Verifying Distributed Robotic Systems

We developed StarL as a framework for programming, simulating, and verifying distributed systems that interacts with physical processes. StarL framework has (a) a collection of distributed primitives for coordination, such as mutual exclusion, registration and geocast that can be used to build sophisticated applications, (b) theory libraries for verifying StarL applications in the PVS theorem prover, and (c) an execution environment that can be used to deploy the applications on hardware or to execute them in a discrete event simulator. The primitives have (i) abstract, nondeterministic specifications in terms of invariants, and assume-guarantee style progress properties, (ii) implementations in Java/Android that always satisfy the invariants and attempt progress using best effort strategies. The PVS theories specify the invariant and progress properties of the primitives, and have to be appropriately instantiated and composed with the application's state machine to prove properties about the application. We have built two execution environments: one for deploying applications on Android/iRobot Create platform and a second one for simulating large instantiations of the applications in a discrete even simulator. The capabilities are illustrated with a StarL application for vehicle to vehicle coordination in an automatic intersection that uses primitives for point-to-point motion, mutual exclusion, and registration.
Field topologies in ideal and near-ideal magnetohydrodynamics and vortex dynamics

Magnetic field topology frozen in ideal magnetohydrodynamics (MHD) and its breakage in near-ideal MHD are reviewed in two parts, clarifying and expanding basic concepts. The first part gives a physically complete description of the frozen field topology derived from magnetic flux conservation as the fundamental property, treating four conceptually related topics: Eulerian and Lagrangian descriptions of three dimensional (3D) MHD, Chandrasekhar-Kendall and Euler-potential field representations, magnetic helicity, and inviscid vortex dynamics as a fluid system in physical contrast to ideal MHD. A corollary of these developments clarifies the challenge of achieving a high degree of the frozen-in condition in numerical MHD. The second part treats field-topology breakage centered around the Parker Magnetostatic Theorem on a general incompatibility of a continuous magnetic field with the dual demand of force-free equilibrium and an arbitrarily prescribed, 3D field topology. Preserving field topology as a global constraint readily results in formation of tangential magnetic discontinuities, or, equivalently, electric current-sheets of zero thickness. A similar incompatibility is present in the steady force-thermal balance of a heated radiating fluid subject to an anisotropic thermal flux conducted strictly along its frozen-in magnetic field in the low-β limit. In a weakly resistive fluid the thinning of current sheets by these general incompatibilities inevitably results in sheet dissipation, resistive heating and topological changes in the field notwithstanding the small resistivity. Strong Faraday induction drives but also macroscopically limits this mode of energy dissipation, trapping or storing free energy in self-organized ideal-MHD structures. This property of MHD turbulence captured by the Taylor hypothesis is reviewed in relation to the Sun’s corona, calling for a basic quantitative description of the breakdown of flux conservation in the low-resistivity limit. A cylindrical initial-boundary value problem provides specificity in the general MHD ideas presented.
Fault-tolerant wait-free shared objects

Wait-free implementations of shared objects tolerate the failure of processes, but not the failure of base objects from which they are implemented. We consider the problem of implementing shared objects that tolerate the failure of both processes and base objects.We identify two classes of object failures: responsive and nonresponsive. With responsive failures, a faulty object responds to every operation, but its responses may be incorrect. With nonresponsive failures, a faulty object may also “hang” without responding. In each class, we define crash, omission, and arbitrary modes of failure.We show that all responsive failure modes can be tolerated. More precisely, for all responsive failure modes ℱ, object types T, and t ≥ 0, we show how to implement a shared object of type T which is t-tolerant for ℱ. Such an object remains correct and wait-free even if up to t base objects fail according to ℱ. In contrast to responsive failures, we show that even the most benign non-responsive failure mode cannot be tolerated. We also show that randomization can be used to circumvent this impossibility result.Graceful degradation is a desirable property of fault-tolerant implementations: the implemented object never fails more severely than the base objects it is derived from, even if all the base objects fail. For several failure modes, we show wheter this property can be achieved, and, if so, how.
Global Existence and Finite Time Blow-Up for Critical Patlak-Keller-Segel Models with Inhomogeneous Diffusion

