cssi/SciSciGPT-SciSciNet huggingface dataset:
Local existence for the one‐dimensional Vlasov–Poisson system with infinite mass

A collisionless plasma is modelled by the Vlasov–Poisson system in one dimension. We consider the situation in which mobile negative ions balance a fixed background of positive charge, which is independent of space and time, as ∣x∣ ∞. Thus, the total positive charge and the total negative charge are both infinite. Smooth solutions with appropriate asymptotic behaviour are shown to exist locally in time, and criteria for the continuation of these solutions are established. Copyright © 2006 John Wiley & Sons, Ltd.
Scattering and radiative properties of complex soot and soot-containing aggregate particles

Abstract We use the superposition T-matrix method to compute the scattering matrix elements and optical cross-sections for a variety of complex soot and soot-containing aggregate particles in random orientation at a visible wavelength 0.628 μm. It is shown that random variations in the geometrical configuration of monomers in a soot cluster for fixed fractal dimension and prefactor, monomer size, and number of monomers have a rather weak effect on scattering and absorption, at least in the visible part of the spectrum. Thus, the electromagnetic scattering and absorption characteristics of a single cluster realization are sufficient to represent the mean values obtained by averaging over many realizations of the “equivalent” clusters generated for the same fractal parameters. However, the results for the soot clusters differ fundamentally from those calculated for the volume-equivalent soot sphere and for the corresponding external mixture of soot monomers, assuming that there are no electromagnetic interactions between the monomers. We also compute and analyze the scattering and absorption properties of aerosols formed by semi-external aggregation of larger ammonium sulfate, silica, or dust particles with soot clusters as well as semi-external aggregates consisting of several components with different sizes and refractive indices. Depending on its chemical composition and size, the larger particle that is in touch with a soot cluster can strongly influence, or even dominate, the overall optical characteristics of the aggregate. Aggregation can result in stronger extinction, absorption, and scattering cross-sections relative to those computed for the corresponding external mixture. Possibly owing to mutual shadowing, the optical cross-sections of multi-component aggregates are smaller than those of their externally mixed counterparts, but by no more than ∼20%. Implications of our study for analyses of remote sensing observations and atmospheric radiation balance computations are discussed.
Equation for optimal power-limited spacecraft trajectories

References Lupash, L. O., "A New Algorithm for Computation of the Geodetic Coordinates as a Function of Earth-Centered Earth-Fixed Coordinates," Journal of Guidance, Control, and Dynamics, Vol. 8, No. 6, 1985, pp. 787-789. Nautiyal, A., "Algorithm to Generate Geodetic Coordinates from Earth-Centered Earth-Fixed Coordinates," Journal of Guidance, Control, and Dynamics, Vol. 11, No. 3, 1988, pp. 281-283. Olson, D. K., "Calculation of Geodetic Coordinates from EarthCentered Earth-Fixed Coordinates," Journal of Guidance, Control, and Dynamics, Vol. 11, No. 2, 1988, pp. 188-190. Levin, J. zev, "A Rational Parametric Approach to Latitude, Longitude, and Altitude," Navigation: Journal of The Institute of Navigation, Vol. 35, No. 3, 1988, pp. 361-370. 5 Jones, B. W., An Introduction to Modern Algebra, Macmillan, New York, 1975, pp. 301-311. The limit on power available to the engine from a separate power source is usually prescribed as an upper bound on the exhaust power:
Numerical experiments for nonlinear filters with exact particle flow induced by log-homotopy

We show numerical experiments on a new theory of exact particle flow for nonlinear filters. This generalizes our theory of particle flow that was already many orders of magnitude faster than standard particle filters and which is several orders of magnitude more accurate than the extended Kalman filter for difficult nonlinear problems. The new theory generalizes our recent log-homotopy particle flow filters in three ways: (1) the particle flow corresponds to the exact flow of the conditional probability density; (2) roughly speaking, the old theory was based on incompressible flow (like subsonic flight in air), whereas the new theory allows compressible flow (like supersonic flight in air); (3) the old theory suffers from obstruction of particle flow as well as singularities in the equations for flow, whereas the new theory has no obstructions and no singularities. Moreover, our basic filter theory is a radical departure from all other particle filters in three ways: (a) we do not use any proposal density; (b) we never resample; and (c) we compute Bayes' rule by particle flow rather than as a point wise multiplication.
Computers, Traditional Scholarship, and the ACLS

