The Ionized Gas and Nuclear Environment in NGC 3783 V. Variability and Modeling of the Intrinsic Ultraviolet Absorption

We present results on the location, physical conditions, and geometry of the outflow in the Seyfert 1 galaxy NGC 3783 from a study of the variable intrinsic UV absorption. Based on 18 observations with HST/STIS and 6 observations with FUSE, we find: 1) The absorption from the lowest-ionization species in each of the three strong kinematic components varied inversely with the continuum flux, indicating the ionization structure responded to changes in the photoionizing flux over the weekly timescales sampled by our observations. 2) A multi- component model with an unocculted NLR and separate BLR and continuum line-of-sight covering factors predicts saturation in several lines, consistent with the lack of observed variability. 3) Column densities for the individual metastable levels are measured from the resolved C III *1175 absorption complex observed in one component. Based on our computed metastable level populations, the electron density of this absorber is ~3x10^4 cm^-3. Photoionization modeling results place it at ~25 pc from the central source. 4) Using time-dependent calculations, we are able to reproduce the detailed variability observed in this absorber, and derive upper limits on the distances for the other components of 25-50 pc. 5) The ionization parameters derived for the higher ionization UV absorbers are consistent with the modeling results for the lowest-ionization X-ray component, but with smaller total column density. They have similar pressures as the three X-ray ionization components. These results are consistent with an inhomogeneous wind model for the outflow in NGC 3783. 6) Based on the predicted emission-line luminosities, global covering factor constraints, and distances derived for the UV absorbers, they may be identified with emission- line gas observed in the inner NLR of AGNs. (abridged)Comment: 30 pages, 18 figures (7 color), emulateapj, accepted for publication in The Astrophysical Journa

The Ionized Gas and Nuclear Environment in NGC 3783. I. Time-Averaged 900 ks Chandra Grating Spectroscopy

We present results from a 900 ks exposure of NGC 3783 with the High-Energy Transmission Grating Spectrometer on board the Chandra X-ray Observatory. The resulting X-ray spectrum has the best combination of signal-to-noise and resolution ever obtained for an AGN. This spectrum reveals absorption lines from H-like and He-like ions of N, O, Ne, Mg, Al, Si, and S. There are also possible absorption lines from H-like and He-like Ar and Ca. We also identify inner-shell absorption from lower-ionization ions such as Si_VII-Si_XII and S_XII-S_XIV. The iron absorption spectrum is very rich; L-shell lines of Fe_XVII-Fe_XXIV are detected, strong complex of M-shell lines, and probable resonance lines from Fe_XXV. The absorption lines are blueshifted relative to the systemic velocity by a mean velocity of -590+-150 km/s. We resolve many of the absorption lines, and their mean FWHM is 820+-280 km/s. We do not find correlations between the velocity shifts or the FWHMs with the ionization potentials of the ions. Most absorption lines show asymmetry, having more extended blue wings than red wings. In O_VII we have resolved this asymmetry to be from an additional absorption system at ~ -1300 km/s. The two X-ray absorption systems are consistent in velocity shift and FWHM with the ones identified in the UV lines of C IV, N V, and H I. Equivalent width measurements for all lines are given and column densities are calculated for several ions. We resolve the narrow Fe_K\alpha line at 6398.2+-3.3 eV to have a FWHM of 1720+-360 km/s, which suggests that this narrow line may be emitted from the outer part of the broad line region or the inner part of the torus. We also detect a `Compton shoulder' redward of the narrow Fe_K\alpha line which indicates that it arises in cold, Compton-thick gas.Comment: 19 pages, 12 figures (2 in color), emulateapj5, accepted for publication in The Astrophysical Journal Supplement

Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars

We present low-resolution ultraviolet spectra of 14 low redshift (z<0.8) quasars observed with HST/STIS as part of a Snap project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the CIV emission line. Nine of the quasars are from the Hamburg-ESO catalog, three are from the Palomar-Green catalog, and one is from the Parkes catalog. The sample contains a few interesting quasars including two broad absorption line (BAL) quasars (HE0143-3535, HE0436-2614), one quasar with a mini-BAL (HE1105-0746), and one quasar with associated narrow absorption (HE0409-5004). These BAL quasars are among the brightest known (though not the most luminous) since they lie at z<0.8. We compare the properties of these BAL quasars to the z1.4 Large Bright Quasar samples. By design, our objects sample luminosities in between these two surveys, and our four absorbed objects are consistent with the v ~ L^0.62 relation derived by Laor & Brandt (2002). Another quasar, HE0441-2826, contains extremely weak emission lines and our spectrum is consistent with a simple power-law continuum. The quasar is radio-loud, but has a steep spectral index and a lobe-dominated morphology, which argues against it being a blazar. The unusual spectrum of this quasar resembles the spectra of the quasars PG1407+265, SDSSJ1136+0242, and PKS1004+13 for which several possible explanations have been entertained.Comment: Uses aastex.cls, 21 pages in preprint mode, including 6 figures and 2 tables; accepted for publication in The Astronomical Journal (projected vol 133

The Ionized Gas and Nuclear Environment in NGC 3783 II. Averaged HST/STIS and FUSE Spectra

