cssi/SciSciGPT-SciSciNet huggingface dataset:
Supersymmetric Proca-Yang-Mills system

We determine the off-shell N = 1 supersymmetry transformation rules for a tensor-Yang-Mills system in which the tensor field transforms in a nontrivial representation of the Yang-Mills group, and there is an additional vector multiplet in the same represen- tation. We then show that this system describes a massive tensor multiplet coupled to Yang-Mills in which the additional vector multiplet is eaten by the tensor field. Next, we construct an action which consists of four separately off-shell supersymmetric pieces and find that integrating out the auxiliary fields gives rise to an infinite number of higher order couplings of the scalar field belonging to the tensor multiplet. We describe the dualization of the massive tensor to a massive vector, thereby ending up with an on-shell supersymmet- ric nonabelian massive vector multiplet coupled to an off-shell Yang-Mills multiplet which we refer to as the supersymmetric Proca-Yang-Mills system. This description of massive vectors is contrasted with the standard one obtained through the Higgs mechanism.
Investor Sentiment and Stock Market Liquidity

Recent research on liquidity has reported that aggregate liquidity in the stock market varies over time, and evidence suggests that this variation affects stock returns. Although the importance of market liquidity in asset pricing has been well documented, little is known about what causes stock market liquidity to vary over time. This paper examines whether the time-series variation in stock market liquidity is related to investor sentiment. Using the liquidity measure developed by Amihud [2002] and two survey-based investor sentiment indices, I find that the stock market is more liquid when sentiment indices rise, that is, when investors are more bullish. Moreover, the Granger causality tests suggest that investor sentiment Granger-causes market liquidity. Further analyses show that market trading volume also increases when investor sentiment is higher. In addition, the finding that the market is more liquid when investor sentiment is higher still persists even after controlling for the effect of market...
Brownian Shape Dynamics in Fission

Abstract Remarkably accurate fission-fragment mass distributions can be obtained by treating the nuclear shape evolution as a Metropolis walk on previously calculated five-dimensional potential-energy surfaces; this novel method is briefly reviewed here.
The X-Ray Spectra and Spectral Variability of Intermediate-Type Seyfert Galaxies: ASCA Observations of NGC 4388 and ESO 103-G35

The X-ray spectra of two intermediate-type Seyfert galaxies are investigated using ASCA observations separated by more than 1 yr. Both NGC 4388 and ESO 103-G35 exhibit strong, narrow Fe Kα line emission and absorption by cold neutral gas with a column density ~1023 cm-2, characteristic of the X-ray spectra of type 2 Seyfert galaxies. The power-law continuum flux has changed by a factor of 2 over a timescale of ~2 yr for both objects, declining in the case of NGC 4388 and rising in ESO 103-G35. No variation was observed in the equivalent width of the Fe Kα line in the spectra of NGC 4388, implying that the line flux declined with the continuum. We find that the strength of the line cannot be accounted for by fluorescence in line-of-sight material with the measured column density unless a "leaky-absorber" model of the type favored for IRAS 04575-7537 is employed. The equivalent width of the Fe Kα emission line is seen to decrease between the observations of ESO 103-G35 while the continuum flux increased. The 1996 observation of ESO 103-G35 can also be fitted with an absorption edge at 7.4 ± 0.2 keV due to partially ionized iron, and when an ionized absorber model is fitted to the data it is found that the equivalent column of neutral hydrogen rises to 3.5 × 1023 cm-2. The Fe Kα line flux can be accounted by fluorescence in this material alone, and this model is also a good representation of the 1988 and 1991 Ginga observations. There is then no requirement for a reflection component in the ASCA spectra of ESO 103-G35 or NGC 4388.
Photodissociation of Vinyl Bromide and the Heat of Formation of the Vinyl Radical

We have performed measurements of the translational energy distributions and anisotropy parameters of the photodissociation products of vinyl bromide at 193 nm. Br-atom and HBr elimination were observed with a branching ratio of 1.28 ± 0.05 between the two channels. Both processes occurred with a large release of translational energy, an average of about 2.0 eV for the Br-atom channel and somewhat less for HBr elimination. The maximum release of translational energy for Br + C2H3 formation led to an upper limit of 77 ± 3 kcal/mol to D0(C2H3-Br), from which an upper limit to the heat of formation of the vinyl radical, 71 ± 3 kcal/mol, was derived. This result was used to reexamine crossed molecular beams data relevant to the determination of the heat of formation of the vinyl radical. A metastable state of C2H3 observed in the photodissociation of vinyl bromide was interpreted as the formation of C2H3(A2A″).
Pericyclic reactions of cyclobutyne: An exception to orbital symmetry considerations

Abstract By using AM1 methodology to compute reaction paths, cyclobutyne is found to isomerize to 1,2,3-butatriene and to undergo [2+2] cycloaddition to ethylene. The stereochemistry of the ring-opening reaction and the identification of a concerted pathway for the cycloaddition are interpreted in terms of the theory of orbital isomerism.
Microfluidic Structured Illumination Microscopy

