Miracle-dz/UniFAR-FTUs huggingface dataset:
Relative Yoneda Cohomology for Operator Spaces

Abstract We provide two alternate presentations of the completely bounded Hochschild cohomology. One as a relative Yoneda cohomology, i.e., as equivalence classes of n -resolutions which are relatively split, and the second as a derived functor. The first presentation makes clear the importance of certain relative notions of injectivity, projectivity and amenability which we introduce and study. We prove that every von Neumann algebra is relatively injective as a bimodule over itself and consequently, H n cb ( M , M )=0 for any von Neumann algebra M . A result obtained earlier by Christensen and Sinclair. We prove that the relatively amenable C *-algebras are precisely the nuclear C *-algebras, and hence exactly those which are amenable as Banach algebras. In a similar vein we prove that the only relatively projective C *-algebras are finite dimensional. This result implies that the only C *-algebras that are projective as Banach algebras are finite dimensional, a result first obtained by Selivanov and Helemskii. In a slightly different direction we prove that B ( H ) viewed as a bimodule over the disk algebra with the left action given by multiplication by a coisometry and the right action given by multiplication by an isometry is an injective module. This result is in some sense a generalization of the Sz. -Nagy-Foias commutant lifting theorem or of the hypoprojectivity introduced by Douglas and the author.
Microphysics of Raindrop Size Spectra: Tropical Continental and Maritime Storms

Abstract This work uses raindrop size spectra measured at the surface in tropical continental storms to determine the associated parameters of the best-fit gamma distributions. The physical processes responsible for those parameters and their relations to the measurable radar reflectivity Z and differential reflectivity ZDR are then explored. So too are their relations to quantitative measurements of rain. Comparison is then made with corresponding features previously reported in tropical maritime regimes. The storms observed in Brazil and Arecibo, Puerto Rico, have been divided into convective (C), transition (T), and stratiform (S) segments. The raindrop size distribution (DSD) parameters are clearly defined on a gamma parameter diagram (GPD) that shows 1) how median volume drop size D0 increases from S to T to C segments of the rain while 2) the range of the spectrum breadth parameter μ increases, and the range of the slope parameter Λ decreases in the same sequence of S to C. Drop growth occurs predom.
On 4-dimensional $s$-cobordisms

The idea that topological problems can be converted into questions of algebra and homotopy theory underlies much of modern higher-dimensional topology of manifolds. The s-cobordism theorem, also called the BardenMazur-Stallings theorem constitutes one of the basic building blocks of this approach. Let W be a compact (n + l)-manifold with boundary the disjoint union of manifolds M o and Mv Then this theorem asserts that for n > 5, W is diffeomorphic, piecewise linearly homeomorphic, or homeomorphic, depending on the category, to a product Mo X [0,1], if and only if W has the homotopy type of this product and a certain algebraic invariant τ(W, Mo) e Wh(πλW\ the Whitehead torsion, vanishes. (See [12], [9] and [11] for the topological case.) This result, whose simply-connected version πλW = {e} is just Smale's Λ-cobordism theorem, at least provides a direction of attack in the attempt to decide when two homotopy equivalent manifolds M o and Mx are diffeomorphic—try to construct W or to measure the obstruction to doing so. Moreover, Freedman demonstrated that this s-cobordism theorem is valid for W a topological five-dimensional s-cobordism with fundamental group not too large, e.g. finite or polycyclic; i.e., he showed that such a five-dimensional W is homeomorphic to Mo X [0,1] under the same hypothesis on the vanishing of the Whitehead torsion. This paper provides a family of orientable counterexamples to the scobordism theorem in dimension four. (It seems to have been fairly widely understood (cf. [14]) that the realization of a certain non-orientable, nonsmoothable normal invariant yields a nonorientable (and nonsmoothable) example. ) Let Qr be the quaternion group of order 2 r + 1 ; Qr = {y* Ay = * 2
Unravelling the relationship between plant diversity and vegetation structural complexity: A review and theoretical framework

