cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal unsharp mask for image sharpening and noise removal

We consider the problem of restoring a noisy blurred image using an adaptive unsharp mask filter. Starting with a set of very high quality images, we use models for both the blur and the noise to generate a set of degraded images. With these image pairs, we optimally train the strength parameter of the unsharp mask to smooth flat areas of the image and to sharpen areas with detail. We characterize the blur and the noise for a specific hybrid analog/digital imaging system in which the original image is captured on film with a low-cost analog camera. A silver-halide print is made from this negative; and this is scanned to obtain a digital image. Our experimental results for this imaging system demonstrate the superiority of our optimal unsharp mask compared to a conventional unsharp mask with fixed strength.
Transport theory for light propagation in random media

We review the theory of the radiative transport equation governing the radiance in a random medium. Using symmetry and orthogonal properties of plane wave solutions, we can compute readily the Green's function for a uniform medium. We use this Green's function to develop a general theory for inhomogeneous media analogous to scattering theory for classical wave propagation.
STRUCTURAL CLASSIFICATION AND GENERAL PRINCIPLES FOR THE DESIGN OF SPHERICAL MOLECULAR HOSTS

Cryptands, carcerands, polyoxometalates, and molecular capsules are cagelike hosts that complex guests through encapsulation. Following the discovery of a nanometer scale supramolecular shell-like spheroid, these and other shell-like hosts were structurally classified. Their frameworks may be catalogued according to principles of solid geometry. This has led to the identification of hosts that have not yet been synthesized or discovered (such as the cuboctahedron shown; X=O, S) and should lead to the design of additional container assemblies.
Dimensionally reduced Landau-Ginzburg orbifolds with discrete torsion

Abstract It is observed that a large class of (2,2) string vacua with n =5 superfields can be rewritten as Landau-Ginzburg orbifolds with discrete torsion and n =5. The naive geometric interpretation (if one exists) would be that of a complex three-fold, not necessarily Kahler but still with vanishing first Chern class.
Black hole entropy, marginal stability and mirror symmetry

We consider the superconformal quantum mechanics associated to BPS black holes in type IIB Calabi-Yau compactifications. This quantum mechanics describes the dynamics of D-branes in the near-horizon attractor geometry of the black hole. In many cases, the black hole entropy can be found by counting the number of chiral primaries in this quantum mechanics. Both the attractor mechanism and notions of marginal stability play important roles in generating the large number of microstates required to explain this entropy. We compute the microscopic entropy explicitly in a few different cases, where the theory reduces to quantum mechanics on the moduli space of special Lagrangians. Under certain assumptions, the problem may be solved by implementing mirror symmetry as three T-dualities: this is essentially the mirror of a calculation by Gaiotto, Strominger and Yin. In some simple cases, the calculation may be done in greater generality without resorting to conjectures about mirror symmetry. For example, the K3 × T2 case may be studied precisely using the Fourier-Mukai transform.
Information Technology and Diversification: How Their Relationship Affects Firm Performance

While the importance of IT coupled with organizational changes for business performance has been widely discussed in the information systems (IS) literature, there has been little empirical research on the issue. This research examines empirically the relationship between IT and diversification by employing multiple diversification measures. It also examines empirically the relative impact on performance of IT and diversification. Results show that diversification coupled with increased IT spending improves firm performance when its strategic emphasis is on related diversification. The results also show that firms place strategic focus on related diversification when they increase IT spending, and that they require more IT when their strategic emphasis is tilted toward related diversification. The findings imply that by providing a better means of coordination, IT enables scope economies, efficient utilization of business resources and collaboration across individual business units, eventually leveraging the benefits of diversification.
Broadband quasi-periodic radio and X-ray pulsations in a solar flare

We describe microwave and hard X-ray observations of strong quasi-periodic pulsations from the GOES X1.3 solar flare on 2003 June 15. The radio observations were made jointly by the Owens Valley Solar Array (OVSA), the Nobeyama Polarimeter (NoRP), and the Nobeyama Radioheliograph (NoRH). Hard X-ray observations were made by RHESSI. Using Fourier analysis, we study the frequency- and energy-dependent oscillation periods, differential phase, and modulation amplitudes of the radio and X-ray pulsations. Focusing on the more complete radio observations, we also examine the modulation of the degree of circular polarization and of the radio spectral index. The observed properties of the oscillations are compared with those derived from two simple models for the radio emission. In particular, we explicitly fit the observed modulation amplitude data to the two competing models. The first model considers the effects of MHD oscillations on the radio emission. The second model considers the quasi-periodic injection of fast electrons. We demonstrate that quasi-periodic acceleration and injection of fast electrons is the more likely cause of the quasi-periodic oscillations observed in the radio and hard X-ray emission, which has important implications for particle acceleration and transport in the flaring sources.
ABSORPTION CHANGES IN BACTERIAL CHROMATOPHORES. II. A NEW CHLOROPHYLL-LIKE PIGMENT FROM THE OXIDATION OF CHROMATOPHORES FROM RHODOSPIRILLUM RUBRUM

