cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermal Properties of Silica Aerogel Formula

The thermal conductivity of silica aerogel developed in this research program was measured using the transient hot-wire technique. The thermal conductivity of monolithic samples drops significantly from 9.3 mW/m · K to 3.2 mW/m · K with modest pressure reduction from 1 atm to 0.1 atm. The same aerogel in granular form has a thermal conductivity of 15.0 mW/m · K at ambient gas pressure with a modest compression applied to compact the granules and reduce the air void sizes. Radiation heat transfer in the hot-wire test may not be representative of its contribution in large scale applications. Measurements of the monochromatic extinction coefficient over the wavelengths of interest resulted in a Rosseland mean extinction coefficient of 2400 m−1 at 300 K. The small thermal penetration distance during the hot-wire measurements suggest that in actual use radiation could contribute approximately 2.5 mW/m · K with a possible upper limit of 3.0 mW/m · K to the effective thermal conductivity over that measured using the transient hot-wire method.
DVI — A digital multimedia technology

A DIGITAL PRESENTATION TECHNOLOGY that manages anything from text to full motion video has the potential of expanding the usefulness of personal computers, while rendering them less intimidating.
Why are X-Ray Sources in the M31 Bulge So Close to Planetary Nebulae?

We compare a deep (37 ks) Chandra ACIS-S image of the M31 bulge with deep [O III] Local Group Survey data of the same region. Through precision image alignment using globular cluster X-ray sources, we are able to improve constraints on possible optical/X-ray associations suggested by previous surveys. Our image registration allows us to rule out several emission-line objects, previously suggested to be the optical counterparts of X-ray sources, as true counterparts. At the same time, we find six X-ray sources peculiarly close to strong [O III] emission-line sources, classified as planetary nebulae (PNs) by previous optical surveys. Our study shows that, while the X-rays are not coming from the same gas as the optical line emission, the chances of these six X-ray sources lying so close to cataloged PNs is only ~1%, suggesting that there is some connection between these [O III] emitters (possibly PNs) and the X-ray sources. We discuss the possibility that these nebulae are misidentified supernova remnants, and we rule out the possibility that the X-ray sources are ejected X-ray binaries. There is a possibility that some cases involve a PN and a low-mass X-ray binary that occupy the same undetected star cluster. Beyond this unconfirmed possibility and the statistically unlikely one that the associations are spatial coincidences, we are unable to explain these [O III]/X-ray associations.
Na2EuAs2S5, NaEuAsS4, and Na4Eu(AsS4)2: controlling the valency of arsenic in polysulfide fluxes.

The reactivity of europium with As species in Lewis basic alkali-metal polysulfide fluxes was investigated along with compound formation and the As3+/As5+ interplay vis-a-vis changes in the flux basicity. The compound Na2EuAs2S5 containing trivalent As3+ is stabilized from an arsenic-rich polysulfide flux. It crystallizes in the monoclinic centrosymmetric space group P21/c. Na2EuAs2S5 has [As2S5]4– units, built of corner sharing AsS3 pyramids, which are coordinated to Eu2+ ions to give a two-dimensional (2D) layered structure. A sodium polysulfide flux with comparatively less arsenic led to the As5+ containing compounds NaEuAsS4 (orthorhombic, Ama2) and Na4Eu(AsS4)2 (triclinic, P1) depending on Na2S/S ratio. The NaEuAsS4 and Na4Eu(AsS4)2 have a three-dimensional (3D) structure built of [AsS4]3– tetrahedra coordinated to Eu2+ ions. All compounds are semiconductors with optical energy gaps of ∼2 eV.
Instability of cylindrical shells subjected to axisymmetric moving loads.

Donnell-type nonlinear theory for instability of cylindrical shell subjected to axisymmetric moving loads with constant velocity
Interlacing networks

Motivated by the problem of giving a bijective proof of the fact that the birational RSK correspondence satisfies the octahedron recurrence, we define interlacing networks, which are certain planar directed networks with a rigid structure of sources and sinks. We describe an involution that swaps paths in these networks and leads to Plucker-like three-term relations among path weights. We show that indeed these relations follow from the Plucker relations in the Grassmannian together with some simple rank properties of the matrices corresponding to our interlacing networks. The space of matrices obeying these rank properties forms the closure of a cell in the matroid stratification of the totally nonnegative Grassmannian. Not only does the octahedron recurrence for RSK follow immediately from the three-term relations for interlacing networks, but also these relations imply some interesting identities of Schur functions reminiscent of those obtained by Fulmek and Kleber. These Schur function identities lead to some results on Schur positivity for expressions of the form s ? s ? - s λ s µ .
Trimethylsilyldiazomethane as a Versatile Stitching Agent for the Introduction of Aziridines into Functionalized Organic Molecules

A highly enantioselective route for the introduction of aziridines into functionalized organic molecules was developed via a tandem acylation and aziridination of TMSCHN2.
Radio detection of ultra high energy neutrinos