Vegetation structural complexity (VSC)—the three‐dimensional distribution of plants within an ecosystem—is an important ecological trait. To date, research has focused primarily on the effects of VSC on ecological patterns and processes, but comparatively little is known about what drives variation in VSC. Recent advances in active remote sensing technology, particularly light detection and ranging and radio detection and ranging, have allowed the measurement of VSC at unprecedented spatial scales and resolutions. Out of this and earlier work has emerged evidence that VSC is typically associated with greater ecosystem functioning (especially microclimate regulation, productivity, faunal diversity and habitat provisioning), making restoration of vegetation complexity a potentially powerful restoration tool. Recent studies of VSC across natural and experimental gradients of plant diversity have also revealed that more diverse plant communities tend to be more structurally complex. However, the shape and generality of this relationship—and the mechanism(s) by which phytodiversity might contribute to structural complexity—remain poorly understood. Here, we review how active remote sensing has facilitated recent VSC research and shaped our understanding of the relationship between vegetation complexity and ecosystem function. We then present a theoretical framework for the relationship between phytodiversity and VSC based on classic biodiversity‐ecosystem functioning principles. Finally, we evaluate the evidence for the notion that diverse plant assemblages tend to be more structurally complex and explore the shape of the relationship between phytodiversity and VSC using data from 13 recent remote sensing studies. Synthesis. The relationship between phytodiversity and VSC appears to be almost universally positive. Preliminary evidence further suggests that the most common relationships between phytodiversity and VSC are linear or saturating, indicating that the extent of functional redundancy between species varies across plant communities and ecosystems. In contrast, we find little evidence for exponential or negative relationships between plant diversity and VSC, suggesting that even modest increases in plant diversity could markedly increase structural complexity. Additional investigations of phytodiversity‐VSC relationships are necessary to establish whether the observed positive relationships are causal (and, if so, in which direction) and to clarify the potential impact of plant community restoration on structural complexity and broader ecosystem function.
A coherent maximum likelihood head position estimator for PERM disk drives

A coherent digital maximum-likelihood (ML) head position estimator was proposed and examined for sampled-servo magnetic disk drives. Estimating the ML head position is obtained through four ML amplitude estimators of each servo mark readback pulse. When compared to a conventional analog integration detector about 1.7 dB improvement in position estimation accuracy was obtained. To generate a servo clock for coherent estimation, an ML phase estimating digital phase-locked loop (DPLL) was also developed. Since five inner product operations for amplitude and phase estimation are performed by a time-shared multiplier-accumulator, this ML head position estimator is applicable for use in small scale hardware and adaptable to ICs.
Growth of Zea mays in response to artificial inoculation with endophytic Beauveria bassiana compared to Trichoderma sp. “atroviride B”

ABSTRACT Demand for sustainable crop production is putting pressure on growers to improve yield while using environmentally friendly solutions. Recently, entomopathogenic fungi have been reported to promote plant growth under certain conditions; however, colonisation of plants as endophytes may be inconsistent or persistence within plant tissues brief. We studied the effects of inoculating three Beauveria bassiana isolates in comparison with a known plant-growth-promoting isolate of Trichoderma sp. “atroviride B” as a positive control, on the growth of maize (Zea mays L.). We tested the plant response by measuring multiple parameters including biomass, length, chlorophyll content and root architecture following inoculation, to identify even subtle plant growth effects. Fungal isolates were inoculated by inserting hyphae through a small wound made in the stem of emerging seedlings, a technique that has not been previously used for B. bassiana. Results showed neutral effects on biomass, but plants exhibited root architecture changes because of inoculation with B. bassiana isolate (FRh2), which increased fine root length and because of T. sp. “atroviride B” which increased larger diameter root length. A higher chlorophyll content was observed for plants inoculated with B. bassiana isolate (J18), although this did not correlate with biomass differences. The inoculation technique enabled the comparison of systemic effects to the plants and may have affected subtle but important root-trait modifications. Changes to root architecture can impact resource acquisition in plants, therefore this study highlights the importance of measuring various physiological changes in the plant host when assessing for potential growth effects.
Sub-millimetre spectroscopy of Saturn’s trace gases from Herschel/SPIRE

