cssi/SciSciGPT-SciSciNet huggingface dataset:
HVEM studies of the effects of hydrogen on the deformation and fracture of AISI type 316 austenitic stainless steel

Abstract The mechanisms of hydrogen embrittlement in AISI type 316 austenitic stainless steel have been investigated by in situ straining in a high-voltage electron microscope (HVEM) equipped with an environmental cell. Hydrogen effects on strain-induced phase transformations, the generation rate and velocity of dislocation, and crack propagation rates were studied. The salient features of the fracture were similar for cracks propagating in vacuum and in hydrogen gas. In each case, e and α′ martensite formed at the crack; the e phase extended ahead of the crack while the α′ phase was restricted to high stress regions near the crack tip. The principal effect of hydrogen was to decrease the stress required for dislocation motion, for phase transformation of the austenite, and for crack propagation.
Anisotropic Distribution of SDSS Satellite Galaxies: Planar (Not Polar) Alignment

The distribution of satellite galaxies relative to isolated host galaxies in the Sloan Digital Sky Survey (SDSS) is investigated. Host-satellite systems are selected using three different methods, yielding samples of ~3300, ~1600, and ~950 satellites. In the plane of the sky, the distributions of all three samples show highly significant deviations from circular symmetry (>99.99%, >99.99%, and 99.79% confidence levels, respectively), and the degree of anisotropy is a strong function of the projected radius, rp, at which the satellites are found. For rp 100 kpc, the SDSS satellites are aligned preferentially with the major axes of the hosts. This is in stark contrast to the Holmberg effect, in which satellites are aligned with the minor axes of host galaxies. The degree of anisotropy in the distribution of the SDSS satellites decreases with rp and is consistent with an isotropic distribution at of order the 1 σ level for 250 kpc rp 500 kpc.
Optimization of enantiocontrol in cis-selective cyclopropanation reactions catalyzed by dirhodium(II) tetrakis[alkyl 2-oxaazetidine-4(S)-carboxylates]

Both intermolecular and macrocyclic intramolecular cyclopropanation reactions occur with greater selectivity for the cis-(Z)-diastereoisomer than for the trans-(E)-diastereomer in reactions catalyzed by chiral dirhodium(II) azetidinone-carboxylates; the influence of the catalyst’s ester alkyl group on enantiocontrol is substantial but appears to be delicately balanced by steric factors.
Transport properties of transition-metal-encapsulated Si cages

We performed density functional pseudopotential calculations of the spin-dependent transport through transition-metal-atom-encapsulated Si cages ${\mathrm{Si}}_{12}X$ ($X=\mathrm{Mn}$, Fe, and Co). The effect of the metal atom on conductance is studied. Mn- and Fe-doped systems show highly spin-polarized transmission whereas the magnetization in Co-doped system is quenched. It is found that electrons are transferred from Si atoms into the minority $d$ orbitals of the metal atoms. The conductance decreases as these electrons become localized around the encapsulated atoms.
1/2-Heavy Sequences Driven By Rotation

We investigate the set of $$x \in S^1$$ such that for every positive integer $$N$$ , the first $$N$$ points in the orbit of $$x$$ under rotation by irrational $$\theta $$ contain at least as many values in the interval $$[0,1/2]$$ as in the complement. By using a renormalization procedure, we show both that the Hausdorff dimension of this set is the same constant (strictly between zero and one) for almost-every $$\theta $$ , and that for every $$d \in [0,1]$$ there is a dense set of $$\theta $$ for which the Hausdorff dimension of this set is $$d$$ .
Improved methods for divisible load distribution on k-dimensional meshes using pipelined communications

We give the closed form solutions to the parallel time and speedup of the classic method for processing divisible loads on linear arrays as functions of N, the network size. We propose two methods which employ pipelined communications to distribute divisible loads on linear arrays. We derive the closed form solutions to the parallel time and speedup for both methods and show that the asymptotic speedup of both methods is /spl beta/+1, where /spl beta/ is the ratio of the time for computing a unit toad to the time for communicating a unit load. Such performance is even better than that of the known methods on k-dimensional meshes with k>1. The two new algorithms which use pipelined communications are generalized to distribute divisible loads on k-dimensional meshes, and we show that the asymptotic speedup of both algorithms is k/spl beta/+1, where k/spl ges/1. We also prove that, on k-dimensional meshes where k/spl ges/1, as the network size becomes large, the asymptotic speedup of 2k/spl beta/+1 can be achieved for processing divisible loads by using interior initial processors.
HEAP: a hierarchical energy aware protocol for routing and aggregation in sensor networks

