cssi/SciSciGPT-SciSciNet huggingface dataset:
A New Milky Way Companion: Unusual Globular Cluster or Extreme Dwarf Satellite?

We report the discovery of SDSS J1049+5103, an overdensity of resolved blue stars at (α2000, δ2000) = (162343, 51051). This object appears to be an old, metal-poor stellar system at a distance of 45 ± 10 kpc, with a half-light radius of 23 ± 10 pc and an absolute magnitude of MV = -3.0. One star that is likely associated with this Milky Way companion has an SDSS spectrum confirming it as a blue horizontal-branch star at 48 kpc. The color-magnitude diagram of SDSS J1049+5103 contains few, if any, horizontal or red giant branch stars, similar to the anomalously faint globular cluster AM 4. The size and luminosity of SDSS J1049+5103 places it at the intersection of the size-luminosity relationships followed by known globular clusters and by Milky Way dwarf spheroidal galaxies. If SDSS J1049+5103 is a globular cluster, then its properties are consistent with the established trend that the largest radius Galactic globular clusters are all in the outer halo. However, the five known globular clusters with similarly faint absolute magnitudes all have half-mass radii that are smaller than SDSS J1049+5103 by a factor of 5. If it is a dwarf spheroidal galaxy, then it is the faintest yet known by 2 orders of magnitude and is the first example of the ultrafaint dwarfs predicted by some theories. The uncertain nature of this new system underscores the sometimes ambiguous distinction between globular clusters and dwarf spheroidal galaxies. A simple friends-of-friends search for similar, blue, small scale length star clusters detected all known globular clusters and dwarfs closer than 50 kpc in the SDSS area but yielded no other candidates as robust as SDSS J1049+5103.
Residues and filtered D-modules

For an embedding of sufficiently high degree of a smooth projective variety X into projective space, we use residues to define a filtered holonomic \({\mathcal{D}}\) -module \({(\mathcal{M}, F)}\) on the dual projective space. This gives a concrete description of the intermediate extension to a Hodge module on P of the variation of Hodge structure on the middle-dimensional cohomology of the hyperplane sections of X. We also establish many results about the sheaves \({F_k{\mathcal{M}}}\) , such as positivity, vanishing theorems, and reflexivity.
Note on the asymptotic approximation of a double integral with an angular-spectrum representation

Abstract In this note, we are concerned with the asymptotic approximation of a class of double integrals which can be represented as an angular-spectrum superposition. These double integrals typically appear in electromagnetic scattering problems. Based on the synthetic manipulation of the method of steepest descent path, approximate expressions of the double integrals are derived in terms of the leading term of the contribution to the asymptotic expansions.
Fast dye salts provide fast access to azidoarene synthons in multi-step one-pot tandem click transformations

Abstract This study examined whether commercially available diazonium salts could be used as efficient aromatic azide precursors in one-pot multi-step click transformations. Seven different diazonium salts, including Fast Red RC, Fast Blue B, Fast Corinth V and Variamine Blue B were surveyed under aqueous click reaction conditions of CuSO 4 /Na ascorbate catalyst with 1:1 t -BuOH/H 2 O solvent. Two-step tandem reactions with terminal alkyne and diyne co-reactants led to 1,2,3-triazole products in 66–88% yields, while three-step tandem reactions with trimethylsilyl-protected alkyne and diyne co-reactants led to 1,2,3-triazole products in 61–78% yields.
Eruptive disseminated porokeratosis associated with corticosteroid-induced immunosuppression

Eruptive disseminated porokeratosis (EDP) is a disease that presents clinically with sudden onset of erythematous papules and plaques, with a ridge-like border histologically represented by a cornoid lamella. We report a case of EDP occurring in a 39-year-old woman 3 days after completion of a 2-week course of oral corticosteroid therapy for an acute asthma exacerbation. The patient was treated with emollients and sun protection. Unlike the more chronic disseminated superficial (actinic) porokeratosis, EDP secondary to immunosuppression from corticosteroid therapy has very rarely been reported in the dermatological literature.
Rebuilding the Cepheid Distance Scale. I. A Global Analysis of Cepheid Mean Magnitudes

We develop a statistical method for using multicolor photometry to determine distances using Cepheid variables, including the effects of temperature, extinction, and metallicity, and apply it to UBVRIJHK photometry of 694 Cepheids in 17 galaxies. We derive homogeneous distance, extinction, and uncertainty estimates for four models, starting from the standard extragalactic method and then adding the physical effects of temperature distributions and extinction distributions, requiring positive definite extinctions and metallicity. While we find general agreement with published distances when we make similar systematic assumptions, there is a clear problem in the standard distances because they require Cepheids with negative extinctions, particularly in low-metallicity galaxies, unless the mean LMC extinction exceeds E(B - V) 0.20. The problem can be explained by the physically expected metallicity dependence of the Cepheid distance scale, where metal-poor Cepheids are hotter and possibly fainter at V and I than metal-rich Cepheids, or by large systematic errors in Cepheid photometry. For V and I we found that the mean magnitude change is -0.14 ± 0.14 mag dex-1 and the mean color change is 0.13 ± 0.04 mag dex-1, with the change in color dominating the change in distance. The effect on Type Ia supernova estimates of the Hubble constant is dramatic because most were found in the metal-poor galaxies with the bluest Cepheids. The Type Ia multicolor light-curve shape method estimate for H0 formally rises from 69 ± 8 to 80 ± 6 km s-1 Mpc-1 with the metallicity correction.
Profiling microRNA expression in Arabidopsis pollen using microRNA array and real-time PCR