Evidence is presented which points to (at least) two bound forms of bacteriochlorophyll present in chromatophores of Rhodospirillum rubrum, both of them readily converted to unbound bacteriochlorophyll (abs. max. 770 mu) when the chromatophores are extracted with acetone or ethanol. Controlled oxidation of the chromatophores with Ir(IV) or with Zn(II) and ferricyanide preferentially destroys the more strongly absorbing pigment (abs. max. 880 mu) but brings about only a slight decrease in the magnitude of the photoinduced absorption changes at 810 and 792 mu. Such oxidations yield a new pigment, absorbing at 715 mu in the aqueous preparation and, more strongly, at 680-684 mu when the pigment is extracted into organic solvents. This pigment is formed irreversibly and is therefore different from the material formed by photooxidation of chromatophores. Its visible spectrum and the spectrum of the material formed from it by acidification suggest that it is a chlorophyll-like substance, possibly derived from bacteriochlorophyll by (two-electron) oxidation of one of the dihydropyrrole rings to a pyrrole ring. Directions are given for separation of this pigment from other colored compounds present in the oxidation mixtures.
Who Holds the Balance? A Missing Detail in the Debate over Balancing Security and Liberty

The question of how best to balance the pursuit of security with the protection of civil liberties has been heavily debated in recent years. This paper challenges the conclusions reached in that debate. It argues that although theorists have identified important subsidiary causes of imbalance, they do not address the structural dilemma posed by state secrecy, which creates an information asymmetry that allows officials to manipulate safeguards meant to secure an appropriate balance. Since this asymmetry cannot be easily resolved, imbalance remains a perennial danger that often can be addressed only retrospectively. Unfortunately, retrospection too can be stymied by the executive's control over state secrets, and it can also be undermined by partisanship, even when the relevant information becomes available. With this in mind, the paper identifies mechanisms to limit the abuse of state secrecy and indicates institutional features that may temper the adverse effects of partisanship.
THE QUANTUM TEICHMÜLLER SPACE AS A NONCOMMUTATIVE ALGEBRAIC OBJECT

We consider the quantum Teichmuller space of the punctured surface introduced by Chekhov–Fock–Kashaev, and formalize it as a noncommutative deformation of the space of algebraic functions on the Teichmuller space of the surface. In order to apply it in 3-dimensional topology, we put more attention to the details involving small surfaces.
Large Angle-of-Attack Missile Control Concepts for Aerodynamically Controlled Missiles

A coupled or cross-axis autopilot control concept is presented which can provide a significant increase in the usable range of angle of attack for aerodynamically controlled tactical missiles without an attendent increase in either steering response time or roll channel bandwidth. The unique feature of the coupled control system design is that adequate airframe stability can be maintained in the presence of aerodynamic cross-coupling at large angles of attack without either physically rolling the airframe to a preferred orientation with respect to the airstream or increasing the bandwidth of the roll system. Stability is maintained by intentionally cross-coupling sensor signals among the control channels (i.e., roll sensor signals into steering control, and vice versa) at large angles of attack. In effect, the intentional cross-channel coupling partially cancels the destabilizing effect of the interchannel aerodynamic coupling.
On the Formation of an Eccentric Disk via Disruption of a Bulge Core near a Massive Black Hole

We consider the possibility that an infalling bulge or stellar cluster could form an eccentric disk following tidal disruption by a massive black hole in the center of a galaxy. As a function of central black hole mass, we constrain the core radii and central densities of cluster progenitors capable of becoming nearly Keplerian disks that can support lopsided slow modes. We find that progenitor stellar clusters with core radii less than a parsec and densities above a few times 105 M⊙ pc-3 are likely eccentric disk progenitors near a massive black hole of mass 107–108 M⊙. Lower density and larger progenitor cores are capable of causing eccentric stellar disks near more massive black holes. Our constraints on the progenitors are consistent with existing N-body simulations, which in one case has produced an eccentric disk. For M31 and NGC 4486B, the estimated progenitor clusters are dense and compact compared with Galactic globular clusters; however, the nuclei of nearby galaxies, such as M33, M32, and M31 itself, are in the right regime. If galaxy mergers can create eccentric disks, then they would be a natural consequence of hierarchical galaxy formation.
On the independence number of graphs with maximum degree 3

Let G be an undirected graph with maximum degree at most 3 such that G does not contain any of the three graphs given in the paper as a subgraph. We prove that the independence number of G is at least n(G)/3+nt(G)/42, where n(G) is the number of vertices in G and nt(G) is the number of nontriangle vertices in G. This bound is tight as implied by the well-known tight lower bound of 5n(G)/14 on the independence number of triangle-free graphs of maximum degree at most 3. We show some algorithmic applications of the aforementioned combinatorial result to the area of parameterized complexity. We present a linear-time kernelization algorithm for the independent set problem on graphs with maximum degree at most 3 that computes a kernel of size at most 140k/47<3k, where k is the given parameter. This improves the known 3k upper bound on the kernel size for the problem, and implies a 140k/93 lower bound on the kernel size for the vertex cover problem on graphs with maximum degree at most 3.
Prehospital resuscitation practices: a survey of prehospital providers

