cssi/SciSciGPT-SciSciNet huggingface dataset:
Fens as whole-ecosystem gauges of groundwater recharge under climate change

Summary Currently, little is known about the impact of climate change on groundwater recharge in the Sierra Nevada and southern Cascade Range of California or other mountainous regions of the world. The purpose of this study was to determine whether small alpine peatlands called fens can be used as whole-ecosystem gauges of groundwater recharge through time. Fens are sustained by groundwater discharge and are highly sensitive to changes in groundwater flow due to hydrologic disturbance including climate change. Seven fens in the Sierra Nevada and southern Cascade Range were studied over a 50–80 year period using historic aerial photography. In each aerial photograph, fen areas were identified as open lawn and partially treed areas that exhibited (1) dark brownish-green coloring or various shades of gray and black in black and white imagery and (2) mottling of colors and clustering of vegetation, which signified a distinct moss canopy with overlying clumped sedge vegetation. In addition to the aerial photography study, a climate analysis for the study sites was carried out using both measured data (U.S. Department of Agriculture Natural Resources Conservation Service SNOwpack TELemetry system) and modeled data (a downscaled version of the Parameter-elevation Regressions on Independent Slopes Model) for the period from 1951 to 2010. Over the study period, the five fens in the Sierra Nevada were found to be decreasing between 10% and 16% in delineated area. The climate analysis revealed significant increases through time in annual mean minimum temperature (Tmin) between 1951–1980 and 1981–2010. In addition, April 1 snow water equivalent and snowpack longevity also decreased between 1951–1980 and 1981–2010. For the fens in the Cascade Range, there were no discernible changes in delineated area. At these sites, increases in Tmin occurred only within the past 20–25 years and decreases in snowpack longevity were more subtle. A conceptual model is presented, which illustrates that basic differences in hydrogeology of the Sierra Nevada vs. the Cascade Range may control the threshold at which changes in delineated fen areas are discernible. Overall, the results from this study show that fens in the Sierra Nevada have strong potential as whole-ecosystem gauges for determining long-term changes in groundwater recharge under climate change. Due to either more moderate climate change and/or hydrogeological differences, fens in the southern Cascade Range currently do not appear to have the same utility. A greater sample size of fens in the Sierra Nevada is needed to confirm the general applicability of this method. In addition, future work needs to focus on integrating fen monitoring with geochemical and/or isotopic process-level studies in order to quantify changes in groundwater recharge identified using this new approach.
Diploptene: An Indicator of terrigenous organic carbon in Washington coastal sediments

The pentacyclic triterpene 17 beta(H),21 beta(H)-hop-22(29)-ene (diploptene) occurs in sediments throughout the Columbia River drainage basin and off the southern coast of Washington state in concentrations comparable to long-chain plantwax n-alkanes. The same relationship is evident for diploptene and long-chain n-alkanes in soils from the Willamette Valley. Microorganisms indigenous to soils and soil erosion are indicated as the biological source and physical process, respectively, for diploptene in coastal sediments. Similarity between the stable carbon isotopic composition (delta 13CPDB) of diploptene isolated from soil in the Willamette Valley (-31.2 +/- 0.3%) and from sediments deposited throughout the Washington coastal environment (-31.2 +/- 0.5%) supports this argument. Values of delta for diploptene in river sediments are variable and 8-17% lighter, indicating that an additional biological source such as methane-oxidizing bacteria makes a significant contribution to the diploptene record in river sediments. Selective biodegradation resulting from a difference in the physicochemical association within eroded particles can explain the absence of the more-13C-depleted form of diploptene in Washington coastal sediments, but this mechanism remains unproven.
A perovskite oxide optimized for oxygen evolution catalysis from molecular orbital principles.

The efficiency of many energy storage technologies, such as rechargeable metal-air batteries and hydrogen production from water splitting, is limited by the slow kinetics of the oxygen evolution reaction (OER). We found that Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3–δ (BSCF) catalyzes the OER with intrinsic activity that is at least an order of magnitude higher than that of the state-of-the-art iridium oxide catalyst in alkaline media. The high activity of BSCF was predicted from a design principle established by systematic examination of more than 10 transition metal oxides, which showed that the intrinsic OER activity exhibits a volcano-shaped dependence on the occupancy of the 3d electron with an e g symmetry of surface transition metal cations in an oxide. The peak OER activity was predicted to be at an e g occupancy close to unity, with high covalency of transition metal–oxygen bonds.
The imaginary part of the gravity action and black hole entropy

As observed recently in arXiv:1212.2922 , the action of General Relativity (GR) in finite spacetime regions has an imaginary part that resembles the Bekenstein entropy. In this paper, we expand on that argument, with attention to different causal types of boundaries. This property of the GR action may open a new approach to the puzzles of gravitational entropy. In particular, the imaginary action can be evaluated for non-stationary finite regions, where the notion of entropy is not fully understood. As a first step in constructing the precise relationship between the imaginary action and entropy, we focus on stationary black hole spacetimes. There, we identify a class of bounded regions for which the action’s imaginary part precisely equals the black hole entropy. As a powerful test on the validity of the approach, we also calculate the imaginary action for Lovelock gravity. The result is related to the corresponding entropy formula in the same way as in GR.
Origin of Gamma Ray Bursters