The $L^1$-critical parabolic-elliptic Patlak--Keller--Segel system is a classical model of chemotactic aggregation in microorganisms well known to have critical mass phenomena [Blanchet, Dolbeault, and Perthame, Electron. J. Differential Equations, 2006 (2006), pp. 1--23; Blanchet, Carrillo, and Laurencot, Calc. Var., 35 (2009), pp. 133--168]. In this paper we study this critical mass phenomenon in the context of Patlak--Keller--Segel models with spatially varying diffusivity of the chemoattractant. The primary issue is how, if possible, one localizes the presence of the inhomogeneity in the nonlocal term. Our methods also provide new blow-up results for the homogeneous problem with nonlinear diffusion, showing that there exist blow-up solutions with arbitrarily large (positive) initial free energy.
A systematic analysis of diversion: Net widening and beyond

Abstract This analysis focuses on the operation of a juvenile diversion program in a large metropolitan area. In particular, the impact of the program on referrals made by the police to the juvenile court is examined. Consistent with most studies of diversion, a significant amount of net widening was found to occur following the introduction of the program. A time-series design using a four-year-preprogram and four-year-program period was employed to examine the trends in processing over time. Referrals for all categories of offenses rose significantly during the program years. The implications of these results are discussed in light of both police commitment to the goals of diversion and the legal safeguards in juvenile processing.
ON THE TWISTED (2,0) AND LITTLE-STRING THEORIES

Abstract We study the compactification of the (2, 0) and type-II little-string theories on S 1 , T 2 and T 3 with an R-symmetry twist that preserves half the supersymmetry. We argue that it produces the same moduli spaces of vacua as compactification of the (1, 0) theory with E 8 Wilson lines given by a maximal embedding of SU (2). In certain limits, this reproduces the moduli space of SU (2) with a massive adjoint hyper-multiplet. In the type-II little-string theory case, we observe a peculiar phase transition where the strings condense. We conjecture a generalization to more than two 5-branes which involves instantons on non-commutative T 4 . We conclude with open questions.
Three-dimensional aerodynamic shape optimization using discrete sensitivity analysis

An aerodynamic shape optimization procedure based on discrete sensitivity analysis is extended to treat three-dimensional geometries. The function of sensitivity analysis is to directly couple computational fluid dynamics (CFD) with numerical optimization techniques, which facilitates the construction of efficient direct-design methods. The development of a practical three-dimensional design procedures entails many challenges, such as: (1) the demand for significant efficiency improvements over current design methods; (2) a general and flexible three-dimensional surface representation; and (3) the efficient solution of very large systems of linear algebraic equations. It is demonstrated that each of these challenges is overcome by: (1) employing fully implicit (Newton) methods for the CFD analyses; (2) adopting a Bezier-Bernstein polynomial parameterization of two- and three-dimensional surfaces; and (3) using preconditioned conjugate gradient-like linear system solvers. Whereas each of these extensions independently yields an improvement in computational efficiency, the combined effect of implementing all the extensions simultaneously results in a significant factor of 50 decrease in computational time and a factor of eight reduction in memory over the most efficient design strategies in current use. The new aerodynamic shape optimization procedure is demonstrated in the design of both two- and three-dimensional inviscid aerodynamic problems including a two-dimensional supersonic internal/external nozzle, two-dimensional transonic airfoils (resulting in supercritical shapes), three-dimensional transport wings, and three-dimensional supersonic delta wings. Each design application results in realistic and useful optimized shapes.
Reconstructing pathways in large genetic networks from genetic perturbations.

I present an algorithm that determines the longest path between every gene pair in an arbitrarily large genetic network from large scale gene perturbation data. The algorithm's computational complexity is O(nk2), where n is the number of genes in the network and k is the average number of genes affected by a genetic perturbation. The algorithm is able to distinguish a large fraction of direct regulatory interactions from indirect interactions, even if the accuracy of its input data is substantially compromised.
Religious and Secular Coping Strategies and Mortality Risk among Older Adults

Using data from the Wisconsin Longitudinal Study, the purpose of this study is twofold. First, the study identifies coping strategies used by older adults. Second, the study examines the impact of older adults’ chosen coping strategies on mortality reduction. The study focuses specifically on differences in the use of religious and secular coping strategies among this population. The findings suggest that although coping strategies differ between those who self-classify as religious and those who self-classify as nonreligious, for both groups social approaches to coping (e.g., attending church and volunteering) are more likely than individual approaches (e.g., praying or active/passive coping) to reduce the risk of mortality. The most efficacious coping strategies, however, are those matched to characteristics of the individual.
Fundamental strings as noncommutative solitons

The interpretation of closed fundamental strings as solitons in open string field theory is reviewed. Noncommutativity is introduced to facilitate an explicit construction. The tension is computed exactly and the correct spectrum is recovered at long wave length.
Uniform asymptotic description of ultrashort Gaussian-pulse propagation in a causal, dispersive dielectric.

