cssi/SciSciGPT-SciSciNet huggingface dataset:
Strategic Communication with Lying Costs

I study a model of strategic communication between an uninformed Receiver and an informed but upwardly biased Sender. The Sender bears a cost of lying, or more broadly, of misrepresenting his private information. The main results show that inflated language naturally arises in this environment, where the Sender (almost) always claims to be of a higher type than he would with complete information. Regardless of the intensity of lying cost, there is incomplete separation, with some pooling on the highest messages. The degree of language inflation and how much information is revealed depend upon the intensity of lying cost. The analysis delivers a framework to span a class of cheap-talk and verifiable disclosure games, unifying the polar predictions they make under large conflicts of interest. I use the model to discuss how the degree of manipulability of information can affect the trade-off between delegation and communication. Copyright 2009, Wiley-Blackwell.
Immunologically mediated membrane damage: The mechanism of complement action and the similarity of lymphocyte-mediated cytotoxicity

The destruction of cells by immune mechanisms proceeds via humoral routes, i.e. by soluble factors, as well as by cellular pathways. Among the former, the most prominent and best known is the complement system. As a consequence of investigations spanning about 100 years. it has been learned that the complement system is made up of 14 proteins, not counting inhibitors and regulatory enzymes. The system can be divided into two pathways of activation and a common cytolytic pathway, as shown in Fig. 1. Five of the proteins (Clq, Clr. Cls. C4* and C2) belong to the classical pathway of complement activation which is usually initiated specifically by antigen-antibody complexes. Three of the complement protelna (B. D and P) belong to the alternative pathway which may be activated specifically or non-specifically. Another complement protein, C3, functions in the classical and the alternative pathway. The other five proteins (CS, C6, C7, C8 and C9) belong to the final common pathway which mediates the cytolytic function of complement by damaging the membranes of targets such as bacteria, protozoa, fungi and cells of higher organisms. In addition to the cytotoxic action, activation of the complement system, either via the classical or the alternative pathway, generates fragments of C3 and C5, by enzymatic cleavage, which mediate a variety of biological activities, notably opsonization (C3b), chemotaxis (C5a), release of
Signed shape tilings of squares

Abstract Let T be a tile made up of finitely many rectangles whose corners have rational coordinates and whose sides are parallel to the coordinate axes. This paper gives necessary and sufficient conditions for a square to be tilable by finitely many Q -weighted tiles with the same shape as T, and necessary and sufficient conditions for a square to be tilable by finitely many Z -weighted tiles with the same shape as T. The main tool we use is a variant of F.W. Barnes's algebraic theory of brick packing, which converts tiling problems into problems in commutative algebra.
Tunneling into fuzzball states

String theory suggests that black hole microstates are quantum, horizon sized ‘fuzzballs’, rather than smooth geometries with horizon. Radiation from fuzzballs can carry information and does not lead to information loss. But if we let a shell of matter collapse then it creates a horizon, and it seems that subsequent radiation will lead to information loss. We argue that the resolution to this problem is that the shell can tunnel to the fuzzball configurations. The amplitude for tunneling is small because we are relating two macroscopically different configurations, but the number of states that we can tunnel to, given through the Bekenstein entropy, is very large. These small and large numbers can cancel each other, making it possible for the shell to tunnel into fuzzball states before a significant amount of radiation has been emitted. This offers a way to resolve the information paradox.
Malliavin calculus for infinite-dimensional systems with additive noise

Abstract We consider an infinite-dimensional dynamical system with polynomial nonlinearity and additive noise given by a finite number of Wiener processes. By studying how randomness is spread by the dynamics, we develop in this setting a partial counterpart of Hormander's classical theory of Hypoelliptic operators. We study the distributions of finite-dimensional projections of the solutions and give conditions that provide existence and smoothness of densities of these distributions with respect to the Lebesgue measure. We also apply our results to concrete SPDEs such as a Stochastic Reaction Diffusion Equation and the Stochastic 2D Navier–Stokes System.
Feedback Effects on Low-mass Star Formation

Protostellar feedback, both radiation and bipolar outflows, dramatically affects the fragmentation and mass accretion from star-forming cores. We use ORION, an adaptive mesh refinement gravito-radiation-hydrodynamics code, to simulate low-mass star formation in a turbulent molecular cloud in the presence of protostellar feedback. We present results of the first simulations of a star-forming cluster that include both radiative transfer and protostellar outflows. We run four simulations to isolate the individual effects of radiation feedback and outflow feedback as well as the combination of the two. We find that outflows reduce protostellar masses and accretion rates each by a factor of three and therefore reduce protostellar luminosities by an order of magnitude. This means that, while radiation feedback suppresses fragmentation, outflows render protostellar radiation largely irrelevant for low-mass star formation above a mass scale of 0.05 M ☉. We find initial fragmentation of our cloud at half the global Jeans length, around 0.1 pc. With insufficient protostellar radiation to stop it, these 0.1 pc cores fragment repeatedly, forming typically 10 stars each. The accretion rate in these stars scales with mass as predicted from core accretion models that include both thermal and turbulent motions; the accretion rate does not appear to be consistent with either competitive accretion or accretion from an isothermal sphere. We find that protostellar outflows do not significantly affect the overall cloud dynamics, in the absence of magnetic fields, due to their small opening angles and poor coupling to the dense gas. The outflows reduce the mass from the cores by 2/3, giving a core to star efficiency, core 1/3. The simulations are also able to reproduce many observation of local star-forming regions. Our simulation with radiation and outflows reproduces the observed protostellar luminosity function. All of the simulations can reproduce observed core mass functions, though we find they are sensitive to telescope resolution. We also reproduce the two-point correlation function of these observed cores. Lastly, we reproduce the initial mass function itself, including the low-mass end, when outflows are included.
Diamagnetic boundary layers: A kinetic theory

