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We present results of a multiwavelength study of the isolated dual AGN system Was 49. Observations show that the dominant component in this interacting system, Was 49a, is a spiral galaxy, while Was 49b is hosted in a dwarf galaxy located at 8 kpc from the nucleus of Was 49a, at the edge of its disk. The intriguing fact about this system is the luminosity of their corresponding AGNs. While Was 49a hosts a low luminosity Seyfert 2 with Lbol˜1043erg s–1, Was 49b has a Seyfert 2 with Lbol ˜ 1045erg s–1, in the luminosity range of Quasars. Furthermore, estimates of the black hole and host galaxy masses of Was 49b indicate a black hole significantly more massive than one would expect from scaling relations. This result is in contrast with findings that the most luminous merger-triggered AGNs are found in major mergers and that minor mergers predominantly enhance AGN activity in the primary galaxy.
We have analyzed Chandra/High Energy Transmission Grating spectra of the X-ray emission line gas in the Seyfert galaxy NGC 4151. The zeroth-order spectral images show extended H- and He-like O and Ne, up to a distance r ˜ 200 pc from the nucleus. Using the 1st-order spectra, we measure an average line velocity ˜230 km s–1, suggesting significant outflow of X-ray gas. We generated Cloudy photoionization models to fit the 1st-order spectra; the fit required three distinct emission-line components. To estimate the total mass of ionized gas (M) and the mass outflow rates, we applied the model parameters to fit the zeroth-order emission-line profiles of Ne IX and Ne X. We determined an M ≍ 5.4 × 105Mʘ. Assuming the same kinematic profile as that for the [O III] gas, derived from our analysis of Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra, the peak X-ray mass outflow rate is approximately 1.8 Mʘ yr–1, at r ˜ 150 pc. The total mass and mass outflow rates are similar to those determined using [O III], implying that the X-ray gas is a major outflow component. However, unlike the optical outflows, the X-ray emitting mass outflow rate does not drop off at r > 100pc, which suggests that it may have a greater impact on the host galaxy.
We present spatially resolved kinematics of ionized gas in the narrow-line region (NLR) and extended narrow-line region (ENLR) in a sample of nearby active galaxies. Utilizing long-slit spectroscopy from Apache Point Observatory (APO)13s ARC 3.5 m Telescope and Hubble Space Telescope (HST) we analyzed the strong λ5007 Å [O III] emission line profiles and mapped the radial velocity distribution of gas at increasing radii from the center. We identified the extents of Active Galactic Nuclei (AGN) driven outflows in our sample and determined the distances at which the observed gas kinematics is being dominated by the rotation of the host galaxy. We also measured the effectiveness of radiative driving of the ionized gas using mass distribution profiles calculated with two-dimensional modeling of surface brightness profiles in our targets. Finally, we compared our kinematic results of the outflow sizes with the maximum distances at which the gas is being radiatively driven to investigate whether these outflows are capable of disrupting or evacuating the star-forming gas at these distances.
We used Space Telescope Imaging Spectrograph (STIS) long slit medium-resolution G430M and G750M spectra to analyze the extended [O III] λ5007 emission in a sample of twelve QSO2s from Reyes et al. (2008). The purpose of the study was to determine the properties of the mass outflows and their role in AGN feedback. We measured fluxes and velocities as functions of deprojected radial distances. Using photoionization models and ionizing luminosities derived from [O III], we were able to estimate the densities for the emission-line gas. From these results, we derived masses, mass outflow rates, kinetic energies and kinetic luminosity rates as a function of radial distance for each of the targets. Masses are several times 103 - 107 solar masses, which are comparable to values determined from a recent photoionization study of Mrk 34 (Revalski). Additionally, we are studying the possible role of X-ray winds in these QSO2s.
We investigate the processes of active galactic nuclei (AGN) feeding and feedback in the narrow line regions (NLRs) and host galaxies of nearby AGN through spatially resolved spectroscopy with the Gemini Near-Infrared Integral Field Spectrograph (NIFS) and the Hubble Space Telescope’s Space Telescope Imaging Spectrograph (STIS). We examine the connection between nuclear and galactic inflows and outflows by adding long-slit spectra of the host galaxies from Apache Point Observatory. We demonstrate that nearby AGN can be fueled by a variety of mechanisms. We find that the NLR kinematics can often be explained by in situ ionization and radiative acceleration of ambient gas, often in the form of dusty molecular spirals that may be the fueling flow to the AGN.