Through its program of fellowships and grants-in-aid since 1964, the American Council of Learned Societies has been encouraging humanities and social science scholars to take an interest in the application of computers to their work. The IBM Corporation has generously funded this ACLS program. To date assistance has been provided to twenty-five scholars from the fields of history, political science, anthropology, musicology, language, literature, classics, and linguistics. From such involvement the feeling has grown that far more needs to be done to assist computer-oriented researchers in the humanities. But there has developed as well the view that much could also be done for the scholar who is not now or apt to be computer-oriented. Computerized bibliographical control of literature in the humanities and social sciences looms large and promising as a field. To set the machines to the task of bibliographical control not only will evoke further interest in computer applications within the various disciplines but, equally important, will also provide scholars with services and tools now unavailable to them. In some ways this might even permit the scholar to view the computer as an aid to research rather than necessarily dictating the course that his research should take. More can be expected from this approach than from the one that has generally been taken, of flogging the humanist for his failure to be interested in computers. A number of converging factors tend to accelerate developments in this direction. Information retrieval systems developed for the sciences and engineering, for medicine, and for the Department of Defense have provided the necessary hardware and software, at least to the point where significant work can now be undertaken. There are now as well a number of humanists and social scientists who have computer experience and competence to assist in programming and systems design. The newer disciplines of information and communications are emerging with great vigor and promise. Moreover, it would appear that computer scientists are beginning to regard the humanities as a new frontier which offers considerable challenge. What is lacking at the moment is a mechanism to make known and available to scholars and their professional organizations the computer capabilities for bibliographical control. The need for such a mechanism is urgent. For standing in the wings and looking on at developments in information retrieval are the ever-growing legions of scholars and a host of eager graduate students. To experiment with the development of just such a human mechanism, the ACLS Bibliographic Data Processing Center project has emerged. Working now in conjunction with New York University's Institute for Computer Research in the Humanities, the ACLS is exploring ways in which needed bibliographical information can be channeled to scholars in the various disciplines of the humanities and social sciences. Funding for
Analysis of pollutant formation and control and fuel economy in diesel engines

Publisher Summary This chapter presents a comparison between the characteristics of the diesel and other automobile engines. The high thermal efficiency of the diesel engine is mainly caused by the relatively high compression ratio required to start the autoignition process, the lower pumping losses as a result of the absence of the throttle valve, and the overall lean mixture required to achieve an efficient heterogeneous combustion process. The chapter describes high speed diesel engines used for automotive applications. Pollutants from the automotive power plants are found to be a major contributor of the photochemical smog formation in the atmosphere and a cause of social and health problems. The preignition processes in diesel engines may be divided into physical and chemical processes. The physical processes include spray disintegration and droplet formation; heating of the liquid fuel and evaporation; and diffusion of the vapor into the air to form a combustible mixture. The chemical processes include the decomposition of the heavy hydrocarbons into lighter components and the preignition chemical reactions between the decomposed components and oxygen.
How responsive is Chinese export supply to market signals

Abstract This paper studies the behavior of Chinese exporters from the mid-1980s through 2001. Extensive quarterly data on values and quantities of major export products have been taken from Chinese customs statistics to form a panel data set and aggregate export unit price and volume indices. The data are used to estimate export supply price elasticities, including by industry groups. The overall results indicate an increase in the responsiveness of export supply to market price signals in more recent periods following reforms.
Prediction of Erosion Due to Solid Particle Impact in Single-Phase and Multiphase Flows

Solid particle erosion of metal surfaces is a major problem in several fluid handling industries due to unpredicted equipment failure and production loss. The prediction of erosion is difficult even in a single-phase flow. The complexity of the problem increases significantly in a multiphase flow due to the existence of different flow patterns where the spatial distribution of the phases changes with the change of phase flow rates. Earlier predictive means of erosion in single and multiphase flows were primarily based on empirical data and were limited to the flow conditions of the experiments. A mechanistic model has been developed for predicting erosion in single-phase and multiphase flows considering the effects of solid particle impact velocities that cause erosion. Local fluid velocities and simplified equations are used to calculate erosion rates assuming a uniform distribution of solid particles in the liquid phase in the multiphase flow. Another assumption was that the solid particle velocities are similar to the velocity of the fluids surrounding the particles. As the model is based on the physics of multiphase flow and erosion phenomenon, it is more general than the previous models. The predicted erosion rates obtained by the mechanistic model are compared to experimental data available in the literature showing a reasonably good agreement.
Discovery of sn 2009nz associated with grb 091127

We report SMARTS, Gemini, and Swift-UVOT observations of the optical transient (OT) associated with gamma-ray burst (GRB) 091127, at redshift 0.49, taken between 0.9 hr and 102 days following the Swift trigger. In our early-time observations, the OT fades in a manner consistent with previously observed GRB afterglows. However, after nine days post-burst, the OT is observed to brighten for a period of ∼two weeks, after which the source resumes fading. A comparison of this late-time "bump" to SN 1998bw (the broad-lined Type Ic supernova associated with GRB 980425), and several other GRB supernovae (SNe), indicates that the most straightforward explanation is that GRB 091127 was accompanied by a contemporaneous SN (SN 2009nz) that peaked at a magnitude of MV = -19.0 ± 0.2. SN 2009nz is globally similar to other GRB SNe, but evolves slightly faster than SN 1998bw and reaches a slightly dimmer peak magnitude.We also analyze the early-time UV-optical-IR spectral energy distribution of the afterglow of GRB 091127 and find that there is little to no reddening in the host galaxy along the line of sight to this burst. © 2010 The American Astronomical Society.
“Greener” chemical syntheses using mechanochemical mixing or microwave and ultrasound irradiation