Applications requiring monitoring such as medical and habitat monitoring, pose a great challenge to sensor network protocols. Power consumption in wireless sensor networks is largely constrained in each node of the network due to the size and the availability of the energy resources. Therefore, having an enhanced scheme that can save transmission energy is ideal. This paper presents an energy efficient and fault tolerant algorithm for routing in wireless sensor networks, which meets sensor networks requirements for monitoring systems that huge amount of events are sensed in them. The algorithm constructs a hierarchy tree over the network and maintains the distribution of energy by restructuring the hierarchy tree over time. The proposed idea was implemented using PARSEC and compared to the HPEQ protocol. Evaluations showed that the proposed algorithm is proper solution for systems with high amount of data sensed because of efficient energy distribution in the network and the ability to aggregate iterative data hierarchically.
Synthesis of 6-[18F]fluorodopamine, 6-[18F]fluoro-m-tyramine and 4-[18F]fluoro-m-tyramine+

A new method for the preparation of 6-[ 18 F]fluorodopamine (3) and [ 18 F]fluorinated analogs of m-tyramine based on a regioselective radiofluorodestannylation reaction has been developed. The radiofluorodestannylation of 6-trimethylstannyldopamine derivative 1 was carried out with [ 18 F]F 2 to give the corresponding [ 18 F]fluoro intermediate 2. Acid deprotection of 2 with 48% HBr followed by HPLC purification afforded 6-[ 18 F]fluorodopamine (3) in 18% radiochemical yield. Similarly, 6- and 4-[ 18 F]fluoro-m-tyramines (6a and 6b) were prepared from their corresponding trimethylstannyl-m-tyramine derivatives in 25 and 8% radiochemical yields, respectively. In all cases, after HPLC purification of the final products, tin concentrations were found to be <15 ppb.
Index membership and predictability of stock returns: The case of the Nikkei 225☆

Abstract When stocks are added to (deleted from) an index, more (less) information should be generated and incorporated into their prices, leading to higher (lower) pricing efficiency and lower (higher) return predictability for them. We test this hypothesis for the first time using membership changes in the Nikkei 225. Employing two alternative tests, we document that the return series become more (less) random and, thus, less (more) predictable for stocks added (deleted). We further find that these changes are related to changes in the information environment for the stocks involved, supporting the hypothesis. These findings should be of interest to portfolio managers.
Myopic loss aversion and market experience

Abstract We probe the boundaries of myopic loss aversion (MLA) theory through market treatments designed to reduce the MLA effect. Our market settings separate investment commitment from information frequency, display a running average asset value and explore the influence of participant experience. The market-based results suggest MLA persists with inexperienced participants despite efforts to mitigate MLA. Prices in markets with returning participants do not display an MLA effect. However, the same experienced participants individually succumb to MLA in an allocation setting immediately following the market. Overall, our results suggest that, while market experience mitigates the MLA effect, participants do not transfer these results to other settings.
Hydrodenitrogenation of Quinoline over High-Surface-Area Mo2N

Abstract The reaction pathway far the hydrodenitrogenation of quinoline over Mo 2 N has been investigated. Quinoline is found to undergo a rapid hydrogenation to form 1,2,3,4,-tetrahydroquinoline. This product then reacts more slowly to form 2-propylaniline, which, in turn, undergoes hydrogenolysis of the CN bond in the saturated ring to farm propylbenzene. No evidence is found for propylcyclohexane.
HIGH RESOLUTION RADIO AND OPTICAL OBSERVATIONS OF THE CENTRAL STARBURST IN THE LOW-METALLICITY DWARF GALAXY II Zw 40

The extent to which star formation varies in galaxies with low masses, low metallicities, and high star formation rate surface densities is not well constrained. To gain insight into star formation under these physical conditions, this paper estimates the ionizing photon fluxes, masses, and ages for young massive clusters in the central region of II Zw 40—the prototypical low-metallicity dwarf starburst galaxy—from radio continuum and optical observations. Discrete, cluster-sized sources only account for half the total radio continuum emission; the remainder is diffuse. The young ( 5 Myr) central burst has a star formation rate surface density that significantly exceeds that of the Milky Way. Three of the 13 sources have ionizing photon fluxes (and thus masses) greater than R136 in 30 Doradus. Although isolating the effects of galaxy mass and metallicity is difficult, the H II region luminosity function and the internal extinction in the center of II Zw 40 appear to be primarily driven by a merger-related starburst. The relatively flat H II region luminosity function may be the result of an increase in interstellar medium pressure during the merger and the internal extinction is similar to that generated by the clumpy and porous dust in other starburst galaxies.
Galaxy clusters: oblate or prolate?