Abstract Recent evidence for observation of the Greisen–Zatsepin–Kuzmin (GZK) cutoff in the cosmic ray spectrum has a number of profound implications for our understanding of high energy astroparticle physics. This GZK process itself produces neutrinos that are strongly believed to be both spectrally and spatially correlated to high energy cosmic ray particles above 100 EeV. In the 1960's Askaryan predicted that spatially compact nature of electromagnetic showers produced from the interaction of such high energy neutrinos would lead to coherent Cherenkov radiation. In June 2006 these Askaryan effect predictions were verified for emulated EeV showers in a 7 ton ice target at SLAC. A number of current and future experiments are now actively exploiting this radio detection method to search for the “guaranteed” GZK flux of high energy neutrinos. None have yet been observed, though the sensitivity of the detectors is just now approaching the predicted range. The ANtarctic Impulsive Transient Antenna (ANITA) experiment, a long-duration balloon operating at an altitude of 37 km, flew for over a month during December 2006–January 2007, and again December 2008–January 2009. In the longer term, a large-scale terrestrial radio array opens the possibility to probe deep inelastic neutrino-nucleon scattering at center of mass energies well above those of any proposed future collider. Prototype instrumentation stations have been evaluated. Essential to the realization of these experiments has been the development of affordable instrumentation with adequate radio frequency performance.
Preorganization—From Solvents to Spherands

This article assesses the importance of molecular preorganization to the rapidly developing field of complexation involving designed synthetic organic compounds. Since its birth as a science, organic chemistry has drawn heavily on biological chemistry as a vast storehouse of evolutionary structures, reactions, and control mechanisms that serve as inspiration for designed organic-compounds mimics. Biological systems, through highly structured complexation, accomplish complicated tasks. The receptor sites of enzymes, the genes, the antibodies, and ionophores possess high degree of preorganization. In other words, their functional groups act cooperatively as binding or catalytic sites which are largely collected and oriented prior to complexation.—The strength of the organic chemist derives from his ability to design organic compounds, organic reactions, synthetic sequences, and test systems to evaluate hypotheses. The design of highly structured complexs and the discovery of the rules that govern their behavior are described here. Research in this field is particularly rewarding because scientific and aesthetic content merge and become visible in the structures of many of the complexes.
The sorting index

We consider a bivariate polynomial that generalizes both the length and reflection length generating functions in a finite Coxeter group. In seeking a combinatorial description of the coefficients, we are led to the study of a new Mahonian statistic, which we call the sorting index. The sorting index of a permutation and its type B and type D analogues have natural combinatorial descriptions which we describe in detail.
The F-Signature and Strong F-Regularity

This is a revised version, incorporating referee's comments, of an article published in Mathematical Research Letters, 10 (2003), no. 1, 51-56.
Effects of A23187 upon cortical granule exocytosis in eggs of Brachydanio.

The effects of the divalent ionophore A23187 upon unfertilized eggs of the freshwater teleost fish, Brachydanio rerio, have been examined by light, scanning (SEM) and transmission (TEM) electron microscopy. Treatment of eggs with micromolar amounts (1 μM, 10 μM) of A23187 triggers cortical granule exocytosis and elevation of the chorion. However, the exocytosis of cortical granules in ionophore-activated eggs is explosive and occurs more rapidly than in eggs naturally activated in conditioned tap water. Eggs treated with A23187 in a medium lacking extra-cellular calcium also show cortical granule exocytosis, suggesting strongly that egg activation in Brachydanio results from release of calcium primarily from intracellular stores; however, there is a distinct delay in the onset of cortical granule breakdown. Unfertilized eggs exposed to A23187 for 1-5 min show noticeable disturbances in cell surface topography, including loss of microplicae and the appearance of prominent membrane-limited blebs.To determine if cortical granule exocytosis is self-propagating once initiated, A23187 was applied to a localized portion of the unfertilized egg surface, using either a G-50 sephadex gel bead or a 1 mm glass capillary tube. Eggs placed in continuous contact for 15 min with a bead coated with 10 μM A23187 show neither exocytosis of cortical granules nor elevation of the chorion. All eggs exhibit exocytosis when positioned against a glass rod coated with 1 μM A23187. The cortical granule breakdown is partial and restricted to less than 50% of the egg surface in most cells. The complete exocytosis of cortical granules in the zebra danio egg appears to require the stimulation and release of calcium from multiple sites over the cortex.
Parameters for evaluation of the fate, transport, and environmental impacts of chemical agents in marine environments.