The complete asymptotic description of ultrashort Gaussian-pulse propagation in a single-resonance Lorentz medium in the mature-dispersion regime is presented and compared with the results of two independent numerical experiments of the propagated-field evolution. The nonuniform asymptotic method of Olver [Stud. Appl. Math. Rev. 12, 228 (1970)] (an extension of the method of steepest descents) is first applied to obtain the standard asymptotic description of the propagated field that is due to the given input Gaussian-modulated field. The description afforded by this asymptotic method, although nonuniform in certain space-time regions, is found to be in excellent agreement with purely numerical results, especially when exact, numerically determined saddle-point locations, and exact expressions for the derivatives of the phase function are used in the implementation of the theoretical approach. Modern uniform asymptotic techniques, which generalize Olver's nonuniform description, are then employed to obtain a rigorous description of ultrashort Gaussian-pulse propagation that is uniformly valid for all space-time points in the mature-dispersion regime. This asymptotic description clearly shows that the propagated field can be expressed solely in terms of a generalized Sommerfeld and a generalized Brillouin precursor field, the first of which dominates the total propagated field when the carrier frequency ${\mathrm{\ensuremath{\omega}}}_{\mathit{c}}$ is well above resonance while the second generalized precursor field dominates when ${\mathrm{\ensuremath{\omega}}}_{\mathit{c}}$ is below or near resonance. It is further shown that the pulse distortion is due solely to the manner in which the precursor field amplitude is modified by the initial Gaussian-pulse envelope spectrum. Finally, the frequency dependence of the signal velocity of the input ultrashort, Gaussian-modulated harmonic field in a single-resonance Lorentz medium is discussed.
Static and Dynamic Behavior of Highly Deformed Risers and Pipelines

This paper models flexible risers and pipelines as slender elastica structures. The theoretical formulation leads to a type of nonlinear boundary value problem that can be solved numerically given appropriate boundary conditions. The offsetting effects of gravity and buoyancy are included in the analysis. These forces can provide considerable axial loading (as can thermal changes), and hence, stability (buckling) is a major concern. Initial studies are based on the planar problem. A free-vibration analysis is also conducted for small-amplitude oscillations about various deflected equilibrium configurations in terms of natural frequencies and corresponding mode shapes. Energy dissipation and fluid forces are key issues in the forced problem, especially when large deformations are involved. Free vibration information is a vital prerequisite in understanding the response of these types of structures in practice.
Charge-transfer spectroscopy and photochemistry of alkylamine cobalt(III) complexes

Abstract Spectroscopic and photochemical studies are reported for Co(NH2R)63+, Co(NH2R)5OH23+, and Co(NH2R)5X2+ (where R is methyl, ethyl, or n-propyl, and X is Cl− or Br−). These complexes absorb strongly in the ultraviolet region owing to the presence of one or more ligand-to-metal charge transfer (LMCT) band(s). Irradiation into this charge transfer region results in redox decomposition of the complex with the release of Co2+, alkylamine, and a radical. Photoredox quantum yields measured in fluid solution are generally high and dependent upon excitation wavelength, oxygen concentration, temperature, and solution viscosity. In contrast to their well-studied ammine analogues, the alkylamine complexes (1) possess a N → Co charge transfer band at wavelengths well above 200 nm, (2) undergo redox decomposition from the X → Co and N → Co charge transfer excited states, and (3) avoid an intermolecular decomposition pathway involving photooxidation of the solvent. Reasons for these differences between the two families of complexes are discussed.
Generalized Hilbert Functions

Let M be a finite module, and let I be an arbitrary ideal over a Noetherian local ring. We define the generalized Hilbert function of I on M using the zeroth local cohomology functor. We show that our definition reconciliates with that of Ciuperca. By generalizing Singh's formula (which holds in the case of λ(M/IM) < ∞), we prove that the generalized Hilbert coefficients &#x1d527;0,…, &#x1d527; d−2 are preserved under a general hyperplane section, where d = dim M. We also keep track of the behavior of &#x1d527; d−1. Then we apply these results to study the generalized Hilbert function for ideals that have minimal j-multiplicity or almost minimal j-multiplicity. We provide counterexamples to show that the generalized Hilbert series of ideals having minimal or almost minimal j-multiplicity does not have the ‘expected’ shape described in the case where λ(M/IM) < ∞. Finally, we give a sufficient condition such that the generalized Hilbert series has the desired shape.
Computing homotopic shortest paths in the plane

