cssi/SciSciGPT-SciSciNet huggingface dataset:
The PAMELA Positron Excess from Annihilations into a Light Boson

Recently published results from the PAMELA experiment have shown conclusive evidence for an excess of positrons at high ( ~ 10–100 GeV) energies, confirming earlier indications from HEAT and AMS-01. Such a signal is generally expected from dark matter annihilations. However, the hard positron spectrum and large amplitude are difficult to achieve in most conventional WIMP models. The absence of any associated excess in anti-protons is highly constraining on models with hadronic annihilation modes. We revisit an earlier proposal, wherein the dark matter annihilates into a new light (GeV) boson , which is kinematically constrained to go to hard leptonic states, without anti-protons or π0's. We find this provides a very good fit to the data. The light boson naturally provides a mechanism by which large cross sections can be achieved through the Sommerfeld enhancement, as was recently proposed. Depending on the mass of the WIMP, the rise may continue above 300 GeV, the extent of PAMELA's ability to discriminate between electrons and positrons.
Quantum Tunneling between Paramagnetic and Superconducting States of a Nanometer-Scale Superconducting Grain Placed in a Magnetic Field

We consider the process of quantum tunneling between the superconducting and paramagnetic states of a nanometer-scale superconducting grain placed in a magnetic field. The grain is supposed to be weakly coupled to a normal metallic contact that plays the role of the spin reservoir. Using the instanton method, we find the probability of the quantum tunneling process and express it in terms of the applied magnetic field, order parameter of the superconducting grain, and conductance of the tunneling junction between the grain and metallic contact.
Buoyancy Instabilities in Weakly Magnetized Low-Collisionality Plasmas

I calculate the linear stability of a stratified low-collisionality plasma in the presence of a weak magnetic field. Heat is assumed to flow only along magnetic field lines. In the absence of a heat flux in the background plasma, Balbus demonstrated that plasmas in which the temperature increases in the direction of gravity are buoyantly unstable to convective-like motions (the "magnetothermal instability"). I show that in the presence of a background heat flux, an analogous instability is present when the temperature decreases in the direction of gravity. The instability is driven by the background heat flux, and the fastest growing mode has a growth time of order the local dynamical time. Thus, independent of the sign of the temperature gradient, weakly magnetized low-collisionality plasmas are unstable on a dynamical time to magnetically mediated buoyancy instabilities. The instability described in this paper is predicted to be present in clusters of galaxies at radii ~0.1-100 kpc, where the observed temperature increases outward. Possible consequences for the origin of cluster magnetic fields, "cooling flows," and the thermodynamics of the intercluster medium are briefly discussed.
Nitration of Polycyclic Aromatic Hydrocarbons Using a Supported Catalyst

Abstract We report the use of catalyst, sulfuric acid supported on silica-gel, as promising method for facile, high yielding, regioselective syntheses of mononitrated polycyclic aromatic hydrocarbons, 6-nitrochrysene, 1-nitropyrene, 1-nitronaphthalene, 2-nitrofluorene, 3-nitrofluoranthene, and 9-nitroanthracene.
Nonperturbative theory of weak pre- and post-selected measurements

Abstract This paper starts with a brief review of the topic of strong and weak pre- and post-selected (PPS) quantum measurements, as well as weak values, and afterwards presents original work. In particular, we develop a nonperturbative theory of weak PPS measurements of an arbitrary system with an arbitrary meter, for arbitrary initial states of the system and the meter. New and simple analytical formulas are obtained for the average and the distribution of the meter pointer variable. These formulas hold to all orders in the weak value. In the case of a mixed preselected state, in addition to the standard weak value, an associated weak value is required to describe weak PPS measurements. In the linear regime, the theory provides the generalized Aharonov–Albert–Vaidman formula. Moreover, we reveal two new regimes of weak PPS measurements: the strongly-nonlinear regime and the inverted region (the regime with a very large weak value), where the system-dependent contribution to the pointer deflection decreases with increasing the measurement strength. The optimal conditions for weak PPS measurements are obtained in the strongly-nonlinear regime, where the magnitude of the average pointer deflection is equal or close to the maximum. This maximum is independent of the measurement strength, being typically of the order of the pointer uncertainty. In the optimal regime, the small parameter of the theory is comparable to the overlap of the pre- and post-selected states. We show that the amplification coefficient in the weak PPS measurements is generally a product of two qualitatively different factors. The effects of the free system and meter Hamiltonians are discussed. We also estimate the size of the ensemble required for a measurement and identify optimal and efficient meters for weak measurements. Exact solutions are obtained for a certain class of the measured observables. These solutions are used for numerical calculations, the results of which agree with the theory. Moreover, the theory is extended to allow for a completely general post-selection measurement. We also discuss time-symmetry properties of PPS measurements of any strength and the relation between PPS and standard (not post-selected) measurements.
New Roma rights legislation in Bosnia and Herzegovina: positive, negative or indifferent?

