cssi/SciSciGPT-SciSciNet huggingface dataset:
A one-dimensional numerical model for diesel particulate trap performance study during loading and regeneration

A one-dimensional model was developed for honeycomb diesel particulate traps. Quasi-steady state conservation equations of mass and momentum were solved by combining the shooting method and Runge-Kutta method to find the flow velocity and particulate thickness. A filtration model based on the 'unit collector' filtration theory was used to determine the transient filtration parameters of the porous wall. Transient conservation equations of energy were solved using a fully implicit finite difference method to find the temperature field. Analytical method and experimental data from literature were used to calibrate and validate the model, and good agreement has been achieved. A U-shaped particulate layer thickness distribution was found for a clean trap loading. In the loading process of a catalysed trap, the pressure drop increases with time at the beginning, then decreases but cannot be predicted by numerical models assuming uniform particulate layer distribution. The trap regeneration performances were studied using this model. It was found that initially retained particulate matter can be oxidized completely during controlled regeneration, while a small amount of particulate still remains at the entrance of inlet channel after uncontrolled regeneration. Parametric studies have been carried out and these show that the trap geometry does not significantly affect trap regeneration behaviour. (A)
Lubricating oil and fuel contributions to particulate matter emissions from light-duty gasoline and heavy-duty diesel vehicles.

Size-resolved particulate matter emissions from heavy-duty diesel vehicles (HDDVs) and light-duty gasoline vehicles (LDGVs) operated under realistic driving cycles were analyzed for elemental carbon (EC), organic carbon (OC), hopanes, steranes, and polycyclic aromatic hydrocarbons. Measured hopane and sterane size distributions did not match the total carbon size distribution in most cases, suggesting that lubricating oil was not the dominant source of particulate carbon in the vehicle exhaust. A regression analysis using 17α(H)-21β(H)-29-norhopane as a tracer for lubricating oil and benzo[ghi]perylene as a tracer for gasoline showed that gasoline fuel and lubricating oil both make significant contributions to particulate EC and OC emissions from LDGVs. A similar regression analysis performed using 17α(H)-21β(H)-29-norhopane as a tracer for lubricating oil and flouranthene as a tracer for diesel fuel was able to explain the size distribution of particulate EC and OC emissions from HDDVs. The analysis show...
Oxidation Resistant Germanium Nanowires: Bulk Synthesis, Long Chain Alkanethiol Functionalization, and Langmuir−Blodgett Assembly

A simple method is developed to synthesize gram quantities of uniform Ge nanowires (GeNWs) by chemical vapor deposition on preformed, monodispersed seed particles loaded onto a high surface area silica support. Various chemical functionalization schemes are investigated to passivate the GeNW surfaces using alkanethiols and alkyl Grignard reactions. The stability of functionalization against oxidation of germanium for various alkyl chain lengths is elucidated by X-ray photoelectron spectroscopy. Among all schemes tested, long chain alkanethiols (> or = C12) are found to impart the most stable GeNW passivation against oxidation upon extended exposure to ambient air. Further, the chemically functionalized oxidation-resistant nanowires are soluble in organic solvents and can be readily assembled into close-packed Langmuir-Blodgett films potentially useful for future high performance electronic devices.
Synthesis of Conformationally Restricted Carbocyclic Nucleosides: The Role of the O(4′)-Atom in the Key Hydration Step of Adenosine Deaminase

Conformationally restricted carbocyclic nucleosides with either a northern(N)-type conformation, i.e., N-type 2′-deoxy-methanocarba-adenosine 8 ((N)MCdAdo), or a southern(S)-type conformation, i.e.S-type 2′-deoxy-methanocarba-adenosine 9, ((S)MCdAdo), were used as substrates for adenosine deaminase (ADA) to assess the enzyme's preference for a fixed conformation relative to the flexible conformation represented by the carbocyclic nucleoside aristeromycin (10). Further comparison between the rates of deamination of these compounds with those of the two natural substrates adenosine (Ado; 1) and 2′-deoxyadenosine (dAdo; 2), as well as with that of the conformationally locked nucleoside LNA-Ado (11), which, like the natural substrates, has a furanose O(4′) atom, helped differentiate between the roles of the O(4′) anomeric effect and sugar conformation in controlling the rates of deamination by ADA. Differences in rates of deamination as large as 10000 can be attributed to the combined effect of the O(4′) atom and the enzyme's preference for an N-type conformation. The hypothesis proposed is that ADA's preference for N-type substrates is not arbitrary; it is rather the direct consequence of the conformationally dependent O(4′) anomeric effect, which is more efficient in N-type conformers in promoting the formation of a covalent hydrate at the active site of the enzyme. The formation of a covalent hydrate at the active site of ADA precedes deamination. A new and efficient synthesis of the important carbobicyclic template 14a, a useful intermediate for the synthesis of (N)MCdAdo (8) and other conformationally restricted nucleosides, is also reported.
New Measurements of DNA Twist Elasticity