We address the problem of computing homotopic shortest paths in presence of obstacles in the plane. The problems on homotopy of the paths received attention very recently [3, 8]. We present two output-sensitive algorithms, for simple paths and non-simple paths. The algorithm for simple paths improves the previous algorithm [8]. The algorithm for non-simple paths achieves O(log2n) time per output vertex which is an improvement by a factor of O(n/log2n) of the previous algorithm [13] where n is the number of obstacles.
Accessible medical equipment for patients with disabilities in primary care clinics: why is it lacking?

Abstract Background Previous research has identified inaccessible medical equipment as a barrier to health care services encountered by people with disabilities. However, no research has been conducted to understand why medical practices lack accessible equipment. Objectives/hypothesis The purpose of this study was to examine practice administrators' knowledge of accessible medical equipment and cost of accessible medical equipment to understand why medical practices lack such equipment. Hypotheses were: 1) Practice administrators lacked knowledge about accessible medical equipment and 2) The cost of accessible medical equipment was too great compared to standard equipment for the clinic. Methods This study was a mixed methods survey of primary care practice administrators. The sixty-three participates were members of a medical management organization. Data were collected between December 20, 2011 and January 17, 2012. Proportions, Guttman scalogram, and Spearman's Rho correlation analyses were utilized. Results For this sample, less than half of the administrators knew that accessible equipment existed and a fourth knew what accessible equipment existed. There was a significant (p Conclusion Practice administrators' lack of knowledge of accessible medical equipment emphasizes the need not only for more education about the availability of accessible equipment but also about the importance of accessible equipment for their patients with disabilities and for physicians who provide them care.
Emerging host-guest chemistry of synthetic nanotubes.

Emerging host–guest chemistry of synthetic nanotubes is reviewed, including the preparation of their encapsulation complexes, guest dynamics, exchange and potential applications.
Synthesis of 9-Substituted Xanthenes by the Condensation of Arynes with ortho-Hydroxychalcones.

Abstract The reaction of o -(trimethylsilyl)aryl triflates, CsF, and o -hydroxychalcones affords a general and efficient way to prepare biologically interesting 9-substituted xanthenes. This chemistry presumably proceeds by the tandem intermolecular nucleophilic attack of the phenoxide of the chalcone on the aryne and subsequent intramolecular Michael addition. The introduction of an external base, Cs 2 CO 3 , has proven beneficial in this reaction.
After Developmentalism and Globalization, What?

In 1900, in preparation for the Exposition Universelle in Paris, the French Ministry of Colonies asked Camille Guy, the head of its geographical service, to produce a book entitled Les colonies francaises: la mise en valeur de notre domaine coloniale. A literal translation of mise en valeur is “making into value.” The dictionary, however, translates “mise en valeur” as “development.” At the time, this expression was preferred, when talking about economic phenomena in the colonies, to the perfectly acceptable French word, “developpement.” If one then goes to Les Usuels de Robert: Dictionnaire des Expressions et Locutions fi gurees (1979) to learn more about the meaning of the expression “mettre en valeur,” one fi nds the explanation that it is used as a metaphor meaning “to exploit, draw profi t from.” Basically, this was the view of the pan-European world during the colonial era concerning economic development in the rest of the world. Development was a set of concrete actions effectuated by Europeans to exploit and draw profi t from the resources of the non-European world. There were a number of assumptions in this view: Non-Europeans would not be able or perhaps even willing to “develop” their resources without the active intrusion of the pan-European world. But such development represented a material and moral good for the world. It was therefore the moral and political duty of the pan-Europeans to exploit the resources of these countries. There was consequently nothing wrong with the fact that, as a reward, the pan-Europeans who exploited the resources drew profi t from them, since a secondary advantage would go to the persons whose resources were being exploited in this way. This rationale of course completely omitted discussion of the cost in life and limb to the local people of such exploitation. The conventional calculus was that these costs were, as we would say in today’s euphemisms, the necessary and inevitable “collateral damage” of Europe’s “civilizing mission.” The tone of the discussion began to change after 1945, primarily as a result of the strength of anticolonial sentiments and movements in Asia and Africa,
Shrunken Locally Linear Embedding for Passive Microwave Retrieval of Precipitation