Abstract On 31 March 2003, the Parliament of Bosnia and Herzegovina passed minority rights legislation. This article reviews its main provisions and critically asks: To what extent does this law meet international and European standards? How effective will this law be in addressing the socio-economic and political crisis facing the Roma minority today? Apart from granting minority status to the Roma, a right they had enjoyed under the 1974 Yugoslav Constitution, this article concludes that the new law offers little by way of additional protections beyond those already available, albeit unutilised, under the Dayton Peace Agreement and the State and Entity Constitutions. It further notes that the limited nature of minority rights legislation to cultural, linguistic and religious rights means that it fails to address many of the critical issues facing the Roma today, such as illiteracy, poverty, widespread discrimination and prejudice, and political disenfranchisement.
The NOx and N2O Emission Characteristics of an HCCI Engine Operated With n-Heptane

This paper presents the oxides of nitrogen (NOx ) and nitrous oxide (N2 O) emission characteristics of a Cooperative Fuel Research (CFR) engine modified to operate in homogeneous charge compression ignition (HCCI) combustion mode. N-heptane was used as the fuel in this research. Several parameters were varied, including intake air temperature and pressure, air/fuel ratio (AFR), compression ratio (CR), and exhaust gas recirculation (EGR) rate, to alter the HCCI combustion phasing from an overly advanced condition where knocking occurred to an overly retarded condition where incomplete combustion occurred with excessive emissions of unburned hydrocarbons (UHC) and carbon monoxide (CO). NOx emissions below 5 ppm were obtained over a fairly wide range of operating conditions, except when knocking or incomplete combustion occurred. The NOx emissions were relatively constant when the combustion phasing was within the acceptable range. NOx emissions increased substantially when the HCCI combustion phasing was retarded beyond the optimal phasing even though lower combustion temperatures were expected. The increased N2 O and UHC emissions observed with retarded combustion phasing may contribute to this unexpected increase in NOx emissions. N2 O emissions were generally less than 0.5 ppm; however, they increased substantially with excessively retarded and incomplete combustion. The highest measured N2 O emissions were 1.7 ppm, which occurred when the combustion efficiency was approximately 70%.
Federal Coordination of Local Housing Demolition in the Presence of Filtering and Migration

Vacant housing and even housing demolition have recently become an issue in a number of countries. Given this renewed interest in demolition, this paper contributes to the literature on (i) housing demolition and (ii) policy coordination. The paper extends Sweeney’s (Econometrica 42:147–167, 1974a) analysis of demolition and filtering, by letting households also choose their location. Then when demolishing part of its housing stock, a city effectively evicts some of its residents not just out of the housing quality it demolishes but out of every other of its qualities, too. The paper shows that demolition’s coordination strengthens local governments’ incentive to demolish part of their stock, by shutting down inter city migration within qualities.—A case study on Germany’s East illustrates the effects of coordinated, simultaneous every-city demolition.
Structural Properties of Massive Young Clusters

We have retrieved multicolor WFPC2/Hubble Space Telescope data from the STScI archive for 27 nearby massive ( 3 × 104 M☉) young (< 20 Myr) star clusters (MYCs). The data represents the most complete sample of clearly resolved MYCs to date. We have analyzed their structural properties and have found that they can be classified as either super-star clusters (SSCs) or as scaled OB associations (SOBAs). SSCs have a compact core possibly surrounded by a halo while SOBAs have no core. A morphological sequence can be established from SSCs with weak halos to SSCs with strong halos to SOBAs, and we propose that this is linked to the original mass distribution of the parent giant molecular clouds. Our results indicate that a significant fraction of the stars in MYCs dissipate on timescales of 10 Gyr or less due to the extended character of some of the clusters. Also, SSCs with ages younger than 7 Myr have smaller cores on average than those with ages older than 7 Myr, confirming predictions of numerical simulations with mass loss.
Thermoelectric properties of the intermediate valent cerium intermetallic Ce2Ni3Si5 doped with Pd, Co, and Cu

Abstract The nickel site of Ce 2 Ni 3 Si 5 , which has the orthorhombic U 2 Co 3 Si 5 structure type, can be fully substituted with palladium and cobalt and partially substituted with copper. The volume of the lattice expands from 635 A 3 to 704 A 3 upon substitution with palladium while the volume contraction with cobalt and copper substitutions are much smaller. The thermopower of Ce 2 Ni 3 Si 5 is 32 μV/K at room temperature and increases to 60 μV/K at 40 K. This relatively high thermopower is decreased by substitution of the three metals studied here. The relatively temperature independent thermal conductivity of between 50 and 60 mW/Kcm for Ce 2 Ni 3 Si 5 is decreased in magnitude by substitution of the heavier palladium, especially at temperatures below 150 K, and is changed to typical metallic behavior by cobalt substitution. Upon cooling from room temperature, the electrical resistivity of Ce 2 Ni 3 Si 5 displays a broad plateau of 300 μΩcm until a precipitous drop below 120 K, indicative of coherence effects in the Kondo interactions between the cerium moments and conduction electrons. Copper and palladium substitutions result in a gradual reduction in the effects of cerium intermediate valence, whereas cobalt substitution drives the resistivity to metallic behavior but with a relatively large room temperature resistivity of 400 μΩcm.
Empire forestry and the origins of environmentalism