We apply the principle of structured illumination microscopy to a microfluidic device. Sample flow across a fixed illumination pattern resolves phase ambiguity. We demonstrate the technique experimentally by reconstructing superresolved images of yeast cells.
Space-time tradeoffs for linear recursion

A linear recursive procedure is one each of whose executions activates at most one invocation of itself. When linear recursion cannot be replaced by iteration, it is usually implemented with a stack of size proportional to the depth of recursion. In this paper we analyze implementations of linear recursion which permit large reductions in storage space at the expense of a small increase in computation time. For example, if the depth of recursion isn, storage space can be reduced to $$\sqrt n $$ at the cost of a constant factor increase in running time. The problem is treated by abstracting any implementation of linear recursion as the pebbling of a simple graph, and for this abstraction we exhibit the optimal space-time tradeoffs.
Expanding plasmas and quasinormal modes of anti-de Sitter black holes

We compute the gravitational quasinormal modes of the global AdS5-Schwarzschild solution. We show how to use the holographic dual of these modes to describe a thermal plasma of finite extent expanding in a slightly anisotropic fashion. We compare these flows with the behavior of quark-gluon plasmas produced in relativistic heavy ion collisions by estimating the elliptic flow coefficient and the thermalization time.
The robustness of optimal equilibrium among overlapping generations

We combine and strengthen optimality and robustness theorems for the overlapping-generations model of money. Roughly, we find a Pareto-optimal monetary equilibrium of a generic stationary economy that is near an optimal monetary equilibrium of each nearby non-stationary economy. Since the nearby equilibria are monetary, the general problem of macroeconomic stabilization reduces to maintaining the money supply. And since the nearby equilibria are optimal, stabilization is socially desirable.
On a Data-Driven Method for Staffing Large Call Centers

We consider a call center model with multiple customer classes and multiple server pools. Calls arrive randomly over time, and the instantaneous arrival rates are allowed to vary both temporally and stochastically in an arbitrary manner. The objective is to minimize the sum of personnel costs and expected abandonment penalties by selecting an appropriate staffing level for each server pool. We propose a simple and computationally tractable method for solving this problem that requires as input only a few system parameters and historical call arrival data for each customer class; in this sense the method is said to be data-driven. The efficacy of the proposed method is illustrated via numerical examples. An asymptotic analysis establishes that the prescribed staffing levels achieve near-optimal performance and characterizes the magnitude of the optimality gap.
Overinvestment and fraud

Abstract We analyze the interactions between two managerial tasks: investing and revealing information. We assume that a manager can invest influencing the firm’s quality, then he reports this quality to investors. Whenever truthful reporting is not an equilibrium, the manager has incentives to overinvest relative to shareholders. Therefore, the potential for market manipulation is the key in understanding investment policy; it is the desire to manipulate prices that leads to inefficient investment. Also, more manipulation occurs when the manager is in control, so prices are less informative. Finally, we show that the manager is better off with an exogenous reporting policy.
Mode Identification from Combination Frequency Amplitudes in ZZ Ceti Stars

The light curves of variable DA stars are usually multiperiodic and nonsinusoidal, so that their Fourier transforms show peaks at eigenfrequencies of the pulsation modes and at sums and differences of these frequencies. These combination frequencies provide extra information about the pulsations, both physical and geometrical, that is lost unless they are analyzed. Several theories provide a context for this analysis by predicting combination frequency amplitudes. In these theories, the combination frequencies arise from nonlinear mixing of oscillation modes in the outer layers of the white dwarf, so their analysis cannot yield direct information on the global structure of the star as eigenmodes provide. However, their sensitivity to mode geometry does make them a useful tool for identifying the spherical degree of the modes that mix to produce them. In this paper we analyze data from eight hot, low-amplitude DAV white dwarfs and measure the amplitudes of combination frequencies present. By comparing these amplitudes to the predictions of the theory of Goldreich & Wu, we have verified that the theory is crudely consistent with the measurements. We have also investigated to what extent the combination frequencies can be used to measure the spherical degree (?) of the modes that produce them. We find that modes with ? > 2 are easily identifiable as high ? based on their combination frequencies alone. Distinguishing between ? = 1 and 2 is also possible using harmonics. These results will be useful for conducting seismological analysis of large ensembles of ZZ Ceti stars, such as those being discovered using the Sloan Digital Sky Survey. Because this method relies only on photometry at optical wavelengths, it can be applied to faint stars using 4 m class telescopes.
Palladium-catalyzed enantioselective addition of two distinct nucleophiles across alkenes capable of quinone methide formation

A sequential intramolecular−intermolecular enantioselective alkene difunctionalization reaction has been developed which is thought to proceed through Pd-catalyzed quinone methide formation. The synthesis of new chiral heterocyclic compounds with adjacent chiral centers is achieved in enantiomeric ratios up to 99:1 and diastereomeric ratios up to 10:1.
On adaptive time stepping approaches for thermal solidification processes

