cssi/SciSciGPT-SciSciNet huggingface dataset:
In situ monitoring of quantum conductance in electrodeposited magnetic point contacts

Electrodeposition of Ni over electrodes initially separated by less than 100 nm has made possible the study of the conductance across increasingly smaller gaps between two magnetic materials. In situ measurements of the inter-electrode impedance showed conductance steps at multiples of e2 /h, confirming the absence of spin degeneracy in ferromagnetic nanocontacts. No magnetoresistance larger than 10% for conductance values smaller than 50e2 /h was observed during the contact growth or dissolution under a sweeping external magnetic field.
Massage Therapy Research Review

In this review, massage therapy has been shown to have beneficial effects on varying conditions including prenatal depression, preterm infants, full-term infants, autism, skin conditions, pain syndromes including arthritis and fibromyalgia, hypertension, autoimmune conditions including asthma and multiple sclerosis, immune conditions including HIV and breast cancer and aging problems including Parkinson's and dementia. Although many of the studies have involved comparisons between massage therapy and standard treatment control groups, several have compared different forms of massage (e.g. Swedish versus Thai massage), and different active therapies such as massage versus exercise. Typically, the massage therapy groups have experienced more positive effects than the control or comparison groups. This may relate to the massage therapy providing more stimulation of pressure receptors, in turn enhancing vagal activity and reducing cortisol levels. Some of the researchers have assessed physical, physiological and biochemical effects, although most have relied exclusively on self-report measures. Despite these methodological problems and the dearth of research from the U.S., the massage therapy profession has grown significantly and massage therapy is increasingly practiced in traditional medical settings, highlighting the need for more rigorous research.
Glycosylation using unprotected alkynyl donors.

Gold(III) activation of unprotected propargyl glycosyl donors has been shown to be effective for the synthesis of saccharides. Terminal propargyl glycosides of glucose, galactose, and mannose required heating at reflux in acetonitrile with 5% AuCl3 for reaction with various primary alcohol acceptors, the latter used in 10-fold molar excess relative to donor. Donors containing the 2-butynyl group were more reactive, giving good yields of glycoside products at lower temperatures. Secondary alcohols could also be used but with diminished efficiency. The propargylic family of donors is especially convenient because they can be easily prepared on large scale by Fischer glycosylation and stored indefinitely before chemoselective activation by the catalyst.
"Madelung model" prediction for dependence of lattice parameter on nanocrystal size.

Abstract The competition between the long-range Coulomb attractive and the short-range repulsive interaction in ionic nanocrystals creates an effective negative pressure, which causes the lattice parameter a to increase with decreasing nanoparticle size d. A simple ‘Madelung model’ is used to predict the dependence of the lattice parameter for CeO2 and BaTiO3 on d, δa/a=α/d, for α=0.22 and 0.18 A, respectively. The model predictions are compared with experimental results.
Stochastic parameterization for large eddy simulation of geophysical flows

Recently, stochastic, as opposed to deterministic, parameterizations are being investigated to model the effects of unresolved subgrid scales (SGS) in large eddy simulations (LES) of geophysical flows. We analyse such a stochastic approach in the barotropic vorticity equation to show that (i) if the stochastic parameterization approximates the actual SGS stresses, then the solution of the stochastic LES approximates the "true" solution at appropriate scale sizes; and that (ii) when the filter scale size approaches zero, the solution of the stochastic LES approaches the true solution.
Processes with Inert Drift

We construct a stochastic process whose drift is a function of the process's local time at a reflecting barrier. The process arose as a model of the interactions of a Brownian particle and an inert particle in a paper by Knight [7]. We construct and give asymptotic results for two different arrangements of inert particles and Brownian particles, and construct the analogous process in higher dimensions.
The Pioneer Anomaly and its Implications

The Pioneer 10/11 spacecraft yielded the most precise navigation in deep space to date. However, their radio-metric tracking data has consistently indicated the presence of a small, anomalous, Doppler frequency drift. The drift is a blue-shift, uniformly changing with a rate of ~6 × 10 -9 Hz/s and can be interpreted as a constant sunward acceleration of each particular spacecraft of a P = (8.74 ± 1.33) × 10 -10 m/s 2 . The nature of this anomaly remains unexplained. Here we summarize our current knowledge of the discovered effect and review some of the mechanisms proposed for its explanation. Currently we are preparing for the analysis of the entire set of the available Pioneer 10/11 Doppler data which may shed a new light on the origin of the anomaly. We present a preliminary assessment of such an intriguing possibility.
Bilateral and multilateral exchanges for peer-assisted content distribution