Abstract Various emerging “greener” strategic pathways, researched primarily in the author's own laboratory, are summarized. They include solvent-free mechanochemical methods that involve the use of hypervalent iodine reagents at room temperature for the synthesis of heterocyclic entities, and useful conversion of ketones into β-keto sulfones and their α-tosyloxy derivatives in high yields. A solvent-free approach that involves microwave (MW) exposure of neat reactants (undiluted) catalyzed by the surfaces of less-expensive and recyclable mineral supports, such as alumina, silica, clay, or “doped” surfaces, is described; it is applicable to a wide range of cleavage, condensation, cyclization, rearrangement, oxidation, and reduction reactions, including rapid one-pot assembly of heterocyclic compounds from in situ generated reactive intermediates. The strategy is adaptable to multi-component reactions, e.g. Ugi and Biginelli reactions, for rapid assembly of a library of compounds. Synthesis of a wide varie...
Cooperative N-heterocyclic carbene/Lewis acid catalysis for highly stereoselective annulation reactions with homoenolates.

A new approach that takes advantage of N-heterocyclic carbene/Lewis acid cooperative catalysis provides access to cis-1,3,4-trisubstituted cyclopentenes from enals and chalcone derivatives with high levels of diastereoselectivity and enantioselectivity. The presence of Ti(OiPr)4 as the Lewis acid allows for efficient substrate preorganization, which translates into high levels of diastereoselectivity. Additionally, we demonstrate the possibility of controlling the absolute stereochemistry of NHC-catalyzed reactions by employing a catalytic amount of a chiral Lewis acid as the unique source of optically active promoter.
Synthesis and anticonvulsant activities of N-Benzyl-2-acetamidopropionamide derivatives.

Studies have demonstrated that 2-substituted N-benzyl-2-acetamidoacetamides (2) are potent anticonvulsants. A recent investigation has led to the hypothesis that an important structural feature in 2 for maximal anticonvulsant activity is the placement of a small, substituted heteroatom moiety one atom from the C(2) site. This paper validates this hypothesis. Twelve derivatives of N-benzyl-2-acetamidopropionamide have been prepared in which six different heteroatom substituents (chloro, bromo, iodo, oxygen, nitrogen, and sulfur) were incorporated at the C(3) site. Highly potent activities were observed for the two oxygen-substituted derivatives, N-benzyl-2-acetamido-3-methoxypropionamide (18) and N-benzyl-2-acetamido-3-ethoxypropionamide (19). The ED50 values in mice following intraperitoneal (i.p.) dosing for the maximal electroshock-induced seizure test for 18 and 19 were 8.3 and 17.3 mg/kg, respectively. These values compared favorably to the ED50 value found for phenytoin (ED50 = 6.5 mg/kg). Comparable activities were observed for 18 and 19 upon oral (p.o.) administration to rats (18, ED50 = 3.9 mg/kg; 19, ED50 = 19 mg/kg; phenytoin, ED50 = 23 mg/kg). Evaluation of the individual stereoisomers for 18 demonstrated that the principal anticonvulsant activity resided in the (R)-stereoisomer. The ED50 value for (R)-18 was 4.5 mg/kg, and the ED50 for (S)-18 exceeded 100 mg/kg. This difference in activity for the two stereochemical isomers surpassed comparable values for other members within this class of compounds. The protective indices (PI = TD50/ED50) (where TD50 represents a neurotoxic dose impairing rotorod performance) for (R)-18 in mice (i.p.) and in rats (p.o.) were 6.0 and > 130, respectively.
A generalization of the alcove model and its applications

The alcove model of the first author and Postnikov uniformly describes highest weight crystals of semisimple Lie algebras. We construct a generalization, called the quantum alcove model. In joint work of the first author with Naito, Sagaki, Schilling, and Shimozono, this was shown to uniformly describe tensor products of column shape Kirillov---Reshetikhin crystals in all untwisted affine types; moreover, an efficient formula for the corresponding energy function is available. In the second part of this paper, we specialize the quantum alcove model to types $$A$$A and $$C$$C. We give explicit affine crystal isomorphisms from the specialized quantum alcove model to the corresponding tensor products of column shape Kirillov---Reshetikhin crystals, which are realized in terms of Kashiwara---Nakashima columns.
Diffractive production at collider energies and factorization

Abstract One of the more interesting developments from recent collider experiments is the finding that hadronic total cross sections as well as elastic cross sections can be described by the exchange of a “soft Pomeron” pole in the near-forward limit. The most important consequence of Pomeron being a pole is the factorization property. However, due to Pomeron intercept being greater than 1, the extrapolated single-diffraction dissociation cross section based on a classical triple-Pomeron formula is too large leading to a potential unitarity violation at Tevatron energies, which has been referred to as “Dino's paradox”. We review the resolution which involves a proper implementation of final-state screening correction, with “flavoring” for Pomeron as the primary dynamical mechanism for setting the relevant energy scale. In this approach, factorization remains intact, and unambiguous predictions for double-Pomeron exchange, doubly diffraction dissociation, etc., both at Tevatron and at LHC energies, can be made.
Towards better combustion of lunar regolith with magnesium

