Miracle-dz/UniFAR-FTUs huggingface dataset:
Ambient Noise Rayleigh Wave Shallow Tomography in the Tehran Region, Central Alborz, Iran

The Tehran region is one of the most densely concentrated areas of seismic activity in northern Iran. This region is dominated by the central Alborz Mountains belt and a large composite cone, the Damavand volcano. Located in the foothills of the Alborz Mountains, the city of Tehran, with a population of ∼15 million, is subject to high seismic risk (Jackson 2006; Berberian 2005). It is also surrounded by many active faults that have caused destructive earthquakes in the past (Berberian and Yeats 2001). Recent seismicity studies ( e.g. , Mottaghi et al. 2010) indicate that this region is under t|he threat of some major and yet unresolved active faults. Strong ground motion due to amplification of seismic energy by shallow velocity structure can be responsible for serious property damage (German and Beroza 2008). In order to accurately predict ground motion through waveform modeling, it is necessary to accurately image the shallow crustal seismic velocity. The local tomographic images available in the Tehran area come from body-wave earthquake tomography ( e.g. , Mostafanejad et al. 2011) and do not allow precise control of the near-surface (depth < 5 km) velocity structure. Furthermore, this model is affected by a variety of factors such as the effect of uneven source (or station) distribution and potential errors in identifiable seismic sources. We address these limitations by using the information extracted from ambient seismic noise. The present study uses continuous data recorded at a variety of sensors to investigate shallow crustal structure surrounding Tehran. We extract inter-station Green’s functions (GFs), with Rayleigh waves as the largest component, from beams of ambient noise cross-correlations at stations in and around the city of Tehran. We first estimate group velocity dispersion curves in the period band between 2 and 4 sec for each station-pair to invert for the 2D …
Precision measurement of $CP$ violation in $B_s^0 \to J/\psi K^+K^-$ decays

The time-dependent $CP$ asymmetry in $B_s^0 \to J/\psi K^+K^-$ decays is measured using $pp$ collision data, corresponding to an integrated luminosity of $3.0$fb$^{-1}$, collected with the LHCb detector at centre-of-mass energies of $7$ and $8$TeV. In a sample of 96 000 $B_s^0 \to J/\psi K^+K^-$ decays, the $CP$-violating phase $\phi_s$ is measured, as well as the decay widths $\Gamma_{L}$ and $\Gamma_{H}$ of the light and heavy mass eigenstates of the $B_s^0-\bar{B}_s^0$ system. The values obtained are $\phi_s = -0.058 \pm 0.049 \pm 0.006$ rad, $\Gamma_s \equiv (\Gamma_{L}+\Gamma_{H})/2 = 0.6603 \pm 0.0027 \pm 0.0015$ps$^{-1}$, and$\Delta\Gamma_s \equiv \Gamma_{L} - \Gamma_{H} = 0.0805 \pm 0.0091 \pm 0.0032$ps$^{-1}$, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements of those quantities to date. A combined analysis with $B_s^{0} \to J/\psi \pi^+\pi^-$ decays gives $\phi_s = -0.010 \pm 0.039 $rad. All measurements are in agreement with the Standard Model predictions. For the first time the phase $\phi_s$ is measured independently for each polarisation state of the $K^+K^- $ system and shows no evidence for polarisation dependence.
Solution to the volume problem in serpentinization

Kernel pattern consists of a rim of completely serpentinized peridotite surrounding a core of partly serpentinized, or unserpentinized, peridotite. It is found adjacent to shear zones in some serpentinites. Kernels are commonly rectangular, with length/width ratios of 1 to 3. The boundary between the completely serpentinized rim and the unserpentinized core is commonly cut at a high angle by cross-fractures. The cross-fractures, which contain either picrolite or chrysotile asbestos, taper out in the core and widen in the rim. They are almost always perpendicular to the core-rim boundary and point into the core of the kernel. In this sense they are radially distributed in the rim. The kernel pattern can be observed in thin section, in outcrop, and on the megascopic scale of tens of metres. Cross-fractures represent expansion fractures in serpentinite in the rim of the kernel caused by an increase in volume acompanying serpentinization of the peridotite in the core of the kernel. As the serpentinization front penetrates into the kernel, the serpentinized peridotite expands. However, the serpentinite in the rim cannot expand and must fracture to accommodate the increase in volume. As serpentinization proceeds, more expansion occurs, extending the fractures farther into the core and requiring the fractures in the existing serpentinite to widen. These fractures are subsequently filled by serpentine minerals. The resulting pattern consists of a rim of serpentinite, cut by serpentine veins, that surrounds a core of peridotite. Measured densities of cross-fractures in the rims of kernels are consistent with those expected from the magnitude of the volume change accompanying serpentinization of peridotite.
Hierarchical modeling of polystyrene melts: From soft blobs to atomistic resolution.

