cssi/SciSciGPT-SciSciNet huggingface dataset:
The Relation Between Security Returns, Firm Earnings, and Industry Earnings*

Abstract. In this paper we examine the relation between a firm's stock return and the earnings of other firms in the same industry, controlling for the firm's own earnings. We present a model in which the sign of this relation depends on the relative uncertainty there is about the size of the total industry value versus the division of that value between firms. We document considerable cross-industry variation in the relation between a firm's return and other firms' earnings, and demonstrate empirically that the sign of the relation depends on information provided prior to the industry earnings announcement period. Resume. Les auteurs examinent la relation entre le rendement de l'action d'une societe et les benefices des entreprises appartenant au meme secteur d'activite, en veillant a controler les benefices de la societe en question. Dans le modele qu'ils proposent, le sens (positif ou negatif) de cette relation depend de l'incertitude relative qui caracterise l'importance de la valeur globale du secteur d'activite par rapport au partage de cette valeur entre les entreprises qui le constituent. Les auteurs ont recueilli quantite d'information confirmant l'existence d'une forte variation dans la relation entre le rendement des actions d'une entreprise et les benefices des autres entreprises d'un meme secteur; ils demontrent aussi empiriquement que le sens de la relation depend de l'information produite avant la periode ou les benefices du secteur sont communiques.
Nuclear magnetic resonance in the heavy fermion superconductors

Nuclear magnetic resonance has emerged as a vital technique for investigating strongly correlated electron systems, and is particularly important for studying superconductivity. In this paper the basic features of NMR as a technique for probing the superconducting state are reviewed. Topics include spin relaxation processes, studies of vortex lattices and phenomena associated with unconventional pairing symmetries. Recent experimental work is reviewed, with a particular emphasis on the heavy fermion superconductors.
The reaction of the highly functionalized copper reagents RCu(CN)ZnI.BF3 with aldehydes

Abstract The new copper reagent RCu(CN)ZnI 2, which may contain important functional groups like the ester, nitrile, enoate or imide group, react in the presence of BF3.OEt2 with aldehydes to afford polyfunctional secondary alcohols in good yields (68–93%).
Asymmetric approaches to 1,2-disubstituted mitosenes based on the intramolecular cyclization of diazoesters

Abstract A strategy for the asymmetric synthesis of 1,2-disubstituted mitosenes is described. The key reaction is the decomposition of a meso diazoester in the presence of chiral copper(I) catalysts. Cyclization of diazoesters derived from (1R, 2S, 5R)-menthol and (R)-pantolactone provide optically pure 1,2-disubstituted mitosenes following oxidation and purification by flash chromatography.
A line scanning system controlled from an on-line console

Direct graphical input is one of the newest and most exciting sources of digital computer input. Programming techniques and hardware are beginning to appear which are designed to automatically process graphic information. This paper describes an experimental system which has been designed to facilitate the digitizing of line images. The equipment which is used for this purpose is an IBM 7960 Special Image Processing System consisting of graphic console, image processor, and a modified data channel. The image processor (Figure 1) contains a programmable Cathode Ray Tube (CRT) scanner, a CRT recorder, a 35mm camera, and film processing equipment.
Meditation effects on cognitive function and cerebral blood flow in subjects with memory loss: a preliminary study.

Meditation has long been defined as a potential technique for improving memory and lowering levels of stress, depression, and anxiety. Until now, there have been a few treatment options for patients with early cognitive impairment. Several medications and vaccine trials are underway. In one of the studies conducted Lutz and their team showed that expert meditators were able to induce changes in their brain activity during meditation with the help of electroencephalography. doi : 10.5214/ans.0972.7531.12190207
Irreducible many-body Casimir energies of intersecting objects

The vacuum energy of bosonic fields interacting locally with objects is decomposed into irreducible many-body parts. The irreducible N-body contribution is finite if the N objects have no common intersection, O1∩O2···∩ ON = ∅. The perturbative high-temperature expansion of the corresponding irreducible N-body spectral function N(β ~ 0) vanishes to all orders even if some of the objects overlap. These irreducible spectral functions and their associated Casimir energies can, in principle, be computed numerically or approximated semi-classically without regularization or implicit knowledge of the spectrum. They are analytic in the parameters describing the relative orientation and position of the individual objects and remain finite when some, but not all, of the N objects overlap. The finiteness of the irreducible N-body Casimir energy of a massless scalar field with potential scattering is explicitly verified and found to be negative for an even, and positive for an odd number of objects. The sign in this case does not depend on the strength of the local N-body potentials. Some simple examples illustrate the analyticity of N-body Casimir energies. A multiple scattering representation of the irreducible three-body Casimir energy is derived. It remains finite when the three objects overlap only pairwise.
On the dynamic programming principle for uniformly nondegenerate stochastic differential games in domains and the Isaacs equations

We prove the dynamic programming principle for uniformly nondegenerate stochastic differential games in the framework of time-homogeneous diffusion processes considered up to the first exit time from a domain. In contrast with previous results established for constant stopping times we allow arbitrary stopping times and randomized ones as well. There is no assumption about solvability of the the Isaacs equation in any sense (classical or viscosity). The zeroth-order “coefficient” and the “free” term are only assumed to be measurable in the space variable. We also prove that value functions are uniquely determined by the functions defining the corresponding Isaacs equations and thus stochastic games with the same Isaacs equation have the same value functions.
HAWC: A next-generation all-sky gamma-ray telescope

