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The Kupol epithermal Au-Ag vein district is located in the northern part of the Okhotsk-Chukotka volcanic belt, a Late Cretaceous subduction-related continental volcanic arc exposed for >3,000 km along the eastern coast of Russia. High-grade veins are hosted in the Kupol andesite sequence, a 300- to 1,000-m-thick, subhorizontal, layered sequence of andesite flows, sills, and ash tuffs, dated at 97 to 96 Ma (Cenomanian). The Kupol andesite sequence is underlain by mixed mafic-felsic volcanic units plus sedimentary rocks (“older volcanics”) and overlain by a >1-km-thick “upper felsic” sequence of dacitic-rhyolitic tuffs and associated dikes and flow domes, dated at 95 to 85 Ma, with local sequences of fluvio-lacustrine sedimentary rocks. The epithermal veins occupy N-striking, steeply dipping normal faults that cut thick coherent andesite flows and sills in the central-upper part of the Kupol andesite sequence. The district is dominated by the large Kupol vein (180.7 tonnes (t) Au and 1,986 t Ag produced to 2020), hosted by the 5.5-km-long Kupol fault, which accommodates normal, east-side-down displacement of up to 190 m. The Moroshka and Providence veins, 5 km east-southeast of Kupol, occupy shorter faults (1- to 2-km strike) with smaller vertical displacements (to 70 m). The Moroshka vein is dated at 93.5 ± 1.5 Ma (Turonian; 40Ar/39Ar method on adularia), and the timing of vein mineralization here and at Kupol overlaps with the early stage of upper felsic sequence magmatism. Veins contain subhorizontal ore shoots, controlled by the intersection of the steep faults with flat-lying Kupol andesite sequence stratigraphy and by steepening of the faults to a more dilational orientation as the inferred paleosurface is approached. Local structural controls are also evident, reflecting a component of oblique slip on the Kupol fault, with the thickest vein segments at steeply pitching jogs and relays. Main-stage veins grew via repeated encrustation by quartz-chalcedony ± amethyst ± lattice bladed calcite (replaced by quartz), with Au-Ag–bearing crustiform adularia ± clays ± sulfides/sulfosalts/electrum ± chlorite ± hematite bands. The main controls on Au grade are inferred to have been boiling, resulting in sharp vertical limits to high metal grades typical of epithermal veins, coupled with optimal dilation of the vein system where the hosting normal fault steepens near surface with decreasing differential stress. Although much of the displacement on the controlling faults is pre-mineralization in timing, lithified cataclastic breccia, coeval with some vein stages, and vein geometry patterns indicate that some vein development occurred contemporaneously during late normal displacement along the fault system. Waning of the hydrothermal system is marked by late carbonate fill, initially Fe dolomite, then coarse calcite as veins, matrix to vein breccia, and central vein cavity fill. The Kupol district veins have proximal adularia-quartz alteration (haloes meters wide), within an extensive (hundreds of meters in scale) clay alteration halo. Clays are zoned both vertically and laterally with respect to veins, with inner illite-chlorite that was magnetite-destructive (at highest paleotemperature; >220°C), grading outward and upward to illite/interlayered illite-smectite with kaolinite, then to an outer zone (or upper blanket) of smectite, at lowest paleo-temperature (

Photoelectron spectroscopy has long been a powerful method in the toolbox of experimental physical chemistry and molecular physics. Recent improvements in coincidence methods, charged-particle imaging, and electron energy resolution have greatly expanded the variety of environments in which photoelectron spectroscopy can be applied, as well as the range of questions that can now be addressed. In this Perspectives Article, we focus on selected recent studies that highlight these advances and research areas. The topics include reactive intermediates and new thermochemical data, high-resolution comparisons of experiment and theory using methods based on pulsed-field ionisation (PFI), and the application of photoelectron spectroscopy as an analytical tool to monitor chemical reactions in complex environments, like model flames, catalytic or high-temperature reactors.

We present a comparison of the photoionization dynamics of the 4d shell of XeF

Linearly polarized synchrotron radiation has been used to record polarization dependent valence shell photoelectron spectra of imidazole in the photon energy range 21–100 eV. These have allowed the photoelectron angular distributions, as characterized by the anisotropy parameter β, and the electronic state intensity branching ratios to be determined. Complementing these experimental data, theoretical photoionization partial cross sections and β-parameters have been calculated for the outer valence shell orbitals. The assignment of the structure appearing in the experimental photoelectron spectra has been guided by vertical ionization energies and spectral intensities calculated by various theoretical methods that incorporate electron correlation and orbital relaxation. Strong orbital relaxation effects have been found for the 15a′, nitrogen lone-pair orbital. The calculations also predict that configuration mixing leads to the formation of several low-lying satellite states. The vibrational structure associated with ionization out of a particular orbital has been simulated within the Franck–Condon model using harmonic vibrational modes. The adiabatic approximation appears to be valid for the X 2A″ state, with the β-parameter for this state being independent of the level of vibrational excitation. However, for all the other outer valence ionic states, a disparity occurs between the observed and the simulated vibrational structure, and the measured β-parameters are at variance with the behavior expected at the level of the Franck–Condon approximation. These inconsistencies suggest that the excited electronic states may be interacting vibronically such that the nuclear dynamics occur over coupled potential energy surfaces.