Numerous factors affect decision making in the prehospital provision of resuscitative care. This study was undertaken to determine current practices involved in the initiation, continuation and termination of resuscitative efforts, and the impact of advance directives, in the prehospital resuscitation setting. This cross-sectional mailed questionnaire surveyed 3807 members of the National Association of Emergency Medical Technicians. The study instrument included questions regarding the termination and withholding of resuscitative efforts in the prehospital setting, as well as survival rates, local protocols and compliance with advance directives. Of 1546 respondents (41% response rate), with a mean 9.0 years of experience, most (89%) indicated that they would withhold resuscitative efforts in the presence of an official state-approved advance directive. However, very few providers would withhold resuscitative efforts if only an unofficial document (4%) or verbal report of an advance directive (10%) were available. Providers with more than 10 years experience were more likely to withhold resuscitation attempts in the presence of only a verbal report of an advance directive (p = 0.02, Chi-square), and were more likely to withhold resuscitation attempts in situations they considered futile (p = 0.001, Chi-square). Most (77%) respondents have local EMS guidelines for termination of resuscitation in the prehospital setting, but 23% of those consider existing guidelines to be inadequate. The majority of prehospital providers stated that they honor official state-approved advance directives, but do not follow directives from unofficial documents or verbal reports of advance directives. More experienced providers stated that they withhold resuscitative efforts more often in futile situations, or in the presence of unofficial advance directives. Advance directives should be utilized more uniformly among patients who wish to forgo resuscitative efforts in the event of cardiac arrest. Because many local protocols are judged to be inadequate, we support the institution of improved clinical guidelines regarding the prehospital termination of resuscitative efforts.
New constraints on chiral gauge theories

Abstract Recently, a new constraint on the structure of a wide class of strongly coupled field theories has been proposed. It takes the form of an inequality limiting the number of degrees of freedom in the infrared description of a theory to be no larger than the number of underlying, ultraviolet degrees of freedom. Here we apply this inequality to chiral gauge theories. For some models we find that it is always satisfied, while for others we find that the assumption of the validity of the inequality implies a strong additional restriction on the spectrum of massless composite particles.
Highly enantioselective epoxidation of enol silyl ethers and esters

Abstract High enantioselectivities have been obtained for asymmetric epoxidation of enol silyl ethers and asters using a fructose-derived chiral ketone as catalyst and Oxone as oxidant.
Engineering a successful mission: Lessons from the Lunar Reconnaissance Orbiter

Schedule pressure is common in the commercial world, where late delivery of a product means delayed income and loss of profit.12 Research spacecraft developed by NASA, on the other hand, tend to be driven by the high cost of launch vehicles and the public scrutiny of failure—the primary driver is ensuring proper operation in space for a system that cannot be retrieved for repair. The Lunar Reconnaissance Orbiter (LRO) development faced both schedule pressure and high visibility. The team had to balance the strong push to meet a launch date against the need to ensure that this first mission for Exploration succeeded. This paper will provide an overview of the mission from concept through its first year of operation and explore some of the challenges the systems engineering team faced taking a mission from preliminary design review to pre-ship review in 3 years.
Testing alternative theories of gravity using LISA

We investigate the possible bounds which could be placed on alternative theories of gravity using gravitational wave detection from inspiralling compact binaries with the proposed LISA space interferometer. Specifically, we estimate lower bounds on the coupling parameter ω of scalar–tensor theories of the Brans–Dicke type and on the Compton wavelength of the graviton λg in hypothetical massive graviton theories. In these theories, modifications of the gravitational radiation damping formulae or of the propagation of the waves translate into a change in the phase evolution of the observed gravitational waveform. We obtain the bounds through the technique of matched filtering, employing the LISA sensitivity curve generator (SCG), available online. For a non-spinning neutron star on a quasi-circular inspiral into a non-spinning 103M⊙ black hole in the Virgo Cluster, in a two-year integration, we find a lower bound ω > 3 × 105. For lower-mass black holes, the bound could be as large as 2 × 106. The bound is independent of LISA arm length, but is inversely proportional to the LISA position noise error, under the assumption that position error noise dominates laser shot noise. Lower bounds on the graviton Compton wavelength ranging from 1015 km to 5 × 1016 km can be obtained from one-year observations of massive binary black-hole inspirals at cosmological distances (3 Gpc) for masses ranging from 104 to 107M⊙. For the highest-mass systems (107M⊙), the bound is proportional to (LISA arm length)1/2 and to (LISA acceleration noise)−1/2. For the others, the bound is independent of these parameters because of the dominance of white-dwarf confusion noise in the relevant part of the frequency spectrum. These bounds improve and extend earlier work which used analytic formulae for the noise curves.
Photodegradation mechanisms of tetraphenyl butadiene coatings for liquid argon detectors

