cssi/SciSciGPT-SciSciNet huggingface dataset:
Heliospheric structure: The bow wave and the hydrogen wall

Recent IBEX observations indicate that the local interstellar medium (LISM) flow speed is less than previously thought (23.2 km s–1 rather than 26 km s–1). Reasonable LISM plasma parameters indicate that the LISM flow may be either marginally super-fast magnetosonic or sub-fast magnetosonic. This raises two challenging questions: (1) Can a LISM model that is barely super-fast or sub-fast magnetosonic account for Lyα observations that rely critically on the additional absorption provided by the hydrogen wall (H-wall)? and (2) If the LISM flow is weakly super-fast magnetosonic, does the transition assume the form of a traditional shock or does neutral hydrogen (H) mediate shock dissipation and hence structure through charge exchange? Both questions are addressed using three three-dimensional self-consistently coupled magnetohydrodynamic plasma—kinetic H models with different LISM magnetic field strengths (2, 3, and 4 μG) as well as plasma and neutral H number densities. The 2 and 3 μG models are fast magnetosonic far upwind of the heliopause whereas the 4 μG model is fully subsonic. The 2 μG model admits a broad (~50-75 AU) bow-shock-like structure. The 3 μG model has a smooth super-fast-sub-fast magnetosonic transition that resembles a very broad, ~200 AU thick, bow wave. A theoretical analysis shows that the transition from a super-fast to a sub-fast magnetosonic downstream state is due to the charge exchange of fast neutral H and hot neutral H created in the supersonic solar wind and hot inner heliosheath, respectively. For both the 2 μG and the 3 μG models, the super-fast magnetosonic LISM flow passes through a critical point located where the fast magnetosonic Mach number M = 1 and Qe = γ/(γ – 1)UQm , where Qe and Qm are the plasma energy and momentum source terms due to charge exchange, U is the LISM flow speed, and γ is the plasma adiabatic index. Because the Mach number is only barely super-fast magnetosonic in the 3 μG case, the hot and fast neutral H can completely mediate the transition and impose a charge exchange length scale on the structure, making the solar-wind-LISM interaction effectively bow-shock-free. The charge exchange of fast and hot heliospheric neutral H therefore provides a primary dissipation mechanism at the weak heliospheric bow shock, in some cases effectively creating a one-shock heliosphere (i.e., a heliospheric termination shock only). Both super-fast magnetosonic models produce a sizeable H-wall. We find that (1) a sub-fast magnetosonic LISM flow cannot model the observed Lyα absorption profiles along the four sightlines considered (α Cen, 36 Oph, DK UMa, and χ1 Ori—upwind, sidewind, and downwind respectively); (2) both the super-fast magnetosonic models can account for the Lyα observations, with possibly the bow-shock-free 3 μG model being slightly favored. Subject to further modeling and comparison against further lines of sight, we conclude with the tantalizing possibility that IBEX may have discovered a class of interstellar shocks mediated by neutral H.
The Effective Lagrangian of Three Dimensional Quantum Chromodynamics

We consider the low energy limit of three dimensional quantum chromodynamics (QCD) with an even number of flavors. We show that parity is not spontaneously broken, but the global (flavor) symmetry is spontaneously broken. The low energy effective Lagrangian is a nonlinear sigma model on the Grassmannian. Some Chern-Simons terms are necessary in the Lagrangian to realize the discrete symmetries correctly. We consider also another parametrization of the low energy sector which leads to a three dimensional analogue of the Wess-Zumino-Witten-Novikov model. Since three dimensional QCD is believed to be a model for quantum antiferromagnetism, our effective Lagrangian can describe their long wavelength excitations (spin waves).
Automated quantitative description of spiral galaxy arm-segment structure

We describe a system that builds quantitative structural descriptions of spiral galaxies. This enables translation of sky survey images into data needed to help address fundamental astrophysical questions such as the origin of spiral structure — a phenomenon that has eluded full theoretical description despite 150 years of study. The difficulty of automated measurement is underscored by the fact that, to date, only manually-guided efforts (such as the citizen science project Galaxy Zoo) have been able to extract structural information about spiral galaxies. An automated approach is needed to eliminate measurement subjectivity and handle the otherwise-overwhelming image quantities (up to billions of images) from near-future surveys. Our approach automatically describes spiral galaxy structure as a set of arcs fit to pixel clusters, precisely characterizing spiral arm segment arrangement while retaining the flexibility needed to accommodate the observed wide variety of spiral galaxy structure. The largest existing quantitative measurements were manually-guided and encompassed fewer than 100 galaxies, while we have already applied our method to nearly 30,000 galaxies. Our output is consistent with previous information, both quantitatively over small existing samples, and qualitatively with human classifications.
Relationships between polyphosphate chemistry, biochemistry and apatite biomineralization.