We have used the FERMI free-electron laser to perform time-resolved photoelectron imaging experiments on a complex group of resonances near 15.38 eV in the absorption spectrum of molecular nitrogen, N2, under jet-cooled conditions. The new data complement and extend the earlier work of Fushitani et al. [Opt. Express 27, 19702–19711 (2019)], who recorded time-resolved photoelectron spectra for this same group of resonances. Time-dependent oscillations are observed in both the photoelectron yields and the photoelectron angular distributions, providing insight into the interactions among the resonant intermediate states. In addition, for most states, we observe an exponential decay of the photoelectron yield that depends on the ionic final state. This observation can be rationalized by the different lifetimes for the intermediate states contributing to a particular ionization channel. Although there are nine resonances within the group, we show that by detecting individual photoelectron final states and their angular dependence, we can identify and differentiate quantum pathways within this complex system.

The Red Sea, home to the second-longest coral reef system in the world, is a vital resource for the Kingdom of Saudi Arabia. The Red Sea provides 90% of the Kingdom’s potable water by desalinization, supporting tourism, shipping, aquaculture, and fishing industries, which together contribute about 10%–20% of the country’s GDP. All these activities, and those elsewhere in the Red Sea region, critically depend on oceanic and atmospheric conditions. At a time of mega-development projects along the Red Sea coast, and global warming, authorities are working on optimizing the harnessing of environmental resources, including renewable energy and rainwater harvesting. All these require high-resolution weather and climate information. Toward this end, we have undertaken a multipronged research and development activity in which we are developing an integrated data-driven regional coupled modeling system. The telescopically nested components include 5-km- to 600-m-resolution atmospheric models to address weather and climate challenges, 4-km- to 50-m-resolution ocean models with regional and coastal configurations to simulate and predict the general and mesoscale circulation, 4-km- to 100-m-resolution ecosystem models to simulate the biogeochemistry, and 1-km- to 50-m-resolution wave models. In addition, a complementary probabilistic transport modeling system predicts dispersion of contaminant plumes, oil spill, and marine ecosystem connectivity. Advanced ensemble data assimilation capabilities have also been implemented for accurate forecasting. Resulting achievements include significant advancement in our understanding of the regional circulation and its connection to the global climate, development, and validation of long-term Red Sea regional atmospheric–oceanic–wave reanalyses and forecasting capacities. These products are being extensively used by academia, government, and industry in various weather and marine studies and operations, environmental policies, renewable energy applications, impact assessment, flood forecasting, and more. © 2021 American Meteorological Society

We present an experimental and theoretical study of the absorption and emission spectra of Yb atoms in a solid Ne matrix at a resolution of 0.025 nm. Five absorption bands were identified as due to transitions from the $4f^{14}5d^06s^2\ ^1\!S_0$ ground state configuration to $4f^{14}5d^06s6p$ and $4f^{13}5d^16s^2$ configurations. The two lowest energy bands were assigned to outer-shell transitions to $6s6p\ ^3P_1$ and $^1P_1$ atomic states and displayed the structure of a broad doublet and an asymmetric triplet, respectively. The remaining three higher-frequency bands were assigned to inner-shell transitions to distinct $J=1$ states arising from the $4f^{13}5d^16s^2$ configuration and were highly structured with narrow linewidths. A classical simulation was performed to identify the stability and symmetry of possible trapping sites in the Ne crystal. It showed that the overarching 1+2 structure of the high frequency bands could be predominantly ascribed to crystal field splitting in the axial field of a 10-atom vacancy of $C_{4v}$ symmetry. Their prominent substructures were shown to be manifestations of phonon sidebands associated with the zero-phonon lines on each crystal field state. Unprecedented for a metal-rare gas system, resolution of individual phonon states on an allowed electronic transition was possible under excitation spectroscopy which reflects the semi-quantum nature of solid Ne. In contrast to the absorption spectra, emission spectra produced by steady-state excitation into the $^1P_1$ absorption band consisted of simple, unstructured fluorescence bands., Comment: 13 pages, 9 figures

International audience; A double-imaging photoelectron-photoion spectrometer and synchrotron radiation have been used to measure the HBr + X 2 Π 3/2 v + = 0, 1, 2 and the 2 Π 1/2 v + = 0 state photoelectron angular distributions, as characterized by the anisotropy parameter β, the total ion yield, and the threshold photoelectron spectrum. Particular attention has been focussed on the photon energy range between the 2 Π 3/2 and the 2 Π 1/2 spin-orbit components of the ground ionic state. This region encompasses Rydberg states, belonging to series converging onto the upper 2 Π 1/2 ionization limit, which may decay by autoionization into the 2 Π 3/2 ionization continuum. A detailed study has been performed on the effects of autoionization on the 2 Π 3/2 v + = 0 state photoelectron angular distributions. The observed energy dependent variations in the β-values exhibit a regular pattern that correlates with ex-citation into members of a very broad d-type Rydberg series. Additional rapid variations in the β-parameters, which occur over a narrow energy range, appear to coincide with sharp autoionizing Rydberg states belonging to s, p and d series. The present experimental results for the HBr + X 2 Π 3/2 v + = 0 state photoelectron anisotropy parameter are compared to previously reported theoretical predictions and to earlier studies of the Kr + 4p 5 2 P 3/2 state β-parameter. The threshold photoelectron spectrum of the X 2 Π 3/2 v + = 0 band exhibits partially resolved rotational structure. A simulation of this structure yields an ionization threshold of 11.6673 ± 0.0010 eV, which is consistent with previous measurements.