This paper introduces a new Bayesian approach to the inverse problem of passive microwave rainfall retrieval. The proposed methodology [called the shrunken locally linear embedding algorithm for retrieval of precipitation (ShARP)] relies on a regularization technique and makes use of two joint dictionaries of coincident rainfall profiles and their corresponding upwelling spectral radiative fluxes. A sequential detection–estimation strategy is adopted, which basically assumes that similar rainfall intensity values and their spectral radiances live close to some sufficiently smooth manifolds with analogous local geometry. The detection step employs a nearest neighbor classification rule, whereas the estimation scheme is equipped with a constrained shrinkage estimator to ensure the stability of retrieval and some physical consistency. The algorithm is examined using coincident observations of the active precipitation radar and the passive microwave imager onboard the TRMM satellite. We present promising results of instantaneous rainfall retrieval for some tropical storms and mesoscale convective systems over ocean, land, and coastal zones. We provide evidence that the algorithm is capable of properly capturing different storm morphologies including high-intensity rain cells and trailing light rainfall, particularly over land and coastal areas. The algorithm is also validated at an annual scale for calendar year 2013 versus the standard (version 7) radar (2A25) and radiometer (2A12) rainfall products of the TRMM satellite.
Estimating the precision of welfare measures

Abstract Three methods for constructing standard deviation and/or confidence intervals for welfare estimates have been employed in the recreation demand literature: a Taylor's series approximation, the bootstrap, and a method proposed by Krinsky and Robb. This paper presents the results of two sets of simulation experiments designed to examine the accuracy of these methods. The first simulation examines the methods' accuracy in estimating the standard deviation of welfare estimates; the second simulation examines the accuracy of the methods in constructing confidence intervals.
Stability and absence of binding for multi-polaron systems

We resolve several longstanding problems concerning the stability and the absence of multi-particle binding for N ≥ 2 polarons. Frohlich’s 1937 polaron model describes non-relativistic particles interacting with a scalar quantized field with coupling √ɑ, and with each other by Coulomb repulsion of strength U. We prove the following: (i)While there is a known thermodynamic instability for U 2ɑ, that is, the ground state energy per particle has a finite limit as N → ∞. (ii) There is no binding of any kind if U exceeds a critical value that depends on ɑ but not on N. The same results are shown to hold for the Pekar-Tomasevich model.
Computation and analysis of multiple structural change models

In a recent paper, Bai and Perron (1998) considered theoretical issues related to the limiting distribution of estimators and test statistics in the linear model with multiple structural changes. In this companion paper, we consider practical issues for the empirical applications of the procedures. We first address the problem of estimation of the break dates and present an efficient algorithm to obtain global minimizers of the sum of squared residuals. This algorithm is based on the principle of dynamic programming and requires at most least-squares operations of order O(T2) for any number of breaks. Our method can be applied to both pure and partial structural change models. Second, we consider the problem of forming confidence intervals for the break dates under various hypotheses about the structure of the data and the errors across segments. Third, we address the issue of testing for structural changes under very general conditions on the data and the errors. Fourth, we address the issue of estimating the number of breaks. Finally, a few empirical applications are presented to illustrate the usefulness of the procedures. All methods discussed are implemented in a GAUSS program. Copyright © 2002 John Wiley & Sons, Ltd.
Examining the long-run effect of money on economic growth

Abstract Christiano and Ljungqvist (1988) find a statistically significant Granger-causal relation between money and output when data are measured in log levels, but not when they use data in log differences. To resolve this puzzle, we develop an endogenous growth model with money to study the long-run interactions between real and monetary sectors. Money is regarded as a Hicks-neutral technological factor that improves the efficiency of goods production. We examine the effects of anticipated inflation on the growth rates of real macroeconomic variables and find that money is “superneutral” in the growth rate sense.
Pregnancy in patients with cystic fibrosis

Abstract As more patients with cystic fibrosis reach adulthood, questions arise about the potential hazards of pregnancy. We reviewed the medical records of eight women with cystic fibrosis who had...
A chance-constrained two-stage stochastic program for unit commitment with uncertain wind power output