Abstract The High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory is currently under construction 4100 m above sea level on the slope of Pico de Orizaba in Mexico. HAWC is a high-duty cycle, large field-of-view instrument capable of monitoring the gamma-ray sky between roughly 50 GeV and 100 TeV. The detector will be used to record both steady and transient gamma-ray sources and to provide an unbiased survey of the northern sky with 2 π sr daily coverage. Upon completion in 2014, HAWC will comprise 300 large light-tight water tanks arrayed over an area of 20,000 m 2 . Each tank will be instrumented with four photomultipliers to detect particles from extensive air showers produced by gamma rays and cosmic rays. With 15 times the sensitivity of its predecessor experiment Milagro, the HAWC Observatory will enable significant detection of Crab-like fluxes each day at a median energy of 1 TeV. We present the scientific case for HAWC and describe its design and sensitivity.
Family structure, economic status, and educational attainment

"This study examines the effect of family structure on high school graduation by race and gender using data from the first twenty-one waves of the [U.S.] Panel Study of Income Dynamics and recently available retrospective marital histories.... The analysis tests the hypothesis that the negative effect on educational attainment often associated with living in a mother-only or stepfather family stems primarily from the reduced level of economic resources available to these households. Empirical findings indicate that living with a widowed, divorced, or separated mother has little or no effect on educational attainment once we control for economic status. However, living in a stepfather family appears to have a persistent negative effect on high school graduation rates."
A hybrid analog-digital differential analyzer system

In recent years, considerable effort has been expended toward combining the capabilities of digital and analog elements in specialized computing systems. The concept of blending analog and digital elements can be extended to a system of true hybrid computing elements.
Interpretation of quasielastic scattering spectra of probe species in complex fluids.

The objective of this paper is to correct an error in analyses of quasielastic scattering spectra. The error invokes a valid calculation under conditions in which its primary assumptions are incorrect, which results in misleading interpretations of spectra. Quasielastic scattering from dilute probes yields the incoherent structure factor g(1s)(q, t) = ⟨exp (iqΔx(t))⟩, with q being the magnitude of the scattering vector q and Δx(t) being the probe displacement parallel to q during a time interval t. The error is a claim that g(1s)(q, t) ∼ exp (−q2⟨(Δx(t))2⟩/2) for probes in an arbitrary solution, leading to the incorrect belief that ⟨(Δx(t))2⟩ of probes in complex fluids can be inferred from quasielastic scattering. The actual theoretical result refers only to monodisperse probes in simple Newtonian liquids. In general, g(1s)(q, t) is determined by all even moments ⟨(Δx(t))2n⟩, n = 1, 2, 3, … of the displacement distribution function P(Δx, t). Correspondingly, ⟨(Δx(t))2⟩ cannot in general be inferred from ...
Multivariable moment problems

In this paper we solve moment problems for Poisson transforms and, more generally, for completely positive linear maps on unital C*-algebras generated by “universal” row contractions associated with $$\mathbb{F}_{n}^{+}$$ , the free semigroup with n generators. This class of C*-algebras includes the Cuntz-Toeplitz algebra $$C^{*} (S_{1}, \ldots, S_{n})$$ (resp. $$C^{*} (B_{1}, \ldots, B_{n})$$ ) generated by the creation operators on the full (resp. symmetric, or anti-symmetric)) Fock space with n generators. As consequences, we obtain characterizations for the orbits of contractive Hilbert modules over complex free semigroup algebras such as $$\mathbb{CF}_{n}^{+}, \mathbb{C}[z_{1}, \ldots, z_{n}]$$ ,and, more generally, the quotient algebra $$\mathbb{CF}_{n}^{+}$$ , where J is an arbitrary two-sided ideal of $$\mathbb{CF}_{n}^{+}$$ . All these results are extended to the generalized Cuntz algebra $$\cal{O} (x_{i=1}^{n} G_{i}^{+})$$ , where G + are the positive cones ofdiscrete subgroups G + of the real line $$\mathbb{R}$$ . Moreover, we characterize the orbits of Hilbert modules over the quotient algebra $$\mathbb{C}_{i=1}^{*n} G_{i}^{+}/J$$ , where J is an arbitrary two-sided ideal ofthe free semigroup algebra $$\mathbb{C}_{i=1}^{*n} G_{i}^{+}$$ .
A subvortex technique for the close approach to a discretized vortex sheet

The close-approach problem associated with flow calculation methods based on vortex-lattice theory was examined numerically using two-dimensional discretized vortex sheets. The analysis first yields a near-field radius of approximately the distance apart of the vortices in the lattice; only within this distance from the sheet are the errors arising from the discretization significant. Various modifications to the discrete vortices are then considered with the objective of reducing the errors. This leads to a near-field model in which a vortex splits into an increasing number of subvortices as it is approached. The subvortices, whose strengths vary linearly from the vortex position, are evenly distributed along an interpolated curve passing through the basic vortices. This subvortex technique can be extended to the three-dimensional case and is efficient because the number of vortices is effectively increased, but only where and when needed.
Nonpoint pollution control: Inducing first-best outcomes through the use of threats