Abstract When and where did the environmental movement begin? To understand how a public endued with the principles of laissez-faire reversed in such short order a century-old policy of government land disposal, this paper examines how public ownership of land came to be celebrated, with a newly defined professional corps of government foresters such as Dietrich Brandis and Gifford Pinchot feted as popular heroes. Hard-headed environmentalists and legislators found in empire forestry a ready-made model to construct vast areas of the public domain as a utensil for not only environmental but state purposes—industrial, settlement, and budgetary. The empire forestry matrix of government reservations, fire protection, and revenue-enhancing forests solved the tension between romantic preservationist notions and laissez-faire ideals and gave the compromise from which modern environmentalism emerged: it posed environmental problems and solutions as a means to construct the state. This article traces the international trail of modern environmentalism from India, under Lord Dalhousie's forest charter, to the British colonies in Africa and Australasia where it matured, and finally to Canada, the United States and other parts of the globe where environmentalism permanently entered the pantheon of democratic political creeds.
“On water” sp3–sp2 cross-couplings between benzylic and alkenyl halides

Organic-solvent-free cross-couplings between benzylic and alkenyl halides have been developed. Various alkenyl halides can be efficiently benzylated by combining the precursor halides in the presence of Zn dust and a Pd catalyst at room temperature, in water as the only medium.
Structure and decay characteristics of turbulence in the near- and far-wake of a moderately loaded compressor rotor-blade

The wake of a turbomachinery rotor-blade is turbulent, highly three-dimensional, and nonisotropic with appreciable curvature in the trailing-edge and near-wake regions. The characteristics of the turbulence vary considerably with radius, blade loading, free-stream turbulence, Reynolds number, and the rotor-blade geometry. This paper is concerned with the turbulence properties of a moderately loaded compressor blade, particularly near the blade trailing-edge. The tangential variation of the axial, tangential and radial intensities and stresses across the wake, as well as their decay characteristics were measured with a tri-axial hot-wire probe in the rotor frame of reference. The decay of intensities and stresses were found to be very rapid in the trailing-edge and near-wake regions and slow in the far-wake region. The effects of inlet-guide-vane and the hub-wall boundary layers on the rotor wake turbulence spectra are also discussed. Similarity rules for the three components of intensity are also derived and presented in this paper.
A Solution-Phase Chemical Approach to a New Crystal Structure of Cobalt.

Kinetic control of crystal growth in the presence of a coordinating ligand is critical for the formation of a new structure of elemental cobalt (e-cobalt, the unit cell with the two different types of cobalt atoms is shown), which was discovered upon analyzing the metallic powder produced by the thermal decomposition of [Co2 (CO)8 ] in solution in the presence of trioctylphosphane oxide [TOPO, Eq. (1)].
Joint scheduling and resource allocation for multiple video decoding tasks

In this paper we propose a joint resource allocation and scheduling algorithm for video decoding on a resource-constrained system. By decomposing a multimedia task into decoding jobs using quality-driven priority classes, we demonstrate using queuing theoretic analysis that significant power savings can be achieved under small video quality degradation without requiring the encoder to adapt its transmitted bitstream. Based on this scheduling algorithm, we propose an algorithm for maximizing the sum of video qualities in a multiple task environment, while minimizing system energy consumption, without requiring tasks to reveal information about their performances to the system or to other potentially exploitative applications. Importantly, we offer a method to optimize the performance of multiple video decoding tasks on an energy-constrained system, while protecting private information about the system and the applications.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Molecular Federalism and the Structures of Private Lawmaking

This article explores "molecular federalism." Private lawmakers—ranging from familiar organizations like the American Law Institute and the New York Stock Exchange to less well known ones, like the International Chamber of Commerce and associations of banks—are here envisioned as part of a federalist scheme that operates at a "molecular" level rather than at the level of the state. The function and legitimacy of private lawmakers, and the strengths and weaknesses of private lawmaking, are assessed under the rubric of federalism. The article takes up both horizontal and vertical aspects of molecular federalism, considering the possibilities of competitive private lawmaking and the potential for (and limits of) governmental control. The article accounts for the extraterritoriality of private lawmaking and considers how private legislation may escape some of the vertical checks and balances associated with state-based federalism, not only through extraterritoriality, but also through some surprising shifts in the federalist hierarchy. The paper also explores how one legal regime can become dominant, while other contexts may suffer legal fragmentation. The paper attempts to place its analysis within the context of some prominent U.S. theorists of federalism, including Herbert Wechsler and Justice Brennan, and contemporary European theorists, such as Gunther Teubner. The conclusion is that molecular federalism, like its state-based counterpart, produces mixed results, and often in a way that accentuates both the strengths and the weaknesses of state-based federalism. The paper also suggests that a constitution for private lawmaking, or a similar system of meta-rules, may be necessary to allow private lawmaking to come closest to its potential.
Cultural Variation in the Theory of the Firm