Abstract : 313 references were reviewed to obtain data relevant to the fate, transport, and environmental impacts of chemical agents in marine environments. The review covers the chemical agents phosgene, cyanogen chloride, hydrogen cyanide, sulfur mustard, Lewisite nitrogen mustard \201HN1\202, Tabun, Sarin, and VX. Parameters covered in the review are boiling point, melting point, density, vapor pressure, solubility, Henry?s Law constant, partition coefficients, dissociation constants, and hydrolysis rate constants and products. Recent ecotoxicity data are also discussed. Data gaps for these parameters and agents are identified and prioritized. In addition to the specific data gaps, the authors have identified several general issues that extend beyond single compounds or types of data. Given the available data and what they suggest will be the dominant fate and transport mechanisms, there are no data gaps that leave one unable to conduct a reasonable assessment for any agent. The primary source of uncertainty in the evaluation of the fate, transport, and environmental impacts of these agents remains the rate at which they are released into the environment. The data gaps identified in this work appear to cause a significantly smaller level of uncertainty.
Higher Indicators for the Doubles of Some Totally Orthogonal Groups

We investigate the indicators for certain groups of the form ℤ k ⋊ D l and their doubles, where D l is the dihedral group of order 2l. We subsequently obtain an infinite family of totally orthogonal, completely real groups which are generated by involutions, and whose doubles admit modules with second indicator of −1. This provides us with answers to several questions concerning the doubles of totally orthogonal finite groups.
Modified Lead Calcium Titanate Ceramics with a Relatively Large Dielectric Constant for Hydrophone Applications

Modified lead titanate of the base composition (Pb,Ca)Ti-(Co,W)O3 + 0.01 mol % MnO was doped with 2 to 6 mol % strontium and barium to increase the dielectric constant, K, while preserving a high piezoelectric anisotropy (d33/d31). K was increased above 500 and a d33/d31 ratio of 34/1 was achieved when the composition Pb0.65Ca0.31Sr0.04Ti0.94-(Co0.5W0.5)0.06O3 + 0.01 mol% MnO was fabricated. The large d33/d31 resulted in an impressive hydrostatic piezoelectric coefficient (d(h) = 81 X 10(-12) m2/V). The relatively low transition temperature (T(c) = 120-degrees-C) did not result in an increased aging rate when samples were tested at 40-degrees-C and 99% humidity for 120 h after poling. A small tetragonality ratio (1.008) enabled saturation of ceramic properties at poling fields as low as 30 kV/cm at 100-degrees-C.
Discounting financial literacy: Time preferences and participation in financial education programs

Many policymakers and economists argue that financial literacy is key to financial well-being. But why do many individuals remain financially illiterate despite the benefits of being financially informed? This paper presents results from a field study linking individual decisions to acquire financial information to a normally unobservable characteristic: time preferences. We elicited time preferences using incentivized choice experiments for all individuals to whom a financial education program was offered. Our results show that individuals who choose to acquire personal financial information have substantially higher discount factors than individuals who do not. The results can be interpreted as non-participants discount the benefits of being financially literate more.
Biopolymers: origin, chemistry, and biology.

A brief statement concerning the way in which biopolymers may have originated in the nonbiological world is made, including experimental evidence. This also includes a discussion of such matters as the way in which the code might have originated, that is, the relationship between polypeptides and polynucleotides as well as the secondary and tertiary structure resulting from the primary structure determination. The importance of the interaction of biopolymers with lipids for the formation of limiting membranes, leading to the formation of cells and other self-organizing cellular type organelles, is discussed. Thus, the second critical physical-chemical problem for cellular organization, namely, the biopolymer-lipid interaction, is now coming under scrutiny, both in terms of synthetic systems as well as natural ones.
The effect of bacterial cell wall adsorption on mineral solubilities

In this study, we demonstrate that the adsorption of mineral-forming cations onto a bacterial surface can lead to enhanced mineral solubilities, and we present a thermodynamic approach for quantitatively modelling this bacterial effect. We measured the dissolution of CuO in abiotic systems and in systems that contained non-metabolic whole cells of the gram-positive bacterial species Bacillus subtilis. We measured Cu concentrations, both in solution and adsorbed onto the bacteria, and we also measured dissolved organic carbon content to deconvolve the role of cell lysis on mineral dissolution. In the bacteria-bearing systems, we observed greatly elevated extents of mineral dissolution relative to the abiotic controls, caused by high concentrations of Cu adsorbed onto the cell walls. Our results indicate that bacterial cell wall adsorption can significantly lower mineral saturation states in geologic systems, causing both an increase in the extent of mineral dissolution as well as an inhibition of secondary mineral formation.
Asymmetric synthesis of benzilic acid analogues using 8-phenylmenthol as a chiral auxiliary

Abstract Our program on the synthesis of 18 F-labeled muscarinic receptor ligands required the preparation of chiral fluoroalkyl benzilic acids. An enantioselective synthesis of substituted benzilic acids was achieved using 8-phenylmenthol as the chiral auxiliary. Grignard addition to the si face of 8-phenylmenthyl benzoylformate 7 proceeded with high selectivity. The results of the chiral induction support assignments of the chirality of benzilic acids previously resolved by crystallization. The method was used to synthesize (R)-quinuclidinyl-(R)-(4-iodo)benzilate, which proved identical to an authentic sample. In addition, the method allows the preparation of(R)- and (S)-fluoroethyl benzilic acids in a stereoselective manner.
Long-Memory and Level Shifts in the Volatility of Stock Market Return Indices