We present observations of the intrinsic absorption in the Seyfert 1 galaxy NGC 3783 obtained with the STIS/HST and FUSE. We have coadded multiple STIS and FUSE observations to obtain a high S/N averaged spectrum spanning 905-1730 A. The averaged spectrum reveals absorption in O VI, N V, C IV, N III, C III and the Lyman lines up to LyE in the three blueshifted kinematic components previously detected in the STIS spectrum (at radial velocities of -1320, -724, and -548 km/s). The highest velocity component exhibits absorption in Si IV. We also detect metastable C III* in this component, indicating a high density in this absorber. We separate the individual covering factors of the continuum and emission-line sources as a function of velocity in each kinematic component using the LyA and LyB lines. Additionally, we find that the continuum covering factor varies with velocity within the individual kinematic components, decreasing smoothly in the wings of the absorption by at least 60%. The covering factor of Si IV is found to be less than half that of H I and N V in the high velocity component. Additionally, the FWHM of N III and Si IV are narrower than the higher ionization lines in this component. These results indicate there is substructure within this absorber. We derive a lower limit on the total column (N_H>=10^{19}cm^{-2}) and ionization parameter (U>=0.005) in the low ionization subcomponent of this absorber. The metastable-to-total C III column density ratio implies n_e~10^9 cm^{-3} and an upper limit on the distance of the absorber from the ionizing continuum of R<=8x10^{17} cm.Comment: 29 pages, 8 figures (Figures 1-3 are in color), Accepted for pulication in the Astrophysical Journa

The Core Apoptotic Executioner Proteins CED-3 and CED-4 Promote Initiation of Neuronal Regeneration in Caenorhabditis elegans

Laser severing of individual axons in the nematode Caenorhabditis elegans revealed that the apoptotic executioner caspase CED-3 and its regulator CED-4/Apaf-1 play an unexpected beneficial role in promoting axonal regeneration

Determination of glucose exchange rates and permeability of erythrocyte membrane in preeclampsia and subsequent oxidative stress-related protein damage using dynamic-19F-NMR

The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using 19F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane

A Mouse Model of the Human Fragile X Syndrome I304N Mutation

The mental retardation, autistic features, and behavioral abnormalities characteristic of the Fragile X mental retardation syndrome result from the loss of function of the RNA–binding protein FMRP. The disease is usually caused by a triplet repeat expansion in the 5′UTR of the FMR1 gene. This leads to loss of function through transcriptional gene silencing, pointing to a key function for FMRP, but precluding genetic identification of critical activities within the protein. Moreover, antisense transcripts (FMR4, ASFMR1) in the same locus have been reported to be silenced by the repeat expansion. Missense mutations offer one means of confirming a central role for FMRP in the disease, but to date, only a single such patient has been described. This patient harbors an isoleucine to asparagine mutation (I304N) in the second FMRP KH-type RNA–binding domain, however, this single case report was complicated because the patient harbored a superimposed familial liver disease. To address these issues, we have generated a new Fragile X Syndrome mouse model in which the endogenous Fmr1 gene harbors the I304N mutation. These mice phenocopy the symptoms of Fragile X Syndrome in the existing Fmr1–null mouse, as assessed by testicular size, behavioral phenotyping, and electrophysiological assays of synaptic plasticity. I304N FMRP retains some functions, but has specifically lost RNA binding and polyribosome association; moreover, levels of the mutant protein are markedly reduced in the brain specifically at a time when synapses are forming postnatally. These data suggest that loss of FMRP function, particularly in KH2-mediated RNA binding and in synaptic plasticity, play critical roles in pathogenesis of the Fragile X Syndrome and establish a new model for studying the disorder

Inflammatory biomarkers in Alzheimer's disease plasma

Introduction:Plasma biomarkers for Alzheimer’s disease (AD) diagnosis/stratification are a“Holy Grail” of AD research and intensively sought; however, there are no well-established plasmamarkers.Methods:A hypothesis-led plasma biomarker search was conducted in the context of internationalmulticenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL;259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed.Results:Ten analytes showed significant intergroup differences. Logistic regression identified five(FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APOε4 adjusted, optimally differentiated AD andCTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI(AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Twoanalytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71).Discussion:Plasma markers of inflammation and complement dysregulation support diagnosis andoutcome prediction in AD and MCI. Further replication is needed before clinical translatio

Children’s Emotional Reactivity to Emotionally Evocative Stimuli: Associations With Internalizing Symptoms

Individual differences in emotional reactivity emerge early in development and predict important child outcomes. Unfortunately, methods used to assess these often fail to tap dynamic changes in emotion, obscuring nuanced relationships between maladaptive emotional reactivity and early internalizing psychopathology. We therefore explored the utility of an emerging, multimethod approach for examining children’s emotional reactivity. Thirty-nine children (22 girls; Mage = 7.19 years, SD = .76) viewed 11 video clips eliciting happiness, sadness, or fear. We used multilevel growth curve modeling to estimate change in children’s self-reported and observed emotion across clips of increasing potency. Higher anxious/depressive symptoms predicted steeper trajectories of child-rated happiness and lower happiness and fear toward low-intensity clips. Higher depressive symptoms predicted lower child-rated sadness toward a low-intensity clip. The limited associations between children’s symptoms and emotion ratings averaged across clips suggested that modeling child emotion across stimuli of varying intensity yields a valuable index of emotional reactivity

Development and validation of a battery of emotionally evocative film clips for use with young children

© 2019 American Psychological Association. Investigating normative and maladaptive emotional development requires the ability to elicit children\u27s reactivity to a range of affective stimuli. However, the field lacks a validated battery of stimuli tapping a broad range of childhood emotions. We therefore sought to validate a developmentally appropriate battery of emotionally evocative film stimuli, covering a range of affective responses, for use with children. During pilot work, clips were verified as age appropriate by parents of young children. Next, during a laboratory visit, 39 children (22 girls; Mage = 7.19 years, SD = .76) viewed 20 film clips thought likely to elicit either positive affect, dysphoria (i.e., sadness/anger), or fear, and provided self-reported emotional responses to clips. Children\u27s facial expressions during clips were also rated by trained coders blind to the intended purpose of the clips. We identified clips that successfully elicited the target emotion more so than nontarget emotions according to both coder ratings and child self-report. Implications for the use of these film clips in future research on child emotion are discussed