This paper presents a model of the firm that includes the possibility of firm and employee on-the-job decision making based on alternatives to profit and utility maximization. Such alternatives are relevant and significant when explaining firm activity in cultural environments in which self-interest is not considered to be a primary force driving human behavior. Three types of firms are defined and their properties are compared: the Western firm, the Japanese firm, and the clan. The third is a combination of the first two.
Optimal delays in decision and control

Computations involved in controlling a system or a decision process are time-consuming in practice. The problem of optimally choosing the estimation and control delays is formulated in the dynamic programming framework and illustrated by examples. Selection of optimal estimation and control algorithms is outlined conceptually.
Facile synthesis of 5′-(N-acyl sulfonamide) derivatized nucleosides

Abstract The acylation of several primary sulfonamides with N6-benzoyl-2′,3′-isopropylidene-5′-carboxylic acid-5′-deoxyadenosine ( 1 ) is described. Literature methods for the construction of the N-acyl sulfonamide functionality proved ineffective for synthesizing 5′-N-acyl sulfonamide derivatives of 1 . The combination of DCC/DMAP provided the mild conditions necessary to effect coupling of the protected nucleoside acid with various primary sulfonamides in good to high yield.
Integration of Graph Theory and Quantum Chemistry for Structure-Activity Relationships

Abstract The objective of this article is to outline both graph-theoretically based and quantum chemically based structural indices of potential use in quantitative structure activity correlations. We consider graph-theoretical indices such as the connectivity index, topological index, Wiener index and molecular ID indices. Several structural and geometry-dependent indices can be derived from semiempirical and ab initio quantum calculations based on the charge densities, overlap matrices, frontier orbitals, molecular hardness, free valence, density matrices, quantum spectral difference indices, quantum spectral indices and bond matrices. Finally, the use of electrostatic potentials and charge densities for the prediction of reactive sites will be discussed.
Hydrothermally stable heterogeneous catalysts for conversion of biorenewables

The catalytic conversion of biomass-derived molecules to fuels and chemicals involves reactions carried out in the aqueous phase. The corrosive effects of the reactive environment can cause degradation of heterogeneous catalysts, but the detrimental effects depend on the state of water. For example, water vapor, superheated steam and sub- and supercritical liquid water can behave very different from each other. In this review, we focus on the hydrothermal stability of the heterogeneous catalysts in order of the increasing severity of the reaction medium: superheated steam, liquid water at temperatures below 200 °C, liquid water at temperatures above 200 °C and supercritical water. This review addresses changes in the physical structure of heterogeneous catalysts used for biomass conversion reactions. These physical changes influence the catalytic performance, but other causes for deactivation include sintering of the metal phase or coking or carbon deposition on catalysts. The latter phenomena are not the primary focus of this review. We also describe recent approaches designed to improve the hydrothermal stability of heterogeneous catalysts in biomass conversion reactions.
Thermal Buffering of Receivers for Parabolic Dish Solar Thermal Power Plants

A parabolic dish solar thermal power plant comprises a field of parabolic dish power modules where each module is composed of a two-axis tracking parabolic dish concentrator which reflects sunlight (insolation) into the aperture of a cavity receiver at the focal point of the dish. The heat generated by the solar flux entering the receiver is removed by a heat transfer fluid. In the dish power module, this heat is used to drive a small heat engine/generator assembly which is directly connected to the cavity receiver at the focal point. A computer analysis is performed to assess the thermal buffering characteristics of receivers containing sensible and latent heat thermal energy storage. Parametric variations of the thermal inertia of the integrated receiver-buffer storage systems coupled with different fluid flow rate control strategies are carried out to delineate the effect of buffer storage, the transient response of the receiver-storage systems and corresponding fluid outlet temperature. It is concluded that addition of phase change buffer storage will substantially improve system operational characteristics during periods of rapidly fluctuating insolation due to cloud passage.
High Resolution Spectroscopy of X-ray Quasars: Searching for the X-ray Absorption from the Warm-Hot Intergalactic Medium

We present a survey of six low to moderate redshift quasars with Chandra and XMM-Newton. The primary goal is to search for the narrow X-ray absorption lines produced by highly ionized metals in the Warm-Hot Intergalactic Medium. All the X-ray spectra can be well fitted by a power law with neutral hydrogen absorption. Only one feature is detected at above 3-sigma level in all the spectra, which is consistent with statistic fluctuation. We discuss the implications in our understanding of the baryon content of the universe. We also discuss the implication of the non-detection of the local (z approx. 0) X-ray absorption.
An overview of the mechanisms of NOx reduction with oxygenates over zeolite and γ-Al2O3 catalysts