Abstract It has been shown recently that lunar regolith forms combustible, thermite-type mixtures with magnesium. Combustion of these mixtures could be used for the production of construction materials on the Moon. The present paper focuses on decreasing magnesium content in mixtures based on JSC-1A lunar regolith simulant and increasing the density and strength of the combustion products of these mixtures. Combustion of JSC-1A/Mg mixture pellets was studied in argon gas and in silica powder. Preheating to 100 °C decreased the minimum concentration of magnesium, required for combustion, from 10 wt.% to 8 wt.%. Submerging the pellets into silica increased the product strength. SHS compaction experiments were conducted, which involved quasi-isostatic pressing of the products immediately after the end of the combustion process. This resulted in a significant increase in the product density. The compressive strength exceeded 10 MPa, i.e., was higher than that of common bricks (5 MPa).
Optimizing noncontiguous accesses in MPI – IO

The I/O access patterns of many parallel applications consist of accesses to a large number of small, noncontiguous pieces of data. If an application's I/O needs are met by making many small, distinct I/O requests, however, the I/O performance degrades drastically. To avoid this problem, MPI-IO allows users to access noncontiguous data with a single I/O function call, unlike in Unix I/O. In this paper, we explain how critical this feature of MPI-IO is for high performance and how it enables implementations to perform optimizations. We first provide a classification of the different ways of expressing an application's I/O needs in MPI-IO -- we classify them into four levels, called levels 0--3. We demonstrate that, for applications with noncontiguous access patterns, the I/O performance improves dramatically if users write their applications to make level-3 requests (noncontiguous, collective) rather than level-0 requests (Unix style). We then describe how our MPI-IO implementation, ROMIO, delivers high performance for noncontiguous requests. We explain in detail the two key optimizations ROMIO performs: data sieving for noncontiguous requests from one process and collective I/O for noncontiguous requests from multiple processes. We describe how we have implemented these optimizations portably on multiple machines and file systems, controlledmore » their memory requirements, and also achieved high performance. We demonstrate the performance and portability with performance results for three applications -- an astrophysics-application template (DIST3D), the NAS BTIO benchmark, and an unstructured code (UNSTRUC) -- on five different parallel machines: HP Exemplar, IBM SP, Intel Paragon, NEC SX-4, and SGI Origin2000.« less
High performance team interaction in an air medical program.

Abstract Introduction: The purpose of this qualitative study was to identify and describe the elements of a high performance team interaction on an air medical transport mission. Methods: The phenomenologic method as described by Giorgi was used to guide data collection and analysis. Six flight nurses from around the United States were interviewed and audiotaped as they described their subjective perception of a high performance team experience. Results: Four themes emerged from the data: collaboration, mutual respect and trust, fitness standards, and synergy. Conclusion: Implications for flight crews involved in this high performance environment may require attention to the identified themes to promote team performance.
Prediction of Elastic-Airplane Lateral Dynamics from Rigid-Body Aerodynamics

Control-configured vehicle technology has increased the demand for detailed analysis of dynamic stability and control, handling and ride qualities, and control system dynamics at the early stages of preliminary design and development. For these early analyses an approximate, but reasonably accurate, set of equations of motion for elastic airplanes is needed. Such a formulation is developed for the lateral dynamics of elastic airplanes. It makes use of rigid-body aerodynamic stability derivatives and the antisymmetric elastic mode shapes and frequencies in formulating the forces and moments due to elastic motion. Verification of accuracy was made by comparison with B-1 airplane dynamics obtained by other methods. Frequencies and damping ratios of the coupled modes agree acceptably well with four antisymmetric elastic modes included.
Monopole operators in three-dimensional N = 4 SYM and mirror symmetry

We study non-abelian monopole operators in the infrared limit of three-dimensional SU(N-c) and N = 4 SU(2) gauge theories. Using large N-f expansion and operator-state isomorphism of the resulting superconformal field theories, we construct monopole operators which are (anti-)chiral primaries and compute their charges under the global symmetries. Predictions of three-dimensional mirror symmetry for the quantum numbers of these monopole operators are verified.
Optical Design for a Spatial-Spectral Volume Holographic Imaging System

Spatial Spectral Holographic imaging system (S2-VHIS) is a promising alternative to confocal microscopy due to its capabilities to simultaneously image several sample depths with high resolution. However, the field of view of previously presented S2-VHIS prototypes has been restricted to less than 200μm. This paper presents experimental results of an improved S2-VHIS design which have a field of view of ~1mm while maintaining high resolution and dynamic range.
A method to extract potentials from the temperature dependence of Langmuir constants for clathrate-hydrates

It is shown that the temperature dependence of Langmuir constants contains all the information needed to determine spherically averaged intermolecular potentials. An analytical “inversion” method based on the standard statistical model of van der Waals and Platteeuw is presented which extracts cell potentials directly from experimental data. The method is applied to ethane and cyclopropane clathrate-hydrates, and the resulting potentials are much simpler and more meaningful than those obtained by the usual method of numerical fitting with Kihara potentials.
Diffeomorphism-Invariant Spin Network States☆