We demonstrate that hierarchical backmapping strategies incorporating generic blob-based models can equilibrate melts of high-molecular-weight polymers, described with chemically specific, atomistic, models. The central idea behind these strategies, is first to represent polymers by chains of large soft blobs (spheres) and efficiently equilibrate the melt on mesoscopic scale. Then, the degrees of freedom of more detailed models are reinserted step by step. The procedure terminates when the atomistic description is reached. Reinsertions are feasible computationally because the fine-grained melt must be re-equilibrated only locally. To develop the method, we choose a polymer with sufficient complexity. We consider polystyrene (PS), characterized by stereochemistry and bulky side groups. Our backmapping strategy bridges mesoscopic and atomistic scales by incorporating a blob-based, a moderately CG, and a united-atom model of PS. We demonstrate that the generic blob-based model can be parameterized to reproduce the mesoscale properties of a specific polymer -- here PS. The moderately CG model captures stereochemistry. To perform backmapping we improve and adjust several fine-graining techniques. We prove equilibration of backmapped PS melts by comparing their structural and conformational properties with reference data from smaller systems, equilibrated with less efficient methods.
Application of the notion of $\Phi$-object to the study of p-class groups and p-ramified torsion groups of abelian extensions

We revisit, in an elementary way, the classical statement of various ``Main Conjectures'' for $p$-class groups $\mathcal{H}_K$ and $p$-ramified torsion groups $\mathcal{T}_K$ of abelian fields $K$, in the non semi-simple case $p \mid [K : \mathbb{Q}]$. The classical ``algebraic'' definition of the $p$-adic isotopic components, $\mathcal{H}^{\rm alg}{K,\varphi}$, used in the literature, is inappropriate with respect to analytical formulas. For that reason we have introduced, in the 1970's, an ``arithmetic'' definition, $\mathcal{H}^{\rm ar}{K,\varphi}$, in perfect correspondence with all analytical formulas and giving a natural ``Main Conjecture'', still unproved for real fields in the non semi-simple case. The two notions coincide for relative class groups $\mathcal{H}_K^-$ and groups $\mathcal{T}_K$ since, in $p$-extensions, transfer maps are injective for these groups but not necessarily for real class groups. Numerical evidence of the gap between the two notions is given (Examples A.2.2, A.2.3) and PARI calculations corroborate that the true Real Main Conjecture for $K$ writes on the form $\# \mathcal{H}^{\rm ar}_{K,\varphi} = \# (\mathcal{E}_K / \hat{\mathcal{E}}_K \, \mathcal{F}_{\! K})_{\varphi}$, in terms of units $\mathcal{E}_K$, $\hat{\mathcal{E}}_K$ (units of the strict subfields) and $\mathcal{F}_K$ (Leopoldt's cyclotomic units). A recent approach, conjecturing the capitulation of $\mathcal{H}_K$ in some auxiliary cyclotomic extensions $K(\mu_\ell^{})$, proves the difficult real case.
Experimental investigation of the velocity of a sand cloud blowing over a sandy surface

