cssi/SciSciGPT-SciSciNet huggingface dataset:
Large eddy simulations of 2-D and 3-D spatially developing mixing layers

A complete understanding of the noise generation mechanisms is prerequisite to reducing aircraft jet noise. A computationally intensive large eddy simulation (LES) can directly predict the noise. For this purpose, the Ansys-Fluent LES tool is evaluated for its modeling accuracy by studying a canonical problem. A mixing layer at a Reynolds number of 720 is simulated using LES in two- and three-dimensions without the splitter plate walls and is studied extensively to gain insights of the flow physics. The effects of inflow forcing and the buffer zone at the domain exit incorporated in 2-D LES are investigated. The primary and secondary instabilities of the 2-D mixing layer are captured well using random inflow forcing. The buffer zone is found to help the prediction of the Reynolds stresses near the exit boundary. The sensitivity of the 2-D results to time-step, sampling time and grid is also studied. The 2-D grid is optimized before constructing a mesh for 3-D LES. An improved vortex method (VM) algorithm, implemented for inflow forcing in 3-D, is found to capture the translative instability and the stream-wise vortices of the mixing layer. The energy spectrum of the LES computations indicate that the second-order-accurate bounded central differencing scheme of Ansys-Fluent, used in the present study, is adequate for simulating turbulent flows.
Do volatility determinants vary across futures contracts? Insights from a smoothed Bayesian estimator

We apply a new Bayesian approach to multiple-contract futures data. It allows the volatility of futures prices to depend upon physical inventories and the contract's time to delivery—and it allows those parametric effects to vary over time. We investigate price movements for lumber contracts over a 13-year period and find a time-varying negative relationship between lumber inventories and lumber futures price volatility. The Bayesian approach leads to different conclusions regarding the size of the inventory effect than does the standard method of parametric restrictions across contracts. The inventory effect is smaller for the most recent contracts when the inventory levels are larger. In contrast, the Bayesian approach does not lead to substantively different conclusions about the time-to-delivery effect than do traditional classical methods. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:257–277, 2010
Time-Resolved Raman Scattering and Transmission Measurements During Pulsed Laser Annealing

Raman Scattering from a 7 nsec pulsed dye laser has been used to determine the onset of recrystallization following an 8 nsec dye laser excitation pulse in ion-implanted silicon. We find essentially complete recrystallization 59 nsec after the first excitation pulse and from Stokes-anti-Stokes ratios we find at 59 nsec a crystalline lattice temperature of 600 ± 200° C. Time-resolved transmission measurements at λ = 1.15 µm also demonstrate that no molten phase has occurred even though the usual reflectivity enhancement is observed.
Dark matter halo abundances, clustering and assembly histories at high redshift

We use a suite of high-resolution N-body simulations to study the properties, abundance and clustering of high-mass haloes at high redshift, including their mass assembly histories and mergers. We find that the analytic form which best fits the abundance of haloes depends sensitively on the assumed definition of halo mass, with common definitions of halo mass differing by a factor of 2 for these low-concentration, massive haloes. A significant number of massive haloes are undergoing rapid mass accretion, with major merger activity being common. We compare the mergers and mass accretion histories to the extended Press–Schechter formalism. We consider how major merger induced star formation or black hole accretion may change the distribution of photon production from collapsed haloes, and hence reionization, using some simplified examples. In all of these, the photon distribution for a halo of a given mass acquires a large scatter. If rare, high-mass haloes contribute significantly to the photon-production rates, the scatter in photon-production rate can translate into additional scatter in the sizes of ionized bubbles.
Examining the Efficacy of a Tier 2 Kindergarten Mathematics Intervention

This study examined the efficacy of a Tier 2 kindergarten mathematics intervention program, ROOTS, focused on developing whole number understanding for students at risk in mathematics. A total of 29 classrooms were randomly assigned to treatment (ROOTS) or control (standard district practices) conditions. Measures of mathematics achievement were collected at pretest and posttest. Treatment and control students did not differ on mathematics assessments at pretest. Gain scores of at-risk intervention students were significantly greater than those of control peers, and the gains of at-risk treatment students were greater than the gains of peers not at risk, effectively reducing the achievement gap. Implications for Tier 2 mathematics instruction in a response to intervention (RtI) model are discussed.
Intelligent Multiple-Criteria Broadcasting in Mobile Ad-hoc Networks

Networks often require a copy of a message to be delivered to every network node. The network-layer can provide this service, referred to as network-wide broadcast routing, or simply "broadcasting". Broadcasting has many applications, including its role as a building block in many routing protocols. In a MANET, simplistic broadcast schemes (such as flooding) inundate the network with redundancy, contention, collision, and energy-inefficiency. This can prevent broadcasts from achieving the objectives of optimal delivery ratio, energy balancing, and latency. As a solution, we propose Multiple-Criteria Broadcasting (MCB). In MCB, the source of each broadcast specifies the importance assigned to broadcast objectives. Network nodes use this policy, along with local and neighbor knowledge, to broadcast in accordance with the objective priorities attributed to the message. Using ns2, the performance of MCB is evaluated and compared to other broadcast protocols. To present knowledge, MCB constitutes the first reconfigurable, multi-objective approach to broadcasting.
Reliable before-fabrication forecasting of expected surface slope distributions for x-ray optics