Background: MicroRNAs (miRNAs) are ~22-nt small non-coding RNAs that regulate the expression of specific target genes in many eukaryotes. In higher plants, miRNAs are involved in developmental processes and stress responses. Sexual reproduction in flowering plants relies on pollen, the male gametophyte, to deliver sperm cells to fertilize the egg cell hidden in the embryo sac. Studies indicated that post-transcriptional processes are important for regulating gene expression during pollen function. However, we still have very limited knowledge on the involved gene regulatory mechanisms. Especially, the function of miRNAs in pollen remains unknown. Results: Using miRCURY LNA array technology, we have profiled the expression of 70 known miRNAs (representing 121 miRBase IDs) in Arabidopsis mature pollen, and compared the expression of these miRNAs in pollen and young inflorescence. Thirty-seven probes on the array were identified using RNAs isolated from mature pollen, 26 of which showed significant differences in expression between mature pollen and inflorescence. Real-time PCR based on TaqMan miRNA assays confirmed the expression of 22 miRNAs in mature pollen, and identified 8 additional miRNAs that were expressed at low level in mature pollen. However, the expression of 11 miRNA that were identified on the array could not be confirmed by the Taqman miRNA assays. Analyses of transcriptome data for some miRNA target genes indicated that miRNAs are functional in pollen. Conclusion: In summary, our results showed that some known miRNAs were expressed in Arabidopsis mature pollen, with most of them being low abundant. The results can be utilized in future research to study post-transcriptional gene regulation in pollen function.
Expand or retrench? Alliance portfolio adaptation to environmental jolts

We assume the real options perspective and threat–rigidity model to explain firms' responses to different environmental changes. Treating firms' alliance portfolios as bundles of real options, we argue firms would expand both the size and diversity of their alliance portfolios when environmental change is perceived to be creating opportunities; but both the size and diversity of their alliance portfolios shrink when an environmental change is perceived as posing threats. We tested our hypotheses by tracing the evolution of telecom industry firms' alliance portfolio strategy during and after the 1996 Telecommunications Act and the year 2000 dot.com and financial markets crash.
Optimal delegated portfolio management with background risk

Abstract Most investors delegate the management of a fraction of their wealth to portfolio managers who are given the task of beating a benchmark. However, in an influential paper [Roll, R., 1992. A mean/variance analysis of tracking error. Journal of Portfolio Management 18, 13–22] shows that the objective functions commonly used by these managers lead to the selection of portfolios that are suboptimal from the perspective of investors. In this paper, we provide an explanation for the use of these objective functions based on the effect of background risk on investors’ optimal portfolios. Our main contribution is to provide conditions under which investors can optimally delegate the management of their wealth to portfolio managers.
Exploring Halo Substructure with Giant Stars: The Dynamics and Metallicity of the Dwarf Spheroidal in Boötes

We report the results of a spectroscopic study of the Bootes (Boo) dwarf spheroidal (dSph) galaxy carried out with the WIYN telescope and the Hydra multifiber spectrograph. Radial velocities have been measured for 58 Boo candidate stars selected to have magnitudes and colors consistent with its red and asymptotic giant branches. Within the 13' half-light radius, seven members of Boo yield a systemic velocity of Vr = 95.6 ± 3.4 km s-1 and a velocity dispersion of σ0 = 6.6 ± 2.3 km s-1. This implies a mass on the order of 1 × 107 M☉, similar to the inferred masses of other Galactic dSphs. Adopting a total Boo luminosity of L = 1.8 × 104 to 8.6 × 104 L☉ implies M/L ~ 610-130, making Boo, the most distorted known Milky Way dwarf galaxy, potentially also the darkest. From the spectra of Boo member stars we estimate its metallicity to be [Fe/H] ~ -2.5, which would make it the most metal-poor dSph known to date.
Testing the Relation between the Local and Cosmic Star Formation Histories

Recently, there has been great progress toward observationally determining the mean star formation history of the universe. When accurately known, the cosmic star formation rate could provide much information about Galactic evolution, if the Milky Way's star formation rate is representative of the average cosmic star formation history. A simple hypothesis is that our local star formation rate is proportional to the cosmic mean. In addition, to specify a star formation history, one must also adopt an initial mass function (IMF); typically it is assumed that the IMF is a smooth function, which is constant in time. We show how to test directly the compatibility of all these assumptions by making use of the local (solar neighborhood) star formation record encoded in the present-day stellar mass function. Present data suggest that at least one of the following is false: (1) the local IMF is constant in time; (2) the local IMF is a smooth (unimodal) function; and/or (3) star formation in the Galactic disk was representative of the cosmic mean. We briefly discuss how to determine which of these assumptions fail and also improvements in observations, which will sharpen this test.
The Multiplicity Polar Theorem and isolated singularities