We present a kinetic theory for boundary layers associated with MHD tangential ‘discontinuities’ in a collisionless magnetized plasma such as those observed in the solar wind. The theory consists of finding self-consistent solutions of Vlasov's equation and Maxwell's equation for stationary, one-dimensional boundary layers separating two Maxwellian plasma states. Layers in which the current is carried by electrons are found to have a thickness of the order of a few electron gyroradii, but the drift speed of the current-carrying electrons is found to exceed the Alfven speed, and accordingly such layers are not stable. Several types of layers, in which the current is carried by protons are discussed; in particular, we considered cases in which the magnetic field intensity and/or direction changed across the layer. In every case, the thickness was of the order of a few proton gyroradii and the field changed smoothly, although the characteristics depended somewhat on the boundary conditions. The drift speed was always less than the Alfven speed, consistent with stability of such structures. Our results are consistent with the observations of boundary layers in the solar wind near 1 AU.
Systematic study of Au–Au collisions with AGS experiment E917

The systematics of baryon stopping and strange particle production have been studied in Au+Au collisions at 6, 8, and 10.8 GeV per nucleon with AGS experiment E917. In particular, the systematic behavior of the proton yields, phi meson production, and the yields of antilambdas and antiprotons are examined as functions of beam energy and centrality.
Facile synthesis of 4,5,6a,7-tetrahydrodibenzo[de,g]chromene heterocycles and their transformation to phenanthrene alkaloids

Oxa-Pictet-Spengler cyclization and microwave-assisted C-H arylation have been implemented as key steps in the synthesis of new isochroman heterocycles containing a 4,5,6a,7-tetrahydrodibenzo[de,g]chromene motif. These isochromans may be easily transformed to phenanthrene alkaloids via acidic cleavage of the isochroman ring and standard synthetic manipulations thereafter. The route described is attractive in that it provides access to two biologically interesting scaffolds in simple and high yielding synthetic steps.
Syntheses, Properties, and Potential Applications of Multicomponent Magnetic Nanoparticles†

Multicomponent hybrid nanostructures that contain two or more nanometer-scale components have attracted much attention recently owing to the synergistic properties induced by interactions between these different nanometer-scale objects. Herein, we give an overview of the efforts to synthesize multicomponent nanoparticles with at least one component being magnetic, and focus on our recent developments. The syntheses are based on heterogeneous nucleation and growth of a second and third component onto seed nanoparticles. These multicomponent nanoparticles show interesting magnetic, magneto-optical, plasmonic, and semiconducting properties that can be modulated by interfacial interactions between different nanocomponents. This opens up a new avenue to advanced multifunctional nanomaterials for device concepts and applications.
Formation of Pyrazoles and of Imidazoles from Phenacyl Ketal Hydrazones of Aldehydes

The cyclization of phenacyl ethylene ketal (pek) hydrazones of glyoxals, benzaldehyde and acetaldehyde to the pyrazoles is described; in the case of the hydrazones of benzaldehyde and acetaldehyde, the corresponding imidazoles are also formed. A mechanism is suggested for the formation of the imidazoles.
Numerical investigation of the spreading of self-excited stratified jets

Direct numerical simulations are performed to investigate the structure and evolution of self-excited subsonic periodic arrays of jets of constant and variable fluid density. The method of investigation is based on spectral element discretization procedures that achieve high-order accuracy and are appropriate for simulations of highly unsteady transitional flows. In particular, in this work we examine the spreading of a low-density, high-velocity jet surrounded by heavy-density side-jets in planar two- and three-dimensional configurations. The dynamics of stratified jets and thereby their spreading are considerably different from the dynamics of jets in a uniform density environment. Depending on its initial momentum the density ratio and the velocity ratio with respect to the ambient fluid, the lighter jet may be constrained to a small region or may bifurcate to a limit cycle. At higher momentum fluxes the flow symmetry is lost and large entrainment rates are obtained involving the surrounding irrotational heavier fluid. The instability of the center jet is sensitive to the the momentum flux of the side jets; in particular, the severity of instability is increased as the side-momentum flux increases or the center jet becomes lighter for the same dynamic head. Results presented for low and high side-momentum flux reveal a shifting of the origin of instability from the near-field to the far-field respectively, and suggest possible routes of destabilization.
X‐Ray Absorption Fine Structure Spectra and the Oxidation State of Nickel in Some of Its Oxycompounds