The successful discovery of X-ray, optical and radio afterglows of GRB has made possible the identification of host galaxies at cosmological distances. The energy release inferred in these outbursts place them among the most energetic and violent events in the Universe. They are thought to be the outcome of a cataclysmic stellar collapse or compact stellar merger, leading to a relativistically expanding fireball, in which particles are accelerated at shocks and produce nonthermal radiation. The substantial agreement between observations and the theoretical predictions of the fireball shock model provide confirmation of the basic aspects of this scenario. Among recent issues are the collimation of the outflow and its implications for the energetics, the production of prompt bright flashes at wavelenghts much longer than gamma-rays, the time structure of the afterglow, its dependence on the central engine or progenitor system behavior, and the role of the environment on the afterglow.
Interception in three dimensions - An energy formulation

The problem of minimum-time interception of a target flying in three dimensional space is analyzed with the interceptor aircraft modeled through energy-state approximation. A coordinate transformation that uncouples the interceptor's extremals from the target motion in an open-loop sense is introduced, and the necessary conditions for optimality and the optimal controls are derived. Example extremals are shown.
Molecular structures of 4,13-diaza-18-crown-6 derivatives having glycyl-glycine sidearms: two potassium iodide complexes

Abstract Solid state structures are presented for two crystalline K+ complexes of N,N′-bis(methyl glycidylglycidino)-4,13-diaza-18-crown-6. The two different complexes co-crystallize and both structures are fully resolved. The sidearm-K+ interactions differ in each but in both cases the proximal (amide) carbonyl participates in cation binding while the distal (ester) carbonyl does not.
Assessing the impact of animal waste lagoon seepage on the geochemistry of an underlying shallow aquifer.

Evidence of seepage from animal waste holding lagoons at a dairy facility in the San Joaquin Valley of California is assessed in the context of a process geochemical model that addresses reactions associated with the formation of the lagoon water as well as reactions occurring upon the mixture of lagoon water with underlying aquifer material. Comparison of model results with observed concentrations of NH 4 + , K + , PO 4 3- , dissolved inorganic carbon, pH, Ca 2+ , Mg 2+ , SO 4 2- , Cl - , and dissolved Ar in lagoon water samples and groundwater samples suggests three key geochemical processes: (i) off-gassing of significant quantities of CO 2 and CH 4 during mineralization of manure in the lagoon water, (ii) ion exchange reactions that remove K + and NH 4 + from seepage water as it migrates into the underlying anaerobic aquifer material, and (iii) mineral precipitation reactions involving phosphate and carbonate minerals in the lagoon water in response to an increase in pH as well as in the underlying aquifer from elevated Ca 2+ and Mg 2+ levels generated by ion exchange. Substantial off-gassing from the lagoons is further indicated by dissolved argon concentrations in lagoon water samples that are below atmospheric equilibrium. As such, Ar may serve as a unique tracer for lagoon water seepage since under-saturated Ar concentrations in groundwater are unlikely to be influenced by any processes other than mechanical mixing.
Can a Wrongful Discharge Statute Really Benefit Employers

Overall, there is overwhelming empirical support for the hypothesis that the Wrongful Discharge From Employment Act benefited employers in Montana. Shareholder returns were significantly higher given the Act than they would have been absent the law. This reflects shareholders' estimate of the effects of the Act on the future profitability of their firms. The increase in profitability would have been due to the benefits the Act gave to employers in Montana.
What do computers eat? Teaching beginners to think critically about technology and art

Abstract This paper presents new curriculum for an introductory course in art and technology. Here students compare the software industry with fast food to investigate and critique patterns of consumption in our culture. Relevant readings, assignments, and tutorials can be found online at http://www.tiffanyholmes.com/fundamentals .
Viscoelastic and photoelastic properties of polystyrene above its softening temperature

Abstract Creep, recovery, and stress-relaxation experiments with simultaneous measurements of birefringence have been carried out on polystyrene films above their softening temperature. The ratio of birefringence to stress is a constant independent of the stress, elongation, temperature, and molecular weight of the polystyrene. The data indicate that polystyrene has a semipermanent network structure. The network is most likely caused by the strong intertwining of the polymer molecules.
Markov type and threshold embeddings

For two metric spaces X and Y, say that X threshold-embeds into Y if there exist a number K > 0 and a family of Lipschitz maps \({\{\varphi_{\tau} : X \to Y : \tau > 0\}}\) such that for every \({x,y \in X}\), $$d_X(x, y) \geq \tau \implies d_Y(\varphi_\tau (x),\varphi_\tau (y)) \geq \|{\varphi}_\tau\|_{\rm Lip}\tau/K,$$ where \({\|{\varphi}_{\tau}\|_{\rm Lip}}\) denotes the Lipschitz constant of \({\varphi_{\tau}}\). We show that if a metric space X threshold-embeds into a Hilbert space, then X has Markov type 2. As a consequence, planar graph metrics and doubling metrics have Markov type 2, answering questions of Naor, Peres, Schramm, and Sheffield. More generally, if a metric space X threshold-embeds into a p-uniformly smooth Banach space, then X has Markov type p. Our results suggest some non-linear analogs of Kwapien’s theorem. For instance, a subset \({X \subseteq L_1}\) threshold-embeds into Hilbert space if and only if X has Markov type 2.
The concordance cosmic star formation rate: implications from and for the supernova neutrino and gamma ray backgrounds