Abstract This paper develops an economic model to analyze the use of a policy that combines a voluntary approach to controlling nonpoint-source pollution with a background threat of an ambient tax if the voluntary approach is unsuccessful in meeting a pre-specified environmental goal. We show that such a policy can be designed to induce cost-minimizing abatement without actually imposing the tax because the threat of imposition of the tax is sufficient to induce voluntary compliance. Thus, the combined policy approach can not only be more effective in protecting environmental quality than a pure voluntary approach but can also be less costly than a pure ambient tax approach. However, whether the cost-minimizing choices are a unique equilibrium or not depends on the design of the tax policy and whether or not it can be applied retroactively. All results still hold if the background threat takes the form of a reducing in government subsidies.
Robust m-estimators

This paper provides a summary of the influence function approach to robust estimation of parametric models. Hampel's optimality results for M-estimators with a bounded influence function is generalized to allow for arbitrary choices of the asymptotic efficiency criterion and the norm of the influence function. Further extensions to other cases of practical interest are also considered.
X-Ray Lines from Hot Flows around White Dwarfs: Application to SS Cygni

Rather than accreting via a disk, some white dwarfs (WDs) in quiescent dwarf novae (DN) could accrete via an advection-dominated accretion flow (ADAF) possibly responsible for the X-ray bremsstrahlung emission observed. Such a hot accretion flow is also expected to produce characteristic thermal line emission. Using SS Cyg as a specific example, we show that knowing a priori the inclination and the WD mass in quiescent DN makes X-ray line diagnostics powerful probes of the flow structure in these systems. Current X-ray instruments can discriminate, from their width, between lines emitted from a flow with a Keplerian rotation rate and those emitted at a substantially sub-Keplerian rate. This could be used to observationally test the property of energy advection, which is at the origin of the partial radial pressure support by the hot gas and the sub-Keplerian rotation rate in an ADAF.
Water Oxidation by λ-MnO2: Catalysis by the Cubical Mn4O4 Subcluster Obtained by Delithiation of Spinel LiMn2O4

Nanocrystalline spinel LiMn(2)O(4) has been prepared and treatment of LiMn(2)O(4) with dilute nitric acid solution resulted in the delithiation of the framework, while maintaining the spinel structure, lambda-MnO(2). LiMn(2)O(4) is not a catalyst for water oxidation. Upon removal of the lithium, the cubical Mn(4)O(4) cores become active sites for oxidizing water to molecular oxygen, which was investigated with the photochemical [Ru(2+)(2,2'-bpy)(3)]/persulfate system at pH 5.8. The nanosize lambda-MnO(2) obtained from the nanocrystalline LiMn(2)O(4), which was synthesized by the citrate route, shows a significantly higher water oxidation catalytic activity (Turnover Frequency: 3 x 10(-5) mol O(2)/s/mol Mn) than that obtained via solid state reaction with micrometer and irregular particle sizes (Turnover Frequency: 5 x 10(-6) mol O(2)/s/mol Mn).
A 2 to 4 nm high power FEL on the SLAC linac

Abstract We report the results of preliminary studies of a 2 to 4 nm SASE FEL, using a photoinjector to produce the electron beam, and the SLAC linac to accelerate it to an energy up to 10 GeV. Longitudinal bunch compression is used to increase ten fold the peak current to 2.5 kA, while reducing the bunch length to the subpicosecond range. The saturated output power is in the multi-gigawatt range, producing about 1014 coherent photons within a bandwidth of about 0.2% rms, in a pulse of several millijoules. At 120 Hz repetition rate the average power is about 1 W. The system is optimized for X-ray microscopy in the water window around 2 to 4 nm, and will permit imaging a biological sample in a single subpicosecond pulse.
Finite order implications of common priors in infinite models

Abstract Lipman [Lipman, B., 2003. Finite order implications of common priors, Econometrica, 71 (July), 1255–1267] shows that in a finite model, the common prior assumption has weak implications for finite orders of beliefs about beliefs. In particular, the only such implications are those stemming from the weaker assumption of a common support. To explore the role of the finite model assumption in generating this conclusion, this paper considers the finite order implications of common priors in the simplest possible infinite model, namely, a countable model. I show that in countable models, the common prior assumption also implies a tail consistency condition regarding beliefs. More specifically, I show that in a countable model, the finite order implications of the common prior assumption are the same as those stemming from the assumption that priors have a common support and have tail probabilities converging to zero at the same rate.
Chemistry with [18F]Fluoride Ion

The success of molecular imaging with positron-emission tomography (PET) depends on the availability of selective molecular probes labeled with positron-emitters, such asfluorine-18 (t1/2 = 109.7 min). No-carrier-added (NCA) [18F]fluoride ion (18F–) is the primary reagent for the preparation of 18F-labeled tracers in high specific activity. In this microreview, we survey current and advancing radiochemical methods and technologies for the use of NCA [18F]fluoride ion in the preparation of 18F-labeled radiotracers for applications with PET. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
On-Demand Conflict Resolution Procedures for Air-Traffic Intersections