5. Inorganic Polyphosphate Chemistry 4699 5.1. History 4699 5.2. Definition 4699 5.3. Formation 4699 5.4. Hydrolytic Degradation (Hydrolysis) 4699 5.5. Analytical Methods 4700 5.5.1. Chromatography 4700 5.5.2. Hydrolytic Degradation Assay 4700 5.5.3. Titration 4700 5.5.4. Colorimetry 4700 5.5.5. Solubility Fractionation 4700 5.5.6. Gel Electrophoresis 4700 5.5.7. P NMR 4700 5.5.8. Infrared 4700 5.5.9. X-ray Diffraction and X-ray Energy-Dispersive Analysis 4700
Evidence for r-Mode Oscillations in Super-Kamiokande Solar Neutrino Data

There has for some time been evidence of variability in radiochemical solar neutrino measurements, but this evidence has seemed suspect since the Cerenkov experiments have not shown similar evidence of variability. The present reanalysis of Super-Kamiokande data shows strong evidence of r-mode oscillations. The frequencies of these oscillations correspond to a region with a sidereal rotation rate of 13.97 year−1. This estimate is incompatible with the rotation rate in the convection zone but is compatible with current estimates of the rotation rate in the radiative zone. The excitation of r modes in the radiative zone may be due to a velocity field originating in or related to the nuclear-burning core.
Dielectric relaxation in nanopillar NiFe–silicon structures in high magnetic fields

Abstract We explore the dielectric relaxation properties of NiFe nanowires in a nanoporous silicon template. Dielectric data of the NiFe–silicon structure show a strong relaxation resonance near 30 K. This system shows Arrhenius type of behavior in the temperature dependence of dissipation peaks vs. frequency. We report magnetic field dependence of dipolar relaxation rate and the appearance of structure in the dielectric spectrum related to multiple relaxation rates. A magnetic field affects both the exponential prefactor in the Arrhenius formula and the activation energy. From this field dependence we derive a simple exponential field dependence for the prefactor and linear field approximation for the activation energy which describes the data. We find a significant angular dependence of the dielectric relaxation spectrum for regular silicon and nanostructured silicon vs. magnetic field direction, and describe a simple sum rule that describes this dependence. We find that although similar behavior is observed in both template and nanostructured materials, the NiFe–silicon shows a more complex, magnetic field dependent relaxation spectrum.
A View to a Kill: T6SS-Mediated Cell Killing Visualized by Fluorescence Microscopy

The Type Six Secretion System (T6SS) is a bacterial toxin-delivery system targeting bacterial cells which neighbor the donor, promoting recipient cell death. The T6SS is widely conserved among Gram-negative bacteria and may be a central determinant in bacterial fitness in polymicrobial communities of particular relevance to chronic infection. Sequence homology of secretion system components to the T4 bacteriophage tail spike, cryoEM reconstructions of the secretion system and fluorescence imaging are all consistent with a dynamic mechanism of secretion. The complex system, which is composed of at least 15 proteins, forms a puncturing apparatus/delivery system which uses a donor protein filament to puncture the recipient cell wall to deliver protein toxins. Using quantitative imaging analysis of multiple fluorescent fusions, we present a detailed characterization of T6SS system dynamics visualized in single cells in multiple bacterial species, developing a model of T6SS function. We present quantitative measurements of the dynamics of the secretion system - from the assembly to contraction to disassembly - in conjunction with quantitative measures of system function, including recipient cell lysis.
Predicting temperature profiles in producing oil wells using artificial neural networks

A novel approach using artificial neural networks (ANNs) for predicting temperature profiles evaluated 27 wells in the Gulf of Mexico. Two artificial neural network models were developed that predict the temperature of the flowing fluid at any depth in flowing oil wells. Back propagation was used in training the networks. The networks were tested using measured temperature profiles from the 27 oil wells. Both neural network models successfully mapped the general temperature‐profile trends of naturally flowing oil wells. The highest accuracy was achieved with a mean absolute relative percentage error of 6.0 per cent. The accuracy of the proposed neural network models to predict the temperature profile is compared to that of existing correlations. Many correlations to predict temperature profiles of the wellbore fluid, for single‐phase or multiphase flow, in producing oil wells have been developed using theoretical principles such as energy, mass and momentum balances coupled with regression analysis. The N...
Aquation of chloropentaamminecobalt(III) Perchlorate in chloride‐ion containing water–nonaqueous solvent mixtures

The equilibrium quotients for the formation of Co(NH3)5Cl2+ from Co(NH3)5OH23+ and Cl− were 3.74±0.25 M−1 and 6.07±0.54 M−1 at 45.0°C in 10:1 mole ratio water: dimethyl sulfoxide and in 25 w/w % aqueous ethanol, respectively, and those forthe formation of the ion pair Co(NH3)5OH23+ . Cl− were 1.21±0.20 M−1 and 1.58±0.17 M−1, respectively, in the same solvents. The aquation and anation rateconstants were determined at 45.0°C for these two solvents over the range of chloride-ion concentrations 0.0 ≤ [Cl−] ≤ 0.9 M. The aquation rate constant was essentially independent of chloride-ion concentration in each solvent over this range. The inverse of the pseudo-first-order anation rate constant was linearly dependent on the inverse of the chloride-ion concentration in each solvent. The least squares relationships between (1/kan) and (1/[Cl−]) gave intercepts and ratios of intercept to slope which were analyzed interms of Id and D mechanisms. It was concluded that the data were not satisfied by a D mechanism, but that they were consistent with an Id mechanism.
Taxing Under the Influence? : Corruption and U.S. State Beer Taxes