We report on studies of degradation mechanisms of tetraphenyl butadiene (TPB) coatings of the type used in neutrino and dark matter liquid argon experiments. Using gas chromatography coupled to mass spectrometry we have detected the ultraviolet-blocking impurity benzophenone. We monitored the drop in performance and increase of benzophenone concentration in TPB plates with exposure to ultraviolet (UV) light, and demonstrate the correlation between these two variables. Based on the presence and initially exponential increase in the concentration of benzophenone observed, we propose that TPB degradation is a free radical-mediated photooxidation reaction, which is subsequently confirmed by displaying delayed degradation using a free radical inhibitor. Finally we show that the performance of wavelength-shifting coatings of the type envisioned for the LBNE experiment can be improved by 10-20%, with significantly delayed UV degradation, by using a 20% admixture of 4-tert-Butylcatechol.
Incremental discovery of prominent situational facts

We study the novel problem of finding new, prominent situational facts, which are emerging statements about objects that stand out within certain contexts. Many such facts are newsworthy—e.g., an athlete's outstanding performance in a game, or a viral video's impressive popularity. Effective and efficient identification of these facts assists journalists in reporting, one of the main goals of computational journalism. Technically, we consider an ever-growing table of objects with dimension and measure attributes. A situational fact is a “contextual” skyline tuple that stands out against historical tuples in a context, specified by a conjunctive constraint involving dimension attributes, when a set of measure attributes are compared. New tuples are constantly added to the table, reflecting events happening in the real world. Our goal is to discover constraint-measure pairs that qualify a new tuple as a contextual skyline tuple, and discover them quickly before the event becomes yesterday's news. A brute-force approach requires exhaustive comparison with every tuple, under every constraint, and in every measure subspace. We design algorithms in response to these challenges using three corresponding ideas—tuple reduction, constraint pruning, and sharing computation across measure subspaces. We also adopt a simple prominence measure to rank the discovered facts when they are numerous. Experiments over two real datasets validate the effectiveness and efficiency of our techniques.
Shareholder rights and the market reaction to Sarbanes-Oxley

Abstract The Sarbanes-Oxley Act of 2002 (SOX) was aimed at enhancing corporate governance, financial reporting, and audit functions. This study compares the market reaction of firms with weak and strong protection of shareholder rights to the passage of SOX. We find that firms with weak shareholder rights experienced positive abnormal returns when SOX was passed. This is consistent with the market perceiving that such firms would benefit from the governance reforms. In contrast, firms with strong shareholder rights did not experience a significant positive market reaction. We also find a significant increase in risk for firms with weak shareholder rights following the passage of SOX. In addition, we find that strong shareholder rights firms decreased shareholder protection after SOX, while weak shareholder rights firms did not change significantly from their pre-SOX protection levels. We find no evidence of abnormal long-run performance for firms that altered their shareholder protection following SOX.
Caffeinated Alcoholic Beverages - An Emerging Trend in Alcohol Abuse.

Alcohol use disorders are pervasive in society and their impact affects quality of life, morbidity and mortality, as well as individual productivity. Alcohol has detrimental effects on an individual’s physiology and nervous system, and is associated with disorders of many organ and endocrine systems impacting an individual’s health, behavior, and ability to interact with others. Youth are particularly affected. Unfortunately, adolescent usage also increases the probability for a progression to dependence. Several areas of research indicate that the deleterious effects of alcohol abuse may be exacerbated by mixing caffeine with alcohol. Some behavioral evidence suggests that caffeine increases alcohol drinking and binge drinking episodes, which in turn can foster the development of alcohol dependence. As a relatively new public health concern, the epidemiological focus has been to establish a need for investigating the effects of caffeinated alcohol. While the trend of co-consuming these substances is growing, knowledge of the central mechanisms associated with caffeinated ethanol has been lacking. Research suggests that caffeine and ethanol can have additive or synergistic pharmacological actions and neuroadaptations, with the adenosine and dopamine systems in particular implicated. However, the limited literature on the central effects of caffeinated ethanol provides an impetus to increase our knowledge of the neuroadaptive effects of this combination and their impact on cognition and behavior. Research from our laboratories indicates that an established rodent animal model of alcoholism can be extended to investigate the acute and chronic effects of caffeinated ethanol.
The role of betatron acceleration in complex solar bursts