Thermal solidification processes are an important concern in today’s manufacturing technology. Because of the complex geometric nature of real‐world problems, analytical techniques with closed‐form solutions are scarce and/or not feasible. As a consequence, various numerical techniques have been employed for the numerical simulations. Of interest in the present paper are thermal solidification problems involving single or multiple arbitary phases. In order to effectively handle such problems, the finite element method is employed in conjunction with adaptive time stepping approaches to accurately and effectively track the various phase fronts and describe the physics of phase front interactions and thermal behaviour. In conjunction with the enthalpy method which is employed to handle the latent heat release, a fixed‐grid finite element technique and an automatic time stepping approach which uses the norm of the temperature distribution differences between adjacent time step levels to control the error are...
Silicon Mach-Zehnder waveguide interferometers operating at 1.3 μm

Mach-Zehnder waveguide interferometers have been fabricated in silicon and operation has been demonstrated at λ = 1.3 μm. The switching mechanism is based on the thermally induced variation of the refractive index of crystalline silicon. Modulation depths of 40% were obtained for switching powers of 30 mW and switching times of 50 μs.
VOLUMES OF RESTRICTED MINKOWSKI SUMS AND THE FREE ANALOGUE OF THE ENTROPY POWER INEQUALITY

In noncommutative probability theory independence can be based on free products instead of tensor products. This yields a highly noncommutative theory: free probability theory (for an introduction see [9]). The analogue of entropy in the free context was introduced by the second named author in [8]. Here we show that Shannon's entropy power inequality ([6, 1]) has an analogue for the free entropy χ(X) (Theorem 2.1). The free entropy, consistent with Boltzmann's formulaS=klogW, was defined via volumes of matricial microstates. Proving the free entropy power inequality naturally becomes a geometric question. Restricting the Minkowski sum of two sets means to specify the set of pairs of points which will be added. The relevant inequality, which holds when the set of addable points is sufficiently large, differs from the Brunn-Minkowski inequality by having the exponent 1/n replaced by 2/n. Its proof uses the rearrangement inequality of Brascamp-Lieb-Luttinger ([2]). Besides the free entropy power inequality, note that the inequality for restricted Minkowski sums may also underlie the classical Shannon entropy power inequality (see 3.2 below).
Synthesis and Characterization of the "Metallic Salts" A5Pn4 (A = K, Rb, Cs and Pn = As, Sb, Bi) with Isolated Zigzag Tetramers of Pn44- and an Extra Delocalized Electron

The isostructural title compounds were prepared by direct reactions of the corresponding elements, and their structures were determined from single-crystal X-ray diffraction data in the monoclinic space group C2/m, Z = 2 (K5As4, a = 11.592(2) A, b = 5.2114(5) A, c = 10.383(3) A, beta = 113.42(1) degrees; K5Sb4, a = 12.319(1) A, b = 5.4866(4) A, c = 11.258(1) A, beta = 112.27(7) degrees; Rb5Sb4, a = 12.7803(9) A, b = 5.7518(4) A, c = 11.6310(8) A, beta = 113.701(1) degrees; K5Bi4, a = 12.517(2) A, b = 5.541(1) A, c = 11.625(2) A, beta = 111.46(1) degrees; Rb5Bi4, a = 12.945(4) A, b = 5.7851(9) A, c = 12.018(5) A, beta = 112.78(3) degrees; Cs5Bi4, a = 12.887(3) A, b = 6.323(1) A, c = 12.636(1) A, beta = 122.94(2) degrees). The compounds contain isolated and flat zigzag tetramers of Pn4(4-) (Pnictide (Pn) = As, Sb, Bi) with a conjugated pi-electron system of delocalized electrons. All six compounds are metallic ("metallic salts") and show temperature-independent (Pauli-like) paramagnetism due to a delocalized electron from the extra alkali-metal cation in the formula. At low temperatures (around 9.5 K) and low magnetic fields the bismuthides become superconducting.
STRUCTURAL AND PHOTOMETRIC CLASSIFICATION OF GALAXIES. I. CALIBRATION BASED ON A NEARBY GALAXY SAMPLE

In this paper we define an observationally robust, multiparameter space for the classification of nearby and distant galaxies. The parameters include luminosity, color, and the image-structure parameters: size, image concentration, asymmetry, and surface brightness. Based on an initial calibration of this parameter space using the normal Hubble types surveyed in 1996 by Frei et al., we find that only a subset of the parameters provide useful classification boundaries for this sample. Interestingly, this subset does not include distance-dependent scale parameters such as size or luminosity. The essential ingredient is the combination of a spectral index (e.g., color) with parameters of image structure and scale: concentration, asymmetry, and surface brightness. We refer to the image structure parameters (concentration and asymmetry) as indices of form. We define a preliminary classification based on spectral index, form, and surface brightness (a scale) that successfully separates normal galaxies into three classes. We intentionally identify these classes with the familiar labels of early, intermediate, and late. This classification, or others based on the above four parameters, can be used reliably to define comparable samples over a broad range in redshift. The size and luminosity distribution of such samples will not be biased by this selection process except through astrophysical correlations between spectral index, form, and surface brightness.
The diffractive structure function at the Tevatron: CDF results