Reliable before-fabrication forecasting of expected surface slope distributions for x-ray optics Yekaterina V. Yashchuk † and Valeriy V. Yashchuk* Lawrence Berkeley National Laboratory, Berkeley, California 94720 *Corresponding author: VVYashchuk@lbl.gov Currently at Esurance, Inc., San Francisco, California 94111
Comment on quark masses in SCET

Abstract Quark masses are included in the SCET Lagrangian. Treating the strange quark mass as order ΛQCD, we find that strange quark mass terms are suppressed in SCETI, but are leading order in SCETII. This is relevant for B decays to K ∗ and K. Strange quark mass effects in semileptonic and weak radiative form factors are studied. They give corrections to the form factors that are not suppressed by powers of the bottom quark mass, or, equivalently, by the large recoil energy of the final state meson, and preserve the heavy to light form factor relations that follow from using the leading order current.
Monte Carlo simulation of the classical two-dimensional one-component plasma

Monte Carlo simulation, lattice dynamics in the harmonic approximation, and solution of the hypernetted chain equation were used to study the classical two-dimensional one component plasma. The system consists of a single species of charged particles immersed in a uniform neutralizing background. The particles interact via a l/r potential, where r is the two dimensional separation. Equations of state were calculated for both the liquid and solid phases. Results of calculation of the thermodynamic functions and one and two particle correlation functions are presented.
Bounds on reachable sets using ordinary differential equations with linear programs embedded

Abstract This work considers the computation of time-varying enclosures of the reachable sets of nonlinear control systems via the solution of an initial value problem in ordinary differential equations (ODEs) with linear programs (LPs) embedded. To ensure the numerical tractability of such a formulation, the properties of the ODEs with LPs embedded are discussed including existence and uniqueness of the solutions of the initial value problem in ODEs with LPs embedded. This formulation is then applied to the computation of rigorous componentwise time-varying bounds on the states of a nonlinear control system. The bounding theory used in this work exploits physical information to yield tight bounds on the states; this work develops a new implementation of this theory. Finally, the tightness of the bounds are demonstrated for a model of a reacting chemical system with uncertain rate parameters.
An efficient asymmetric synthesis of trisubstituted cyclohexenones and trisubstituted cyclopentenones from chiral 2,2-dialkyl 1,4- and 1,5-diketones

Abstract Addition of organolithium reagents to the chiral bicyclic lactams 2 and 9 leads to the title compounds in high enantioselectivity.
Optically induced homogeneous line narrowing

The ${R}_{1}$ dephasing time in ruby (0.05 wt.% ${\mathrm{Cr}}_{2}$${\mathrm{O}}_{3}$) is observed to increase by an order of magnitude when selected transitions of the ${R}_{2}$ line are pumped. Spin flip-flop dephasing in the ground state is suppressed by optically induced depopulation of the $^{4}A_{2}(\ifmmode\pm\else\textpm\fi{}\frac{1}{2})$ levels.
Approximate distributed Bellman-Ford algorithms

Routing algorithms based on the distributed Bellman-Ford algorithm (DBF) suffer from exponential message complexity in some scenarios. We propose two modifications to the algorithm which result in a polynomial message complexity without adversely affecting the response time of the algorithm. However, the new algorithms may not compute the shortest path. Instead, the paths computed can be worse than the shortest path by at most a constant factor ( >
Chandra Observation of the Merging Cluster A168: A Late Stage in the Evolution of a Cold Front

We present Chandra observations of the cool cluster A168, for which previous X-ray imaging and optical studies indicated a merger of two subclusters nearly in the plane of the sky. We derive a temperature map for A168, which shows that the merger has proceeded beyond the core passage and is near subcluster turnaround. It also reveals an unusual feature: the gas core of one of the subclusters forms a tonguelike structure extending ahead (in the direction of motion) of the subcluster center. The coolest cluster gas is found in a crescent-shaped region at the tip of this tongue and forms a cold front in pressure equilibrium with the external gas. In contrast with this feature's forward location, previously observed merger cold fronts (e.g., A3667, 1E 0657-56) lagged behind their host subclusters, as expected in the presence of ram pressure. We propose that A168 illustrates a much later stage in the evolution of a cold front, when its host subcluster approaches the apocenter of the merger orbit where the ram pressure on its gas drops sharply. As a result, a large chunk of the subcluster gas "slingshots" past the dark matter center, becomes unbound from the subcluster, and expands adiabatically, as seen in some recent hydrodynamic simulations.
Diastereoselective cyclopropanations of chiral bicyclic lactams leading to enantiomerically pure cyclopropanes. Application to the total synthesis of CIS-(1S, 3R)-deltamethrinic acid and R-(-)- dictyopterene C