The structure of the higher oxide forms of nickel (where Ni has a valency greater than +2) is interesting from the standpoint of developing advanced nickel batteries for consumer applications and for electric vehicle propulsion. Xanes spectra of nickel K-edge and X-ray diffraction patterns of several nickel oxycompounds were measured. The shift in energy of the Ni K-absorption edge toward higher values correlates well with the increase in the oxidation state of nickel from +2 to +4 in the compounds studied. The inflection point energy of the Ni pre-edge structure shifts approximately 1 eV per unit change in valency. The results provide evidence which support the assignment that the valency of Ni in [beta]-NiOOH is +3; Ni[sub 3]O[sub 2](OH)[sub 4] and commercial nickel peroxide (NiO[sub 2]) likewise contain trivalent nickel. The edge shift for quadrivalent nickel in KNilO[sub 6] is reported for the first time.
Fast-light in a photorefractive crystal for gravitational wave detection

We demonstrate superluminal light propagation using two frequency multiplexed pump beams to produce a gain doublet in a photorefractive crystal of Ce:BaTiO3. The two gain lines are obtained by two-wave mixing between a probe field and two individual pump fields. The angular frequencies of the pumps are symmetrically tuned from the frequency of the probe. The frequency difference between the pumps corresponds to the separation of the two gain lines; as it increases, the crystal gradually converts from normal dispersion without detuning to an anomalously dispersive medium. The time advance is measured as 0.28 sec for a pulse propagating through a medium with a 2Hz gain separation, compared to the same pulse propagating through empty space. We also demonstrate directly anomalous dispersion profile using a modified experimental configuration. Finally, we discuss how anomalous dispersion produced this way in a faster photorefractive crystal (such as SPS: Sn2P2S6) could be employed to enhance the sensitivity-bandwidth product of a LIGO type gravitational wave detector augmented by a White Light Cavity.
Cultural Innovations and Demographic Change

Demography plays a large role in cultural evolution through its effects on the effective rate of innovation. If we assume that useful inventions are rare, then small isolated societies will have low rates of invention. In small populations, complex technology will tend to be lost as a result of random loss or incomplete transmission (the Tasmanian effect). Large populations have more inventors and are more resistant to loss by chance. If human populations can grow freely, then a population-technology-population positive feedback should occur such that human societies reach a stable growth path on which the rate of growth of technology is limited by the rate of invention. This scenario fits the Holocene to a first approximation, but the late Pleistocene is a great puzzle. Large-brained hominins existed in Africa and west Eurasia for perhaps 150,000 years with, at best, slow rates of technical innovation. The most sophisticated societies of the last glacial period appear after 50,000 years ago and were apparently restricted to west and north-central Eurasia and North Africa. These patterns have no simple, commonly accepted explanation. We argue that increased high-frequency climate change around 70,000-50,000 years ago may have tipped the balance between humans and their competitor-predators, such as lions and wolves, in favor of humans. At the same time, technically sophisticated hunters would tend to overharvest their prey. Perhaps the ephemeral appearance of complex tools and symbolic artifacts in Africa after 100,000 years ago resulted from hunting inventions that allowed human populations to expand temporarily before prey overexploitation led to human population and technology collapse. Sustained human populations of moderate size using distinctively advanced Upper Paleolithic artifacts may have existed in west Eurasia because cold, continental northeastern Eurasia-Beringia acted as a protected reserve for prey populations.
Synthesis of pyranose glycals via tungsten and molybdenum pentacarbonyl-induced alkynol cyclizations

Abstract The tungsten pentacarbonyl-induced cyclization of an acyclic alkynol substrate bearing protected oxygen and nitrogen functional groups provides the cyclic tungsten oxacarbene, which is readily converted into a pyranose glycal structurally related to the carbohydrate moieties of the pluramycin and vancomycin families of antitumor antibiotics. In addition a molybdenum-catalyzed cycloisomerization procedure provides an alternative route to this pyranose glycal.
On dispersive effect of the Coriolis force for the stationary Navier–Stokes equations

Abstract The dispersive effect of the Coriolis force for the stationary and non-stationary Navier–Stokes equations is investigated. Existence of a unique solution is shown for arbitrary large external force provided the Coriolis force is large enough. In addition to the stationary case, counterparts of several classical results for the non-stationary Navier–Stokes problem have been proven. The analysis is carried out in a new framework of the Fourier–Besov spaces.
What do effective teachers of inner-city children have in common?