The selective reduction of NO x with added oxygenates over BaNa/Y and Ag/Y zeolites and Ag/γ-Al 2 O 3 takes place via complex reaction pathways with a number of common crucial intermediates. Acetate ions are formed by the oxidation of acetaldehyde over these catalysts. These acetate ions react with NO 2 to form nitromethane which decomposes to HNCO via a dinitro-C 1 intermediate. HNCO hydrolyzes to form NH 3 which can react with HONO to form ammonium nitrite. This NH 4 NO 2 efficiently decomposes to N 2 and H 2 O at 100 °C, and at even lower temperatures in an acidic environment. The neutral surface species are expected to be in equilibrium with their ions. The rate-limiting step in these reaction sequences is the reaction of acetate ions to form nitromethane. When nitromethane is directly added to a NO x stream over Ag/Y, ∼100% conversion of NO x to N 2 is achieved at temperatures as low as 140 °C. In such schemes, NO acts as a reductant of nitrate ions, ammonium nitrate and nitric acid. The benefits of isotopically labeled compounds in the elucidation of such reaction mechanisms and for providing insights into reaction dynamics are also discussed.
Allogeneic B cell response to H-Y minor histocompatibility antigens after donor lymphocyte infusion correlates with disease response

Abstract Donor lymphocyte infusion (DLI) can induce remission in many patients who relapse after allogeneic hematopoietic stem cell transplantation (HSCT). We have previously demonstrated that male HSCT patients with female donors frequently develop high-titer antibody responses to H-Y antigens that correlate with disease remission. DLI administered 6 months after T cell depleted HSCT results in a five-fold increase in peripheral B cell numbers. We sought to determine whether allogeneic B cell responses develop after DLI. We expressed 5 recombinant H-Y proteins (DBY, UTY, ZFY, RPS4Y and EIF1AY) and developed sensitive ELISA to quantify the development of specific anti-HY antibodies. First, we studied prophylactic DLI. Twenty-six patients who received T cell depleted HSCT followed 5–7 months later by prophylactic CD8 depleted DLI were tested for H-Y antibodies pre-DLI and 6–12 months after DLI. No H-Y antibodies were detected in any of the pre-DLI serum samples. However, all 6 male HSCT patients with female donors (F→M HSCT) developed high-titer antibodies against at least one H-Y antigen after DLI. In contrast, only 1/20 of the other donor/recipient gender combinations (4 M→M, 8 F→F, 8 M→F) resulted in H-Y antibody (p H-Y Antibody Results in Male Patients with Female Donors Any H-Y Antibody 2 or more H-Y Antibodies TCD HSCT + prophylactic CD8 depleted DLI 6/6 (100%) 4/6 (67%) TCD HSCT alone 3/9 (33%) 1/9 (11%) CD8 depleted DLI for relapse 9/12 (75%) 9/12 (75%) Unmanipulated DLI for relapse 8/12 (67%) 2/12 (17%)
Predictive control of parabolic PDEs with state and control constraints

This work focuses on predictive control of linear parabolic partial differential equations (PDEs) with state and control constraints. Initially, the PDE is written as an infinite-dimensional system in an appropriate Hilbert space. Next, modal decomposition techniques are used to derive a finite-dimensional system that captures the dominant dynamics of the infinite-dimensional system, and express the infinite-dimensional state constraints in terms of the finite-dimensional system state constraints. A number of model predictive control (MPC) formulations, designed on the basis of different finite-dimensional approximations, are then presented and compared. The closed-loop stability properties of the infinite-dimensional system under the low order MPC controller designs are analysed, and sufficient conditions that guarantee stabilization and state constraint satisfaction for the infinite-dimensional system under the reduced order MPC formulations are derived. Other formulations are also presented which differ in the way the evolution of the fast eigenmodes is accounted for in the performance objective and state constraints. The impact of these differences on the ability of the predictive controller to enforce closed-loop stability and state constraints satisfaction in the infinite-dimensional system is analysed. Finally, the MPC formulations are applied through simulations to the problem of stabilizing the spatially-uniform unstable steady-state of a linear parabolic PDE subject to state and control constraints. Copyright © 2006 John Wiley & Sons, Ltd.
Does decrease in copying cost support copyright term extension

Abstract Copyright duration has been or is being extended in many countries. Technological and demographical changes were cited by a US Senate report to argue for US copyright term extension. This paper analyzes the validity of the arguments. Simulation of a model of the information product market indicates that a decrease in copying cost of information products due to digital technologies calls for a reduction of copyright duration. Partial support is found for the argument that longer life expectancy and delayed child-bearing may support copyright term extension. Furthermore, an increase in demand for information products is found to call for reduction in copyright duration.
A 1,3-Diaza-Claisen rearrangement that affords guanidines.

N-Alkyl-N‘-tosylthioureas activated by EDCI react with azanorbonenes at room temperature through a 1,3-diaza-Claisen rearrangement, affording highly substituted, bicyclic guanidines in moderate to good yields.
Synthesis of a Family of Solids Through the Building-Block Approach: A Case Study with Ag + Substitution in the Ternary Na-Ge-Se System