ABSTRA C T It is now well known that a combined analysis of the Sunyaev‐Zel’dovich (SZ) effect and the X-ray emission observations can be used to determine the angular diameter distance to galaxy clusters, from which the Hubble constant is derived. Given that the SZ/X-ray Hubble constant is determined through a geometrical description of clusters, the accuracy to which such distance measurements can be made depends on how well one can describe intrinsic cluster shapes. Using the observed X-ray isophotal axial ratio distribution for a sample of galaxy clusters, we discuss intrinsic cluster shapes and, in particular, if clusters can be described by axisymmetric models, such as oblate and prolate ellipsoids. These models are currently favoured when determining the SZ/X-ray Hubble constant. We show that the current observational data on the asphericity of galaxy clusters suggest that clusters are more consistent with a prolate than with an oblate distribution. We address the possibility that clusters are intrinsically triaxial by viewing triaxial ellipsoids at random angles with the intrinsic axial ratios following an isotropic Gaussian distribution. We discuss implications of our results on current attempts at measuring the Hubble constant using galaxy clusters and suggest that an unbiased estimate of the Hubble constant, not fundamentally limited by projection effects, would eventually be possible with the SZ/X-ray method.
Intensification of North American Megadroughts through Surface and Dust Aerosol Forcing

Tree-ring-based reconstructions of the Palmer drought severity index (PDSI) indicate that, during the Medieval Climate Anomaly (MCA), the central plains of North America experienced recurrent periods of drought spanning decades or longer. These megadroughts had exceptional persistence compared to more recent events, but the causes remain uncertain. The authors conducted a suite of general circulation model experiments to test the impact of sea surface temperature (SST) and land surface forcing on the MCA megadroughts over the central plains. The land surface forcing is represented as a set of dune mobilization boundary conditions, derived from available geomorphological evidence and modeled as increased bare soil area and a dust aerosol source (32deg-44degN, 105deg-95degW). In the experiments, cold tropical Pacific SST forcing suppresses precipitation over the central plains but cannot reproduce the overall drying or persistence seen in the PDSI reconstruction. Droughts in the scenario with dust aerosols, however, are amplified and have significantly longer persistence than in other model experiments, more closely matching the reconstructed PDSI. This additional drying occurs because the dust increases the shortwave planetary albedo, reducing energy inputs to the surface and boundary layer. The energy deficit increases atmospheric stability, inhibiting convection and reducing cloud cover and precipitation over the central plains. Results from this study provide the first model-based evidence that dust aerosol forcing and land surface changes could have contributed to the intensity and persistence of the central plains megadroughts, although uncertainties remain in the formulation of the boundary conditions and the future importance of these feedbacks.
The BTeV trigger system

Abstract BTeV is a dedicated beauty and charm experiment proposed for the Fermilab Tevatron. The broad physics program envisaged for BTeV requires a trigger that is efficient for a wide variety of heavy-quark decays, including those to all-hadronic final states. To achieve this, we plan to trigger on evidence of detached vertices at the very first trigger level, taking advantage of fast-readout pixel detectors to facilitate fast pattern recognition. Simulations show that 100-to-1 rejection of light-quark background events can be achieved at Level 1 using specialized trackfinding hardware, and that an additional factor of 10–100 in data reduction can be achieved using general purpose processor farms at Levels 2 and 3. This is adequate to allow data taking at luminosities in excess of 2×10 32 cm −2 s −1 .
Investments in flexible production capacity

Abstract We examine the technology and capacity choice problem of a multi-output firm facing stochastic demands in a continuous-time framework. The firm can install output-specific capital, or, at greater cost, flexible capital that can be used to produce different outputs. Investment is irreversible. The firm must choose a technology and decide how much capital to install, knowing it can add more later as demand evolves. We formulate the capacity choice problem as a singular stochastic control problem, show that the value of the firm equals the value of its installed capital plus the value of its options to add capacity in the future, and derive an optimal investment rule that maximizes the firm's market value. We also address the analogous problem for a multi-input firm that faces stochastically evolving factor costs, and can install input-specific or flexible capital.
Catalysis for fluorination and trifluoromethylation

Recent advances in catalysis have made the incorporation of fluorine into complex organic molecules easier than ever before, but selective, general and practical fluorination reactions remain sought after. Fluorination of molecules often imparts desirable properties, such as metabolic and thermal stability, and fluorinated molecules are therefore frequently used as pharmaceuticals or materials. But the formation of carbon-fluorine bonds in complex molecules is a significant challenge. Here we discuss reactions to make organofluorides that have emerged within the past few years and which exemplify how to overcome some of the intricate challenges associated with fluorination.
Mechanical properties of crosslinks controls failure mechanism of hierarchical intermediate filament networks

Intermediate filaments are one of the key components of the cytoskeleton in eukaryotic cells, and their mechanical properties are found to be equally important for physiological function and disease. While the mechanical properties of single full length filaments have been studied, how the mechanical properties of crosslinks affect the mechanical property of the intermediate filament network is not well understood. This paper applies a mesoscopic model of the intermediate network with varied crosslink strengths to investigate its failure mechanism under the extreme mechanical loading. It finds that relatively weaker crosslinks lead to a more flaw tolerant intermediate filament network that is also 23% stronger than the one with strong crosslinks. These findings suggest that the mechanical properties of interfacial components are critical for bioinspired designs which provide intriguing mechanical properties.
Fixed-trim re-entry guidance analysis