The betatron mechanism was proposed by Brown and Hoyng (1975) as a means of producing the continuous, quasi-periodic electron acceleration which may occur in long-lasting hard X-ray events. In the present work, two pertinent facets of the betatron model are investigated: The possibility that the multiplicity characteristic of complex impulsive bursts is due to the betatron process; and the possibility that some or all of the second-stage emission during two-stage bursts can be attributed to betatron acceleration. To test for the pattern of X-ray spectral behavior predicted by the betatron model, a number of multiply-impulsive events (cf., Karpen et al., 1979) and two-stage bursts (cf., Frost and Dennis, 1971) were selected from the OSO-5 hard X-ray spectrometer data for in-depth analysis. The purely impulsive emissions show no signs of the effects of betatron action, thus eliminating this process as a potential source of impulsive-phase multiplicity. However, the spectral characteristics determined during the first few minutes of the second stage are found to be consistent with the predictions of the betatron model for the majority of the two-stage events studied. The betatron-acceleration mechanism thus is proposed as a common second-stage phenomenon, closely associated with the diverse phenomena at other wavelengths which characterize this phase of emission. The physical significance of the source parameters derived according to the model-fitting procedure are discussed in detail, and the role of the betatron process is evaluated in the broader context of present-day concepts of the second stage.
Synthesis and Conformational Studies of New Purine Isodideoxynucleosides

Abstract The synthesis and NMR conformational correlations (preferred syn or anti) of new isomeric dideoxynucleosides of potential antiviral interest are described. These compounds are related to the potently active anti-HIV compound, (S,S)-isodideoxy-adenosine. #Dedicated to Dr. Yoshihisa Mizuno on the occasion of his 75th birthday
Analytic measures and bochner measurability

Many authors have made great strides in extending the celebrated F. and M. Riesz Theorem to various abstract settings. Most notably, we have, in chronological order, the work of Bochner [1], Helson and Lowdenslager [7], de Leeuw and Glicksberg [4], and Forelli [6]. These formidable papers build on each other’s ideas and provide broader extensions of the F. and M. Riesz Theorem. Our goal in this paper is to use the analytic Radon-Nikodým property and prove a representation theorem (Main Lemma 2.2 below) for a certain class of measure-valued mappings on the real line. Applications of this result yield the the main theorems from [4] and [6]. First, we will review briefly the results with which we are concerned, and describe our main theorem. The F. and M. Riesz Theorem states that if a complex Borel measure μ on the circle is such that ∫ π
A Reduced Order Model of Unsteady Flows in Turbomachinery

A novel technique for computing unsteady flows about turbomachinery cascades is presented. Starting with a frequency domain CFD description of unsteady aerodynamic flows, we form a large, sparse, generalized, non-Hermitian eigenvalue problem that describes the natural modes and frequencies of fluid motion about the cascade. We compute the dominant left and right eigenmodes and corresponding eigenfrequencies using a Lanczos algorithm. Then, using just a few of the resulting eigenmodes, we construct a reduced order model of the unsteady flow field. With this model, one can rapidly and accurately predict the unsteady aerodynamic loads acting on the cascade over a wide range of reduced frequencies and arbitrary modes of vibration. Moreover, the eigenmode information provides insights into the physics of unsteady flows. Finally we note that the form of the reduced order model is well suited for use in active control of aeroelastic and aeroacoustic phenomena.
The homomorphism domination exponent

We initiate a study of the homomorphism domination exponent of a pair of graphs F and G, defined as the maximum real number c such that |Hom(F,T)|>=|Hom(G,T)|^c for every graph T. The problem of determining whether HDE(F,G)>=1 is known as the homomorphism domination problem, and its decidability is an important open question arising in the theory of relational databases. We investigate the combinatorial and computational properties of the homomorphism domination exponent, proving upper and lower bounds and isolating classes of graphs F and G for which HDE(F,G) is computable. In particular, we present a linear program computing HDE(F,G) in the special case, where F is chordal and G is series-parallel.
A NEW STRUCTURAL FORM OF TIN AS A DOUBLE CUBE. A HEPTANUCLEAR TIN-SULFUR CLUSTER

Abstract Recently, we reported new classes of organooxotin compounds in the form of cubes, 1.2 drums,3-6 and oxygen-capped cluster.2,6,7 The faces of these clusters consist of either four- or six-membered Sn-O rings. The cube and the drum have the same empirical composition, [R'Sn(O)O2PR2] n n = 4 and 6, respectively, whereas the oxygen-capped cluster, [(R'Sn(OH)O2PR2)3O][R2PO2], resembles a cube with one corner missing. 119Sn NMR spectra show that the drum6 and the cube2 forms undergo hydrolysis in solution giving oxygen-capped clusters. Heating the latter regenerates the starting drum6 or cube,8 thus showing the reaction to be reversible. In all of these compositions, tin is hexacoordinated, and chelating phosphinate or phosphate ligands span adjacent tin atoms.
Higgs boson production in nucleus-nucleus collisions

Cross-section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two-photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two-photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.
MIMO-assisted channel-based authentication in wireless networks