Users of the BitTorrent file-sharing protocol and its variants are incentivized to contribute their upload capacity in a bilateral manner: Downloading is possible in return for uploading to the same user. An alternative is to use multilateral exchange to match user demand for content to available supply at other users in the system. We provide a formal comparison of peer-to-peer system designs based on bilateral exchange with those that enable multilateral exchange via a price-based market mechanism to match supply and demand. First, we compare the two types of exchange in terms of the equilibria that arise. A multilateral equilibrium allocation is Pareto-efficient, while we demonstrate that bilateral equilibrium allocations are not Pareto-efficient in general. We show that Pareto efficiency represents the "gap" between bilateral and multilateral equilibria: A bilateral equilibrium allocation corresponds to a multilateral equilibrium allocation if and only if it is Pareto-efficient. Our proof exploits the fact that Pareto efficiency implies reversibility of an appropriately constructed Markov chain. Second, we compare the two types of exchange through the expected percentage of users that can trade in a large system, assuming a fixed file popularity distribution. Our theoretical results as well as analysis of a BitTorrent dataset provide quantitative insight into regimes where bilateral exchange may perform quite well even though it does not always give rise to Pareto-efficient equilibrium allocations.
Comparative study of the efficacy of four topical anesthetics.

background. With the emergence of new laser and dermatologic procedures, the need for more effective topical anesthesia continues to grow. There are now several topical anesthetics that are being used prior to laser and surgical procedures. objective. To compare the degree and duration of anesthesia produced by four commonly used topical anesthetics, we performed a prospective study investigating the efficacy of EMLA (eutectic mixture of local anesthetics), ELA-Max, 4% tetracaine gel, and betacaine-LA ointment (formerly eutectic-LA). methods. Equal amounts of the above topical anesthetics plus a control (eucerin cream) were applied to 10 test sites under occlusion on the volar forearms of 12 adult volunteers. After a 60-minute application time, the degree of anesthesia was assessed immediately by a Q-switched Nd:YAG laser at 1064 nm. Pain testing was also performed 30 minutes after the 60-minute application period. Volunteer responses to pain stimuli were recorded using an ordinal scale of 0 (no pain) to 4 (maximal pain). The mean scores for the time intervals were obtained. Analysis of the data was performed using analysis of variance (ANOVA), Newman‐Keuls test, Friedman rank order test, and paired t -tests. results. ELA-Max, EMLA, and tetracaine were statistically superior to control after the 60-minute application period. Thirty minutes later, ELA-Max, EMLA, tetracaine, and betacaine-LA were all statistically superior to the control. Comparing individual anesthetics, ELA-Max and EMLA were the superior anesthetics at both time intervals. Although the mean pain scores for each anesthetic were lower 30 minutes after their removal, the differences did not reach statistical significance. conclusion. This is the first prospective study comparing the efficacy of several new topical anesthetic agents. Using the methodology of this study, in which the anesthetics were applied under occlusion, ELA-Max and EMLA were the superior anesthetics after a 60-minute application time and 30 minutes later. In addition, there was a clinical increase in efficacy suggested with all of the anesthetics 30 minutes after their removal. WITH THE EMERGENCE of new laser and surgical techniques, the need for more effective topical anesthesia continues to increase. There are now several topical preparations of local anesthetics that are being used prior to dermatologic procedures. Topical anesthetics block impulse conduction by interfering with the function of sodium channels. By inhibiting sodium flux, the threshold for nerve excitation increases until the ability to generate an action potential is lost. Topical anesthetics are weak bases typically constructed of three important components: an aromatic ring, an intermediatelength ester or amide linkage, and a tertiary amine. Different methods for evaluating and comparing anesthetic efficacy have included venipuncture, 1‐7 pinprick testing, 8 split-thickness skin graft donation, 9‐11
Thermal diffusivity measurements by photothermal laser beam deflection (PTD) : data analysis using the Levenberg-Marquardt algorithm

Abstract Photothermal laser beam deflection (PTD) is a powerful tool used to obtain the thermal diffusivities of bulk solids and thin films. PTD is of special interest for non-destructuve evaluation of bulk, thin film and composite materials anticipated for use in future space missions. Polycrystalline diamond thin films are expected to be useful as heat sinks and thermal conductors in space applications, and measurement of thermal diffusivity in these films is very important. One of the major problems in applying the PTD technique for diffusivity measurements (and hence the thermal conductivity, since heat capacities and densities are not difficult to measure and are frequently known) is that a numerical regression analysis must be performed to simultaneously determine several unknown parameters. Regression is done by matching experimental data with calculations based on analytic models such that an error function is minimized. This paper describes the adaption of the Levenberg-Marquardt algorithm for regression analysis to the determination of thermal diffusivity of bulk and thin film solids by PTD. The analytic theory is reviewd and the numerical analysis method is described. Experimental equipment for high signal-to-noise ratio data is described and data on bulk aluminum taken over a range of frequencies are presented. Regression analysis fits to the theory (performed in an inverse space reference frame) yield values for parameters of the experiment, including the thermal diffusivity.
Mono‐ und Bis(phenyltelluro)methyllithium

Losungen der Titelverbindungen lassen sich aus Bis(phenyltelluro)methan (7) leicht darstellen, das monosubstituierte Li-Derivat durch C6H5Te/Li-Austausch mit Alkyllithium, das disubstituierte durch direkte Metallierung mit Lithium-diisopropylamid. In beiden Fallen wurde dies durch Deuterolyse und Umsetzung mit Elektrophilen bewiesen. Die neuen Tellurderivate werden mit den Schwefel- und Selen-Isologen verglichen. Mono- and Bis(pheyltelluro)methyllithium Solutions of the title compounds are readily prepared from bis(phenyltelluro)methane (7): the monosubstituted one by transmetallative C6H5Te/Li-exchange with alkyllithium, the disubstituted one by direct metalation with lithium diisopropylamide. This was proved in both cases by deuterolysis and derivatization with electrophiles. The new tellurium derivatives are compared with the sulfur and selenium analogues.
Stability analysis of unsteady ablation fronts.