The terminal guidance problem for a fixed-trim re-entry body is formulated with the objective of synthesizing a closed-loop steering law. A transformation of variables and subsequent linearization of the motion, with the sight-line to the target as a reference, reduces the order of the state system for the guidance problem. The reduced order system, although nonlinear and time-varying, is simple enough to lend itself to synthesis of a class of guidance laws. A generalization of the feedforward device of classical control theory is successfully employed for compensation of roll autopilot lags. The proposed steering law exhibits superior miss-distance performance in a computational comparison with existing fixed-trim guidance laws.
Online Markov Decision Processes With Kullback–Leibler Control Cost

This paper considers an online (real-time) control problem that involves an agent performing a discrete-time random walk over a finite state space. The agent's action at each time step is to specify the probability distribution for the next state given the current state. Following the setup of Todorov, the state-action cost at each time step is a sum of a state cost and a control cost given by the Kullback–Leibler (KL) divergence between the agent's next-state distribution and that determined by some fixed passive dynamics. The online aspect of the problem is due to the fact that the state cost functions are generated by a dynamic environment, and the agent learns the current state cost only after selecting an action. An explicit construction of a computationally efficient strategy with small regret (i.e., expected difference between its actual total cost and the smallest cost attainable using noncausal knowledge of the state costs) under mild regularity conditions is presented, along with a demonstration of the performance of the proposed strategy on a simulated target tracking problem. A number of new results on Markov decision processes with KL control cost are also obtained.
On the Specification of Propensity Scores: with Applications to the Analysis of Trade Policies

The use of propensity score methods for program evaluation with nonexperimental data typically requires that the propensity score be estimated, often with a model whose specification is unknown. Although theoretical results suggest that estimators using more flexible propensity score specifications perform better, this has not filtered into applied research. Here we provide Monte Carlo evidence indicating benefits of overspecifying the propensity score that are robust across a number of different covariate structures and estimators. We illustrate these results with two applications, one assessing the environmental effects of General Agreement on Tariffs and Trade/World Trade Organization membership and the other assessing the impact of adopting the euro on bilateral trade.
Discovery of Inverse-Compton X-Rays in Radio Lobes

Inverse-Compton (IC) scattering of cosmic microwave background photons into the X-ray band by relativistic electrons in diffuse radio lobes is an obligatory process. We present the strongest evidence to date for the detection of these IC X-rays. They appear in a deep image of the nearby radio galaxy Fornax A (=NGC 1316) obtained with the Position Sensitive Proportional Counter on board the ROSAT satellite. The spatial correspondence of the X-ray and radio emission is excellent. The absence of Faraday depolarization in the lobes argues strongly against the possibility that the X-rays are due to an entrained thermal plasma. The detected level of X-rays is somewhat higher than, but consistent with, that expected from the assumption of equipartition between magnetic fields and relativistic electrons in the lobes. This observation provides the first direct estimate of the magnetic field of a radio lobe, BIC 2-3 μG, indicating that the integrated energy output of this active galactic nucleus is near the minimum energy level.
The Double and Dual of a Quasitriangular Lie Bialgebra

Let G be a connected, simply connected Poisson-Lie group with quasitriangular Lie bialgebra g. An explicit description of the double D(g) is given, together with the embeddings of g and g^*. This description is then used to provide a construction of the double D(G). The aim of this work is to describe D(G) in sufficient detail to be able to apply the procedures of Semenov-Tian-Shansky and Drinfeld for the classification of symplectic leaves and Poisson homogeneous spaces for Poisson-Lie groups.
Lattice Charge Overlap I. Elastic Limit of Pi and Rho Mesons

Using lattice quantum chromodynamics on a 163×24 lattice atβ=6.0, we examine the elastic limit of charge overlap functions in the quenched approximation for the pion and rho mesons; results are compared to previous direct current insertion calculations. A good signal is seen for the pion, but the electric and magnetic rho meson results are considerably noisier. We find that the pion and rho results are characterized by a monopole mass to rho mass ratio of 0.97(8) and 0.73(10), respectively. Assuming that the functional forms of the electric and magnetic form factors are the same, we also find a rho mesong-factor ofg=2.25(34), consistent with the nonrelativistic quark model.
Energy transfer in ordered and unordered photochemical systems.

BS>A qualitative discussion is presented of the theoretical mental criteria of this phenomenon and, finally, with its possible role in primary quantum conversion in photosynthesis. (W.L.H.)
Microwave spectrum and 14N quadrupole coupling constants of indole

Abstract The microwave spectrum of indole has been observed using a conventional Stark-modulated microwave spectrometer in conjunction with a heated absorption cell. Spectral transitions were also observed in a pulsed molecular beam Fabry-Perot microwave spectrometer using a heated nozzle source. The high resolution (20 kHz) available with the Fabry-Perot instrument allows the observation of the 14N nuclear electric quadrupole hyperfine splittings. An analysis of the 44 measured transitions gives the following rotational constants: A = 3877.8366(64) MHz; B = 1636.0461(48) MHz; and C = 1150.0900(19) MHz. The 14N quadrupole coupling constants that were determined from the hyperfine analysis are eQqaa = 1.7263(43) MHz; eQqbb = 1.6525(50) MHz; and eQqcc = −3.3788(48) MHz. The observed rotational constants are compared with those obtained from a recent optical study of indole and the 14N quadrupole coupling constants are compared with those of pyrrole.
Partitions of difference sets and code synchronization