A new family of Ag-substituted pseudoquaternary alkali-seleno-germanates has been synthesized by two solid-state routes: the conventional flux method and metathesis. This family includes a series of semiconductors with varying amounts of Ag+ substituted for Na+ in Na8Ge4Se10 to form AgxNa(8-x)Ge4Se10, [x = 0.31 (I), 0.67 (II), 0.77 (III), 0.87 (IV), 1.05 (V), 1.09 (VI)] and another phase with a different composition AgxNa(6-x)Ge2Se7 (x = 1.76), VII, related to Na6Ge2Se7. In I−VI, Ge4Se108- constitutes a 6-membered chairlike unit with a Ge−Ge bond, while in VII, a corner-shared dimer of GeSe4 tetrahedra (Ge2Se76-) acts as the building unit. The single-crystal structure analysis indicates that there is a phase transition from P1 to C2/c, in changing from pure Na8Ge4Se10 to AgxNa(8-x)Ge4 Se10 (I−VI), while there is no phase transition between pure Na6Ge2Se7 and AgxNa(6-x)Ge2Se7 (x = 1.76). The structures of I−VI may be described in terms of layers of cubic close-packed Se2- anions. In between the Se layers...
Hamiltonian Approach to Multi-dimensional Screening

Abstract In this paper, I consider a problem of multi-dimensional screening in the case when the number of consumer’s characteristics, m , differs from n , the number of goods produced by a monopolist. I show that, in the case when n > m , the qualitative features of solution are similar to those obtained by Rochet and Chone (1998) for the case n = m . When the monopolist has too few instruments ( n m ), new qualitative features arise. In particular, there are distortions in the outward direction at the top, discontinuity in the bundle of goods consumed on the lower boundary of participation region, and full separation of types is impossible over any open subset of type space.
On the Learning Behavior of Adaptive Networks—Part II: Performance Analysis

Part I of this paper examined the mean-square stability and convergence of the learning process of distributed strategies over graphs. The results identified conditions on the network topology, utilities, and data in order to ensure stability; the results also identified three distinct stages in the learning behavior of multiagent networks related to transient phases I and II and the steady-state phase. This Part II examines the steady-state phase of distributed learning by networked agents. Apart from characterizing the performance of the individual agents, it is shown that the network induces a useful equalization effect across all agents. In this way, the performance of noisier agents is enhanced to the same level as the performance of agents with less noisy data. It is further shown that in the small step-size regime, each agent in the network is able to achieve the same performance level as that of a centralized strategy corresponding to a fully connected network. The results in this part reveal explicitly which aspects of the network topology and operation influence performance and provide important insights into the design of effective mechanisms for the processing and diffusion of information over networks.
Who Moonlights and Why? Evidence from the SIPP

Moonlighting workers represent a significant and growing percentage of the labor force, yet few studies examine the reasons for and economic consequences of this decision. Possible motives for moonlighting include the inability to work sufficient hours on the primary job and the desire for a nonpecuniary aspect of the second job that is unavailable on the primary job. Using data from the SIPP, we present descriptive and econometric evidence on moonlighting behavior in an attempt to reveal who moonlights and why. Our results suggest that both motives are present, with constraints on the primary job being the more common one. In addition, we find that the typical moonlighter remains somewhat poorer than the average worker despite working full time on his primary job and part time on a lower-paying second job.
On the Number of Incipient Spanning Clusters

In critical percolation models, in a large cube there will typically be more than one cluster of comparable diameter. In 2D, the probability of k ⪢ 1 spanning clusters is of the order e−αk2. In dimensions d > 6, when η = 0 the spanning clusters proliferate: for L → ∞ the spanning probability tends to one, and there typically are ≈ Ld−6 spanning clusters of size comparable to |Cmax|L4. The rigorous results confirm a generally accepted picture for d > 6, but also correct some misconceptions concerning the uniqueness of the dominant cluster. We distinguish between two related concepts: the Incipient Infinite Cluster, which is unique partly due to its construction, and the Incipient Spanning Clusters, which are not. The scaling limits of the ISC show interesting differences between low (d = 2) and high dimensions. In the latter case (d > 6?) we find indication that the double limit: infinite volume and zero lattice spacing, when properly defined would exhibit both percolation at the critical state and infinitely many infinite clusters.
Hamiltonian description of the ideal fluid

The Hamiltonian viewpoint of fluid mechanical systems with few and infinite number of degrees of freedom is described. Rudimentary concepts of finite-degree-of-freedom Hamiltonian dynamics are reviewed, in the context of the passive advection of a scalar or tracer field by a fluid. The notions of integrability, invariant-tori, chaos, overlap criteria, and invariant-tori breakup are described in this context. Preparatory to the introduction of field theories, systems with an infinite number of degrees of freedom, elements of functional calculus and action principles of mechanics are reviewed. The action principle for the ideal compressible fluid is described in terms of Lagrangian or material variables. Hamiltonian systems in terms of noncanonical variables are presented, including several examples of Eulerian or inviscid fluid dynamics. Lie group theory sufficient for the treatment of reduction is reviewed. The reduction from Lagrangian to Eulerian variables is treated along with Clebsch variable decompositions. Stability in the canonical and noncanonical Hamiltonian contexts is described. Sufficient conditions for stability, such as Rayleigh-like criteria, are seen to be only sufficient in the general case because of the existence of negative-energy modes, which are possessed by interesting fluid equilibria. Linearly stable equilibria with negative energy modes are argued to be unstable whenmore » nonlinearity or dissipation is added. The energy-Casimir method is discussed and a variant of it that depends upon the notion of dynamical accessibility is described. The energy content of a perturbation about a general fluid equilibrium is calculated using three methods. {copyright} {ital 1998} {ital The American Physical Society}« less
THE END OF THE MACHO ERA: LIMITS ON HALO DARK MATTER FROM STELLAR HALO WIDE BINARIES

