pinecone/core-2020-05-10-deduplication huggingface dataset:
Effective treatment of alkaline Cr(VI) contaminated leachate using a novel Pd-bionanocatalyst : impact of electron donor and aqueous geochemistry

Abstract Palladium catalysts offer the potential for the effective treatment of a variety of priority reducible pollutants in natural waters. In this study, microbially synthesized magnetite nanoparticles were functionalized with Pd(0), creating a highly reactive, magnetically recoverable, nano-scale catalyst (Pd-BnM). This was then investigated for the treatment of model Cr(VI) contaminated solutions at a range of pH values, and also alkaline Cr(VI) contaminated leachates from chromite ore processing residue (COPR); a contaminant issue of global concern. The sample of COPR used in this study was obtained from a site in Glasgow, UK, where extensive Cr(VI) contamination has been reported. In initial experiments Pd-BnM was supplied with H2 gas or formate as electron donors, and Cr(VI) removal from model synthetic solutions was quantified at various pH values (2–12). Effective removal was noted at neutral to environmentally relevant alkaline (pH 12) pH values, while the use of formate as an electron donor resulted in loss of performance under acidic conditions (pH 2). Reaction kinetics were then assessed with increasing Pd-BnM loading in both model pH 12 Cr(VI) solutions and the COPR leachate. When formate was used as the electron donor for Pd-BnM, to treat COPR leachate, there was significant inhibition of Cr(VI) removal. In contrast, a promotion of reaction rate, was observed when H2 was employed. Upon sustained reaction with model Cr(VI) solutions, in the presence of excess electron donor (formate or H2), appreciable quantities of Cr(VI) were removed before eventual inactivation of the catalyst. Faster onset of inactivation was reported in the COPR leachates, removing 4% and 64% of Cr(VI) observed from model Cr(VI) solutions, when formate and H2 were used as electron donors, respectively. XAS, TEM-EDX and XPS analysis of the catalysts that had been inactivated in the model solution, showed that the surface had an extensive covering of reduced Cr(III), most likely as a CrOOH phase. COPR reacted catalysts recorded a lower abundance of Cr(III) alongside a high abundance of the leachate components Ca and Si, implicating these elements in the faster onset of inactivation
Strings from 3D gravity: asymptotic dynamics of AdS$_3$ gravity with
  free boundary conditions

Pure three-dimensional gravity in anti-de Sitter space can be formulated as
an SL(2,R) $\times $ SL(2,R) Chern-Simons theory, and the latter can be reduced
to a WZW theory at the boundary. In this paper we show that AdS$_3$ gravity
with free boundary conditions is described by a string at the boundary whose
target spacetime is also AdS$_3$. While boundary conditions in the standard
construction of Coussaert, Henneaux, and van Driel are enforced through
constraints on the WZW currents, we find that free boundary conditions are
partially enforced through the string Virasoro constraints.Comment: 21 pages; v2: typos corrected, published versio
Pairwise sums in colourings of the reals

Suppose that we have a finite colouring of the reals. What sumset-type
structures can we hope to find in some colour class? One of our aims is to show
that there is such a colouring for which no uncountable set has all of its
pairwise sums monochromatic. We also show that there is such a colouring such
that there is no infinite set X with X+X (the pairwise sums from X, allowing
repetition) monochromatic. These results assume CH. In the other direction, we
show that if each colour class is measurable, or each colour class is Baire,
then there is an infinite set X (and even an uncountable X, of size the reals)
with X+X monochromatic. We also give versions for all of these results for
k-wise sums in place of pairwise sums
The Parzen Window method : in terms of two vectors and one matrix