There has been interest in the possibility of confusing long memory and structural changes in level, and studies showed that when a short-memory process is contaminated by level shifts the estimate of the fractional differencing parameter is biased upward and the autocovariances decay slowly. We analyze the properties of the autocorrelation function, the periodogram, and the log periodogram estimate of the memory parameter when the level shift component is a mixture model. Our results explain many findings reported and uncover new features. We confront our theoretical predictions using log-squared returns as a proxy for the volatility of some assets returns, including daily S&P 500 returns over the period 1928–2002. The estimates follow patterns that would obtain if the process was short memory with level shifts instead of fractionally integrated. A simple test is also proposed, which reinforces this conclusion.
Rotordynamic coefficients measurements versus predictions for a high-speed flexure-pivot tilting-pad bearing (load-between-pad configuration)

Experimental dynamic force coefficients are presented for a four pad flexure-pivot tilting-pad bearing in load-between-pad configuration for a range of rotor speeds and bearing unit loadings. Measured dynamic coefficients have been compared to theoretical predictions using an isothermal analysis for a bulk-flow Navier-Stokes (NS) model. Predictions from two models-the Reynolds equation and a bulk-flow NS equation models are compared to experimental, complex dynamic stiffness coefficients (direct and cross-coupled) and show the following results: (i) The real part of the direct dynamic-stiffness coefficients is strongly frequency dependent because of pad inertia, support flexibility, and the effect of fluid inertia. This frequency dependency can be accurately modeled for by adding a direct added-mass term to the conventional stiffness/damping matrix model. (ii) Both models underpredict the identified added-mass coefficient (∼32 kg), but the bulk' flow NS equation predictions are modestly closer. (iii) The imaginary part of the direct dynamic-stiffness coefficient (leading to direct damping) is a largely linear function of excitation frequency, leading to a constant (frequency-independent) direct damping model. (iv) The real part of the cross-coupled dynamic-stiffness coefficients shows larger destabilizing forces than predicted by either model. The frequency dependency that is accounted for by the added mass coefficient is predicted by the models and arises (in the models) primarily because of the reduction in degrees of freedom from the initial 12 degrees (four pads times three degrees of freedom) to the two-rotor degrees of freedom. For the bearing and condition tested, pad and fluid inertia are secondary considerations out to running speed. The direct stiffness and damping coefficients increase with load, while increasing and decreasing with rotor speed, respectively. As expected, a small whirl frequency ratio (WFR) was found of about 0.15, and it decreases with increasing load and increases with increasing speed. The two model predictions for WFR are comparable and both underpredict the measured WFR values. Rotors supported by either conventional tilting-pad bearings or flexure-pivot tilting-pad (FPTP) bearings are customarily modeled by frequency-dependent stiffness and damping matrices, necessitating an iterative calculation for rotordynamic stability. For the bearing tested and the load conditions examined, the present results show that adding a constant mass matrix to the FPTP bearing model produces an accurate frequency-independent model that eliminates the need for iterative rotordynamic stability calculations. Different results may be obtained for conventional tilting-pad bearings (or this bearing at higher load conditions).
The Equilibrium and Optimal Timing of Price Changes

This paper studies the welfare properties of the equilibrium timing of price changes. Staggered price setting has the advantage that it permits rapid adjustment to firm-specific shocks, but the disadvantages that it causes unwanted fluctuations in relative prices and that, by creating price level inertia, it can increase aggregate fluctuations. Because each firm ignores its contribution to these problems, staggering can be a stable equilibrium even if it is highly inefficient. In addition, there can be multiple equilibria in the timing of prices changes; indeed, whenever there is an inefficient staggered equilibrium, there is also an efficient equilibrium with synchronized price setting.
Private and public disclosures and the efficiency of stock prices

In this paper I examine the effects of private and public disclosures on the informational efficiency of stock prices. In addition to making a public announcement such as an earnings announcement, a public firm can make private disclosure to an analyst. If the analyst's relative information advantage is below a threshold level, private disclosure to the analyst leads to more efficient stock price. I demonstrate that the allocation of information across market participants is an important determinant of price efficiency. While accounting regulators often argue the need for equal access to information, the paper shows that there are conditions under which a limited amount of informational inequality may lead to more efficient stock prices.
Nickel-Catalyzed Amination of Aryl Sulfamates and Carbamates Using an Air-Stable Precatalyst

A facile nickel-catalyzed method to achieve the amination of synthetically useful aryl sulfamates and carbamates is reported. Contrary to most Ni-catalyzed amination reactions, this user-friendly approach relies on an air-stable Ni(II) precatalyst, which, when employed with a mild reducing agent, efficiently delivers aminated products in good to excellent yields. The scope of the method is broad with respect to both coupling partners and includes heterocyclic substrates.
BEC–BCS crossover, phase transitions and phase separation in polarized resonantly-paired superfluids