Aims: We provide an extensive new sub-millimetre survey of the trace gas composition of Saturn's atmosphere using the broad spectral range (15-51 cm-1) and high spectral resolution (0.048 cm-1) offered by Fourier transform spectroscopy by the Herschel/SPIRE instrument (Spectral and Photometric Imaging REceiver). Observations were acquired in June 2010, shortly after equinox, with negligible contribution from Saturn's ring emission. Methods: Tropospheric temperatures and the vertical distributions of phosphine and ammonia are derived using an optimal estimation retrieval algorithm to reproduce the sub-millimetre data. The abundance of methane, water and upper limits on a range of different species are estimated using a line-by-line forward model. Results: Saturn's disc-averaged temperature profile is found to be quasi-isothermal between 60 and 300 mbar, with uncertainties of 7 K due to the absolute calibration of SPIRE. Modelling of PH3 rotational lines confirms the vertical profile derived in previous studies and shows that negligible PH3 is present above the 10- to 20-mbar level. The upper tropospheric abundance of NH3 appears to follow a vapour pressure distribution throughout the region of sensitivity in the SPIRE data, but the degree of saturation is highly uncertain. The tropospheric CH4 abundance and Saturn's bulk C/H ratio are consistent with Cassini studies. We improve the upper limits on several species (H2S, HCN, HCP and HI); provide the first observational constraints on others (SO2, CS, methanol, formaldehyde, CH3Cl); and confirm previous upper limits on HF, HCl and HBr. Stratospheric emission from H2O is suggested at 36.6 and 38.8 cm-1 with a 1σ significance level, and these lines are used to derive mole fractions and column abundances consistent with ISO and SWAS estimations a decade earlier.
On local boundary-layer receptivity to vortical disturbances in the free stream

Prompted by the recent experiments of Dietz (1999) on boundary-layer receptivity due to a local roughness interacting with a vortical disturbance in the free stream, this paper undertakes to present a second-order asymptotic theory based on the tripledeck formulation. The asymptotic approach allows us to treat vortical perturbations with a fairly general vertical distribution, and confirms Dietz's conclusion that for the convecting periodic wake in his experiments, the receptivity is independent of its vertical structure and can be fully characterized by its slip velocity at the edge of the boundary layer. As in the case of distributed vortical receptivity, dominant interactions that generate Tollmien–Schlichting waves take place in the upper deck as well as in the so-called edge layer centred at the outer reach of the boundary layer. The initial amplitude of the excited Tollmien–Schlichting wave is determined to O(R−1/8) accuracy, where R is the global Reynolds number. An appropriate superposition formula is derived for the case of multiple roughness elements. A comprehensive comparison is made with Dietz's experimental data, and an excellent quantitative agreement has been found for the first time, thereby resolving some uncertainties about this receptivity mechanism.
High-Reynolds-number simulation of turbulent mixing

A brief report is given of a new 20483 direct numerical simulation of the mixing of passive scalars with uniform mean gradients in forced, stationary isotropic turbulence. The Taylor-scale Reynolds number is close to 700 and Schmidt numbers of 1 and 1∕8 are considered. The data provide the most convincing evidence to date for the inertial-convective scaling. Significant departures from small-scale isotropy are sustained in conventional measures. Subject to some stringent resolution requirements, the data suggest that commonly observed differences between the intermittency of energy and scalar dissipation rates may in part be a finite-Reynolds-number effect.
3-D dynamic rupture simulations by a finite volume method