The linear stability analysis of unsteady ablation fronts, is carried out for a semi-infinite uniform medium. For a laser accelerated target, it is shown that a properly selected modulation of the laser intensity can lead to the dynamic stabilization or growth-rate reduction of a large portion of the unstable spectrum. The theory is in qualitative agreement with the numerical results obtained by using the two-dimensional hydrodynamic code ORCHID.
The elastic constants and bond stresses for a three-dimensional composite reinforced by discontinuous fibers

Abstract The bond stress distributions are first determined around a single cylindrical fiber embedded in an infinite matrix which is subjected to uniaxial tension in the direction of the fiber length. This solution is then extended to the case where the matrix is reinforced by a three-dimensional repeating array of fibers. The effective elastic constants and bond stresses are calculated for various fiber-matrix modulus and spacing parameters. In addition, the effects on the stress distributions caused by progressive failure of the bonds between the fibers and matrix are also calculated.
General and specific cognitive deficits in schizophrenia.

Abstract Background It is controversial whether the cognitive deficit in schizophrenia is better characterized as generalized or as reflecting relatively independent deficits in different cognitive domains. The issue has implications for assessment practice, intervention design, and the exploration of schizophrenia genetics. Methods We used a specialized structural equation modeling approach, single common factor analysis, to explore the relative importance of generalized versus independent cognitive deficits in schizophrenia. Eighteen subtest scores from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III were included in the analysis. We analyzed these data for 97 schizophrenia or schizoaffective disorder outpatients and 87 healthy control subjects. Results Approximately two thirds of the overall effect of a schizophrenia diagnosis on cognitive performance was mediated through a single common factor. The Wechsler subtest scores showed almost uniformly strong relationships with this factor. The independent associations of group status with the subtest scores were smaller in magnitude and only selectively significant. Conclusions The relatively greater magnitude of illness effects mediated through the common factor in this analysis, compared with the specific, independent effects, suggests that a generalized cognitive deficit is a core feature of schizophrenia.
Scalar quarkonium and the scalar glueball

Abstract Valence approximation glueball mass and decay calculations support the identification of fJ(1710) as the lightest scalar glueball. An alternate glueball candidate is f0(1500). I present evidence for the identification of f0(1500) as ss quarkonium.
Novel syntheses of 1,3,3-trinitroazetidine

Alternative methods for the synthesis of 1,3,3-trinitroazetidine (TNAZ) from epichlorohydrin, and benzhydrylamine have been developed. These approaches employ N-sulfonyl-3-(hydroxyimino)azetidines as penultimate intermediates and represent an improvement over previously published methods which require either diazo containing intermediates or involve low yielding procedures. Parallel methods employing N-benzhydryl- and N-benzyl-3-(hydroxyimino)azetidine were also investigated as alternate routes to TNAZ.
Art 2-A: an adaptive resonance algorithm for rapid category learning and recognition

Abstract This article introduces Adaptive Resonance Theory 2-A (ART 2-A), an efficient algorithm that emulates the self-organizing pattern recognition and hypothesis testing properties of the ART 2 neural network architecture, but at a speed two to three orders of magnitude faster. Analysis and simulations show how the ART 2-A systems correspond to ART 2 dynamics at both the fast-learn limit and at intermediate learning rates. Intermediate learning rates permit fast commitment of category nodes but slow recoding, analogous to properties of word frequency effects, encoding specificity effects, and episodic memory. Better noise tolerance is hereby achieved without a loss of learning stability. The ART 2 and ART 2-A systems are contrasted with the leader algorithm. The speed of ART 2-A makes practical the use of ART 2 modules in large scale neural computation.
Sieving for mass equidistribution

We approach the holomorphic analogue to the Quantum Unique Ergodicity conjecture through an application of the Large Sieve. We deal with shifted convolution sums as in [Ho109], with various simplifications in our analysis due to the knowledge of the Ramanujan-Petersson conjecture in this holomorphic case.
EXPLORING THE GALAXY MASS−METALLICITY RELATION AT z ∼ 3−5