Abstract Results on hard diffraction from CDF are reviewed with emphasis on the determination of the diffractive structure function of the (anti)proton from single diffractive and double Pomeron exchange dijet production. Comparison of the diffractive dijet results with predictions based on diffractive deep inelastic scattering at HERA shows a breakdown of conventional QCD factorization. A similar breakdown is observed within the CDF results in comparing the structure functions obtained from single diffraction and double Pomeron exchange.
The Electric and Magnetic Dipole Moments of the Neutron

In 1950 Purcell and Ramsey1 pointed out that the parity arguments then used to prove that particles and nuclei could not have electric dipole moments, must be based on an experimental rather than a theoretical basis. As a test of this assumption, Smith, Purcell and Ramsey2 used a neutron beam magnetic resonance apparatus to search for a neutron electric dipole moment and concluded that such a moment divided by the proton charge (µe/e) was experimentally less than 5 x 10−20 cm. Later, from the work of Lee and Yang3 and Wu, et al,4 it became apparent that the parity assumption was indeed invalid, but Landau5 and others pointed out that the parity argument against an electric dipole moment could be replaced by one based on time reversal invariance. However, Ramsey6 emphasized that time reversal invariance like parity at an earlier time, was merely assumed and must rest on an experimental basis. In 1964 Christenson, Cronin, Fitch, and Turlay7 discovered the CP violating mode in the decay of the KO L meson into two charged pions, which strongly suggested a violation of time reversal symmetry.
Role of photoproduction in exotic meson searches

Abstract We discuss two production mechanisms of the J PC =1 −+ exotic meson, hadroproduction, using pion beams and photoproduction. We show that the ratio of exotic to nonexotic, in particular the a 2 , meson-production cross sections is expected to be by a factor of 5 to 10 larger, in photoproduction then in hadroproduction. Furthermore we show that the low- t photoproduction of exotic meson is enhanced as compared to hadronic production. This findings support the simple quark picture in which exotic meson production is predicted to be enhanced when the beam is a virtual Q Q pair with a spin-1 (photon) rather then with a spin-0 (pion).
An application of combining results from multiple methods?statistical evaluation of uncertainty for NIST SRM 1508a

NIST standard reference materials (SRMs) are certified reference materials that are developed at NIST and provided to laboratories (industry, government and academia) for assessment and improvement of measurement quality. This paper details the statistical analysis related to the recertification of SRM 1508a, benzoylecgonine (cocaine metabolite) in freeze-dried urine, to incorporate new data. The recertification is based on combining measurement results from different measurement methods and time periods. Several different statistical models and corresponding estimators were considered for the certified value, its standard uncertainty and its expanded uncertainty.
An Iterative Method for the Synthesis of Symmetric Polyynes

An iterative synthetic route for obtaining symmetric polyynes was developed, consisting of a series of iodination and Stille coupling reactions. The starting materials employed in this pathway are simple and can be prepared easily. Polyynes containing up to seven C≡C bonds were synthesized using this method. This route is particularly effective for accessing polyynes with an odd number of C≡C bonds and has allowed for the synthesis of a new iodine-capped polyyne, diiododecapentayne.
Semi-supervised Learning for Opinion Detection

Research on opinion detection has shown that a large number of opinion-labeled data are necessary for capturing subtle opinions. However, opinion-labeled data, especially at the sub-document level, are often limited. This paper describes the application of Semi-Supervised Learning (SSL) to automatically produce more labeled data and explores the potential of SSL to improve transfer of labeled data to new domains. Preliminary results show that SSL performance is very close to a supervised system trained on the full data set and improves performance on out-of-domain data.
Architecture, Aesthetics and Pluralism: Theories of Taste as a Determinant of Architectural Standards

The description of America as a melting pot society has proven over the past twenty years to be quite inaccurate. While the slow and often arduous trek from Ellis Island to suburbia diluted specific ethnic characteristics and customs, it did not erase them. America has remained a pluralistic society and, in fact, has become more so with the increase in ethnic pride and the interest in family background symbolized by the popularity of Alex Haley's Roots. Any aspirant to a major political office will testify to the breadth of the constituency which must be appealed to in order to successfully campaign for election. To the satisfaction of big business, market analysts can demonstrate that products designed for specific markets can be far more profitable than assuming that society is a grey and undifferentiated mass. A corollary can be found in the arts and architecture where one finds a wide variety in form, style, and artistic intention. In architecture, for instance, the Modern Movement, which once held the promise of an industrial and humanistic revolution concretized in built form, has, upon retrospect, emerged as only the more successful from among a number of movements, all of which occurred during the first quarter of the twentieth century. The clear vision of the prophets of modernism, LeCorbusier, Gropius, and Mies Van der Rohe, can now barely be seen over the visual clutter of the urban landscape where new fashions in architecture have changed nearly as rapidly as those in clothing. In the end, the Modern Movement in architecture, like so many other movements throughout history, left only a few monuments.
Synthesis of The Mono-Cysteine Disulfide of Meso-2,3-Dimercaptosuccinic Acid