In this paper, we present a unit commitment problem with uncertain wind power output. The problem is formulated as a chance-constrained two-stage (CCTS) stochastic program. Our model ensures that, with high probability, a large portion of the wind power output at each operating hour will be utilized. The proposed model includes both the two-stage stochastic program and the chance-constrained stochastic program features. These types of problems are challenging and have never been studied together before, even though the algorithms for the two-stage stochastic program and the chance-constrained stochastic program have been recently developed separately. In this paper, a combined sample average approximation (SAA) algorithm is developed to solve the model effectively. The convergence property and the solution validation process of our proposed combined SAA algorithm is discussed and presented in the paper. Finally, computational results indicate that increasing the utilization of wind power output might increase the total power generation cost, and our experiments also verify that the proposed algorithm can solve large-scale power grid optimization problems.
Do futures lead price discovery in electronic foreign exchange markets

Using intraday data, this study investigates the contribution to the price discovery of Euro and Japanese Yen exchange rates in three foreign exchange markets based on electronic trading systems: the CME GLOBEX regular futures, E-mini futures, and the EBS interdealer spot market. Contrary to evidence in equity markets and more recent evidence in foreign exchange markets, the spot market is found to consistently lead the price discovery process for both currencies during the sample period. Furthermore, E-mini futures do not contribute more to the price discovery than the electronically traded regular futures. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 29:137–156, 2009
Tethers and asteroids for artificial gravity assist in the solar system

Analytical models are defined for gravity-assist trajectory changes for spacecraft passing massive compact bodies. The models are applied in an examination of the benefits of lowering a tether to an asteroid during a flyby in order to gain a trajectory change equivalent to that from a massive body (planet). Direct flybys yield velocity gains while retrograde flybys shed velocity. The magnitude of the effects are a function of the proximity to the body during flyby. This inherently limits the gravity assist technique used around planets, which usually have atmospheres and can have intense radiation fields. If a spacecraft could extend a tether (such as to be tested on the Orbiter) to snag on an asteroid surface, the potential trajectory/velocity change of the spacecraft would be limited mainly by the tether strength. The encounter physics are treated as a soft collision. Possible applications of the asteroid tether technique are outer planet, Mars and main belt asteroid exploration missions.
Generative systems of analyzers

It is argued that human visual analyzers are organized into generative systems and that these systems are decomposed into nested structures of control. Any such system is structured as a transformation group G and the nested analyzer hierarchy can be expressed by an algebraic decomposition G 1 . G 2 . … . G n of that group. The paper shows how several important aspects of this analyzer architecture determine several important aspects of any perceptual organization. For example, there is a division of the analyzer hierarchy into two sub-hierarchies, one encoding the stimulus set as generated via a sequence of successively modified prototypes, and the other encoding the stimulus set as generated internally from a subset. The structure of the latter analyzer sub-hierarchy is responsible for the encoding of grouping in the stimulus set. Principles are proposed that determine the way these two analyzer sub-hierarchies are wired together: symmetry axis analyzers of the grouping sub-hierarchy are wired as encoding lines of flexibility in the sub-hierarchy describing the percept as deformed via a sequence of prototypes. In addition, it is found that one particular example of such a combined structure is significantly salient across many perceptual organizational situations. Several aspects of its architecture are examined, and it is found to provide us with a detailed theory of the perceptual encoding of highly complex shape.
The Turbulent Cascade at 1 AU: Energy Transfer and the Third-Order Scaling for MHD

We perform a test of MHD turbulent cascade theory in the solar wind and directly evaluate the contribution of local turbulence to heating the solar wind at 1 AU. We look at turbulent fluctuations in the solar wind velocity V and magnetic field B, using the vector Elsasser variables Z ± ≡ V ± B/(4πρ)1/2 as measured at the ACE spacecraft stationed at the Earth's L1 point. We combine the fluctuations δZ± over time lags in the inertial range, from 64 s to several hours, to form components of the mixed vector third moments, and we adopt the work of Politano & Pouquet, who derive an exact scaling law, similar to the Kolmogorov 4/5 law, but valid in anisotropic MHD turbulence, for these components. We demonstrate that the scaling is reasonably linear, as is expected for the inertial range. The total turbulent energy injection/dissipation rate that we derive this way agrees with the in situ heating of the solar wind that is inferred from the temperature gradient, whereas methods using the power spectra only seldom agree with the heating rates derived from gradients of the thermal proton distribution. We derive expressions of the third-order moments that are applicable to the spectral cascades parallel and perpendicular to the mean magnetic field. We apply these expressions to fast- and slow-wind subsets of the data, with additional subsetting for mean field direction. We find that both the fast wind and the slow wind exhibit an active energy cascade over the inertial range scales. Furthermore, we find that the energy flux in the parallel cascade is consistently smaller than in the perpendicular cascade.
DOES PUBLIC CAPITAL CROWD OUT PRIVATE CAPITAL