We thank the BBSRC for funding this research through grant BB/I00596X/1. JBOM thanks the Scottish Universities Life Sciences Alliance (SULSA) for financial support.Pattern classiﬁcation methods assign an object to one of several predeﬁned classes/categories based on features extracted from observed attributes of the object (pattern). When L discriminatory features for the pattern can be accurately determined, the pattern classiﬁcation problem presents no difﬁculty. However, precise identiﬁcation of the relevant features for a classiﬁcation algorithm (classiﬁer) to able to categorize real world patterns without errors is generally infeasible. In this case, the pattern classiﬁcation problem is often cast as devising a classiﬁer that minimises the misclassiﬁcation rate. One way of doing this is to consider both the pattern attributes and its class label as random variables, estimate the posterior class probabilities for a given pattern and then assign the pattern to class/category for which the posterior class probability value estimated is maximum. More often than not, the form of the posterior class probabilities is unknown. The so-called Parzen Window approach is widely employed to estimate class-conditional probability (class-speciﬁc probability) densities a given pattern. These probability densities can then be utilised to estimate the appropriate posterior class probabilities for that pattern. However, the Parzen Window scheme can become computationally impractical when the size of the training dataset is in the tens of thousands and L is also large few hundred or more). Over the years, various schemes have been suggested to ameliorate the computational drawback of the Parzen Window approach, but the problem still remains outstanding and unresolved. In this paper, we revisit the Parzen Window technique and introduce a novel approach that may circumvent the aforementioned computational bottleneck. The current paper presents the mathematical aspect of our idea. Practical realizations of the proposed scheme will be given elsewhere.Publisher PDFPeer reviewe
Regulation of caspase-3 processing by cIAP2 controls the switch between pro-inflammatory activation and cell death in microglia.

The activation of microglia, resident immune cells of the central nervous system, and inflammation-mediated neurotoxicity are typical features of neurodegenerative diseases, for example, Alzheimer's and Parkinson's diseases. An unexpected role of caspase-3, commonly known to have executioner role for apoptosis, was uncovered in the microglia activation process. A central question emerging from this finding is what prevents caspase-3 during the microglia activation from killing those cells? Caspase-3 activation occurs as a two-step process, where the zymogen is first cleaved by upstream caspases, such as caspase-8, to form intermediate, yet still active, p19/p12 complex; thereafter, autocatalytic processing generates the fully mature p17/p12 form of the enzyme. Here, we show that the induction of cellular inhibitor of apoptosis protein 2 (cIAP2) expression upon microglia activation prevents the conversion of caspase-3 p19 subunit to p17 subunit and is responsible for restraining caspase-3 in terms of activity and subcellular localization. We demonstrate that counteracting the repressive effect of cIAP2 on caspase-3 activation, using small interfering RNA targeting cIAP2 or a SMAC mimetic such as the BV6 compound, reduced the pro-inflammatory activation of microglia cells and promoted their death. We propose that the different caspase-3 functions in microglia, and potentially other cell types, reside in the active caspase-3 complexes formed. These results also could indicate cIAP2 as a possible therapeutic target to modulate microglia pro-inflammatory activation and associated neurotoxicity observed in neurodegenerative disorders
An XMM-Newton view of FeKα in high-mass X-ray binaries

We present a comprehensive analysis of the whole sample of available XMM-Newton observations of high-mass X-ray binaries (HMXBs) until August 2013, focusing on the FeKα emission line. This line is key to better understanding the physical properties of the material surrounding the X-ray source within a few stellar radii (the circumstellar medium). We collected observations from 46 HMXBs and detected FeKα in 21 of them. We used the standard classification of HMXBs to divide the sample into different groups. We find that (1) different classes of HMXBs display different qualitative behaviours in the FeKα spectral region. This is visible especially in SGXBs (showing ubiquitous Fe fluorescence but not recombination Fe lines) and in γ Cass analogues (showing both fluorescent and recombination Fe lines). (2) FeKα is centred at a mean value of 6.42 keV. Considering the instrumental and fits uncertainties, this value is compatible with ionization states that are lower than Fe xviii. (3) The flux of the continuum is well correlated with the flux of the line, as expected. Eclipse observations show that the Fe fluorescence emission comes from an extended region surrounding the X-ray source. (4) We observe an inverse correlation between the X-ray luminosity and the equivalent width of FeKα (EW). This phenomenon is known as the X-ray Baldwin effect. (5) FeKα is narrow (σline< 0.15 keV), reflecting that the reprocessing material does not move at high speeds. We attempt to explain the broadness of the line in terms of three possible broadening phenomena: line blending, Compton scattering, and Doppler shifts (with velocities of the reprocessing material V ~ 1000 km s-1). (6) The equivalent hydrogen column (NH) directly correlates to the EW of FeKα, displaying clear similarities to numerical simulations. It highlights the strong link between the absorbing and the fluorescent matter. (7) The observed NH in supergiant X-ray binaries (SGXBs) is in general higher than in supergiant fast X-ray transients (SFXTs). We suggest two possible explanations: different orbital configurations or a different interaction compact object – wind. (8) Finally, we analysed the sources IGR J16320-4751 and 4U 1700-37 in more detail, covering several orbital phases. The observed variation in NH between phases is compatible with the absorption produced by the wind of their optical companions. The results clearly point to a very important contribution of the donor’s wind in the FeKα emission and the absorption when the donor is a supergiant massive star.The work of A.G.G. has been supported by the Spanish MICINN under FPI Fellowship BES-2011-050874 associated to the project AYA2010-15431. This work was supported partially by the Generalitat Valenciana project number GV2014/088 and by the Vicerectorat d’Investigació, Desenvolupament i Innovació de la Universitat d’Alacant under grant GRE12-35. J.J.R.R. acknowledges the support by the Matsumae International Foundation fellowship No14G04
Orbital phase-resolved spectroscopy of 4U 1538−52 with MAXI