Abstract A novel diastereoselective cyclopropanation based on readily available chiral bicylic lactams (1b-c, 6a-b) has provided a number of enantiomerically pure cyclopropanes. Cyclopropanations of unsaturated lactams (10a-h, 12-14) were performed using sulfur ylides as well as a 3+2 cycloaddition-photolysis sequence and furnished the desired cyclopropane adducts (16, 17, 19, 22) in fair to excellent yields. In all cases involving sulfur ylides, cyclopropanations proceeded with a high degree of exo/endo diastereoselectivity (>;90%). However, the mode of addition, exo vs endo, was found to be highly dependent on the angular substituent of the unsaturated lactam. In the case of diazoalkane cycloadditions, high regioselectivity was observed in all cases although exo/endo selectivity was governed by the diazoalkane employed. Diazoisopropane, being more reactive than diazomethane, normally led to lower diastereomeric ratios. Minor diastereomers could be readily removed by chromatography or in most cases by a single recrystallization to provide diastereomerically pure cyclopropyl bicyclic lactams (16, 17, 19, 22). Applications of this methodology to compounds of biological significance was exemplified by an asymmetric, total synthesis of cis-(1S, 3R)-deltamethrinic acid (34) and R-(-)- dictyopterene C' (42) in high enantiomeric purity.
Silicon Carbide Absorption Features: Dust Formation in the Outflows of Extreme Carbon Stars

Infrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 μm range, which has been tentatively attributed to silicon carbide (SiC). We add three new objects meeting these criterion to the seven previously known, bringing our total sample to ten sources. We also present the result of radiative transfer modeling for these stars, comparing these results with those of previous studies. In order to constrain model parameters, we use published mass-loss rates, expansion velocities, and theoretical dust condensation models to determine the dust condensation temperature. These show that the inner dust temperatures of the dust shells for these sources are significantly higher than previously assumed. This also implies that the dominant dust species should be graphite instead of amorphous carbon. In combination with the higher condensation temperature we show that this results in a much higher acceleration of the dust grains than would be expected from previous work. Our model results suggest that the very optically thick stage of evolution does not coincide with the timescales for the superwind, but rather, that this is a very short-lived phase. Additionally, we compare model and observational parameters in an attempt to find any correlations. Finally, we show that the spectrum of one source, IRAS 17534–3030, strongly implies that the 10-13 μm feature is due to a solid state rather than a molecular species.
An extension of quantitative nondivergence and applications to Diophantine exponents

We present a sharpening of nondivergence estimates for unipotent (or more gener- ally polynomial-like) flows on homogeneous spaces. Applied to metric Diophantine approxima- tion, it yields precise formulas for Diophantine exponents of affine subspaces ofR n and their nondegenerate submanifolds.
Loop series for discrete statistical models on graphs

In this paper we present the derivation details, logic, and motivation for the three loop calculus introduced in Chertkov and Chernyak (2006 Phys. Rev. E 73 065102(R)). Generating functions for each of the three interrelated discrete statistical models are expressed in terms of a finite series. The first term in the series corresponds to the Bethe–Peierls belief–propagation (BP) contribution; the other terms are labelled by loops on the factor graph. All loop contributions are simple rational functions of spin correlation functions calculated within the BP approach. We discuss two alternative derivations of the loop series. One approach implements a set of local auxiliary integrations over continuous fields with the BP contribution corresponding to an integrand saddle-point value. The integrals are replaced by sums in the complementary approach, briefly explained in Chertkov and Chernyak (2006 Phys. Rev. E 73 065102(R)). Local gauge symmetry transformations that clarify an important invariant feature of the BP solution are revealed in both approaches. The individual terms change under the gauge transformation while the partition function remains invariant. The requirement for all individual terms to be nonzero only for closed loops in the factor graph (as opposed to paths with loose ends) is equivalent to fixing the first term in the series to be exactly equal to the BP contribution. Further applications of the loop calculus to problems in statistical physics, computer and information sciences are discussed.
Binding in Charged Spherically Symmetric Objects

We consider the subject of self-binding in static, spherically symmetric objects consisting of a charged fluid. We have shown previously that in the case of a perfect fluid, only the localized part of the mass contributes to gravitational self-binding of such objects and that in the limiting case of objects comprised purely of electromagnetic mass, there is no gravitational binding. Here, we extend this result to the more general case of an anisotropic fluid. Our inspection of the Oppenheimer–Volkov equation allows tracking of both gravitational and non-gravitational contributions to binding of spherically symmetric objects and shows that those with pure electromagnetic mass cannot exist.
Molecular recognition in homogeneous transition metal catalysis: a biomimetic strategy for high selectivity

Traditional methods for selectivity control in homogeneous transition metal catalysis either employ steric effects in a binding pocket or chelate control. In a supramolecular strategy, encapsulation of the substrate can provide useful shape and size selectivity. A fully developed molecular recognition strategy involving hydrogen bonding or solvophobic forces has given almost completely regioselective functionalization of remote, unactivated C–H bonds.
BREAKING ALL THE RULES: THE COMPACT SYMMETRIC OBJECT 0402+379