Electronic coherences in molecules are ultrafast charge oscillations on the Molecular Frame MF and their direct observation and separation from electronic population dynamics is challenging. Here we present a valence shell Lab Frame LF scattering method suited to probing electronic coherences in isolated systems. MF electronic coherences lead to LF electronic anisotropies observable by ultrafast angle resolved scattering. Moment analysis of the LF anisotropy completely separates electronic coherences from population dynamics, demonstrated in excited state NH3 using ultrafast time energy angle resolved photoelectron spectroscopy. This general approach applies equally to attosecond femtosecond electronic coherences in isolated systems

Double-resonance excitation of molecular nitrogen, N2, via selected rotational levels of the a′′ 1Σg+, v′ = 0 state has been used to probe the first two bands in the new Ogawa series [M. Ogawa, Can...

Author(s): Nelson, AS; Pratt, RT; Pratt, JD; Smith, RA; Symanski, CT; Prenot, C; Mooney, KA | Abstract: © 2018 The Authors Although species interactions are often proposed to be stronger at lower latitudes and elevations, few studies have evaluated the mechanisms driving such patterns. In this study, we assessed whether, and by which mechanisms, abiotic changes associated with elevation altered the outcome of an ant–aphid protection mutualism. To do so, we characterized the multi-trophic interactions among the ant Formica podzolica, the aphid Aphis varians, and aphid natural enemies occurring on the plant Chamerion angustifolium within replicate high and low elevation valleys. Low (versus high) elevation sites had longer summers (snowmelt 13 days earlier) and were on average 1.1°C warmer and 41% drier throughout the year. At low elevations, individual ant colonies consumed approximately double the volume of carbohydrate baits, likely due to a higher foraging tempo, and possibly due to a greater demand for sugar- versus protein-rich resources (as indicated by stable isotope analysis). Wild aphid colonies at low elevations were visited by 1.4-fold more natural enemies (controlling for variation in aphid abundance), while experimental aphid colonies on potted plants were tended 52% more frequently by ants. As a result, ants increased aphid colony survival by 66% at low elevations but had no detectable effect at high elevations; at low (versus high) elevations aphid colonies without ants had lower survival, demonstrating stronger predator effects, while aphid colonies with ants had higher survival, demonstrating even stronger ant benefits. Analyses for the effects of mean summer temperature yielded qualitatively identical results to those based on elevation. Collectively, these findings support predictions for a greater sensitivity of higher trophic levels to warming and demonstrate how species interactions can vary across environmental gradients due to simultaneous changes in species traits and abundances across multiple trophic levels.

The dynamics of photoabsorption, photoionization, and the associated Auger decay have been investigated at the carbon $K$ edge in methyl iodide ($\mathrm{C}{\mathrm{H}}_{3}\mathrm{I}$) using linearly polarized synchrotron radiation. Ion yield measurements were used to investigate transitions in the pre-edge region due to excitations into either unoccupied valence or Rydberg states. The assignment of these transitions was achieved through comparison with theoretical x-ray absorption spectra calculated using time-dependent density functional theory, within the Tamm-Dancoff approximation. Several of the Rydberg states belonging to series converging onto the $\mathrm{C}1s$ ionization limit exhibit significant vibrational structure that is also interpreted using theoretical calculations. The $\mathrm{C}1s$ in $\mathrm{C}{\mathrm{H}}_{3}\mathrm{I}$ photoelectron spectrum was measured, and the observed vibrational structure was assigned with the aid of theoretical predictions. Polarization dependent, resonantly excited, valence shell photoelectron spectra were recorded at photon energies coinciding with the $\mathrm{C}\phantom{\rule{0.16em}{0ex}}1s\ensuremath{\rightarrow}{\ensuremath{\sigma}}^{*}, \mathrm{C}\phantom{\rule{0.16em}{0ex}}1s\ensuremath{\rightarrow}6s{a}_{1}$ and $\mathrm{C}\phantom{\rule{0.16em}{0ex}}1s\ensuremath{\rightarrow}6pe$ transitions in $\mathrm{C}{\mathrm{H}}_{3}\mathrm{I}$, thereby allowing photoelectron angular distributions to be determined. The nonresonantly excited C(KVV) Auger electron spectrum was measured and some of the features observed at high kinetic energies were attributed to transitions into valence orbitals possessing significant iodine character. The contributions of participator and spectator Auger decay to the resonantly excited photoelectron spectra have been assessed. The influence of participator decay appears minor whereas spectator decay results in the enhanced population of satellite states.

SZ scaling relations have been used to test the self-similar prediction for massive galaxy clusters, but little attention has been given to individual galaxy groups. We investigate the scaling relations of galaxy groups and clusters near the North Ecliptic Pole using X-ray and SZ observations. This region of the sky is where both the ROSAT and Planck satellites achieved their deepest observations, permitting the investigation of lower mass systems. Our sample consists of 62 X-ray detected groups and clusters, spanning a mass range of $10^{13.4}M_{\odot}, Comment: 15 pages, 5 figures, 4 tables, Accepted for publication in the Astrophysical Journal