We constrain the cosmic star formation rate (CSFR) by requiring that massive stars produce the observed UV, optical, and IR light and at the same time not overproduce the diffuse supernova neutrino background as bounded by Super-Kamiokande. With the massive star component so constrained we then show that a reasonable choice of stellar initial mass function and other parameters results in SNIa rates and iron yields in good agreement with data. In this way we define a 'concordance' CSFR that predicts the optical SNII rate and the SNIa contribution to the MeV cosmic gamma ray background. The CSFR constrained to reproduce these and other proxies of intermediate and massive star formation is more clearly delineated than if it were measured by any one technique and has the following testable consequences: (1) SNIa contribute only a small fraction of the MeV cosmic gamma ray background, (2) massive star core collapse is nearly always accompanied by a successful optical SNII, and (3) the diffuse supernova neutrino background is tantalizingly close to detectability.
An Improved Synthesis of (+)-3,4-O-Isopropylidene Butyne

Abstract (+)-3, 4-O-Isopropylidene butyne ( 1 ) has been prepared in 81% isolated yield from (+)-2, 3-isopropyli-dene-D-glyceraldehyde ( 2 ) using a modified Corey-Fuchs procedure.
First principles molecular dynamics of dense plasmas.

Ab initio molecular dynamics calculations are performed for the equation of state of aluminum, spanning condensed matter and dense plasma regimes. Electronic exchange and correlation are included with either a zero- or finite-temperature local density approximation potential. Standard methods are extended to above the Fermi temperature by using final state pseudopotentials to describe thermally excited ion cores. The predicted Hugoniot equation of state agrees well with earlier plasma theories and with experiment for temperatures from 0 to $3\ifmmode\times\else\texttimes\fi{}{10}^{6}\mathrm{K}$.
Exact Lattice Supersymmetry at Large N

Employing a novel type of non-commutative product in the Dirac-Kahler twisted superspace on a lattice, we formulate a field theoretically rigid framework of extended supersymmetry on a lattice. This corresponds to a certain reformulation of the non-commutative superspace on a lattice which was essentially developed in ref. [1]. As a first example of this treatment, we calculate one-loop (in some cases any loops) quantum corrections for a twisted Wess-Zumino model with N × N hermitian matrix superfields on a two dimensional lattice. The calculations are entirely given in a lattice superfield framework. We report that the mass and the coupling constant are exactly protected from the radiative corrections at non-zero lattice spacing as far as the planar diagrams are concerned, while the non-planar contributions generally spoil the exactness of the supersymmetry at finite N on the lattice. These properties imply an exact lattice supersymmetry realization w.r.t. all the supercharges in the 't Hooft large-N limit.
Ferromagnetic resonance in a Ni-Mo superlattice

Ferromagnetic resonance (FMR) measurements, at room temperature and at 4.2 K, have been made on a layered Ni (249 A)‐Mo(83 A) superlattice. We have examined the resonance position as a function of the angle between the film normal and the applied field. The measured g value agrees with that of bulk Ni, but the magnetization is lower than that obtained for bulk Ni and also for this sample using both light scattering and direct measurement techniques. This low magnetization contrasts with FMR measurements on compositionally modulated Ni‐Cu samples, where the magnetization was reported to be greater than that of bulk Ni. We show that a reduced value of the magnetization is consistent with perpendicular uniaxial anisotropy. When the applied field is less than 20° from the surface normal, additional lines appear that move to higher fields than the main resonance. These lines are consistent with the existence of nonuniform regions of distinct magnetization. An observed resonance, which is suggestive of a spin‐w...
Capital Budgets, Borrowing Rules, and State Capital Spending

Abstract This paper compares the level and composition of government spending in U.S. states that maintain separate budgets for capital and operating expenditures with that in states that employ unified budgets. It also investigates the effects of pay-as-you-go financing rules for capital projects. The empirical findings suggest that states with separate capital budgets spend more on public capital projects than comparable states with unified budgets. There is no evidence that the presence or absence of a capital budget affects the level of non-capital spending. Pay-as-you-go requirements for financing capital projects are associated with lower levels of both capital and non-capital spending.
Impact of space shuttle orbiter reentry on mesospheric NOx.