We present results of multifrequency Very Long Baseline Array (VLBA) observations of the compact symmetric object (CSO) 0402+379. The parsec-scale morphology of 0402+379 allows us to confirm it as a CSO, while VLA data clearly show the presence of kiloparsec-scale structure. Thus, 0402+379 is only the second known CSO to possess large-scale structure. Another puzzling morphological characteristic found from our observations is the presence of two central, compact, flat-spectrum components, which we identify as possible active nuclei. We also present the discovery of neutral hydrogen absorption along the southern hot spot of 0402+379 with a central velocity ~1000 km s-1 greater than the systemic velocity. Multiepoch observations from the VLA archive, the Caltech-Jodrell Bank Survey, and the VLBA Calibrator Survey allow us to further analyze these anomalous features. Results of this analysis reveal significant motion in the northern hot spot, as well as appreciable variability in both of the core candidates. We consider the possibility that 0402+379 was formed during a recent merger. In this case, the two candidate cores could be interpreted as binary supermassive black holes that have not yet coalesced, whereas the large-scale radio emission could be attributed to interactions directly linked to the merger or to previous activity associated with one of the cores.
Scaling limit for the diffusion exit problem in the Levinson case

Abstract The exit problem for small perturbations of a dynamical system in a domain is considered. It is assumed that the unperturbed dynamical system and the domain satisfy the Levinson conditions. We assume that the random perturbation affects the driving vector field and the initial condition, and each of the components of the perturbation follows a scaling limit. We derive the joint scaling limit for the random exit time and exit point. We use this result to study the asymptotics of the exit time for 1D diffusions conditioned on rare events.
A DSM proof of surjectivity of monotone nonlinear mappings

A simple proof is given of a basic surjectivity result for monotone operators. The proof is based on the Dynamical Systems Method (DSM). MSC: 47A52
Measuring and evaluating maintenance process using reliability, risk, and test metrics

In analyzing the stability of a software maintenance process, it is important that it is not treated in isolation from the reliability and risk of deploying the software that result from applying the process. Furthermore, we need to consider the efficiency of the test effort that is a part of the process and a determinate of reliability and risk of deployment. The relationship between product quality and process capability and maturity has been recognized as a major issue in software engineering based on the premise that improvements in the process will lead to higher-quality products. To this end, we have been investigating an important facet of process capability-stability-as defined and evaluated by trend, change and shape metrics, across releases and within a release. Our integration of product and process measurement serves the dual purpose of using metrics to assess and predict reliability and risk and to evaluate process stability. We use the NASA Space Shuttle flight software to illustrate our approach.
Transverse phase space mapping of relativistic electron beams using optical transition radiation

Optical transition radiation (OTR) has proven to be a versatile and effective diagnostic for measuring the profile, divergence, and emittance of relativistic electron beams with a wide range of parameters. Diagnosis of the divergence of modern high brightness beams is especially well suited to OTR interference (OTRI) techniques, where multiple dielectric or metal foils are used to generate a spatially coherent interference pattern. Theoretical analysis of measured OTR and OTRI patterns allows precise measurement of electron beam emittance characteristics. Here we describe an extension of this technique to allow mapping of divergence characteristics as a function of transverse coordinates within a measured beam. We present the first experimental analysis of the transverse phase space of an electron beam using all optical techniques. Comparing an optically masked portion of the beam to the entire beam, we measure different angular spread and average direction of the particles. Direct measurement of the phase-space ellipse tilt angle has been demonstrated using this optical masking technique.
Determination of plasma topotecan and its metabolite N-desmethyl topotecan as both lactone and total form by reversed-phase liquid chromatography with fluorescence detection

Topotecan (TPT) undergoes hepatic N-demethylation forming N-desmethyl topotecan (NDS). To evaluate the effect of drug-drug interactions on NDS disposition in children receiving TPT we developed and validated a sensitive and specific HPLC-fluorescence detection method for lactone and total (lactone plus carboxylate) TPT and NDS. Deproteinized plasma is vortexed, centrifuged, and the methanolic extract diluted with water for the lactone form of NDS and TPT or diluted with 1.5% phosphoric acid for NDS and TPT total. A 100 microL sample is injected onto a Varian ChromGuard RP column attached to an Agilent SB-C(18) reversed-phase analytical column held at 50 degrees C. The mobile phase (flow-rate, 0.8 mL/min) consists of methanol-aqueous buffer (27:73, v/v) (75 mM potassium phosphate and 0.2% triethylamine, pH 6.5). TPT and NDS were detected with excitation and emission wavelengths set at 376 and 530 nm, respectively. The standard curves for both forms of TPT ranged from 0.25 to 80 ng/mL, and for NDS ranged from 0.10 to 8.0 ng/mL. Within-day and between-day precision (% RSD) was </=4% for TPT and </=6.2% for NDS, respectively. Within-day and between-day percentage error ranged from 1.4 to 6.3% and from 1.4 to 2.4% for TPT, and from 1.6 to 3.1% and from 0.0 to 3.7% for NDS, respectively. No significant on-column conversion from TPT or NDS lactone to carboxylate was observed. With one method we can measure lactone and total TPT and NDS with adequate sensitivity to allow for evaluation of the disposition of these compounds in children receiving TPT.
Thermal decomposition of methyl nitrite in shock waves studied by laser probing

