Instruction: what is the prompt that generates the input?

Input: Information integration applications, such as mediators or mashups, thatrequire access to information resources currently rely on users manuallydiscovering and integrating them in the application. Manual resource discoveryis a slow process, requiring the user to sift through results obtained viakeyword-based search. Although search methods have advanced to include evidencefrom document contents, its metadata and the contents and link structure of thereferring pages, they still do not adequately cover information sources --often called ``the hidden Web''-- that dynamically generate documents inresponse to a query. The recently popular social bookmarking sites, which allowusers to annotate and share metadata about various information sources, providerich evidence for resource discovery. In this paper, we describe aprobabilistic model of the user annotation process in a social bookmarkingsystem del.icio.us. We then use the model to automatically find resourcesrelevant to a particular information domain. Our experimental results on dataobtained from \emph{del.icio.us} show this approach as a promising method forhelping automate the resource discovery task.


Instruction: what is the prompt that generates the input?

Input: We obtain constraints on possible structures of mass matrices in the quarksector by using as experimental restrictions the determined values of the quarkmasses at the $M_Z$ energy scale, the magnitudes of the quark mixing matrixelements $V_{\rm ud}$, $V_{\rm us}$, $V_{\rm cd}$, and $V_{\rm cs}$, and theJarlskog invariant $J(V)$. Different cases of specific mass matrices areexamined in detail. The quality of the fits for the Fritzsch and Stech typemass matrices is about the same with $\chi^2/{\rm dof}=4.23/3=1.41$ and$\chi^2/{\rm dof}=9.10/4=2.28$, respectively. The fit for a simplegeneralization (one extra parameter) of the Fritzsch type matrices, in thephysical basis, is much better with $\chi^2/{\rm dof}=1.89/4=0.47$. Forcomparison we also include the results using the quark masses at the 2 GeVenergy scale. The fits obtained at this energy scale are similar to that at$M_Z$ energy scale, implying that our results are unaffected by the evolutionof the quark masses from 2 to 91 GeV.


Instruction: what is the prompt that generates the input?

Input: A generalization of the usual ideles group is proposed, namely, we constructcertain adelic complexes for sheaves of $K$-groups on schemes. More generally,such complexes are defined for any abelian sheaf on a scheme. We focus on thecase when the sheaf is associated to the presheaf of a homology theory withcertain natural axioms, satisfied by $K$-theory. In this case it is proven thatthe adelic complex provides a flasque resolution for the above sheaf and thatthe natural morphism to the Gersten complex is a quasiisomorphism. The mainadvantage of the new adelic resolution is that it is contravariant andmultiplicative in contrast to the Gersten resolution. In particular, thisallows to reprove that the intersection in Chow groups coincides up to signwith the natural product in the corresponding $K$-cohomology groups. Also, weshow that the Weil pairing can be expressed as a Massey triple product in$K$-cohomology groups with certain indices.


Instruction: what is the prompt that generates the input?

Input: We here report on the multiwavelength study which led us to theidentification of X-ray source IGR J16194-2810 as a new Symbiotic X-ray Binary(SyXB), that is, a rare type of Low Mass X-ray Binary (LMXB) composed of aM-type giant and a compact object. Using the accurate X-ray position allowed bySwift/XRT data, we pinpointed the optical counterpart, a M2 III star. Besides,the combined use of the spectral information afforded by XRT and INTEGRAL/IBISshows that the 0.5-200 keV spectrum of this source can be described with anabsorbed Comptonization model, usually found in LMXBs and, in particular, inSyXBs. No long-term (days to months) periodicities are detected in the IBISdata. The time coverage afforded by XRT reveals shot-noise variability typicalof accreting Galactic X-ray sources, but is not good enough to explore thepresence of X-ray short-term (seconds to hours) oscillations in detail. Byusing the above information, we infer important parameters for this source suchas its distance (about 3.7 kpc) and X-ray luminosity (about 1.4e35 erg/s in the0.5-200 keV band), and we give a description for this system (typical of SyXBs)in which a compact object (possibly a neutron star) accretes from the wind ofits M-type giant companion. We also draw some comparisons between IGRJ16194-2810 and other sources belonging to this subclass, finding that thisobject resembles SyXBs 4U 1700+24 and 4U 1954+31.


Instruction: what is the prompt that generates the input?

Input: Since the advent of chirped pulse amplification1 the peak power of lasers hasgrown dramatically and opened the new branch of high field science, deliveringthe focused irradiance, electric fields of which drive electrons into therelativistic regime. In a plasma wake wave generated by such a laser,modulations of the electron density naturally and robustly take the shape ofparaboloidal dense shells, separated by evacuated regions, moving almost at thespeed of light. When we inject another counter-propagating laser pulse, it ispartially reflected from the shells, acting as relativistic flying(semi-transparent) mirrors, producing an extremely time-compressedfrequency-multiplied pulse which may be focused tightly to the diffractionlimit. This is as if the counterstreaming laser pulse bounces off arelativistically swung tennis racket, turning the ball of the laser photonsinto another ball of coherent X-ray photons but with a form extremelyrelativistically compressed to attosecond and zeptosecond levels. Here wereport the first demonstration of the frequency multiplication detected fromthe reflection of a weak laser pulse in the region of the wake wave generatedby the driver pulse in helium plasma. This leads to the possibility of verystrong pulse compression and extreme coherent light intensification. ThisRelativistic Tennis with photon beams is demonstrated leading to thepossibility toward reaching enormous electromagnetic field intensification andfinally approaching the Schwinger field, toward which the vacuum nonlinearlywarps and eventually breaks, producing electron-positron pairs.


Instruction: what is the prompt that generates the input?

Input: The noteworthy BaBar and Belle evidence for $D^0$-$\bar{D}^0$ mixingmotivates us to study its impact on $D^0\to K^{*\pm} K^\mp$ decays and theirCP-conjugate processes. We show that both the $D^0$-$\bar{D}^0$ mixingparameters ($x$ and $y$) and the strong phase difference between $\bar{D}^0\toK^{*\pm}K^\mp$ and $D^0\to K^{*\pm}K^\mp$ transitions ($\delta$) can bedetermined or constrained from the time-dependent measurements of these decaymodes. On the $\psi (3770)$ and $\psi (4140)$ resonances at a $\tau$-charmfactory, it is even possible to determine or constrain $x$, $y$ and $\delta$from the time-independent measurements of coherent $(D^0\bar{D}^0) \to(K^{*\pm} K^\mp)(K^{*\pm} K^\mp)$ decays. If the CP-violating phase of$D^0$-$\bar{D}^0$ mixing is significant in a scenario beyond the standardmodel, it can also be extracted from the $K^{*\pm} K^\mp$ events.


Instruction: what is the prompt that generates the input?

Input: Dynamic properties of molecular motors that fuel their motion by activelyinteracting with underlying molecular tracks are studied theoretically viadiscrete-state stochastic ``burnt-bridge'' models. The transport of theparticles is viewed as an effective diffusion along one-dimensional latticeswith periodically distributed weak links. When an unbiased random walker passesthe weak link it can be destroyed (``burned'') with probability p, providing abias in the motion of the molecular motor. A new theoretical approach thatallows one to calculate exactly all dynamic properties of motor proteins, suchas velocity and dispersion, at general conditions is presented. It is foundthat dispersion is a decreasing function of the concentration of bridges, whilethe dependence of dispersion on the burning probability is more complex. Ourcalculations also show a gap in dispersion for very low concentrations of weaklinks which indicates a dynamic phase transition between unbiased and biaseddiffusion regimes. Theoretical findings are supported by Monte Carlo computersimulations.


Instruction: what is the prompt that generates the input?

Input: On a fading channel with no channel state information at the receiver,calculating true log-likelihood ratios (LLR) is complicated. Existing workassume that the power of the additive noise is known and use the expected valueof the fading gain in a linear function of the channel output to findapproximate LLRs. In this work, we first assume that the power of the additivenoise is known and we find the optimum linear approximation of LLRs in thesense of maximum achievable transmission rate on the channel. The maximumachievable rate under this linear LLR calculation is almost equal to themaximum achievable rate under true LLR calculation. We also observe that thismethod appears to be the optimum in the sense of bit error rate performancetoo. These results are then extended to the case that the noise power isunknown at the receiver and a performance almost identical to the case that thenoise power is perfectly known is obtained.


Instruction: what is the prompt that generates the input?

Input: Many important real-world networks manifest "small-world" properties such asscale-free degree distributions, small diameters, and clustering. The mostcommon model of growth for these networks is "preferential attachment", wherenodes acquire new links with probability proportional to the number of linksthey already have. We show that preferential attachment is a special case ofthe process of molecular evolution. We present a new single-parameter model ofnetwork growth that unifies varieties of preferential attachment with thequasispecies equation (which models molecular evolution), and also with theErdos-Renyi random graph model. We suggest some properties of evolutionarymodels that might be applied to the study of networks. We also derive the formof the degree distribution resulting from our algorithm, and we show throughsimulations that the process also models aspects of network growth. Theunification allows mathematical machinery developed for evolutionary dynamicsto be applied in the study of network dynamics, and vice versa.


Instruction: what is the prompt that generates the input?

Input: The problem of finding the asymptotic behavior of the maximal density ofsphere packings in high Euclidean dimensions is one of the most fascinating andchallenging problems in discrete geometry. One century ago, Minkowski obtaineda rigorous lower bound that is controlled asymptotically by $1/2^d$, where $d$is the Euclidean space dimension. An indication of the difficulty of theproblem can be garnered from the fact that exponential improvement ofMinkowski's bound has proved to be elusive, even though existing upper boundssuggest that such improvement should be possible. Using astatistical-mechanical procedure to optimize the density associated with a"test" pair correlation function and a conjecture concerning the existence ofdisordered sphere packings [S. Torquato and F. H. Stillinger, ExperimentalMath. {\bf 15}, 307 (2006)], the putative exponential improvement was foundwith an asymptotic behavior controlled by $1/2^{(0.77865...)d}$. Using the samemethods, we investigate whether this exponential improvement can be furtherimproved by exploring other test pair correlation functions correponding todisordered packings. We demonstrate that there are simpler test functions thatlead to the same asymptotic result. More importantly, we show that there is awide class of test functions that lead to precisely the same exponentialimprovement and therefore the asymptotic form $1/2^{(0.77865...)d}$ is muchmore general than previously surmised.


Instruction: what is the prompt that generates the input?