Difference systems of sets (DSS) are combinatorial structures that are a generalization of cyclic difference sets and arise in connection with code synchronization. The paper surveys recent constructions and open problems concerning DSS obtained as partitions of cyclic difference sets.
Photoplus: auxiliary information for printed images based on distributed source coding

A printed photograph is difficult to reuse because the digital information that generated the print may no longer be available. This paper describes a mechanism for approximating the original digital image by combining a scan of the printed photograph with small amounts of digital auxiliary information kept together with the print. The auxiliary information consists of a small amount of digital data to enable accurate registration and color-reproduction, followed by a larger amount of digital data to recover residual errors and lost frequencies by distributed Wyner-Ziv coding techniques. Approximating the original digital image enables many uses, including making good quality reprints from the original print, even when they are faded many years later. In essence, the print itself becomes the currency for archiving and repurposing digital images, without requiring computer infrastructure.
Techniques for Deep Sea Near Bottom Survey Using an Autonomous Underwater Vehicle

This paper reports the development and at-sea deployment of a set of algorithms that have enabled the autonomous underwater vehicle ABE to conduct near-bottom surveys in the deep sea. Algorithms for long baseline acoustic positioning, terrain-following, and automated nested surveys are reported.
The Order of Curvature Operators on Loop Groups

For loop groups (free and based), we compute the exact order of the curvature operator of the Levi-Civita connection depending on a Sobolev space parameter. This extends results of Freed (J Differ Geom 28:223–276, 1988) and Maeda et al. (Riemannian geometry on loop spaces. arXiv:0705.1008v3, 2008).
Riemannian metrics on locally projectively flat manifolds

The expression [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="01i" /] transforms as a symmetric (0, 2) tensor under projective coordinate changes of a domain in R n so long as u transforms as a section of a certain line bundle. On a locally projectively flat manifold, the section u can be regarded as a metric potential analogous to the local potential in Kahlergeometry. Let M be a compact locally projectively flat manifold. We prove that if u is a negative section of the dual of the tautological bundle such that [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="02i" /] is a Riemannian metric, then M is projectively equivalent to a quotient of a bounded convex domain in R n . The same is true for such manifolds M with boundary if u = 0 on the boundary. This theorem is an analog of a result of Schoen and Yau in locally conformally flat geometry. The proof involves affine differential geometry techniques developed by Cheng and Yau.
Certifying the Restricted Isometry Property is Hard

This paper is concerned with an important matrix condition in compressed sensing known as the restricted isometry property (RIP). We demonstrate that testing whether a matrix satisfies RIP is NP-hard. As a consequence of our result, it is impossible to efficiently test for RIP provided P ≠ NP.
Nash solution and uncertain disagreement points

Abstract We analyze bargaining problems with known feasible sets but uncertain disagreement points. We investigate the existence of solutions such that, under reasonably restricted circumstances, all agents be as well off by reaching an agreement today as they would be by waiting until the uncertainty is resolved. We use this requirement, together with a few other commonly used conditions, to characterize the Nash solution.
Recognizing Materials Using Perceptually Inspired Features

Our world consists not only of objects and scenes but also of materials of various kinds. Being able to recognize the materials that surround us (e.g., plastic, glass, concrete) is important for humans as well as for computer vision systems. Unfortunately, materials have received little attention in the visual recognition literature, and very few computer vision systems have been designed specifically to recognize materials. In this paper, we present a system for recognizing material categories from single images. We propose a set of low and mid-level image features that are based on studies of human material recognition, and we combine these features using an SVM classifier. Our system outperforms a state-of-the-art system (Varma and Zisserman, TPAMI 31(11):2032–2047, 2009) on a challenging database of real-world material categories (Sharan et al., J Vis 9(8):784–784a, 2009). When the performance of our system is compared directly to that of human observers, humans outperform our system quite easily. However, when we account for the local nature of our image features and the surface properties they measure (e.g., color, texture, local shape), our system rivals human performance. We suggest that future progress in material recognition will come from: (1) a deeper understanding of the role of non-local surface properties (e.g., extended highlights, object identity); and (2) efforts to model such non-local surface properties in images.
Charges of monopole operators in Chern-Simons Yang-Mills theory