The unimolecular decomposition of methyl nitrite in the temperature range 680–955 K and pressure range 0.64 to 2.0 atm has been studied in shock-tube experiments employing real-time absorption of CW CO laser radiation by the NO product. Computer kinetic modeling using a set of 23 reactions shows that NO product is relatively unreactive. Its initial rate of production can be used to yield directly the unimolecular rate constant, which in the fall-off region, can be represented by the second-order rate coefficient in the Arrhenius form: A RRKM model calculation, assuming a loose CH3ONO≠ complex with two degrees of free internal rotation, gives good agreement with the experimental rate constants.
From First Impression to Fairness Perception: Investigating the Impact of Initial Trustworthiness Beliefs

Evolutionary theory and neuroscientific evidence suggest that humans automatically infer the trustworthiness of others based on facial appearance. Building upon this knowledge base, this article presents three empirical studies that investigate the influence of initial impressions of trustworthiness on post-event perceptions of justice. Across 2 vignette studies and 1 laboratory study, the results consistently suggest that pre-event trustworthiness impressions exert significant indirect effects on post-event justice perceptions. In Study 1 and 2, the effects of trustworthiness were mediated by individuals’ psychological state of trust and fairness-related counterfactual thinking, respectively. In Study 3, the indirect effect of trustworthiness was transmitted through the psychological state of trust alone. The finding that initial trustworthiness impressions derived from surface cues (facial appearance) help shape subsequent perceptions of justice has important implications for justice theory and research.
Nickellike Gadolinium Spectra from the Plt Tokamak

Spectra in the 7 to 9 A region of gadolinium were measured on the PLT tokamak with a vacuum curved crystal spectrometer. The wavelength are compared with theoretical predictions from the RAC code for iron, cobalt, nickel, copper, and zinclike chargestates.
Locally Optimally Emitting Clouds and the Narrow Emission Lines in Seyfert Galaxies

The narrow emission line spectra of active galactic nuclei are not accurately described by simple photoionization models of single clouds. Recent Hubble Space Telescope images of Seyfert 2 galaxies show that these objects are rich with ionization cones, knots, filaments, and strands of ionized gas. Here we extend to the narrow-line region the locally optimally emitting cloud (LOC) model, in which the observed spectra are predominantly determined by powerful selection effects. We present a large grid of photoionization models covering a wide range of physical conditions and show the optimal conditions for producing many of the strongest emission lines. We show that the integrated narrow-line spectrum can be predicted by an integration of an ensemble of clouds, and we present these results in the form of diagnostic line ratio diagrams making comparisons with observations. We also predict key diagnostic line ratios as a function of distance from the ionizing source and compare these with observations. The predicted radial dependence of the [O III]/[O II] ratio may be matched to the observed one in NGC 4151, if the narrow-line clouds see a more intense continuum than we see. The LOC scenario when coupled with a simple Keplerian gravitational velocity field will quite naturally predict the observed line width versus critical density relationship. The influence of dust within the ionized portion of the clouds is discussed, and we show that the more neutral gas is likely to be dusty, although a high-ionization dust-free region is most likely present too. This argues for a variety of narrow-line region cloud origins.
Different Bounds on the Different Betti Numbers of Semi-Algebraic Sets

Abstract. A classic result in real algebraic geometry due to Oleinik—Petrovskii, Thom and Milnor, bounds the topological complexity (the sum of the Betti numbers) of basic semi-algebraic sets. This bound is tight as one can construct examples having that many connected components. However, till now no significantly better bounds were known on the individual higher Betti numbers. We prove better bounds on the individual Betti numbers of basic semi-algebraic sets, as well as arrangements of algebraic hypersurfaces. As a corollary we obtain a polynomial bound on the highest Betti numbers of basic semi-algebraic sets defined by quadratic inequalities.
Euclidean scissor congruence groups and mixed Tate motives over dual numbers

We define Euclidean scissor congruence groups for an arbitrary algebraically closed field F and propose their conjectural description. We suggest how they should be related to mixed Tate motives over dual numbers for F.
A Life Cycle Perspective on Changes in Earnings Inequality among Married Men and Women

Abstract The connection between changes in earnings inequality of individuals and changes in family earnings involves several links: the movements in the employment of different family members, the association between changes in husbands' and in wives' earnings, and patterns of assortative mating. A decomposition of the logarithm of the coefficient of variation in family earnings identifies these links. The data on the dispersion of family earnings are organized not simply over time, but also by age. The growth in wives' relative employment and earnings has partly offset the effects on family earnings inequality of the increase in husbands' earnings inequality.
Mars and Venus Orbiter Spacecraft Electric Propulsion Systems

Mars and Venus orbiter spacecraft electric propulsion system, discussing Hg electron bombardment ion engine
Resummed quantum gravity