This paper develops a provably safe on-demand conflict resolution procedure (CRP) for intersecting routes in en route air-traffic control (ATC). Recent works have developed provably safe CRPs, which solve the conflict resolution for intersecting routes in a local manner that leads to decoupling of CRPs for different intersections. However, such a CRP is inefficient because it is always on, i.e., even in the absence of conflicts. This always-on CRP (even without conflicts) leads to unwanted CRP maneuvers resulting in increased travel time, travel distance, and required fuel. This paper removes the inefficiency of always-on CRPs by developing provably safe CRPs that can be activated on demand (when conflicts appear) to accommodate an impending conflict. Conditions are developed to guarantee safety during activation and deactivation of the CRP and the proposed on-demand approach is illustrated through an example route intersection.
Mild Palladium-Catalyzed C–H Alkylation Using Potassium Alkyltrifluoroborates in Combination with MnF3

A Pd-catalyzed method for ligand-directed C–H alkylation with organoboron reagents is described. The combination of potassium organotrifluoroborates, MnF3, and a PdII catalyst effects pyridine and amide-directed C–H alkylation. These reactions proceed under mild conditions (25–40 °C in weakly acidic media), are effective for installing methyl and 1° alkyl groups, and do not require promoters such as benzoquinone.
Correlation robust stochastic optimization

We consider a robust model proposed by Scarf, 1958, for stochastic optimization when only the marginal probabilities of (binary) random variables are given, and the correlation between the random variables is unknown. In the robust model, the objective is to minimize expected cost against worst possible joint distribution with those marginals. We introduce the concept of correlation gap to compare this model to the stochastic optimization model that ignores correlations and minimizes expected cost under independent Bernoulli distribution. We identify a class of functions, using concepts of summable cost sharing schemes from game theory, for which the correlation gap is well-bounded and the robust model can be approximated closely by the independent distribution model. As a result, we derive efficient approximation factors for many popular cost functions, like submodular functions, facility location, and Steiner tree. As a byproduct, our analysis also yields some new results in the areas of social welfare maximization and existence of Walrasian equilibria, which may be of independent interest.
Multi-input multi-output automatic design synthesis for performance and robustness

A direct-design method for solving the problem of robustness to cross-coupling perturbations in multivariable control systems is presented. The method uses numerical optimization procedures to manipulate the system feedback gains as direct design variables. The manipulation is accomplished in a manner that produces desired performance by pole placement and robustness by modification of the minimum singular values of the system return difference matrix. Channels affected by cross-coupling perturbation may be recognized by the character of their transfer function plots. The mechanism used by the pole placement and robustness routine in obtaining a robust design is evident from the gain changes associated with the Bode diagrams and the zero shifts shown on pole-zero plots. The pole placement and robustness routine uses gain equalization and zero assignment to modify the characteristics of the system in the design. A modification of the pole placement and robustness routine that may be applied to the design of robust observers is also presented. Using feedback and filter gains as direct design variables, a practical design procedure for robustness recovery in observer-based systems is obtained.
QUASI-ISOMETRIES, BOUNDARIES AND JSJ-DECOMPOSITIONS OF RELATIVELY HYPERBOLIC GROUPS

We demonstrate the quasi-isometry invariance of two important geometric structures for relatively hyperbolic groups: the coned space and the cusped space. As applications, we produce a JSJ-decomposition for relatively hyperbolic groups which is invariant under quasi-isometries and outer automorphisms, as well as a related splitting of the quasi-isometry groups of relatively hyperbolic groups.
One view of the future of industrial control

Abstract The current popular way of considering industrial control systems involves dividing their functional tasks among a four-level hierarchy. A further consolidation into two major areas results in the two comprising what is popularly called distributed control. The upper two levels then add the necessary additional functions to consider the overall control system as computer integrated manufacturing or CIM. The major needs in distributed control are for standards to promote interchangeability and a major increase in computational power at the supervisory level, Level 2. The major need in computer integrated manufacturing is for a methodology to coordinate and assure complete and accurate consideration of the massive amounts of information involved in the design and implementation of any such system.
DEOXYPSEUDOPHRYNAMINOL : A NOVEL ANTIBACTERIAL ALKALOID

Abstract Deoxypseudophrynaminol, 1 , is a potent antibacterial agent that inhibits the in vitro growth of vancomycin-resistant Enterococci and methicillin-resistant Staphylococcus aureus with MIC values ⩽40 μg/mL.
Heavy quark decays

Heavy quark decays are central to the international effort to test the Standard Model, and the b quark has emerged as the focus of this program. Studies of the b quark include detailed investigations of semileptonic and hadronic decays, as well as increasingly sensitive measurements of rare decays. With major new b-physics initiatives getting under way at nearly all high energy physics labs, the prospects for definitive tests of the Standard Model, or the discovery of physics beyond it, are excellent. Flavor physics is interesting because the weak eigenstates of the quarks are mixtures of the mass eigenstates. With three generations, the mixing is described by the Cabibbo-Kobayashi-Maskawa matrix [1] (Fig. 1).
Air density 2.7 billion years ago limited to less than twice modern levels by fossil raindrop imprints