Long-duration gamma-ray bursts (GRBs) provide a premier tool for studying high-redshift star-forming galaxies thanks to their extreme brightness and association with massive stars. Here we use GRBs to study the galaxy stellar mass-metallicity (M_*-Z) relation at z ~ 3-5, where conventional direct metallicity measurements are extremely challenging. We use the interstellar medium metallicities of long GRB hosts derived from afterglow absorption spectroscopy, in conjunction with host galaxy stellar masses determined from deep Spitzer 3.6 μm observations of 20 GRB hosts. We detect about 1/4 of the hosts with M_(AB)(I) ≈ –21.5 to –22.5 mag and place a limit of M_(AB)(I) ≳ –19 mag on the remaining hosts from a stacking analysis. Using these observations, we present the first rest-frame optical luminosity distribution of long GRB hosts at z ≳ 3 and find that it is similar to the distribution of long GRB hosts at z ~ 1. In comparison to Lyman-break galaxies at the same redshift, GRB hosts are generally fainter, but the sample is too small to rule out an overall similar luminosity function. On the other hand, the GRB hosts appear to be more luminous than the population of Lyα emitters at z ~ 3-4. Using a conservative range of mass-to-light ratios for simple stellar populations (with ages of 70 Myr to ~2 Gyr), we infer the host stellar masses and present mass-metallicity measurements at z ~ 3-5 ((z) ≈ 3.5). We find that the detected GRB hosts, with M_* ≈ 2 × 10^(10) M_☉, display a wide range of metallicities, but that the mean metallicity at this mass scale, Z ≈ 0.3 Z_☉, is lower than measurements at z ≾ 3. Combined with stacking of the non-detected hosts with M_* ≾ 3 × 10^9 M_☉ and Z ≾ 0.1 Z_☉, we find tentative evidence for the existence of an M_*-Z relation at z ~ 3.5 and continued evolution of this relation to systematically lower metallicities from z ~ 2.
A highly stereoselective, novel coupling reaction between alkynes and aldehydes

In the presence of indium triflate or gallium chloride, a novel coupling between internal alkynes and aldehydes occurred to give unsaturated ketones and [4+1] annulation products.
Highly efficient biomimetic total synthesis and structural verification of bistratamides E and J from Lissoclinum bistratum.

The interesting biological activities of heterocycle-containing cyclic peptide-derived natural products, isolated from marine organisms over the past twenty years, have attracted the interest of many synthetic and natural products chemists. Bistratamides E–J, members of this class of natural products that were isolated very recently from Lissoclinum bistratum, exhibited cytotoxic activity against a human colon tumor (HCT-116) cell line. Here we report the first total syntheses of bistratamides E (1) and J (2) in overall yields of 19 and 34 %, respectively. The thiazole substructures have been synthesized by oxidation of their corresponding thiazoline substructures, which were obtained from cysteine containing peptides using a novel biomimetic approach wherein Val-Cys dipeptide units were converted to thiazolines by a bisphosphonium salt. The final macrocyclization was promoted efficiently using the combination of PyBOP and DMAP. This approach allows the use of readily available Fmoc-protected amino acids to make complex thiazole and oxazoline-containing natural products.
New attractors and area codes

In this note we give multiple examples of the recently proposed New Attractors describing supersymmetric flux vacua and non-supersymmetric extremal black holes in IIB string theory. Examples of non-supersymmetric extremal black hole attractors arise on a hypersurface in WP{sub 1,1,1,1,2}{sup 4}. For flux vacua on the orientifold of the same hypersurface existence of multiple basins of attraction is established. It is explained that certain fluxes may give rise to multiple supersymmetric flux vacua in a finite region on moduli space, say at the Landau-Ginzburg point and close to conifold point. This suggests the existence of multiple basins for flux vacua and domain walls in the landscape for a fixed flux and at interior points in moduli space.
Characteristics of the Atlantic Storm-Track Eddy Activity and Its Relation with the North Atlantic Oscillation

Abstract This study focuses on feedbacks of the high-frequency eddy activity onto the quasi-stationary circulation, particularly with regard to the North Atlantic Oscillation (NAO). The methodology consists of analyzing NCEP–NCAR reanalysis data and sensitivity runs from a high-resolution nonhydrostatic regional model. Consistent with recent studies, results show that the jet displacement characteristic of the NAO phenomenon depends strongly on the dynamics of the synoptic-scale waves and the way they break. Positive and negative phases of the NAO are closely related to anticyclonic and cyclonic wave breaking, respectively. Indeed, the high-frequency momentum flux whose sign is directly related to the type of wave breaking is correlated with the NAO index over the Atlantic. The peak of the momentum flux signal precedes that of the NAO by a few days suggesting that wave breaking is triggering NAO events. Two examples illustrate the significant impact of single storms, in particular those occurring in the e...
Dietary Flavonoid Intake and Risk of Cardiovascular Disease in Postmenopausal Women

Flavonoids, a group of phenolic compounds found in fruits and vegetables, are known to have antioxidant properties. They prevent low density lipoprotein oxidation in vitro and thus may play a role in the prevention of coronary heart disease (CHD). In 1986, in a prospective study of 34,492 postmenopausal women in Iowa, the authors examined the association of flavonoid intake with CHD and stroke mortality. Over 10 years of follow-up, 438 deaths from CHD and 131 deaths from stroke were documented. Total flavonoid intake was associated with a decreased risk of CHD death after adjusting for age and energy intake (p for trend = 0.04). This association was attenuated after multivariate adjustment. However, decreased risk was seen in each category of intake compared with the lowest. Relative risks and 95% confidence intervals of CHD death from lowest to highest intake category were 1.0, 0.67 (95% confidence interval (CI) 0.49-0.92), 0.56 (95% CI 0.39-0.79), 0.86 (95% CI 0.63-1.18), and 0.62 (95% CI 0.44-0.87). There was no association between total flavonoid intake and stroke mortality (p for trend = 0.83). Of the foods that contributed the most to flavonoid intake in this cohort, only broccoli was strongly associated with reduced risk of CHD death. The data of this study suggest that flavonoid intake may reduce risk of death from CHD in postmenopausal women.
Fermi velocity engineering in graphene by substrate modification