Abstract A synthesis of the title compound from dimethyl meso-2,3-dimercapto-succinate and a protected, activated cysteine derivative is described.
Flank Wear of Edge-Radiused Cutting Tools Under Ideal Straight-Edged Orthogonal Conditions

Understanding the effects of tool wear is critical to predicting tool life, the point at which tool performance, in terms of power requirement, dimensional error, surface finish, burring, or chatter, is no longer acceptable. To achieve the long cuts that are required for wear testing while maintaining a clear view of the basic process geometry effects, ideal straight-edged orthogonal conditions are realized in a bar-turning arrangement by employing a specially designed two-tool setup. The data show that increasing edge radius tends to increase wear rate, especially at the initial cut-in wear phase. The data also show that when the uncut chip thickness is less than or equal to the edge radius, forces actually decrease substantially with flank wear until most of the edge radius has been worn away. At that point the forces begin to increase with flank wear in a power-law fashion. This decreasing-then-increasing trend is a result of the parasitic (non chip removing) wear-land force increasing more slowly than the chip-removal force is decreasing. The decrease in chip-removal force with an increase in flank wear results from the blunt edge being effectively sharpened as it is removed by the growing wear land. An empirical model structure is formulated, guided by specific elements of the data, to well represent the force trends with respect to wear and edge radius and to assist in their interpretation. The edge-sharpening concept is further supported by a special experiment in which the edge sharpening effect is studied in the absence of wear land.
Anti-Markovnikov N−H and O−H Additions to Electron-Deficient Olefins Catalyzed by Well-Defined Cu(I) Anilido, Ethoxide, and Phenoxide Systems

The monomeric Cu(I) complexes (IPr)Cu(Z) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, Z = NHPh, OEt, or OPh) react with YH (Y = PhNH, PhCH2NH, EtO, or PhO) to catalytically add Y−H bonds across the CC bond of electron-deficient olefins to yield anti-Markovnikov organic products. Catalytic activity has been observed for olefins CH2C(H)(X) with X = CN, C(O)Me, or CO2Me as well as crotononitrile. Preliminary studies implicate an intermediate in which the C−Y bond forms through a nucleophilic addition pathway.
Arithmetic of Calabi-Yau varieties and rational conformal field theory

Abstract It is proposed that certain techniques from arithmetic algebraic geometry provide a framework which is useful to formulate a direct and intrinsic link between the geometry of Calabi–Yau manifolds and the underlying conformal field theory. Specifically, it is pointed out how the algebraic number field determined by the fusion rules of the conformal field theory can be derived from the number theoretic structure of the cohomological Hasse–Weil L -function determined by Artin’s congruent zeta function of the algebraic variety. In this context, a natural number theoretic characterization arises for the quantum dimensions in this geometrically determined algebraic number field.
The Mass Function

We present the mass functions for different mass estimators for a range of cosmological models. We pay particular attention to how universal the mass function is, and how it depends on the cosmology, halo identification, and mass estimator chosen. We investigate quantitatively how well we can relate observed masses to theoretical mass functions.
Liquid flow through an array-based chemical sensing system

A micromachined fluidic sensor array for the rapid characterization of multiple analytes in solution has been developed. A simple micromachined fluidic structure for this biological and chemical agent detection system has been designed and fabricated, and the system has been tested. Sensing occurs via optical changes to indicator molecules that are attached to polymeric microspheres (beads). A separate charged-coupled- device (CCD) is used for the simultaneous acquisition of the optical data from the selectively arranged beads in micromachined etch cavities. The micromachined bead support structure has been designed to be compatible wit this hybrid optical detection system. The structure consists of four layers: cover glass, micromachined silicon, dry film photoresist, and glass substrate. The bottom three layers are fabricated first, and the beads are selectively placed into micromachined etch cavities. Finally, the cover glass is applied to confine the beads. This structure utilizes a hydrophilic surface of the cover glass to draw a liquid sample into the sensor array without moving components, producing a compact, reliable, and potentially low-cost device. We have initially characterized fluid flow through a complete chip, showing complete filling of the sample chamber in approximately 2 seconds. The test results show that this system may be useful in micro total analysis systems ((mu) - TAS), especially in single-use biomedical applications.
Charge transfer to the ionosphere and to the ground during thunderstorms