Recently there has been much work done in the study of isolated singularities. The singularities may be those of sets, functions, vector fields or differential forms. Examples can be found in the references at the end of this paper. In these works the authors have developed algebraic invariants which describe the isolated singularity. In this paper, we show how many of these invariants can be computed by relating them to the multiplicity of a pair of modules, by means of the multiplicity polar theorem. The method of application is the same in all cases. A deformation is constructed in which the isolated singularity breaks into the simplest possible singularities, which are well understood, and the multiplicity polar theorem relates the multiplicity of the pair of modules in the original situation to the multiplicities at the simple points. Our answer involves a pair of modules because the the multiplicity is only defined for modules and ideals of finite colength, and in many of the situations we want to describe the modules do not have finite colength. The solution to this problem is to use pairs of modules, (M, N), where M ⊂ N ⊂ O p X,x ; here M has finite colength in N, N is the ”least complicated” module in O p X,x consistent with the geometry of X that makes the colength of M infinite. The difference between M and N, which is measured by the multiplicity of the pair, should reflect only the contribution of the geometry at the point x. This geometry can be related to other invariants of X by using an N which reflects some of the geometry of X at the point, then using the additivity property of multiplicity to relate the multiplicities of the pairs. This is illustrated in propositions 2.5 and 2.6. The first application is to the study of the Euler obstruction. The Euler Obstruction is the basic tool used by MacPherson in constructing a Chern class on singular spaces. (Cf.[10], [1] for details.) ˜ ′
Third World Military Expenditure: Determinants and Implications

Military expenditure - a descriptive profile research design military expenditure and power capabilities military expenditure and budgetary behaviour military expenditure and international interactions military expenditure and domestic conflict military expenditure and interstate conflict military expenditure and national security.
A Two-Tiered On-Line Server-Side Bandwidth Reservation Framework for the Real-Time Delivery of Multiple Video Streams

National Science Foundation (CISE/CSR 0720604, ENG/EFRI 0735974, CISE/CNS 0524477, CNS/NeTS 0520166, CNS/ITR 0205294, CISE/EIA RI 02020670; Universidad Pontificia Bolivariana; COLCIENCIAS–Instituto Colombiano para el Desarrollo de la Ciencia y la Tecnologia "Francisco Jose de Caldas"
Continuation-based multiprocessing

Any multiprocessing facility must include three features: elementary exclusion, data protection, and process saving. While elementary exclusion must rest on some hardware facility (e.g. a test-and-set instruction), the other two requirements are fulfilled by features already present in applicative languages. Data protection may be obtained through the use of procedures (closures or funargs),and process saving may be obtained through the use of the CATCH operator. The use of CATCH, in particular, allows an elegant treatment of process saving.We demonstrate these techniques by writing the kernel and some modules for a multiprocessing system. The kernel is very small. Many functions which one would normally expect to find inside the kernel are completely decentralized. We consider the implementation of other schedulers, interrupts, and the implications of these ideas for language design.
Secure communication over fading channels with statistical QoS constraints

In this paper, secure transmission of information over an ergodic fading channel is studied in the presence of statistical quality of service (QoS) constraints.We employ effective capacity to measure the secure throughput of the system, i.e., effective secure throughput. We assume that the channel side information (CSI) of the main and the eavesdropper channels is available at the transmitter side. Under this assumption, we investigate the optimal power control policies that maximize the effective secure throughput. In particular, it is noted that opportunistic transmission is no longer optimal and the transmitter should not wait to send the data at a high rate until the main channel is much better than the eavesdropper channel. Moreover, it is shown that the benefits of adapting the power with respect to the CSI of both the eavesdropper and main channels rather than the CSI of only the main channel diminish as QoS constraints become more stringent.
A scaling theory of bifurcations in the symmetric weak-noise escape problem

We consider two-dimensional overdamped double-well systems perturbed by white noise. In the weak-noise limit the most probable fluctuational path leading from either point attractor to the separatrix (the most probable escape path, or MPEP) must terminate on the saddle between the two wells. However, as the parameters of a symmetric double-well system are varied, a unique MPEP may bifurcate into two equally likely MPEPs. At the bifurcation point in parameter space, the activation kinetics of the system become non-Arrhenius. We quantify the non-Arrhenius behavior of a system at the bifurcation point, by using the Maslov-WKB method to construct an approximation to the quasistationary probability distribution of the system that is valid in a boundary layer near the separatrix. The approximation is a formal asymptotic solution of the Smoluchowski equation. Our construction relies on a new scaling theory, which yields “critical exponents” describing weak-noise behavior at the bifurcation point, near the saddle.
Supports of irreducible spherical representations of rational Cherednik algebras of finite Coxeter groups