This paper investigates the extent to which variables describing the classroom behavior of teachers and variables describing teachers' backgrounds and training explain differences in the effectiveness of teachers in improving the vocabulary skills of inner-city black children in four elementary grade levels. The results indicate that both types of variables explain significant portions of the variation in student achievement. In other words, teachers' choices of techniques matter; and the characteristics of teachers provide some information about their effectiveness. However, the pattern of results indicates that great care must be taken in interpreting individual coefficients. The paper concludes with an interpretation of the results and with suggestions for new directions for research on teaching that follow from this interpretation.
Apparel Selection Criteria Related to Female Consumers' Lifestyle

The purpose of this study was to investigate the relationship of lifestyle and evaluative criteria for apparel. A random sample of 2,000 female consumers, ages 25-44, was sent questionnaires resulting in a 45 percent return rate (n=842). Principal Components Factor Analysis with Varimax Rotation was used to reduce the number of lifestyle and evaluative criteria items to twelve factors. Coefficients of correlation were used to establish relationships between the lifestyle and evaluative criteria factors. Nineteen significant relationships existed between lifestyle and evaluative criteria verifying that consumers choose apparel products thatfit specific roles in their lifestyle. Results will benefit retailers in understanding consumers, educators in preparing students for apparel merchandising positions, and marketing specialists in planning product promotion strategies.
Classification of manifolds with weakly 1/4-pinched curvatures

We show that a compact Riemannian manifold with weakly pointwise 1/4-pinched sectional curvatures is either locally symmetric or diffeomorphic to a space form. More generally, we classify all compact, locally irreducible Riemannian manifolds M with the property that M × R 2 has non-negative isotropic curvature.
Sperm Membrane Incorporation Into Oolemma Contributes to the Oolemma Block to Sperm Penetration: Evidence Based on Intracytoplasmic Sperm Injection Experiments in the Mouse

Mouse oocytes were fertilized by intracytoplasmic sperm injection (ICSI) and reinseminated after the removal of zonae pellucidae at pronuclear stage or at the 2-cell stage. Although these oocytes were activated normally by ICSI, as evidenced by resumption of meiosis and cortical granule exocytosis, they did not develop oolemma block to sperm penetration. They could be penetrated by spermatozoa at pronuclear stage and even at the 2-cell stage. This supports the notion that incorporation of sperm plasma membrane into oolemma contributes to the changes in oolemma that block sperm penetration.
Chaotic mixing in a torus map

The advection and diffusion of a passive scalar is investigated for a map of the 2-torus. The map is chaotic, and the limit of almost-uniform stretching is considered. This allows an analytic understanding of the transition from a phase of constant scalar variance (for short times) to exponential decay (for long times). This transition is embodied in a short superexponential phase of decay. The asymptotic state in the exponential phase is an eigenfunction of the advection–diffusion operator, in which most of the scalar variance is concentrated at small scales, even though a large-scale mode sets the decay rate. The duration of the superexponential phase is proportional to the logarithm of the exponential decay rate; if the decay is slow enough then there is no superexponential phase at all.
Biological indications of active upwelling in the Northwestern Indian Ocean in 1964 and 1979, and a comparison with Peru and Northwest Africa

Abstract When surface properties of the northwestern Indian Ocean observed during the southwest monsoon of 1964 (R.R.S. ‘DISCOVERY’) are compared with those of 1979 (R.V. ‘ISELIN’), the area of upwelling around Ras Hafun (near 10°N) showed the clearest similarity in the two years. The highest surface concentration of chlorophyll a between Mombasa (4°S) and Cabo Guardafui (12°N) occurred near Ras Hafun in both years and was between 4 and 5 mg m−3. Sea-surface temperatures around Ras Hafun were lower than elsewhere along the coast, and surface nitrate was higher. The abundance of the copepod Calanoides carinatus was >100 m−3 there and near 5°N in both years. The age-structure of this dominant copepod suggests active reproduction in both years. Major dissimilarities between 1964 and 1979 were observed in the vertical distribution of temperature and nitrate near 5°N, which suggested that upwelling there in August 1964 was less intense than in July 1979. The intensity of upwelling near 5°N probably reached a peak in July both years, implying a relatively stable annual cycle for the upwellings off Somalia. The relationship of primary productivity and chlorophyll a observed off Somalia is very similar to that observed off Peru, and standing stocks of net zooplankton are also similar, but both are quite different from northwestern Africa. Perhaps the most striking difference, however, is the areal of extent of upwelling off Somalia which is considerably larger than that of the other two upwelling areas.
On a question of D. Shlyakhtenko

In this short paper we construct two countable, infinite conjugacy class (ICC) groups which admit free, ergodic, probability measure-preserving orbit equivalent actions but whose group von Neumann algebras are not (stably) isomorphic.
Silicon-based photonic crystal nanocavity light emitters

We study light emitters based on two-dimensional planar photonic crystal (PC) nanocavities fabricated in silicon rich silicon nitride that exhibits photoluminescence (PL) at 600-800 nm
Unitary groups and spectral sets