We present the current status of the new approach to quantum general relativity based on the exact resummation of its perturbative series as this series was formulated by Feynman. We show that the resummed theory is UV-finite and we present some phenomenological applications as well.
HOW MUCH INFORMATION CAN THERE BE IN A REAL NUMBER

This note gives some information about the magical number Ω and why it is of interest. Our purpose is to explain the significance of recent work by Calude and Dinneen attempting to compute Ω. Furthermore, we propose measuring human intellectual progress (not scientific progress) via the number of bits of Ω that can be determined at any given moment in time using the current mathematical theories.
An analog of Karmarkar's algorithm for inequality constrained linear programs, with a 'new' class of projective transformations for centering a polytope

We present an algorithm, analogous to Karmarkar's algorithm, for the linear programming problem: maximize c^Tx subject to Ax =< b, which works directly to the space of linear inequalities. The main new idea in this algorithm is the simple construction of a projective transformation of the feasible region that maps the current iterate x to the analytic center of the transformed feasible region.
Frequency of Usage: The Impact of Technology Acceptance Factors versus Social Factors

The social networking population continues to expand at a phenomenal pace. Nevertheless, the question of how an organization gets people to spend long periods on a particular social networking website as well as return to the website is becoming increasingly important. Is the technological sophistication of the website or the social aspect most important? This study addresses technological and social factors. The authors examine social network use by employing a survey instrument to gather data about technological factors based on the technology acceptance model and social factors collecting data on constructs representing social involvement and the sheer enjoyment of using the social networking website. Results of the study suggest that users of social networks are more apt to frequently use a site based upon social/enjoyment factors as opposed to technology-related factors.
Synthesis of ethyl N-(diphenyl)methyl-1,2,3,4-tetrahydroisoquinoline-3-carboxylates

Abstract A concise method for the synthesis of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid derivatives from α , α ′-dibromo- o -xylenes via sequential C-alkylation and N-alkylation of a glycine anion is described.
Arithmetic functions at consecutive shifted primes

For each of the functions f ∈ {φ, σ, ω, τ} and every natural number K, we show that there are infinitely many solutions to the inequalities f(pn - 1) f(pn+1 - 1) > ⋯ > f(pn+K -1). We also answer some questions of Sierpinski on the digit sums of consecutive primes. The arguments make essential use of Maynard and Tao's method for producing many primes in intervals of bounded length.
ProbCD: enrichment analysis accounting for categorization uncertainty

As in many other areas of science, systems biology makes extensive use of statistical association and significance estimates in contingency tables, a type of categorical data analysis known in this field as enrichment (also over-representation or enhancement) analysis. In spite of efforts to create probabilistic annotations, especially in the Gene Ontology context, or to deal with uncertainty in high throughput-based datasets, current enrichment methods largely ignore this probabilistic information since they are mainly based on variants of the Fisher Exact Test. We developed an open-source R-based software to deal with probabilistic categorical data analysis, ProbCD, that does not require a static contingency table. The contingency table for the enrichment problem is built using the expectation of a Bernoulli Scheme stochastic process given the categorization probabilities. An on-line interface was created to allow usage by non-programmers and is available at: http://xerad.systemsbiology.net/ProbCD/ . We present an analysis framework and software tools to address the issue of uncertainty in categorical data analysis. In particular, concerning the enrichment analysis, ProbCD can accommodate: (i) the stochastic nature of the high-throughput experimental techniques and (ii) probabilistic gene annotation.
Participatory sensing: applications and architecture

Participatory sensing is the process whereby individuals and communities use ever-more-capable mobile phones and cloud services to collect and analyze systematic data for use in discovery. The convergence of technology and analytical innovation with a citizenry that is increasingly comfortable using mobile phones and online social networking sets the stage for this technology to dramatically impact many aspects of our daily lives.Participatory sensing can serve as a powerful "make a case" technology to support advocacy and civic engagement. It can provide a framework in which citizens can bring to light a civic bottleneck, hazard, personal-safety concern, cultural asset, or other data relevant to urban and natural-resources planning and services, all using data that are systematic and can be validated (http://whatsinvasive.com.) The same systems can be used as tools for sustainability. For example, individuals and communities can explore their transportation and consumption habits and corporations can promote more sustainable practices among employees (http://peir.cens.ucla.edu and http://biketastic.com.)
Polar coding for fading channels

A polar coding scheme for fading channels is proposed in this paper. More specifically, the focus is on the Gaussian fading channel with a BPSK modulation, where the equivalent channel is modeled as a binary symmetric channel with varying cross-over probabilities. To deal with variable channel states, a coding scheme of hierarchically utilizing polar codes is proposed. In particular, by observing the polarization of different binary symmetric channels over different fading blocks, each channel use corresponding to a different polarization is modeled as a binary erasure channel such that polar codes could be adopted to encode over blocks. It is shown that the proposed coding scheme, without instantaneous channel state information at the transmitter, achieves the capacity of the corresponding fading binary symmetric channel.
Tax‐Motivated Expense Allocations by Nonprofit Organizations