Abstract The central focus of this paper is on the question: does higher public capital accumulation ‘crowd out’ private investment? Higher public capital accumulation raises the national investment rate above the level chosen by rational agents and induces an ex ante crowding out of private investment. However, an increase in the public capital stock also raises the return to private capital, which crowds in private capital accumulation. Empirical evidence on the net effect of these opposing forces is presented.
Sequential market basket analysis

Market basket analysis (MBA) is a powerful and common practice in modern retailing that has some limitations stemming from the fact that it infers purchase sequence from joint-purchasing data. However, internet retailers automatically collect purchase-sequence data from their shoppers, and new technology is available for traditional (bricks and mortar) retailers to do the same, making it possible to analyze purchase sequences, rather than inferring them from joint purchases. This study first compares and contrasts traditional market basket analysis with a sequential extension, and then proposes a framework for purchase-sequence analysis, which is illustrated utilizing shopping trip data from one grocery store.
Characterizations of core-shell nanoparticle catalysts for methanol electrooxidation

This paper describes the results of an investigation of the structure and composition of core-shell gold and alloy nanoparticles as catalytically active nanomaterials for potential fuel cell catalysis. Centered on the electrocatalytic methanol oxidation, we show three sets of results based on electrochemical, surface, and composition characterizations. First, electrochemical studies have revealed that the nanostructured catalysts are active towards the electrooxidation of methanol and carbon monoxide. Second, X-ray photoelectron spectroscopy (XPS) data have shown that the organic encapsulating shells can be effectively removed electrochemically or thermally, which involves the formation of oxides on the nanocrystals. Thirdly, direct current plasma - atomic emission spectrometry (DCP-AES) has revealed insights for the correlation of the composition of alloy nanoparticles with the catalytic activities. Implications of these results to the design of nanostructured catalysts will also be discussed.
Iron(II) bromide-catalyzed synthesis of benzimidazoles from aryl azides.

The identity of the ortho-substituent of an aryl azide influences its reactivity toward transition metals. Substitution of a vinyl group with an imine disables rhodium(II)-mediated C−H amination and triggers a Lewis acid mechanism catalyzed by iron(II) bromide to facilitate benzimidazole formation.
Cu‐Catalyzed Chemoselective Preparation of 2‐(Pinacolato)boron‐Substituted Allylcopper Complexes and their In Situ Site‐, Diastereo‐, and Enantioselective Additions to Aldehydes and Ketones

Transformations that entail catalytic generation of reactive entities for in situ use in stereoselective synthesis are in high demand;[1] such processes are more efficient and operationally simpler than when a priori preparation and purification of stoichiometric quantities of sensitive intermediates are required.[2] Successful design of multi-component pathways hinges on high chemoselectivity: A starting material and a reagent must first be catalytically transformed into a new species, which then has to undergo reaction with another substrate. If the catalyst structure is incorporated within the intermediate molecule, reactivity and selectivity can be further controlled. When one or both partners carry several potentially reactive sites, other issues of selectivity must be addressed. Matters of efficiency and site- and/or stereoselectivity need to be resolved at every stage, and conditions must be found to ensure facile catalyst turnover.
Noradrenergic control of circadian rhythms in Cebus albifrons.

Manifestation of biologic oscillations (e.g., body temperature 24-hour wave form) is the summation of the exogenous and endogenous response mechanisms of the biologic clock. Biologic rhythm asynchrony results from a rapid change in the environment presented to the time sensors. The destruction of noradrenergic terminals in a male Cebus albifrons by 6-hydroxydopa interrupted the transmission of information from the defined environment to the biologic clock as evidenced by removal of the exogenous components of the 24-hour deep body-temperature (DBT) wave form; i.e., decrease in DBT rhythm was no longer associated to lights off, and the level about which this rhythm fluctuated was reduced. In contrast the daily heart rate rhythm was less affected.
Type IIA superstrings, chiral symmetry, and N = 1 4D gauge theory dualities