Abstract We study spectral theory for bounded Borel subsets of R and in particular finite unions of intervals. For Hilbert space, we take L 2 of the union of the intervals. This yields a boundary value problem arising from the minimal operator D = 1 2 π i d d x with domain consisting of C ∞ functions vanishing at the endpoints. We offer a detailed interplay between geometric configurations of unions of intervals and a spectral theory for the corresponding self-adjoint extensions of D and for the associated unitary groups of local translations. While motivated by scattering theory and quantum graphs, our present focus is on the Fuglede-spectral pair problem. Stated more generally, this problem asks for a determination of those bounded Borel sets Ω in R k such that L 2 ( Ω ) has an orthogonal basis of Fourier frequencies (spectrum), i.e., a total set of orthogonal complex exponentials restricted to Ω. In the general case, we characterize Borel sets Ω having this spectral property in terms of a unitary representation of ( R , + ) acting by local translations. The case of k = 1 is of special interest, hence the interval-configurations. We give a characterization of those geometric interval-configurations which allow Fourier spectra directly in terms of the self-adjoint extensions of the minimal operator D . This allows for a direct and explicit interplay between geometry and spectra.
Low-grade gliomas

ABSTRACTPurpose of Review: Low-grade gliomas present vexing management issues for neuro-oncologists. The relatively long survival compared to other brain tumors makes consideration of treatment toxicity, and thus timing of potentially damaging interventions such as surgery, radiation, and chemothera
Recent developments in ionosphere–thermosphere modeling with an emphasis on solar-variability

Abstract The Utah State University modeling developments have led to new results in several areas of ionospheric research. This review will present the most recent of these results and their synergisms with both ground-based and satellite-based observations. Particular attention is given to new results associated with solar variability, a central theme to the TIGER program. The effect on the ionosphere of differences in solar X-EUV spectra will be demonstrated by studies using the time-dependent ionospheric model, while their effect on the coupled thermosphere–ionosphere system will be shown using a new model, the global average ionosphere thermosphere model. How the dayside solar-produced plasma contributes to sub auroral polarization streams, storm enhanced densities, tongues of ionization, plasma patches, polar wind jets, and polar cap scintillations, will be described via recent modeling results from a variety of coupled or driven thermosphere, ionosphere, and magnetosphere models. The review will indicate the need for improved solar output specification, whether via observations or models. These improvements need to be over the flare through solar cycle time scale, with particular attention to the short wavelength end of the spectrum.
Asymptotic evaluation of WKB matrix elements

A procedure is given for the analytic asymptotic evaluation of certain integrals which arise in the quantum mechanical theory of inelastic molecular collisions. The integrals are evaluated using WKB wavefunctions and the saddle-point method. The method is equivalent to Landau's but is considerably more transparent and is easily applied to vibrational and rotational transitions for which there is no crossing of potential energy surfaces, as well as to electronic transitions near a crossing point. The special case of resonance collisions is discussed and the method is illustrated with an example.
Electron microscopy and the study of microstructure and domain structure of magnetic materials

Abstract Five different electron optical techniques to characterize magnetic domains and domain walls in ferromagnetic materials are reviewed. It is shown that one can choose one or more of these techniques to solve a given problem depending on the nature of the information needed, the resolution level desired and the sophistication of the instrument available. Lorentz microscopy in a transmission electron microscope is a clear choice for most problems although spin-polarized scanning electron microscopy or magnetic force microscopy are better suited to non-destructive surface studies, and differential phase contrast microscopy is preferable for quantitative study of domains in thin specimens. Electron holography is capable of providing contour maps corresponding to lines of force distribution as well as quantitative data on flux distribution. In the near future, it should become possible to combine a few of these techniques with computer simulation to obtain three-dimensional domain wall distributions in bulk ferromagnets.
Dynamics of Polymers in Flowing Colloidal Suspensions

Using hydrodynamic simulations we examine the behavior of single polymers in a confined colloidal suspension under flow. We study the conformations of both, collapsed and noncollapsed polymers. Our results show that the presence of the colloids has a pronounced effect on the unfolding and refolding cycles of collapsed polymers, but does not have a large effect for noncollapsed polymers. Further inspection of the conformations reveals that the strong flow around the colloids and the direct physical compressions exerted on a globular polymer diffusing in between colloidal shear bands largely facilitate the initiation and unraveling of the globular chains. These results are important for rheological studies of (bio)polymer-(bio)colloid mixtures.
The E/Z geometry of the enolate component determines face selection of the aldehyde component in chiral diazaborolidine-directed enantioselective aldol coupling

Abstract An analysis of the effect of enolate geometry on transition-state energy explains the stereochemistry of aldol reactions of acetate and propionate esters with aldehydes using as reagent the chiral diazaborolidine 1.
Structural optimization with frequency constraints