We calculate the non-abelian R-charges of BPS monopole operators in three-dimensional gauge theories with \( \mathcal{N} = 3 \) supersymmetry. This class of models includes ABJM theory, the proposed gauge theory dual of M-theory on \( {{Ad{S_4} \times {S^7}} \mathord{\left/{\vphantom {{Ad{S_4} \times {S^7}} {{\mathbb{Z}_k}}}} \right.} {{\mathbb{Z}_k}}} \). In the UV limit of the \( \mathcal{N} = 3 \) theories the Yang-Mills coupling becomes weak and the monopole operators are described by classical backgrounds. This allows us to find their SU(2)R charges in a one-loop computation which by virtue of the non-renormalization of non-abelian R-charges yields the exact result for any value of the coupling. The spectrum of SU(2)R charges is found by quantizing the SU(2)/U(1) collective coordinate of the BPS background, whose dynamics is that of a charged particle on a sphere with a Wess-Zumino term representing a magnetic monopole at its center. If the Wess-Zumino coefficient is h, then the smallest possible SU(2)R representation for BPS monopole operators has spin |h|/2. We find, in agreement with earlier proposals, that h is proportional to the sum of the U(1)R charges of all the fermion fields weighted by the effective monopole charges determined by their gauge representations. The field content of ABJM theory is such that h = 0. This proves for any Chern-Simons level k the existence of monopole operators which are singlets under all global symmetries and have vanishing scaling dimensions. These operators are essential for matching the spectrum of the ABJM theory with supergravity and for the supersymmetry enhancement to \( \mathcal{N} = 8 \).
MATERNAL VARICELLA INFECTION AS A CAUSE OF FETAL MALFORMATIONS

Abstract An infant with multiple congenital Summary anomalies which demonstrated the teratogenic potential of maternal varicella infection in early pregnancy is described. The varicella-zoster virus must be included with rubella as an infectious agent capable of producing fetal malformations.
The Installation, Testing, and Lessons Learned of the TF40B Gas Turbine Test Facility

The TF40B Gas Turbine Test Facility is the only dedicated Landing Craft, Air Cushion main propulsion engine test complex available to the U.S. Navy. This facility, located at the Naval Surface Warfare Center, Carderock Division (NSWCCD) in Philadelphia, PA, began operation in August, 1992. Since then, the test engine has logged approximately 230 starts and 350 operating hours. This paper will present the installation, testing, and lessons learned of the TF40B test facility. The installation section will discuss the modifications made to the existing test facility to accept the TF40B engine. The test section will include the Foreign Object Damage (FOD) screen evaluation, both on-line and crank wash detergent fluid evaluations, cold weather fuel testing, engine vent line testing and Aerojet 5 oil evaluation. The lessons learned section will include problems related to the electric starter, waterbrake, inlet and exhaust systems, data acquisition system, instrumentation control panel, and the test cell equipment arrangement.
Global Precipitation Measurement mission - architecture and mission concept

The Global Precipitation Measurement (GPM) mission is a collaboration between the National Aeronautics and Space Administration (NASA) and the Japanese Aerospace Exploration Agency (JAXA), and other US and international partners, with the goal of monitoring the diurnal and seasonal variations in precipitation over the surface of the Earth. These measurements will be used to improve current climate models and weather forecasting, and enable improved storm and flood warnings. This paper gives an overview of the mission architecture and addresses some of the key trades that have been completed, including the selection of the Core Observatory's orbit, orbit maintenance trades, and design issues related to meeting orbital debris requirements.
Logspace hierarchies, polynomial time and the complexity of fairness problems concerning Ω-machines

In this paper, we define a restricted logspace oracle hierarchy which turns out to be equivalent to the logspace alternation hierarchy (of Chandra, Kozen and Stockmeyer) and thus is contained within the second level of the logspace oracle heirarchy (of Ruzzo, Simon and Tompa). We then examine problems concerning various types of “fair” computations with respect to $\omega $-Finite State Machines ($\omega $-FSM’s) and $\omega $-One Counter Machines ($\omega $-1CM’s). For example, we consider the nonemptiness problem for $\omega $-FSM’s and $\omega $-1CM’s where acceptance is defined in the usual fashion, but with a fairness constraint imposed on accepting computations. Our results yield problems that are complete not only for LOGSPACE and PTIME but the second and third levels of the restricted logspace oracle hierarchy as well. As far as we know, these are the first natural problems shown to be complete for various levels of the logspace alternation hierarchy. The problems are also of independent interest....
Iterative inverse scattering method employing Gram-Schmidt orthogonalization

Abstract An inverse scattering method is tested which appears to work very well. It is an iterative procedure based on the distorted wave Born approximation. The resulting Fredholm equation of the first kind is solved by a projection method that requires the construction of an orthonormal set of basis functions from the set of kernel functions. This can be done by the spectral expansion method which entails matrix diagonalization or by Gram-Schmidt orthogonalization. The method is tested on a simple one-dimensional optical wave inverse scattering problem. Both orthonormalization methods lead to a rapidly convergent and stable iteration. The spectral expansion method gives somewhat better results, but the Gram-Schmidt orthogonalization method, which is the novel aspect of our approach, is much less time-consuming. We show how the projection method can be generalized to the case of acoustic wave scattering where the target must be characterized by more than a single independent function of position.
Active structural acoustic control of noise transmission through double panel systems