[1] This study examines the current that is driven to the ionosphere and to the ground before, during and after single negative cloud-to-ground (CG) and intracloud (IC) lightning discharges. A numerical model has been developed, that calculates the quasi-electrostatic field before the lightning, due to the slow accumulation of the charge in the thundercloud, and after the lightning by taking into account the Maxwellian relaxation of charges in conducting atmosphere and accounting for the dissipation stage of the thunderstorm development. From these results, the charges that are transferred to the ionosphere and to the ground are calculated. We demonstrate the significance of considering the pre-lightning and the dissipation stages and accounting for realistic distribution of the conductivity inside of the thundercloud for the accurate calculation of the charge flow to the ionosphere and to the ground. We show that the charge transfer to the ionosphere depends mainly on the altitudes of the charges inside of the thundercloud and on their spatial separation. The amount of charge that is transferred to the ground, due to currents flowing in the vicinity of the thundercloud during a transient time period following a lightning discharge, is significantly affected by the conductivity distribution in the thundercloud and can be several times smaller than the amount of charge that is transferred to the ionosphere during the same time period.
Age structure of refractory interstellar dust and isotopic consequences

A sputtering and recycling Monte Carlo model, developed by Liffman and Clayton (1988) is used to calculate the distribution of existence times of the matter in interstellar dust composed of refractory metals. The mean age of each dust particle is defined not as the time it has existed but rather as the mass-weighted existence times of its parts at t = 6 Gyr of the modeled solar system formation. It is shown that Galactic evolution generates a mean correlation, applying to large numbers of particles binned according to size rather than according to individual particles, whose mean ages fluctuate statistically. The cosmochemical consequence is that if interstellar particles can be dynamically sorted into separate size populations during the aggregation history of solar system bodies, the collections of larger grains will constitute matter that is chemically older than collections of smaller grains. The macroscopic age difference generates isotopic anomalies by virtue of the time dependence of the secondary/primary nucleosynthesis yields. Results are compared with three different prescriptions for the sputtering of interstellar dust.
Integral Equations in the Study of Polar and Ionic Interaction Site Fluids

We consider some of the current integral equation approaches and application to model polar liquid mixtures. We show the use of multidimensional integral equations and in particular progress on the theory and applications of three dimensional integral equations. The IEs we consider may be derived from equilibrium statistical mechanical expressions incorporating a classical Hamiltonian description of the system. We give example including salt solutions, inhomogeneous solutions and systems including proteins and nucleic acids.
1.25-MHz attenuation measurement system

A system has been developed to make highly accurate measurements of nominally 6-dB increments of attenuation at 1.25 MHz. Initial experiments indicate a typical systematic error of 5 μB (1 μB = 0.00001 dB) with a resolution of 1 μB. A special linearity measurement system (LMS) using NBS-constructed linear tuned hybrids and power detectors has been used to determine the nonlinearity of a tuned 1.25-MHz power detector. This detector utilizes a single thermistor bead design with thermal isolation to obtain nearly linear tracking of a 4:1 change in input power. The nonlinear correction for this change, determined by the LMS, is on the order of 13 μB for the detector presently in use. This calibrated detector and another of similar design are used in the attenuation measurement system (AMS) to make power ratio measurements to determine the change in attenuation of the device under test (DUT). It is anticipated that changes of approximately 6 dB can be measured with initial insertion loss of up to 100 dB with an accuracy of 0.001 dB. A special design consideration will be required for units used for calibration in order to keep mismatch errors from significantly degrading the accuracies estimated above.
Demand for Customized Products, Production Flexibility, and Price Competition

In diesem Beitrag werden Markte untersucht, auf denen zusatzlich zur Produktion von Standardprodukten die Herstellung von Spezialprodukten in grosen Stuckzahlen („mass customization“) technologisch moglich ist. Es wird eine Situation verglichen, in der ein Monopolist sowohl Standard- als auch Spezialprodukte anbietet mit einer Situation, in der der eintretende Konkurrent den Markt fur Spezialprodukte bedient. Der Vergleich zeigt, das der Kundengeschmack die soziale Wunschbarkeit des Eintritts beeinflust. Fur den Eintretenden ist es unerheblich wie sich seine Spezialprodukte auf den Hauptproduktmarkt des eingesessenen Unternehmens auswirken und in manchen Fallen kann es dazu kommen, das er mehr Spezialprodukte anbietet als gesellschaftlich wunschbar. Im Gegensatz zur bisherigen Literatur wird gezeigt, das zunehmende Variabilitat der Nachfrage zu einer Verringerung von Investitionen in flexible Fertigungstechnologien fuhren kann.
The Luminosity Function of Nearby Galaxy Clusters. II. Redshifts and Luminosity Function for Galaxies in the Region of the Centaurus Cluster

We acquired spectra for a random sample of galaxies within a 0.83 deg2 region centered on the core of the Centaurus Cluster. Radial velocities were obtained for 225 galaxies to limiting magnitudes of V -17.0 are considered dwarfs. We constructed the cluster galaxy luminosity function (LF) by using these spectroscopic results to calculate the expected fraction of cluster members in each magnitude bin. The faint-end slope of the LF using this method is shallower than the one obtained using a statistical method to correct for background galaxy contamination. We also use the spectroscopy results to define surface brightness criteria to establish membership for the full sample. Using these criteria, we find a LF very similar to the one constructed with the statistical background correction. For both, we find a faint-end slope α ~ -1.4. The error in faint-end slope for the statistically corrected LF is ~±0.2. Adjusting the surface brightness membership criteria, we find that the data are consistent with a faint-end slope as shallow as -1.22 or as steep as -1.50. We describe in this paper some of the limitations of using these methods for constructing the galaxy LF. This is Paper II in our investigation of the cluster galaxy LF.
The complexity of finding independent sets in bounded degree (hyper)graphs of low chromatic number