Shuttle orbiter reentry will produce large amounts of nitric oxide (NO) through shock heating at mesospheric altitudes. The effects of this reentry are modeled by considering an impulsive source of NO in time-dependent equations including photochemistry and transport. The model uses an odd-nitrogen approach similar to Strobel's. Parameterized flux boundary conditions are imposed at the mesopause and stratopause and concentrations of the odd nitrogen species (NO, NO2, NO+, N(4S) and N(2D) are found numerically by a finite difference scheme. A localized disturbance can last many hours, depending on the effectiveness of eddy transport. Although the model is one-dimensional, effects of horizontal transport are also included approximately.
CFD-Based Aeroelastic Eigensolver for the Subsonic, Transonic, and Supersonic Regimes

We describe a linearized computational e uid dynamics (CFD) method for computing an arbitrary number of eigensolutions of a given aeroelastic problem. The proposed method is based on the reengineering of a three-way coupled formulation previously developed for the solution in the time domain of nonlinear transient aeroelastic problems. It is applicable in the subsonic, transonic, and supersonic e ow regimes, and independently from the frequency or damping level of the target aeroelastic modes. It is based on the computation of the complex eigensolution of a carefully linearized e uid ‐structure interaction problem, relies on the inverse orthogonal iteration algorithm, and reutilizes existing unsteady e ow solvers. This is a validated method with the e utter analysis of the AGARD Wing 445.6 for which experimental data are available.
A High-eccentricity Component in the Double-planet System around HD 163607 and a Planet around HD 164509

We report the detection of three new exoplanets from Keck Observatory. HD 163607 is a metal-rich G5IV star with two planets. The inner planet has an observed orbital period of 75.29 ± 0.02 days, a semi-amplitude of 51.1 ± 1.4 m s^(–1), an eccentricity of 0.73 ± 0.02, and a derived minimum mass of MP sin i = 0.77 ± 0.02 M_(Jup). This is the largest eccentricity of any known planet in a multi-planet system. The argument of periastron passage is 78.7 ± 2°0; consequently, the planet's closest approach to its parent star is very near the line of sight, leading to a relatively high transit probability of 8%. The outer planet has an orbital period of 3.60 ± 0.02 years, an orbital eccentricity of 0.12 ± 0.06, and a semi-amplitude of 40.4 ± 1.3 m s^(–1). The minimum mass is MP sin i = 2.29 ± 0.16 M _(Jup). HD 164509 is a metal-rich G5V star with a planet in an orbital period of 282.4 ± 3.8 days and an eccentricity of 0.26 ± 0.14. The semi-amplitude of 14.2 ± 2.7 m s^(–1) implies a minimum mass of 0.48 ± 0.09 M_(Jup). The radial velocities (RVs) of HD 164509 also exhibit a residual linear trend of –5.1 ± 0.7 m s–1 year–1, indicating the presence of an additional longer period companion in the system. Photometric observations demonstrate that HD 163607 and HD 164509 are constant in brightness to submillimagnitude levels on their RV periods. This provides strong support for planetary reflex motion as the cause of the RV variations.
Some combinatorial properties of hook lengths, contents, and parts of partitions

The main result of this paper is a generalization of a conjecture of Guoniu Han, originally inspired by an identity of Nekrasov and Okounkov. Our result states that if F is any symmetric function (say over ℚ) and if $$\Phi_n(F)=\frac{1}{n!}\sum_{\lambda\vdash n}f_\lambda^2F(h_u^2:u\in\lambda),$$ where hu denotes the hook length of the square u of the partition λ of n and fλ is the number of standard Young tableaux of shape λ, then Φn(F) is a polynomial function of n. A similar result is obtained when F(hu2:u∈λ) is replaced with a function that is symmetric separately in the contents cu of λ and the shifted parts λi+n−i of λ.
Heavy Flavor Measurements at RHIC in the Near Future

Abstract We discuss the recent results on open charm measurements at RHIC. The heavy flavor upgrade program for both PHENIX and STAR experiments are briefly discussed. The completion of the program will yield important information on light flavor thermalization of the partonic matter created in high-energy nuclear collisions at RHIC. A new era of RHIC is ahead of us with the progress of the upgrade program.
Mechanism-based inactivation of thymidylate synthase by 5-(3-fluoropropyn-1-yl)-2'-deoxyuridine 5'-phosphate.

Abstract 5-Fluoropropynyl-2′-deoxyuridine 5′-phosphate ( 3 ) was designed as a mechanism-based inactivator of thymidylate synthase (TS). The inhibitor was synthesized from 5-iodo-2′-deoxyuridine and propargyl alcohol by palladium-catalyzed coupling, followed by fluorination and selective phosphorylation. Incubation of TS with 3 , in the presence or absence of the CH 2 H 4 folate cofactor, caused rapid, irreversible inactivation of the enzyme.
Magnetic attitude control system for the radio astronomy Explorer-A satellite.

The RAE-A is a 3-axis gravity-stabilized spacecraft in a nominal 6000-km-altitude circular orbit. It includes a magnetic attitude detection and control system designed to orient the spin axis prior to firing the apogee boost motor and, in the final orbit, to provide despin and magnetic stabilization such that gravity capture can be achieved with minimum subsequent librations. This control system weighs 14.5 Ib and requires 5 w maximum power. The hardware consists of a stabilizing electromagnet plus a pair of damping electromagnets driven by magnetic hysteresis function generators. Flux-gate magnetometers drive the hysteresis generators. Despin is alternatively accomplished by generating a nearly constant magnetic torque opposing the spin motion. This paper presents the concept of enhanced magnetic hysteresis damping, design of the RAE control system hardware, use of an analog computer for hardware checkout and prediction of attitude performance, and the flight results in July 1968. The steady-state error in tracking the magnetic field vector was on the order of 20°, with residual spin rates averaging 0.009 rpm.
Inclusive semileptonic b decays at babar