The symmetries of the DNA double helix require a new term in its linear response to stress: the coupling between twist and stretch. Recent experiments with torsionally constrained single molecules give the first direct measurement of this new material parameter. We extract its value from a recent experiment. Finally, we sketch the effect of constrained twist on entropic elasticity of DNA arising from the connection between Link, Twist, and Writhe.
Parallelization and Dynamic Load Balancing of NPARC Codes

Parallelizationanddynamicloadbalancingofthetwo-dimensionalandthree-dimensionalNPARCe owcodesare presented. Apreviously developed parallel databasepackage, GPAR, and a dynamicload balancerprogram, DLB, are used for both the two-dimensional and three-dimensional versions of NPARC. Performance characteristics of the implemented algorithms in two-dimensional and three-dimensional internal e ow cone gurations are explored. Dynamic load balancing studies are carried out with the two parallel codes for an engine inlet cone guration. The benchmark cases consist of a two-dimensional case with 4592 grid points and 2 three-dimensional cases, one with 50,950 grid points and the other with 240,000 grid points. The grids are decomposed into solution blocks and parallel computations are carried out with varying number of processors. The pressure response to unsteady perturbations of theinlet temperatureis calculated using a variable time-stepping approach specie cally developed forparallelcomputations,which takesinto accountthetime-step variationsinblockswithselectivecommunication between theblocks. Timeaccuracy ismaintainedwiththebenee tsofincreased speedup.Loadbalancing iseffective in large cases in which block computation costs are more dominant than communication costs.
Guidelines on Genetic Evaluation and Management of Lynch Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer

The Multi-Society Task Force, in collaboration with invited experts, developed guidelines to assist health care providers with the appropriate provision of genetic testing and management of patients at risk for and affected with Lynch syndrome as follows: Figure 1 provides a colorectal cancer risk assessment tool to screen individuals in the office or endoscopy setting; Figure 2 illustrates a strategy for universal screening for Lynch syndrome by tumor testing of patients diagnosed with colorectal cancer; Figures 3−6 provide algorithms for genetic evaluation of affected and at-risk family members of pedigrees with Lynch syndrome; Table 10 provides guidelines for screening at-risk and affected persons with Lynch syndrome; and Table 12 lists the guidelines for the management of patients with Lynch syndrome. A detailed explanation of Lynch syndrome and the methodology utilized to derive these guidelines, as well as an explanation of, and supporting literature for, these guidelines are provided.
Susceptibility to manipulation

All positional voting procedures can be manipulated, so it is natural to question whether some of these systems are more susceptible to being manipulated than others. In this essay, this susceptibility factor is measured for strategic action involving small groups. It is shown that the system least susceptible to micro manipulations for n = 3 candidates is the Borda Count (BC). The optimal choice changes with n, but the analysis shows that the BC always fares fairly well. On the other hand, the plurality and anti-plurality vote as well as multiple voting systems, such as approval voting and cumulative voting, always fare quite poorly with respect to susceptibility. Finally, it is shown why it is possible to justify any voting method by choosing an appropriate measure of susceptibility and imposing the appropriate assumptions on the profiles of voters. This statement emphasizes the importance of the basic assumptions of neutrality used throughout this essay.
Bone cancer pain

BACKGROUND Bone cancer pain is very common, and patients with this type of pain may be difficult to treat. Development of an experimental model for studying this condition is critical to advancing an understanding of the mechanisms that cause pain in patients with malignant disease. METHODS A murine model of bone cancer was studied. Combined analysis of the extent of tumor-induced bone destruction, pain, and neurochemical characterization of the peripheral and central nervous systems was performed to investigate bone cancer pain. Disease-induced bone destruction was assessed by radiographs and histomorphometry. Pain was assessed by spontaneous and elicited behaviors, and neurochemical analysis involved immunohistochemical detection of hyperalgesic peptides and neurochemical markers. RESULTS Mice with distal femoral sarcomas exhibited behavioral and neurochemical measures of pain. The pain condition created by malignant bone disease was distinct neurochemically from inflammatory and neuropathic pain states. Experimental evidence indicated that both disease-induced osteolysis and tumors themselves contributed to the generation of pain and that peripheral and central sensitization of the nervous system was present. CONCLUSIONS Malignant bone disease creates a unique pain state that involves sensitization of the nervous system. Major contributors to the pain state within the bone tissue are osteoclastic bone resorption and the malignant disease itself. Cancer 2003;97(3 Suppl):866–73. © 2003 American Cancer Society. DOI 10.1002/cncr.11144
Carbon dioxide and methane transport in DDR zeolite: insights from molecular simulations into carbon dioxide separations in small pore zeolites.