This paper presents a design optimization algorithm for structural weight minimization with multiple frequency constraints. An optimality criterion method based on uniform Lagrangian density for resizing and a scaling procedure to locate the constraint boundary were used in optimization. Multiple frequency constraints of equality and inequality types were addressed. The effectiveness of the algorithm was demonstrated by designing a number of truss structures with as many as 489 design variables. No attempt was made to reduce the number of design variables by such procedures as linking and/or invoking symmetry conditions. The design examples include a 10-bar truss, 200-bar truss, a modified ACOSS-II, and COFS (Control of Flexible Structures) mast truss. All the structures contain nonstructural mass besides their own mass. The algorithm is extremely stable and, in all cases, the optimum designs were obtained in less than 20 iterations regardless of the size of the structure and the number of design variables.
Young Low-Mass Stars and Brown Dwarfs in IC 348

I present new results from a continuing program to identify and characterize the low-mass stellar and substellar populations in the young cluster IC 348 (0.5-10 Myr). Optical spectroscopy has revealed young objects with spectral types as late as M8.25. The intrinsic J-H and H-K colors of these sources are dwarflike, whereas the R-I and I-J colors appear intermediate between the colors of dwarfs and giants. Furthermore, the spectra from 6500 to 9500 A are reproduced well with averages of standard dwarf and giant spectra, suggesting that such averages should be used in the classification of young late-type sources. An H-R diagram is constructed for the low-mass population in IC 348 (K6-M8). The presumably coeval components of the young quadruple system GG Tau (White et al.) and the locus of stars in IC 348 are used as empirical isochrones to test the theoretical evolutionary models. The calculations of Burrows et al. do not appear to be consistent with the data at these earliest stages of stellar evolution. There is fair agreement between the data and the model isochrones of D'Antona & Mazzitelli, except near the hydrogen-burning limit. The agreement cannot be improved by changing the conversion between spectral types and effective temperatures. On the other hand, for the models of Baraffe et al., an adjustment of the temperature scale to progressively warmer temperatures at later M types, intermediate between dwarfs and giants, brings all components of GG Tau onto the same model isochrone and gives the population of IC 348 a constant age and age spread as a function of mass. When other observational constraints are considered, such as the dynamical masses of GM Aur, DM Tau, and GG Tau A, the models of Baraffe et al. are the most consistent with observations of young systems. With compatible temperature scales, the models of both D'Antona & Mazzitelli and Baraffe et al. suggest that the hydrogen-burning mass limit occurs near M6 at ages of 10 Myr. Thus, several likely brown dwarfs are discovered in this study of IC 348, with masses down to ~20-30 MJ.
FOCAL INTERSTITIAL NEPHRITIS IN THE CALF FOLLOWING INTERFERENCE WITH THE NORMAL INTAKE OF COLOSTRUM

An interstitial focal nephritis found in young calves during the 1st or later months of life, associated with or preceded by the invasion of a special, virulent type of Bacillus coli , may be produced by postponing the feeding of colostrum 24 to 36 hours, or by withholding it altogether. In the presence of a virulent type of Bacillus coli few calves completely deprived of colostrum survive the 1st week. Among the survivors, the spotted kidney, the result of Bacillus coli bacteriemia, is frequently encountered. Calves normally fed have not shown the spotted kidney, and such as have been killed early have had uniformly sterile kidneys.
Analytical GMM Tests: Asset Pricing with Time-Varying Risk Premiums

We propose alternative generalized method of moments (GMM) tests that are analytically solvable in many econometric models, yielding in particular analytical GMM tests for asset pricing models with time-varying risk premiums. We also provide simulation evidence showing that the proposed tests have good finite sample properties and that their asymptotic distribution is reliable for the sample size commonly used. We apply our tests to study the number of latent factors in the predictable variations of the returns on portfolios grouped by industries. Using data from October 1941 to September 1986 and two sets of instrumental variables, we find that the tests reject a one-factor model but not a two-factor one. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
Propulsion and staging considerations for an orbital sortie vehicle

Abstract Severe weight penalties can occur if the sizes of Orbital Sortie Vehicle stages are not near their optimum values. In particular, single-stage rocket configurations with or without “zero-stage” boosters are necessarily much larger than two-stage configurations. Conventional cryogenic propellant combinations provide a reasonable range of vehicle sizes. By comparison, one storable-liquid propellant combination would require vehicle size to be excessive, while two “exotic” propellant combinations do not appear to provide enough size reduction to warrant their use. Second-stage structural efficiency has a major effect on overall vehicle size. It appears feasible to design a two-stage Orbital Sortie Vehicle whose gross lift-off weight is 50–70 times the payload weight.
On the quantum cat and sawtooth maps—Return to generic behaviour

Abstract The quantization of the continuous cat maps on the torus has led to rather pathological quantum objects [1]. The non-generic behaviour of this model has led some to conclude that the Correspondence Principle fails in this case [2]. In this note we introduce the quantum sawtooth models, since this is the natural family to which the cap maps belong. Thus, a simple propagator depending on a parameter is constructed which for integer values of the parameter becomes pathological quantum cat maps, while away from integer values we find a return to the generic behaviour of non-integrable quantum systems.
Gaussian radial basis functions and inner product spaces