Abstract We study resonantly-paired s-wave superfluidity in a degenerate gas of two species (hyperfine states labeled by ↑, ↓) of fermionic atoms when the numbers N↑ and N↓ of the two species are unequal, i.e., the system is “polarized.” We find that the continuous crossover from the Bose–Einstein condensate (BEC) limit of tightly-bound diatomic molecules to the Bardeen–Cooper–Schrieffer (BCS) limit of weakly correlated Cooper pairs, studied extensively at equal populations, is interrupted by a variety of distinct phenomena under an imposed population difference ΔN ≡ N↑ − N↓. Our findings are summarized by a “polarization” (ΔN) versus Feshbach-resonance detuning (δ) zero-temperature phase diagram, which exhibits regions of phase separation, a periodic FFLO superfluid, a polarized normal Fermi gas and a polarized molecular superfluid consisting of a molecular condensate and a fully polarized Fermi gas. We describe numerous experimental signatures of such phases and the transitions between them, in particular focusing on their spatial structure in the inhomogeneous environment of an atomic trap.
Kinetics of quasiparticle trapping in a Cooper-pair box

We study the kinetics of the quasiparticle capture and emission process in a small superconducting island (Cooper-pair box) connected by a tunnel junction to a massive superconducting lead. At low temperatures, the charge on the box fluctuates between two states, even and odd in the number of electrons. Assuming that the odd-electron state has the lowest energy, we evaluate the distribution of lifetimes of the even- and odd-electron states of the Cooper-pair box. The lifetime in the even-electron state is an exponentially distributed random variable corresponding to a homogenous Poisson process of ``poisoning'' the island with a quasiparticle. The distribution of lifetimes of the odd-electron state may deviate from the exponential one. The deviations come from two sources - the peculiarity of the quasiparticle density of states in a superconductor and the possibility of quasiparticle energy relaxation via phonon emission. In addition to the lifetime distribution, we also find spectral density of charge fluctuations generated by capture and emission processes. The complex statistics of the quasiparticle dwell times in the Cooper-pair box may result in strong deviations of the noise spectrum from the Lorentzian form.
Monte Carlo studies of transport in stellarators

Transport is studied in toroidal geometry by integrating the guiding‐center equations in magnetic coordinates and simulating collisions with a Monte Carlo collision operator. The effects of the ambipolar electric field on diffusion losses are determined for model magnetic fields and the correct magnetic field of the Advanced Toroidal Facility (ATF‐1) stellarator. Comparisons are made of the computed diffusion coefficients and the theoretically predicted values.
Measurement of the $W$ boson mass at the LHC

We explore the ability of the Large Hadron Collider to measure the mass of the W boson. We believe that a precision better than \(\sim 15\) MeV could be attained, based on a year of operation at low luminosity (\(10^{33}\,{\rm cm}^{-2}\,{\rm s}^{-1}\)). If this is true, this measurement will be the world's best determination of the W mass.
Acoustic vector-sensor beamforming and Capon direction estimation

We examine the improvement attained by using acoustic vector-sensors for direction-of-arrival (DOA) estimation, instead of traditional pressure sensors, via optimal performance bounds and particular estimators. By examining the Cramer-Rao bound in the case of a single source, we show that a vector-sensor array's smaller estimation error is a result of two distinct phenomena: (1) an effective increase in signal-to-noise ratio due to a greater number of measurements of phase delays between sensors and (2) direct measurement of the DOA information contained in the structure of the velocity field due to the vector sensors' directional sensitivity. Separate analysis of these two phenomena allows us to determine the array size, array shape, and SNR conditions under which the use of a vector-sensor array is most advantageous and to quantify that advantage. By extending the beamforming and Capon (1969) direction estimators to vector-sensors, we find that the vector-sensors' directional sensitivity removes all bearing ambiguities. In particular, even simple structures such as linear arrays can determine both azimuth and elevation, and spatially undersampled regularly spaced arrays may be employed to increase the aperture and, hence, the performance. Large sample approximations to the mean-square error matrices of the estimators are derived and their validity is assessed by Monte Carlo simulation.
Synthesis of 2-(2′,3′-dihydroxypropyl)-5-amino-2H-1,2,4-thiadiazol-3-one and 3-(2′,3′-dihydroxypropyl)-5-amino-3H-1,3,4-thiadiazol-2-one†‡

The synthesis of two new acyclic nucleoside analogs, 2-(2′,3′-dihydroxypropyl)-5-amino-2H-1,2,4-thiadiazol-3-one (1) and 3-(2′,3′-dihydroxypropyl)-5-amino-3H-1,3,4-thiadiazol-2-one (2), is reported. The first compound, 1, was obtained by reaction of 3-chloro-1,2-propanediol with the sodium salt of 5-amino-2H-1,2,4-thiadiazol-3-one (3) in anhydrous dimethylformamide. Similarly, 5-amino-3H-1,3,4-thiadiazol-2-one (4) reacted with 3-chloro-1,2-propanediol to give 2. The thiadiazole 4 was prepared by condensation-cyclization of hydrazothiodicarbonamide (9).
Massive Stars in the Quintuplet Cluster