The silica zeolite DDR is a strong candidate for separations of CO2/CH4 because of the narrow windows that control molecular transport inside the material’s pores. We have used molecular simulations to describe diffusion of CO2 and CH4 inside DDR pores. Our simulations introduce a new force-field for this system that for the first time gives results that are consistent with experimental measurements of single-component adsorption and diffusion. Diffusivities obtained from previous simulations greatly overestimated the transport rates of CH4 and, to a lesser extent, CO2. Because CH4 diffuses extremely slowly in DDR, we applied a transition state theory-based kinetic Monte Carlo scheme to accurately describe this diffusion. The most important observation from our calculations is that the characteristics of CO2/CH4 diffusion in DDR are very different from the usual situation in nanoporous materials, where the presence of a slowly diffusing species retards transport rates of a more rapidly diffusing species. ...
Environmental Impact on the Southeast Limb of the Cygnus Loop

We analyze Chandra observations of the southeast knot of the Cygnus Loop supernova remnant. In this region, the blast wave propagates through an inhomogeneous environment. Extrinsic differences and subsequent multiple projections along the line of sight rather than intrinsic shock variations such as fluid instabilities, account for the apparent complexity of the images. Interactions between the supernova blast wave and density enhancements of a large interstellar cloud can produce the morphological and spectral characteristics. Most of the X-ray flux arises in such interactions, not in the diffuse interior of the supernova remnant. Additional observations at optical and radio wavelengths support this account of the existing interstellar medium and its role in shaping the Cygnus Loop, and they demonstrate that the southeast knot is not a small cloud that the blast wave has engulfed. These data are consistent with rapid equilibration of electron and ion temperatures behind the shock front, and the current blast wave velocity vbw ≈ 330 km s-1. Most of this area does not show strong evidence for nonequilibrium ionization conditions, which may be a consequence of the high densities of the bright emission regions.
Restoring vision through "Project Prakash": the opportunities for merging science and service.

“So how does this help society?” is a question we are often asked as scientists. The lack of immediate and tangible results cannot be held against a scientific project but statements of future promise in broad and inchoate terms can sometimes pass the benefit-buck indefinitely. There is no incentive against over-stating the benefits, especially when they are hypothetical and lie in the distant future. Few scientists will say their science is not designed to serve society. Yet the proliferation of “potential benefits” in grant proposals and the Discussion sections of research papers, in the absence of tangible translations, can make the service element of science seem like a cliched ritual. Its repetition hollows out its meaning, breeding cynicism about the idea that basic science can be of service. Expanding human knowledge can be tied intrinsically to betterment of the human condition. Our personal desire to be good Samaritans and our professional desire to be good students and researchers are not necessarily at odds. This aspiration to merge science and service can only come to fruition, however, if we actively identify opportunities that merge the two—the kind of science that necessitates service, but not at the cost of trivializing either. Here, we present Project Prakash as a prototype of what such initiatives might look like.
Electron localization studies of alkoxy polyanilines

Substituted polyanilines, namely poly(o-methoxyaniline), poly(o-ethoxyaniline), and an equimolar blend of polyaniline and poly(o-methoxyaniline) were synthesized at various oxidant/monomer molar ratios with slow and fast addition of the oxidant. Electrical conductivity, magnetic susceptibility and electron spin resonance studies are reported for these polymers doped with the following acids: hydrochloric, para-toluene sulfonic, sulfosalicylic and trifluoroacetic. Results on thin films of camphorsulfonic acid doped poly(o-methoxyaniline) and polyaniline blends with poly(o-methoxyaniline) are also reported. A systematic study of these polymers shows that the conduction is due to quasi-one-dimensional variable range hopping. A Pauli-like susceptibility is seen in all the polymers indicating the existence of ordered regions. The electron localization length is found to be much larger in poly(o-alkoxyanilines) compared with the corresponding poly(o-alkylanilines). We propose that this effect arises from the electron-donating ability of the alkoxy group in contrast to the electron-withdrawing nature of the alkyl group. We also find that samples prepared with larger amounts of the oxidant are more disordered.
Triple intersections and geometric transitions

Abstract The local neighborhood of a triple intersection of fivebranes in type IIA string theory is shown to be equivalent to type IIB string theory on a noncompact Calabi–Yau fourfold. The phases and the effective theory of the intersection are analyzed in detail.
Simulating pan-Arctic runoff with a macro-scale terrestrial water balance model

A terrestrial hydrological model, developed to simulate the high-latitude water cycle, is described, along with comparisons with observed data across the pan-Arctic drainage basin. Gridded fields of plant rooting depth, soil characteristics (texture, organic content), vegetation, and daily time series of precipitation and air temperature provide the primary inputs used to derive simulated runoff at a grid resolution of 25 km across the pan-Arctic. The pan-Arctic water balance model (P/WBM) includes a simple scheme for simulating daily changes in soil frozen and liquid water amounts, with the thaw–freeze model (TFM) driven by air temperature, modelled soil moisture content, and physiographic data. Climate time series (precipitation and air temperature) are from the National Centers for Environmental Prediction (NCEP) reanalysis project for the period 1980–2001. P/WBM-generated maximum summer active-layer thickness estimates differ from a set of observed data by an average of 12 cm at 27 sites in Alaska, with many of the differences within the variability (1σ) seen in field samples. Simulated long-term annual runoffs are in the range 100 to 400 mm year−1. The highest runoffs are found across northeastern Canada, southern Alaska, and Norway, and lower estimates are noted along the highest latitudes of the terrestrial Arctic in North America and Asia. Good agreement exists between simulated and observed long-term seasonal (winter, spring, summer–fall) runoff to the ten Arctic sea basins (r = 0·84). Model water budgets are most sensitive to changes in precipitation and air temperature, whereas less affect is noted when other model parameters are altered. Increasing daily precipitation by 25% amplifies annual runoff by 50 to 80% for the largest Arctic drainage basins. Ignoring soil ice by eliminating the TFM sub-model leads to runoffs that are 7 to 27% lower than the control run. The results of these model sensitivity experiments, along with other uncertainties in both observed validation data and model inputs, emphasize the need to develop improved spatial data sets of key geophysical quantities (particularly climate time series) to estimate terrestrial Arctic hydrological budgets better. Copyright © 2003 John Wiley & Sons, Ltd.
Analyticity and the Isgur-Wise function