An approximation result is given concerning Gaussian radial basis functions in a general inner product space. Applications are described concerning the classification of the elements of disjoint sets of signals, and also the approximation of continuous real functions defined on all of ℝ n using radial basis function (RBF) networks. More specifically, it is shown that an important large class of classification problems involving signals can be solved using a structure consisting of only a generalized RBF network followed by a quantizer. It is also shown that Gaussian radial basis functions defined on ℝ n can uniformly approximate arbitrarily well over all of ℝ n any continuous real functionalf on ℝ n that meets the condition that |f(x)|→0 as ‖x‖→∞.
Metal‐Organic Frameworks: A Rapidly Growing Class of Versatile Nanoporous Materials

Metal-organic frameworks (MOFs) represent a new class of hybrid organic-inorganic supramolecular materials comprised of ordered networks formed from organic electron donor linkers and metal cations. They can exhibit extremely high surface areas, as well as tunable pore size and functionality, and can act as hosts for a variety of guest molecules. Since their discovery, MOFs have enjoyed extensive exploration, with applications ranging from gas storage to drug delivery to sensing. This review covers advances in the MOF field from the past three years, focusing on applications, including gas separation, catalysis, drug delivery, optical and electronic applications, and sensing. We also summarize recent work on methods for MOF synthesis and computational modeling.
Stability of asynchronous variational integrators

The adoption of multiple time step integrators can provide substantial computational savings for mechanical systems with multiple time scales. However, the scope of these savings may be limited by the range of allowable time step choices. In this paper we analyze the linear stability of the fully asynchronous methods termed AVI, for asynchronous variational integrators. We perform a detailed analysis for the case of a one-dimensional particle moving under the action of a soft and a stiff quadratic potential, integrated with two time steps in rational ratios. In this case, we provide sufficient conditions for the stability of the method. These generalize to the fully asynchronous AVI case the results obtained for synchronous multiple time stepping schemes, such as r-RESPA, which show resonances when the larger time step is a multiple of the effective half-period of the stiff potential. Additionally, we numerically investigate the appearance of instabilities. Based on the experimental observations, we conjecture the existence of a dense set of unstable time steps when arbitrary rational ratios of time steps are considered. In this way, unstable schemes for arbitrarily small time steps can be obtained. However, the vast majority of these instabilities are extremely weak and do not present an obstacle to the use of these integrators. We then applied these results to analyze the stability of multiple time step integrators in the more complex mechanical systems arising in molecular dynamics and solid dynamics. We explained why strong resonances are ubiquitously found in the former, while rarely encountered in the latter. Finally, in this paper we introduce a formulation of AVI that highlights the symplectic nature of the algorithm, complementing those introduced earlier by other authors.
Noise in strong lensing cosmography

Giant arcs in strong lensing galaxy clusters can provide a purely geometric determination of cosmological parameters, such as the dark energy density and equation of state. We investigate sources of noise in cosmography with giant arcs, focusing in particular on errors induced by density fluctuations along the line of sight and errors caused by modeling uncertainties. We estimate parameter errors in two independent ways, first by developing a Fisher matrix formalism for strong lensing parameters and next by directly ray-tracing through N-body simulations using a multiplane lensing code. We show that for reasonable power spectra, density fluctuations from large-scale structures produce >100% errors in cosmological parameters derived from any single sight line, precluding the use of individual clusters or golden lenses to derive accurate cosmological constraints. Modeling uncertainties can similarly lead to large errors, and we show that the use of parameterized mass models in fitting strong lensing clusters can significantly bias the inferred cosmological parameters. We lastly speculate on the means by which these errors may be corrected.
Embedding AdS Black Holes in Ten and Eleven Dimensions

Abstract We construct the non-linear Kaluza-Klein ansatze describing the embeddings of the U (1) 3 , U (1) 4 and U (1) 2 truncations of D = 5, D = 4 and D = 7 gauged supergravities into the type IIB string and M-theory. These enable one to oxidise any associated lower-dimensional solutions to D = 10 or D = 11. In particular, we use these general ansatze to embed the charged AdS 5 , AdS 4 and AdS 7 black hole solutions in ten and eleven dimensions. The charges for the black holes with toroidal horizons may be interpreted as the angular momenta of D3-branes, M2-branes and M5-branes spinning in the transverse dimensions, in their near-horizon decoupling limits. The horizons of the black holes coincide with the world-volumes of the branes. The Kaluza-Klein ansatze also allow the black holes with spherical or hyperbolic horizons to be reinterpreted in D = 10 or D = 11.
Approximate Solutions to a Dynamic Combinatorial Problem in Space

A family of important problems in spatial economics may be particularized in the following terms. A set of vehicles, V, exists with elements i = 1, ..., m, each of which carries a given initial supply of product. We identify a sequence of ‘legs’, t = 0, 1, ..., N, during which we assume (fictitiously) that vehicle movement occurs. Finally, we specify a set of stations, S, with elements j = 1, ..., n, located at coordinates [x j , y j ] on the plane; for convenience, and without loss of generality, we assume that j = 1, ..., f, f ≤ m, are the initial locations of the vehicles, or the stations at which they are located on Leg 0.
The role of adaptive regulation in the pathophysiology of psychiatric disease