Although nonprofit organizations are generally exempt from income taxation, they pay taxes on profits from activities unrelated to their primary exempt purpose. Congress intended this tax on unrela...
The oxidation-reduction potential of copper-bleomycin

Abstract The oxidation-reduction potential of Cu(II)-bleomycin was measured at 25 °C, pH 7.0. With dithionite as reductant, the potential was −105 ± 9 mV with an n value near unity. With cysteine as reductant, the potential was −49 ± 10 mV, with an n value substantially greater than unity. The potentials are within a range that would allow the reduction of Cu(II)-bleomycin to take place in a cell.
Forecasting Marketing-Mix Responsiveness for New Products

Abstract Before a new product launch, marketers need to infer how demand will respond to various levels of marketing-mix variables to set an appropriate marketing plan. A critical challenge in estimating marketing-mix responsiveness from historical data is that the observed decisions were affected by private information possessed by managers about the heterogeneous effects of marketing-mix variables on sales. The authors refer to this as the “slope endogeneity” problem. Such endogeneity differs from the “intercept endogeneity” problem, which has been widely acknowledged in the literature. To correct for the slope endogeneity bias, the authors develop a conceptually simple control function approach that is amenable to multiple endogenous variables and marketing-mix carryover effects. The method is applied to forecasting advertising responsiveness in the U.S. DVD market. The results suggest that advertising responsiveness varies substantially across DVD titles and that estimated marketing-mix elasticities w...
Complement activation produced by biomaterials.

: : The complement-activating potential of biomaterials may be defined by appropriate application of C3a and C5a anaphylatoxin radioimmunoassays. Studies performed with hemodialysis membranes demonstrate that blood contact with these model biomaterials results in complement activation that may be ascribed to specific properties of the material surface. Further delineation of these chemical and physical properties may permit design of biocompatible materials.
Search for low-mass dark matter at BABAR

This review briefly describes light dark matter searches performed by the BABAR experiment. Although dark matter candidates have traditionally been associated with heavy particles appearing in extensions of the Standard Model, a lighter component remains a well-motivated alternative, and many scenarios of light dark matter have been recently proposed. Thanks to their large luminosities, B factories offer an ideal environment to probe these possibilities, complementing searches from direct detection and satellite experiments.
Photochemical reactions of sulfide-containing alkyl phenylglyoxylates

Abstract Ethylthioalkyl phenylglyoxylates (2) underwent regioselective photocyclization to produce up to 13-membered ring thiacyclols (3) in good yields. Cyclization occurred between the excited carbonyl group and the carbon a to the sulfur on the remote side. The more methylenes placed between the carbonyl group and the sulfide, the lower the yield of 3 while intermolecular hydrogen abstraction induced reductive dimerization and intramolecular Norrish Type II photolysis become competitive. The remote cyclization can be rationalized by a photoinduced electron transfer from the sulfur atom to the excited carbonyl group followed by proton transfer and subsequent cyclization of the resulting biradical. Rate constants for electron transfer increase as the chain connecting the electron donor and acceptor becomes longer and more flexible.
Successful Delivery of Public-Private Partnerships for Infrastructure Development

Two common approaches have been used by governments for the implementation of public-private partnerships (PPPs): a finance-based approach that aims to use private financing to satisfy infrastructure needs, and a service-based approach that aims to optimize the time and cost efficiencies in service delivery. The implementation of PPPs, however, may suffer from legal, political, and cultural impediments. In the United States, the federal government enabled a number of acts to ease the impediments and promote PPPs for infrastructure development. Based on a detailed analysis of PPPs in the United Kingdom and British Columbia, Canada, this paper describes principles that would characterize the implementation of PPPs at the program level (e.g., whether the implementation is successful). The principles pertain to the: availability of a PPP legal framework and implementation units; perception of the private finance objectives, risk allocation consequences, and value-for-money objectives; maintenance of PPPs process transparency; standardization of procedures; and use of performance specifications. Guidelines for successful implementation are explained and discussed in the context of the United States PPPs experience and impediments.
Testing Fair Wage Theory

Fairness considerations often are invoked to explain wage differences that appear unrelated to worker characteristics or job conditions, but non-experimental tests of fair wage models are rare because market data rarely permit researchers to measure individual workers’ productivity and its value. We use data from the baseball labor market to address this problem, and find no support for fair wage theory. We do find, however, that fairness premia can be illusory: Wages appear to incorporate fairness premia in regressions that control for variation in individuals’ physical output, but such premia evaporate when the value of that output is held constant.
Design, prototyping, and evaluation of a collapsible device for single-operator sheathing of ultrasound probes

Abstract. During interventional ultrasound-guided procedures, sterility is maintained by covering the transducer head and cord with a sterile sheath. The current sheathing technique is cumbersome, requires an assistant to complete, and poses a risk of tangling the probe cord and breaching the sterile barrier. This paper presents the design, proof-of-concept prototyping, and evaluation of a probe holder and cartridge-style, single-use applicator that enables faster, more reliable, single-user sheathing of ultrasound probes, with a decreased risk of compromising sterility.
Incorporation of helium, neon, argon, krypton, and xenon into fullerenes using high pressure