Input: We study macroscopic quantum tunneling (MQT) in c-axis twist Josephsonjunctions made of high-T_c superconductors in order to clarify the influence ofthe anisotropic order parameter symmetry (OPS) on MQT. The dependence of theMQT rate on the twist angle $\gamma$ about the c-axis is calculated by usingthe functional integral and the bounce method. Due to the d-wave OPS, the$\gamma$ dependence of standard deviation of the switching current distributionand the crossover temperature from thermal activation to MQT are found to begiven by $\cos2\gamma$ and $\sqrt{\cos2\gamma}$, respectively. We also showthat a dissipative effect resulting from the nodal quasiparticle excitation onMQT is negligibly small, which is consistent with recent MQT experiments usingBi${}_2$Sr${}_2$CaCu${}_2$O${}_{8 + \delta}$ intrinsic junctions. These resultsindicate that MQT in c-axis twist junctions becomes a useful experimental toolfor testing the OPS of high-T_c materials at low temperature, and suggest highpotential of such junctions for qubit applications.


Instruction: what is the prompt that generates the input?

Input: In the semi-classical treatment, i.e. in a classical black hole geometry,Hawking quanta emerge from trans-Planckian configurations because of scaleinvariance. There is indeed no scale to stop the blue-shifting effectencountered in the backward propagation towards the event horizon. On thecontrary, when taking into account the gravitational interactions neglected inthe semi-classical treatment, a UV scale stopping the blue-shift could bedynamically engendered. To show that this is the case, we use anon-perturbative treatment based on the large-N limit, where $N$ is the numberof matter fields. In this limit, the semi-classical treatment is the leadingcontribution. Non-linear gravitational effects appear in the next orders and inthe first of these, the effects are governed by the two-point correlationfunction of the energy-momentum tensor evaluated in the vacuum. Taking thiscorrelator into account, backward propagated modes are dissipated at a distancefrom the horizon $\propto G\kappa$ when measured in a freely falling frame.($G$ is Newton's constant and $\kappa$ the surface gravity.) This result can bealso obtained by considering light propagation in a stochastic ensemble ofmetrics whose fluctuations are determined by the above correlator.


Instruction: what is the prompt that generates the input?

Input: We propose an extension of the principle of virtual work of mechanics torandom dynamics of mechanical systems. The total virtual work of theinteracting forces and inertial forces on every particle of the system iscalculated by considering the motion of each particle. Then according to theprinciple of Lagrange-d'Alembert for dynamical equilibrium, the vanishingensemble average of the virtual work gives rise to the thermodynamicequilibrium state with maximization of thermodynamic entropy. This approachestablishes a close relationship between the maximum entropy approach forstatistical mechanics and a fundamental principle of mechanics, and constitutesan attempt to give the maximum entropy approach, considered by many as only aninference principle based on the subjectivity of probability and entropy, thestatus of fundamental physics law.


Instruction: what is the prompt that generates the input?

Input: With an automatic image analysis device, we studied the temporal distributionof the locomotor activity of E. orientalis and E. vuilleti during 24 h, andover several days to know whether the activity rhythms of these two Eupelmidaeplay a role in their competitive interactions. The analysis of locomotoractivity rhythms of E. orientalis and E. vuilleti shows that the locomotoractivity of both species presents daily cyclic variations. These two Eupelmidaehave similar activity rhythms. Displacements of these parasitoids essentiallytake place during the photophase. But the activity of E. vuilleti is earlier,because the individuals of this species start their activity on average 4 to 5h earlier than those of E. orientalis. E. vuilleti begins its displacementsseveral hours before the onset of lighting, whereas E. orientalis is activeonly in the presence of the light. This shift of starting activity is thus afactor allowing these concurrent species to minimize their interactions duringthe cohabitation period in traditional granaries after the harvests of cowpea.


Instruction: what is the prompt that generates the input?

Input: It has been demonstrated that quantum vacuum energy gravitates according tothe equivalence principle, at least for the finite Casimir energies associatedwith perfectly conducting parallel plates. We here add further support to thisconclusion by considering parallel semitransparent plates, that is,delta-function potentials, acting on a massless scalar field, in a spacetimedefined by Rindler coordinates (tau,x,y,xi). Fixed xi in such a spacetimerepresents uniform acceleration. We calculate the force on systems consistingof one or two such plates at fixed values of xi. In the limit of large Rindlercoordinate xi (small acceleration), we recover (via the equivalence principle)the situation of weak gravity, and find that the gravitational force on thesystem is just Mg, where g is the gravitational acceleration and M is the totalmass of the system, consisting of the mass of the plates renormalized by theCasimir energy of each plate separately, plus the energy of the Casimirinteraction between the plates. This reproduces the previous result in thelimit as the coupling to the delta-function potential approaches infinity.


Instruction: what is the prompt that generates the input?

Input: This paper extends earlier work on quantum theory representations of naturalnumbers N, integers I, and rational numbers Ra to describe a space of theserepresentations and transformations on the space. The space is parameterized by4-tuple points in a parameter set. Each point, (k,m,h,g), labels a specificrepresentation of X = N, I, Ra as a Fock space F^{X}_{k,m,h} of states offinite length strings of qukits q and a string state basis B^{X}_{k,m,h,g}. Thepair (m,h) locates the q string in a square integer lattice I \times I, k isthe q base, and the function g fixes the gauge or basis states for each q. Mapson the parameter set induce transformations on on the representation space.There are two shifts, a base change operator W_{k',k}, and a basis or gaugetransformation function U_{k}. The invariance of the axioms and theorems for N,I, and Ra under any transformation is discussed along with the dependence ofthe properties of W_{k',k} on the prime factors of k' and k. This suggests thatone consider prime number q's, q_{2}, q_{3}, q_{5}, etc. as elementary and thebase k q's as composites of the prime number q's.


Instruction: what is the prompt that generates the input?

Input: We use a N--body/hydrodynamic simulation to forecast the future encounterbetween the Milky Way and the Andromeda galaxies, given current observationalconstraints on their relative distance, relative velocity, and masses. Allowingfor a comparable amount of diffuse mass to fill the volume of the Local Group,we find that the two galaxies are likely to collide in a few billion years -within the Sun's lifetime. During the the interaction, there is a chance thatthe Sun will be pulled away from its present orbital radius and reside in anextended tidal tail. The likelihood for this outcome increases as the mergerprogresses, and there is a remote possibility that our Sun will be more tightlybound to Andromeda than to the Milky Way before the final merger. Eventually,after the merger has completed, the Sun is most likely to be scattered to theouter halo and reside at much larger radii (>30 kpc). The density profiles ofthe stars, gas and dark matter in the merger product resemble those ofelliptical galaxies. Our Local Group model therefore provides a prototypeprogenitor of late--forming elliptical galaxies.


Instruction: what is the prompt that generates the input?

Input: Searches for the permanent electric dipole moments (EDMs) of diamagneticatoms provide powerful probes of CP-violating hadronic and semileptonicinteractions. The theoretical interpretation of such experiments, however,requires careful implementation of a well-known theorem by Schiff that impliesa vanishing net EDM for an atom built entirely from point-like, nonrelativisticconstituents that interact only electrostatically. Any experimental observationof a nonzero atomic EDM would result from corrections to the point-like,nonrelativistic, electrostatic assumption. We reformulate Schiff's theorem atthe operator level and delineate the electronic and nuclear operators whoseatomic matrix elements generate corrections to "Schiff screening". We obtain aform for the operator responsible for the leading correction associated withfinite nuclear size -- the so-called "Schiff moment" operator -- and observethat it differs from the corresponding operator used in previous Schiff momentcomputations. We show that the more general Schiff moment operator reduces tothe previously employed operator only under certain approximations that are notgenerally justified. We also identify other corrections to Schiff screeningthat may not be included properly in previous theoretical treatments. Wediscuss practical considerations for obtaining a complete computation ofcorrections to Schiff screening in atomic EDM calculations.


Instruction: what is the prompt that generates the input?

Input: As part of preparations for a southern sky search for faint Milky Way dwarfgalaxy satellites, we report the discovery of a stellar overdensity in theSloan Digital Sky Survey Data Release 5, lying at an angular distance of only1.5 degrees from the recently discovered Bo{\"o}tes dwarf. The overdensity wasdetected well above statistical noise by employing a sophisticated data miningalgorithm and does not correspond to any catalogued object. Overlaid isochronesusing stellar population synthesis models show that the color-magnitude diagramof that region has the signature of an old (12 Gyr), metal-poor (${\rmFe/H}\approx-2.0$) stellar population at a tentative distance of 60 kpc,evidently the same heliocentric distance as the Bo\"otes dwarf. We estimate thenew object to have a total magnitude of $M_{V}\sim-3.1\pm1.1$ mag and ahalf-light radius of $r_{h}=4'.1\pm1'.6$ ($72\pm28$ pc) placing it in anapparent $40<r_{h}<100$ pc void between globular clusters and dwarf galaxies,occupied only by another recently discovered Milky Way Satellite, ComaBerenices.


Instruction: what is the prompt that generates the input?

Input: We present 0.8 to 2.4 micron spectral observations of uranian satellites,obtained at IRTF/SpeX on 17 nights during 2001-2005. The spectra reveal for thefirst time the presence of CO2 ice on the surfaces of Umbriel and Titania, bymeans of 3 narrow absorption bands near 2 microns. Several additional, weakerCO2 ice absorptions have also been detected. No CO2 absorption is seen inOberon spectra, and the strengths of the CO2 ice bands decline withplanetocentric distance from Ariel through Titania. We use the CO2 absorptionsto map the longitudinal distribution of CO2 ice on Ariel, Umbriel, and Titania,showing that it is most abundant on their trailing hemispheres. We also examineH2O ice absorptions in the spectra, finding deeper H2O bands on the leadinghemispheres of Ariel, Umbriel, and Titania, but the opposite pattern on Oberon.Potential mechanisms to produce the observed longitudinal and planetocentricdistributions of the two ices are considered.


Instruction: what is the prompt that generates the input?