Multiple-input multiple-output (MIMO) techniques allow for multiplexing and/or diversity gain, and will be widely deployed in future wireless systems. In this paper, we propose a MIMO-assisted channel-based authentication scheme, exploiting current channel estimation mechanisms in MIMO systems to detect spoofing attacks with very low overhead. In this scheme, the use of multiple antennas provides extra dimensions of channel estimation data, and thus leads to a "security gain" over single-input single-output (SISO) systems. We investigate the security gain of MIMO systems in several system configurations via simulations for a specific real indoor environment using ray-tracing software. We also discuss the effect of increasing the number of transmit and receive antennas on the security gain and contrast that to the diversity/multiplexing gain.
Deformation Quantization, Superintegrability, and Nambu Mechanics

Phase Space is the framework best suited for quantizing superintegrable systems—systems with more conserved quantities than degrees of freedom. In this quantization method, the symmetry algebras of the hamiltonian invariants are preserved most naturally. We illustrate the power and simplicity of the method through new applications to nonlinear σ-models, specifically for Chiral Models and de Sitter N-spheres, where the symmetric quantum hamiltonians amount to compact and elegant expressions, in accord with the Groenewold-van Hove theorem. Additional power and elegance is provided by the use of Nambu Brackets (linked to Dirac Brackets) involving the extra invariants of superintegrable models. The quantization of Nambu Brackets is then successfully compared to that of Moyal, validating Nambu’s original proposal, while invalidating other proposals.
Moire Strain Gauge With High Sensitivity

A microcomputer-based moire strain gauge with high sensitivity is developed that is capable of measuring strain automatically.
CompatPM : Enabling Energy Efficient Multimedia Workloads for Distributed Mobile Platforms

The computation and communication abilities of modern platforms are enabling increasingly capable cooperative distributed mobile systems. An example is distributed multimedia processing of sensor data in robots deployed for search and rescue, where a system manager can exploit the application's cooperative nature to optimize the distribution of roles and tasks in order to successfully accomplish the mission. Because of limited battery capacities, a critical task a manager must perform is online energy management. While support for power management has become common for the components that populate mobile platforms, what is lacking is integration and explicit coordination across the different management actions performed in a variety of system layers. This papers develops an integration approach for distributed multimedia applications, where a global manager specifies both a power operating point and a workload for a node to execute. Surprisingly, when jointly considering power and QoS, experimental evaluations show that using a simple deadline-driven approach to assigning frequencies can be non-optimal. These trends are further affected by certain characteristics of underlying power management mechanisms, which in our research, are identified as groupings that classify component power management as "compatible" (VFC) or "incompatible" (VFI) with voltage and frequency scaling. We build on these findings to develop CompatPM, a vertically integrated control strategy for power management in distributed mobile systems. Experimental evaluations of CompatPM indicate average energy improvements of 8% when platform resources are managed jointly rather than independently, demonstrating that previous attempts to maximize battery life by simply minimizing frequency are inappropriate from a platform-level perspective.
An Overview of the LADEE Ultraviolet-Visible Spectrometer

The Ultraviolet-Visible Spectrometer (UVS) instrument, which flew on the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft (SC), was one of three science instruments used to characterize the lunar exosphere. UVS is a point spectrograph operating between 230–810 nm and used its two optical apertures to make observations of the exosphere just above the surface at a range of local times and altitudes, as well as making solar occultation measurements at the lunar sunrise terminator. The instrument was led out of NASA Ames Research Center with primary hardware being provided by Draper Laboratories. Final instrument integration, testing and operations were performed at NASA Ames. Over the course of the 140-day LADEE mission UVS acquired more than 1 million spectra, providing a unique data set for lunar exosphere gasses and dust.
Do Bonds Span the Fixed Income Markets? Theory and Evidence for Unspanned Stochastic Volatility

Most term structure models assume bond markets are complete, that is, that all fixed income derivatives can be perfectly replicated using solely bonds. However, we find that, in practice, swap rates have limited explanatory power for returns on at-the-money straddles-portfolios mainly exposed to volatility risk. We term this empirical feature "unspanned stochastic volatility" (USV). While USV can be captured within an HJM framework, we demonstrate that bivariate models cannot exhibit USV We determine necessary and sufficient conditions for trivariate Markov affine systems to exhibit USV For such USV models, bonds alone may not be sufficient to identify all parameters. Rather, derivatives are needed.
Global wire routing in two-dimensional arrays

We examine the problem of routing wires of a VLSI chip, where the pins to be connected are arranged in a regular rectangular array. We obtain tight bounds for the worst-case “channel-width” needed to route ann×n array, and develop provably good heuristics for the general case. Single-turn routings are proved to be near-optimal in the worst-case. A central result of our paper is a “rounding algorithm” for obtaining integral approximations to solutions of linear equations. Given a matrix A and a real vector x, then we can find an integral x such that for alli, ¦x i -x i ¦ <1 and (Ax) i -(Ax) i <Δ. Our error bound Δ is defined in terms of sign-segregated column sums of A: $$\Delta = \mathop {\max }\limits_j \left( {\max \left\{ {\sum\limits_{i:a_{ij} > 0} {a_{ij} ,} \sum\limits_{i:a_{ij}< 0} { - a_{ij} } } \right\}} \right).$$
Design of an on-chip microscale nanoassembly system