The velocity of a wind‐blown sand cloud is important for studying its kinetic energy, related erosion, and control measures. PDA (particle dynamics analyser) measurement technology is used in a wind tunnel to study the probability distribution of particle velocity, variations with height of the mean velocity and particle turbulence in a sand cloud blowing over a sandy surface. The results suggest that the probability distribution of the particle velocity in a blowing sand cloud is stochastic. The probability distribution of the downwind velocity complies with a Gaussian function, while that of the vertical velocity is greatly complicated by grain impact with the bed and particle–particle collisions in the air. The probability distribution of the vertical velocity of ﬁne particles (0·1–0·3 mm sands) can be expressed as a Lorentzian function while that of coarse particles (0·3–0·6 mm sands) cannot be expressed by a simple distribution function. The mean downwind velocity is generally one or two orders greater than the mean vertical velocity, but the particle turbulence in the vertical direction is at least two orders greater than that in the downwind direction. In general, the mean downwind velocity increases with height and free‐stream wind velocity, but decreases with grain size. The variation with height of the mean downwind velocity can be expressed by a power function. The particle turbulence of a blowing sand cloud in the downwind direction decreases with height. The variations with height of the mean velocity and particle turbulence in the vertical direction are very complex. It can be concluded that the velocity of a sand cloud blowing over a sandy surface is mainly inﬂuenced by wind velocity, grain impact with the bed and particle–particle collisions in the air. Wind velocity is the primary factor inﬂuencing the downwind velocity of a blowing sand cloud, while the grain impact with the bed and particle–particle collisions in the air are the primary factors responsible for the vertical velocity. Copyright © 2004 John Wiley & Sons, Ltd.
A test of real‐time prediction of magnetic cloud topology and geomagnetic storm occurrence from solar signatures

On the basis of the location, orientation, and surrounding magnetic field configuration of an erupting filament observed on September 27, 1997, an Earth-encounter with a magnetic cloud having specific topological properties and an ensuing geomagnetic storm were predicted for September 30, assuming an average Sun-Earth transit time. A subsequent comparison with solar wind and geomagnetic data surrounding September 30 yielded a mixed level of success. Although a geomagnetic storm occurred on October 1, ironically, the strong southward magnetic field responsible for it was not encountered at the leading edge of the cloud, as predicted, but rather in the preceding sheath. In retrospect, the most likely sources of the southward field in the sheath were either a preceding CME or magnetic flux from high in the corona, not draped or turbulent flux from the ambient solar wind as is often supposed. With the aid of a flux rope model, we show that the elevation and polarity of the cloud axis and the chirality of the cloud were predicted correctly but that the trajectory of the spacecraft (and Earth) through what was deduced to be the leg of a flux rope loop precluded encounter with its leading southward field. The storm began with a sudden commencement near 0100 UT on October 1, corresponding to passage of a shock-like discontinuity, and the Dst storm index reached a minimum of −108 nT 14 hours later at 1500 UT. The leading edge of the cloud, however, coincident with the onset of counterstreaming electrons confirming its identification, was not encountered until 1700 UT. The disagreement between the predicted and actual arrival time reflects not only the lack of speed prediction capabilities but also the inability to predict whether encounter will be head-on with the apex of a flux rope loop or, as deduced in this case, passage through one of its legs.
Capturing LiDAR‐Derived Hydrologic Spatial Parameters to Evaluate Playa Wetlands

The digital elevation model data from traditional stereo photogrammetric methods are inadequate in providing accurate vertical parameters to feed hydrologic models for low‐lying, extremely flat areas. High‐resolution light detection and ranging (LiDAR) data provide the robust capability of capturing small variations in low‐relief playa wetlands. The Rainwater Basin in south‐central Nebraska includes a complex of seasonally shallow playa wetlands that attract millions of migratory waterfowl every spring and fall. This research focuses on the development of a procedure with applicable protocols to produce LiDAR‐derived three‐dimensional wetland maps and to extract the critical surface parameters (i.e., watershed boundaries, flow direction, flow accumulation, and drainage lines) for playa wetlands. The topo‐hydrologic conditions of playa wetlands were evaluated at the watershed level. The results show that in the Rainwater Basin, 70.7% of the historic hydric soil footprints identified in the Soil Survey Geographic (SSURGO) database were not functioning as topographically depressional wetlands. This finding was confirmed by a recent five‐year Annual Habit Survey showing that 69.8% of the historic hydric soil footprints did not function during the spring migratory bird seasons between 2004 and 2009. The majority of playa wetlands' topographic conditions have been substantially changed and the SSURGO data cannot fully reflect current topographic reality in the Rainwater Basin.
Proper Motions of New Dust in the Colliding Wind Binary WR 140