We present measurements of the inclusive semileptonic branching fractions of charged and neutral B mesons using 20.6 fb{sup -1} of data measured at the {Upsilon}(4S) with the BABAR detector. Events are tagged with a fully reconstructed hadronic decay of a B meson. The correlation between the flavor of the tag B meson and the electron charge allows the separation of prompt semileptonic B decays and cascade semileptonic charm decays. We obtain the preliminary inclusive semileptonic branching fraction of charged B mesons b{sub +} = 0.103 {+-} 0.006 {+-} 0.005, neutral B mesons b{sub 0} = 0.104 {+-} 0.008 {+-} 0.005, their average b = 0.104 {+-} 0.005 {+-} 0.004, and their ratio b{sub +}/b{sub 0} = 0.99 {+-} 0.10 {+-} 0.03.
Electron Transfer Photoredox Catalysis: Intramolecular Radical Addition to Indoles and Pyrroles

The utilization of the photoredox catalyst, tris(2,2′-bipyridyl)ruthenium dichloride, and a household light bulb to effect radical cyclizations onto indoles and pyrroles at room temperature is reported. A reactive free radical intermediate is generated via the reduction of an activated C−Br bond by the single electron reductant, Ru(I), generated in a visible light induced photocatalytic cycle. This system represents an expansion of the application of photoredox catalysis in conventional free radical processes.
Entropic nonextensivity: a possible measure of complexity

Abstract An updated review (corresponding to the inaugural talk delivered at the The International Workshop on Classical and Quantum Complexity and Nonextensive Thermodynamics, Denton, TX, April 3–6, 2000) of nonextensive statistical mechanics and thermodynamics is colloquially presented. Quite naturally the possibility emerges for using the value of q −1 (entropic nonextensivity) as a simple and efficient manner to provide, at least for some classes of systems, some characterization of the degree of what is currently referred to as complexity (M. Gell-Mann, The Quark and the Jaguar, Freeman, New York, 1994). A few historical digressions are included as well.
The role of entanglement in dynamical evolution

Entanglement or entanglement-generating interactions permit to achieve the maximum allowed speed in the dynamical evolution of a composite system, when the energy resources are distributed among subsystems. The cases of pre-existing entanglement and of entanglement-building interactions are separately addressed. The role of classical correlations is also discussed.
Female Labor Supply with a Discontinuous, Nonconvex Budget Constraint: Incorporation of a Part-Time/Full-Time Wage Differential

This paper incorporates the well-documented part-time/full-time wage differential into an empirical labor supply model with both a heterogeneity- and a random-error term and estimates that model fo...
Thermal Stability of Magnet Wire Evaluated by Viscoelastic Behavior

This paper outlines a method for testing the thermal stability of magnet wire by measuring the viscoelastic behavior of tubed fims obtained from magnet wire manufactured with standard equipment. It was found that there was a correlation between the glass transition temperature obtained from the mechanical tan ? versus temperature curve and the thermal class obtained from the IEEE No. 57 test method. When a magnet wire is heat aged, the mechanical tan ? peak of the film decreases. Regression curves of the mechanical tan ? peak versus aging temperature and aging time were expressed as second-order curves. The activation energies of heat aging were obtained, and compared to the activation energies obtained from the IEEE No. 57 test method.
The technology factor and the export performance of U. S. manufacturing industries

The paper examines two central theories advanced to explain the revealed comparative advantage of U.S. industries. The neo-technological account centers on the process of innovation among industries and is represented in the regression analysis by an R&D intensity variable. The neofactor theory advances both human and “physical” capital as important variables in determining countries' comparative advantage. Foreign protection is postulated to affect the export performance of U.S. industries. Generally the results suggest that U.S. revealed comparative advantage is most pronounced in R&D intensive industries that give the U.S. a temporary technological lead in world markets.
Time-evolving bubbles in two-dimensional Stokes flow

A general class of exact solutions is presented for a time evolving bubble in a two-dimensional slow viscous flow in the presence of surface tension. These solutions can describe a bubble in a linear shear flow as well as an expanding or contracting bubble in an otherwise quiescent flow. In the case of expanding bubbles, the solutions have a simple behavior in the sense that for essentially arbitrary initial shapes the bubble will asymptote an expanding circle. Contracting bubbles, on the other hand, can develop narrow structures ('near-cusps') on the interface and may undergo 'break up' before all the bubble-fluid is completely removed. The mathematical structure underlying the existence of these exact solutions is also investigated.
Acetal formation by solvolysis of glucal-derived donor–acceptor cyclopropanes

Abstract The conversion of glucal derived donor–acceptor cyclopropanes to acetals by TiCl4 mediated ring opening and alcohol trapping is described. Good selectivity for the alpha anomer and yields near 90% are consistently observed with aliphatic, benzylic and allylic alcohols, phenols and thiophenols. The utility of this method to prepare oligosaccharides through intermediate O,S-acetals is illustrated.
Three‐dimensional compressional wave attenuation tomography for the crust and uppermost mantle of Northern and central California