We prove almost tight hardness results under randomized reductions for finding independent sets in bounded degree graphs and hypergraphs that admit a good coloring. Our specific results include the following (where Δ, a constant, is a bound on the degree, and n is the number of vertices):• NP-hardness of finding an independent set of size larger than O (n[EQUATION]) in a 2-colorable r-uniform hypergraph for each fixed r ≥ 4. A simple algorithm is known to find independent sets of size Ω ([EQUATION]) in any r-uniform hypergraph of maximum degree Δ. Under a combinatorial conjecture on hypergraphs, the (log Δ)1/(r−1) factor in our result is necessary.• Conditional hardness of finding an independent set with more than O ([EQUATION]) vertices in a k-colorable (with k ≥ 7) graph for some absolute constant c ≤ 4, under Khot's 2-to-1 Conjecture. This suggests the near-optimality of Karger, Motwani and Sudan's graph coloring algorithm which finds an independent set of size Ω ([EQUATION]) in k-colorable graphs.• Conditional hardness of finding independent sets of size nΔ-1/8+oΔ(1) in almost 2-colorable 3-uniform hypergraphs, under Khot's Unique Games Conjecture. This suggests the optimality of the known algorithms to find an independent set of size Ω(nΔ-1/8) in 2-colorable 3-uniform hypergraphs.• Conditional hardness of finding an independent set of size more than O(nΔ -1/r-1 log -1/r-1 Δ) in r-uniform hypergraphs that contain an independent set of size n(1 − O(log r/r)) assuming the Unique Games Conjecture.
Screening Soybean Genotypes for Drought and Heat Tolerance

Several soybean [Glycine max (L.) Merr.] germplasms from maturity groups III through VII were evaluated at three osmotic potential levels (-0.017, 0.3 and -0.5 MPa) using polyethylene glycol M.W. 8000 and four temperature regimes (10, 25, 50 and 110°C) for drought and heat tolerance, respectively. Heat injury varied significantly among growth stages with the highest heat injury occurring at the flowering stage. Susceptibility to heat injury decreased toward maturity with the exception of a few genotypes. Genotypic variability was found among the lines in both drought and heat tolerance tests. This study identified the lines PI 408.155, PI 423.827B, PI 423.759 and Pershing as both drought and heat tolerant. In general, the larger-seeded lines failed to germinate at -0.50 MPa. A positive and significant relationship between promptness index and germina-tion stress index was found. However, no significant correlation was observed between germination stress index and the heat tolerance test. Based on the results from the germination test, lines PI 393.550, PI393.547, PI 86.103, PI 171.437, PI 86.490 and PI 423.852 had high germination stress indices and need further testing for heat stress tolerance.
A Multidisciplinary Approach to an Ethic of Biodefense and Bioterrorism

The normative approach to defining an ethic of a field, which focuses on one disciplinary field, requires modification in the consideration of a biodefense ethic to include not one discipline, but many. The consideration of an ethic in biodefense must capture issues in a multidisciplinary scope, including the ethical studies in the disciplines of medicine, sciences, technology, law, international relations, public health, environment, and war, each having their unique framework of ethical constructs. An ethic of bioterrorism and biodefense raises issues which can be examined utilizing multidisciplinary ethical considerations. The disciplines of medicine, sciences, technology, law, international relations, public health, environment, and war each have a framework of ethical principles which are essential in the scope of ethics which are incident to bioterrorism and biodefense; the absence of any one of which would create a void in our understanding of the complexity of this subject.
A concise synthesis of a benzimidazole analogue of mycophenolic acid using a BF3-Et2O catalyzed amino-claisen rearrangement.

Abstract A nine-step synthesis of the benzimidazole analogue, 2 , of mycophenolic acid is reported involving both the BF 3 -Et 2 O catalysed aromatic amino- and the ortho ester Claisen rearrangements as key steps.
Top Quark Physics at the Tevatron

The authors review the analyses of t{bar t} candidate events in various decay channels, carried out using the p{bar p} collider data at {radical}s = 1.8 TeV by the CDF and D0 collaborations at the Fermilab Tevatron. The measurements of the top quark mass (m{sub t}) using lepton+jets channel yield m{sub t} = 173.3 {+-} 7.8 GeV/c{sup 2} from D0 analysis and m{sub t} = 175.9 {+-} 6.9 GeV/c{sup 2} from CDF analysis. The production cross section is measured to be {sigma}{sub t{bar t}} = 7.6{sub -1.5}{sup +1.8} pb by CDF and {sigma}{sub t{bar t}} = 5.6 {+-} 1.8 pb by D0. Further investigations using t{bar t} decays and future prospects are briefly discussed.
Differential regulation of the SMN2 gene by individual HDAC proteins

Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder that is the leading genetic cause of infantile death. SMA is caused by homozygous deletion or mutation of the survival of motor neuron 1 gene (SMN1). The SMN2 gene is nearly identical to SMN1, however is alternatively spliced. The close relationship to SMN1 results in SMN2 being a very power genetic modifier of SMA disease severity and a target for therapies. We sought to identify the regulatory role individual HDAC proteins use to control expression of full length protein from the SMN2 genes. We used quantitative PCR to determine the effects shRNA silencing of individual HDACs on the steady state levels of a SMN2-luciferase reporter transcripts. We determined that reduction of individual HDAC proteins was sufficient to increase SMN protein levels in a transgenic reporter system. Knockdown of class I HDAC proteins preferentially activated the reporter by increased promoter transcription. Silencing of class II HDAC proteins maintained transcriptional activity; however silencing of HDAC 5 and 6 also appeared to enhance inclusion of an alternatively spliced exon. This work highlights HDAC proteins 2 and 6 as excellent investigative targets. These data are important to the basic understanding of SMN expression regulation and the refinements of current therapeutic compounds as well as the development of novel SMA therapeutics.
A Dynamic and Semantically-Aware Technique for Document Clustering in Biomedical Literature

As an unsupervised learning process, document clustering has been used to improve information retrieval performance by grouping similar documents and to help text mining approaches by providing a high-quality input for them. In this article, the authors propose a novel hybrid clustering technique that incorporates semantic smoothing of document models into a neural network framework. Recently, it has been reported that the semantic smoothing model enhances the retrieval quality in Information Retrieval (IR). Inspired by that, the authors developed and applied a context-sensitive semantic smoothing model to boost accuracy of clustering that is generated by a dynamic growing cell structure algorithm, a variation of the neural network technique. They evaluated the proposed technique on biomedical article sets from MEDLINE, the largest biomedical digital library in the world. Their experimental evaluations show that the proposed algorithm significantly improves the clustering quality over the traditional clustering techniques including k-means and self-organizing map (SOM).
Revitalizing public management training in the Americas

The decade of the 1980s signalled major changes within public administration and development-oriented activities. As a consequence of the internationalization of the agendas of practitioners and academics working in these areas, there is today a growing convergence among public policy, public management, public administration and political science. Given the complexity of the public sector cross-nationally, what has become necessary in public management education is the design of programmes that meet specific needs and priorities and which are responsive to very different national settings. This particular case study is centred around one endeavour to achieve more effective interfacing between theory and practice, in the teaching of public management and the design of development programmes in the United States (US). It is based on an assessment of a 10-year co-operative endeavour between the National Association of Schools of Public Affairs and Administration and the US Agency for International Development. The outcomes of this project provided not only leverage for important changes in the teaching programmes of schools concerned with international management education but also built a new relationship between government and a non-governmental organization through the contacting out of management development work.
Lease Pricing for Farm Real Estate

A lease pricing model for farm land is developed that is consistent with traditional leasing principles and allows greater flexibility in determining crop share levels either separately or in combination with a fixed cash payment. The share levels are linked to the farm's soil productivity, the costs of each party's resource contributions, and their respective cost structures. The resulting menu of lease prices can enhance the equitability of leasing contracts, expand the range of contract choices, promote mutual incentives for the leasing parties, and heighten the efficiency of leasing markets through greater standardization of leases. Farmers long have used leasing to finance the control of farm land under either share rent or cash rent arrangements. Nationwide, about 43% of U.S. farm land is operated under a leasing contract. Illinois, in particular, has the highest incidence of both farm real estate leasing and share leasing contracts in the United
Airfoil pressure measurements during oblique shock-wave/vortex interaction in a Mach 3 stream

An experimental investigation of the interaction between streamwise discrete vortices and oblique shocks formed over a two-dimensional wedge surface was conducted in a Mach 3 blowdown wind tunnel. An instrumented two-dimensional wedge was placed downstream of a semiispan wing so that the trailing tip vortex would arbitrarily interact with the shock wave formed over the wedge surface. The experiments were designed to simulate interaction of streamwise vortices from upstream bodies with shock waves formed over aft surfaces as might be encountered in supersonic flight of aircraft and missiles. The influence of vortex strength and vortex-airfoil vertical separation distance on the interaction was examined.
Algebraic and hamiltonian approaches to isostokes deformations

We study a generalization of the isomonodromic deformation to the case of connections with irregular singularities. We call this generalization Isostokes Deformation. A new deformation parameter arises: one can deform the formal normal forms of connections at irregular points. We study this part of the deformation, giving an algebraic description. Then we show how to use loop groups and hypercohomology to write explicit hamiltonians. We work on an arbitrary complete algebraic curve, the structure group is an arbitrary semisimple group.