In this review article, we discuss selected developments regarding the role of the equation of state in simulations of core-collapse supernovae. There are no first-principle calculations of the state of matter under supernova conditions since a wide range of conditions is covered, in terms of density, temperature, and isospin asymmetry. Instead, model equation of state are commonly employed in supernova studies. These can be divided into regimes with intrinsically different degrees of freedom: heavy nuclei at low temperatures, inhomogeneous nuclear matter where light and heavy nuclei coexist together with unbound nucleons, and the transition to homogeneous matter at high densities and temperatures. In this article, we discuss each of these phases with particular view on their role in supernova simulations.
Secondary pharmacological interventions have shown promise at reducing the development of posttraumatic stress disorder symptoms (PTSS) in preclinical studies. The present study examined the preliminary efficacy of a 10-day low-dose (20 mg bid) course of hydrocortisone at preventing PTSS in traumatic injury victims.
Sixty-four traumatic injury patients (34% female) were randomly assigned in a double-blind protocol to receive either a 10-day course of hydrocortisone or placebo initiated within 12 hours of the trauma. One-month and 3-months posttrauma participants completed an interview to assess PTSS and self-report measures of depression and health-related quality of life.
Hydrocortisone recipients reported fewer PTSD and depression symptoms, and had greater improvements in health-related quality of life during the first 3 months posttrauma than did placebo recipients. Hydrocortisone recipients who had never received prior mental health treatment had the lowest PTSD scores.
Low-dose hydrocortisone may be a promising approach to the prevention of PTSD in acutely injured trauma patients, and may be particularly efficacious in acutely injured trauma victims without a history of significant psychopathology.
Transbronchial needle aspiration (TBNA) is a technique that has revolutionized the diagnosis of mediastinal pathology by enabling intrathoracic nodal sampling in a minimally invasive manner. The sampling of paratracheal masses using an esophageal varix needle passed through a rigid bronchoscope was initially described by Ko-Pen Wang in 1978. The following year Oho and colleagues created a needle that could be passed through a flexible bronchoscope, thus ushering in a novel modality for sampling intrathoracic lymph nodes without surgical intervention. Over the last 30 years, the technique of TBNA has been relatively unchanged, although the indications for TBNA have expanded to include sampling of hilar lymph nodes, submucosal disease, visible endobronchial lesions, as well as peripheral nodules. The recent development of advanced imaging such as computed tomography (CT) fluoroscopy, electromagnetic navigation, and endobronchial ultrasound (EBUS) now allows real-time visualization of lymph node sampling. Because of these advances, TBNA has emerged as the first line of intrathoracic lymph node sampling for the diagnosis, staging, and prognosis of bronchogenic carcinoma, sarcoidosis, and even infectious diseases.
Bronchogenic carcinoma is the leading cause of cancer death in both men and women in the United States as well as in several other countries. Therapeutic options and prognoses are heavily dependent on accurate staging, and nodal staging is a key component of determining overall clinical stage (Figure 11.1). Non-invasive radiologic staging is suboptimal with sensitivities ranging from 51% to 74%.
Most research on hospital falls has focused on predictors of falling, whereas less is known about predictors of serious fall-related injury. Our objectives were to characterize inpatients who fall and to determine predictors of serious fall-related injury.
We performed a retrospective observational study of 1,082 patients who fell (1,235 falls) during January 2001 to June 2002 at an urban academic hospital. Multivariate analysis of potential risk factors for serious fall-related injury (vs no or minor injury) included in the hospital's adverse event reporting database was conducted with logistic regression to calculate adjusted odds ratios (aORs) with 95% confidence intervals (CI95).
The median age of patients who fell was 62 years (interquartile range, 49-77 years), 50% were women, and 20% were confused. The hospital fall rate was 3.1 falls per 1,000 patient-days, which varied by service from 0.86 (women and infants) to 6.36 (oncology). Some (6.1%) of the falls resulted in serious injury, ranging by service from 3.1% (women and infants) to 10.9% (psychiatry). The most common serious fall-related injuries were bleeding or laceration (53.6%), fracture or dislocation (15.9%), and hematoma or contusion (13%). Patients 75 years or older (aOR, 3.2; CI95, 1.3-8.1) and those on the geriatric psychiatry floor (aOR, 2.8; CI95,1.3-6.0) were more likely to sustain serious fall-related injuries.