Context. 4U 1538−52, an absorbed high mass X-ray binary with an orbital period of ~3.73 days, shows moderate orbital intensity modulations with a low level of counts during the eclipse. Several models have been proposed to explain the accretion at different orbital phases by a spherically symmetric stellar wind from the companion. Aims. The aim of this work is to study both the light curve and orbital phase spectroscopy of this source in the long term. In particular, we study the folded light curve and the changes in the spectral parameters with orbital phase to analyse the stellar wind of QV Nor, the mass donor of this binary system. Methods. We used all the observations made from the Gas Slit Camera on board MAXI of 4U 1538−52 covering many orbits continuously. We obtained the good interval times for all orbital phase ranges, which were the input for extracting our data. We estimated the orbital period of the system and then folded the light curves, and we fitted the X-ray spectra with the same model for every orbital phase spectrum. We also extracted the averaged spectrum of all the MAXI data available. Results. The MAXI spectra in the 2–20 keV energy range were fitted with an absorbed Comptonisation of cool photons on hot electrons. We found a strong orbital dependence of the absorption column density but neither the fluorescence iron emission line nor low energy excess were needed to fit the MAXI spectra. The variation in the spectral parameters over the binary orbit were used to examine the mode of accretion onto the neutron star in 4U 1538−52. We deduce a best value of Ṁ/v∞ = 0.65 × 10-9M⊙ yr-1/ (km s-1) for QV Nor.Part of this work was supported by the Spanish Ministry of Economy and Competitiveness project numbers ESP2013-48637-C2-2P, and ESP2014-53672-C3-3-P, by the Vicerectorat d’Investigació, Desenvolupament i Innovació de la Universitat d’Alacant project number GRE12-35, and by the Generalitat Valenciana project number GV2014/088. This research made use of MAXI data provided by RIKEN, JAXA, and the MAXI team. J.J.R.R. acknowledges the support by the Matsumae International Foundation Research Fellowship No14G04, and also thanks the entire MAXI team for the collaboration and hospitality in RIKEN. The work of A.G.G. has been supported by the Spanish MICINN under FPI Fellowship BES-2011-050874 associated to the project AYA2010-15431. T.M. acknowledges the grant by the Vicerectorat d’Investigació, Desenvolupament i Innovació de la Universitat d’Alacant under visiting researcher programme INV14-11
Measurement of the production cross section of prompt J/ψ mesons in association with a W± boson in pp collisions at √8 = 7 TeV with the ATLAS detector

The process pp ! W±J/  provides a powerful probe of the production mechanism of charmonium in hadronic collisions, and is also sensitive to multiple parton interactions in the colliding protons. Using the 2011 ATLAS dataset of 4.5 fb−1 of p s =7TeV pp collisions at the LHC, the first observation is made of the production of W± +prompt J/  events in hadronic collisions, using W± → μѵμ and Jψ → μ+μ−. A yield of 27.4+7.5−6.5 W± + prompt J/ψ  events is observed, with a statistical significance of 5.1ơ. The production rate as a ratio to the inclusive W± boson production rate is measured, and the double parton scattering contribution to the cross section is estimated
Star formation properties of Universidad Complutense de Madrid survey galaxies