This article examines the effect of state level corruption on state beer taxes in the United States. Our lobby group model predicts that corruption reduces the beer tax, but this effect is conditional on the level of alcohol-related vehicle deaths. Using a panel of state level data from 1982 to 2001, we find that increased corruption is associated with lower state beer tax rates. The magnitude of the effect, however, declines with increases in alcohol-related traffic deaths. Our findings suggest that future empirical work estimating the effect of alcohol taxes on alcohol-related traffic fatalities should treat alcohol taxes as endogenous.
Binuclear schiff base complexes

Abstract Two new binucleating ligands, pentyl-bis(3-(bae)) and octyl-bis(3-(bae)) and their copper(II) and nickel(II) complexes have been prepared and characterized. The binuclear Cu(II) and Ni(II) complexes display magnetic and spectroscopic behavior characteristic of square-planar monomeric compounds. No magnetic exchange interactions between copper centers was detected at either room or liquid nitrogen temperatures. Both of the Cu(II) and Ni(II) ions in these complexes undergo two quasi-reversible one-electron reductions at nearly the same potentials.
Sulfanylation of 1,3-dithiane anions by 5-(alkylsulfanyl)-1-phenyltetrazoles

An unusual reaction between 1,3-dithiane anions and by 5-(alkylsulfanyl)-1-phenyltetrazoles has been discovered in which the dithiane anion formally displaces the 1-phenyltetrazole ring from sulfur to provide a sulfanylated dithiane.
The influence of information presentation order and evaluation time horizon on the outcome effect

Abstract The outcome effect occurs when an evaluation is influenced by knowledge of the outcome, even when it is unclear that the outcome provides additional information about the evaluatee's performance. This phenomenon has received considerable attention in the accounting and psychology literatures, which rely on cognitive or motivational factors to account for the outcome effect. However, prior research has not considered the impact of information presentation order or the evaluation time horizon. We evaluate prior research in accounting and conclude that information presentation order could have significantly impacted the outcome effect observed in these studies. We then report the results of an experiment that provides evidence that information presentation order plays a significant role in the existence and magnitude of the outcome effect. In addition, we find that the length of the evaluation time horizon is positively related to the magnitude of the outcome effect when conditions favor a recency effect.
Commuting, Migration, and Rural‐Urban Population Dynamics

Over the past 25 years social scientists attempting to explain the dramatic changes in the relative distribution of urban and rural population growth have gravitated toward two competing explanations. The regional restructuring hypothesis holds that changes in the spatial distribution of employment opportunities have been dominant whereas the deconcentration hypothesis attributes these changes to changes in residential preferences of workers and consumers. We develop an empirical test of these two explanations based on whether commuting and migration are positively or negatively related after controlling for other economic factors. Our econometric results support the deconcentration hypothesis.
Technicolor at criticality

We discuss an asymptotically non-free, natural model for dynamical electroweak symmetry breaking characterized by the emergence of a weakly coupled Higgs in the IR regime. Due to the large anomalous dimension of the Higgs operator, the model is capable of solving the hierarchy problem without losing the phenomenologically appealing features typical of weakly coupled Higgs sectors.
Requirements for the optical insertion of thermal references sources

Thermal radiation sources are often used in thermal imaging sensors as reference sources for offset equalization and gain normalization of the infrared detecting elements. For best results, the `t-number' by which the detector elements view these sources must be exactly equal to that with which they view the external scene. If the t-numbers for different detecting elements are not the same, the result will be inaccurate offset equalization and imperfect gain normalization. The relationship between the scene temperature, reference source temperature, and t-number differences are derived. Quantitative values for the errors in gain and level normalization are calculated.
Fasting induces ketoacidosis and hypothermia in PDHK2/PDHK4-double-knockout mice

The importance of PDHK (pyruvate dehydrogenase kinase) 2 and 4 in regulation of the PDH complex (pyruvate dehydrogenase complex) was assessed in single- and double-knockout mice. PDHK2 deficiency caused higher PDH complex activity and lower blood glucose levels in the fed, but not the fasted, state. PDHK4 deficiency caused similar effects, but only after fasting. Double deficiency intensified these effects in both the fed and fasted states. PDHK2 deficiency had no effect on glucose tolerance, PDHK4 deficiency produced only a modest effect, but double deficiency caused a marked improvement and also induced lower insulin levels and increased insulin sensitivity. In spite of these beneficial effects, the double-knockout mice were more sensitive than wild-type and single-knockout mice to long-term fasting, succumbing to hypoglycaemia, ketoacidosis and hypothermia. Stable isotope flux analysis indicated that hypoglycaemia was due to a reduced rate of gluconeogenesis and that slightly more glucose was converted into ketone bodies in the double-knockout mice. The findings establish that PDHK2 is more important in the fed state, PDHK4 is more important in the fasted state, and survival during long-term fasting depends upon regulation of the PDH complex by both PDHK2 and PDHK4.
Palladium-catalyzed negishi cross-coupling reactions of unactivated alkyl iodides, bromides, chlorides, and tosylates.