Abstract We reconsider the recent derivation by de Rafael-and Taron of bounds on theslope of the Isgur-Wise function. We argue that one must be careful to include cuts starting below the heavy meson pair production threshold, arising from heavy quark-antiquark bound states, and that if such are properly accounted for then no constraints may be derived.
Kinetic controls on metalloid speciation in seawater

Abstract Mechanisms for the production of thermodynamically unstable species of three metalloids, antimony, arsenic, and selenium, and the rates of their transformation to stable forms have been critically reviewed. The occurrence of thermodynamically unstable species of these metalloids falls into two categories: reduced species in oxic waters and oxidized species in anoxic water. In surface waters biotic processes produce reduced species (e.g. Sb(III), arsenite, selenite), while in deep anoxic waters lateral advection and sinking detritus deliver oxidized species (e.g. arsenate, antimonate) from surface waters. In both cases, slow rates of conversion allow unstable species to persist. Dissolved and particulate data for antimony, arsenic, and selenium speciation in the Black Sea are used to illustrate the processes involved in this kinetic stabilization.
Molecular coding of memory.

Publisher Summary This chapter discusses the molecular coding of memory. The color discrimination experiments revealed a high degree of stimulus specificity within the same sensory modality. The most remarkable specificity has been found in maze learning in which injection of extracts of brain taken from mice trained to run a maze caused significantly faster learning but only when the recipients were tested in a maze identical With the one in which the donors were trained. It would be premature to assume absolute behavioral specificity because cross-reactions can occur even in the most exquisitely specific immune reactions. It also remains to be proven that each peptide produced in the brain corresponds to a given learned behavior. Many observations suggest that the behavior-inducing peptides are not species specific. Rat scotophobin was found to be active in mice and several species of fish, but it is probable that dark avoidance training in goldfish produces a different, perhaps related, peptide. These facts are analogous to those observed with peptide hormones. There is general agreement on memory being stored in the brain in terms of specific neuronal circuits, created by the formation of new synaptic connections at the time of learning.
GOODNESS-OF-FIT TESTS VIA PHI-DIVERGENCES

A unified family of goodness-of-fit tests based on O-divergences is introduced and studied. The new family of test statistics S n (s) includes both the supremum version of the Anderson-Darling statistic and the test statistic of Berk and Jones [Z. Wahrsch. Verw. Gebiete 47 (1979) 47-59] as special cases (s = 2 and s = 1, resp.). We also introduce integral versions of the new statistics. We show that the asymptotic null distribution theory of Berk and Jones [Z. Wahrsch. Verw. Gebiete 47 (1979) 47-59] and Wellner and Koltchinskii [High Dimensional Probability III (2003) 321-332. Birkhauser, Basel] for the Berk-Jones statistic applies to the whole family of statistics S n (s) with s ∈ [-1, 2]. On the side of power behavior, we study the test statistics under fixed alternatives and give extensions of the "Poisson boundary" phenomena noted by Berk and Jones for their statistic. We also extend the results of Donoho and Jin [Ann. Statist. 32 (2004) 962-994] by showing that all our new tests for s ∈ [- 1, 2] have the same "optimal detection boundary" for normal shift mixture alternatives as Tukey's "higher-criticism" statistic and the Berk-Jones statistic.
Spectral functions for the tomonaga-luttinger and luther-emery liquids

Abstract We calculate the finite temperature single-hole spectral function and the spin dynamic structure factor of a spinful one-dimensional Tomonaga-Luttinger liquid. Analytical expressions are obtained for a number of special cases. We also calculate the single-hole spectral function of a spin-gapped Luther -Emery liquid and obtain exact results at the free-fermion point K s = ½ These results may be applied to the analysis of angle-resolved photoemission and neutron scattering experiments on quasi-one-dimensional materials.
Surgical outcomes of robotic-assisted surgical staging for endometrial cancer are equivalent to traditional laparoscopic staging at a minimally invasive surgical center

Objective To compare peri- and post-operative complications and outcomes of robotic-assisted surgical staging with traditional laparoscopic surgical staging for women with endometrial cancer.
Consistency Conditions for Branes at Orbifold Singularities

We discuss consistency conditions for branes at orbifold singularities. The conditions have a world-sheet interpretation in terms of tadpole cancellation and a space-time interpretation in terms of anomalies. As examples, we consider type II and type I branes on C2/ZM orbifolds. We give orientifold constructions of phases of type I or heterotic string theory, involving branches with extra tensor multiplets, which arise when small SO(32) instantons sit on orbifold singularities.
Two-dimensional near-field and far-field imaging of a Ne-like Ar capillary discharge table-top soft X-ray laser