I present a frequency-independent three-dimensional (3-D) compressional wave attenuation model (indicated by quality factor Qp) for the crust and uppermost mantle of Northern and central California. The tomographic inversion used t∗ values measured from amplitude spectra of 80,988 P wave arrivals of 3247 events recorded by 463 network stations through a 3-D seismic velocity model. The model has a uniform horizontal grid spacing of 15 km, and the vertical node intervals range between 2 and 10 km down to 45 km depth. In general, the resulting Qp values increase with depth and agree with the surface geology at shallow depth layers. The most significant features observed in the Qp model are the high Qp values in the Sierra Nevada mountains and low Qp anomalies in the western fault zones. Low Qp values are also imaged in Owens Valley and Long Valley at shallow depths and the Cape Mendocino region in the lower crust (∼25 km depth). An overall contrast of Qp values across the fault is observed in the creeping, Parkfield and Cholame-Carrizo sections of the San Andreas Fault. The new 3-D Qp model provides an important complement to the existing regional-scale velocity models for interpreting structural heterogeneity and fluid saturation of rocks in the study area.
Judicial Review without a Constitution

In the United States, judicial review is understood, since Marbury v. Madison (1803), as judicial evaluation of government action to ensure compliance with the Constitution. But before and after Marbury, state and federal courts developed and practiced a form of judicial review in which common law principles, along with or instead of a canonical document, were the foundational body of legal doctrine against which public actions were assessed. This article carefully examines the cases in which this alternative form of judicial review emerged, and corrects certain misconceptions that Marbury must be the only form of judicial review that has existed or can exist in this country. More particularly, the article clarifies a failure by certain writers to distinguish properly between common law and natural law as matters of legal theory and legal doctrine. In correcting some of these theoretical and historical errors, the article outlines an understanding of judicial review that more fully captures its developmen...
Mixed states of composite fermions carrying two and four vortices

There now exists preliminary experimental evidence for some fractions, such as $\ensuremath{\nu}=4/11$ and $5/13,$ that do not belong to any of the sequences $\ensuremath{\nu}=n/(2\mathrm{pn}\ifmmode\pm\else\textpm\fi{}1),$ p and n being integers. We propose that these states are mixed states of composite fermions of different flavors, for example, composite fermions carrying two and four vortices. We also obtain an estimate of the lowest-excitation dispersion curve as well as the transport gap; the gaps for $4/11$ are smaller than those for $1/3$ by approximately a factor of 50.
Fabrication of comb-drive micro-actuators based on UV lithography of SU-8 and electroless plating technique

Comb-drive microactuators are widely used in MEMS devices. Most of the comb-drive microactuators reported in MEMS field are made using fabrication technology with silicon as the structural material. Recent progress in ultra violet (UV) lithography of SU-8 has made it feasible to fabricate ultra high aspect ratio microstructures with excellent sidewall quality. In this paper, a research work on fabrication and metallization of high aspect ratio SU-8 polymer comb-drive microactuators was reported. The fabrication process combined multi-step and multi-layer UV lithography of SU-8 on a silicon substrate and copper electroless plating to selectively metallize the SU-8 microstructure. The selective electroless plating was achieved by using UV modification of the SU-8 microstructures and the careful control of the exposure dosage. Preliminary experimental results have proved the feasibility of the microactuator and the fabrication technology.
Asymmetric discounting of gains and losses: A query theory account

People discount delayed gains (where the default is to receive a smaller gain sooner) more than accelerated gains (where the default is to receive a larger gain later). For losses, the pattern reverses—people discount delayed losses less than accelerated losses. In Study 1, confirming a Query Theory process account, this sign by direction interaction is mediated by the prominence of thoughts in favor of the default. Thoughts in favor of the smaller, sooner amount are more prominent in delay scenarios than acceleration scenarios, and this increases discounting for gains and decreases discounting for losses. Study 2 confirms the causal role of the order of option consideration. Participants considering thoughts in the natural order (pro-default thoughts first) replicate the sign by direction interaction, whereas participants considering thoughts in the opposite, unnatural order (pro-alternative thoughts first) do not. Reversing the order of option consideration eliminates the sign by direction interaction.
Low-temperature transport properties of NdBiPt

NdBiPt is a member of a new class of ternary intermetallic semiconductors and semimetals. These materials are covalently bonded crystals with band gaps expected to be in the range of 0{endash}1 eV. Longitudinal resistivity, Hall resistivity, and thermoelectric power measurements reveal that in NdBiPt the {open_quote}{open_quote}gap{close_quote}{close_quote} is an overlap that gives rise to a semimetallic behavior exhibiting high hole and electron mobilities. {copyright} {ital 1996 The American Physical Society.}
Breakdown of the Schmid Law in BCC Molybdenum Related to the Effect of Shear Stress Perpendicular to the Slip Direction