International audience; The hydroxyl free radical, OH, is one of the most important radicals in atmospheric and interstellar chemistry, and its cation plays a role in the reactions leading to H 2 O formation. Knowledge of the photoionization efficiency of the OH radical is crucial to properly model the water photochemical cycle of atmospheres and astrophysical objects. Using a gas-phase radical source based on a single H-abstraction reaction combined with a photoelectron/photoion imaging coincidence spectrometer coupled with synchrotron radiation, we recorded the OH + photoion yield over the 12.6-15 eV energy range, and we set it to an absolute cross section scale using an absolute point measurement performed at 13.8 eV: σ ion OH = 9.0 ± 2.7 Mb. The resulting cross section values differ by approximately a factor 2 from the recent measurement of Dodson et al. performed with a different radical source is somewhat greater than the combined uncertainties of the measurements. This finding underlines the need for further investigations of this cross section. The hydroxyl radical, OH, is one of the most important free radicals in atmospheric and astrophysical chemistry. It is involved in atmospheric cycles, e.g. as an oxidizing "detergent" on Earth, 1,2 but also in complex photophysical processes in a wide variety of astrophysi-cal media (planetary atmospheres, 3-5 comets, 6 interstel-lar clouds, 7,8 etc.). In these media, OH plays a key role in the water photochemical cycle. The OH + H 2 → H 2 O + H reaction is endothermic, 9 thus most of the reactions involving OH at low temperature occur with O, N, and C atoms and lead to O 2 , NO, and CO compounds rather than H 2 O. On the other hand, the cationic form OH + reacts fast with H 2 , 10 to produce H 2 O + which in turn reacts with H 2 to generate H 3 O +. H 2 O can then be formed through dissociative recombination of H 3 O +. 11 Several theoretical 12 and experimental 13-17 studies have been carried out on the lowest electronic states of neutral OH. However, absorption studies in the Vacuum UltraViolet (VUV) range (λ < 200 nm) are scarce and absolute measurements in this region are even more so. 18,19 For the ionization process, only three experimental works have reported the relative photoionization yield (or constant-ionic-state spectra) of the hydroxyl radical in the VUV range, to our knowledge. 20-23 Dehmer's work covered the photon energy range between 13.0 and 16.5 eV (≈ 95 − 75 nm), at a resolution of 1-3 meV (0.007 − 0.023 nm). 20 Autoionization features were observed in the ion yield and were assigned to a Rydberg series converging to the a + 1 ∆ state of the OH + ion (lo-cated 2.16 eV above the cationic ground state). Later, Cutler et al. carried on Dehmer's work and studied the photoionization of both OH and OD isotopologues between 13.1 and 18.2 eV (94.64-68.12 nm) at a resolution of 1 meV (0.007 nm). 21 They assigned two new Rydberg series converging to the OH + b + 1 Σ + and A + 3 Π ionic states. In 2018, Dodson et al. published the first experimental measurement of the absolute photoionization cross section for OH, where they deduced the cross section from the analysis of time-resolved radical-kinetics measurements of a multi-reaction network in which OH is produced in the reaction of O(1 D) with H 2 O. The absolute cross section of OH was determined relative to that of O(3 P). Their work was supported by new theoretical calculations of the OH cross section using equation-of-motion coupled-cluster Dyson orbitals and a Coulomb photoelectron wave function. 24 The absolute photoionization cross section of the OH radical is important for reliably describing the abundances of OH and OH + and their involvement in the photochemical networks of interstellar media. However, before the work of Dodson et al., modelers could only use the results from theoretical calculations, 12,25,26 or ignore the cross section completely. For instance, the photoion-ization of OH is not present in the Leiden Database 27 or the Meudon PDR code. 28 The new value is expected to find considerable applications in the modeling of atmospheric and interstellar chemistry. Given the importance of this cross section, a complementary experimental determination would also be valuable. We have recently determined the absolute photoion

Vibrational autoionization of Rydberg states provides key information about nonadiabatic processes above an ionization threshold. We employed time-of-flight mass detection of CH3SH+ to record vibrational-state selective photo-ionization efficiency (PIE) spectra of jet-cooled methanethiol (CH3SH) on exciting CH3SH to a specific vibrationally excited state with an infrared (IR) laser, followed by excitation with a tunable laser in the vacuum-ultraviolet (VUV) region for ionization. Autoionizing Rydberg states assigned to the ns, np, nd and nf series are identified. When IR light at 2601 (ν3, SH stretching mode) and 2948 cm−1 (ν2, CH3 symmetric stretching mode) was employed, the Rydberg series converged to the respective vibrationally excited (ν3 and ν2) states of CH3SH+. When IR light at 3014 cm−1 (overlapped ν1/ν9, CH3 antisymmetric stretching and CH2 antisymmetric stretching modes) was employed, Rydberg series converging to two vibrationally excited states (ν1 and ν9) of CH3SH+ were observed. When IR light at 2867 cm−1 (2ν10, overtone of CH3 deformation mode) and 2892 cm−1 (2ν4, overtone of CH2 scissoring mode) was employed, both Δν = −1 and Δν = −2 ionization transitions were observed; there is evidence for direct ionization from the initial state into the CH3SH+ (ν4+ = 1) continuum. In all observed IR-VUV-PIE spectra, the ns and nd series show intensity greater than the other Rydberg series, which is consistent with the fact that the highest-occupied molecular orbital of CH3SH is a p-like lone pair orbital on the S atom. The quantum yields for autoionization of various vibrational excited states are discussed. Values of ν1 = 3035, ν2 = 2884, ν3 = 2514, and ν9 = 2936 cm−1 for CH3SH+ derived from the converged limits agree satisfactorily with values observed for Ar-tagged CH3SH+ at 3026, 2879, 2502, and 2933 cm−1.

International audience; We present new high-resolution data on the photoionization of the 2-butyn-1-yl radical (CH3C≡C–•CH2) formed by H atom abstraction from 2-butyne by F atoms. The spectra were recorded from 7.7 to 11 eV by using double-imaging, photoelectron–photoion coincidence spectroscopy, which allows the unambiguous correlation of photoelectron data and the mass of the species. The photoionization spectrum shows significant resonant autoionizing structure converging to excited states of the C4H5+ cation, similar to what is observed in the closely related propargyl radical (HC≡C–•CH2). The threshold photoelectron spectrum, obtained with a resolution of 17 meV, is also reported. This spectrum is consistent with previous measurements of the first photoionization band but has been extended to higher energy to allow the observation of bands corresponding to excited electronic states of the ion. A refined value of the adiabatic ionization energy is extracted: IE(C4H5) = 7.93 ± 0.01 eV. A determination of the absolute photoionization cross section of the 2-butyn-1-yl radical at 9.7 eV is also reported: σion(C4H5) = 6.1 ± 1.8 Mb.