Input: In this paper we derive new expected scaling relations for clusters withgiant radio halos in the framework of the re-acceleration scenario in asimplified, but physically motivated, form, namely: radio power (P_R) vs sizeof the radio emitting region (R_H), and P_R vs total cluster mass (M_H)contained in the emitting region and cluster velocity dispersion (sigma_H) inthis region.  We search for these correlations by analyzing the most recent radio and X-raydata available in the literature for a well known sample of clusters with giantradio halos. In particular we find a good correlation between P_R and R_H and avery tight ``geometrical'' scaling between M_H and R_H. From these correlationsP_R is also expected to scale with M_H and sigma_H and this is confirmed by ouranalysis. We show that all the observed trends can be well reconciled withexpectations in the case of a slight variation of the mean magnetic fieldstrength in the radio halo volume with M_H. A byproduct correlation between R_Hand sigma_H is also found, and can be further tested by optical studies. Inaddition, we find that observationally R_H scales non-linearly with the virialradius of the host cluster, and this immediately means that the fraction of thecluster volume which is radio emitting increases with cluster mass and thusthat the non-thermal component in clusters is not self-similar.


Instruction: what is the prompt that generates the input?

Input: Aims and Methods: We present the results of VLBI observations of nineteenGHz-Peaked-Spectrum (GPS) radio sources at 1.6 GHz. Of them, 15 sources areselected from the Parkes Half Jansky (PHJ) sample (Snellen 2002), 4 others arefrom our previous observation list. We aimed at imaging the structure of GPSsources, searching for Compact Symmetric Objects (CSOs) and studying theabsorption for the convex radio spectra of GPS sources.  Results: We obtained total intensity 1.6 GHz VLBI images of 17 sources forthe first time. Of them, 80% show mini-double-lobe radio structure, indicatingthat they are CSOs or candidates, and their host AGNs could be edge-on to us.This result suggests that there is a high incidence of mini double-lobe sources(or CSOs) in the PHJ sample. The sources J0323+0534, J1135-0021, J1352+0232,J2058+0540, J2123-0112 and J2325-0344 with measured redshift, showingdouble-lobe structure with sizes of <1 kpc, are classified as CSOs. Threesources J1057+0012, J1600-0037 and J1753+2750 are considered as core-jetsources according to their morphologies and flux variability.


Instruction: what is the prompt that generates the input?

Input: We detect a dip of 20-45% in the surface brightness and number counts of NVSSsources smoothed to a few degrees at the location of the WMAP cold spot. Thedip has structure on scales of approximately 1-10 degrees. Together withindependent all-sky wavelet analyses, our results suggest that the dip inextragalactic brightness and number counts and the WMAP cold spot arephysically related, i.e., that the coincidence is neither a statistical anomalynor a WMAP foreground correction problem. If the cold spot does originate fromstructures at modest redshifts, as we suggest, then there is no remaining needfor non-Gaussian processes at the last scattering surface of the CMB to explainthe cold spot. The late integrated Sachs-Wolfe effect, already seenstatistically for NVSS source counts, can now be seen to operate on a singleregion. To create the magnitude and angular size of the WMAP cold spot requiresa ~140 Mpc radius completely empty void at z<=1 along this line of sight. Thisis far outside the current expectations of the concordance cosmology, and addsto the anomalies seen in the CMB.


Instruction: what is the prompt that generates the input?

Input: The Stark shift of the hyperfine coupling constant is investigated for a Pdonor in Si far below the ionization regime in the presence of interfaces usingTight-binding and Band Minima Basis approaches and compared to the recentprecision measurements. The TB electronic structure calculations included over3 million atoms. In contrast to previous effective mass based results, thequadratic Stark coefficient obtained from both theories agrees closely with theexperiments. This work represents the most sensitive and precise comparisonbetween theory and experiment for single donor spin control. It is also shownthat there is a significant linear Stark effect for an impurity near theinterface, whereas, far from the interface, the quadratic Stark effectdominates. Such precise control of single donor spin states is requiredparticularly in quantum computing applications of single donor electronics,which forms the driving motivation of this work.


Instruction: what is the prompt that generates the input?

Input: We analyse star formation in the nuclei of 9 Seyfert galaxies at spatialresolutions down to 0.085arcsec, corresponding to length scales of less than10pc in some objects. Our data were taken mostly with the near infraredadaptive optics integral field spectrograph SINFONI. The stellar light profilestypically have size scales of a few tens of parsecs. In two cases there isunambiguous kinematic evidence for stellar disks on these scales. In thenuclear regions there appear to have been recent - but no longer active -starbursts in the last 10-300Myr. The stellar luminosity is less than a fewpercent of the AGN in the central 10pc, whereas on kiloparsec scales theluminosities are comparable. The surface stellar luminosity density follows asimilar trend in all the objects, increasing steadily at smaller radii up to10^{13}L_sun/kpc^2 in the central few parsecs, where the mass surface densityexceeds 10^4M_sun/pc^2. The intense starbursts were probably Eddington limitedand hence inevitably short-lived, implying that the starbursts occur inmultiple short bursts. The data hint at a delay of 50--100Myr between the onsetof star formation and subsequent fuelling of the black hole. We discuss whetherthis may be a consequence of the role that stellar ejecta could play infuelling the black hole. While a significant mass is ejected by OB winds andsupernovae, their high velocity means that very little of it can be accreted.On the other hand winds from AGB stars ultimately dominate the total mass loss,and they can also be accreted very efficiently because of their slow speeds.


Instruction: what is the prompt that generates the input?

Input: In a 2002 paper, the authors and Bruner used the new spectrum tmf to obtainsome new nonimmersions of real projective spaces. In this note, wecomplete/correct two oversights in that paper.  The first is to note that in that paper a general nonimmersion result wasstated which yielded new nonimmersions for RP^n with n as small as 48, and yetit was stated there that the first new result occurred when n=1536. Here wegive a simple proof of those overlooked results.  Secondly, we fill in a gap in the proof of the 2002 paper. There it wasclaimed that an axial map f must satisfy f^*(X)=X_1+X_2. We realized recentlythat this is not clear. However, here we show that it is true up multiplicationby a unit in the appropriate ring, and so we retrieve all the nonimmersionresults claimed in the original paper.  Finally, we present a complete determination of tmf^{8*}(RP^\infty\timesRP^\infty) and tmf^*(CP^\infty\times CP^\infty) in positive dimensions.


Instruction: what is the prompt that generates the input?

Input: We present a search for the decay B+ -> tau+ nu using 383x10^6 BBbar pairscollected at the Y(4S) resonance with the BABAR detector at the SLAC PEP-IIB-Factory. A sample of events with one reconstructed semileptonic B decay (B--> D0 l nu X)) is selected, and in the recoil a search for B+ -> tau+ nu isperformed. The tau is identified in the following channels: tau+ -> e nu nubar,tau+ -> mu nu nubar, tau+ -> pi+ nu, and tau+ -> pi+ pi0 nu. We measure abranching fraction of B(B+ -> tau+ nu)=(0.9 +- 0.6(stat.) +- 0.1(syst.)) x10^-4. In the absence of a significant signal, we calculate an upper limit atthe 90% confidence level of B(B+ -> tau+ nu) < 1.7 x 10^-4. We calculate theproduct of the B meson decay constant f_B and |V_ub| to be f_B x |V_ub| =(7.2^{+2.0}_{-2.8}(stat.) +- 0.2 (syst.)) x 10^-4 GeV.


Instruction: what is the prompt that generates the input?

Input: This paper presents a hybrid approach to spatial indexing of two dimensionaldata. It sheds new light on the age old problem by thinking of the traditionalalgorithms as working with images. Inspiration is drawn from an analogoussituation that is found in machine and human vision. Image processingtechniques are used to assist in the spatial indexing of the data. A fixed gridapproach is used and bins with too many records are sub-divided hierarchically.Search queries are pre-computed for bins that do not contain any data records.This has the effect of dividing the search space up into non rectangularregions which are based on the spatial properties of the data. The bucketingquad tree can be considered as an image with a resolution of two by two foreach layer. The results show that this method performs better than the quadtree if there are more divisions per layer. This confirms our suspicions thatthe algorithm works better if it gets to look at the data with higherresolution images. An elegant class structure is developed where theimplementation of concrete spatial indexes for a particular data type merelyrelies on rendering the data onto an image.


Instruction: what is the prompt that generates the input?

Input: We present the first strong lensing study of the mass distribution in thecluster MS 2053-04 based on HST archive data. This massive, X-ray luminouscluster has a redshift z=0.583, and it is composed of two structures that aregravitationally bound to each other. The cluster has one multiply imaged systemconstituted by a double gravitational arc.  We have performed a parametric strong lensing mass reconstruction using NFWdensity profiles to model the cluster potential. We also included perturbationsfrom 23 galaxies, modeled like elliptical singular isothermal sphere, that areapproximately within 1'x1' around the cluster center. These galaxies wereconstrained in both the geometric and dynamical parameters with observationaldata. Our analysis predicts a third image which is slightly demagnified. Wefound a candidate for this counter-image near the expected position and withthe same F702W-F814W colors as the gravitational arcs in the cluster. Theresults from the strong lensing model shows the complex structure in thiscluster, the asymmetry and the elongation in the mass distribution, and areconsistent with previous spectrophotometric results that indicate that thecluster has a bimodal mass distribution. Finally, the derived mass profile wasused to estimate the mass within the arcs and for comparison with X-rayestimates.


Instruction: what is the prompt that generates the input?

Input: In the last decade evidence has accumulated that small domains of 50-700 nmin diameter are located in the exoplasmic leaflet of the plasma membrane. Mostof these domains supposedly consist of specific sets of lipids and proteins,and are believed to coordinate signal transduction cascades. Whether similardomains are also present in the cytoplasmic leaflet of the plasma membrane isunclear so far. To investigate the presence of cytoplasmic leaflet domains, theH-Ras membrane-targeting sequence was fused to the C-terminus of the enhancedyellow fluorescent protein. Using single-molecule fluorescence microscopy,trajectories of individual molecules diffusing in the cytoplasmic leaflet ofthe plasma membrane were recorded. From these trajectories, the diffusion ofindividual membrane-anchored enhanced yellow fluorescent protein molecules wasstudied in live cells on timescales from 5 to 200 ms. The results show that thediffusion of 30-40% of the molecules is constrained in domains with a typicalsize of 200 nm. Neither breakdown of actin nor cholesterol extraction changedthe domain characteristics significantly, indicating that the observed domainsmay not be related to the membrane domains identified so far.


Instruction: what is the prompt that generates the input?