We have performed systematic measurements and numerical modeling of the divergence and exit beam size of a 46.9 nm Ne-like Ar capillary discharge pumped soft-x-ray amplifier. Two-dimensional near-field and far-field measurements were obtained over a wide range of discharge parameters. The spot size and divergence of the laser beam were observed to increase significantly with decreasing discharge pressure. Simultaneously, the beam intensity distribution changed from a single peak pattern to an annular profile. These effects are shown to be the result of increased refraction of the soft-x-ray beam, caused by larger density gradients in the plasma columns of the lower pressure discharges. The spatial images are nearly cylindrically symmetric, and have less structure than those reported in the literature for laser-driven soft-x-ray lasers. Beam profiles synthesized by model calculations are found to be in good agreement with the recorded images. The obtained images in combination with the model computations clarify the origin of the different beam patterns that are observed in capillary discharge soft-x-ray laser experiments. {copyright} {ital 1998} {ital The American Physical Society}
Synthesis, structure, and bonding of BaAuTl3 and BaAuIn3: stabilization of BaAl4-type examples of the heavier triels through gold substitution.

The title compounds have been synthesized by high temperature means and characterized by X-ray structural analysis, physical property measurements, and electronic structure calculations. The compou...
Experiments on Radiant Energy Conversion using thin Dielectric Films

Abstract Results of laboratory experiments on the conversion of radiant heat energy to electrical energy using thin dielectric films are presented. The principle involves conversion of energy from thermal to electrical utilizing the change in capacitance of a charged dielectric with temperature. Thin plastic films were selected for experiments because of their promising properties for application to solar energy converters on space vehicles. Exploratory energy conversion tests were conducted on five types of plastic films varying in thickness from 6 to 25 microns with cyclic frequencies from 0.05 to 0.7 cps at film temperatures between 20° and 100°C Power output was found to vary with the dc bias voltage and frequency as expected from theory, but an anomalous result was noted in that the variation of capacitance with temperature which appeared to be operative for energy conversion differed markedly from that which was obtained from direct capacitance measurements at various temperatures. Power output levels were very low in these tests because film leakage was higher and dielectric strengths were lower than expected from available data on the materials.
Transitional Cell Carcinoma of the Urinary Tract: Radiologic-Pathologic Correlation

The urothelium is a target tissue for carcinogens that lead to the development of transitional cell carcinomas (TCCs), both synchronous and metachronous. Although there are pathologic and imaging features common to transitional cell tumors occurring anywhere in the genitourinary tract, certain findings are more typical of tumors of the renal pelvis, ureter, or urinary bladder. A slightly irregular, fixed mass arising from any urothelial surface is characteristic of TCC. Although such masses are usually confined to the collecting system lumina, larger lesions that arise in the renal pelvis may extend into the renal parenchyma, typically in an infiltrative pattern that preserves the reniform shape. In contrast to the rapidly developing mural edema associated with obstructing calculi, the relatively slow growth of ureteral TCC allows for gradual expansion of the ureteral lumen around the tumor and is less likely to produce acute renal colic. Focal wall thickening, either eccentric or circumferential, may also be a manifestation of TCC of the ureter or, less commonly, other portions of the urinary tract. The urinary bladder is the most common site of TCC; lesions are generally confined to the lumen and typically do not extend beyond the bladder wall until quite large.
Phonon-mediated attraction between large bipolarons: Condensation to a liquid.

Self-trapped carriers of large bipolarons are redistributed among sites of their molecular orbitals in response to atomic motions. This effect lowers the phonon frequencies. The dependence of the zero-point energy on the spatial distribution of large bipolarons produces a phonon-mediated attraction between them. This dynamic quantum-mechanical effect fosters the condensation of large bipolarons into a liquid at sufficiently low temperatures.
Light by light in the muon g-2

Theoretical calculations of hadronic contributions to the muon anomalous magnetic moment are briefly reviewed. We present a model for the hadronic light-by-light scattering amplitude consistent with the short-distance constraints from the operator product expansion.
Regularity in the Local CR Embedding Problem

We consider a formally integrable, strictly pseudoconvex CR manifold M of hypersurface type, of dimension 2n−1≥7. Local CR, i.e., holomorphic, embeddings of M are known to exist from the works of Kuranishi and Akahori. We address the problem of regularity of the embedding in standard Holder spaces C a (M), a∈R. If the structure of M is of class C m , m∈Z, 4≤m≤∞, we construct a local CR embedding near each point of M. This embedding is of class C a , for every a, 0≤a<m+(1/2). Our method is based on Henkin’s local homotopy formula for the embedded case, some very precise estimates for the solution operators in it, and a substantial modification of a previous Nash–Moser argument due to the second author.
Frozen phases of random heteropolymers in disordered media.