We present new high-resolution data on the photoionization of the 2-butyn-1-yl radical (CH

8 pags., 5 figs., 4 tabs., The photoelectron spectrum of the XΣ → XΣ ionizing transition of hydrogen isocyanide (HNC) is measured for the first time at a fixed photon energy (13 eV). The assignment of the spectrum is supported by wave-packet calculations simulating the photoionization transition spectrum and using ab initio calculations of the potential energy surfaces for the three lowest electronic states of the cation. The photoelectron spectrum allows the retrieval of the fundamental of the CN stretching mode of the cationic ground state ( = 2260 ± 80 cm) and the adiabatic ionization energy of hydrogen isocyanide: IE(HNC) = 12.011 ± 0.010 eV, which is far below that of HCN (IE(HCN) = 13.607 eV). In light of this latter result, the thermodynamics of the HCN/HNC isomers is discussed and a short summary of the values available in the literature is given., This work received financial support from the French Agence Nationale de la Recherche (ANR) under Grant No. ANR-12-BS08-0020-02 (project SYNCHROKIN) and the CNRS program “Physique et Chimie du Milieu Interstellaire” (PCMI) co-funded by the Centre National d'Etudes Spatiales (CNES). A. A. and O. R. acknowledge support by the Ministerio de Economía e Innovación under grants No. FIS2014-52172-C2 and FIS2017-83473-C2 and from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement no. 610256 (NANOCOSMOS). Work by S. T. P. was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences respectively under contract No. DE-AC02-06CH11357. J.-C. G. thanks the Centre National d'Etudes Spatiales (CNES) for financial support.

Double-resonance excitation of molecular nitrogen, N2, via selected rotational levels of the a′′ 1Σg+, v′ = 0 state has been used to probe the first two bands in the new Ogawa series [M. Ogawa, Can. J. Phys. 42, 1087 (1964)], which lie above the first ionisation threshold of the molecule. These bands are rotationally unresolved in room-temperature and jet-cooled absorption spectra, but the double-resonance technique allows a rotational analysis and first confirmation of the assignment as transitions to n = 4 members of the (A2Πu)ndπ, v Rydberg series. In principle, the probe transition from the a′′ 1Σg+, v = 0 level to these Rydberg states corresponds to a two-electron transition, and this aspect of the results is explored. Finally, velocity map imaging allows a determination of the photoelectron branching fractions and angular distributions, providing insight into the electronic autoionisation dynamics.

Background Inflammatory bowel disease (IBD) is a chronic immune-mediated disease with high impact on nutritional status. Sarcopenia was related to higher risk of intestinal resection and rescue therapy in adult IBD patients; however, data in paediatric population is missing. The aim of this study was to evaluate muscle mass as a predictor of disease outcome in paediatric IBD. Methods All paediatric IBD patients that underwent a magnetic resonance enterography (MRE) study for disease assessment at the Tel Aviv Sourasky Medical Center in 2008–2019 were retrospectively included. Muscle mass was assessed by measuring the area of the psoas muscle at the upper level of L3 on MRE by a freehand region of interest (ROI). Psoas index was defined as the average psoas area divided by body surface area, and then was divided into quartiles. Disease location and radiological signs of IBD were documented. Clinical data including disease activity and course, medications, exacerbations and laboratory results were documented. Results We included 101 patients, 69 (68.3%) Crohn’s disease patients and 32 (31.7%) ulcerative colitis patients. The mean age was 13.05 ± 3.48 years at diagnosis and 15.03 ± 3.27 years at MRE. The psoas index was significantly lower in patients with presence of fatty proliferation (p = 0.021), comb sign (p = 0.001) and extensive disease in MRE (p = 0.012) and in radiologic evidence of disease complications such as abscess or fistula (p = 0.027). In a univariate analysis, patients with psoas index in the lower quartile had significantly higher risk of need for biologic therapy during follow-up (HR = 35.1, p < 0.001; Figure 1) and higher risk of disease exacerbation (HR = 25.1, p < 0.001; Figure 2) compared with patients with psoas index in the upper quartile. In a multivariate analysis adjusted for age, gender, disease type, haemoglobin, C-reactive protein, albumin, disease activity and interval from diagnosis to MRE, patients with psoas index in the lower quartile had significantly higher risk of need for biologic therapy (HR = 12.1, p = 0.046) and of disease exacerbation (HR = 9, p = 0.047) compared with patients with psoas index in the upper quartile. Conclusion Sarcopenia correlates with the radiological severity of IBD and was found to be an independent predictor for severe clinical disease course. Muscle mass in MRE studies may be used as a possible marker for disease outcome in paediatric IBD.