Abstract We study N = 1 four-dimensional gauge theories as the world-volume theory of D4-branes between NS 5-branes. We find constructions for a number of known field theory dualities involving SU(Nc) × SU(N′c) groups, coupled by matter fields F in the (N c , N − c ) representation, in terms of branes of type IIA string theory. The dual gauge group follows from simply reversing the ordering of the NS 5-branes and the D6-branes while conserving magnetic charge on the world-volume of the branes. We interpret many field theory phenomena such as deformation of the superpotential W = Tr (F F ) k+1 in terms of the position of branes. By looking to D-branes for guidance, we find new N = 1 dualities involving arbitrary numbers of gauge groups. We propose a mechanism for enhanced chiral symmetry in the brane construction which, we conjecture, is associated with tensionless 3-branes in six dimensions.
Caching Eliminates the Wireless Bottleneck in Video Aware Wireless Networks

Wireless video is the main driver for rapid growth in cellular data traffic. Traditional methods for network capacity increase are very costly and do not exploit the unique features of video, especially asynchronous content reuse. In this paper we give an overview of our work that proposed and detailed a new transmission paradigm exploiting content reuse and the widespread availability of low-cost storage. Our network structure uses caching in helper stations (femtocaching) and/or devices, combined with highly spectrally efficient short-range communications to deliver video files. For femtocaching, we develop optimum storage schemes and dynamic streaming policies that optimize video quality. For caching on devices, combined with device-to-device (D2D) communications, we show that communications within clusters of mobile stations should be used; the cluster size can be adjusted to optimize the tradeoff between frequency reuse and the probability that a device finds a desired file cached by another device in the same cluster. In many situations the network throughput increases linearly with the number of users, and the tradeoff between throughput and outage is better than in traditional base-station centric systems. Simulation results with realistic numbers of users and channel conditions show that network throughput can be increased by two orders of magnitude compared to conventional schemes.
Jets from the faintest black holes

The question whether quiescent black hole X‐ray binaries are capable of powering relativistic outflows is addressed by means of simultaneous radio/X‐ray observations of a nearby system steadily emitting X‐rays below 10−8 times the Eddington luminosity. The robust detection of a radio counterpart suggests that a synchrotron emitting outflow is being powered by this system, even though its degree of collimation remains unknown, and hard to investigate. With the inclusion of the A0620‐00 data, the non linear radio/X‐ray correlation for hard state black hole X‐ray binaries appears to hold down to very low quiescent luminosities. However, an increasing number of outliers is being found at higher luminosities, questioning the universality of such correlation, or at least its normalization.
Total synthesis of the muscarines

Abstract The total syntheses of racemic muscarine and allo -muscarine have been achieved using as a key step the stereospecific photochemical ring expansion of a cyclobutanone.
Decarboxylative Arylation of α-Amino Acids via Photoredox Catalysis: A One-Step Conversion of Biomass to Drug Pharmacophore

The direct decarboxylative arylation of α-amino acids has been achieved via visible light-mediated photoredox catalysis. This method offers rapid entry to prevalent benzylic amine architectures from an abundant biomass, specifically α-amino acid precursors. Significant substrate scope is observed with respect to both the amino acid and arene components.
Solving the Mystery of the AFRICA Dummy

Abstract Most empirical studies have reported a negative effect on growth of being an African country, even when accounting for ethnic heterogeneity. Modeling policy choices has reduced this effect in recent studies, but these have begged the question of why Africa appears adverse to developmental policies. This paper uses a cross-sectional data set to show that the governments of arbitrary postcolonial states—as are most African states—face substantial limitations to their power and are constrained in their responses, deriving greater relative power payoffs from neo-patrimonial than from developmental policies. Differing levels of state legitimacy account therefore largely for the policy choices which characterize most of Africa.
Dissecting the professional culture: insights from inside the IT “black box”

Abstract Global and multinational corporations are increasingly relying upon information systems that are developed and operated across a multicultural environment. Teams often consist of professionals who vary greatly in their cultural dimensions. These professionals follow the guidelines of the systems development life cycle (SDLC). The SDLC phases may differ in the traits necessary for their success. Thus, cultural differences may impact the success of a systems development project. This study develops a model for studying the dimensions most valuable to the SDLC. Empirical analysis then points to both the strong belief in a “professional culture” and yet to the identification of common cultural dimensions important to specific phases of the SDLC.