A preliminary parametric study of active control of sound transmission through double panel systems has been experimentally performed. The technique used is the active structural acoustic control (ASAC) approach where control inputs, in the form of piezoelectric actuators, were applied to the structure while the radiated pressure field was minimized. Results indicate the application of control inputs to the radiating panel resulted in greater transmission loss due to its direct effect on the nature of the structural-acoustic coupling between the radiating panel and the receiving chamber. Increased control performance was seen in a double panel system consisting of a stiffer radiating panel with a lower modal density. As expected, more effective control of a radiating panel excited on-resonance is achieved over one excited off-resonance. In general, the results validate the ASAC approach for double panel systems and demonstrate that it is possible to take advantage of double panel behavior to enhance control performance, although it is clear that further research must be done to understand the physics involved
How Common Are Magnetars? The Consequences of Magnetic Field Decay

Ultramagnetized neutron stars, or magnetars, have been invoked to explain several astrophysical phenomena. We examine how the magnetic field of a magnetar will decay over time and how this decay affects the cooling of the object. We find that for sufficiently strong nascent fields, field decay alters significantly the cooling evolution relative to similarly magnetized neutron stars with constant fields. As a result, old magnetars can be expected to be bright in the soft X-ray band. The soft X-ray source RX J0720.4-3125 may well be the nearest such old magnetar.
Enabling shared audit data

Audit is an important aspect of good security and business practice; however, current solutions are not supportive of electronic data and processes. This paper describes an audit service that both acts as a central place for logging from heterogeneous IT systems and a place to search and check the audit data. Notarisation structures enabling a user to check the integrity of audit records and subsets of the audit chain relating to their transactions have been developed. The audit system uses a secure hardware device to create an alternative trust domain in which to run processes, maintaining the integrity of the audit trail whilst allowing it to be tightly integration and co-located with the overall IT infrastructure.
Interspecies and interkingdom communication mediated by bacterial quorum sensing.

Quorum sensing (QS) has traditionally referred to a mechanism of communication within a species of bacteria. However, emerging research implicates QS in interspecies communication and competition, and such systems have been proposed in a wide variety of bacteria. This activity of bacterial QS also extends to relationships between bacteria and eukaryotes and host–pathogen interactions in both clinical and agricultural settings are of particular interest. These relationships are particularly pertinent in light of the rising prevalence of antibiotic resistant bacteria. In this tutorial review we describe bacterial QS and its capacity in interspecies and interkingdom interactions, as well as the corresponding eukaryotic responses.
How Lumpy Is the Milky Way's Dark Matter Halo?

Cold dark matter (CDM) simulations predict that there are hundreds of lumps with masses greater than 107 M☉ in the Milky Way halo. However, we know of only a dozen dwarf satellites close to this mass. Are these lumps simply lacking in stars, or is there a fundamental flaw in our most popular cosmology? By studying the tidal debris of known satellites, we can potentially address this question. In this paper, we quantify the effects of the dark matter lumps on tidal tails. The lumps scatter stars in the tidal tails from their original orbits, producing a distinctive signature. We simulate debris evolution in smooth and lumpy halo potentials, and use our simulations to motivate and test a statistical measure of the degree of scattering apparent in the angular position and radial velocity measurement of debris stars—the "scattering index." We find that the scattering index can in general distinguish between the levels of substructure predicted by CDM cosmologies and smooth Milky Way models, but the sensitivity of the debris depends on the orientation of the parent satellite's orbit relative to the largest lumps' orbits. We apply our results to the carbon star stream associated with the Sagittarius dwarf galaxy (Sgr), and find that these stars appear to be more scattered than we expect for debris orbiting in a smooth halo. However, the degree of scattering is entirely consistent with that expected because of the influence of the Large Magellanic Cloud, which is on an orbit that intersects Sgr's own. We conclude that the current data are unable to constrain CDM models. Nevertheless, our study suggests that future data sets of debris stars associated with other Milky Way satellites could provide strong constraints on CDM models.
The Ultrasound-Promoted Aluminum Amalgam Reduction of Phthalimides to Hydroxy Lactams

Abstract A new method for the reduction of N-substituted phthalimides to the corresponding hydroxy lactams is described which utilizes aluminum amalgam and is promoted by high-intensity ultrasound. The ultrasonic irradiation serves to rapidly fragment the amalgam creating a reactive dispersion as well as increasing mass transport between solution and surface thereby accelerating the reaction rate. While the yields of hydrbxy lactams derived from the corresponding phthalimides are in the range of 69–94%, both N-benzyl glutarimide and N-benzyl succinimide are not reduced. The reduction does not affect the double bond or ester function of a representative α,β-enoate ester.
Solar energy, its conversion and utilization

This paper discusses the part solar energy, our only energy income, can play in meeting our ever increasing energy demands. The basic characteristics of solar energy and the solar properties of materials are mentioned. The conversion of solar energy to the forms of energy which are needed in our daily life are explained.
OH rotational temperature from two-line laser-excited fluorescence

A two-line laser-excited fluorescence technique has been developed to measure the rotational temperature of the OH molecule. This technique eliminates problems encountered in the application of other laser fluorescence methods for measuring the OH temperature in combustion environments, such as fluorescence trapping, nonequilibrium excited state population, spectral bandwidth sensitivity, and quenching. The technique consists of exciting a specific rotational level of the OH molecule in the A(2)Sigma (upsilon' = 0) excited state from two different rotational levels in the X(2)Pi(upsilon'' = 0) ground state using a tunable dye laser and monitoring the broadband fluorescence. An example of the implementation of this technique in an atmospheric pressure methane-air flat flame is included. The possible application of this technique in turbulent combustion is also evaluated.
Sequential estimation of observation error variances in a trajectoryestimation problem.