Publisher Summary This chapter discusses the role of adaptive regulation in the pathophysiology of psychiatric disease. When central biogenic amine synapses are impairedby drugs and normal neurotransmitter–receptor interaction is decreased, the receptor function appears capable of compensatory alterations in sensitivity. By maintaining the integrity of the nerve ending fraction during tissue homogenization, one is able to study the rate of conversion of substrate to transmitter as a function of the physical state of the enzyme. Some drugs induce prompt alterations in enzyme activity in nerve ending regions. Morphine inhibits intrasynaptosomal tryptophanhydroxylase activity without altering the rate of substrate uptake. However, a number of other drugs and treatments do alter tryptophan uptake into nerve endings. Changes induced in transmitter dynamics at the nerve ending somehow affect the rate of enzyme synthesis in the cell bodies, and those changes in amount of enzyme can be seen several days later at the nerve ending. Furthermore, the adaptive mechanisms within the brain are the major impediment to any continuing role in mental disorder for an aberrant metabolite, unless they fail.
Probing the structures of leishmanial farnesyl pyrophosphate synthases: homology modeling and docking studies.

Leishmania donovani and Leishmania major farnesyl pyrophosphate synthase (LdFPPS and LmFPPS) are potential targets for the development of antileishmanial therapy. The protein sequence for LdFPPS was recently elucidated in our laboratory. Highly refined homology models were generated using the protein sequences of LdFPPS and the closely related LmFPPS enzyme. A ligand-refined model of LmFPPS with a bound bisphosphonate ligand was generated using restraint-guided molecular mechanics followed by quantum mechanics/molecular mechanics refinement. The ligand-refined model of LmFPPS was further validated through extensive pose validation, enrichment, and other docking studies involving known bisphosphonate inhibitors. The model was able to explain the critical binding site interactions and site-directed mutagenesis data obtained from experimental studies on related FPPS enzymes. The ligand-refined model in conjunction with the validated docking protocol could be utilized in the future for structure-based virtual...
A wafer-scale digital integrator using restructurable VSLI

Wafer-scale integration has been demonstrated by fabricating a digital integrator on a monolithic 20-cm2silicon chip, the first laser-restructured digital logic system. Large-area integration is accomplished by laser programming of metal interconnect for defect avoidance. This paper describes the technology for laser welding and cutting, the design methodology and CAD tools developed for wafer-scale integration, and the integrator itself.
Functional inversion and communication complexity

We study the relationship between the multiparty communication complexity of functions over certain communication topologies and the complexity of inverting those functions. We show that if a function ofn variables has aring-protocol or atree-protocol of communication complexity bounded by ?, then there is a circuit of size $$2^{0(\phi )} n$$ that computes an inverse of the function. Consequently, we prove that although invertingNC 0 Boolean circuits isNP-hard, planarNC 1 Boolean circuits can be inverted inNC, and hence in polynomial time. From the ring-protocol theorem, we derive an ?(n logn) lower bound on the VLSI area required to lay out any one-way function. Our results on inverting boolean circuits can be extended to algebraic circuits over finite rings. We prove that on certain topologies no one-way function can be computed with low communication complexity.
The changing epidemiology of cystic fibrosis.

Data from 17,857 patients with cystic fibrosis submitted in 1990 to the registry maintained by the Cystic Fibrosis Foundation were used to describe their demographic characteristics, survival rates, pulmonary function, anthropometry, microbiologic data, complication rates, and health care utilization. Comparisons with similar data collected in 1969, 1972, and 1978 demonstrated a significant shift in the age distribution of patients with cystic fibrosis. The proportion of adult patients increased fourfold between 1969 (8%) and 1990 (33%). In 1990 the median age of all patients in the cystic fibrosis registry was 12.5 years; the median age at diagnosis was 7 months; cystic fibrosis was diagnosed in 90% of all patients by age 12 years. Meconium ileus at birth was reported for 16% of all patients with a new diagnosis in 1990. Median survival age doubled between 1969 and 1990, from 14 to 28 years. Female patients consistently had a lower median survival age than male patients (25 vs 30 years in 1990). The most frequently reported respiratory pathogen was Pseudomonas aeruginosa , cultured in specimens from 61% of all patients, ranging from 21% of those less than 1 year of age to more than 80% of those aged 26 years or older. Overall, patients with cystic fibrosis are living much longer than in the past but still have chronic pulmonary infections and other medical complications related to their disease, including diabetes, intestinal obstruction, cirrhosis, hemoptysis, and pneumothorax.
Efficient Use of Electric Power in Production Operations

Inefficient electric power utilization systems can account for as much as 50% of the energy consumed in petroleum production operations. The majority of these losses occur in electric motors or in the distribution systems supplying them. Voltage adjustments, motor control method modifications, and other inexpensive solutions can cut losses and power costs by 5 to 10%. More extensive power system modifications also can be justified occasionally.