Experiments dropping raindrops onto ash combined with raindrop fossil imprints yield an upper limit for air density in the Archaean. About 2.7 billion years ago, towards the end of the Archaean period, a rain shower left its mark on ash deposits from a volcanic eruption in what is now the South African veldt. As the ash hardened to form tuff rock, the crater-like imprints of the individual raindrops were fossilized. An analysis of these imprints, aided by comparison with similar prints formed during the 2010 Eyjafjallajokull eruption in Iceland, suggests that air density during the Archaean was no more than twice modern levels. At that time, the Sun was dimmer than it is today, but the climate was warm. Most theories to explain this 'Faint Young Sun' paradox have assumed that the atmosphere was denser in the Archaean than it is now, and that the greenhouse effect was stronger, but this latest work seems to rule out higher carbon dioxide levels; nitrogen-pressure broadening remains unlikely, but possible. According to the ‘Faint Young Sun’ paradox, during the late Archaean eon a Sun approximately 20% dimmer warmed the early Earth such that it had liquid water and a clement climate1. Explanations for this phenomenon have invoked a denser atmosphere that provided warmth by nitrogen pressure broadening1 or enhanced greenhouse gas concentrations2. Such solutions are allowed by geochemical studies and numerical investigations that place approximate concentration limits on Archaean atmospheric gases, including methane, carbon dioxide and oxygen2,3,4,5,6,7. But no field data constraining ground-level air density and barometric pressure have been reported, leaving the plausibility of these various hypotheses in doubt. Here we show that raindrop imprints in tuffs of the Ventersdorp Supergroup, South Africa, constrain surface air density 2.7 billion years ago to less than twice modern levels. We interpret the raindrop fossils using experiments in which water droplets of known size fall at terminal velocity into fresh and weathered volcanic ash, thus defining a relationship between imprint size and raindrop impact momentum. Fragmentation following raindrop flattening limits raindrop size to a maximum value independent of air density, whereas raindrop terminal velocity varies as the inverse of the square root of air density. If the Archaean raindrops reached the modern maximum measured size, air density must have been less than 2.3 kg m−3, compared to today’s 1.2 kg m−3, but because such drops rarely occur, air density was more probably below 1.3 kg m−3. The upper estimate for air density renders the pressure broadening explanation1 possible, but it is improbable under the likely lower estimates. Our results also disallow the extreme CO2 levels required for hot Archaean climates8.
On the symmetric enveloping algebra of planar algebra subfactors

We give a diagrammatic description of Popa's symmetric enveloping algebras associated to planar algebra subfactors. As an application we construct a natural family of derivations on these factors and compute a certain free entropy dimension type quantity. © 2013 American Mathematical Society.
UCLA Parallel PIC Framework

Abstract The UCLA Parallel PIC Framework (UPIC) has been developed to provide trusted components for the rapid construction of new, parallel Particle-in-Cell (PIC) codes. The Framework uses object-based ideas in Fortran95, and is designed to provide support for various kinds of PIC codes on various kinds of hardware. The focus is on student programmers. The Framework supports multiple numerical methods, different physics approximations, different numerical optimizations and implementations for different hardware. It is designed with “defensive” programming in mind, meaning that it contains many error checks and debugging helps. Above all, it is designed to hide the complexity of parallel processing. It is currently being used in a number of new Parallel PIC codes.
A model for a generalized data access method

The proliferation of the methods used in modern operating systems to access data is apparent. In the operating system OS/360 alone there exist multiple ways of accessing sequential data (BSAM, QSAM, BPAM), indexed sequential data (BISAM, QISAM) and directly addressable data (BDAM). If one adds to this the variations of the above used by various systems that run under the control of OS/360, such as IBM's data base management system IMS/360, there exists almost a countless number of ways to access and store data within a computer system.
Beryllium in the ultra-lithium-deficient, metal-poor halo DWARF G186-26

The vast majority of low-metal halo dwarfs show a similar amount of Li; this has been attributed to the Li that was produced in the big bang. However, there are nine known halo stars with T > 5900 K and [Fe/H] < -1.0 that are ultra-Li-deficient. We have looked for Be in the very low metallicity star G186-26, at [Fe/H] = -2.71, which is one of the ultra-Li-deficient stars. This star is also ultra-Be-deficient. Relative to Be in the Li-normal stars at [Fe/H] = -2.7, G186-26 is down in Be by more than 0.8 dex. Of two potential causes for the Li deficiency—mass transfer in a pre-blue straggler or extra rotationally induced mixing in a star that was initially a very rapid rotator—the absence of Be favors the blue straggler hypothesis, but the rotation model cannot be ruled out completely.
The Stereoselective Aldol Condensation of α-Fluoroacetates

Abstract 2,6-Di-t-butyl-4-methylphenyl(BHT) and benzyl α-fluoroacetates were converted to their lithium enolates and were utilized in the aldol condensation. The improved diastereoselectivity found with the BHT esters is thought to arise from of equilibration of the aldol product rather than stereoselective enolate formation.
Thou Shalt Not Clone One Bit

We prove a no-triplets theorem for spin 1 particles, which implies a strengthened form of the no-cloning theorem.
SPECTRAL LAGS AND THE LAG-LUMINOSITY RELATION: AN INVESTIGATION WITH SWIFT BAT GAMMA-RAY BURSTS