Sequential trajectory estimation improved by implementing simple running estimates of observation error variances
Influence of Icing Information on Pilot Strategies for Operating in Icing Conditions

Theine uenceofpotential remoteice-detectionsystem featuresonpilotdecision makingwasinvestigated through a Web-based experiment. Display features including a graphical plan view depiction of icing severity, vertical view depiction, single and multiple icing severity levels as well as sensor range were varied in a part-task simulation experiment. Using information from each display, pilots were presented with a set of four e ight scenarios and probed on theirrouting decisions and comfort level with thosedecisions. Theexperimentalso included a subjective display preference evaluation. Results show that all of the displays improved pilot decision making over existing text-based icing information. The three-dimensional displays that included vertical depiction of icing conditions were found to support improved decision making. Range was not found to be a strong factor in the experiment; however, the minimum range tested was 25 n miles, which may be in excess of current technical capabilities. The depictionoftheseverity oficingconditionswasnotfoundto beasimportantasaccurateinformation on thelocation of icing conditions.
Polyunsaturated posets and graphs and the Greene-Kleitman theorem

A partition of a finite poset into chains places a natural upper bound on the size of a union of k antichains. A chain partition is k-saturated if this bound is achieved. Greene and Kleitman (J. Combin. Theory Ser. A 20 (1976) 41) proved that, for each k, every finite poset has a simultaneously k- and k + 1-saturated chain partition. West (J. Combin. Theory Ser. A 41 (1986) 105) showed that the Greene-Kleitman Theorem is best possible in a strong sense by exhibiting, for each c ≥ 4, a poset with longest chain of cardinality c and no k- and l-saturated chain partition for any distinct, nonconsecutive k, l > c. We call such posets polyunsaturated. We give necessary and sufficient conditions for the existence of polyunsaturated posets with prescribed height, width, and cardinality. We prove these results in the more general context of graphs satisfying an analogue of the Greene-Kleitman Theorem. Lastly, we discuss analogous results for antichain partitions.
Branes probing black holes

Abstract We consider a brane moing close to a large number of coincident branes. We compare the calculation of the effective action using the gauge theory living on the brane and the calculation using the supergravity approximation. We discuss some general features about the correspondence between large N gauge theories and black holes. Then we do a one loop calculation which applies for extremal and near extremal black holes. We comment on the expected results for higher loop calculations. We make some comments on the Matrix theory interpretation of these results.
Competition in the Promised Land: Black Migration and Racial Wage Convergence in the North, 1940–1970

Author(s): Boustan, Leah | Abstract: In the mid-twentieth century, relative black wage growth in the North lagged behind the Jim Crow South. Inter-regional migration may explain this trend. Four million black southerners moved North from 1940 to 1970, more than doubling the northern black population. Black migrants will exert more competitive pressure on black wages if blacks and whites are imperfect substitutes. I use variation in the relative black-white migrant flows across skill groups to estimate the elasticity of substitution by race in the northern economy. I then calculate a counterfactual rate of black-white wage convergence in the North in the absence of southern migration. Migration slowed the pace of northern convergence by 50 percent, more than accounting for the regional gap. Ongoing migration appears to have been an impediment to black economic assimilation in the urban North.
On Union Ultrafilters

We present some new results on union ultrafilters. We characterize stability for union ultrafilters and, as the main result, we construct a new kind of unordered union ultrafilter.
The Lockean Constitution: Separation of Powers and the Limits of Prerogative

In the post-9/11 era, many legal scholars have advanced theories of constitutional law that make allowance for unreviewable discretionary decision making by the executive branch, particularly in the context of the “war on terror”. Drawing on Lockean constitutional theory for normative support, the author develops an alternative constitutional model that addresses the problem of discretionary executive power. Locke’s constitution divides political power between the executive and the legislature, with the latter checking and balancing the former. Both the executive and the legislature have a fiduciary trust to act for the public good. Locke closely links the public good and the constitution such that any breach of the constitution is per se a breach of the public good. Therefore, unreviewable decision making by the executive always violates its trust because it is a breach of the constitution. After setting out Locke’s theory of separation of powers, the author presents a modified model that makes the judiciary, in addition to the legislature, responsible for the accountability of executive decision makers. Although the executive retains its prerogative power, it must always remain accountable to the legislature and the courts, even in emergencies.