Input: We investigate dynamical properties of bright solitons with a finitebackground in the F=1 spinor Bose-Einstein condensate (BEC), based on anintegrable spinor model which is equivalent to the matrix nonlinearSchr\"{o}dinger equation with a self-focusing nonlineality. We apply theinverse scattering method formulated for nonvanishing boundary conditions. Theresulting soliton solutions can be regarded as a generalization of those undervanishing boundary conditions. One-soliton solutions are derived in an explicitmanner. According to the behaviors at the infinity, they are classified intotwo kinds, domain-wall (DW) type and phase-shift (PS) type. The DW-type impliesthe ferromagnetic state with nonzero total spin and the PS-type implies thepolar state, where the total spin amounts to zero. We also discuss two-solitoncollisions. In particular, the spin-mixing phenomenon is confirmed in acollision involving the DW-type. The results are consistent with those of theprevious studies for bright solitons under vanishing boundary conditions anddark solitons. As a result, we establish the robustness and the usefulness ofthe multiple matter-wave solitons in the spinor BECs.


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Input: We present the results of realistic N-body modelling of massive star clustersin the Magellanic Clouds, aimed at investigating a dynamical origin for theradius-age trend observed in these systems. We find that stellar-mass blackholes, formed in the supernova explosions of the most massive cluster stars,can constitute a dynamically important population. If a significant number ofblack holes are retained (here we assume complete retention), these objectsrapidly form a dense core where interactions are common, resulting in thescattering of black holes into the cluster halo, and the ejection of blackholes from the cluster. These two processes heat the stellar component,resulting in prolonged core expansion of a magnitude matching the observations.Significant core evolution is also observed in Magellanic Cloud clusters atearly times. We find that this does not result from the action of black holes,but can be reproduced by the effects of mass-loss due to rapid stellarevolution in a primordially mass segregated cluster.


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Input: Heteroepitaxial self-assembled quantum dots (SAQDs) will allow breakthroughsin electronics and optoelectronics. SAQDs are a result of Stranski-Krastanowgrowth whereby a growing planar film becomes unstable after an initial wettinglayer is formed. Common systems are Ge$_{x}$Si$_{1-x}$/Si andIn$_{x}$Ga$_{1-x}$As/GaAs. For applications, SAQD arrays need to be ordered.The role of crystal anisotropy, random initial conditions and thermalfluctuations in influencing SAQD order during early stages of SAQD formation isstudied through a simple stochastic model of surface diffusion. Surfacediffusion is analyzed through a linear and perturbatively nonlinear analysis.The role of crystal anisotropy in enhancing SAQD order is elucidated. It isalso found that SAQD order is enhanced when the deposited film is allowed toevolve at heights near the critical wetting surface height that marks the onsetof non-planar film growth.


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Input: The Cosmic Far-Infrared Background (CFIRB) contains information about thenumber and distribution of contributing sources and thus gives us an importantkey to understand the evolution of galaxies. Using a confusion study to set afundamental limit to the observations, we investigate the potential to explorethe CFIRB with AKARI/FIS deep observations. The Far-Infrared Surveyor (FIS) isone of the focal-plane instruments on the AKARI (formerly known as ASTRO-F)satellite, which was launched in early 2006. Based upon source distributionmodels assuming three different cosmological evolutionary scenarios (noevolution, weak evolution, and strong evolution), an extensive model fordiffuse emission from infrared cirrus, and instrumental noise estimates, wepresent a comprehensive analysis for the determination of the confusion levelsfor deep far-infrared observations. We use our derived sensitivities to suggestthe best observational strategy for the AKARI/FIS mission to detect the CFIRBfluctuations. If the source distribution follows the evolutionary models,observations will be mostly limited by source confusion. We find that we willbe able to detect the CFIRB fluctuations and that these will in turn provideinformation to discriminate between the evolutionary scenarios of galaxies inmost low-to-medium cirrus regions.


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Input: Prominent ethical and policy issues such as affirmative action and femaleenrollment in science and engineering revolve around the idea that diversity isgood. However, even though diversity is an ambiguous concept, a precisedefinition is seldom provided. We show that diversity may be construed as afactual description, a craving for symmetry, an intrinsic good, an instrumentalgood, a symptom, or a side effect. These acceptions differ vastly in theirnature and properties. The first one cannot lead to any action and the secondone is mistaken. Diversity as intrinsic good is a mere opinion, which cannot beconcretely applied; moreover, the most commonly invoked forms of diversity(sexual and racial) are not intrinsically good. On the other hand, diversity asinstrumental good can be evaluated empirically and can give rise to policies,but these may be very weak. Finally, symptoms and side effects are not actuallyabout diversity. We consider the example of female enrollment in science andengineering, interpreting the various arguments found in the literature inlight of this polysemy.  Keywords: ethics, policy, higher education, female students, minoritystudents, affirmative action


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Input: Electromechanical coupling is ubiquitous in biological systems with examplesranging from simple piezoelectricity in calcified and connective tissues tovoltage-gated ion channels, energy storage in mitochondria, andelectromechanical activity in cardiac myocytes and outer hair cell stereocilia.Piezoresponse force microscopy (PFM) has originally emerged as a technique tostudy electromechanical phenomena in ferroelectric materials, and in recentyears, has been employed to study a broad range of non-ferroelectric polarmaterials, including piezoelectric biomaterials. At the same time, thetechnique has been extended from ambient to liquid imaging on modelferroelectric systems. Here, we present results on local electromechanicalprobing of several model cellular and biomolecular systems, including insulinand lysozyme amyloid fibrils, breast adenocarcinoma cells, andbacteriorhodopsin in a liquid environment. The specific features of SPMoperation in liquid are delineated and bottlenecks on the route towardsnanometer-resolution electromechanical imaging of biological systems areidentified.


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Input: Recently, much research has been carried out on Hamiltonians that are notHermitian but are symmetric under space-time reflection, that is, Hamiltoniansthat exhibit PT symmetry. Investigations of the Sturm-Liouville eigenvalueproblem associated with such Hamiltonians have shown that in many cases theentire energy spectrum is real and positive and that the eigenfunctions form anorthogonal and complete basis. Furthermore, the quantum theories determined bysuch Hamiltonians have been shown to be consistent in the sense that theprobabilities are positive and the dynamical trajectories are unitary. However,the geometrical structures that underlie quantum theories formulated in termsof such Hamiltonians have hitherto not been fully understood. This paperstudies in detail the geometric properties of a Hilbert space endowed with aparity structure and analyses the characteristics of a PT-symmetric Hamiltonianand its eigenstates. A canonical relationship between a PT-symmetric operatorand a Hermitian operator is established. It is shown that the quadratic formcorresponding to the parity operator, in particular, gives rise to a naturalpartition of the Hilbert space into two halves corresponding to states havingpositive and negative PT norm. The indefiniteness of the norm can becircumvented by introducing a symmetry operator C that defines a positivedefinite inner product by means of a CPT conjugation operation.


Instruction: what is the prompt that generates the input?

Input: Observations of stellar activity cycles provide an opportunity to studymagnetic dynamos under many different physical conditions. Space-basedasteroseismology missions will soon yield useful constraints on the interiorconditions that nurture such magnetic cycles, and will be sensitive enough todetect shifts in the oscillation frequencies due to the magnetic variations. Wederive a method for predicting these shifts from changes in the Mg II activityindex by scaling from solar data. We demonstrate this technique on thesolar-type subgiant beta Hyi, using archival International Ultraviolet Explorerspectra and two epochs of ground-based asteroseismic observations. We findqualitative evidence of the expected frequency shifts and predict the optimaltiming for future asteroseismic observations of this star.


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Input: We report on the measurement of element-specific magnetic resonance spectraat gigahertz frequencies using x-ray magnetic circular dichroism (XMCD). Weinvestigate the ferrimagnetic precession of Gd and Fe ions in Gd-substitutedYttrium Iron Garnet, showing that the resonant field and linewidth of Gdprecisely coincide with Fe up to the nonlinear regime of parametricexcitations. The opposite sign of the Gd x-ray magnetic resonance signal withrespect to Fe is consistent with dynamic antiferromagnetic alignment of the twoionic species. Further, we investigate a bilayer metal film,Ni$_{80}$Fe$_{20}$(5 nm)/Ni(50 nm), where the coupled resonance modes of Ni andNi$_{80}$Fe$_{20}$ are separately resolved, revealing shifts in the resonancefields of individual layers but no mutual driving effects. Energy-dependentdynamic XMCD measurements are introduced, combining x-ray absorption andmagnetic resonance spectroscopies.


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Input: We use the Barnard 68 dark globule as a test case for a spherically symmetricPDR model exposed to low-UV radiation fields. With a roughly sphericalmorphology and an accurately determined density profile, Barnard 68 is idealfor this purpose. The processes governing the energy balance in the cloudsurface are studied in detail. We compare the spherically symmetric PDR modelby Stoerzer, Stutzki & Sternberg (1996) to observations of the three lowestrotational transitions of 12CO, 13CO J = 2-1 and J = 3-2 as well as the [CI]3P_1-3P_0 fine structure transition. We study the role of Polycyclic AromaticHydrocarbons (PAHs) in the chemical network of the PDR model and consider theimpact of depletion as well as of a variation of the external FUV field. Wefind it difficult to simultaneously model the observed 12CO and 13CO emission.The 12CO and [CI] emission can be explained by a PDR model with a external FUVfield of 1-0.75 chi_0, but this model fails to reproduce the observed 13CO by afactor of ~2. Adding PAHs to the chemical network increases the [CI] emissionby 50% in our model but makes [CII] very faint. CO depletion only slightlyreduces the 12CO and 13CO line intensity (by <10% and <20%, respectively).Predictions for the [CII] 2P_3/2-2P_1/2, [CI] 3P_2-3P_1 and 12CO J= 5-4 and 4-3transitions are presented. This allows a test of our model with futureobservations (APEX, NANTEN2, HERSCHEL, SOFIA).


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Input: We have investigated the influence of nuclear parameters such as black hole(BH) mass and photoionizing luminosity on the FRI/FRII transition in a sampleof nearby (z<0.2) 3CR radio galaxies. The sample was observed withmedium-resolution, optical spectroscopy and contains some galaxies withunpublished velocity dispersion measurements and emission-line fluxes. Measuredvelocity dispersions are 130-340 km/s with a mean of 216 km/s. Converting to BHmass, we find that the BH mass distribution is identical for FRIs and FRIIs,with a mean of approximately 2.5x10^8 Msun. We convert [OII] and [OIII]emission-line luminosities to photoionizing luminosity under the assumptionthat the gas is ionized by the nuclear UV continuum. Most of the galaxies withFRI morphology and/or low-excitation emission-line spectra have progressivelylower BH masses at lower photoionizing (and jet) luminosities. This agrees withthe Ledlow-Owen relation which states that the radio luminosity at the FRI/FRIItransition depends on the optical luminosity of the host, L_radio ~L_optical^1.8, because both L_radio and L_optical relate to AGN nuclearparameters. When recasting the Ledlow-Owen relation into BH mass versusphotoionizing and jet luminosity, we find that the recasted relation describesthe sample quite well. The FRI/FRII transition occurs at approximately an orderof magnitude lower luminosity relative to the Eddington luminosity than thesoft-to-hard transition in X-ray binaries. This difference is consistent withthe Ledlow-Owen relation, which predicts a weak BH mass dependence in thetransition luminosity. We conclude that the FRI/FRII dichotomy is caused by acombination of external and nuclear factors, with the latter dominating.