The breakdown of the Schmid law in bcc metals has been known for a long time. The asymmetry of shearing in the slip direction 〈111〉 in the positive and negative sense, respectively, commonly identified with the twinning-antitwinning asymmetry, is undoubtedly one of the reasons. However, effect of stress components other than the shear stress in the slip direction may be important. In this paper we investigate by atomistic modeling the effect of shear stresses perpendicular to the Burgers vector on the glide of a/2〈111〉 screw dislocations. We show that these shear stresses can significantly elevate or reduce the critical resolved shear stress (CRSS) in the direction of the Burgers vector needed for the dislocation motion, i.e. the Peierls stress. This occurs owing to the changes of the core induced by these stresses. This effect may be the reason why slip systems with smaller Schmid factors may be preferred over that with the largest Schmid factor.
An Evaluation of Differential Omega for General Aviation Area Navigation

this paper reports on a study which compared the expected cost and performance of Differential Omega with that of Loran-C and VORTAC for general aviation area navigation. Analysis is directed toward a comparison of the systems with respect to specified performance parameters and the cost-effectiveness of each system in relation to the specifications. Loran-C offers the highest performance with respect to accuracy. Differential Omega requires the least expenditure. It was found cost ineffective to attempt to obtain complete coverage by expanding the existing VORTAC system.
Fishing, Commitment, and Communication: A Proposal for Comprehensive Nonbinding Research Registration

Social scientists generally enjoy substantial latitude in selecting measures and models for hypothesis testing. Coupled with publication and related biases, this latitude raises the concern that researchers may intentionally or unintentionally select models that yield positive findings, leading to an unreliable body of published research. To combat this “fishing” problem in medical studies, leading journals now require preregistration of designs that emphasize the prior identification of dependent and independent variables. However, we demonstrate here that even with this level of advanced specification, the scope for fishing is considerable when there is latitude over selection of covariates, subgroups, and other elements of an analysis plan. These concerns could be addressed through the use of a form of comprehensive registration. We experiment with such an approach in the context of an ongoing field experiment for which we drafted a complete “mock report” of findings using fake data on treatment assignment. We describe the advantages and disadvantages of this form of registration and propose that a comprehensive but nonbinding approach be adopted as a first step to combat fishing by social scientists. Likely effects of comprehensive but nonbinding registration are discussed, the principal advantage being communication rather than commitment, in particular that it generates a clear distinction between exploratory analyses and genuine tests.
Transient Three -Dimensional Side Load Analysis of a Film Cooled Nozzle

Transient t hree -dimensional numerical investigations on the side load physics for a n engine en comp assing a film cooled nozzle extension and a regeneratively cooled thrust chamber , were performed. The objectives of this study are t o identify the side load physics and to compute the associated aerodynamic side load using an anchored computational meth odology. The computational methodology is based on an unstructured -grid, pressure based computational fluid dynamics and heat transfer formulation, and a transient inlet history based on an engine system simulation. Computations simulating engine startup a t ambient pressures corresponding to sea level and three high altitudes were performed . In addition, computations for both engine startup and shutdown transients for a stub nozzle operating at sea level were also performed. For engine startup s with the no zzle extension attached , computational result s show the dominant side load physics are the turbine exhaust gas film coolant induced asymmetric Mach disk flow and the subsequent jump of the shock foot or the jump of the separation line which generated the p eak side load. That peak side load decreases rapidly and progressively as the ambient pressure decreases with the increasing altitudes . For the stub nozzle operating at sea level, t he peak side load reduces drastically and comes from the simultaneous free -shock separation to partial restricted shock transition and the shock breathing a t the nozzle lip during startup, whereas the magnitude of the side load during shut down is almost negligible . The computed side load characteristics for the sea level cases agree re asonably well with those of available data from the tests of a similar engine.
Multi-agent consensus algorithm with obstacle avoidance via optimal control approach

Multi-agent consensus problem in an obstacle-laden environment is addressed in this paper. A novel optimal control approach is proposed for the multi-agent system to reach consensus as well as avoid obstacles with a reasonable control effort. An innovative nonquadratic penalty function is constructed to achieve obstacle avoidance capability from an inverse optimal control perspective. The asymptotic stability and optimality of the consensus algorithm are proven. In addition, the optimal control law of each agent only requires local information from the neighbors to guarantee the proposed behaviors, rather than all agents' information. The consensus and obstacle avoidance are validated through various simulations.
Network Models for Building Evacuation

How can a large building with many occupants be evacuated in minimum time, and where are bottlenecks likely to occur in such an evacuation? In order to address this question we have constructed a f...
A vertex formalism for local ruled surfaces

We develop a vertex formalism for topological string amplitudes on ruled surfaces with an arbitrary number of reducible fibers embedded in a Calabi-Yau threefold. Our construction is based on large N duality and localization with respect to a degenerate torus action. We also discuss potential generalizations of our formalism to a broader class of Calabi-Yau threefolds using the same underlying principles.
LOW-VALENT TITANIUM REDUCTIVE COUPLING REACTIONS OF PYRRYLALDEHYDES AND PYRRYLKETONES

Abstract 2-Pyrrylaldehydes are shown to react under McMurry conditions to give the expected coupling products in high yield, while 3-pyrrylaldehydes and 3-pyrrylketones give in good yields either rearrangement products or reduced McMurry products, depending upon the nature of the reactant.
Nuclear Stellar Populations in the Infrared Space Observatory Atlas of Bright Spiral Galaxies