The Fermi velocity, vF, is one of the key concepts in the study of a material, as it bears information on a variety of fundamental properties. Upon increasing demand on the device applications, graphene is viewed as a prototypical system for engineering vF. Indeed, several efforts have succeeded in modifying vF by varying charge carrier concentration, n. Here we present a powerful but simple new way to engineer vF while holding n constant. We find that when the environment embedding graphene is modified, the vF of graphene is (i) inversely proportional to its dielectric constant, reaching vF ~ 2.5×106 m/s, the highest value for graphene on any substrate studied so far and (ii) clearly distinguished from an ordinary Fermi liquid. The method demonstrated here provides a new route toward Fermi velocity engineering in a variety of two-dimensional electron systems including topological insulators.
Learning Redundant Motor Tasks with and without Overlapping Dimensions: Facilitation and Interference Effects

Prior learning of a motor skill creates motor memories that can facilitate or interfere with learning of new, but related, motor skills. One hypothesis of motor learning posits that for a sensorimotor task with redundant degrees of freedom, the nervous system learns the geometric structure of the task and improves performance by selectively operating within that task space. We tested this hypothesis by examining if transfer of learning between two tasks depends on shared dimensionality between their respective task spaces. Human participants wore a data glove and learned to manipulate a computer cursor by moving their fingers. Separate groups of participants learned two tasks: a prior task that was unique to each group and a criterion task that was common to all groups. We manipulated the mapping between finger motions and cursor positions in the prior task to define task spaces that either shared or did not share the task space dimensions (x-y axes) of the criterion task. We found that if the prior task shared task dimensions with the criterion task, there was an initial facilitation in criterion task performance. However, if the prior task did not share task dimensions with the criterion task, there was prolonged interference in learning the criterion task due to participants finding inefficient task solutions. These results show that the nervous system learns the task space through practice, and that the degree of shared task space dimensionality influences the extent to which prior experience transfers to subsequent learning of related motor skills.
Oligarchic growth with migration and fragmentation

Abstract In the core-accretion model, giant-planet cores form by oligarchic growth from a population of planetesimals prior to the dispersal of the disk gas. Once a core reaches a critical mass of roughly 10 Earth masses, it begins to accrete a gaseous envelope, forming a giant planet. Collisions between planetesimals cause fragmentation. Planetesimal fragments are more easily captured by cores, speeding up growth, but fragments are also lost by radial drift, reducing the total solid mass in the disk. Interaction with the gas causes cores to undergo inward type-I migration. Migration allows a core to accrete planetesimals from a larger region, but migrating cores may be lost if they reach the star. Thus, migration and fragmentation have both a positive and a negative impact on core formation. Here we describe results of new simulations of oligarchic growth that include fragmentation and/or migration. In the absence of migration, cores grow until they reach their isolation mass, which increases with distance from the star, or until the disk gas disperses. Fragmentation increases the maximum core mass by increasing growth rates in the outer disk, allowing objects to reach their isolation mass during the disk lifetime. When migration is present, cores migrate inwards rapidly when they approach 1 Earth mass. Most migrating cores are lost. Migrating cores gain little extra mass since they are passing through regions that have been depleted by earlier generations of cores. For a disk viscosity parameter alpha = 1 e − 3 and planetesimal radius = 10 km, the maximum core mass is roughly 4 and 0.5 Earth masses with/without fragmentation, respectively, with little dependence on the disk mass. Formation and survival of 10-Earth-mass cores, in the presence of migration, requires large alpha ( 1 e − 2 ) and a massive disk (0.1 solar masses). When alpha is large, type-I migration rates decrease rapidly with time, allowing large, late-forming cores to survive. The addition of a stochastic (random-walk) migration component makes little difference to the outcome, provided that stochastic migration affects only cores larger than 0.01 Earth masses. Stochastic migration becomes increasingly important if it also affects lower-mass objects.
Molecular approaches to the photocatalytic reduction of carbon dioxide for solar fuels

The scientific community now agrees that the rise in atmospheric CO2, the most abundant green house gas, comes from anthropogenic sources such as the burning of fossil fuels. This atmospheric rise in CO2 results in global climate change. Therefore methods for photochemically transforming CO2 into a source of fuel could offer an attractive way to decrease atmospheric concentrations. One way to accomplish this conversion is through the light-driven reduction of carbon dioxide to methane (CH4(g)) or methanol (CH3OH(l)) with electrons and protons derived from water. Existing infrastructure already supports the delivery of natural gas and liquid fuels, which makes these possible CO2 reduction products particularly appealing. This Account focuses on molecular approaches to photochemical CO2 reduction in homogeneous solution. The reduction of CO2 by one electron to form CO2•− is highly unfavorable, having a formal reduction potential of −2.14 V vs SCE. Rapid reduction requires an overpotential of up to 0.6 V, du...
EFFECTS OF GRAVITY ON BUBBLE FORMATION IN AN ANNULAR JET