We present new near-infrared J and K imaging data for 67 galaxies from the Universidad Complutense de Madrid (UCM) survey used in the determination of the SFR density of the local Universe by Gallego et al. This is a sample of local star-forming galaxies with redshift lower than 0.045, and they constitute a representative subsample of the galaxies in the complete UCM survey. From the new data, complemented with our own Gunn−r images and long-slit optical spectroscopy, we have measured integrated K-band luminosities, r−J and J−K colours, and Hα luminosities and equivalent widths. Using a maximum likelihood estimator and a complete set of evolutionary synthesis models, these observations allow us to estimate the strength of the current (or most recent) burst of star formation, its age, the star formation rate and the total stellar mass of the galaxies. An average galaxy in the sample has a stellar mass of 5×10^10 M_⊙ and is undergoing (or has recently completed) a burst of star formation involving about 2 per cent of its total stellar mass. We identify two separate classes of star-forming galaxies in the UCM sample: low-luminosity, high-excitation galaxies (HII-like) and relatively luminous spiral galaxies (starburst disk−like). The former show higher specific star formation rates (SFRs per unit mass) and burst strengths, and lower stellar masses than the latter. With regard to their specific star formation rates, the UCM galaxies are intermediate objects between normal quiescent spirals and the most extreme H II galaxies
Exclusive measurements of pd->3HePiPi: The ABC effect revisited

Exclusive measurements of the reactions pd -> He-3 pi(+)7 pi(-) and pd -> He-3 pi(0)pi(0) have been carried out at T-p = 0.893 GeV at the CELSIUS storage ring using the WASA detector. The pi(+)pi(-) channel evidences a pronounced enhancement at low invariant pi pi masses-as anticipated from previous inclusive measurements of the ABC effect. This enhancement is seen to be even much larger in the isoscalar pi(0)pi(0) channel. The differential distributions prove this enhancement to be of scalar-isoscalar nature. Delta Delta calculations give a good description of the data, if a boundstate condition is imposed for the intermediate Delta Delta system. (c) 2006 Elsevier B.V. All fights reserved
Search for the K−pp bound state via γd→K+π−X reaction at Eγ=1.5–2.4GeV

A search for the K−pp bound state (the lightest kaonic nucleus) has been performed using the γd→K+π−X reaction at Eγ=1.5–2.4GeV at LEPS/SPring-8. The differential cross section of the K+π− photo-production off deuterium ( d2σ/dcosθlabK+/dcosθlabπ− ) has been measured for the first time in this energy region. A peak structure was searched for in the inclusive missing mass spectrum. A statistically significant peak structure was not observed in the region from 2.22 to 2.36 GeV/ c 2 . The upper limits of the differential cross section of the K−pp bound state production were determined to be (0.17–0.55), (0.55–1.7) and (1.1–2.9) μb at 95% confidence level with the assumed widths of 20 MeV, 60 MeV and 100 MeV
Flowing from AdS 5 to AdS 3 with T 1 , 1

We construct supersymmetric domain wall solutions of type IIB supergravity that interpolate between AdS 5 × T 1,1 in the UV and AdS 3 × ℝ $$ \mathbb{R} $$ 2 × S 2 × S 3 solutions in the IR. The ℝ $$ \mathbb{R} $$ 2 factor can be replaced with a two-torus and then the solution describes a supersymmetric flow across dimensions, similar to wrapped brane solutions. While the domain wall solutions preserve (0 , 2) supersymmetry, the AdS 3 solutions in the IR have an enhanced (4 , 2) superconformal supersymmetry and are related by two T-dualities to the AdS 3 × S 3 × S 3 × S 1 type IIB solutions which preserve a large (4 , 4) superconformal super-symmetry. The domain wall solutions exist within the N = 4 D = 5 gauged supergravity theory that is obtained from a consistent Kaluza-Klein truncation of type IIB supergravity on T 1,1 ; a feature driving the flows is that two D = 5 axion like fields, residing in the N = 4 Betti multiplet, depend linearly on the two legs of the ℝ $$ \mathbb{R} $$ 2 factor
Testing the FPS approach in d = 1