We present near-infrared photometry and K-band spectra of newly identified massive stars in the Quintuplet cluster, one of the three massive clusters projected within 50 pc of the Galactic center. We find that the cluster contains a variety of massive stars, including more unambiguously identified Wolf-Rayet stars than any cluster in the Galaxy, and over a dozen stars in earlier stages of evolution, i.e., luminous blue variables (LBVs), Ofpe/WN9, and OB supergiants. One newly identified star is the second luminous blue variable in the cluster, after the "Pistol star." Although we are unable to provide certain spectral classifications for the five enigmatic Quintuplet-proper members, we tentatively propose that they are extremely dusty versions of the WC stars found elsewhere in the cluster and similar to the dozen or so known examples in the Galaxy. Although the cluster parameters are uncertain because of photometric errors and uncertainties in stellar models, i.e., extrapolating initial masses and estimating ionizing fluxes, we have the following conclusions. Given the evolutionary stages of the identified stars, the cluster appears to be about 4±1 Myr old, assuming coeval formation. The total mass in observed stars is ~103 M☉, and the implied mass is ~104 M☉, assuming a lower mass cutoff of 1 M☉ and a Salpeter initial mass function. The implied mass density in stars is greater than or similar to a few thousand M☉ pc-3. The newly identified stars increase the estimated ionizing flux from this cluster by about an order of magnitude with respect to earlier estimates, to 1050.9 photons s-1, or roughly what is required to ionize the nearby "Sickle" H II region (G0.18-0.04). The total luminosity from the massive cluster stars is ≈107.5 L☉, enough to account for the heating of the nearby molecular cloud, M0.20-0.033. We propose a picture that integrates most of the major features in this part of the sky, excepting the nonthermal filaments. We compare the cluster to other young massive clusters and globular clusters, finding that it is unique in stellar content and age, except, perhaps, for the young cluster in the central parsec of the Galaxy. In addition, we find that the cluster is comparable to small "super star clusters."
D3/D7 brane inflation and semilocal strings

Among the inflationary models based on string theory, the D3/D7 model has the advantage that the flatness of the inflaton potential can be protected even with moduli stabilization. However, the Abrikosov-Nielsen-Olesen BPS cosmic strings produced at the end of original D3/D7 inflation lead to an additional contribution to the CMB anisotropy. To make this contribution consistent with the WMAP results one needs an extremely small gauge coupling in the effective D-term inflation model. Such couplings may be difficult to justify in string theory. Here we develop a generalized version of the D3/D7 brane model, which leads to semilocal strings, instead of the topologically stable ANO cosmic strings. We show that the semilocal strings have unbroken supersymmetry when embedded into supergravity with FI terms. The energy of these strings is independent of their thickness. We confirm the existing arguments that strings of such type disappear soon after their formation and do not pose any cosmological problems, for any value of the gauge coupling. This should simplify the task of constructing fully realistic models of D3/D7 inflation.
Simulation of Deployment Dynamics of Inflatable Structures

Analytical simulation of the ine ation process of ine atable structures is key to assessing their robust deployment in a space environment. Although the problem seems to be intractable, a simplie ed e nite volume ine ation model is developed, which allows discretized description of the gas e ow, pressure variation, and resulting nonlinear large deformation throughout domains of the ine atable structure. Simulation results are presented along with convergence studies, which provide insight into the deployment of three different packaging/deployment schemes: Z-unfolding, rollout, and extrusion of a cylindrical tube. The proposed ine ation model is not limited to prismatic one-dimensional components and can be applied to ine atable shapes with complex cone gurations. As a validation of the numerical simulation, a laboratory experiment was conducted on the Z-folded cone guration. Generally, good agreement in the overall ine ation dynamics is observed between the analysis and experiment. EVERALspacemissionshaveconsideredtheuseoflightweight ine atable structures for components such as booms, sunshades, solar concentrators, solar sails, and antennas for nearly all aspects of Earth and space explorations. As a prelude to these missions, the ine atable antenna experiment (IAE) was deployed from the Space Shuttle Endeavour in May 1996 to demonstrate the readiness and reliabilityoftheine atabletechnologyforalarge14-mantennastructure in a realistic space environment. 1 One of the urgent technology issues revealed by the brief 80-min IAE e ight experiment was the need to better understand the dynamics of deploying ine atable structuresinspaceandhowthe ine ationprocessisine uenced by the deployment scheme. This includes the initial packaging and subsequent release and ine ation. Depending on the deployment scheme, large ine atable structures can be extremely e exible to the point of instability, especially during the early stages of ine ation. Rigidization can begin only after e nal deployment is achieved. Testing the deploymentof alargeine atableinan Earth environmentin the presence of gravity and air is of limited value for inferring its deploymentbehavior in space. Therefore, analytical models for simulating and predicting the dynamics of the ine ation process are essential tools for understanding ine atables’ deployment behavior in space environment and for guiding and improving future packaging and deployment concepts. To thisend,this paper explores theuse ofa e nite volume ine ation model that allows a tractable simulation of the deployment process of various ine atable cone gurations, from their initial stowed state to full deployment. Of interest here is a description of all states of ine ation as a function of time. Knowledge of all states of ine ation is essential for subsequent assessment of conditions of stability and controllability of the deployment process.
Public pensions, international affairs and divestment regulations: A critical analysis and call for a model law