The effects of gravity on the bubble formation in an annular jet were studied. The experiments were conducted in the 2.2-second drop tower at the NASA Glenn Research Center. Terrestrial gravity experiments were conducted at the Fluid Dynamics Research Laboratory at the University of Oklahoma. Stainless steel tubing with inner diameters of 1/8" (gas inner annulus) and 5/16" (liquid outer annulus) served as the injector. A rectangular test section, 6" x 6" x 14" tall, made out of half-inch thick Lexan was used. Images of the annular jet were acquired using a high-speed camera. The effects of gravity and varying liquid and gas flow rates on bubble size, wavelength, and breakup length were documented. In general, the bubble diameter was found to be larger in terrestrial gravity than in microgravity for varying Weber numbers (0.05 - 0.16 and 5 - 11) and liquid flow rates (1.5 ft/s - 3.0 ft/s). The wavelength was found to be larger in terrestrial gravity than in microgravity, but remained constant for varying Weber numbers. For low Weber numbers (0.05 - 0.16), the breakup length in microgravity was significantly higher than in terrestrial gravity. Comparison with linear stability analysis showed estimated bubble sizes within 9% of experimental bubble sizes. Bubble size compared to other terrestrial gravity experiments with same flow conditions showed distinct differences in bubble size, which displayed the importance of injector geometry on bubble formation.
Clusters of Galaxies in the Local Universe

We use a matched filter algorithm to find and study clusters in both N-body simulations artificially populated with galaxies and the Two Micron All Sky Survey (2MASS). In addition to numerous checks of the matched filter algorithm, we present results on the halo multiplicity function and the cluster number function. For a subset of our identified clusters we have information on X-ray temperatures and luminosities that we cross-correlate with optical richness and galaxy velocity dispersions. With all quantities normalized by the spherical radius corresponding to a mass overdensity of ΔM = 200 or the equivalent galaxy number overdensity of ΔN = 200Ω 666, we find that the number of L > L* galaxies in a cluster of mass M200 is log N*666 = (1.44 ± 0.17) + (1.10 ± 0.09) log(M200h/1015 M☉), where the uncertainties are dominated by the scatter created by three choices for relating the observed quantities to the cluster mass. The region inside the virial radius has a K-band cluster mass-to-light ratio of (M/L)K = (116 ± 46)h, which is essentially independent of cluster mass. Integrating over all clusters more massive than M200 = 1014 h-1 M☉, the virialized regions of clusters contain 7% of the local stellar luminosity, quite comparable to the mass fraction in such objects in currently popular ΛCDM models.
Numerical construction of likelihood distributions and the propagation of errors

Abstract The standard method for the propagation of errors, based on a Taylor series expansion, is approximate and frequently inadequate for realistic problems. A simple and generic technique is described in which the likelihood is constructed numerically, thereby greatly facilitating the propagation of errors.
APPLICATIONS OF BENZOTRIAZOLE METHODOLOGY IN HETEROCYCLE RING SYNTHESIS AND SUBSTITUENT INTRODUCTION AND MODIFICATION

Applications of benzotriazole methodology for the preparation of heterocyclic compounds are reviewed. The characteristic advantages of benzotriazole as a synthetic auxiliary are first briefly considered. This is followed by a summary of its use in ring synthesis in which the construction of small; five-membered; six-membered; and larger heterocyclic rings using benzotriazole methodology are each examined separately. Finally, consideration of the use of benzotriazole in the ring annulation - particularly benzannulation - of heterocycles. Subsequent sections deal with the introduction of substituents into aromatic heterocycles; the ring substitution of saturated heterocycles; and benzotriazole assisted modification of heterocyclic substituents. The present review supplements a recent comprehensive review of benzotriazole chemistry [1] which covers the literature through 1996.
Smooth Contact Between a Rigid Indenter and an Initially Stressed Orthotropic Beam

The elastostatics problem of a rigid punch in smooth contact with an initially stressed transversely isotropic layer is investigated. The problem is formulated by writing the field equations in terms of suitable displacement potentials. In addition, an elementary beam theory solution is superimposed on the elasticity solution to satisfy the support boundary conditions for a finite beam. The cases studied are those of a simply supported beam and a clamped beam.
Bernstein-type techniques for 2D free boundary graphs

We prove an a priori bound for the Lipschitz constant of a smooth one-phase free boundary graph F(u) in two dimensions. The function u satisfies an elliptic equation in its positive side, and \(|\nabla u| = 1\) on F(u).
Transfusion-Associated Hepatitis Not Due to Viral Hepatitis Type A or B