We apply the approach of S. Ferrara, M. Porrati and A. Sagnotti [1] to the one dimensional system described by the N = 2 , d = 1 supersymmetric action for two particles in which one of N = 1 supersymmetries is spontaneously broken. Using the nonlinear realization approach we reconsider the system in the basis where only one superfield has the Goldstone nature while the second superfield can be treated as the matter one, being invariant under transformations of the spontaneously broken N = 1 supersymmetry. We establish the transformations relating the two selected FPS-like cases with our more general one, and find the field redefinitions which relate these two cases. Thus we demonstrate, at least in one dimension, that the only difference between two FPS cases lies in the different choice of the actions, while the supermultiplets specified by the FPS-like constraints are really the same. Going further with the nonlinear realization approach, we construct the most general action for the system of two N = 1 superfields possessing one additional hidden spontaneously broken N = 1 supersymmetry. The constructed action contains two arbitrary functions and reduces to the FPS actions upon specification of these functions. Unfortunately, the exact form of these functions corresponding to FPS actions is not very informative and gives no explanation on why the FPS cases are selected
Exact spectrum of the spin- s Heisenberg chain with generic non-diagonal boundaries

The off-diagonal Bethe ansatz method is generalized to the high spin integrable systems associated with the su (2) algebra by employing the spin- s isotropic Heisenberg chain model with generic integrable boundaries as an example. With the fusion techniques, certain closed operator identities for constructing the functional T − Q relations and the Bethe ansatz equations are derived. It is found that a variety of inhomogeneous T − Q relations obeying the operator product identities can be constructed. Numerical results for two-site s = 1 case indicate that an arbitrary choice of the derived T − Q relations is enough to give the complete spectrum of the transfer matrix
Photoproduction of ω mesons off the proton

The differential cross sections and unpolarized spin-density matrix elements for the reaction γp→pω were measured using the CBELSA/TAPS experiment for initial photon energies ranging from the reaction threshold to 2.5 GeV. These observables were measured from the radiative decay of the ω meson, ω→π0γ . The cross sections cover the full angular range and show the full extent of the t -channel forward rise. The overall shape of the angular distributions in the differential cross sections and unpolarized spin-density matrix elements are in fair agreement with previous data. In addition, for the first time, a beam of linearly-polarized tagged photons in the energy range from 1150 MeV to 1650 MeV was used to extract polarized spin-density matrix elements
Reproductive history and post-reproductive mortality: a sibling comparison analysis using Swedish register data

A growing body of evidence suggests that reproductive history influences post-reproductive mortality. A potential explanation for this association is confounding by socioeconomic status in the family of origin, as socioeconomic status is related to both fertility behaviours and to long-term health. We examine the relationship between age at first birth, completed parity, and post-reproductive mortality and address the potential confounding role of family of origin. We use Swedish population register data for men and women born 1932-1960, and examine both all-cause and cause-specific mortality. The contributions of our study are the use of a sibling comparison design that minimizes residual confounding from shared family background characteristics and assessment of cause-specific mortality that can shed light on the mechanisms linking reproductive history to mortality. Our results were entirely consistent with previous research on this topic, with teenage first time parents having higher mortality, and the relationship between parity and mortality following a U-shaped pattern where childless men and women and those with five or more children had the highest mortality. These results indicate that selection into specific fertility behaviours based upon socioeconomic status and experiences within the family of origin does not explain the relationship between reproductive history and post-reproductive mortality. Additional analyses where we adjust for other lifecourse factors such as educational attainment, attained socioeconomic status, and post-reproductive marital history do not change the results. Our results add an important new level of robustness to the findings on reproductive history and mortality by showing that the association is robust to confounding by factors shared by siblings. However it is still uncertain whether reproductive history causally influences health, or whether other confounding factors such as childhood health or risk-taking propensity could explain the association