SUMMARY Dynamic rupture of a 3-D spontaneous crack of arbitrary shape is investigated using a finite volume (FV) approach. The full domain is decomposed in tetrahedra whereas the surface, on which the rupture takes place, is discretized with triangles that are faces of tetrahedra. First of all, the elastodynamic equations are described into a pseudo-conservative form for an easy application of the FV discretization. Explicit boundary conditions are given using criteria based on the conservation of discrete energy through the crack surface. Using a stress-threshold criterion, these conditions specify fluxes through those triangles that have suffered rupture. On these broken surfaces, stress follows a linear slip-weakening law, although other friction laws can be implemented. For The Problem Version 3 of the dynamic-rupture code verification exercise conducted by the SCEC/USGS, numerical solutions on a planar fault exhibit a very high convergence rate and are in good agreement with the reference one provided by a finite difference (FD) technique. For a non-planar fault of parabolic shape, numerical solutions agree satisfactorily well with those obtained with a semi-analytical boundary integral method in terms of shear stress amplitudes, stopping phases arrival times and stress overshoots. Differences between solutions are attributed to the low-order interpolation of the FV approach, whose results are particularly sensitive to the mesh regularity (structured/unstructured). We expect this method, which is well adapted for multiprocessor parallel computing, to be competitive with others for solving large scale dynamic ruptures scenarios of seismic sources in the near future.
Selection of Mixed Copula Model via Penalized Likelihood

A fundamental issue of applying a copula method in applications is how to choose an appropriate copula function for a given problem. In this article we address this issue by proposing a new copula selection approach via penalized likelihood plus a shrinkage operator. The proposed method selects an appropriate copula function and estimates the related parameters simultaneously. We establish the asymptotic properties of the proposed penalized likelihood estimator, including the rate of convergence and asymptotic normality and abnormality. Particularly, when the true coefficient parameters may be on the boundary of the parameter space and the dependence parameters are in an unidentified subset of the parameter space, we show that the limiting distribution for boundary parameter estimator is half-normal and the penalized likelihood estimator for unidentified parameter converges to an arbitrary value. Finally, Monte Carlo simulation studies are carried out to illustrate the finite sample performance of the proposed approach and the proposed method is used to investigate the correlation structure and comovement of financial stock markets.
The formation mechanism of 360° domain walls in exchange-biased polycrystalline ferromagnetic films

The formation mechanism of 360° domain walls (360DW) created in an exchange-biased bilayer of Co65.5Fe14. 5B20/Ir22Mn78 is described. The structural and magnetic properties are experimentally characterized and incorporated into a micromagnetic model of exchange-bias for granular anti-ferromagnetic films. This model is used to study and explain the formation mechanism of 360DWs in the ferromagnetic layer, which occur due to interface coupling to the antiferromagnetic layer. The validity of the resulting calculated magnetization maps are examined by comparing simulated and experimental Fresnel-contrast images of the bilayer. Energy barrier simulations are used to explain the dependence of the areal size and spatial frequency of the 360DW on the anisotropy energy of the anti-ferromagnetic layer. These calculations also show how such structures can form at room temperature at relatively low applied magnetic fields. Calculations based on this model are in agreement with imaging using Lorentz transmission electr.
Critical Behavior at the SmC*α−SmC* Phase Transition Studied by High Sensitivity DSC

Calorimetric measurements have been done to investigate the smectic-C*α(SmC*α)- smectic-C*(SmC*) transition using high sensitivity differential scanning calorimetry. It was found that the SmC*α−SmC* transition for a liquid crystalline compound 11OHFBBB1M7 shows a first-order transition with a clear thermal hysteresis while other two compounds, LN36 and 12OTBBB1M7, exhibit continuous behaviors which support the existence of the critical point and also the slow relaxation dynamics encountered with the change in the helical pitch.
The bipolar molecular outflow of V645 Cygni