The eccentric W-R + O binary system WR 140 produces dust for a few months at intervals of 7.94 yr coincident with periastron passage. We present the first resolved images of this dust shell, at binary phases ϕ ~ 0.039 and ~0.055, using aperture masking techniques on the Keck I telescope to achieve diffraction-limited resolution. Proper motions of approximately 1.1 mas per day were detected, implying a distance ≲1.5 kpc from the known wind speed. The dust plume observed is not as simple as the "pinwheel" nebulae seen around other W-R colliding wind binaries, indicating the orbital plane is highly inclined to our line of sight and/or the dust formation is very clumpy. Follow-up imaging in the mid-infrared and with adaptive optics is urgently required to track the dust motion further, necessary for unambiguously determining the orbital geometry, which we only partially constrain here. With full knowledge of the orbital elements, these infrared images can be used to reconstruct the dust distribution along the colliding wind interface, providing a unique tool for probing the postshock physical conditions of violent astrophysical flows.
Mesospheric potassium layer over the Arecibo Observatory, 18.3°N 66.75°W

A resonance lidar has made regular measurements of mesospheric potassium at the Arecibo Observatory (18.3°N, 66.75°W) since July 1999. Through July 2001 a total of 65 nights of density measurements were carried out, amounting to several nights each month over most of the period. The layer shows considerable nightly and seasonal variation: Spring and early summer nights had frequent sporadic layer activity; nightly variability in the layer width was large due to sporadic layer activity, but the seasonal variation was small; the altitude of the layer centroid was fairly constant throughout the year; and the column abundance showed semi‐annual variation. These results are compared with a similar set of potassium measurements from a mid‐latitude site, and the latitudinal implications are discussed.
Superresolution in imagery arising from observation through anisoplanatic distortion

The possibility of obtaining spatial frequency information normally excluded by an aperture has been surmised, experimentally obtained in the laboratory, and observed in processed real world imagery. This opportunity arises through the intervention of a turbulent mass between the stationary wide-area object of interest and the short exposure, imaging instrument, but the frequency information is aliased, and must be de-aliased to render it useful. We present evidence of super-resolution in real-world surveillance imagery that is processed by hierarchical registration algorithms. These algorithms have been enhanced over those we previously reported. We discuss these enhancements and give examples of the use of the algorithm to gain information about the turbulence. To further reinforce the presence of super-resolution we present two methods for creating imagery warped by Kolmogorov turbulent phase screens, so that the results can be confirmed against true images.
SN 1986E eight years after outburst: a link to SN 1957D?

We report on the optical recovery of SN~1986E 7.1 and 7.9 years after explosion. The spectra are dominated by broad H$\alpha$ and [O~I] $\lambda\lambda$6300,6364 emission lines with a minor contribution from [Ca~II] $\lambda\lambda$7291,7324 and, possibly, [Fe~II] $\lambda$7155. Compared with the spectra of the other recovered SNII, SN1986E shows strong H$\alpha$ luminosity similar to SN~1979C but, in contrast, weak [O~III] emission. So far, among classified SNe, only type II Linears have been recovered a few years past the explosion. The high optical luminosity of Linear SNII at this phase is most likely related to the interaction of the ejecta with the circumstellar wind which is also expected to produce strong radio emission. Therefore radio observations of the remnant of SN~1986E are worth attempting. The circumstellar interaction model predicts that, in the next decade, the strength of the [O~III]/H$\alpha$ emission rapidly increases and [O~III] $\lambda\lambda$4959,5007 should eventually dominate the spectrum. We observed this effect in SN~1957D 30 years after explosion which therefore may represent the normal evolution of SNII with a dense circumstellar medium. The details observed in the spectra of both SNe suggest directions for further refinement of the modelling.
Evolution of North Atlantic Water masses inferred from Labrador Sea salinity series