Spectral lag, the time difference between the arrival of high-energy and low-energy photons, is a common feature in gamma-ray bursts (GRBs). Norris et al. reported a correlation between the spectral lag and the isotropic peak luminosity of GRBs based on a limited sample. More recently, a number of authors have provided further support for this correlation using arbitrary energy bands of various instruments. In this paper, we report on a systematic extraction of spectral lags based on the largest Swift sample to date of 31 GRBs with measured redshifts. We extracted the spectral lags for all combinations of the standard Swift hard X-ray energy bands: 15-25 keV, 25-50 keV, 50-100 keV, and 100-200 keV and plotted the time dilation corrected lag as a function of isotropic peak luminosity. The mean value of the correlation coefficient for various channel combinations is -0.68 with a chance probability of {approx}0.7 x 10{sup -3}. In addition, the mean value of the power-law index is 1.4 +- 0.3. Hence, our study lends support to the existence of a lag-luminosity correlation, albeit with large scatter.
Competitive shocks and industrial structure: the case of Polish manufacturing

Abstract A large number of countries have recently experienced competitive shocks: sudden increases in the role that market forces play in determining the evolution of various industries. In this paper, we study the implications of Poland's competitive shock for three elements of the structure of that country's manufacturing sector: entry, concentration, and foreign presence. Our analysis underlines the importance of explicitly identifying the specific distortions built into initial (pre-shock) industrial structure and lags in their adjustment to more competitive conditions.
COMMENTS ON GREEN–ZHOU “MONEY AS A MECHANISM IN A BEWLEY ECONOMY”*

This article discusses the paper by Green and Zhou “Money as a Mechanism in a Bewley Economy” as presented at the second Karaken Conference.
Modern cross-linking strategies for synthesizing acellular hemoglobin-based oxygen carriers.

Unmodified cell-free hemoglobin (Hb) is structurally unstable when transfused into the blood stream (Valeri et al., Artif Cells Blood Substit Immobil Biotechnol. 2000;28:451-475; Chan et al., Toxicol Pathol. 2000;28:635-642; Eike, Dissertation, 2005; Eike and Palmer, Biotechnol Prog. 2004;20:946-952). This review examines some of the latest chemical strategies used over the last 5 years to intra- and intermolecularly cross-link Hb, thereby stabilizing its quaternary structure. Therefore, this work will address the following aspects: (1) site-specific chemical modifications of Hb and (2) non-site-specific chemical modifications of Hb, including, but not limited to, PolyHeme®, Hemopure®, Oxyglobin®, and SOD-Hb. Current strategies for synthesizing PEGylated Hb is outside the scope of this review and will not be discussed herein. For a more thorough review of PEGylated Hb, the reader is directed to the following works: Cabrales and Friedman, Transfus Alternatives in Transfus Med. 2007;9:281–293 and Winslow, Biochim Biophys Acta, 2008;1784(10):1382–1386.
Heat of formation of Benzophenone Oxide

The heat of formation of benzophenone oxide, Ph2CO2, was measured using photoacoustic calorimetry. The enthalpy of the reaction Ph2CN2 + O2 Ph2CO2 + N2 was found to be −48.0 ±0.8 kcal mol−1 and ΔHf(Ph2CN2) was determined by measuring the reaction enthalpy for Ph2CN2 + EtOH Ph2CHOEt + N2 (−53.6 ±1.0 kcal mol−1). Taking ΔHf(PhCHOEt) = −10.6 kcal mol−1 led to ΔHf(Ph2CN2) = 99.2 ± 1.5 kcal mol−1 and hence to ΔHf(Ph2CO2) = 51.1 ± 2.0 kcal mol−1. The results imply that the self-reaction of benzophenone oxide i.e., 2Ph2CO2 2Ph2CO + O2 is exothermic by −76.0 ±4.0 kcal mol−1.
The Chromospheric Activity and Ages of M Dwarf Stars in Wide Binary Systems

We investigate the relationship between age and chromospheric activity for 139 M dwarf stars in wide binary systems with white dwarf companions. The age of each system is determined from the cooling age of its white dwarf component. The current limit for activity-age relations found for M dwarfs in open clusters is 4 Gyr. Our unique approach to finding ages for M stars allows for the exploration of this relationship at ages older than 4 Gyr. The general trend of stars remaining active for a longer time at a later spectral type is confirmed. However, our larger sample and greater age range reveal additional complexity in assigning age based on activity alone. We find that M dwarfs in wide binaries older than 4 Gyr depart from the loglinear relation for clusters and are found to have activity at magnitudes, colors, and masses that are brighter, bluer, and more massive than predicted by the cluster relation. In addition to our activity-age results, we present the measured radial velocities and complete space motions for 161 white dwarf stars in wide binaries.
Stabilization of max-min fair networks without per-flow state

Let a flow be a sequence of packets that are sent from a source computer to a destination computer. In this paper, we consider the fair allocation of bandwidth to each flow in a computer network. We focus on max?min fairness, which assigns to each flow the largest possible bandwidth that avoids affecting other flows. What distinguishes our approach is that routers only maintain a constant amount of state, i.e., no per-flow state is maintained. This is consistent with trends in the Internet (such as the proposed Differentiated Services Internet architecture). In addition, to provide a high degree of fault-tolerance, we ensure our approach is self-stabilizing, that is, it returns to a normal operating state after a finite sequence of faults.
Remote Sensing of Biomass Burning in the Tropics