A single method (2% Pd2(dba)3/8% PCyp3/NMI in THF/NMP at 80 °C; Cyp = cyclopentyl) achieves the cross-coupling of a range of β-hydrogen-containing primary alkyl iodides, bromides, chlorides, and tosylates with an array of alkyl-, alkenyl-, and arylzinc halides. The process is compatible with a variety of functional groups, including esters, amides, imides, nitriles, and heterocycles.
Prolonged intracerebral infection with poliovirus in asymptomatic mice

A heretofore unrecognized prolonged asymptomatic infection has been identified in mice intracerebrally inoculated with Lansing strain type II poliovirus. Virus was detected by infectivity assay and nucleic acid hybridization and was found in brains as long as 77 days after injection. Viral RNA replication occurred, indicating that persisting virus was not an inactive residuum of the infecting dose. Virus was sometimes found by infectivity even when viral RNA could not be demonstrated by hybridization, but detection by nucleic acid hybridization alone never occurred. Among 56 animals--including mice that died of infection, mice with prolonged infection, and survivors from which virus was not recovered--no animal had a serum neutralization titer above 1:2 in a plaque reduction assay Moreover, brain homogenates of 30 survivors without virus did not have neutralization titers above 1:4 in the plaque reduction assay. These findings were the same as in mock-infected mice.
Generalization of Sturm-Liouville theory to a system of ordinary differential equations with Dirac type spectrum

The Sturm-Liouville theory is generalized to Dirac-equation-like systems of ordinary differential equations. It is shown how the comparison theorem and conversion to integral equations can be generalized.
A sub-sampling digital PM/AM noise measurement system

A digital phase/amplitude modulation (PM/AM) noise-measurement system (DNMS) implementing field-programmable gate array (FPGA)-based digital down-converters (DDCs), and 250 MHz analog-to-digital converters (ADCs) is reported. Performance in the first, baseband Nyquist region shows white phase-noise floors of less than −180 dBc/Hz. With proper pre-filtering of the input signals to prevent undesired aliasing, high-bandwidth track-and-hold amplifiers (THA) extend the operating range of the DNMS to microwave frequencies. Preliminary testing with an 18 GHz THA shows residual white phase-noise floors at 10 GHz of less than −160 dBc/Hz.
Electromotive Forces and the Meissner Effect Puzzle

In a voltaic cell, positive (negative) ions flow from the low (high) potential electrode to the high (low) potential electrode, driven by an ‘electromotive force’ which points in opposite direction and overcomes the electric force. Similarly in a superconductor charge flows in direction opposite to that dictated by the Faraday electric field as the magnetic field is expelled in the Meissner effect. The puzzle is the same in both cases: what drives electric charges against electromagnetic forces? I propose that the answer is the same in both cases: kinetic energy lowering, or ‘quantum pressure.’
Restricted Dumont Permutations

We analyze the structure and enumerate Dumont permutations of the first and second kinds avoiding certain patterns or sets of patterns of length 3 and 4. Some cardinalities are given by Catalan numbers, powers of 2, little Schroder numbers, and other known or related sequences.
Why is there a minimum in projected warming in the tropical North Atlantic Ocean

[1] In IPCC projections for the 21st Century, the sea surface temperature (SST) shows several regions of minimum warming in the tropical oceans. These patterns appear both in fully coupled ocean-atmosphere general circulation models (GCMs) and also in atmospheric GCMs coupled to mixed-layer ocean models, and are robust across a multi-model ensemble. The present study focuses on the minimum warming in the tropical North Atlantic, as it has implications for the influence of greenhouse gas-induced climate change on hurricane development. The surface heat budget is analyzed in order to determine the causes for this minimum warming. It is found that the primary contribution is through the influence of the climatological mean wind speed on the efficiency of latent heat flux. In regions of high wind speed, radiative heating can be balanced by latent heat flux with a smaller change in SST than in other regions of the tropics.
Optical fiber tips functionalized with semiconductor photonic crystal cavities

We develop a new method to transfer photonic crystal resonators to the tips of optical fibers. High Q (2000–4000) cavities are coupled via transmission or PL emission to the fibers in both Si and GaAs.
A Simple Proof of Gopakumar-Vafa Conjecture for Local Toric Calabi-Yau Manifolds

We prove Gopakumar-Vafa conjecture for local toric Calabi-Yau manifolds. It is also proven that the local Gopakumar-Vafa invariants of a given class vanish at large genera.
Independent Signaling Achieves the Capacity Region of the Gaussian Interference Channel With Common Information to Within One Bit