Instruction: what is the prompt that generates the input?

Input: Quantum computers have the capability of out-performing their classicalcounterparts for certain computational problems. Several scalable quantumcomputing architectures have been proposed. An attractive architecture is alarge set of physically independant qubits, arranged in three spatial regionswhere (i) the initialized qubits are stored in a register, (ii) two qubits arebrought together to realize a gate, and (iii) the readout of the qubits isperformed. For a neutral atom-based architecture, a natural way to connectthese regions is to use optical tweezers to move qubits within the system. Inthis letter we demonstrate the coherent transport of a qubit, encoded on anatom trapped in a sub-micron tweezer, over a distance typical of the separationbetween atoms in an array of optical traps. Furthermore, we transfer a qubitbetween two tweezers, and show that this manipulation also preserves thecoherence of the qubit.


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Input: We characterize the molecular environment of candidate massive young stellarobjects (MYSOs) signposted by methanol masers. Single pixel observations of 10transitions of HCO^+, CO and CS isotopomers were carried out, using the IRAM30m telescope. We studied a sample of 28 targets for which the 6.7GHz maseremission positions are known with a sub-arcsecond accuracy. The systemicvelocity inferred from the optically thin lines agrees within 3km/s with thecentral velocity of the maser emission for most of the sources. About 64% ofthe sources show line wings in one or more transitions of CO, HCO^+ and CSspecies, indicating the presence of molecular outflows. Comparison of thewidths of line wings and methanol maser emission suggests that the 6.7GHz maserline traces the environment of MYSO of various kinematic regimes. Thereforeconditions conducive for the methanol maser can exist in the inner parts ofmolecular clouds or circumstellar discs as well as in the outer partsassociated with molecular outflows. Calculations of the physical conditionsbased on the CO and HCO^+ lines and the CS line intensity ratios refine theinput parameters for maser models.


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Input: We present SEST observations of the molecular environment ahead of thesouthern Herbig-Haro object 188 (HH188), associated with the low-mass protostarRe4 IRS. We have also used the SuperCosmos Halpha survey to search for Halphaemission associated with the Re4 IRS - HH188 region. The aim of the presentwork is to study the properties of the molecular gas and to better characterizethis southern star forming region. We mapped the HCO+ 3-2 and H13CO+ 1-0emission around the YSO and took spectra of the CH3OH 2(0)-1(0)A+ and2(-1)-1(-1)E and SO 6(5)-5(4) towards the central source. Column densities arederived and different scenarios are considered to explain the origin of themolecular emission. HCO+ arises from a relatively compact region around theYSO; however, its peak emission is displaced to the south following the outflowdirection. Our chemical analysis indicates that a plausible scenario is thatmost of the emission arises from the cold, illuminated dense gas ahead of theHH188 object. We have also found that HH188, a high excitation object, seems tobe part of a parsec scale and highly collimated HH system. Re4 IRS is probablya binary protostellar system, in the late Class 0 or Class I phase. One of theprotostars, invisible in the near-IR, seems to power the HH188 system.


Instruction: what is the prompt that generates the input?

Input: The effect of Ge substitution for Si in SmMMn2Si2-xGex compounds has beenstudied. The Sm ordering temperature is found to be much larger in the compoundwith x=2, as compared to the compounds with x=0 and 1. The increase in theintra layer Mn-Mn distance is found to be responsible for this increase. Amongthese three compounds, SmMn2Ge2 is found to show re-entrant ferromagnetism atlow temperatures. The magnetic contribution to the heat capacity has been foundin all the three compounds. The splitting of the ground state multiplet hasbeen estimated by fitting the magnetic part of the heat capacity data using theSchottky formula. The isothermal magnetic entropy change is found to remain thesame for x=0 and 1, but decrease in the compound with x=2, though the nature ofmagnetic transition changes from second order to first order, as x is increasedfrom 0 to 2. The electrical resistivity increases with Ge concentration. Theexcess resistivity in the antiferromagnetic region has been calculated.


Instruction: what is the prompt that generates the input?

Input: Bigravity is a natural arena where a non-linear theory of massive gravity canbe formulated. If the interaction between the metrics $f$ and $g$ isnon-derivative, spherically symmetric exact solutions can be found. At largedistances from the origin, these are generically Lorentz-breaking bi-flatsolutions (provided that the corresponding vacuum energies are adjustedappropriately). The spectrum of linearized perturbations around suchbackgrounds contains a massless as well as a massive graviton, with {\em two}physical polarizations each. There are no propagating vectors or scalars, andthe theory is ghost free (as happens with certain massive gravities withexplicit breaking of Lorentz invariance). At the linearized level, correctionsto GR are proportional to the square of the graviton mass, and so there is novDVZ discontinuity. Surprisingly, the solution of linear theory for a staticspherically symmetric source does {\em not} agree with the linearization of anyof the known exact solutions. The latter coincide with the standardSchwarzschild-(A)dS solutions of General Relativity, with no corrections atall. Another interesting class of solutions is obtained where $f$ and $g$ areproportional to each other. The case of bi-de Sitter solutions is analyzed insome detail.


Instruction: what is the prompt that generates the input?

Input: We investigate the generation of quantum operations for one-qubit systemsunder classical noise with 1/f^\alpha power spectrum, where 2>\alpha > 0. Wepresent an efficient way to approximate the noise with a discrete multi-stateMarkovian fluctuator. With this method, the average temporal evolution of thequbit density matrix under 1/f^\alpha noise can be feasibly determined fromrecently derived deterministic master equations. We obtain qubit operationssuch as quantum memory and the NOT}gate to high fidelity by a gradient basedoptimization algorithm. For the NOT gate, the computed fidelities arequalitatively similar to those obtained earlier for random telegraph noise. Inthe case of quantum memory however, we observe a nonmonotonic dependency of thefidelity on the operation time, yielding a natural access rate of the memory.


Instruction: what is the prompt that generates the input?

Input: The structure of three laminar premixed rich flames has been investigated: apure methane flame and two methane flames doped by allene and propyne,respectively. The gases of the three flames contain 20.9% (molar) of methaneand 33.4% of oxygen, corresponding to an equivalence ratio of 1.25 for the puremethane flame. In both doped flames, 2.49% of C3H4 was added, corresponding toa ratio C3H4/CH4 of 12% and an equivalence ratio of 1.55. The three flames havebeen stabilized on a burner at a pressure of 6.7 kPa using argon as dilutant,with a gas velocity at the burner of 36 cm/s at 333 K. The concentrationprofiles of stable species were measured by gas chromatography after samplingwith a quartz microprobe. Quantified species included carbon monoxide anddioxide, methane, oxygen, hydrogen, ethane, ethylene, acetylene, propyne,allene, propene, propane, 1,2-butadiene, 1,3-butadiene, 1-butene, isobutene,1-butyne, vinylacetylene, and benzene. The temperature was measured using aPtRh (6%)-PtRh (30%) thermocouple settled inside the enclosure and ranged from700 K close to the burner up to 1850 K. In order to model these new results,some improvements have been made to a mechanism previously developed in ourlaboratory for the reactions of C3-C4 unsaturated hydrocarbons. The mainreaction pathways of consumption of allene and propyne and of formation of C6aromatic species have been derived from flow rate analyses.


Instruction: what is the prompt that generates the input?

Input: According to extensive experimental findings, the Ginzburg temperature$t_{G}$ for ionic fluids differs substantially from that of nonionic fluids[Schr\"oer W., Weig\"{a}rtner H. 2004 {\it Pure Appl. Chem.} {\bf 76} 19]. Atheoretical investigation of this outcome is proposed here by a mean fieldanalysis of the interplay of short and long range interactions on the value of$t_{G}$. We consider a quite general continuous charge-asymmetric model made ofcharged hard spheres with additional short-range interactions (withoutelectrostatic interactions the model belongs to the same universality class asthe 3D Ising model). The effective Landau-Ginzburg Hamiltonian of the fullsystem near its gas-liquid critical point is derived from which the Ginzburgtemperature is calculated as a function of the ionicity. The results obtainedin this way for $t_{G}$ are in good qualitative and sufficient quantitativeagreement with available experimental data.


Instruction: what is the prompt that generates the input?

Input: We investigate the optical properties of one-dimensional (1D) dimerized Mottinsulators using the 1D dimerized extended Hubbard model. Numericalcalculations and a perturbative analysis from the decoupled-dimer limit clarifythat there are three relevant classes of charge-transfer (CT) states generatedby photoexcitation: interdimer CT unbound states, interdimer CT exciton states,and intradimer CT exciton states. This classification is applied tounderstanding the optical properties of an organic molecular material,1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), which is known for itsphotoinduced transition from the dimerized spin-singlet phase to the regularparamagnetic phase. We conclude that the lowest photoexcited state of TTTA isthe interdimer CT exciton state and the second lowest state is the intradimerCT exciton state.


Instruction: what is the prompt that generates the input?

Input: Mn3V2O8 is a magnetic system in which S = 5/2 Mn2+ is found in the kagomestaircase lattice. Here we report the magnetic phase diagram for temperaturesabove 2 K and applied magnetic fields below 9 T, characterized by measurementsof the magnetization and specific heat with field along the three uniquelattice directions. At low applied magnetic fields, the system first ordersmagnetically below Tm1 ~ 21 K, and then shows a second magnetic phasetransition at Tm2 ~ 15 K. In addition, a phase transition that is apparent inspecific heat but not seen in magnetization is found for all three appliedfield orientations, converging towards Tm2 as H -> 0. The magnetic behavior ishighly anisotropic, with critical fields for magnetic phase boundaries muchhigher when the field is applied perpendicular to the Kagome staircase planethan when applied in-plane. The field-temperature (H - T) phase diagrams arequite rich, with 7 distinct phases observed.