We simulate the evolution of halo wide binaries in the presence of the massive compact halo objects (MACHOs) and compare our results to the sample of wide binaries in a companion paper. The observed distribution is well fitted by a single power law for angular separations, 35 43 M☉ at the standard local halo density ρH. This all but removes the last permitted window for a full MACHO halo for masses M > 10-7.5 M☉.
Molecular “Iron Maidens”: Ultrashort Nonbonded Contacts in Cyclophanes and Other Crowded Molecules

Ultrashort nonbonded interactions involving aromatic rings should be the sole province of cyclophane chemists, but it is not always so. In this review, the structures, syntheses, and properties of molecules exhibiting the closest nonbonded contacts of various atoms and functional groups with the faces of aromatic rings are discussed and illustrated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Knoevenagel Condensation of Aldehydes with Meldrum's Acid in Ionic Liquids

Abstract The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in the recyclable ionic liquid [bmim]BF4 at room temperature in the presence of catalytic amounts of piperidine.
Conformational identification of cyclohexylphosphine by microwave spectroscopy

Abstract The microwave spectra of cyclohexylphosphine have been recorded in the 18.0–26.5 GHz region. A -type rotational transitions have been assigned. The ground state rotational constants were determined to be A = 4153.75 ± 0.23, B = 1362.31 ± 0.01 and C = 1104.14 ± 0.01 MHz for C 6 H 11 PH 2 , and A = 4030.03 ± 0.25, B = 1312.72 ± 0.01 and C = 1072.33 ± 0.01 MHz for C 6 H 11 PD 2 . From the experimental rotational constants, it is suggested that the assigned spectra have resulted from the chair conformation with the gauche phosphine group in an equatorial position (CESG). This form is believed to be the most populated conformational isomer in the gas phase.
Photon Propagation around Compact Objects and the Inferred Properties of Thermally Emitting Neutron Stars

Anomalous X-ray pulsars, compact nonpulsing X-ray sources in supernova remnants, and X-ray bursters are three distinct types of sources for which there are viable models that attribute their X-ray spectra to thermal emission from the surface of a neutron star. Inferring the surface area of the emitting regions in such systems is crucial in assessing the viability of different models and in providing bounds on the radii of neutron stars. We show that the spectroscopically inferred areas of the emitting regions may be over- or underestimated by a factor of 2, because of the three-dimensional geometry of the system and general relativistic light deflection, combined with the effects of phase averaging. Such effects make the determination of neutron star radii uncertain, especially when compared to the ~5% level required for constraining the equation of state of neutron star matter. We also note that, for a given spectral shape, the inferred source luminosities and pulse fractions are anticorrelated because they depend on the same properties of the emitting regions, namely, their sizes and orientations. As a result, brighter sources have on average weaker pulsation amplitudes than fainter sources. We argue that this property can be used as a diagnostic tool in distinguishing between different spectral models. As an example, we show that the high inferred pulse fraction and brightness of the pulsar RXS J1708-40 are inconsistent with isotropic thermal emission from a neutron star surface. Finally, we discuss the implication of our results for surveys in the soft X-rays for young, cooling neutron stars in supernova remnants and show that the absence of detectable pulsations from the compact source at the center of Cas A (at a level of 30%) is not a strong argument against its identification with a spinning neutron star.
Muc1 is protective during kidney ischemia - Reperfusion injury

Ischemia-reperfusion injury (IRI) due to hypotension is a common cause of human acute kidney injury (AKI). Hypoxia-inducible transcription factors (HIFs) orchestrate a protective response in renal endothelial and epithelial cells in AKI models. As human mucin 1 (MUC1) is induced by hypoxia and enhances HIF-1 activity in cultured epithelial cells, we asked whether mouse mucin 1 (Muc1) regulates HIF-1 activity in kidney tissue during IRI. Whereas Muc1 was localized on the apical surface of the thick ascending limb, distal convoluted tubule, and collecting duct in the kidneys of sham-treated mice, Muc1 appeared in the cytoplasm and nucleus of all tubular epithelia during IRI. Muc1 was induced during IRI, and Muc1 transcripts and protein were also present in recovering proximal tubule cells. Kidney damage was worse and recovery was blocked during IRI in Muc1 knockout mice compared with congenic control mice. Muc1 knockout mice had reduced levels of HIF-1α, reduced or aberrant induction of HIF-1 target genes involved in the shift of glucose metabolism to glycolysis, and prolonged activation of AMP-activated protein kinase, indicating metabolic stress. Muc1 clearly plays a significant role in enhancing the HIF protective pathway during ischemic insult and recovery in kidney epithelia, providing a new target for developing therapies to treat AKI. Moreover, our data support a role specifically for HIF-1 in epithelial protection of the kidney during IRI as Muc1 is present only in tubule epithelial cells.
The origin of pre-neoplastic metaplasia in the stomach: Chief cells emerge from the Mist