Abstract In this paper we determine the support of the irreducible spherical representation (i.e., the irreducible quotient of the polynomial representation) of the rational Cherednik algebra of a finite Coxeter group for any value of the parameter c . In particular, we determine for which values of c this representation is finite dimensional. This generalizes a result of Varagnolo and Vasserot (2009) [20] , who classified finite dimensional spherical representations in the case of Weyl groups and equal parameters (i.e., when c is a constant function). Our proof is based on the Macdonald–Mehta integral and the elementary theory of distributions.
Chromium aminocarbene complexes in organic synthesis

Abstract The synthesis, the physical and spectroscopic properties, and the thermal and photochemical reactions of chromium aminocarbene complexes are reviewed, with an emphasis on the authors' research in the area.
A family of bijections between G -parking functions and spanning trees

For a directed graph G on vertices {0, 1, ..., n}, a G-parking function is an n-tuple (b1,...,bn) of non-negative integers such that, for every non-empty subset U ⊆ {1,...,n}, there exists a vertex j ∈ U for which there are more than bj edges going from j to G - U. We construct a family of bijective maps between the set PG of G-parking functions and the set JG of spanning trees of G rooted at 0, thus providing a combinatorial proof of |PG| = |JG|.
Radar ambiguity function, time-varying matched filter, and optimum wavelet correlator

We review the relation between the radar ambiguity function and the matched filter, and then introduce a geometric concept of the matched filter as a slice of the ambiguity function along a frequency-shift line. With the help of this geometric concept, the conventional matched filter can be generalized to a time-varying matched filter, which is equivalent to the optimum time-frequency correlator and can be implemented with wavelet transforms. The application of the optimum wavelet correlator to the inverse synthetic aperture radar is illustrated.
A Functional-Analytic Theory of Vertex (Operator) Algebras, II

For a finitely-generated vertex operator algebra V of central charge cℂ, a locally convex topological completion HV is constructed. We construct on HV a structure of an algebra over the operad of the \({{\frac{{c}}{{2}}^{{\rm{ th}}}}}\) power Detc/2 of the determinant line bundle Det over the moduli space of genus-zero Riemann surfaces with ordered analytically parametrized boundary components. In particular, HV is a representation of the semi-group of the \({{\frac{{c}}{{2}}^{{\rm{ th}}}}}\) power Detc/2(1) of the determinant line bundle over the moduli space of conformal equivalence classes of annuli with analytically parametrized boundary components. The results in Part I for ℤ-graded vertex algebras are also reformulated in terms of the framed little disk operad. Using May’s recognition principle for double loop spaces, one immediate consequence of such operadic formulations is that the compactly generated spaces corresponding to (or the k-ifications of) the locally convex completions constructed in Part I and in the present paper have the weak homotopy types of double loop spaces. We also generalize the results above to locally-grading-restricted conformal vertex algebras and to modules.
A Delphi-Based Framework for systems architecting of in-orbit exploration infrastructure for human exploration beyond Low Earth Orbit☆

Abstract The current debate in the U.S. Human Spaceflight Program focuses on the development of the next generation of man-rated heavy lift launch vehicles. While launch vehicle systems are of critical importance for future exploration, a comprehensive analysis of the entire exploration infrastructure is required to avoid costly pitfalls at early stages of the design process. This paper addresses this need by presenting a Delphi-Based Systems Architecting Framework for integrated architectural analysis of future in-orbit infrastructure for human space exploration beyond Low Earth Orbit. The paper is structured in two parts. The first part consists of an expert elicitation study to identify objectives for the in-space transportation infrastructure. The study was conducted between November 2011 and January 2012 with 15 senior experts involved in human spaceflight in the United States and Europe. The elicitation study included the formation of three expert panels representing exploration, science, and policy stakeholders engaged in a 3-round Delphi study. The rationale behind the Delphi approach, as imported from social science research, is discussed. Finally, a novel version of the Delphi method is presented and applied to technical decision-making and systems architecting in the context of human space exploration. The second part of the paper describes a tradespace exploration study of in-orbit infrastructure coupled with a requirements definition exercise informed by expert elicitation. The uncertainties associated with technical requirements and stakeholder goals are explicitly considered in the analysis. The outcome of the expert elicitation process portrays an integrated view of perceived stakeholder needs within the human spaceflight community. Needs are subsequently converted into requirements and coupled to the system architectures of interest to analyze the correlation between exploration, science, and policy goals. Pareto analysis is used to identify architectures of interest for further consideration by decision-makers. The paper closes with a summary of insights and develops a strategy for evolutionary development of the exploration infrastructure of the incoming decades. The most important result produced by this analysis is the identification of a critical irreducible ambiguity undermining value delivery for the in-space transportation infrastructure of the next three decades: destination choice. Consensus on destination is far from being reached by the community at large, with particular reference to exploration and policy stakeholders. The realization of this ambiguity is a call for NASA to promote an open forum on this topic, and to develop a strong case for policy makers to incentivize investments in the human spaceflight industry in the next decades.
Intramolecular, Reductive Coupling of Bis-α,β-unsaturated Ketones