To investigate the spectroscopic and other properties of these interesting noble gas compounds, it is necessary to increase the fraction of fullerene molecules occupied. We have done this by carrying out the incorporation step at high pressures of the gas. Part-per-million levels of the noble gases produce no measurable effects in the conventional mass spectrum, since the peaks due to ions containing these atoms are well below the noise level. However, samples of fullerene heated in the presence of Ne (38,000 psi, 66% recovery), Ar (40,000 psi, 45% recovery), Kr (24,500 psi, 25% recovery), and Xe (18,000 psi, 45% recovery) show distinct and reproducible peaks (electron impact ionization) for fullerene ions containing the noble gases. The theoretical mass spectra of the corresponding adducts were calculated using the natural isotopic abundance of the involved atoms. Agreement between calculated and experimental curves provides convincing evidence that Ne C[sub 60], Ar C[sub 60], Kr C[sub 60], Xe C[sub 60], Ne C[sub 70], Ar C[sub 70], Kr C[sub 70], and Xe C[sub 70] have been synthesized. 18 refs., 2 figs.
The Stellar Initial Mass Function at the Epoch of Reionization

I provide estimates of the ultraviolet and visible light luminosity density at z ~ 6 after accounting for the contribution from faint galaxies below the detection limit of deep HST and Spitzer surveys. I find that the rest-frame V-band luminosity density is a factor of ~2-3 below the ultraviolet luminosity density at z ~ 6. This implies that the maximal age of the stellar population at z ~ 6, for a Salpeter initial mass function (IMF) and a single, passively evolving burst, must be less than or similar to 100 Myr. If the stars in z ~ 6 galaxies are remnants of the star formation that was responsible for ionizing the intergalactic medium, reionization must have been a brief process that was completed at z 7 is (1.3 ± 0.4) × 10^7 M☉ Mpc^(−3).
Poisson brackets on rational functions and multi-Hamiltonian structure for integrable lattices

We introduce a family of compatible Poisson brackets on the space of rational functions with denominator of a fixed degree and use it to derive a multi-Hamiltonian structure for a family of integrable lattice equations that includes both the standard and the relativistic Toda lattices.
A cavity effect on optical forces

Using an analytically solvable model of a nanoparticle interacting with a spherical optical resonator we show that particle-induced modification of the cavity mode renders standard gradient approximation for the optomechanical interaction invalid. Due to confinement, the optical force acquires a nonconservative component not related to photon scattering.
Doing Publishable Research with Undergraduate Students

Many economics majors write a senior thesis. Although this experience can be the pinnacle of their education, publication is not the common standard for undergraduates. The authors describe four approaches that have allowed students to get their work published: (1) identify a topic, such as competitive balance in sports, and have students work on various subtopics, such as specific sports; (2) develop a large data set and have students work on different problems using it; (3) divide a quantitative problem into distinct parts and have individual students work on each part; and (4) divide a qualitative problem into distinct parts and have individual students work on their own part. The authors also address the challenges of working with undergraduates: limited time and resources, limited skills, and the tedium of gathering data.
Ergodicity of mapping class group actions on representation varieties, I. Closed surfaces

We prove that the mapping class group of a closed surface acts ergodically on connected components of the representation variety corresponding to a connected compact Lie group.
Status of the James Webb Space Telescope integrated science instrument module system

The Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST) is discussed from a systems perspective with emphasis on development status and advanced technology aspects. The ISIM is one of three elements that comprise the JWST space vehicle and is the science instrument payload of the JWST. The major subsystems of this flight element and their build status are described.
On the Speed of Spread for Fractional Reaction-Diffusion Equations

The fractional reaction diffusion equation ∂tu+Au=g(u) is discussed, where A is a fractional differential operator on ℝ of order α∈(0,2), the C1 function g vanishes at ζ=0 and ζ=1, and either g≥0 on (0,1) or g 1, or if g is merely positive on a sufficiently large interval near ζ=1 in the case α<1. On the other hand, it shown that solutions spread with finite speed if g′(0)<0. The proofs use comparison arguments and a suitable family of travelling wave solutions.
Electrochemical switching in anthraquinone-substituted carbon-pivot lariat ethers and podands: chain length effects in geometric and electronic cooperativity.

Synthese d'une serie d'anthraquinones substituees en −1 (ou Ar) par le substituant E=−CH 2 CH 2 - avec formation d'Ar-OCH 3 , Ar-OEOEOCH 3 , Ar-OEOEOEOCH 3 , Ar-OEOEOEOEOCH 3 , Ar-OEOEOEOEOEOCH 3 , Ar-OEOEOEO-Ar et d'Ar-O-CH 2 -15-crown-5. Mise en evidence de l'existence de couples redox a un ou 2 electrons (voltammetrie cyclique) dans le cas des differents systemes lors de l'addition d'ions Li + , Na + et K + . Le comportement electrochimique est complexe et est en accord avec une combinaison de facteurs electroniques et steriques