Instruction: what is the prompt that generates the input?

Input: A k-query Locally Decodable Code (LDC) encodes an n-bit message x as an N-bitcodeword C(x), such that one can probabilistically recover any bit x_i of themessage by querying only k bits of the codeword C(x), even after some constantfraction of codeword bits has been corrupted. The major goal of LDC relatedresearch is to establish the optimal trade-off between length and querycomplexity of such codes.  Recently [Y] introduced a novel technique for constructing locally decodablecodes and vastly improved the upper bounds for code length. The technique isbased on Mersenne primes. In this paper we extend the work of [Y] and arguethat further progress via these methods is tied to progress on an old numbertheory question regarding the size of the largest prime factors of Mersennenumbers.  Specifically, we show that every Mersenne number m=2^t-1 that has a primefactor p>m^\gamma yields a family of k(\gamma)-query locally decodable codes oflength Exp(n^{1/t}). Conversely, if for some fixed k and all \epsilon > 0 onecan use the technique of [Y] to obtain a family of k-query LDCs of lengthExp(n^\epsilon); then infinitely many Mersenne numbers have prime factors argerthan known currently.


Instruction: what is the prompt that generates the input?

Input: Density-functional theory has been applied to investigate systematics ofsodium clusters Na_n in the size range of n= 39-55. A clear evolutionary trendin the growth of their ground-state geometries emerges. The clusters at thebeginning of the series (n=39-43) are symmetric and have partial icosahedral(two-shell) structure. The growth then goes through a series of disorderedclusters (n=44-52) where the icosahedral core is lost. However, for n>52 athree shell icosahedral structure emerges. This change in the nature of thegeometry is abrupt. In addition, density-functional molecular dynamics has beenused to calculate the specific heat curves for the representative sizes n= 43,45, 48 and 52. These results along with already available thermodynamiccalculations for n= 40, 50, and 55 enable us to carry out a detailed comparisonof the heat capacity curves with their respective geometries for the entireseries. Our results clearly bring out strong correlation between the evolutionof the geometries and the nature of the shape of the heat capacities. Theresults also firmly establish the size-sensitive nature of the heat capacitiesin sodium clusters.


Instruction: what is the prompt that generates the input?

Input: The stationary hydrodynamic equations for the transonic accretion disks andflows around rotating black holes are presented by using the Kerr-Schildcoordinate where there is no coordinate singularity at the event horizon. Weuse two types of the causal viscosity prescription, and the boundary conditionsfor the transonic accretion flows are given at the sonic point. For one type ofthe causal viscosity prescription we also add the boundary conditions at theviscous point where the accreting radial velocity is nearly equal to theviscous diffusion velocity. Based on the formalism for the transonic accretiondisks, after we present the calculation method of the transonic solutions, thehorizon-penetrating transonic solutions which smoothly pass the event horizonare calculated for several types of the accretion flow models: the idealisothermal flows, the ideal and the viscous polytropic flows, the advectiondominated accretion flows (ADAFs) with the relativistic equation of state, theadiabatic accretion disks, the standard accretion disks, the supercriticalaccretion disks. These solutions are obtained for both non-rotating androtating black holes. The calculated accretion flows plunge into black holewith finite three velocity smaller than the speed of light even at the eventhorizon or inside the horizon, and the angular velocities of the accretion flowat the horizon are generally different from the angular velocity of theframe-dragging due to the black hole's rotation. These features contrast to theresults obtained by using the Boyer-Lindquist coordinate with the coordinatesingularity at the horizon.


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Input: Phenomenologically viable and interesting regions of parameter space in theminimal super-gravity (mSUGRA) model with small $m_0$ and small $m_{1/2}$consistent with the WMAP data on dark matter relic density and the bound on themass of the lightest Higgs scalar $ m_h>$ 114 GeV from LEP2 open up if therather adhoc assumption $A_0$=0, where $A_0$ is the common trilinear softbreaking parameter, employed in most of the existing analyses is relaxed. Sincethis region corresponds to relatively light squarks and gluinos which arelikely to be probed extensively in the very early stages of the LHCexperiments, the consequences of moderate or large negative values of $A_0$ areexamined in detail. We find that in this region several processes includinglightest supersymmetric particle (LSP) pair annihilation, LSP - lighter tauslepton (${\tilde \tau}_1$) coannihilation and LSP - lighter top squark(${\tilde t}_1$) coannihilation contribute to the observed dark matter relicdensity. %\sout{The possibility that a relic density producing ${\tilde t}_1$can be %observed at the current experiments at the Tevatron is wide open.} Thepossibility that a ${\tilde t}_1$ that can participate in coannihilation withthe lightest neutralino to satisfy the WMAP bound on relic density and at thesame time be observed at the current experiments at the Tevatron is wide open.At the LHC a large number of squark - gluino events lead to a very distinctivesemi-inclusive signature $\tau^\pm$+X$_\tau$ (anything without a tau lepton)with a characteristic size much larger than $e^\pm$+X$_e$ or $\mu^\pm$+X$_\mu$events.


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Input: It has been shown recently by Kapustin and Tomasiello that the mathematicalnotion of Hamiltonian actions on twisted generalized K\"ahler manifolds is inperfect agreement with the physical notion of general $(2,2)$ gauged sigmamodels with three-form fluxes. In this article, we study the twistedequivariant cohomology theory of Hamiltonian actions on $H$-twisted generalizedcomplex manifolds. If the manifold satisfies the$\bar{\partial}\partial$-lemma, we establish the equivariant formality theorem.If in addition, the manifold satisfies the generalized K\"ahler condition, weprove the Kirwan injectivity in this setting. We then consider the Hamiltonianaction of a torus on an $H$-twisted generalized Calabi-Yau manifold and extendto this case the Duistermaat-Heckman theorem for the push-forward measure.  As a side result, we show in this paper that the generalized K\"ahlerquotient of a generalized K\"ahler vector space can never have a(cohomologically) non-trivial twisting. This gives a negative answer to aquestion asked by physicists whether one can construct $(2,2)$ gauged linearsigma models with non-trivial fluxes.


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Input: We show numerically that in a binary system of Yukawa particles, a dispersitydriven disordering transition occurs. In the presence of quenched disorder thisdisordering transition coincides with a marked increase in the depinningthreshold, known as a peak effect. We find that the addition of poorly pinnedparticles can increase the overall pinning in the sample by increasing theamount of topological disorder present. If the quenched disorder is strongenough to create a significant amount of topological disorder in themonodisperse system, addition of a poorly pinned species generates furtherdisorder but does not produce a peak in the depinning force. Our resultsindicate that for binary mixtures, optimal pinning occurs for topologicaldefect fraction densities of 0.2 to 0.25. For defect densities below thisrange, the system retains orientational order. We determine the effect of thepinning density, strength, and radius on the depinning peak and find that thepeak effect is more pronounced in weakly pinning systems.


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Input: We present photometric detections of dust emission at 850 and 450 micronaround the pre-main sequence M1 dwarf TWA 7 using the SCUBA camera on the JamesClerk Maxwell Telescope. These data confirm the presence of a cold dust diskaround TWA 7, a member of the TW Hydrae Association. Based on the 850 micronflux, we estimate the mass of the disk to be 18 lunar masses (0.2 Earth masses)assuming a mass opacity of 1.7 cm^2/g with a temperature of 45 K. This makesthe TWA 7 disk (d=55 pc) an order of magnitude more massive than the diskreported around AU Microscopii (GL 803), the closest (9.9 pc) debris diskdetected around an M dwarf. This is consistent with TWA 7 being slightlyyounger than AU Mic. We find that the mid-IR and submillimeter data require thedisk to be comprised of dust at a range of temperatures. A model in which thedust is at a single radius from the star, with a range of temperaturesaccording to grain size, is as effective at fitting the emission spectrum as amodel in which the dust is of uniform size, but has a range of temperaturesaccording to distance. We discuss this disk in the context of known disks inthe TW Hydrae Association and around low-mass stars; a comparison of masses ofdisks in the TWA reveals no trend in mass or evolutionary state (gas-rich vs.debris) as a function of spectral type.


Instruction: what is the prompt that generates the input?

Input: Integral formulae for polynomial solutions of the quantumKnizhnik-Zamolodchikov equations associated with the R-matrix of the six-vertexmodel are considered. It is proved that when the deformation parameter q isequal to e^{+- 2 pi i/3} and the number of vertical lines of the lattice isodd, the solution under consideration is an eigenvector of the inhomogeneoustransfer matrix of the six-vertex model. In the homogeneous limit it is aground state eigenvector of the antiferromagnetic XXZ spin chain with theanisotropy parameter Delta equal to -1/2 and odd number of sites. The obtainedintegral representations for the components of this eigenvector allow to provesome conjectures on its properties formulated earlier. A new statement relatingthe ground state components of XXZ spin chains and Temperley-Lieb loop modelsis formulated and proved.


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Input: We analyze the effect of variation of fundamental couplings and mass scaleson primordial nucleosynthesis in a systematic way. The first step establishesthe response of primordial element abundances to the variation of a largenumber of nuclear physics parameters, including nuclear binding energies. Wefind a strong influence of the n-p mass difference (for the 4He abundance), ofthe nucleon mass (for deuterium) and of A=3,4,7 binding energies (for 3He, 6Liand 7Li). A second step relates the nuclear parameters to the parameters of theStandard Model of particle physics. The deuterium, and, above all, 7Liabundances depend strongly on the average light quark mass hat{m} \equiv(m_u+m_d)/2. We calculate the behaviour of abundances when variations offundamental parameters obey relations arising from grand unification. We alsodiscuss the possibility of a substantial shift in the lithium abundance whilethe deuterium and 4He abundances are only weakly affected.


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Input: We investigate colour selection techniques for high redshift galaxies in theUKIDSS Ultra Deep Survey Early Data Release (UDS EDR). Combined with very deepSubaru optical photometry, the depth (K_AB = 22.5) and area (0.62 deg^2) of theUDS EDR allows us to investigate optical/near-IR selection using a large sampleof over 30,000 objects. By using the B-z, z-K colour-colour diagram (the BzKtechnique) we identify over 7500 candidate galaxies at z > 1.4, which can befurther separated into passive and starforming systems (pBzK and sBzKrespectively). Our unique sample allows us to identify a new feature notpreviously seen in BzK diagrams, consistent with the passively evolving trackof early type galaxies at z < 1.4. We also compare the BzK technique with theR-K colour selection of Extremely Red Objects (EROs) and the J-K selection ofDistant Red Galaxies (DRGs), and quantify the overlap between thesepopulations. We find that the majority of DRGs, at these relatively brightmagnitudes are also EROs. Since previous studies have found that DRGs at thesemagnitudes have redshifts of z ~ 1 we determine that these DRG/ERO galaxieshave SEDs consistent with being dusty star-forming galaxies or AGN at z < 2.Finally we observe a flattening in the number counts of pBzK galaxies, similarto other studies, which may indicate that we are sampling the luminosityfunction of passive z > 1 galaxies over a narrow redshift range.