This article undertakes a critical examination of the state laws of the United States requiring public pension funds to divest from companies that do business with Cuba, Iran, Syria and Sudan, countries that are currently listed as ‘state sponsors of terrorism’ by the federal government. The article finds that divestment statutes contain legal and public policy deficiencies that are worth revisiting and rectifying. The article argues that a model law that addresses the divestment schemes’ statutory deficiencies be drafted. The project posits that the voluntary adoption of the proposed model law by the states would ensure the constitutionality of the divestment statutes and would also protect pension fund employees, retirees and government employees. The project, to the best of the author's knowledge, is the first study that analyses the substance of state divestment statutes and places them in a comparative perspective to highlight the laws’ strengths and weaknesses.
ON THE GOUSSAROV–POLYAK–VIRO FINITE-TYPE INVARIANTS AND THE VIRTUALIZATION MOVE

In this paper, it is shown that there are no nonconstant Goussarov–Polyak–Viro finite-type invariants that are invariant under the virtualization move. As an immediate corollary, we obtain the theorem of [1] which states none of the Birman coefficients of the Jones–Kauffman polynomial are of GPV finite type.
A QUASI-STATIONARY SOLUTION TO GLIESE 436b's ECCENTRICITY

We investigate the possibility that the large orbital eccentricity of the transiting Neptune-mass planet Gliese 436b (Gl 436b) is maintained in the face of tidal dissipation by a second planet in the system. We find that the currently observed configuration can be understood if Gl 436b and a putative companion have evolved to a quasi-stationary fixed point in which the planets' orbital apses are co-linear and in which secular variations in the orbital eccentricities of the two planets have been almost entirely damped out. In our picture, the two planets are currently experiencing a long period of gradual orbital circularization. Specifically, if Gl 436b has a tidal Q ~ 300,000, similar to both the Jovian Q and to the upper limit for the Neptunian Q, then this circularization timescale can be of order τ ~ 8 Gyr given the presence of a favorably situated perturber. We adopt an octopole-order secular theory based on a Legendre expansion in the semimajor axis ratio a 1/a 2 to delineate well-defined regions of (P_c , M_c , e_c ) space that can be occupied by a perturbing companion. This description includes the leading-order effects of general relativity, and retains accuracy for perturbing companion planets that have high eccentricity. We incorporate the evolutionary effect of tidal dissipation into our secular model of the system, and solve the resulting initial value problems for a large sample of the allowed configurations. We find a locus of apsidally aligned configurations that are (1) consistent with the currently published radial velocity data, (2) consistent with the current lack of observed transit timing variations (TTVs), (3) subject to rough constraint on dynamical stability, and which (4) have damping timescales consistent with the current multi-Gyr age of the star. We then polish the stationary configurations derived from secular theory with full numerical integrations, and compute the TTVs and radial velocity half-amplitudes induced by the resulting configurations. We present our results in the form of candidate companion planets to Gl 436b. For these candidates, radial velocity half-amplitudes, K_c , are of order 3 m s^(-1), and the maximum amplitude of orbit-to-orbit TTVs are of order Δt = 1 s to Δt = 5 s. For the particular example case of a perturber with orbital period, P_c = 40 d, mass, M_c = 8.5 M ⊕, and eccentricity, e_c = 0.58, we confirm our semianalytic calculations with a full numerical three-body integration of the orbital decay that includes tidal damping and spin evolution. Additionally, we discuss the possibility of many-perturber stationary configurations, utilizing modified Laplace-Lagrange secular theory. We then perform a proof-of-concept tidally dissipated numerical integration with three planets, which shows the system approaching a triply circular state.
Institutional Ownership of Bank Shares

U.S. bank regulations weaken the incentives for market-based monitoring of bank CEOs, and bank assets are difficult for outside investors to value. Therefore, we analyzed factors that might influence institutional holdings of bank shares. Our primary expectation was that alignment of the economic interests of bank CEOs with those of bank shareholders would be particularly important in determining which banks attract institutional investment funds. Our results suggest that the sensitivity of a bank CEO's compensation to shareholder wealth does have a positive influence on the proportion of a bank's shares held by institutional investors. Additional evidence suggests that bank size is positively related to institutional ownership whereas capital adequacy and stock variance are negatively related to institutional ownership. In general, the evidence implies that when a company's quality is difficult for outside investors to determine, portfolio managers consider the economic incentives of company managers.
Improved computer method for polarity cross correlation

Abstract An improved computer method for polarity-correlation noise analysis yields increased throughout and provides for monitoring of discriminator bias.
Efficient parallel algorithms and software for compressed octrees with applications to hierarchical methods

We describe the design and implementation of efficient parallel algorithms, and a software library for the parallel implementation of compressed octree data structures. Octrees are widely used in supporting hierarchical methods for scientific applications such as the N-body problem, molecular dynamics and smoothed particle hydrodynamics. The primary goal of our work is to identify and abstract the commonalities present in various hierarchical methods using octrees, design efficient parallel algorithms for them, and encapsulate them in a software library. We designed provably efficient parallel algorithms and implementation strategies that perform well irrespective of the spatial distribution of data in the computational domain. The library will enable rapid development of applications, allowing application developers to use efficient parallel algorithms developed for this purpose, without the necessity of having detailed knowledge of the algorithms or of implementing them. The software is developed in C using the Message Passing Interface (MPI). We report experimental results on an IBM xSeries parallel computer.
Variable rate lattice VQ algorithm for vector subband coding