The reduction-rearrangement chemistry of two rigidly held doubly vinylogous β-diketones has been investigated. One hydrophenanthrene dienedione was a tricyclic intermediate in the Wilds total steroid synthesis and the other was prepared from the Wieland-Miescher ketone. Lithium-ammonia reduction yielded a cyclopropanedione and a cyclopropanoketol, respectively. Treatment of these compounds with acid furnished cyclopropane-cleaved ketoenones.
Drilling and producing operations utilizing a tension-leg platform

The Hutton field, discovered in 1973, is located in U.K. Block 211/28 about 275 miles (440 km) off the Shetland Islands in 485 ft (148 m) of water. The 1979 decision to proceed with field development was significant because the structure selected would become the world's first commercial tension-leg platform (TLP). This operational review covers the predrilling and completion of the first 10 wells from a semisubmersible drilling rig, their subsequent tieback to the TLP, and the startup activity from an integrated-deck philosophy with production operations from a platform with moving trees, flexible flowlines, and production riser tensioners.
Using Patents In Growth Models

This paper argues that macroeconomic models of endogenous growth driven by technological change could be much improved by drawing lessons from the microeconomic literature of intellectual property design. Growth models use overly simplistic and sometimes incorrect assumptions regarding the intellectual property regime. Microeconomic theory and empirical work are reviewed to demonstrate that determining optimal intellectual property design is complex and has important implications for firm behavior and performance. Considering the question of intellectual property design in a dynamic general equilibrium model should yield important insights about how intellectual property impacts growth and welfare.
Chemical and physical characterization of produced waters from conventional and unconventional fossil fuel resources

Characterization of produced waters (PWs) is an initial step for determining potential beneficial uses such as irrigation and surface water discharge at some sites. A meta-analysis of characteristics of five PW sources [i.e. shale gas (SGPWs), conventional natural gas (NGPWs), conventional oil (OPWs), coal-bed methane (CBMPWs), tight gas sands (TGSPWs)] was conducted from peer-reviewed literature, government or industry documents, book chapters, internet sources, analytical records from industry, and analyses of PW samples. This meta-analysis assembled a large dataset to extract information of interest such as differences and similarities in constituent and constituent concentrations across these sources of PWs. The PW data analyzed were comprised of 377 coal-bed methane, 165 oilfield, 137 tight gas sand, 4000 natural gas, and 541 shale gas records. Majority of SGPWs, NGPWs, OPWs, and TGSPWs contain chloride concentrations ranging from saline (>30 000 mg L−1) to hypersaline (>40 000 mg L−1), while most CBMPWs were fresh (<5000 mg L−1). For inorganic constituents, most SGPW and NGPW iron concentrations exceeded the numeric criterion for irrigation and surface water discharge, while OPW and CBMPW iron concentrations were less than the criterion. Approximately one-fourth of the PW samples in this database are fresh and likely need minimal treatment for metal and metalloid constituents prior to use, while some PWs are brackish (5000–30 000 mg Cl− L−1) to saline containing metals and metalloids that may require considerable treatment. Other PWs are hypersaline and produce a considerable waste stream from reverse osmosis; remediation of these waters may not be feasible. After renovation, fresh to saline PWs may be used for irrigation and replenishing surface waters.
Tax Subsidies to Owner-Occupied Housing: An Asset-Market Approach

Inflation reduces the effective cost of homeownership and raises the tax subsidy to owner occupation. This paper presents an asset-market model of the housing market and estimates how changes in the expected inflation rate affect the real price of houses and the equilibrium size of the housing capital stock. Simulation results suggest that the accelerating inflation of the 1970s, which substantially reduced homeowners' user costs, could have accounted for as much as a 30 percent increase in real house prices. Persistent high inflation rates could lead ultimately to a sizable increase in the stock of owner-occupied housing.
Coastal Atmospheric Circulation around an Idealized Cape during Wind-Driven Upwelling Studied from a Coupled Ocean–Atmosphere Model

Abstract The study analyzes atmospheric circulation around an idealized coastal cape during summertime upwelling-favorable wind conditions simulated by a mesoscale coupled ocean–atmosphere model. The domain resembles an eastern ocean boundary with a single cape protruding into the ocean in the center of a coastline. The model predicts the formation of an orographic wind intensification area on the lee side of the cape, extending a few hundred kilometers downstream and seaward. Imposed initial conditions do not contain a low-level temperature inversion, which nevertheless forms on the lee side of the cape during the simulation, and which is accompanied by high Froude numbers diagnosed in that area, suggesting the presence of the supercritical flow. Formation of such an inversion is likely caused by average easterly winds resulting on the lee side that bring warm air masses originating over land, as well as by air warming during adiabatic descent on the lee side of the topographic obstacle. Mountain leeside...
MIDAS regressions: Further results and new directions

We explore mixed data sampling (henceforth MIDAS) regression models. The regressions involve time series data sampled at different frequencies. Volatility and related processes are our prime focus, though the regression method has wider applications in macroeconomics and finance, among other areas. The regressions combine recent developments regarding estimation of volatility and a not-so-recent literature on distributed lag models. We study various lag structures to parameterize parsimoniously the regressions and relate them to existing models. We also propose several new extensions of the MIDAS framework. The paper concludes with an empirical section where we provide further evidence and new results on the risk–return trade-off. We also report empirical evidence on microstructure noise and volatility forecasting.
Vehicle Sorting for Platoon Formation: Impacts on Highway Entry and Throughput