A map is presented of the CO J = 3-2 line emission from the cloud associated with V645 Cygni. Line wings extending to 15 km/s on either side of the central velocity can be attributed to a bipolar outflow over a region 1 arcmin in angular extent. The redshifted and blueshifted emission peaks are separated by 20 arcsecs along an axis that is approximately perpendicular to the polarization vector of the visible light. The outflow is of relatively low velocity, low mass, and low mechanical luminosity. 32 refs.
Spectral properties of asteroids in cometary orbits

Aims. In this paper we analyze the spectra of a sample of asteroids in cometary orbits (ACOs) in order to understand the relationship between them, the Jupiter family comets (JFCs), and the outer main belt populations, such as Hilda, Trojan and Cybele asteroids. Methods. We obtained visible (0.55−0.90 µm) and/or near-infrared (0.8−2.3 µm) spectra of 24 ACOs using 3 telescopes at the "Roque de los Muchachos" Observatory (La Palma, Spain). Using this data, we derived the taxonomic classification of the asteroids. As most ACOs present featureless spectra (B-, C-, P-, D-type) we also derived their spectral gradient (S � ). Considering also published spectra of ACOs we correlated Swith orbital and dynamical parameters and obtained the cumulative distribution of S � , and compare it with that of other related populations. Results. We present visible and/or near infrared spectra of 24 ACOs, most of them (21) presenting featureless spectra. After including the spectra of other ACOs already published, we analyzed a total of 41 objects, 34 of them having featureless spectra like the spectra of comet nuclei and outer main-belt asteroids. We also noticed a significant difference in the taxonomic distribution of the ACOs in Near-Earth orbits (q 1.3 AU), indicative of different source/transport mechanisms. About 35% of the ACOs in the NEO population analyzed have spectra that present the typical silicate absorption bands at 1 and 2 µ m( S- and V-type), while only 1 of the 24 ACOs in the non-NEO population (about 4%) is S-type and the other 23 have a featureless spectrum. Thus the NEO sub-population of ACOs is composed of a significant fraction of asteroids scattered from the inner main-belt. We didn't find any subtle features in the 0.5−2.0 µm spectral region of featureless ACOs that can be used to discriminate wheather an ACO comes from a cometary or an asteroidal origin. The analysis of the spectral gradient shows that ACOs present an interesting, and significant, anti-correlation between the Tisserand parameter and the "spectral gradient", meaning that the reddest objects have the lower Tisserand parameter (i.e., higher chance of a cometary origin). Finally, we obtained the Scumulative distribution for ACOs. This distribution is "bluer" than that of comet nuclei, Damocloids and outer main-belt population of asteroids, indicative of a significant "contamination" of asteroids scattered from the inner main-belt.
Theoretical and experimental study of laser beam propagation in capillary tubes for non-symmetrical coupling conditions

A non-symmetrical theoretical model is used to describe the propagation of laser beams in dielectric capillary waveguides under non-ideal coupling conditions. The displacement of the laser beam focusing point from the capillary axis, the deviation of the transverse energy distribution from a symmetric one, and an angle of incidence different from zero modify, through the excitation and beating of several modes, the energy repartition during the propagation in the waveguides. The results of modeling are in very good agreement with experimental results, obtained with a low-intensity laser beam on a test bench, where good control of the laser energy distribution in the focal plane, the focusing point position, and the angle of incidence was achieved.
Asymptotic Expansion of the Bardeen-Cooper-Schrieffer Partition Function by Means of the Functional Method,

The canonical operator exp [−β(H − μN)] associated with the Bardeen‐Cooper‐Schrieffer (BCS) model Hamiltonian of superconductivity is represented as a functional integral by the use of Feynman's ordering parameter. General properties of the partition function in this representation are discussed. Taking the inverse volume of the system as an expansion parameter, it is possible to calculate the thermodynamic potential including terms independent of the volume. This yields a new proof that the BCS variational value is asymptotically exact. The behavior of the canonical operator for large volume is described and related to the state of free quasiparticles. A study of the terms of the thermodynamic potential which are of smaller order in the volume in the low‐temperature limit, shows that the ground state energy is nondegenerate and belongs to a number eigenstate.