Abstract Twenty-two patients who had an episode of transfusion-associated hepatitis not positive for hepatitis B antigen were examined for development of antibody to hepatitis A and B antigens, cytomegalovirus and Epstein-Barr virus. Antibody response to the 27-nm virus-like hepatitis A antigen was measured by immune electron microscopy. In none of the 22 patients studied did serologic evidence of infection with hepatitis A virus develop during the study period. Nine of the 22 patients had antibody responses to cytomegalovirus, but it was difficult to relate these seroconversions to their hepatitis. In addition, all 22 patients had pre-existing antibody to the Epstein-Barr virus. It seems likely that at least a proportion of such antigen-negative transfusion-associated hepatitis is caused by other infectious agents, not yet identified. (N Engl J Med 292:767–770, 1975)
A Model for the Transition Regime in Hypersonic Rarefied Gasdynamics

A two-fluid model for the hypervelocity rarefied regime is presented in this work In contradistinction to the near free molecular theories, which are valid for Kn > 10, the model presented is valid for Kn > 1 To construct the model, an a priori choice of fluids is made Those particles reflected from the surface of the body are considered as the "wall" fluid, whereas all scattered and freestream particles comprise the "cold" fluid; the assumption is that collisions between "wall" and "cold" particles convert "wall" particles to "cold" particles Assuming hard sphere molecules, kinetic models are then constructed for both the "wall" and "cold" fluids Utilizing the kinetic models to compute the collisional moments, a moment method is then employed To close the moment equations for the "wall" fluid, the free molecular distribution function with the number density as state-variable is employed For the "cold" fluid the distribution function is expressed as an expansion in the higher derivatives of the delta function, the expansion parameter being the Mach number of the "cold" fluid The moment equations are then numerically analyzed for the one-dimensional hypersonic compression problem, and numerical results for the relevant quantities are presented
Growth and division--not a one-way road.

Maintaining cell size homeostasis and regulating cell size in response to changing conditions is a fundamental property of organisms. Here we examine the recent advances in our understanding of the interplay between accumulation of mass (growth) and the progression through the cell cycle (proliferation), the coordination of which determines the size of cells. It is well established that growth affects cell division (reviewed in Jorgensen and Tyers, 2004 [1]). This review will focus on the reverse, less well-defined relationship—how cell cycle progression affects growth. We will summarize findings that indicate that growth is not constant during the cell cycle and discuss the surprising possibility that cyclin-dependent kinases (CDKs) inhibit growth.
Upper and lower I/O bounds for pebbling r-pyramids

Modern computers have several levels of memory hierarchy. To obtain good performance on these processors it is necessary to design algorithms that minimize I/O traffic to slower memories in the hierarchy. In this paper, we present I/O efficient algorithms to pebble r-pyramids and derive lower bounds on the number of I/O operations to do so. The r-pyramid graph models financial applications which are of practical interest and where minimizing memory traffic can have a significant impact on cost saving.
Thermal transport through a mesoscopic weak link

We calculate the rate of thermal energy flow between two macroscopic bodies, each in thermodynamic equilibrium at a different temperature, and joined by a weak mechanical link. The macroscopic solids are assumed to be electrically insulating, so that thermal energy is carried only by phonons. To leading order in the strength of the weak link, modeled here by a harmonic spring, the thermal current is determined by a product of the local vibrational density-of-states of the two bodies at the points of connection. Our general expression for the thermal current can be regarded as a thermal analog of the well-known formula for the electrical current through a tunneling barrier. It is also equivalent to the thermal Landauer formula in the weak-tunneling limit. Implications for heat transport experiments on dielectric quantum point contacts are discussed.
Orthogonal polynomials with a resolvent-type generating function

The subject of this paper are polynomials in multiple non-commuting variables. For polynomials of this type orthogonal with respect to a state, we prove a Favard-type recursion relation. On the other hand, free Sheffer polynomials are a polynomial family in non-commuting variables with a resolvent-type generating function. Among such families, we describe the ones that are orthogonal. Their recursion relations have a more special form; the best way to describe them is in terms of the free cumulant generating function of the state of orthogonality, which turns out to satisfy a type of second-order difference equation. If the difference equation is in fact first order, and the state is tracial, we show that the state is necessarily a rotation of a free product state. We also describe interesting examples of non-tracial infinitely divisible states with orthogonal free Sheffer polynomials.
Flows Through Reconstructed Porous Media Using Immersed Boundary Methods

Understanding of the flows through real porous media is of considerable importance given their usage in a wide range of applications. Direct numerical simulations of such flows could be vastly informational but are rarely available in literature owing to the difficulty in simulating flows around complex surface contours that generally constitute porous media. In an effort to better the understanding of such flows, an immersed boundary method (IBM) framework capable of simulating flows through arbitrary surface contours is developed. For simulation of realistic porous media, a stochastic reconstruction procedure based on simulated annealing is utilized. Detailed studies to validate the results are undertaken. Further, numerous calculations are performed on flows through two-dimensional porous channels. The obtained results are compared with the analytical results from Darcy-Forchheimer equation. A study of the effect of varying sizes of the porous structures in such flows shows the increasing deviation from Darcy-Forchheimer equation as the size becomes significant in comparison to the channel height highlighting the need for such a framework and more such DNS studies.Copyright © 2012 by ASME
Hitchhiking through the cytoplasm