To understand the nuclear stellar populations and star formation histories of the nuclei of spiral galaxies, we have obtained K-band nuclear spectra for 41 galaxies and H-band spectra for 20 galaxies in the Infrared Space Observatory’s Atlas of Bright Spiral Galaxies. In the vast majority of the subsample (80%), the near-infrared spectra suggest that evolved red stars completely dominate the nuclear stellar populations and that hot young stars are virtually nonexistent. The signatures of recent star formation activity are only found in 20% of the subsample, even though older red stars still dominate the stellar populations in these galaxies. Given the dominance of evolved stars in most galaxy nuclei and the nature of the emission lines in the galaxies where they were detected, we suggest that nuclear star formation proceeds in the form of instantaneous bursts. The stars produced by these bursts comprise only ! 2% of the total nuclear stellar mass in these galaxies, but we demonstrate how the nuclear stellar populations of normal spiral galaxies can be built up through a series of these bursts. The bursts were detected only in Sbc galaxies and later, and both bars and interactions appeared to be sufficient, but not necessary, triggers for the nuclear star formation activity. The vast majority of galaxies with nuclear star formation were classified as H ii galaxies. With one exception, LINERs and transition objects were dominated by older red stars, which suggested that star formation was not responsible for generating these galaxies’ optical line emission. The nuclear stellar populations of galaxies can reveal important information on the history of nuclear star formation, which could then reveal the mechanisms behind triggering star formation. Understanding nuclear stellar populations is therefore important to understanding the evolution of galaxies and the enhancement of star formation in the universe. Nearinfrared spectroscopy is ideal for studying stellar populations because it traces not only the presence of hot young stars through near-infrared hydrogen recombination lines, such as the Brackett ! line, but also the presence of red stars, particularly red supergiants, and the presence of shocks from supernovae activity. Red supergiants and giants can be determined from the presence of various absorption features in the H and K bands, such as the CO and Si i absorption features in the H band and the CO bands longward of 2.29 " m (Origlia, Moorwood, & Oliva 1993). Supernova activity can be inferred from the presence of Fe ii emission lines associated with the
Board of Director Monitoring and Firm Value in REITs

This article examines the influence of board of director composition and characteristics on real estate investment trust (REIT) shareholder wealth as measured by firm market-to-book ratios. Results...
Electron Acceleration around the Supermassive Black Hole at the Galactic Center

The recent detection of variable infrared emission from Sagittarius A* combined with its previously observed flare activity in X-rays provide compelling evidence that at least a portion of this object's emission is produced by nonthermal electrons. The polarization and variability of Sgr A*'s emission depend strongly on the observed wavelength, indicating distinct physical processes. We show here that acceleration of electrons by plasma wave turbulence in hot gases near the black hole's event horizon can, although with several theoretical uncertainties, reasonably account both for Sgr A*'s millimeter and shorter wavelength emission in the quiescent state and for the infrared and X-ray flares, induced either via an enhancement of the mass accretion rate onto the black hole or by reorganization of magnetic fields coupled to the accretion gas. High-energy electrons diffusing away from the acceleration site toward larger radii might account for Sgr A*'s emission at longer wavelengths. The acceleration model produces prominent IR flares accompanying X-ray bursts. Future coordinated multiwavelength observations will be able to test this model and constrain its parameters.
Method for Full Bloch-Sphere Control of a Localized Spin via a Single Electrical Gate

Manipulating individual spins in semiconductors requires quickly and coherently reorienting localized spins while leaving neighboring spins unaffected. Difficulties confining oscillating magnetic fields have motivated alternate approaches that use electric fields to change the local magnetic environment, including moving an electron within a hyperfine field gradient or fringe-field gradient. Higher temperatures require spins to be localized in much smaller quantum dots, however, where these techniques are less effective. In contrast, g tensor manipulation techniques couple an electric field to the spin via the spin-orbit interaction, and should be scalable to small dots with strong confinement. We describe a device design which permits coherent, non-resonant manipulation of a single electron spin to point in any direction using only a static magnetic field and a single vertical electrical gate.
Effects of Endogenous Task Complexity and the Endowed Bundle on Stated Choice

Abstract Conventionally, studies examining the impacts of choice complexity only consider complexity introduced exogenously from the tasks respondents face. In the context of a stated conjoint survey, this article establishes endogenous complexity measures through decision-makers’ experience known as the endowed bundle before the survey. Results show that complexity should not only be defined exogenously. Endogenous complexity measures are important in determining the utility associated with an alternative and the decision of whether to participate in the market. In addition, some of these complexity effects are nonlinear. We also show that exogenous complexity simultaneous affects the choice consistency. Key Words: Complexity, Endowed Bundle, Random Utility, Stated Choice JEL code: C81, D12 Along with the increasingly popular application of discrete analyses of human choices, literature on various internal design or data collection issues related to these approaches has grown rapidly. Among these issues, considerable attention has been directed to understanding the impacts of choice task complexity on respondents’ decision making. The complexity of choice tasks may be linked to how the tasks are framed, the context of choices, or the cognitive abilities of individuals (Masatlioglu and OK 2005). Swait and