Biomass burning in the tropics, a large source of trace gases, has expanded drastically in the last decade due to increase in the controlled and uncontrolled deforestation in South America (Setzer et al. 1988; Malingreau and Tucker 1988), and due to an increase in the area of cultivated land with the expansion of population in Africa and South America (Seiler and Crutzen 1980; Houghton et al. 1987). In the burning process trace gases and particulates are emitted to the atmosphere, and the ability of the earth to fix CO2 is substantially reduced (17% of the primary productivity occurs in the humid tropical forests — Atjay et al. 1979; Mooney et al. 1987), and as a result has a strong contribution to the anticipated climate change (Houghton and Woodwell 1989).
Diffuse fluxes of cosmic high-energy neutrinos

Production spectra of high-energy neutrinos from galactic cosmic-ray interactions with interstellar gas and extragalactic ultrahigh-energy cosmic-ray interactions with microwave blackbody photons are presented and discussed. These production processes involve the decay of charged pions and are thus related to the production of cosmic gamma rays from the decay of neutral pions. Estimates of the neutrino fluxes from various diffuse cosmic sources are then made, and the reasons for significant differences with previous estimates are discussed. Small predicted event rates for a DUMAND (deep underwater muon and neutrino detector) type detection system, combined with a possible significant flux of prompt neutrinos from the atmosphere above 50 TeV, may make the study of diffuse extraterrestrial neutrinos more difficult than previously thought.
On maximal injective subalgebras of tensor products of von Neumann algebras

Abstract Let M i be a von Neumann algebra, and B i be a maximal injective von Neumann subalgebra of M i , i = 1 , 2 . If M 1 has separable predual and the center of B 1 is atomic, e.g., B 1 is a factor, then B 1 ⊗ ¯ B 2 is a maximal injective von Neumann subalgebra of M 1 ⊗ ¯ M 2 . This partly answers a question of Popa.
A sigma-delta modulation based BIST scheme for mixed-signal circuits

In this work, we present the analysis of a built-in self-test (BIST) scheme for mixed-signal circuits that is intended to provide on-chip stimulus generation and response analysis. Based on the sigma-delta modulation principle, the proposed scheme can produce high-quality stimuli and obtain accurate measurements without the need of precise analog circuitry. Numerical simulations are conducted to validate our idea and the results show that the scheme is a promising BIST approach for mixed-signal circuits.
Diamagnetism of graphite

A calculation of the diamagnetism of graphite including the effects of trigonal warping of the Fermi surfaces has been performed using Fukuyama's formulation of the diamagnetism of Bloch electrons. Inclusion of the trigonal warping increases the diamagnetism by about 13% at low temperatures and reduces it by about 1% at high temperatures. A paramagnetic constant is used to represent all effects not associated with the free carriers. The experimental diamagnetism can be fitted quite well using values of the energy band parameters which give agreement with the de Haas-van Alphen effect, optical absorption, and magnetoreflection experiments.
Assessing the Academic Networked Environment

Le projet CNI (Coalition for Networked Information) a rassemble sept institutions de l'enseignement superieur pour partager leurs experiences sur l'evaluation de l'impact des ressources et des services electroniques. L'article rapporte les efforts fournis dans quatre de ces etablissements a partir d'etudes realises aupres des utilisateurs, et les resultats obtenus : l'Universite de Washington, Virginia Tech, Gettysburg College et King's College a Londres.
A Caveat for Single-Molecule Magnetism: Non-linear Arrhenius Plots

Single-molecule magnets (SMMs) are molecules that, below a certain temperature (TB), function as individual nanoscale magnetic particles, exhibiting magnetization hysteresis loops. As such, they represent an alternative and molecular (bottom-up) route to nanomagnetism, complementing the top-down approach to traditional magnetic nanomaterials. SMMs also exhibit fascinating quantum behavior such as quantum tunneling of the magnetization (QTM) and quantum phase interference (QPI), showing that they are truly mesoscale entities straddling the classical/quantum divide. The barrier causing slow magnetization relaxation arises from a combination of a large ground-state spin (S) and easy-axis anisotropy (negative zerofield splitting parameter, D). The most studied SMMs are the [Mn12O12 ACHTUNGTRENNUNG(O2CR)16 ACHTUNGTRENNUNG(H2O)4] family with S=10 ground states, and their derivatives, while in recent years others have been discovered. Alternating current (ac) magnetic susceptibility studies are a convenient method of assessing whether a compound might be an SMM; frequency-dependent out-of-phase (c’’M) signals are indicative of the superparamagnet-like properties of an SMM. The variation in signal position with ac frequency can then be used as a source of rate vs T kinetic data, because the c’’M peak maximum is the temperature at which the angular frequency of the oscillating field equals the rate (1/t, where t is the relaxation lifetime) of spin vector reversal. This allows construction of a ln ACHTUNGTRENNUNG(1/t) vs 1/T plot based on the Arrhenius relationship given in Equation (1), the behavior expected of a thermally-activated process over a single barrier :
Sexual dysfunction in the patient with prostatitis