Abstract We extend the theory of diffeomorphism-invariant spin network states from the real-analytic category to the smooth category. Suppose that G is a compact connected semisimple Lie group and P → M is a smooth principal G -bundle. A “cylinder function” on the space of smooth connections on P is a continuous complex function of the holonomies along finitely many piecewise smoothly immersed curves in M . We construct diffeomorphism-invariant functionals on the space of cylinder functions from “spin networks”: graphs in M with edges labeled by representations of G and vertices labeled by intertwining operators. Using the “group averaging” technique of Ashtekar, Marolf, Mourao, and Thiemann, we equip the space spanned by these diffeomorphism-invariant spin network states with a natural inner product.
Preparation of 5-formyl- and 5-acetylbarbituric acids, including the corresponding Schiff bases and phenylhydrazones

Abstract Simple, effective, and high yield synthetic procedures for formylation and acetylation of barbituric acid derivatives is described. Generated 5-acylbarbituric acids are transformed into the corresponding Schiff bases in high yield condensation reactions with ω-aminoalkanoic acids and nitrophenylhydrazines.
Religion and Political Economy in an International Panel

Two important theories of religiosity are the secularization hypothesis and the religion-market model. According to the former, sometimes called a demand-side theory, economic development reduces religious participation and beliefs. According to the latter, described as a supply-side theory, religiosity depends on the presence of a state religion, regulation of the religion market, suppression of organized religion under Communism, and the degree of religious pluralism. We assess the theories by using survey information for 68 countries over the last 20 years, measuring attendance at formal religious services, religious beliefs, and self-identification as religious. In accordance with the secularization view, overall economic development-represented by per capita GDP-tends to reduce religiosity. Moreover, instrumental estimates suggest that this link reflects causation from economic development to religiosity, rather than the reverse. The presence of an official state religion tends to increase religiosity, probably because of the subsidies that flow to organized religion. However, in accordance with the religion-market model, religiosity falls with government regulation of the religion market and Communist suppression. Greater religious pluralism raises attendance at formal services but has no significant effects on religious beliefs or self-identification as religious. Although religiosity declines overall with economic development, the nature of the interaction varies with the dimension of development. For example, religiosity is positively related to education and the presence of children and negatively related to urbanization.
Geodesic deviation in Regge calculus

Geodesic deviation is the most basic manifestation of the influence of gravitational fields on matter. We investigate geodesic deviation within the framework of Regge calculus, and compare the results with the continuous formulation of general relativity on two different levels. We show that the continuum and simplicial descriptions coincide when the cumulative effect of the Regge contributions over an infinitesimal element of area is considered. This comparison provides a quantitative relation between the curvature of the continuous description and the deficit angles of Regge calculus. The results presented might also be of help in developing generic ways of including matter terms in the Regge equations.
Competition Between Fatigue Crack Propagation and Wear

Based on a semi-empirical derivation of the Paris fatigue law, the fatigue crack length a is related to the yield limit or flow stress, which ultimately is related to the hardness of the material. The analysis considers together the cyclic loading, which tends to increase the surface crack length, and the wear, which tends to decrease the crack length at the surface, and shows that under certain conditions a stable crack length may be developed. Experiments conducted on two test groups ((i) Rc = 58.5 and (ii) Rc = 62.7) tend to support the present analysis.
Perspectives on the first principles elucidation and the design of active sites

First principle quantum chemical methods and atomistic simulations are used to probe active sites, ensembles, and reaction environments and assist in their design for metal catalyzed reactions. Heterogeneous catalytic reactions which take place over one- or two-metal-atom centers such as hydrogenation and dehydrogenation resemble analogous homogeneous systems and tend to be structure insensitive. Alloys can be used in order to improve the selectivity of these reactions to specific products by shutting down unwanted paths that lead to byproduct formation. The activity for these reactions, however, does not change appreciably with changes in structure or surface composition. For hydrogenation, this is due to a balance between lower hydrogen surface coverages which decrease the rate and more weakly bound hydrocarbon intermediates which increase the rate. Reactions that require larger ensemble sizes such as N2 activation, ethane hydrogenolysis, hydrocarbon coupling, and vinyl acetate synthesis are much more structure sensitive. Both the activity and the selectivity can be improved in these systems by the optimal design of the specific sites and bifunctional ensembles. An ab initio based kinetic Monte Carlo simulation scheme was developed and used to engineer Pd/Au alloys in order to improve the activity for vinyl acetate synthesis by about a factor of 2 and the selectivity by about 5%. Altering the properties of the solution phase offers a means to probe and manipulate part of the 3D atomic structure around the active sites. More specifically we examine the activation of water over Pt, PtRu, and Ru surfaces in the presence as well as the absence of solution. Our results show that Pt, Ru, and the water solution work together synergistically to provide a low energy heterolytic path for the activation of water to form OH∗(−), H5O2+(aq), and 1e-. Ab initio MD simulations were subsequently used and uncovered a new path for the diffusion of hydroxyl across the surface which involves a sequence of proton transfer reactions.
Higher-power free-electron lasers