Automated highway systems (AHS) are intended to increase the throughput and safety of roadways through computer control, communication and sensing. In the “platoon” concept for AHS, vehicles travel on highways in closely spaced groups. To maximize benefits, it is desirable to form platoons that are reasonably large (five or more vehicles), and it is also desirable to ensure that platoons remain intact for considerable distances. This paper develops and evaluates strategies for organizing vehicles into platoons at highway entrances, with the objective of maximizing the distance that platoons stay intact, so that they do not need to be regrouped into new platoons on the highway itself. Fundamentally, this entails grouping vehicles according to their destination. We evaluate various strategies in which vehicles are sorted on entrance ramps, with respect to platoon sizes, throughput and platoon formation time.
Sequential Bayesian inference in hidden Markov stochastic kinetic models with application to detection and response to seasonal epidemics

We study sequential Bayesian inference in stochastic kinetic models with latent factors. Assuming continuous observation of all the reactions, our focus is on joint inference of the unknown reaction rates and the dynamic latent states, modeled as a hidden Markov factor. Using insights from nonlinear filtering of continuous-time jump Markov processes we develop a novel sequential Monte Carlo algorithm for this purpose. Our approach applies the ideas of particle learning to minimize particle degeneracy and exploit the analytical jump Markov structure. A motivating application of our methods is modeling of seasonal infectious disease outbreaks represented through a compartmental epidemic model. We demonstrate inference in such models with several numerical illustrations and also discuss predictive analysis of epidemic countermeasures using sequential Bayes estimates.
Gauge mediated supersymmetry breaking and supergravity

Abstract We analyze simple models of gauge mediated supersymmetry breaking in the context of supergravity. We distinguish two cases. One is when the messenger of the supersymmetry breaking is a non Abelian gauge force and the other is when the messenger is a pseudoanomalous U (1). We assume that these models originate from string theory and we impose the constraint of the vanishing of the cosmological constant requiring also the stabilization of the dilaton. In the first case, we do not find vacua that are consistent with the constraints of gauge mediation and have a zero tree level cosmological constant. In the second case, no such conflict arises. In addition, by looking at the one loop cosmological constant, we show that the dilaton F -term can not be neglected in either case. For the gauge mediated case our considerations suggest that the dilaton must be frozen out of the low energy field theory by non-perturbative string dynamics.
New therapies for chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a major global health problem which is increasing throughout the world and a major cause of death. However, current therapies fail to prevent disease pr
Arabinofuranosyl Oligosaccharides from Mycobacteria: Synthesis and Effect of Glycosylation on Ring Conformation and Hydroxymethyl Group Rotamer Populations

A series of α-d-arabinofuranosyl oligosaccharides (2−8) that are fragments of the arabinan portions of two polysaccharides present in the cell wall of Mycobacterium tuberculosis have been synthesized. Preparation of the oligosaccharides involved the sequential addition of arabinofuranosyl residues from thioglycoside donors to methyl glycoside acceptors. High-resolution NMR studies on the final products provided all 3JH,H values, which were in turn used in PSEUROT 6.2 calculations to determine both the identity and equilibrium populations of preferred conformers for each furanose ring in these glycans. Comparison of the ring conformers present in 2−8 with those available in the parent monosaccharide, methyl α-d-arabinofuranose (16), allowed the determination of the effect of glycosylation upon ring conformation. At equilibrium, 16 exists as an approximately equimolar mixture of OT4 (North, N) and 2T3 (South, S) conformers. These studies showed that glycosylation of 16 at OH5 resulted in no significant chan...
Simulation of terrain propagation and diffraction using a 2D high-order accurate FMM-accelerated Nyström’s solver

In this paper, an FMM-accelerated and high-order accurate Nystorm's solver for analyzing wave propagation over large terrains with arbitrary profiles is implemented. The current implementation can be a valuable tool for validating existing asymptotic-based algorithms; in particular, it can be a convenient alternative for obtaining diffraction coefficient parameters, as is shown here for a canonical class of smooth dielectric surfaces.
On simplifications of certain q-multisums

Some examples of naturally arising multisum q-series which turn out to have representations as fermionic single sums are presented. The resulting identities are proved using transformation formulas from the theory of basic hypergeometric series.
Automation of antibody catalysis: a practical methodology for the use of catalytic antibodies in organic synthesis

Abstract The first large regio- and stereoselective synthesis catalyzed by an antibody is described which features automation as an attractive means for the general utilization of antibodies in larger reaction scales. A biphasic catalytic antibody system (5% aqueous hexane) is coupled with an automation device which facilitates the multigram synthesis of the desired compound.
Empirical Processes, Typical Sequences, and Coordinated Actions in Standard Borel Spaces