A microscale nanoassembly system has been designed for the fabrication of nanodevices and in situ electromechanical characterisation of nanostructures. This system consists of four Microelectromechanical Systems (MEMS)-based nanomanipulators positioned around a centrally located port for introducing nanostructure samples. Each nanomanipulator is composed of an XYZ nanopositioning mechanism with an attached nanoprobe for interacting with the nanostructures. By simultaneously controlling the position of each of these nanoprobes, they can be used to cooperatively assemble complex structures. The static and dynamic motion characteristics of a prototype nanomanipulator have been measured, providing a non-linear calibration of the quasi-static input-output behaviour, as well as values for the system bandwidth and structural natural frequencies. Important operational issues including proposed manipulation schemes, precision motion control and integration with a Scanning Electron Microscope/Focused Ion Beam (SEM/FIB) instrument are also discussed.
Ambient Benzotriazole Ring Opening through Intermolecular Radical Addition to Vinyltriazole

Radical addition to vinyltriazole was developed as a new approach to achieve 1,2,3-triazole ring opening under mild conditions. Through reagent control, excellent chemoselectivity was achieved, giving either nitrile under basic conditions or quinoxaline under neutral conditions. Reactivities made this method an attractive new reaction mode.
Catalytic Oxidative Carbonylation of Arylamines to Ureas with W(CO)6/I2 as Catalyst

The oxidative carbonylation of aniline to N,N′-diphenylurea was carried out by using W(CO)6 as the catalyst, I2 as the oxidant, CO as the carbonyl source and 4-(dimethylamino)pyridine (DMAP) as base. The reaction conditions were optimized with respect to different bases, molar ratio of DMAP/iodine, temperature, time, and CO pressure. Various p-substituted arylamines can be converted into the respective symmetrical and unsymmetrical N,N′-disubstituted ureas in moderate to good yields. The reaction demonstrated broad tolerance of functionality.
Collective Evidence for Inverse Compton Emission from External Photons in High-power Blazars

We present the first collective evidence that Fermi-detected jets of high kinetic power (L(sub kin)) are dominated by inverse Compton emission from upscattered external photons. Using a sample with a broad range in orientation angle, including radio galaxies and blazars, we find that very high power sources (L(sub kin) > 10(exp 45.5) erg/s) show a significant increase in the ratio of inverse Compton to synchrotron power (Compton dominance) with decreasing orientation angle, as measured by the radio core dominance and confirmed by the distribution of superluminal speeds. This increase is consistent with beaming expectations for external Compton (EC) emission, but not for synchrotron self Compton (SSC) emission. For the lowest power jets (L(sub kin) < 10(exp 43.5) erg /s), no trend between Compton and radio core dominance is found, consistent with SSC. Importantly, the EC trend is not seen for moderately high power flat spectrum radio quasars with strong external photon fields. Coupled with the evidence that jet power is linked to the jet speed, this finding suggests that external photon fields become the dominant source of seed photons in the jet comoving frame only for the faster and therefore more powerful jets.
Managing the census data base: data description, acquisition, and manipulation

The U.S. Bureau of the Census collects and maintains a broad base of socio-economic and demographic data on population and housing in the United States. Summarizations and statistical information from this data base are made available to the public in printed reports. In addition, portions of the data are made available in machine-readable form, and thus are appropriate input for further research studies.For most potential users, however, many obstacles exist in making use of the machine-readable Census data. These obstacles may be classified into three areas: the identification and selection of relevant data items from the available data to support a given research objective, the acquisition of accurate and complete data, and the physical storage and processing of such a large data base.This paper discusses each of these problem areas and identifies the factors involved. Illustrations of possible solutions are presented, based on the author's experience with the Census data base at the University of Pennsylvania. Guidelines for dealing with such problems are provided for other prospective users. Finally, some general recommendations are made for avoiding or reducing these types of problems in future Census data products.
Morse functions statistics

We answer a question of Arnold concerning the growth rate of the number of Morse functions on the two-sphere.
On reductions of NP sets to sparse sets

Ogiwara and Watanabe showed that if SAT is bounded truth-table reducible to a sparse set, then P = NP. In this paper we simplify their proof, strengthen the result and use it to obtain several new results. Among the new results are the following:*Applications of the main theorem to log-truth-table and log-Turing reductions of NP sets to sparse sets. One typical example is that if SAT is log-truth-table reducible to a sparse set then NP is contained in DTIME (2^O^(^l^o^g^^^2^n^)). *Generalizations of the main theorem which yields results similar to the main result at arbitrary levels of the polynomial hierarchy and which extend as well to strong nondeterministic reductions. *The construction of an oracle relative to which P NP but there are NP-complete sets which are f(n)-tt-reducible to a tally set, for any f(n) @e @w(log n). This implies that, up to relativization, some of our results are optimal.
Jamming and growth of dynamical heterogeneities versus depth for granular heap flow