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Input: In this manuscript we investigate the capabilities of the Discrete DipoleApproximation (DDA) to simulate scattering from particles that are much largerthan the wavelength of the incident light, and describe an optimized publiclyavailable DDA computer program that processes the large number of dipolesrequired for such simulations. Numerical simulations of light scattering byspheres with size parameters x up to 160 and 40 for refractive index m=1.05 and2 respectively are presented and compared with exact results of the Mie theory.Errors of both integral and angle-resolved scattering quantities generallyincrease with m and show no systematic dependence on x. Computational timesincrease steeply with both x and m, reaching values of more than 2 weeks on acluster of 64 processors. The main distinctive feature of the computer programis the ability to parallelize a single DDA simulation over a cluster ofcomputers, which allows it to simulate light scattering by very largeparticles, like the ones that are considered in this manuscript. Currentlimitations and possible ways for improvement are discussed.


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Input: This article surveys many standard results about the braid group withemphasis on simplifying the usual algebraic proofs.  We use van der Waerden's trick to illuminate the Artin-Magnus proof of theclassic presentation of the algebraic mapping-class group of a punctured disc.  We give a simple, new proof of the Dehornoy-Larue braid-group trichotomy,and, hence, recover the Dehornoy right-ordering of the braid group.  We then turn to the Birman-Hilden theorem concerning braid-group actions onfree products of cyclic groups, and the consequences derived by Perron-Vannier,and the connections with the Wada representations. We recall the very simpleCrisp-Paris proof of the Birman-Hilden theorem that uses the Larue-Shpilraintechnique. Studying ends of free groups permits a deeper understanding of thebraid group; this gives us a generalization of the Birman-Hilden theorem.Studying Jordan curves in the punctured disc permits a still deeperunderstanding of the braid group; this gave Larue, in his PhD thesis,correspondingly deeper results, and, in an appendix, we recall the essence ofLarue's thesis, giving simpler combinatorial proofs.


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Input: We present a mathematically justifiable, computationally simple, sampleeigenvalue based procedure for estimating the number of high-dimensionalsignals in white noise using relatively few samples. The main motivation forconsidering a sample eigenvalue based scheme is the computational simplicityand the robustness to eigenvector modelling errors which are can adverselyimpact the performance of estimators that exploit information in the sampleeigenvectors.  There is, however, a price we pay by discarding the information in the sampleeigenvectors; we highlight a fundamental asymptotic limit of sample eigenvaluebased detection of weak/closely spaced high-dimensional signals from a limitedsample size. This motivates our heuristic definition of the effective number ofidentifiable signals which is equal to the number of "signal" eigenvalues ofthe population covariance matrix which exceed the noise variance by a factorstrictly greater than 1+sqrt(Dimensionality of the system/Sample size). Thefundamental asymptotic limit brings into sharp focus why, when there are toofew samples available so that the effective number of signals is less than theactual number of signals, underestimation of the model order is unavoidable (inan asymptotic sense) when using any sample eigenvalue based detection scheme,including the one proposed herein. The analysis reveals why adding more sensorscan only exacerbate the situation. Numerical simulations are used todemonstrate that the proposed estimator consistently estimates the true numberof signals in the dimension fixed, large sample size limit and the effectivenumber of identifiable signals in the large dimension, large sample size limit.


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Input: We study Batch Processor-Sharing (BPS) queuing model with hyper-exponentialservice time distribution and Poisson batch arrival process. One of the maingoals to study BPS is the possibility of its application in size-basedscheduling, which is used in differentiation between Short and Long flows inthe Internet. In the case of hyper-exponential service time distribution wefind an analytical expression of the expected conditional response time for theBPS queue. We show, that the expected conditional response time is a concavefunction of the service time. We apply the received results to the Two LevelProcessor-Sharing (TLPS) model with hyper-exponential service time distributionand find the expression of the expected response time for the TLPS model. TLPSscheduling discipline can be applied to size-based differentiation in TCP/IPnetworks and Web server request handling.


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Input: Unconstrained CO2 emission from fossil fuel burning has been the dominantcause of observed anthropogenic global warming. The amounts of "proven" andpotential fossil fuel reserves are uncertain and debated. Regardless of thetrue values, society has flexibility in the degree to which it chooses toexploit these reserves, especially unconventional fossil fuels and thoselocated in extreme or pristine environments. If conventional oil productionpeaks within the next few decades, it may have a large effect on futureatmospheric CO2 and climate change, depending upon subsequent energy choices.Assuming that proven oil and gas reserves do not greatly exceed estimates ofthe Energy Information Administration, and recent trends are toward lowerestimates, we show that it is feasible to keep atmospheric CO2 from exceedingabout 450 ppm by 2100, provided that emissions from coal, unconventional fossilfuels, and land use are constrained. Coal-fired power plants withoutsequestration must be phased out before mid-century to achieve this CO2 limit.It is also important to "stretch" conventional oil reserves via energyconservation and efficiency, thus averting strong pressures to extract liquidfuels from coal or unconventional fossil fuels while clean technologies arebeing developed for the era "beyond fossil fuels". We argue that a rising priceon carbon emissions is needed to discourage conversion of the vast fossilresources into usable reserves, and to keep CO2 beneath the 450 ppm ceiling.


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Input: We present follow-up observations of pulsating subdwarf B (sdB) stars as partof our efforts to resolve the pulsation spectra for use in asteroseismologicalanalyses. This paper reports on multisite campaigns of the pulsating sdB starsPG 1618+563B and PG 0048+091. Data were obtained from observatories placedaround the globe for coverage from all longitudes. For PG 1618+563B, ourfive-site campaign uncovered a dichotomy of pulsation states: Early during thecampaign the amplitudes and phases (and perhaps frequencies) were quitevariable while data obtained late in the campaign were able to fully resolvefive stable pulsation frequencies. For PG 0048+091, our five-site campaignuncovered a plethora of frequencies with short pulsation lifetimes. We findthem to have observed properties consistent with stochastically excitedoscillations, an unexpected result for subdwarf B stars. We discuss ourfindings and their impact on subdwarf B asteroseismology.


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Input: We consider single-file diffusion in an open system with two species $A,B$ ofparticles. At the boundaries we assume different reservoir densities whichdrive the system into a non-equilibrium steady state. As a model we use anone-dimensional two-component simple symmetric exclusion process with twodifferent hopping rates $D_A,D_B$ and open boundaries. For investigating thedynamics in the hydrodynamic limit we derive a system of coupled non-lineardiffusion equations for the coarse-grained particle densities. The relaxationof the initial density profile is analyzed by numerical integration. Exactanalytical expressions are obtained for the self-diffusion coefficients, whichturns out to be length-dependent, and for the stationary solution. In thesteady state we find a discontinuous boundary-induced phase transition as thetotal exterior density gradient between the system boundaries is varied. At oneboundary a boundary layer develops inside which the current flows against thelocal density gradient. Generically the width of the boundary layer and thebulk density profiles do not depend on the two hopping rates. At the phasetransition line, however, the individual density profiles depend strongly onthe ratio $D_A/D_B$. Dynamic Monte Carlo simulation confirm our theoreticalpredictions.


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Input: Extending network lifetime of battery-operated devices is a key design issuethat allows uninterrupted information exchange among distributive nodes inwireless sensor networks. Collaborative beamforming (CB) and cooperativetransmission (CT) have recently emerged as new communication techniques thatenable and leverage effective resource sharing among collaborative/cooperativenodes. In this paper, we seek to maximize the lifetime of sensor networks byusing the new idea that closely located nodes can use CB/CT to reduce the loador even avoid packet forwarding requests to nodes that have critical batterylife. First, we study the effectiveness of CB/CT to improve the signal strengthat a faraway destination using energy in nearby nodes. Then, a 2D disk case isanalyzed to assess the resulting performance improvement. For general networks,if information-generation rates are fixed, the new routing problem isformulated as a linear programming problem; otherwise, the cost for routing isdynamically adjusted according to the amount of energy remaining and theeffectiveness of CB/CT. From the analysis and simulation results, it is seenthat the proposed schemes can improve the lifetime by about 90% in the 2D disknetwork and by about 10% in the general networks, compared to existing schemes.


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Input: We propose a scheme for generating squeezed states in solid state circuitsconsisting of a nanomechanical resonator (NMR), a superconducting Cooper-pairbox (CPB) and a superconducting transmission line resonator (STLR). Thenonlinear interaction between the NMR and the STLR can be implemented bysetting the external biased flux of the CPB at certain values. The interactionHamiltonian between the NMR and the STLR is derived by performing Fr$\rm\ddoto$hlich transformation on the total Hamiltonian of the combined system. Just byadiabatically keeping the CPB at the ground state, we get the standardparametric down-conversion Hamiltonian. The CPB plays the role of ``nonlinearmedia", and the squeezed states of the NMR can be easily generated in a mannersimilar to the three-wave mixing in quantum optics. This is the three-wavemixing in a solid-state circuit.


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Input: Long-lived, heavy particles are predicted in a number of models beyond thestandard model of particle physics. We present the first direct search for suchparticles' decays, occurring up to 100 hours after their production and notsynchronized with an accelerator bunch crossing. We apply the analysis to thegluino (~g), predicted in split supersymmetry, which after hadronization canbecome charged and lose enough momentum through ionization to come to rest indense particle detectors. Approximately 410 pb^-1 of p-pbar collisions at 1.96TeV collected with the D0 detector during Run II of the Fermilab Tevatroncollider are analyzed in search of such ``stopped gluinos'' decaying into agluon and a neutralino (~X_0), reconstructed as a jet and missing energy. Noexcess is observed above background, and limits are placed on the (gluino crosssection) x (probability to stop) x BR(~g -> g ~X_0) as a function of the gluinoand ~X_0 masses, for gluino lifetimes from 30 $\mu$s -- 100 hours.