This paper proposes a new notion of typical sequences on a wide class of abstract alphabets (so-called standard Borel spaces), which is based on approximations of memoryless sources by empirical distributions uniformly over a class of measurable “test functions.” In the finite-alphabet case, we can take all uniformly bounded functions and recover the usual notion of strong typicality (or typicality under the total variation distance). For a general alphabet, however, this function class turns out to be too large, and must be restricted. With this in mind, we define typicality with respect to any Glivenko-Cantelli function class (i.e., a function class that admits a Uniform Law of Large Numbers) and demonstrate its power by giving simple derivations of the fundamental limits on the achievable rates in several source coding scenarios, in which the relevant operational criteria pertain to reproducing empirical averages of a general-alphabet stationary memoryless source with respect to a suitable function class.
A translation grammar for ALGOL 68

In this paper, a translation grammar is presented for a major subset of the ALGOL 68 programming language. This translation is from ALGOL 68 into an intermediate language that was originally designed for an EULER programming system. It appears that many of the ALGOL 68 programming facilities, especially the union declaration, the use of structures, and the manipulation of arrays with flexible dimension bounds can easily and naturally be expressed using EULER concepts along with some relatively straightforward EULER system procedures. Another advantage of using an EULER intermediate language is that implementations of the Euler system exist on the UNIVAC-1108, IBM-7094, Burroughs-6500, CDC-6500, and doubtless on the IBM-360 line of computers. Therefore, it would require a relatively modest effort for any organization having one of these computers to obtain a working "first version" of ALGOL 68.
Useful Catalytic Enantioselective Cationic Double Annulation Reactions Initiated at an Internal π-Bond: Method and Applications

The 1:1 complex of o,o′-dichloro-R-BINOL and SbCl5 initiates the enantioselective cationic polycyclization of polyunsaturated substrates at a predictable π-bond which may be either terminal or, as shown herein, internal. The extension of this powerful construction to internal π-bonds expands the scope of this method and opens up very short pathways to numerous chiral polycyclic molecules, including natural products and their analogues. Especially simple synthetic routes are disclosed that provide access to dysideapalaunic acid, dehydroabietic acid, and epipodocarpic acid and illustrate the value of this enantioselective approach.
NHC-Catalyzed Reactions of Aryloxyacetaldehydes: A Domino Elimination/Conjugate Addition/Acylation Process for the Synthesis of Substituted Coumarins

N-Heterocyclic carbenes (NHCs) catalyze a domino Michael addition/acylation reaction to form 3,4-dihydrocoumarins. The reaction proceeds through addition of the NHC to an aryloxyaldehyde followed by elimination of a phenoxide leaving group, generating an enol intermediate. This transient nucleophile generated in situ performs a 1,4-addition onto a conjugate acceptor, and the carbene catalyst is regenerated upon acylation of the phenoxide anion resulting in formation of 3,4-dihydrocoumarins.
Intermediate-term results of partial left ventriculectomy.

Partial left ventriculectomy (PLV) has been introduced as an option for patients with end-stage dilated cardiomyopathy. We report the result of a prospective trial of PLV in patients with idiopathic dilated cardiomyopathy, left ventricular end-diastolic diameter (LVEDD) > 7 cm, refractory New York Heart Association (NYHA) Class IV symptoms, and depressed exercise oxygen consumption studies. Sixteen patients underwent a PLV with a mean follow-up of 13 months. Fourteen patients were male. Mean age was 49.6 ± 10.5 years (range 30 to 67 years). Left ventricular ejection fraction (LVEF) improved after surgery from 13.9 ± 5.6 to 21.0 ± 8.4, and this improvement persisted for up to 12 months after operation. LVEDD and NYHA Class also were significantly improved after surgery and for up to 12 months of follow-up. Operative mortality was 6.25%. Twelve-month survival was 86% by Kaplan-Meier analysis. Four (25%) of 16 patients that had initial improvement after PLV developed recurrent heart failure and were listed for transplantation. Freedom from need for listing for heart transplantation was 65% at 12 months. Freedom from death or the need for relisting at 12 months was 56%. PLV can be performed with acceptable early and 12-month mortality. Significant improvements in LVEF, LVEDD, and NYHA Class are seen at up to 12 months of follow-up. Some patients will develop recurrent heart failure and require relisting for heart transplantation.
Blow up of subcritical quantities at the first singular time of the mean curvature flow

Consider a family of smooth immersions \({F(\cdot,t)\,:\,{M^n\to \mathbb{R}^{n+1}}}\) of closed hypersurfaces in \({\mathbb{R}^{n+1}}\) moving by the mean curvature flow \({\frac{\partial F(p,t)}{\partial t} = -H(p,t)\cdot \nu(p,t)}\), for \({t\in [0,T)}\). We show that at the first singular time of the mean curvature flow, certain subcritical quantities concerning the second fundamental form, for example \({\int_{0}^{t}\int_{M_{s}}\frac{{\vert{\it A}\vert}^{n + 2}}{ log (2 + {\vert{\it A}\vert})}} d\mu ds,\) blow up. Our result is a log improvement of recent results of Le-Sesum, Xu-Ye-Zhao where the scaling invariant quantities were considered.
Effect of Carbon Coating on Scuffing Performance in Diesel Fuels