Prostatitis (chronic prostatitis/chronic pelvic pain syndrome ) is a common condition in men that accounts for a significant number of visits to a medical doctor or urologist. It is one of the most widely diagnosed conditions in men who attend urologic clinics. Erectile dysfunction, defined as the consistent inability to obtain and/or maintain a penile erection sufficient for adequate sexual relations, also is a common problem. This review explores the links between sexual dysfunction and prostatitis. Most of the data linking lower urinary tract symptoms and erectile dysfunction suggest that lower urinary tract symptoms impair the overall quality of life and that a low quality of life contributes to or causes erectile dysfunction. Prostatitis-like symptoms such as perineal, penile, and suprapubic discomfort or pain during or after ejaculation and voiding complaints such as irritative and obstructive voiding symptoms (urinary frequency, urgency, and dysuria) may affect the global emotional well-being of a man. Erectile dysfunction also is strongly associated with a negative impact on the quality of life. The available literature demonstrating the influence of CP/CPPS on the incidence of erectile dysfunction is scant. From the literature, it is known that lower urinary tract symptoms and benign prostatic hyperplasia are definitely related to erectile dysfunction. Any kind of pain is likely to be the most significant symptom in men with CP/CPPS as it relates to sexual dysfunction. Sexual dysfunction such as ejaculation discomfort is described as a symptom of CP/CPPS. Most of the data linking the two suggest that CP/CPPS impairs the overall quality of life and it is this that contributes to or causes erectile dysfunction.
Total asymmetric synthesis of highly constrained amino acids β-isopropyl-2',6'-dimethyl-tyrosines

Abstract All four stereoisomers of the highly constrained aromatic α-amino acid β-isopropyl-2′,6′-dimethyltyrosine have been asymmetrically synthesized on a large scale. A catalytic asymmetric Michael addition of an organocuprate to a chiral α,β-unsaturated acyloxazolidinone and subsequent direct or indirect stereoselective electrophilic azidation of the α-position of the resulting product was followed by hydrolysis, hydrogenation and finally deprotection of the phenol group to afford the desired amino acids. The reactions generally proceeded in good stereoselectivitities (75–95% ee/de) and yields (70–90%), making these optically pure amino acids available in large scale practical for the synthesis of peptides and other studies.
Geometry of canonical bases and mirror symmetry

A decorated surface S is an oriented surface with boundary and a finite, possibly empty, set of special points on the boundary, considered modulo isotopy. Let G be a split reductive group over Q. A pair (G, S) gives rise to a moduli spaceAG,S , closely related to the moduli space of G-local systems on S. It is equipped with a positive structure (Fock and Goncharov, Publ Math IHES 103:1–212, 2006). So a set AG,S(Z ) of its integral tropical points is defined. We introduce a rational positive function W on the space AG,S , called the potential. Its tropicalisation is a function W t : AG,S(Z ) → Z. The condition W t ≥ 0 defines a subset of positive integral tropical points AG,S(Zt ). For G = SL2, we recover the set of positive integralA-laminations on S from Fock and Goncharov (Publ Math IHES 103:1–212, 2006). We prove that when S is a disc with n special points on the boundary, the set AG,S(Zt ) parametrises top dimensional components of the fibers of the convolution maps. Therefore, via the geometric Satake correspondence (Lusztig, Asterisque 101–102:208– 229, 1983; Ginzburg,1995; Mirkovic and Vilonen, Ann Math (2) 166(1):95– 143, 2007; Beilinson and Drinfeld, Chiral algebras. American Mathematical Society Colloquium Publications, vol. 51, 2004) they provide a canonical basis in the tensor product invariants of irreducible modules of the Langlands dual group GL : (Vλ1 ⊗ . . .⊗ Vλn )G L . (1) A. Goncharov (B) · L. Shen Mathematics Department, Yale University, New Haven, CT 06520, USA e-mail: alexander.goncharov@yale.edu
Nonlinear Bound States on Weakly Homogeneous Spaces

We prove the existence of ground state solutions for a class of nonlinear elliptic equations, arising in the production of standing wave solutions to an associated family of nonlinear Schrodinger equations. We examine two constrained minimization problems, which give rise to such solutions. One yields what we call F λ-minimizers, the other energy minimizers. We produce such ground state solutions on a class of Riemannian manifolds called weakly homogeneous spaces, and establish smoothness, positivity, and decay properties. We also identify classes of Riemannian manifolds with no such minimizers, and classes for which essential uniqueness of positive solutions to the associated elliptic PDE fails.
Cosmological Neutrino Signatures for Grand Unification Scale Physics

Abstract Physics beyond the standard model might imply the cosmological production of particles with grand unification scale energies. Nucleons and γ-rays from such processes are candidates for the cosmic rays observed beyond 100 EeV (10 20 eV). Using a new particle propagation code, we calculate the neutrino fluxes predicted by such scenarios if consistency with the observed cosmic ray flux and the universal γ-ray background at 1–10 GeV is required. Flux levels detectable by proposed km 3 scale neutrino observatories are allowed by these constraints. Bounds on or detection of a neutrino flux above ∼ 1 EeV would allow neutrino astronomy to probe grand unification scale physics.