We consider the behavior of random heteropolymers (RHP's) in random media via Monte Carlo simulations. When the bare heteropolymer prefers unlike segments to be adjacent to each other, the disordered medium induces rather unusual behavior. As temperature is scanned, we find two frozen phases with different ``folding'' patterns separated by a reentrant phase. The phenomena revealed by our results are elucidated on physical grounds, experimental tests are suggested, and the agreement between the simulation results and a simple analytical calculation is discussed.
Circuit Design of the Loaded-Line Phase Shifter

Circuit design procedures for the loaded-line phase shifter are presented, utilizing a phasor diagram representation of the line to identify its loading modes. The effects of losses in the loading elements on the circuit parameters are determined and design factors affecting bandwidth are discussed.
A Systematic Method for Kinematics Synthesis of High-Speed Mechanisms With Optimally Integrated Smart Materials

A systematic method is presented for kinematics synthesis of high-speed mechanisms with optimally integrated smart materials based actuators for the purpose of modifying the output link motion. As an example, the method is applied to a four-bar linkage mechanism that is synthesized for function generation to eliminate the high harmonic component of the output link motion. For mechanisms with rigid links, the high harmonic motions are generated due to the nonlinearity of the kinematics of their closed-loop chains. By eliminating the high harmonic component of the output motion, the potential vibrational excitation that the mechanism can impart on the overall system and its own structure is greatly reduced. The resulting system should therefore be capable of operating at higher speeds and with greater precision. A numerical example is provided together with a discussion of the application of the method to other mechanism synthesis problems and some related topics of interest.
Analytic explanation of the strong spin-dependent amplification in Hawking radiation from rotating black holes

Numerical studies of black hole greybody factors indicate that Hawking emission from a highly rotating black hole is strongly spin dependent, with particles of highest spin (gravitons) dominating the energy spectrum. So far, there has been no analytic explanation or description of this effect. Using “gravitomagnetism”, or the formal analogy between the Maxwell’s field equations for electromagnetism and Einstein’s equations for gravity, we were able to establish a link between the spin of the rotating black hole and spin of an emitted particle. Namely, the intrinsic spin of the particle creates a “mass dipole moment” which interacts with external gravitomagnetic field whose source is the rotation of the black hole. We showed that a rotating black hole prefers to shed its spin, i.e. tends to emit particles with the spin parallel to its own. We also showed that the probability for emission grows with the increasing spin of the emitted particles. The amplification factors can be huge if a black hole is highly rotating, i.e. close to extremal. When applied to central galactic black holes, the same physical mechanism indicate that particles orbiting around these black holes should have spins strongly correlated with the spin of the black hole, which may have implications for cosmic rays believed to be coming from these regions of space.
PEDESTRIAN FLOW MODELS WITH SLOWDOWN INTERACTIONS

In this paper, we introduce and study one-dimensional models for the behavior of pedestrians in a narrow street or corridor. We begin at the microscopic level by formulating a stochastic cellular automata model with explicit rules for pedestrians moving in two opposite directions. Coarse-grained mesoscopic and macroscopic analogs are derived leading to the coupled system of PDEs for the density of the pedestrian traffic. The obtained first-order system of conservation laws is only conditionally hyperbolic. We also derive higher-order nonlinear diffusive corrections resulting in a parabolic macroscopic PDE model. Numerical experiments comparing and contrasting the behavior of the microscopic stochastic model and the resulting coarse-grained PDEs for various parameter settings and initial conditions are performed. These numerical experiments demonstrate that the nonlinear diffusion is essential for reproducing the behavior of the stochastic system in the nonhyperbolic regime.
Ion and electron accelerations by large‐scale shear Alfvén waves via cross‐field instabilities

[1] Using two-dimensional particle-in-cell simulations we study the linear and nonlinear effects of a large-scale shear Alfven wave (LS-SAW) propagating parallel to the ambient magnetic field Bo. We demonstrate that ion polarization drift in the propagating SAW drives cross-field instability (CFI) by ion-electron coupling and produces electrostatic (ES) waves, which accelerate electrons parallel and ions perpendicular to Bo. Even though the large-scale SAW has no parallel electric field E∥, the E∥ of the ES wave fields embedded in LS-SAW provide a novel acceleration mechanism for the electrons moving with the group velocity of the LS-SAW. Examining data from satellite observations, we suggest that the mechanism of CFI for plasma acceleration/heating powered by LS-SAWs is distinctly possible on auroral field lines.
FIRST RESULTS FROM THE 2010 pp RUN AND PERFORMANCE OF THE CMS EXPERIMENT

In 2010, the Compact Muon Solenoid (CMS) experiment at LHC recorded over 45 pb-1 of pp collision data at $\sqrt{s} = 7~{\rm TeV}$. The large collected datasets are of very high quality and have been used to commission and calibrate the CMS detector, with the achieved performance close to the TDR specifications. CMS has re-established all the major Standard Model processes in the 2010 Run and is entering new territory in searches for New Physics, with sensitivity already exceeding that at LEP and TeVatron.
Preparation of Homoallylic Alcohols by Nickel-Catalyzed Cyclizations of Allenyl Aldehydes