In this paper, a variable rate lattice VQ algorithm for vector subband coding is proposed. It is a modification of a two-stage vector quantization-lattice vector quantization (VQ-LVQ) algorithm introduced by J. Pan and T. R. Fischer. After the modification, the new algorithm is designed to target low-bit rate coding instead of moderate bit rate to high bit rate coding in the original design. The new algorithm has been applied to a low bit rate vector subband coding scheme. Simulation result shows it can reduce the memory requirement while offering even better rate-distortion performance (up to 1 db) than regular unstructured VQ.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Spin State and Moment of Inertia Characterization of 4179 Toutatis

The 4.5 km long near-Earth asteroid 4179 Toutatis has made close Earth flybys approximately every four years between 1992 and 2012, and has been observed with high-resolution radar imaging during each approach. Its most recent Earth flyby in 2012 December was observed extensively at the Goldstone and Very Large Array radar telescopes. In this paper, Toutatis' spin state dynamics are estimated from observations of five flybys between 1992 and 2008. Observations were used to fit Toutatis' spin state dynamics in a least-squares sense, with the solar and terrestrial tidal torques incorporated in the dynamical model. The estimated parameters are Toutatis' Euler angles, angular velocity, moments of inertia, and the center-of-mass-center-of-figure offset. The spin state dynamics as well as the uncertainties of the Euler angles and angular velocity of the converged solution are then propagated to 2012 December in order to compare the dynamical model to the most recent Toutatis observations. The same technique of rotational dynamics estimation can be applied to any other tumbling body, given sufficiently accurate observations.
On a Conjecture of Milnor about Volume of Simplexes

In, John Milnor conjectured that the volume of a hyperbolic or spherical n−simplex, considered as a function of the dihedral angles, can be extended continuously to the degenerated simplexes. Furthermore, he conjectured that the extended volume function is non-zero except in the closure of the space of Euclidean simplexes. The first part of the conjecture on the continuous extension was established in ( has a new proof of it which
DIVIDE: Distributed visual display of the execution of asynchronous, distributed algorithms on loosely coupled parallel processors

Abstract The issue of monitoring the execution of asynchronous, distributed algorithms on loosely coupled parallel processor systems is important for the purposes of (i) detecting inconsistencies and flaws in the algorithm; (ii) obtaining important performance parameters for the algorithm; and (iii) developing a conceptual understanding of the algorithm's behavior, for given input stimulus, through visualization. For a particular class of asynchronous distributed algorithms that may be characterized by independent and concurrent entities that execute asynchronously on multiple processors and interact with one another through explicit messages, information about the flow of messages and the activity of the processors may contribute significantly towards the conceptual understanding of the algorithm's behavior and the functional correctness of the implementation. The computation and subsequent display of important parameters, based upon the execution of the algorithm, is an important objective of DIVIDE. For instance, the mean and standard deviation values for the propagation delay of ATM cells between any two given Broadband-ISDN (BISDN) nodes in a simulation of BISDN network under stochastic input stimulus, as a function of time, are important clues to the degree of congestion in the Broadband-ISDN network. Although the execution of the algorithm typically generates high-resolution data, often, a coarse-level visual representation of the data may be useful in facilitating the conceptual understanding of the behavior of the algorithm. DIVIDE permits a user to specify a resolution less than that of the data from the execution of the algorithm, which is then utilized to coalesce the data appropriately. Given that this process requires significant computational power, for efficiency, DIVIDE distributes the overall task of visual display into a number of user-specified workstations that are configured as a loosely coupled parallel processor. DIVIDE has been implemented on a heterogeneous network of SUN Sparc 1+, Sparc 2, and 3 60 workstations, and performance measurements indicate significant improvement over that of a uniprocessor-based visual display.
MPEG-2 to H.263 transcoder

We present an MPEG-2 to H.263 transcoder that accepts an interlaced MPEG-2 bitstream as the input and produces a lower-bitrate progressive H.263 bitstream as the output. As both DVD and digital television may use MPEG-2 interlaced sequences, a potential application of such a transcoder is the transmission of a digital television signal over a wireless medium. Another application is transcoding interlaced DVD content for use on lower-resolution thin clients with progressive displays. The proposed algorithm exploits the properties of the MPEG-2 and H.263 compression standards to perform interlaced to progressive (field to frame) conversion with spatial downsampling and frame-rate reduction in a CPU and memory efficient manner, while additionally minimizing picture quality degradation as measured by PSNR. This is the first algorithm to our knowledge that effectively uses both spatial and temporal downsampling in an MPEG-2 to H.263 field to frame transcoder in order to achieve substantial bitrate reduction. This paper discusses recoding experiments used to determine appropriate source and target coding parameters for the transcoder, provides a detailed description of the transcoding algorithm, and describes the performance of a software implementation of the transcoder.