The interference channel with common information (IC-CI) consists of two transmit-receive pairs that communicate over a common noisy medium. Each transmitter has an individual message for its paired receiver, and additionally, both transmitters have a common message to deliver to both receivers. In this paper, through explicit inner and outer bounds on the capacity region, we establish the capacity region of the Gaussian IC-CI to within a bounded gap of one bit, independently of the values of all channel parameters. Using this constant-gap characterization, the generalized degrees of freedom (GDoF) region is determined. It is shown that the introduction of the common message leads to an increase in the GDoF over that achievable over the Gaussian interference channel without a common message, and hence to an unbounded improvement in the achievable rate. A surprising feature of the capacity-within-one-bit result is that most of the available benefit (i.e., to within one bit of capacity) due to the common message is achieved through a simple and explicit coding scheme that involves independent signaling at the two transmitters so that, in effect, this scheme forgoes the opportunity for transmitter cooperation that is inherently available due to shared knowledge of the common message at both transmitters.
Perspective on “The activated complex in chemical reactions”

A general theory of the absolute rates of chemical reactions proved to be an elusive goal for nineteenth century chemists. This goal would only be achieved through a combination of statistical mechanics with the new quantum mechanics of the early twentieth century, when the insights of Henry Eyring and his contemporaries lead to the absolute rate equation that we are only now beginning to rigorously evaluate. The conceptual focus of absolute rate theory is the transition state (or activated complex), the window through which the future plunges into the past, and this is still the foundation of our understanding of chemical reaction rates as we enter the new millennium.
Mathematical modeling for the design of porous coronary stents: nano- and microporous stents v. macroporous stents

Drug delivery polymers play a role in late in-stent thrombosis of first generation drug-eluting coronary stents (DES) via an inflammatory reaction, which contributes to delayed endothelialization seen in patients with late stent thrombosis. Subsequent generation DES have non-polymer based DES whose surface pores serves as a drug reservoir. While drug elution for pores in the nanometer range have been shown to be comparable to polymer-based DES in terms of luminal renarrowing (i.e restenosis), how different pore sizes effect drug elution has not been fully characterized. We hypothesized that drug elution can be characterized with a mathematical model that takes into account the pore size of the stents and molecular characteristics of the eluted drug. Structural data from porous, non-polymer based stents were examined with pore radius ranging from the nanoporous to macroporous range (5 nm to > 10 mm). All stents eluted tacrolimus, sirolimus or paclitaxel. A mathematical model based on Stefan-Maxwell equations describing the mass transport of molecules through a porous media was constructed. A dimensionless number was derived characterizing molecular flux of the drugs through a porous membrane. It was observed that there was exponential rise in molecular flux of the eluted drug with pore sizes greater than 5 micrometers. The molecular characteristics of the eluted drug did not affect the molecular flux. In conclusions, stents in the nano- and microporous range will have similar drug elution profiles while macroporous stents will vary greatly. Careful attention to pore size may significantly enhance the design and efficacy of porous polymer free stents.
Photodynamic therapy (PDT) with endoscopic ultrasound for the treatment of esophageal cancer

In 1995, PDT was approved for palliative use in patients with esophageal cancer. We report our experience using PDT to treat esophageal cancer patients previously treated with combination chemotherapy and radiation therapy. In our series, nine patients referred for PDT with persistent esophageal cancer after chemo-radiation therapy. We found: (1) All patients were men with a mean age of 63 years and eight out of nine had adenocarcinoma with Barrett's esophagus; (2) All patients required endoscopic dilation after PDT; (3) At a mean follow up of 4 months, two T2N0 patients had no demonstrable tumor and all three T3N0 patients had greater than 50% tumor reduction (the partially responsive T3N0 patients will be offered repeat PDT); (4) Patients with metastatic disease (T3N1 or M1) had effective dysphagia palliation. Thus, PDT is safe and effective in ablating all or most tumor in patients with persistent esophageal cancer after chemotherapy and radiation therapy.
Absorber height effects on SWA restrictions and shadow LER

In this study, we look at the 3D effects of absorber height on mask patterns for extreme-ultraviolet lithography (EUVL). Our first consideration is the extent to which sidewall angle (SWA) constrains the process window. Taking 10% of the total CD error budget as an acceptable tolerance, this amounted to 0.2nm of tolerable SWA-induced CD error. Results for the three nominal SWA cases show that the angle needs to be constrained to within about 0.5 degrees. Overall, the results above indicate that not only is there not much change in sensitivity on changing angle as a function of nominal angle, but also that the nominal angle has no large effect on process window size. Secondly, we consider how off-axis illumination shadowing of the mask absorber pattern effects line-edge-roughness (LER). Data suggests shadowing causes minimal differences between the left- and right-side LER for the 22nm half-pitch node under disk σ = 0.5 illumination and 70nm absorber height. For 16nm half-pitch with crosspole σ = 0.2, significant differences were seen.
Surface-gravity determinations for main- sequence B stars.