Abstract The dominant process is spontaneous emission, enhanced by prebunching on a length scale short compared with the wavelength, and sustained by a strong axial electric field. Generally speaking, the potential for very high power levels is achieved at the expense of phase coherence relative to the conventional free-electron laser.
A new way to measure cirrus cloud ice water content by using ice Raman scatter with Raman lidar

High and cold cirrus clouds mainly contain irregular ice crystals, such as, columns, hexagonal plates, bullet rosettes, and dendrites, and have different impacts on the climate system than low-level clouds, such as stratus, stratocumulus, and cumulus. The radiative effects of cirrus clouds on the current and future climate depend strongly on cirrus cloud microphysical properties including ice water content (IWC) and ice crystal sizes, which are mostly an unknown aspect of cinus clouds. Because of the natural complexity of cirrus clouds and their high locations, it is a challenging task to get them accurately by both remote sensing and in situ sampling. This study presents a new method to remotely sense cirrus microphysical properties by using ice Raman scatter with a Raman lidar. The intensity of Raman scattering is fundamentally proportional to the number of molecules involved. Therefore, ice Raman scattering signal provides a more direct way to measure IWC than other remote sensing methods. Case studies show that this method has the potential to provide essential information of cirrus microphysical properties to study cloud physical processes in cirrus clouds.
Highly Efficient Diastereoselective Reduction of α-Fluoroimines

A highly selective reduction of α-fluoroimines to the corresponding β-fluoroamines has been developed utilizing trichlorosilane as the reductant. The key aspect of this reaction is the ability of fluorine and nitrogen to activate organosilanes leading to high diastereoselectivity (>100:1) in the product distribution. This new method provides a new avenue for the diastereoselective synthesis of β-fluorinated amines in good yields and selectivity.
A biomimetic chemical synthesis of humulene from farnesol

Abstract The first synthesis of humulene ( 1 ) by a biomimetic cation-olefin cyclization route is reported.
A Near-Solar Metallicity, Nitrogen-deficient Lyman Limit Absorber Associated with Two S0 Galaxies*

The UV spectrum of the bright quasar PHL 1811 at zem = 0.192 reveals a foreground gas system at z = 0.080923 with log N(H ) = 17.98 ? 0.05. We have determined the abundances of various atomic species in this system from a spectrum covering the wavelength range 1160-1730 ? recorded at 7 km s-1 resolution by the E140M grating of the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST), supplemented by coverage at shorter wavelengths by the Far Ultraviolet Spectroscopic Explorer (FUSE). The abundances of C II, Si II, S II, and Fe II compared to that of O I indicate that a considerable fraction of the gas is in locations where the hydrogen is ionized. An oxygen abundance [O/H] = -0.19 ? 0.08 in the H I-bearing gas indicates that the chemical enrichment of the gas is unusually high for an extragalactic QSO absorption system. However, this same material has an unusually low abundance of nitrogen, [N/O] 10-3 cm-3 by modeling the ionization by the intergalactic radiation field and an upper bound n(e) < 0.07 cm-3 from the absence of much C II in an excited fine-structure level. The thermal pressure in the range 4 cm-3 K < p/k < 140 cm-3 K could be confined by a warm-hot intergalactic medium (WHIM) structure with ?/ ~ 20 that might accompany a wall of galaxies at the same redshift, seen in data from the Sloan Digital Sky Survey. An r-band image of the field surrounding PHL 1811 recorded by the ACS instrument on HST shows that two galaxies at the same redshift as the gas are S0 galaxies, separated by only 34 and 87 h kpc from the line of sight. One or both of these galaxies may be the source of the material in the Lyman limit system, which may have been expelled from them in a fast wind, by tidal stripping, or by ram pressure stripping. Subtraction of the ACS point-spread function from the image of the QSO reveals the presence of a face-on spiral galaxy under the glare of the quasar; while it is possible that this galaxy may be responsible for the Lyman limit absorption, the exact alignment of the QSO with the center of the galaxy suggests that the spiral is the quasar host.
A generalized cut-set bound for deterministic multi-flow networks and its applications

We present a new outer bound for the sum capacity of general multi-unicast deterministic networks. Intuitively, this bound can be understood as applying the cut-set bound to concatenated copies of the original network with a special restriction on the allowed transmit signal distributions. We first study applications to finite-field networks, where we obtain a general outer-bound expression in terms of ranks of the transfer matrices. We then show that, even though our outer bound is for deterministic networks, a recent result relating the capacity of AWGN KxKxK networks and the capacity of a deterministic counterpart allows us to establish an outer bound to the DoF of KxKxK wireless networks with general connectivity. This bound is tight in the case of the "adjacent-cell interference" topology, and yields graph-theoretic necessary and sufficient conditions for K DoF to be achievable in general topologies.
Diagnosing the top-quark angular asymmetry using LHC intrinsic charge asymmetries