The Labrador Sea is the coldest and freshest basin of the North Atlantic. Winter cooling in this sea produces Labrador Sea Water. This intermediate water plays an important role in the exchange of heat, freshwater, and other substances between the atmosphere and the abyssal ocean, affecting the water masses, circulation, and, ultimately, climate of the subpolar North Atlantic basins. The subpolar gyre of the North Atlantic has exhibited large changes in temperature, salinity, and volume over the past six decades, largely in response to changing winter conditions over the Labrador Sea. The signature of these changes can be seen in the lower limb of the Meridional Overturning Circulation down into the North Atlantic tropics.
Historical wave height trends in the South and East China Seas, 1911–2010

This study reconstructs 6 hourly significant wave heights (Hs) in the South and East China Seas for the period 1871–2010, using the Twentieth Century Reanalysis ensemble of mean sea level pressure (SLP) fields and a multivariate regression model to represent the Hs-SLP relationship in each study area. The regression model was calibrated and validated using the ERA-Interim reanalysis of Hs and SLP for the period 1981–2010. These reconstructions were found to reproduce reasonably well the seasonal mean and maximum Hs climates as represented by the ERA40 and ERA-Interim wave reanalyses. For each study area, an ensemble of 56 members of 6 hourly Hs was reconstructed for each grid point. The regional mean series of the ensemble mean of the reconstructed consecutive monthly mean Hs was tested for temporal homogeneity, which identified a few discontinuities in the pre-1946 period and led to the exclusion of the reconstructed Hs for 1871–1910 from trend analysis (due to data uncertainty and inhomogeneity). Each 6 hourly Hs time series for the period 1911–2010 was homogenized for the identified discontinuities, before being used to derive annual and seasonal mean and maximum Hs for trend analysis. The trend analysis results show that, in both study areas, the 1911–2010 wave height trends are dominantly negative, with the exception that the seasonal maximum significant wave heights seem to have increased in summer and spring in the central South China Sea and in summer in the East China Sea.
An assessment of the radiative effects of anthropogenic sulfate

We use a coupled climate/chemistry model with cloud nucleation processes parameterized in terms of local aerosol number, anthropogenic sulfate mass concentration, and updraft velocity to investigate both direct and indirect anthropogenic sulfate radiative forcings. We estimate that the global direct radiative forcing is about {minus}0.4Wm{sup {minus}2} with a maximum over Europe where the strongest anthropogenic sulfur emissions occur. With different approaches for the formation of anthropogenic sulfate and its relation to aerosol size distribution, we estimate that the indirect forcing may range from {minus}0.6 to {minus}1.6Wm{sup {minus}2}. This range reduces to {minus}0.4 to {minus}1.1Wm{sup {minus}2} if a prescribed marine background particle number concentration is universally applied over the ocean. Contrary to the direct effect which is more significant over continents, the calculated maximum of indirect forcing is located over the Atlantic Ocean near the coastline of North America. Our simulations indicate that anthropogenic sulfate may result in important increases in reflected solar radiation, which would mask locally the warming from increased greenhouse gases. We also compare the simulated cloud drop effective radii with those retrieved from satellite data to validate the accuracy of our cloud drop parameterization. {copyright} 1997 American Geophysical Union
Effect of pooling samples on the efficiency of comparative studies using microarrays

MOTIVATION Many biomedical experiments are carried out by pooling individual biological samples. However, pooling samples can potentially hide biological variance and give false confidence concerning the data significance. In the context of microarray experiments for detecting differentially expressed genes, recent publications have addressed the problem of the efficiency of sample pooling, and some approximate formulas were provided for the power and sample size calculations. It is desirable to have exact formulas for these calculations and have the approximate results checked against the exact ones. We show that the difference between the approximate and the exact results can be large. RESULTS In this study, we have characterized quantitatively the effect of pooling samples on the efficiency of microarray experiments for the detection of differential gene expression between two classes. We present exact formulas for calculating the power of microarray experimental designs involving sample pooling and technical replications. The formulas can be used to determine the total number of arrays and biological subjects required in an experiment to achieve the desired power at a given significance level. The conditions under which pooled design becomes preferable to non-pooled design can then be derived given the unit cost associated with a microarray and that with a biological subject. This paper thus serves to provide guidance on sample pooling and cost-effectiveness. The formulation in this paper is outlined in the context of performing microarray comparative studies, but its applicability is not limited to microarray experiments. It is also applicable to a wide range of biomedical comparative studies where sample pooling may be involved.