A small survey of the UV-absorbing gas in 12 low-$z$ galaxy groups has been conducted using the Cosmic Origins Spectrograph (COS) on-board the Hubble Space Telescope (HST). Targets were selected from a large, homogeneously-selected sample of groups found in the Sloan Digital Sky Survey (SDSS). A critical selection criterion excluded sight lines that pass close ($, Resubmitted to ApJS after first review; 82 pages (27 for main text, rest are Appendices and supplemental figures and tables), 47 figures, 21 tables

The journal of chemical physics 149(9), 094304 (2018). doi:10.1063/1.5045640, Auger electron spectra following excitation or ionization of the I 3d level in CH$_3$I have been recorded with horizontally or vertically plane polarized synchrotron radiation. These spectra have enabled the Auger electron angular distributions, as characterized by the β parameter, to be determined. The I 3d photoionization partial cross section of CH3I has been calculated with the continuum multiple scattering approach, and the results show that in the photon energy range over which Auger spectra were measured, the I 3d cross section exhibits an atomic-like behavior and is dominated by transitions into the $εf$ continuum channel. In this limit, the theoretical value of the alignment parameter (A$_{20}$) characterizing the core ionized state in an atom becomes constant, independent of photon energy. This theoretical value has been used to obtain the Auger electron intrinsic anisotropy parameters $(α_2)$ from the β parameters extracted from our normal (non-resonant) molecular Auger spectra. The resulting anisotropy parameters for the M45N45N45 transitions in CH3I have been compared to those calculated for the corresponding transitions in xenon, and the experimental and theoretical results are in good agreement. Anisotropy parameters have also been measured for the M$_{45}$N$_1$N$_{45}$, M$_{45}$N$_{23}$N$_{45}$, and M$_{45}$N$_{45}$O$_{23}$ transitions. For the M$_{45}$N$_1$N$_{45}$ and M$_{45}$N$_{23}$N$_{45}$ Auger decays in CH$_3$I, the experimentally derived angular distributions do not exhibit the strong dependence on the final ionic state that is predicted for these transitions in xenon. Resonantly excited Auger spectra have been recorded at 620.4 and 632.0 eV, coinciding with the $I 3d_{5/2} → σ*$ and $3d_{3/2} → σ*$ transitions, respectively. The resulting Auger electron angular distributions for the M$_4$N$_{45}$N$_{45}$ and M$_5$N$_{45}$N$_{45}$ decays were found to exhibit a higher anisotropy than those for the normal process. This is due to the larger photo-induced alignment in the neutral core excited state. For a particular Auger transition, the Auger electron kinetic energy measured in the resonantly excited spectrum is higher than that in the normal spectrum. This shift, due to the screening provided by the electron excited into the $σ*$ orbital, has been rationalized by calculating orbital ionization energies of I 3d excited and I 3d ionized states in CH$_3$I., Published by American Institute of Physics, Melville, NY

To establish the connection between galaxies and UV-detected absorption systems in the local universe, a deep ($g\leq20$) and wide ($\sim20^{\prime}$ radius) galaxy redshift survey is presented around 47 sight lines to UV-bright AGN observed by the Cosmic Origins Spectrograph (COS). Specific COS science team papers have used this survey to connect absorbers to galaxies, groups of galaxies, and large-scale structures, including voids. Here we present the technical details of the survey and the basic measurements required for its use, including redshifts for individual galaxies and uncertainties determined collectively by spectral class (emission-line, absorption-line, and composite spectra) and completeness for each sight line as a function of impact parameter and magnitude. For most of these sight lines the design criteria of $>90$% completeness over a $>1$ Mpc region down to $\lesssim0.1\,L^*$ luminosities at $z\leq0.1$ allows a plausible association between low-$z$ absorbers and individual galaxies. Ly$��$ covering fractions are computed to approximate the star-forming and passive galaxy populations using the spectral classes above. In agreement with previous results, the covering fraction of star-forming galaxies with $L\geq0.3\,L^*$ is consistent with unity inside one virial radius and declines slowly to $>50$% at 4 virial radii. On the other hand, passive galaxies have lower covering fractions ($\sim60$%) and a shallower decline with impact parameter, suggesting that their gaseous halos are patchy but have a larger scale-length than star-forming galaxies. All spectra obtained by this project are made available electronically for individual measurement and use., Accepted by ApJS: 31 pages, 8 figures, 56 tables. The full version of Table 6 can be found at http://casa.colorado.edu/~keeney/documents/galaxy_redshifts.txt [edited to fix broken link], and the individual galaxy spectra can be downloaded from https://archive.stsci.edu/prepds/igm-gal/

Biogenesis of cytochrome c oxidase (CcO), the terminal enzyme of the mitochondrial respiratory chain, is a complex process facilitated by several assembly factors. Pathogenic mutations were recently reported in one such assembly factor, COA6, and our previous work linked Coa6 function to mitochondrial copper metabolism and expression of Cox2, a copper-containing subunit of CcO. However, the precise role of Coa6 in Cox2 biogenesis remained unknown. Here we show that yeast Coa6 is an orthologue of human COA6, and like Cox2, is regulated by copper availability, further implicating it in copper delivery to Cox2. In order to place Coa6 in the Cox2 copper delivery pathway, we performed a comprehensive genetic epistasis analysis in the yeast Saccharomyces cerevisiae and found that simultaneous deletion of Coa6 and Sco2, a mitochondrial copper metallochaperone, or Coa6 and Cox12/COX6B, a structural subunit of CcO, completely abrogates Cox2 biogenesis. Unlike Coa6 deficient cells, copper supplementation fails to rescue Cox2 levels of these double mutants. Overexpression of Cox12 or Sco proteins partially rescues the coa6Δ phenotype, suggesting their overlapping but non-redundant roles in copper delivery to Cox2. These genetic data are strongly corroborated by biochemical studies demonstrating physical interactions between Coa6, Cox2, Cox12 and Sco proteins. Furthermore, we show that patient mutations in Coa6 disrupt Coa6–Cox2 interaction, providing the biochemical basis for disease pathogenesis. Taken together, these results place COA6 in the copper delivery pathway to CcO and, surprisingly, link it to a previously unidentified function of CcO subunit Cox12 in Cox2 biogenesis.