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Input: In this work we compare numerically exact Quantum Monte Carlo (QMC)calculations and Green function theory (GFT) calculations of thin ferromagneticfilms including second order anisotropies. Thereby we concentrate on easy planesystems, i.e. systems for which the anisotropy favors a magnetization parallelto the film plane. We discuss these systems in perpendicular external field,i.e. B parallel to the film normal. GFT results are in good agreement with QMCfor high enough fields and temperatures. Below a critical field or a criticaltemperature no collinear stable magnetization exists in GFT. On the other handQMC gives finite magnetization even below those critical values. This indicatesthat there occurs a transition from non-collinear to collinear configurationswith increasing field or temperature. For slightly tilted external fields arotation of magnetization from out-of-plane to in-plane orientation is foundwith decreasing temperature.


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Input: The gravitational field of both local and global non static cosmic strings inthe context of Lyra geometry are investigated. Local strings are characterizedby having an energy momentum tensor whose only non null components are $T_{tt}= T_{zz}$ . As linearized Einstein equations are formally analogous to theMaxwell equations, the exterior solution does not depend on the radialdistribution of the source and hence a Dirac d function was used to approximatethe radial distribution of the energy momentum tensor for a local cosmic stringalong the z-axis: $T_{ab} = \delta(x) \delta(y)diag (\sigma, 0, 0, \sigma) $,$\sigma $being the energy density of the string [A.Vilenkin.Phys.Rep.(1985)121,263]. For a global string, the energy momentum tensorcomponents are calculated from the action density for a complex scalar field yalong with a Maxican hat potential. The gravitational field of the globalstring is shown to be attractive in nature.


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Input: In this paper we outline some aspects of nonabelian gauged linear sigmamodels. First, we review how partial flag manifolds (generalizingGrassmannians) are described physically by nonabelian gauged linear sigmamodels, paying attention to realizations of tangent bundles and other aspectspertinent to (0,2) models. Second, we review constructions of Calabi-Yaucomplete intersections within such flag manifolds, and properties of the gaugedlinear sigma models. We discuss a number of examples of nonabelian GLSM's inwhich the Kahler phases are not birational, and in which at least one phase isrealized in some fashion other than as a complete intersection, extendingprevious work of Hori-Tong. We also review an example of an abelian GLSMexhibiting the same phenomenon. We tentatively identify the mathematicalrelationship between such non-birational phases, as examples of Kuznetsov'shomological projective duality. Finally, we discuss linear sigma model modulispaces in these gauged linear sigma models. We argue that the moduli spacesbeing realized physically by these GLSM's are precisely Quot and hyperquotschemes, as one would expect mathematically.


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Input: We investigate the possibility of discriminating between Modified NewtonianDynamics (MOND) and Newtonian gravity with dark matter, by studying thevertical dynamics of disk galaxies. We consider models with the same circularvelocity in the equatorial plane (purely baryonic disks in MOND and the samedisks in Newtonian gravity embedded in spherical dark matter haloes), and weconstruct their intrinsic and projected kinematical fields by solving the Jeansequations under the assumption of a two-integral distribution function. Wefound that the vertical velocity dispersion of deep-MOND disks can be muchlarger than in the equivalent spherical Newtonian models. However, in the morerealistic case of high-surface density disks this effect is significantlyreduced, casting doubts on the possibility of discriminating between MOND andNewtonian gravity with dark matter by using current observations.


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Input: Direct photons provide a insightful tool to study the different stages of aheavy ion collision, especially the formation of a quark-gluon plasma, withoutbeing influenced by the strong interaction and hadronization processes. Theyield of direct photons can be determined based on the inclusive photon yieldand the background from hadronic decays. We present a new analysis techniqueapplied to PHENIX Run4 Au+Au dataset. It uses strict particleidentification(PID) in the Electromagnetic Calorimeter(EMCal) and a chargedparticle veto to extract a clean photon signal. These photons are then taggedwith EMCal photon candidates with loose PID cuts, which can be reconstructedwith high efficiency, to determine the fraction of photons originating from$\pi^{0}$ decays. Many systematic uncertainties and detector effects cancel inthis method.


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Input: Reflectance, transmittance and absorbance of a symmetric light pulse, thecarrying frequency of which is close to the frequency of interband transitionsin a quantum well, are calculated. Energy levels of the quantum well areassumed discrete, and two closely located excited levels are taken intoaccount. A wide quantum well (the width of which is comparable to the length ofthe light wave, corresponding to the pulse carrying frequency) is considered,and the dependance of the interband matrix element of the momentum operator onthe light wave vector is taken into account. Refractive indices of barriers andquantum well are assumed equal each other. The problem is solved for anarbitrary ratio of radiative and nonradiative lifetimes of electronicexcitations. It is shown that the spatial dispersion essentially affects theshapes of reflected and transmitted pulses. The largest changes occur when theradiative broadening is close to the difference of frequencies of interbandtransitions taken into account.


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Input: We study electrical excitation of nonlinear plasma waves in heterostructureswith two-dimensional electron channels and with split gates, and thepropagation of these waves using hydrodynamic equations for electron transportcoupled with two-dimensional Poisson equation for self-consistent electricpotential. The term related to electron collisions with impurities and phononsas well as the term associated with viscosity are included into thehydrodynamic equations. We demonstrate the formation of shock and soliton-likewaves as a result of the evolution of strongly nonuniform initial electrondensity distribution. It is shown that the shock wave front and the shape ofsoliton-like pulses pronouncedly depend on the coefficient of viscosity, thethickness of the gate layer and the nonuniformity of the donor distributionalong the channel. The electron collisions result in damping of the shock andsoliton-like waves, while they do not markedly affect the thickness of theshock wave front.


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Input: We have used Suprime-Cam on the Subaru Telescope to conduct a V- and I-bandimaging survey of fields sampling the spheroid of the Andromeda galaxy alongits south-east minor axis. Our photometric data are deep enough to resolvestars down to the red clump. Based on a large and reliable sample of red giantstars available from this deep wide-field imager, we have derived metallicitydistributions vs. radius and a surface brightness profile over projecteddistances of R=23-66 kpc from the galaxy's center. The metallicitydistributions across this region shows a clear high mean metallicity and abroad distribution ([Fe/H] ~ -0.6 +/- 0.5), and indicates no metallicitygradient within our observed range. The surface brightness profile at R>40 kpcis found to be flatter than previously thought. It is conceivable that thispart of the halo samples as yet unidentified, metal-rich substructure.


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Input: The paper is devoted to classification problem of finite dimensional complexnone Lie filiform Leibniz algebras. Actually, the observations show there aretwo resources to get classification of filiform Leibniz algebras. The first ofthem is naturally graded none Lie filiform Leibniz algebras and the another oneis naturally graded filiform Lie algebras. Using the first resource we get twodisjoint classes of filiform Leibniz algebras. The present paper deals with thesecond of the above two classes, the first class has been considered in ourprevious paper. The algebraic classification here means to specify therepresentatives of the orbits, whereas the geometric classification is theproblem of finding generic structural constants in the sense of algebraicgeometry. Our main effort in this paper is the algebraic classification. Wesuggest here an algebraic method based on invariants. Utilizing this method forany given low dimensional case all filiform Leibniz algebras can be classified.Moreover, the results can be used for geometric classification of orbits ofsuch algebras.


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Input: A general and basic model of primordial evolution--a soup of reactingfinitary and discrete processes--is employed to identify and analyzefundamental mechanisms that generate and maintain complex structures inprebiotic systems. The processes--$\epsilon$-machines as defined incomputational mechanics--and their interaction networks both provide welldefined notions of structure. This enables us to quantitatively demonstratehierarchical self-organization in the soup in terms of complexity. We foundthat replicating processes evolve the strategy of successively building higherlevels of organization by autocatalysis. Moreover, this is facilitated by localcomponents that have low structural complexity, but high generality. In effect,the finitary process soup spontaneously evolves a selection pressure thatfavors such components. In light of the finitary process soup's generality,these results suggest a fundamental law of hierarchical systems: globalcomplexity requires local simplicity.


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Input: We report the recent results of the magnetic transitions and axial-vectortransitions of the baryon antidecuplet within the framework of the chiralquark-soliton model. The dynamical model parameters are fixed by experimentaldata for the magnetic moments of the baryon octet, for the hyperon semileptonicdecay constants, and for the singlet axial-vector constant. The transitionmagnetic moments $\mu_{\Lambda\Sigma}$ and $\mu_{N\Delta}$ are well reproducedand other octet-decuplet and octet-antidecuplet transitions are predicted. Inparticular, the present calculation of $\mu_{\Sigma\Sigma^*}$ is found to bebelow the upper bound $0.82\mu_N$ that the SELEX collaboration measured veryrecently. The results explains consistently the recent findings of a new $N^*$resonance from the GRAAL and Tohoku LNS group. We also obtain the transitionaxial-vector constants for the $\Theta^+\to KN$ from which the decay width ofthe $\Theta^{+}$ pentaquark baryon is determined as a function of thepion-nucleon sigma term $\Sigma_{\pi N}$. We investigate the dependence of thedecay width of the $\Theta^{+}$ on the $g_{A}^{(0)}$, with the $g_{A}^{(0)}$varied within the range of the experimental uncertainty. We show that a smalldecay width of the $\Theta^{+}\to KN$, i.e. $\Gamma_{\Theta KN} \leq 1$ MeV, iscompatible with the values of all known semileptonic decays with the generallyaccepted value of $g_{A}^{(0)} \approx 0.3$ for the proton.


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Input: The bright X-ray transient H 1743-322 was observed daily by the Rossi X-rayTiming Explorer (RXTE) during most of its 8-month outburst in 2003. We presenta detailed spectral analysis and a supporting timing analysis of all of thesedata, and we discuss the behavior and evolution of the source in terms of thethree principal X-ray states defined by Remillard and McClintock. These X-rayresults are complemented by Very Large Array (VLA) data obtained at sixfrequencies that provide quite complete coverage of the entire outburst cycleat 4.860 GHz and 8.460 GHz. We also present photometric data and finding chartsfor the optical counterpart in both outburst and quiescence. We closely compareH 1743-322 to the well-studied black-hole X-ray transient XTE J1550-564 andfind the behaviors of these systems to be very similar. As reported elsewhere,both H 1743-322 and XTE J1550-564 are relativistic jet sources and both exhibita pair of high-frequency QPO oscillations with a 3:2 frequency ratio. The manystriking similarities between these two sources argue strongly that H 1743-322is a black hole binary, although presently no dynamical data exist to supportthis conclusion.