Low-sulfur and low-aromatic diesel fuels are being introduced in order to reduce various types of emissions in diesel engines to levels in compliance with current and impending U.S. federal regulations. The low lubricity of these fuels, however, poses major reliability and durability problem for fuel injection components that depend on diesel fuel for their lubrication. In the present study, the authors evaluated the scuff resistance of surfaces in regular diesel fuel containing 500 ppm sulfur and in Fischer-Tropsch synthetic diesel fuel containing no sulfur or aromatics. Tests were conducted with the high frequency reciprocating test rig (HFRR) using 52100 steel balls and H-13 tool-steel flats with and without Argonne's special carbon coatings. Test results showed that the sulfur-containing fuels have about 20% higher scuffing resistance than does fuel without sulfur. The presence of the carbon coating on the flat increased scuffing resistance in both regular and synthetic fuels by about ten times, as me...
A GROUP WITH THREE REAL IRREDUCIBLE CHARACTERS: ANSWERING A QUESTION OF MORETÓ AND NAVARRO

In this paper, we construct a group with three real irreducible characters whose Sylow 2-subgroup is an iterated central extension of a Suzuki 2-group. This answers a question raised by Moreto and Navarro who asked whether such a group exists.
Oriented Quantum Algebras, Categories and Invariants of Knots and Links

This paper defines the concept of an oriented quantum algebra and develops its application to the construction of quantum link invariants. We show, in fact, that all known quantum link invariants can be put into this framework.
Formality theorems for Hochschild complexes and their applications

We give a popular introduction to formality theorems for Hochschild complexes and their applications. We review some of the recent results and prove that the truncated Hochschild cochain complex of a polynomial algebra is non-formal.
Integrability of Characteristic Hamiltonian Systems on Simple Lie Groups with Standard Poisson Lie Structure

Phase space of a characteristic Hamiltonian system is a symplectic leaf of a factorizable Poisson Lie group. Its Hamiltonian is a restriction to the symplectic leaf of a function on the group which is invariant with respect to conjugations. It is shown in this paper that such a system is always integrable.
MHD simulations of solar and interplanetary phenomena

Workers in the field of magnetohydrodynamics (MHD) have been interested in the hypothesis that observed solar activities can be utilized in a deterministic way to predict the bulk flow consequences of these activities in the three-dimensional heliosphere. Exploration of this hypothesis, using the conventional/classic initial boundary value approach, will be reviewed against the background of basic, ideal (except for shocks) one-fluid approximations. This work has been divided into two parts: near-Sun simulations in two dimensions of coronal mass ejections (CMEs) as well as interplanetary simulations in 2D and 3D of propagating shocks. In the latter case, the flows behind the shocks should be thought of as interplanetary “ICMEs”, i.e., the interplanetary, evolutionary consequences of the near-Sun simulations.
Geometry of power flows in tree networks

We investigate the problem of power flow and its relationship to optimization in tree networks. We show that due to the tree topology of the network, the general optimal power flow problem simplifies greatly. Our approach is to look at the injection region of the power network. The injection region is simply the set of all vectors of bus power injections that satisfy the network and operation constraints. The geometrical object of interest is the set of Pareto-optimal points of the injection region, since they are the solutions to the minimization of increasing functions. We view the injection region as a linear transformation of the higher dimensional power flow region, which is the set of all feasible power flows, one for each direction of each line. We show that if the voltage magnitudes are fixed, then the injection region becomes a product of two-bus power flow regions, one for each line in the network. Using this decomposition, we show that under the practical condition that the angle difference across each line is not too large, the set of Pareto-optimal points of the injection region remains unchanged by taking the convex hull. Therefore, the optimal power flow problem can be convexified and efficiently solved. This result improves upon earlier works since it does not make any assumptions about the active bus power constraints. We also obtain some partial results for the variable voltage magnitude case.
The exchange rate system and macroeconomic fluctuations in Sub-Saharan Africa

Abstract In this paper, we investigate the sources of macroeconomic fluctuations in Sub-Saharan African (SSA) countries with particular attention to the exchange rate system. We use a structural Vector Autoregression (VAR) model with limited capital mobility and long run restrictions to identify the shocks. Supply and terms of trade shocks tend to dominate output movements in the CFA and non-CFA countries alike. However, terms of trade shocks tend to influence the CFA zone to a greater extent and there seems to be a higher influence of demand shocks on output and the real exchange rates in the non-CFA countries.
Reduction of the two body problem in N = 2 Chern-Simons supergravity

Abstract By an extension of the methods used for the reduction of the two body problem in 2+1 dimensional gravity, we show that the two body problem in N = 2 Chern-Simons supergravity can be reduced exactly to an equivalent one body formalism. We give exact expressions for the invariants of the reduced one body problem.
Quasinormal modes of large AdS black holes

We develop a perturbative approach to the solution of the scalar wave equation for a large AdS black hole. In three dimensions, our method coincides with the known exact solution. We discuss the five-dimensional case in detail and apply our procedure to the Heun equation. We calculate the quasinormal modes analytically and obtain good agreement with numerical results for the low-lying frequencies.