This article announces a new collection of horror and exploitation movies on VHS at Yale University. A brief discussion of Breeders, a movie that Wizard Video released in 1986, demonstrates the type of research the collection is designed to support. Information on the collection’s scope and significance follows, indicating that the holdings also include a number of periodicals, which range from fan publications to industry magazines.

This article reevaluates the significance of buying and reading English play quartos in stab-stitched copies. A survey of more than 2,500 surviving books from the period before 1641 demonstrates that stab-stitching was the dominant choice for short quartos of all forms and genres—not only playbooks and ‘ephemeral’ publications—forcing us to abandon orthodox narratives that use the physical appearance of playbooks as a way to gauge their literary credentials. Poetry by Sidney and Spenser was also sold stab-stitched, and so too were books ranging from humanist classics like More’s Utopia to philosophical treatises written in Latin. Early-modern stab-stitching reminds us that the meaning of bibliographical features is almost always relative, contingent upon book-trade norms and consumer expectations. Playbooks may have been ‘cheap quartos’, but this identity was one that served to connect rather than distance them from other literature.

Ionization of the I 3d, 4s, and 4p orbitals in methyl iodide (CH$_3$I) has been studied by using synchrotron radiation to measure the total ion yield and by recording photoelectron spectra with linearly polarized radiation in two polarization orientations. The complete photoelectron spectrum of CH3I has been recorded at several photon energies, and bands due to the C 1s, I 3d, 4s, 4p, and 4d atomic-like orbitals, as well as the molecular orbitals, have been observed and assigned. In the vicinity of the I 3d5/2 and 3d3/2 ionization thresholds at 626.8 and 638.3 eV, respectively, the ion yield displays weak structure in the pre-edge region due to transitions into valence or Rydberg states, and, at higher energies, a shoulder and a broad maximum attributed to the I 3d$_{5/2} → εf$ and the I 3d$_{3/2} → εf$ shape resonances, respectively. The absorption spectrum calculated using time-dependent density functional theory, within the Tamm-Dancoff approximation, has allowed assignments to be proposed for the valence and Rydberg states. The Stieltjes imaging technique has been used to simulate the absorption spectrum above the ionization threshold and indicates that transitions into the f(l = 3) continuum channel dominate. This conclusion has been corroborated by a Continuum Multiple Scattering–Xα (CMS–Xα) calculation. The asymmetric broadening of the photoelectron bands associated with the I 3d orbital, due to post collision interaction, is taken into account in our experimental analysis. Experimentally derived photoelectron anisotropy parameters for the I 3d orbital are in good agreement with the theoretical predictions obtained with the CMS–Xα approach. The I 3d shake-up/shake-off photoelectron spectrum has been recorded, and assignments have been proposed for several of the satellites. The M$_4$N$_{45}$N$_{45}$ and M$_5$N$_{45}$N$_{45}$ Auger electron yields have been measured, and that for the M$_5$N$_{45}$N$_{45}$ decay exhibits a maximum due to interchannel coupling between the 3d$_{5/2}$ and 3d$_{3/2}$ continua. The photoelectron band associated with the I 4p orbital has an unusual appearance. Based upon previous theoretical work for the analogous Xe 4p orbital, it appears that the initial I 4p$^{−1}$ hole state decays rapidly through Coster-Kronig and super-Coster-Kronig transitions. This leads to a redistribution of the spectral intensity associated with the I 4p orbital and results in a photoelectron spectrum containing a single structured band together with an extended continuum. Another continuum is observed on the high binding energy side of the peak due to the 4s orbital, and we assign this to super-Coster-Kronig transitions into the 4p$^{-1}$4d$^{−1}$ continuum.

The single-photon, photoelectron-photoion coincidence spectrum of N

International audience; The single-photon, photoelectron-photoion coincidence spectrum of N2 has been recorded at high (∼1.5 cm−1) resolution in the region between the N2+ X Σg2+, v+ = 0 and 1 ionization thresholds by using a double-imaging spectrometer and intense vacuum-ultraviolet light from the Synchrotron SOLEIL. This approach provides the relative photoionization cross section, the photoelectron energy distribution, and the photoelectron angular distribution as a function of photon energy. The region of interest contains autoionizing valence states, vibrationally autoionizing Rydberg states converging to vibrationally excited levels of the N2+ X Σg2+ ground state, and electronically autoionizing states converging to the N2+A2Π and B 2Σu+ states. The wavelength resolution is sufficient to resolve rotational structure in the autoionizing states, but the electron energy resolution is insufficient to resolve rotational structure in the photoion spectrum. A simplified approach based on multichannel quantum defect theory is used to predict the photoelectron angular distribution parameters, β, and the results are in reasonably good agreement with experiment

Vibrational autoionization of Rydberg states provides key information about nonadiabatic processes above an ionization threshold. We employed time-of-flight mass detection of CH

The C 1s ionization spectrum of CH3I has been studied both experimentally and theoretically. Synchrotron radiation has been employed to record polarization dependent photoelectron spectra at a photon energy of 614 eV. These spectra encompass the main-line due to the C 1s single-hole state and the peaks associated with the shake-up satellites. Vertical ionization energies and relative photoelectron intensities have been computed using the fourth-order algebraic-diagrammatic construction approximation scheme for the one-particle Green's function and the 6-311++G** basis set. The theoretical spectrum derived from these calculations agrees qualitatively with the experimental results, thereby allowing the principal spectral features to be assigned. According to our calculations, two 2A1 shake-up states of the C 1s-1 σCI → σCI * type with singlet and triplet intermediate coupling of the electron spins (S' = 0, 1) play an important role in the spectrum and contribute significantly to the overall intensity. Both of these states are expected to have dissociative diabatic potential energy surfaces with respect to the C-I separation. Whereas the upper of these states perturbs the manifold of Rydberg states, the lower state forms a band which is characterized by a strongly increased width. Our results indicate that the lowest shake-up peak with significant spectral intensity is due to the pair (S' = 0, 1) of 2E (C 1s-1 I 5p → σCI *) states. We predict that these 2E states acquire photoelectron intensity due to spin-orbit interaction. Such interactions play an important role here due to the involvement of the I 5p orbitals.