The direct cyclization of allenyl aldehydes with organozincs in the presence of Ni(COD)2 provides synthetically versatile homoallylic alcohols. Both monosubstituted and 1,3-disubstituted allenes participate in the process, with the latter allowing preparation of stereochemically defined trisubstituted alkenes.
Trading networks with price-setting agents☆

Abstract In a wide range of markets, individual buyers and sellers trade through intermediaries, who determine prices via strategic considerations. Typically, not all buyers and sellers have access to the same intermediaries, and they trade at correspondingly different prices that reflect their relative amounts of power in the market. We model this phenomenon using a game in which buyers, sellers, and traders engage in trade on a graph that represents the access each buyer and seller has to the traders. We show that the resulting game always has a subgame perfect Nash equilibrium, and that all equilibria lead to an efficient allocation of goods. Finally, we analyze trader profits in terms of the graph structure — roughly, a trader can command a positive profit if and only if it has an “essential” connection in the network, thus providing a graph-theoretic basis for quantifying the amount of competition among traders.
Symmetry-protected topological phases from decorated domain walls

Symmetry-protected topological phases generalize the notion of topological insulators to strongly interacting systems of bosons or fermions. A sophisticated group cohomology approach has been used to classify bosonic symmetry-protected topological phases, which however does not transparently predict their properties. Here we provide a physical picture that leads to an intuitive understanding of a large class of symmetry-protected topological phases in d=1,2,3 dimensions. Such a picture allows us to construct explicit models for the symmetry-protected topological phases, write down ground state wave function and discover topological properties of symmetry defects both in the bulk and on the edge of the system. We consider symmetries that include a Z2 subgroup, which allows us to define domain walls. While the usual disordered phase is obtained by proliferating domain walls, we show that symmetry-protected topological phases are realized when these domain walls are decorated, that is, are themselves symmetry-protected topological phases in one lower dimension. This construction works both for unitary Z2 and anti-unitary time reversal symmetry.
Iron trichloride promoted hydrolysis of potassium organotrifluoroborates

In the presence of iron trichloride, the hydrolysis of potassium organotrifluoroborates occurs smoothly at room temperature to afford the corresponding organoboronic acids in good to excellent yields. The hydrolysis is effective for aryltrifluoroborates as well as alkenyl- and alkyl-trifluoroborates.
Olefin metathesis involving ruthenium enoic carbene complexes.

Olefin metathesis has become a valuable reaction in organic synthesis, as has been demonstrated by its frequent use as the key bond constructions for total syntheses of many natural products. With the recent discovery of highly active catalyst 1, trisubstituted and functionalized alkenes have been synthesized efficiently by cross-metathesis (CM), further expanding the substrate scope for this reaction. With these successes in hand, unprecedented metathesis reactions were explored. There have been no previous reports of the dimerization of α,β-unsaturated carbonyl compounds by a metathesis mechanism. Molybdenum- and tungsten-based catalysts form metallocyclobutane with acrylates, but they are inactive due to carbonyl oxygen chelation. Our group reported the synthesis of ester carbene 4 by a nonmetathesis route and showed that 4 was extremely reactive. In fact, ester carbene 4 was the first carbene to ring-open cyclohexene but did not react in a catalytic fashion.4 The nontrivial synthesis, lack of stability, and the ineffective catalytic activity of ester carbene 4 has limited its uses in organic synthesis.
The modern FPGA as discriminator, TDC and ADC

Recent generations of Field Programmable Gate Arrays (FPGAs) have become indispensable tools for complex state machine control and signal processing, and now routinely incorporate CPU cores to allow execution of user software code. At the same time, their exceptional performance permits low-power implementation of functionality previously the exclusive domain of dedicated analog electronics. Specific examples presented here use FPGAs as discriminator, time-to-digital (TDC) and analog-to-digital converter (ADC). All three cases are examples of instrumentation for current or future astroparticle experiments.
The scope test revisited

Sensitivity to scope has become an acid test for the validity of responses to non-market valuation scenarios. The theoretical relationship between whether a subject's responses exhibit sensitivity to scope and whether consistent preferences underlie those responses is examined. It is found that sensitivity to scope is neither necessary nor sufficient for preference consistency. Moreover, while continuous, strongly monotonic and total preferences yield scope, the converse fails to hold. The results suggest caution in scope's application as a survey validation tool.
A Simple Family of Models for Eccentric Keplerian Fluid Disks

To be in a long-lived configuration, the density in a fluid disk should be constant along streamlines to prevent compressional (PdV) work from being done cyclically around every orbit. In a pure Kepler potential, flow along aligned elliptical streamlines of constant eccentricity will satisfy this condition. For most density profiles, differential precession driven by the pressure gradient will destroy the alignment; however, in the razor-thin approximation there is a family of simple equilibria in which the precession frequency is the same at all radii. These disks may therefore be long-lived at significant eccentricities. The density can be made axisymmetric as r → 0 while maintaining the precession rate by relaxing the requirement of constancy along streamlines in an arbitrarily small transition region near the center. In the limit of small eccentricity, the models can be seen as acoustically perturbed axisymmetric disks, and the precession rate is shown to agree with linear theory. The perturbation is a traveling wave similar to an ocean wave, with the fluid rising and falling epicyclically in the gravitational field of the central mass. The expected emission-line profiles from the eccentric disks are shown to be strongly asymmetric in general and, in extreme cases, prone to misinterpretation as single narrow lines with significant velocity offsets.
An efficient synthesis of substituted prolines by the selective reduction and reductive cyanation of 2-pyrrolidones