Main sequence B stars surface gravity determinations from comparison between model atmosphere computed and observed H gamma line equivalent widths
Reflections on the revolutionary wave in 2011

The “Arab Spring” was a surprising event not just because predicting revolutions is a difficult task, but because current theories of revolution are ill equipped to explain revolutionary waves where interactive causal mechanisms at different levels of analysis and interactions between the units of analysis predominate. To account for such dynamics, a multidimensional social science of revolution is required. Accordingly, a meta-framework for revolutionary theory that combines multiple levels of analysis, multiple units of analysis, and their interactions is offered. A structured example of theory building is then given by detailing how the development of world cultural models and practices challenge existing political structures, affect mobilization processes, and make diffusion more likely. A structured example of study design using qualitative comparative analysis of 16 Middle Eastern and North African countries provides support for the interaction of subnational conditions for mobilization, state-centered causes, and transnational factors, including a country’s linkage to world society, as one explanation of the Revolutions of 2011.
Dynamic Internet overlay deployment and management using the X-bone

Abstract The X-Bone dynamically deploys and manages Internet overlays to reduce configuration effort and increase network component sharing. The X-Bone discovers, configures, and monitors network resources to create overlays over existing IP networks. Overlays are useful for deploying overlapping virtual networks on shared infrastructure and for simplifying topology. The X-Bone extends current overlay management by adding dynamic resource discovery, deployment, and monitoring, and allows network components (hosts, routers) to participate simultaneously in multiple overlays. Its two-layer IP in IP tunneled overlays support existing applications and unmodified routing, multicast, and DNS services in unmodified host operating systems. This two-layer scheme uniquely supports recursive overlays, useful for fault tolerance and dynamic relocation. The X-Bone uses multicast to simplify resource discovery, and provides secure deployment as well as secure overlays. This paper presents the X-Bone architecture, and discusses its components and features, and their performance impact.
Negative Ion Photoelectron Spectroscopy Studies of Organic Reactive Intermediates

Nearly 100 years ago, Moses Gomberg introduced the scientific community to the study of organic radicals,1 concluding this classic manuscript with the comment that, “This work will be continued and I wish to reserve the field for myself.” Gomberg’s studies of triphenylmethyl radical were only the beginning of intense research into the properties of the newly discovered trivalent carbon, and despite Gomberg’s proclamation, work was carried out by scientists all over the world. By the middle of the century, new experimental techniques such as matrix isolation2 and flash photolysis3 allowed for the direct spectroscopic study of these transient species. Armed with this array of new tools, in 1964 Porter and Ward politely requested,4 in reference to Gomberg, that “after the respectable period of more than half of a century, we may perhaps be permitted to look further into the problem”. With this comment, they ushered in the modern era of organic radical spectroscopy. Since that time, spectroscopic studies using techniques, including infrared, visible and ultraviolet absorption spectroscopy, Raman spectroscopy, and electron spin resonance spectroscopy, have lead to a much better understanding of the physical properties of many reactive intermediates, including carbenes and radicals. Over the past decade, we have applied the technique of negative ion photoelectron spectroscopy (NIPES) to such systems. In this gas-phase experiment, a beam of mass-selected negative ions is intersected with an intense ultraviolet laser beam, resulting in photodetachment of an electron (Figure 1). A portion of the photodetached electrons are collected and energy-analyzed, giving the photoelectron spectrum, which is a plot of the number of photoelectrons detected as a function of electron kinetic energy (eKE). It is frequently useful to plot the number of electrons versus electron binding energy (eBE), the difference between the laser energy and eKE. The advantage of such a plot is that the positions of features observed in the spectrum are not dependent on the energy of the laser used in the experiment. The information that can be obtained from negative ion photoelectron spectroscopy studies is multifold. Accurate values of vibrational frequencies for the isolated, gas-phase molecule can be determined from vibrational progressions observed in the spectra. Moreover, vibrational frequencies for negative ions can often be obtained from the positions of “hot bands”, i.e., transitions from excited vibrational states of the ion. However, the most important information obtained from photoelectron spectra often turns out to be the electron affinity and electronic state term energies for the neutral intermediate. Electron affinities are of particular value in calculating bond dissociation energies, as illustrated in the thermochemical cycle shown in eq 1. If the gas-phase acidity of a molecule
A Convex Cutting Plane Algorithm for Global Solution of Generalized Polynomial Optimal Design Models

Global optimization algorithms for generalized polynomial design models using a global feasible search approach was discussed in a previous article. A new convex cutting plane algorithm (CONCUT) based on global feasible search and with improved,performance is presented in this sequel article. Computational results of the CONCUT algorithm compared to one using linear cuts (LINCUT) are given for various test problems. A speed reducer design example illustrates the application of the algorithms.
Toward a theory of the perceived spatial layout of scenes