We have studied the photodissociation dynamics of anisole (C6H5OCH3) at 193 nm and determined the absolute photoionization cross-section of the phenoxy radical at 118.2 nm (10.486 eV) relative to the known cross-section of the methyl radical. Even at this energy, there is extensive fragmentation of the phenoxy radical upon photoionization, which is attributed to ionizing transitions that populate low-lying excited electronic states of the cation. For phenoxy radicals with less than ∼1 eV of internal energy, we find a cross-section for the production of the phenoxy cation of 14.8 ± 3.8 Mb. For radicals with higher internal energy, dissociative ionization is the dominant process, and for internal energies of ∼2.7-3.7 eV, we find a total cross-section (photoionization plus dissociative ionization) of 22.3 ± 4.1 Mb. The results are discussed relative to the recently reported photoionization cross-section of phenol.

A plant's performance and interactions with other trophic levels are recorgnized to be contingent upon plant diversity and underlying associational dynamics, but far less is known about the plant traits driving such phenomena. We manipulated diversity in plant traits using pairs of plant and a substitutive design to elucidate the mechanisms underlying diversity effects operating at a fine spatial scale. Specifically, we measured the effects of diversity in sex (sexual monocultures vs. male and female genotypes together) and growth rate (growth rate monocultures vs. fast- and slow-growing genotypes together) on growth of the shrub Baccharis salicifolia and on above- and belowground consumers associated with this plant. We compared effects on associate abundance (# associates per plant) vs. density (# associates per kg plant biomass) to elucidate the mechanisms underlying diversity effects; effects on abundance but not density suggest diversity effects are mediated by resource abundance (i.e. plant biomass) alone, whereas effects on density suggest diversity effects are mediated by plant-based heterogeneity or quality. Sexual diversity increased root growth but reduced the density (but not abundance) of the dietary generalist aphid Aphis gossypii and its associated aphid-tending ants, suggesting sex mixtures were of lower quality to this herbivore (e.g. via reduced plant quality), and that this effect indirectly influenced ants. Sexual diversity had no effect on the abundance or density of parasitoids attacking A. gossypii, the dietary specialist aphid Uroleucon macolai, or mycorrhizae. In contrast, growth rate diversity did not influence plant growth or any associates except for the dietary specialist aphid U. macolai, which increased in both abundance and density at high diversity, suggesting growth rate mixtures were of higher quality to this herbivore. These results highlight that plant associational and diversity effects on consumers are contingent upon the source of plant trait variation, and that the nature of such dynamics may vary both within and among trophic levels.

In preparation for a Hubble Space Telescope (HST) observing project using the Cosmic Origins Spectrograph (COS), the positions of all AGN targets having high-S/N far-UV G130M spectra were cross-correlated with a large catalog of low-redshift galaxy groups homogeneously selected from the spectroscopic sample of the Sloan Digital Sky Survey (SDSS). Searching for targets behind only those groups at z = 0.1-0.2 (which places the OVI doublet in the wavelength region of peak COS sensitivity) we identified only one potential S/N = 15-20 target, FBQS 1010+3003. An OVI-only absorber was found in its G130M spectrum at z = 0.11326, close to the redshift of a foreground small group of luminous galaxies at z = 0.11685. Because there is no associated Lyalpha absorption, any characterization of this absorber is necessarily minimal; however, the OVI detection likely traces "warm" gas in collisional ionization equilibrium at T ~ 300,000 K. While this discovery is consistent with being interface gas between cooler, photoionized clouds and a hotter intra-group medium, it could also be warm, interface gas associated with the circum-galactic medium (CGM) of the single closest galaxy. In this case a detailed analysis of the galaxy distribution (complete to 0.2 L*) strongly favors the individual galaxy association. This analysis highlights the necessity of both high-S/N > 20 COS data and a deep galaxy redshift survey of the region in order to test more rigorously the association of OVI-absorbing gas with a galaxy group. A Cycle 23 HST/COS program currently is targeting 10 UV-bright AGN behind 12 low-redshift galaxy groups to test the warm, group gas hypothesis., 11 pages, 3 figures, submitted to ApJ

Despite the importance of sediment transport processes in large rivers, the measurement of sed-iment transport rate in the in-situ, especially bedload, is difficult, costly and time consuming using conven-tional methods. In this paper, a novel indirect bedload estimation methodology is presented that is based on the Acoustic Mapping Velocimetry (AMV). AMV is a combination of acoustic and imaging techniques that provides 2D bedform velocity maps. As such, it can only be used if bedload is represented by bedform migra-tion. This paper illustrates the applicability of the bedload estimation method using as test case a section of the Ohio River in the United States. Repeated measurements of the bathymetry provided by multi-beam echo sounder serve as input data for AMV. Cross-sectional distributions of bedload transport rates obtained with AMV are compared with the estimates provided by another non-intrusive technique, ISSDOTv2, developed by the US Army Corps of Engineers. The good agreement between the results with the two different methods is encouraging and suggests further field tests covering a wider range of hydro-morphological situations.