We propose an alternative mechanism for intracellular cargo transport which results from motor-induced longitudinal fluctuations of cytoskeletal microtubules (MTs). The longitudinal fluctuations combined with transient cargo binding to the MTs lead to long-range transport even for cargos and vesicles having no molecular motors on them. The proposed transport mechanism, which we call "hitchhiking", provides a possible explanation for the broadly observed yet still mysterious phenomenon of bidirectional transport along MTs. We show that cells exploiting the hitchhiking mechanism can effectively up- and down-regulate the transport of different vesicles by tuning their binding kinetics to characteristic MT oscillation frequencies.
Corporate divestitures and family control

This paper investigates the relationship between divestitures and firm value in family firms. Using hand-collected data on a sample of over 30,000 firm-year observations, we find that family firms are less likely than non-family firms to undertake divestitures, especially when these companies are managed by family rather than non-family-CEOs. However, we then establish that the divestitures undertaken by family firms, predominantly those run by family-CEOs, are associated with higher post-divestiture performance than their non-family counterparts. These findings indicate that family firms may fail to fully exploit available economic opportunities, potentially because they pursue multiple objectives beyond the maximization of shareholder value. These results also elucidate how the characteristics of corporate owners and managers can influence the value that firms derive from their corporate strategies
Stress distribution and mass transport along grain boundaries during steady-state electromigration

Abstract The distribution of normal stress and mass flux in the plane of each grain boundary of a polycrystalline thin-film conductor during electromigration has been calculated, assuming zero grain boundary flux divergence (steady state), for various boundary conditions by standard boundary value methods of diffusion theory. Steady state, representing a balance between the (applied) electric and (induced) stress driving forces, develops after a transient time, which is estimated to be short for the cases considered. Continuity of stress and flux is assumed at the intersection of grain boundaries with each other (triple junctions). Intersections of grain boundaries with the film surfaces are assumed to be of two types: either open (passes flux freely) or closed (zero flux). The bottom film surface (substrate) is assumed closed and the top surface (bare metal) open; grain boundary intersections with the film edges (edge junctions) can be of either type. Several grain boundary configurations and combinations of boundary conditions are considered. The results clearly show accumulation or depletion of matter at open edge junctions and formation of incipient holes and hillocks near the intersection of triple junctions with the top surface. Maximum tensile or compressive stress occurs at the intersections of triple junctions and closed edge junctions with the bottom surface.
Photoelectrochemistry and interfacial energetics of titanium dioxide photoelectrodes in fluoride-containing solutions

Current-potential and ac impedance measurements were used to characterize the semiconductor/solution interface for TiO{sub 2-x} and TiO{sub 2-x}F{sub x} single-crystal electrodes in anhydrous HF/NaF and acetonitrile/tetraethylammonium fluoride (TEAF) solutions. In HF/NaF, photoelectrochemical evolution of elemental fluorine occurs at potentials positive of the flatband potential, E{sub fb}, which is +0.6 V vs the H{sup +}/H{sub 2} formal potential. Photocorrosion occurs readily in this medium with TiO{sub 2-x} but not with TiO{sub 2-x}F{sub x}. No photocurrent is observed even at very positive potentials in acetonitrile/TEAF, and Mott-Schottky plots show that E{sub fb} is {minus}2.10 V vs NHE in this medium and that the valence band-edge potential is therefore negative of the F{sup {minus}}/F{sub 2} formal potential. The ideal photoelectrochemical behavior and low photocorrosion rate observed with TiO{sub 2-x}F{sub x} are attributed to a low density of interband surface states ((3-7) {times} 10{sup 11} cm{sup {minus}2}), tentatively assigned to Ti{sup 3+} deep levels. No oxygen vacancy states are detected at the TiO{sub 2-x}F{sub x} surface, in either HG/NaF or acetonitrile/TEAF, by the ac impedance technique.
TARGET CHARACTERIZATION IN 3D USING INFRARED LIDAR

ABSTRACT We report examples of the use of a scanning tunable CO 2 laser lidar system in the 9-11 m region to construct images ofvegetation and rocks at ranges of up to 5 km from the instrument. Range information is combined with horizontal and verticaldistances to yield an image with three spatial dimensions simultaneous with the classification of target type. Objectclassification is made possible by the distinct spectral signatures of both natural and man-made objects. Several multivariatestatistical methods are used to illustrate the degree of discrimination possible among the natural variability of objects in bo thspectral shape and amplitude.Keywords: lidar, multispectral imaging, matched-filter analysis, vegetation mapping, target detection 1. INTRODUCTION Infrared remote sensing instruments have been developed and applied to many different applications involving imagery of theearths surface. 1 In principle, both passive instruments (detecting reflected or emitted light) and active instruments (usingreflected laser light) can provide such spatial and spectral information, but passive instruments are more widely used becauseof their greater simplicity. In this paper, we demonstrate an application of a multispectral lidar platform to mapping ofvegetation and rock. Active lidar imagery provides three spatial dimensions rather than two, simultaneously with theidentification of the physical target sampled by the laser. At longer wavelengths accessible by a CO