Abstract When normally sighted people observe a natural scene, their perceptions include seeing the supporting ground surface and the arrangements of the objects on that surface: where each object is in relation to the others, to the ground surface, and to the observer. This is defined as the perceived layout of a scene. Most current perceptual theories do not consider perceived layout, preferring to focus on the much narrower concern of perceived radial distance of objects from the observer, ignoring concern for the relationships among the objects of the scene, and among the observer in relation to the objects. In contrast, current cognitive theories have focused on cognitive maps as a spatial representation of scenes previously seen, maps which include explicit representation of spatial layout. However, cognitive theories have paid little theoretical attention to the spatial relationships in scenes currently on view, so they can tell us little about perceived layout, only remembered layout. Perceived layout has been missing from perceptual theories, and needs to be studied in its own right. In addition, to understand spatial cognition, cognitive maps, or any kind of representation of knowledge about the layout of space, we must study the properties of perceived layout—the perception of the arrangements of objects in a scene currently on view. To provide an example of the assessment of perceived layout, experimental data are presented on the psychophysical measurement of the perceived layout of a natural scene containing 13 objects arranged on a large flat lawn. Subjects are asked to draw a map of the scene, to estimate the absolute interobjects distances between every pair of objects in feet, and to compare the relative magnitudes of every possible triplet of interobject distances. The matrices of the interobject distances derived from each of these three measures produce highly reliable and consistent 2-dimensional constructions of the scene through a multi-dimensional scaling analysis. These constructions resemble the physical layout of the actual scene quite closely. However, subjects tend to underestimate the distances between objects when the direction of the distances are parallel to their line of sight, compared to directions perpendicular to their line of sight. Not only does this tend to produce perceived layouts of the scene that are slightly more ellipical than in actuality, but more important, it means that subjects' perceived layouts change when they move to new viewing positions. These analyses and others are used to examine the usefulness and validity of these measures as indices of perceived layout. Following the psychophysical descriptions of the measures, as theoretical analysis of some of the properties of the perceived layout of space is provided, along with a consideration of some of the variables that are expected to affect these properties. The paper concludes with a return to the theoretical issues concerning the contents of a proper theory of space perception.
Construction of Water-Soluble Phosphines, New Advances in Aqueous Organometallic Chemistry

Interest in aqueous organometallic chemistry stems from the fact that water-soluble transition metal compounds have found applications as catalysts in commercially-viable industrial processes for bulk and fine chemicals synthesis and also for their continued utility in biomedicine. As a solvent, water is unique because it displays polar and protic properties. The strong propensity of water to involve in hydrogen bonding interactions and its ability to act as a donor ligand to transition metals makes it even more unique, non-toxic and environmentally-benign, medium for chemical and biological use. In order to make the best use of some of the properties of water as a solvent, it is important that the transition metal complexes exhibit high solubility and good kinetic stability (in some instances) in water. Traditionally, phosphines functionalized with charged/polar substituants (e.g. -SO3H, -COOH or -OH) have been used as ligands to produce aqueous-soluble transition metal complexes. Recently, studies in ou...
Understanding the electro-catalytic oxidation mechanism of urea on nickel electrodes in alkaline medium

Abstract In this paper, the electrocatalytic behavior of urea oxidation on a nickel electrode in alkaline medium was investigated using various electrochemical techniques: cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating disc electrode voltammetry (RDE). Possible mechanisms have been proposed on the basis of the cyclic voltammetry data. The urea oxidation current shows a strong dependence on the concentration of urea and potassium hydroxide that enables the experimental determination, by Tafel studies, of the kinetic reaction orders for the oxidation of urea. The Tafel studies show reaction orders of 0.3 and 2, with respect to urea and OH − concentrations, respectively. The diffusion coefficient of urea was found to be 0.85 × 10 −5 cm 2 s −1 . The presence of a mixed-controlled process (diffusion and kinetics) was confirmed for the oxidation of urea.
Variable stars in the core of the globular cluster M3

We present the results of a survey for variable stars in the core of the globular cluster M3. Our findings include the discovery of 11 new or suspected variables, including a possible W Vir, and the first period determinations for 13 previously known variables.
The physical properties and detectability of reionization-epoch galaxies

We present predictions drawn from cosmological hydrodynamic simulations for the physical, photometric and emission-line properties of galaxies present during the latter stages of reionization from z = 9 to 6. We find significant numbers of galaxies that have stellar masses exceeding 10 9 M ⊙ during this epoch, with metallicities exceeding one-thirtieth solar. Far from primeval 'first-star' objects, these objects exhibit a significant Balmer break, are likely to have reionized their infall regions prior to z = 9, are dominated by atomic rather than molecular cooling and are expected to be forming few if any metal-free stars. By z = 6, the space density of M* > 10 10 M ⊙ objects is roughly equivalent to that of luminous red galaxies today. Galaxies exhibit a slowly evolving comoving autocorrelation length from z = 9 to 6, continuing a trend seen at lower redshifts in which the rapidly dropping bias counteracts rapidly increasing matter clustering. These sources can be marginally detected using current instruments, but modest increases in sensitivity or survey area would yield significantly increased samples. We compare to current observations of the z ≈ 6 rest-ultraviolet and Lya line luminosity functions, and find good agreement. We also compare with the z ∼ 7 object observed by Egami et al., and find that such systems are ubiquitous in our simulations. The intrinsic Lya luminosity function evolves slowly from z = 9 to 6, implying that it should also be possible to detect these objects with upcoming narrow-band surveys such as Dark Ages z Lya Explorer (DAzLE), if as we argue the detectability of Lya does not drop significantly to higher redshifts. We make predictions for near-infrared surveys with the James Webb Space Telescope, and show that while a high density of sources will be found, Population III objects may remain elusive. We present and compare simulations with several recipes for superwind feedback, and show that while our broad conclusions are insensitive to this choice, a feedback model based on momentum-driven winds is mildly favoured in comparisons with available data.
Examining the behavioral manifestations of fan avidity in sports marketing