The digestive-enzyme secreting, gastric epithelial chief (zymogenic) cell is remarkable and underappreciated. Here, we discuss how all available evidence suggests that mature chief cells in the adult, mammalian stomach are postmitotic, slowly turning over cells that arise via a relatively long-lived progenitor, the mucous neck cell, The differentiation of chief cells from neck cells does not involve cell division, and the neck cell has its own distinct pattern of gene expression and putative physiological function. Thus, the ontogeny of the normal chief cell lineage exemplifies transdifferentiation. Furthermore, under pathophysiogical loss of acid-secreting parietal cell, the chief cell lineage can itself trasndifferentiate into a mucous cell metaplasia designated Spasmolytic Polypeptide Expressing Metaplasia (SPEM). Especially in the presence of inflammation, this metaplastic lineage can regain proliferative capacity and, in humans may also further differentiate into intestinal metaplasia. The results indicate that gastric fundic lineages display remarkable plasticity in both physiological ontogeny and pathophysiological pre-neoplastic metaplasia.
Cointegration of firm strategies within groups: a long-run analysis of firm behavior in the Japanese steel industry

This paper uses cointegration analysis to study the competitive interaction among firms within the integrated and minimill groups in the Japanese steel industry. The use of cointegration analysis overcomes some of the limitations associated with prior attempts at modeling firm behavior within groups, and allows us to model strategies that take considerable time to adjust. Results indicate that several strategies displayed slow adjustment characteristics. All of the strategies that displayed these properties were cointegrated within the group. Finally, over the long run, the rate of strategic response to ‘shocks’ in the system varied across members and strategies: some converged, while others diverged from the group relationship. We conclude by discussing the relevance of our findings to research on strategic groups and competitive dynamics among firms. Thus the paper contributes to the literature on strategic groups and competitive dynamics, and illustrates the use of cointegration analyses to study the competitive behavior of firms. Copyright © 2002 John Wiley & Sons, Ltd.
Categorical Morita Equivalence for Group-Theoretical Categories

A finite tensor category is called pointed if all its simple objects are invertible. We find necessary and sufficient conditions for two pointed semisimple categories to be dual to each other with respect to a module category. Whenever the dual of a pointed semisimple category with respect to a module category is pointed, we give explicit formulas for the Grothendieck ring and for the associator of the dual. This leads to the definition of categorical Morita equivalence on the set of all finite groups and on the set of all pairs (G, ω), where G is a finite group and ω ∊ H 3(G, k ×). A group-theoretical and cohomological interpretation of this relation is given. A series of concrete examples of pairs of groups that are categorically Morita equivalent but have nonisomorphic Grothendieck rings are given. In particular, the representation categories of the Drinfeld doubles of the groups in each example are equivalent as braided tensor categories and hence these groups define the same modular data.
Better Security for Deterministic Public-Key Encryption: The Auxiliary-Input Setting

Deterministic public-key encryption, introduced by Bellare, Boldyreva, and O'Neill (CRYPTO '07), provides an alternative to randomized public-key encryption in various scenarios where the latter exhibits inherent drawbacks. A deterministic encryption algorithm, however, cannot satisfy any meaningful notion of security when the plaintext is distributed over a small set. Bellare et al. addressed this difficulty by requiring semantic security to hold only when the plaintext has high min-entropy from the adversary's point of view. In many applications, however, an adversary may obtain auxiliary information that is related to the plaintext. Specifically, when deterministic encryption is used as a building block of a larger system, it is rather likely that plaintexts do not have high min-entropy from the adversary's point of view. In such cases, the framework of Bellare et al. might fall short from providing robust security guarantees. We formalize a framework for studying the security of deterministic public-key encryption schemes with respect to auxiliary inputs. Given the trivial requirement that the plaintext should not be efficiently recoverable from the auxiliary input, we focus on hard-to-invert auxiliary inputs. Within this framework, we propose two schemes: the first is based on the d-linear assumption for any d?1 (including, in particular, the decisional Diffie---Hellman assumption), and the second is based on a rather general class of subgroup indistinguishability assumptions (including, in particular, the quadratic residuosity assumption and Paillier's composite residuosity assumption). Our schemes are secure with respect to any auxiliary input that is subexponentially hard to invert (assuming the standard hardness of the underlying computational assumptions). In addition, our first scheme is secure even in the multi-user setting where related plaintexts may be encrypted under multiple public keys. Constructing a scheme that is secure in the multi-user setting (even without considering auxiliary inputs) was identified by Bellare et al. as an important open problem.
Maintenance rituximab after autologous stem cell transplant for high-risk B-cell lymphoma induces prolonged and severe hypogammaglobulinemia.

Maintenance rituximab after autologous stem cell transplant for high-risk B-cell lymphoma induces prolonged and severe hypogammaglobulinemia