Flavor-violating interactions involving new heavy particles are among proposed explanations for the $t\overline{t}$ forward-backward asymmetry observed at the Tevatron. Many of these models generate a $t\overline{t}$-plus-jet signal at the LHC. In this paper, we identify several new charge-asymmetric variables in $t\overline{t}j$ events that can contribute to the discovery of such models at the LHC. We propose a data-driven method for the background, largely eliminating the need for a Monte Carlo prediction of $t\overline{t}$-plus-jets, and thus reducing systematic errors. With a fast detector simulation, we estimate the statistical sensitivity of our variables for one of these models, finding that charge-asymmetric variables could materially assist in the exclusion of the Standard Model (SM) across much of the mass and coupling range, given 5 inverse fb of data. Should any signal appear, our variables will be useful in distinguishing classes of models from one another.
ENERGY STAR product specification development framework: using data and analysis to make program decisions

The Product Development Team (PD) in the US Environmental Protection Agency's ENERGY STAR Labeling Program fuels the long-term market transformation process by delivering new specifications. PD's goal is to expand the reach and visibility of ENERGY STAR as well as the market for new energy-efficient products. As of 2002, PD has launched nine new ENERGY STAR specifications and continues to evaluate new program opportunities. To evaluate the ENERGY STAR potential for a diverse group of products, PD prepared a framework for developing new and updating existing specifications that rationalizes new product opportunities and draws upon the expertise and resources of other stakeholders. Manufacturers and stakeholders have a vested interest in understanding how ENERGY STAR products are selected for labeling. In this article, we explore in depth PD's process and also provide two case studies that illustrate the application of PD's framework. After 3 years of implementation, several lessons learned have emerged. Manufacturers are increasingly inquiring as to why a product is/is not labeled. Careful application of the framework allows PD to justify program decisions. PD increasingly recognizes that each industry has unique market and product characteristics that can require reconciliation with the guidelines of the ENERGY STAR program. Careful application of the framework identifies where reconciliation is needed to preserve the program integrity and justify decisions. Finally, to date, the application of the framework has enabled PD to navigate through complex product issues and make consistent specification development decisions.
Roadside particle number distributions and relationships between number concentrations, meteorology, and traffic along a northern California freeway.

Abstract Particle number distributions were bimodal, with a primary within 10 m of the traveled lanes. mode at ∼10–25 nm, indicating that newly formed particles were sampled. Total downwind 6–237 nm particle number concentrations (N tot) ranged from 9.3 × 103 to 2.5 × 105 cm−3, with higher daily average concentrations in November compared with July. Ntot correlated with wind speed, temperature, and relative humidity. Upwind photochemically initiated nucleation likely led to elevated background nanoparticle concentrations in July, as evidenced by increasing upwind distribution modal diameter with increasing temperature and a strong correlation between upwind N tot and solar radiation. Also in summer, N tot showed stronger correlation with Particle number distributions were measured simultaneously upwind and downwind of a suburban-agricultural freeway to determine relationships with traffic and meteorological parameters. Average traffic volumes were 6330 vehicles/hr with 10% heavy-duty vehicles, and volumes...
Main group atranes: chemical and structural features

Abstract Atranes are comprised of two bridgehead atoms bridged by three three-atom moieties. When the bridgehead atoms interact, a [3.3.3.0] tricyclic system is produced; when they do not, a [3.3.3] bicyclic structure is evident. Quasi-tricyclic structures are also known in which the bridgehead-bridgehead bond length lies between the sum of the van der Waals radii and a normal transannular bond. Because of this and additional factors, atranes give rise to interesting new and useful chemistry as well as novel molecular architectures. In this review the chemical reactivities and structural properties of main group atrane systems are surveyed.
Calculation of a three-dimensional locally elliptic flow with a zonal equation method

The Navier-Stokes equatons are elliptic or time hyperbolic, but parabolizing assumptions can be made under certain conditions leading to various boundary-layer and space-marching formulations that can greatly accelerate the solution time. A zonal equation method is presented which uses zones where ellipticity is high for solution by Navier-Stokes methods, and zones where parabolizing assumptions are valid for solution by space-marching techniques. The concept of localized ellipticity is explored and evaluated.
Multibody dynamic simulation of the next generation space telescope using finite elements and fuzzy sets

Abstract Multibody dynamic simulations are performed for a large deployable space structure using finite element models and an explicit temporal integration procedure. The structure considered is NASA's light-weight, 8 m-aperture next generation space telescope (NGST). The NGST structure consists of beam components (modeled using beam “super-elements”, each composed of two truss elements and a torsional spring), thin-surface shell-type components (modeled using super-elements, each composed of one brick, twelve truss elements, and six surface elements), revolute and prismatic joints, and reaction wheels. Detailed numerical simulations are conducted for the vibrational response, attitude control, and deployment. A fuzzy-set technique is used to assess the effect of changing the dwell time of the various deployment actuators on the total strain energy of the structure.
Calculation of photoelectron spectra of group IV tetrachlorides and carbon tetrahalides by SCF-Xα-SW method