Abstract Substituted pyrrolidones undergo selective reduction using Cp2ZrHCl (Schwartz's reagent) to form Δ1-pyrrolines, which can be isolated or directly cyanated and hydrolyzed to the corresponding proline. Short syntheses of glutamic semialdehyde (ethyl ester), the marine metabolite (2S,5S)-pyrrolidine-2,5-dicarboxylic acid, and the conformationally constrained amino acid 5,5-dimethylproline, are reported.
Dust Streamers in the Virgo Galaxy M86 from Ram Pressure Stripping of Its Companion VCC 882

The giant elliptical galaxy M86 in Virgo has a ~28 kpc long dust trail inside its optical halo that points toward the nucleated dwarf elliptical galaxy VCC 882. The trail seems to be stripped material from the dwarf. Extinction measurements suggest that the ratio of the total gas mass in the trail to the blue luminosity of the dwarf is about unity, which is comparable to such ratios in dwarf irregular galaxies. The ram pressure experienced by the dwarf galaxy in the hot gaseous halo of M86 was comparable to the internal gravitational binding energy density of the presumed former gas disk in VCC 882. Published numerical models of this case are consistent with the overall trail-like morphology observed here. Three concentrations in the trail may be evidence for the predicted periodicity of the mass loss. The evaporation time of the trail is comparable to its age obtained from the relative speed of the galaxies and the trail length. Thus the trail could be continuously formed from stripped replenished gas if the VCC 882 orbit is bound. However, the high gas mass and the low expected replenishment rate suggest that this is only the first stripping event. Implications for the origin of nucleated dwarf ellipticals are briefly discussed.
Laser Ranging for Gravitational, Lunar and Planetary Science

More precise lunar and Martian ranging will enable unprecedented tests of Einstein's theory of general relativity as well as lunar and planetary science. NASA is currently planning several missions to return to the Moon, and it is natural to consider if precision laser ranging instruments should be included. New advanced retroreflector arrays at carefully chosen landing sites would have an immediate positive impact on lunar and gravitational studies. Laser transponders are currently being developed that may offer an advantage over passive ranging, and could be adapted for use on Mars and other distant objects. Precision ranging capability can also be combined with optical communications for an extremely versatile instrument. In this paper we discuss the science that can be gained by improved lunar and Martian ranging along with several technologies that can be used for this purpose.
Enantiodivergent hydroboration reactions of a racemic allenylsilane with diisopinocampheylborane and Curtin–Hammett controlled double asymmetric crotylboration reactions of (S)-E-α-phenyldimethylsilyl(ddiisopinocampheyl)-crotylborane

The enantiodivergent hydroboration reactions of racemic allenylsilane (±)-4 with (dIpc)2BH and subsequent crotylboration of achiral aldehydes with the product crotylborane (S)-E-5 at −78 °C provide (E)-δ-silyl-anti-homoallylic alcohols 6 in 71–89% yield and with 93–96% ee. Intriguingly, mismatched double asymmetric crotylboration reactions of enantioenriched chiral aldehydes 20 with (S)-E-5 proceed under Curtin–Hammett control to give anti-β-hydroxylcrotylsilanes 24 as the only products.
Independent Directors and the Propensity to Pay Dividends

Abstract Using data from 944 public companies in 2006, I examine how a firm's propensity to pay dividends is related to (i) board independence and (ii) independent directors' tenure, number of board seats (busy) and equity incentive compensation. After controlling for the effects of traditional economic, CEO entrenchment and ownership determinants of the propensity to pay dividends, I find evidence of a positive association between the propensity to pay and (i) board independence and (ii) director tenure, and a negative association between the propensity to pay and (i) busy directors and (ii) greater equity incentive compensation in the director pay structure. I find consistent results when the decision is to pay cash dividends or repurchase shares. In further tests, I find that equity incentive compensation in the independent director pay structure is the most pervasive determinant across other dividend measures such as dividend payout, total payout and repurchases. Overall, the findings suggest that the characteristics of independent directors are important determinants of the payout policy. The results also suggest that future corporate governance research could benefit from incorporating characteristics of independent directors rather than limiting governance measures to board independence especially when recent empirical evidence (Linck et al., 2008, 2009) shows convergence, and therefore, narrowing variation in the proportion of outsiders and insiders on a board.
Copper-Catalyzed Enantioselective Intramolecular Alkene Amination/Intermolecular Heck-Type Coupling Cascade

Enantioselective copper-catalyzed cyclization of γ-alkenylsulfonamides and a δ-alkenylsulfonamide in the presence of a range of vinyl arenes results in variously functionalized 2-substituted chiral nitrogen heterocycles via a formal alkene C–H functionalization process. Application of this reaction to the concise synthesis of a 5-HT7 receptor antagonist is demonstrated.