Purpose – The sports industry is one of the fastest growing business sectors in the world today and its primary source of revenue is derived from fans. Yet, little is known about fans' allocation of time, effort, and/or financial expenditures in regard to the sports they care so desperately about. The purpose of this paper is to explore the multidimensional aspects of such manifestations of fan avidity and examine the nature of heterogeneity of such expressions.Design/methodology/approach – Data were collected from a student sample of football fans from a well‐known US university.Findings – In total, 35 different expressions of fan avidity are developed related to how fans follow and support their favorite team. A spatial choice multidimensional scaling model is developed to uncover four latent dimensions of fan avidity expression.Originality/value – The managerial aspects of these empirical findings are provided, and the authors suggest several directions for future research.
A construction of lattice chiral gauge theories

Abstract Path integration over Euclidean chiral fermions is replaced by the quantum mechanics of an auxiliary system of non-interacting fermions. Our construction avoids the no-go theorem and faithfully maintains all the known important features of chiral fermions, including the violation of some perturbative conservation laws by gauge field configurations of non-trivial topology.
Some topics in analysis of boolean functions

This article accompanies a tutorial talk given at the 40th ACM STOC conference. In it, we give a brief introduction to Fourier analysis of boolean functions and then discuss some applications: Arrow's Theorem and other ideas from the theory of Social Choice; the Bonami-Beckner Inequality as an extension of Chernoff/Hoeffding bounds to higher-degree polynomials; and, hardness for approximation algorithms.
Fake projective planes

A fake projective plane is a complex surface different from but has the same Betti numbers as the complex projective plane. It is a complex hyperbolic space form and has the smallest Euler Poincare characteristic among smooth surfaces of general type. The first example was constructed by Mumford. Later on two more examples were found by Ishida and Kato. A fourth possible one was recently proposed by Keum. In a recent joint work with Gopal Prasad, we showed that there are seventeen non-empty classes of fake projective planes and there can at most be four more specific classes. Higher dimensional analogues and examples were also obtained. The main purpose of the talk is to explain the joint work with Prasad and other related results such as arithmeticity of the lattices involved obtained earlier by Klingler and Yeung independently.
A novel cyclization to isoxazolo[3,4-e][2,1]benzisoxazole

Methylation of 2,1-benzisoxazole 4,5-dione 4-oxime 2 using dimethyl sulfate in DMF and in the presence of potassium carbonate gave a substantial yield of isoxazolo[3,4-e][2,1]benzisoxazole 4 by an unexpected cyclization reaction of the O-methylation product 3.
Forward detectors around the CMS interaction point at LHC and their physics potential

Forward physics with CMS at the LHC covers a wide range of physics subjects, including very low- x B j QCD, underlying event and multiple interactions characteristics, γ -mediated processes, shower development at the energy scale of primary cosmic ray interactions with the atmosphere, diffraction in the presence of a hard scale and even MSSM Higgs discovery in central exclusive production. We describe the forward detector instrumentation around the CMS interaction point and present selected feasibility studies to illustrate their physics potential.
Hydrothermal synthesis and crystal structure of a new inorganic/organic hybrid of scandium sulfate: (H2en)Sc2(SO4)4·(H2O)0.72

Abstract The first organically templated layered structure of scandium sulfate, (H2en)Sc2(SO4)4·(H2O)0.72, (en=ethylenediamine) was synthesized by a hydrothermal method and characterized by single crystal X-ray diffraction. In the title compound, scandium ions are bridged by sulfate groups with a ratio of 1:2 into a 436 layer structure. These layers are parallel packed and separated from each other by ethylenediammonium dications and water molecules. The title compound crystallizes in the monoclinic space group P2/c, with cell parameters a = 8.5966 ( 13 ) A , b = 5.1068 ( 8 ) A , c = 18.847 ( 3 ) A , β = 91.210 ( 3 ) ° , V = 827.2 ( 2 ) A 3 and Z = 2 . Refinement gave R1[I>2σ(I)]=0.0354 and wR2[I>2σ(I)]=0.0878. Thermogravimetric analysis indicates that this material is thermally stable to above 400 °C.
Mating-type gene switching in Saccharomyces cerevisiae

▪ Abstract Saccharomyces cerevisiae can change its mating type as often as every generation by a highly choreographed, site-specific recombination event that replaces one MAT allele with different DNA sequences encoding the opposite allele. The study of this process has yielded important insights into the control of cell lineage, the silencing of gene expression, and the formation of heterochromatin, as well as the molecular events of double-strand break-induced recombination. In addition, MAT switching provides a remarkable example of a small locus control region—the Recombination Enhancer—that controls recombination along an entire chromosome arm.
Turbulence in the Star-forming Interstellar Medium: Steps toward Constraining Theories with Observations

Increasingly sophisticated observational tools and techniques are now being developed for probing the nature of interstellar turbulence. At the same time, theoretical advances in understanding the nature of turbulence and its effects on the structure of the ISM and on star formation are occurring at a rapid pace, aided in part by numerical simulations. These increased capabilities on both fronts open new opportunities for strengthening the links between observation and theory, and for meaningful comparisons between the two.