Photoelectron spectra and one-electron eigenfunctions of group IV tetrachlorides, ACl4, where A = C, Si, Ge, Sn and carbon tetrahalides, CB4, where B = F, Cl, Br, I, have been calculated by SCF-Xα-SW method. Excellent agreement is obtained with the observed photoelectron spectra. The radius reduction factors of atomic sphereFrwere adjusted instead of changing individual atomic radii. The comparison of photoelectron spectra and one-electron eigenfunctions for molecules ACl4 for different central atoms A and halogen atoms B is discussed.
Neutrino Transport in Strongly Magnetized Proto-Neutron Stars and the Origin of Pulsar Kicks: The Effect of Asymmetric Magnetic Field Topology

In proto-neutron stars with strong magnetic fields, the cross section for νe (${u{{ν}}{"7016}}$ --> -->e) absorption on neutrons (protons) depends on the local magnetic field strength resulting from the quantization of energy levels for the e- (e+) produced in the final state. If the neutron star possesses an asymmetric magnetic field topology in the sense that the magnitude of magnetic field in the north pole is different from that in the south pole, then asymmetric neutrino emission may be generated. We calculate the absorption cross sections of νe and ${u{{ν}}{"7016}}$ --> -->e in strong magnetic fields as a function of the neutrino energy. These cross sections exhibit oscillatory behaviors that occur because new Landau levels for the e- (e+) become accessible as the neutrino energy increases. By evaluating the appropriately averaged neutrino opacities, we demonstrate that the change in the local neutrino flux caused by the modified opacities is rather small. To generate appreciable kick velocity (~300 km s-1) to the newly formed neutron star, the difference between the field strengths at the two opposite poles of the star must be at least 1016 G. We also consider the magnetic field effect on the spectral neutrino energy fluxes. The oscillatory features in the absorption opacities give rise to modulations in the emergent spectra of νe and ${u{{ν}}{"7016}}$ --> -->e.
Vibrational spectra of dioxygen adducts of metal chelate compounds

Cet article presente l'analyse spectrale IR de metalloproteines dioxygenees: cytochrome P-450, hemocyanines, hemerythrines, myoglobine et hemoglobine ou de composes analogues
EFFECTS OF ELEVATED TEMPERATURES ON PERFORMANCE OF A COMPLEX MENTAL TASK

Eleven subjects wore tested on a complex mental task during one-hour exposures to four different dry bulb/wet bulb temperature conditions : 85°/75°, 90°/80°, 95°/85° and 100°/90°F. In a second experiment, ten subjects were tested at 85°/75°, 90°/80°, 110°/90° and 120°/90°F. In both experiments, differences in performance among the temperature conditions were small and not significant.
Indicators of black-hole mass and Eddington accretion ratio from QSO X-ray and UV spectra

Abstract The evolution of luminous QSOs is linked to the evolution of massive galaxies. We know this because the relic black-holes found locally have masses dependent on the properties of the host galaxy’s bulge. An important way to explore this evolution would be to measure dependences of black-hole masses and Eddington accretion ratios over a range of redshifts, i.e., with cosmological age. For low redshift QSOs (and their lower luminosity Seyfert galaxy counterparts) it has been possible to infer black-hole masses from the luminosities and velocity dispersions of their host-galaxy bulges. These masses agree with those virial black-hole masses calculated from the Doppler widths of the broad Hβ emission lines. The latter method can then be extended to more distant and luminous QSOs, up to redshifts of 0.6 with ground-based optical observations. We discuss ways to extend these explorations to higher redshifts – up to ∼3 using the widths of QSOs’ broad UV emission lines, and in principle, and to redshifts near 4 from ground-based infrared observations of rest-frame Hβ at 2.5 μm. We discuss the possibility of investigating the accretion history of the higher redshift QSOs using measures of Eddington accretion ratio – the soft X-ray spectral index and the eigenvectors of Principal Components Analyses of QSOs’ UV emission-line spectra.
A Convenient One-Step Gingerol Synthesis

Abstract Racemic 6-gingerol can be obtained in a one-pot reaction by hexanal addition to the dianion of zingerone at low temperature. Similarly, addition of octanal or decanal to the dianion provides 8-gingerol or 10-gingerol, respectively. Acid treatment of the gingerols allows for formation of the corresponding shogaols.
Enantioselective Construction of Pyrrolidines by Palladium-Catalyzed Asymmetric [3+2] Cycloaddition of Trimethylenemethane with Imines

A protocol for the enantioselective [3 + 2] cycloaddition of trimethylenemethane (TMM) with imines has been developed. Central to this effort were the novel phosphoramidite ligands developed in our laboratories. The conditions developed to effect an asymmetric TMM reaction using 2-trimethylsilylmethyl allyl acetate were shown to be tolerant of a wide variety of imine acceptors to provide the corresponding pyrrolidine cycloadducts with excellent yields and selectivities. Use of a bis-2-naphthyl phosphoramidite allowed the successful cycloaddition of the parent TMM with N-Boc imines, and has further permitted the reaction of substituted donors with N-tosyl aldimines and ketimines in high regio-, diastereo-, and enantioselectivity. Use of a diphenylazetidine ligand allows the complementary synthesis of the exocyclic nitrile product shown, and we demonstrate control of the regioselectivity of the product based on manipulation of the reaction parameters.