We report on grain dynamics versus depth for steady-state gravity-driven flow of grains along a heap formed between two parallel sidewalls. Near the surface the flow is steady and fast, while far below there is no flow whatsoever; therefore, a jamming transition occurs where depth is an effective control parameter for setting the distance from the transition. As seen previously, the time-averaged velocity profile along the sidewall exhibits a nearly exponential decay vs. depth. Using speckle-visiblility spectroscopy (SVS), we find that velocity fluctuations grow relative to the average on approach to jamming. Introducing an image-based order parameter and the variance in its temporal decay at a given depth, we also characterize the spatially heterogeneous nature of the dynamics and find that it increases on approach to jamming. In particular, the important time and length scales for dynamical heterogeneities are found to grow almost exponentially as a function of depth. These dynamical changes occur without noticeable change in structure, and are compared to behavior found by experiment and simulation elsewhere in order to test the universality of the jamming concept. In particular we find that the size of the heterogeneities scales as the inertia number raised to the −1/3 power, in agreement with two recent simulations.
Recovery of sparse 1-D signals from the magnitudes of their Fourier transform

The problem of signal recovery from the autocorrelation, or equivalently, the magnitudes of the Fourier transform, is of paramount importance in various fields of engineering. In this work, for one-dimensional signals, we give conditions, which when satisfied, allow unique recovery from the autocorrelation with very high probability. In particular, for sparse signals, we develop two non-iterative recovery algorithms. One of them is based on combinatorial analysis, which we prove can recover signals upto sparsity o(n1/3) with very high probability, and the other is developed using a convex optimization based framework, which numerical simulations suggest can recover signals upto sparsity o(n1/2) with very high probability.
Reply to Commentators

Professor Sherman raises issues which emerge from, and are situated within, ongoing philosophical debate, -in this case between the Stoics and other schools. This is the perspective that I have emphasized in my book, and both of her points form interesting extensions to the debates that I trace therephilosophical conversations, as she calls them, of some liveliness and interest to us as well as indications of distance or convergence between different ancient schools of thought. Aristotle's moral theory has often, and rightly, been commended for its attention to character and moral development, and he gives prominence to the development of the agent's emotions and feelings, as well as more purely intellectual development. The virtuous agent not only discerns what is the right thing to do, and does so as a matter of settled disposition, she has the appropriate emotional reaction to this. Aristotle's theory of virtue as being 'in a mean' covers emotions as well as actions: the virtuous person's feelings have been modified and transformed by the gradual transformation of her ethical intelligence. The result is that within the theory there is an important distinction between the fully virtuous person, who does the virtuous thing not only for the right reason but gladly, with no sense of struggle or loss, and the merely self-controlled person, who has to fight down contrary inclinations. In the book I claim that, although we associate this view of the place of the emotions in virtue especially with Aristotle, the kind of distinction that results between the fully virtuous and the merely self-controlled is widely accepted as something that a theory of virtue ought to be able to account for. Authors like Plutarch describe the difference between the conflicted, self-controlled person and the innerly harmonious, virtuous person in ways that show that the contrast is taken to be common ground. When the Stoics, then, say that the emotions are all bad and should be removed, they seem to be flouting the opinions both of the wise and of the many. I think that their position is, as often, less disagreeable to common sense when spelled out fully than it appears to be in isolation. Accordingly, I lay out some points in which it can be claimed that the more familiar Aris-
The Sun is a plasma diffuser that sorts atoms by mass

The Sun is a plasma diffuser that selectively moves light elements like H and He and the lighter isotopes of each element to its surface. The Sun formed on the collapsed core of a supernova (SN) and is composed mostly of elements made near the SN core (Fe, O, Ni, Si, and S), like the rocky planets and ordinary meteorites. Neutron emission from the central neutron star triggers a series of reactions that generate solar luminosity, solar neutrinos, solar mass fractionation, and an outpouring of hydrogen in the solar wind. Mass fractionation seems to have operated in the parent star and likely occurs in other stars as well.
Automorphisms of the complex of curves

This goal of the paper is to show that the automorphisms of the complex of curves in a surface are induced by the self-homeomorphisms of the surface except the surface is the 2-holed torus.
MOLE-FRACTION IMAGING OF TRANSVERSE INJECTION IN A DUCTED SUPERSONIC FLOW

Laser-induced iodine fluorescence has been used to generate two-dimensional images of the mixing characteristics of air injected transversely as underexpanded jets behind a rearward-facing step into a ducted Mach 2 freestream; the images thus obtained were processed digitally in order to yield planar-injectant mole fraction distributions. The resulting planar images represent a three-dimensional data base of the injectant mole fraction distribution throughout the flowfield which is then used to reconstruct images exhibiting mole-fraction distributions normal to the duct. These images furnish a direct representation of the evolution of supersonic mixing along the duct, and facilitate the development of one-dimensional mixing schedules on the basis of the three-dimensional data base.