There is considerable variation in fall rates and fall-related injury percentages by service. More detailed studies should be conducted by floor or service to identify predictors of serious fall-related injury so that targeted interventions can be developed to reduce them.
Novel materials in which modified inorganic-organic hybrid silica aerogels are attached to polymer chains have been synthesized. The aerogels are based on chitosan, a bioderived polymer from chitin, and they contain silica. The first stage of the modifications includes attachment of isocyanate, amine onto the chitosan chains embedded within the aerogel. These groups are employed in the second stage to develop the reactions required to “string” aerogel particles along functionalized linear polymers or to employ these polymers to crosslink the composite aerogels. The initial chitosan-silica aerogel particles have an ultimate size of about 2nm, and their functionally modified forms were reacted at sizes up to 1 m. These aerogels can take up and hold dyes and water-soluble drugs. The chemistry to synthesize polyamino-siloxane based aerogel composite was discussed. In addition, two approaches to synthesize PHEMA aerogel hybrid were studied.
The mechanical properties of nanoscale volumes and their associated defect structure are key to many future applications in nanoengineered products. In this study, techniques of mechanical testing and microscopy have been applied to better understand the mechanical behavior of nanoscale volumes. Nanoindentation has been used to investigate important mechanical material parameters such as the elastic modulus and hardness for single nanoparticles. New sample preparation methods must be developed to allow the necessary TEM characterization of the inherent and induced defect structure of these nanoparticles. Issues of chemical homogeneity, crystallinity, and defect characteristics at the nanoscale are being addressed in this study. This integration of investigative methods will lead to a greater understanding of the mechanical behavior of nanostructured materials and insights into the nature of defects in materials at the nanoscale.
Nitric oxide (NO) activates soluble guanylyl cyclase (sGC)
and the resulting increase in cyclic guanosine monophosphate
(cGMP) is an important intracellular signalling pathway in the
vertebrate retina. Immunocytochemical detection of cGMP following
exposure to NO donors has proven an effective method of identifying
cells that express sGC. While such an approach has proven useful
for the study of several vertebrate retinas, it has not been
applied to the well-characterized teleost retina. Therefore,
in the present study, we have applied this approach to the retina
of the goldfish (Carassius auratus). In the presence of the
phosphodiesterase (PDE) inhibitor 3-isobutyl-1-methylxanthine (IBMX),
incubation of goldfish eyecups in Ringer's solution containing
(±)-S-nitroso-N-acetylpenicillamine (SNAP) increased
cGMP-like immunoreactivity (cG-ir) in bipolar, horizontal,
amacrine, and ganglion cells and in ganglion cell axons and
optic nerve. Weak labeling was observed in horizontal cells
but no change in cG-ir was noted within photoreceptors. The
NO donor-stimulated increases of cG-ir in horizontal, bipolar,
amacrine, and ganglion cells are consistent with known
physiological effects of NO on these neurons. The physiological
significance of NO action at the level of optic nerve is not
known. The lack of an effect of SNAP on cG-ir in photoreceptors
was unexpected, as there are known physiological actions of
NO, mediated by cGMP, on these neurons. Although this may be
due to insufficient sensitivity of immunolabeling, this result
may indicate a difference between isoforms of sGC or cGMP PDE
in these neurons, compared to neurons where exogenous NO increased
Pharmacological studies have implicated retinal
opiate pathways in the visual regulation of ocular growth.
However, the effects of opiate receptor subtype-specific
compounds on form-deprivation myopia (FDM) are inconsistent
(Seltner et al., 1997), and may be mediated by non-opiate
receptors. The purpose of this study was to test whether
opiate receptor-inactive (D-) enantiomers elicit
the same FDM-suppressing effect as their opiate receptor-active
(L-) counterparts. Since some opiates are thought
to act at NMDA receptors, we also tested whether NMDA receptor
agonists and antagonists influence ocular growth or FDM.
We found that both L- and D- enantiomers
of morphine-like compounds (dextrorphanol and levorphanol,
and D- and L-naloxone) were equally effective
in blocking FDM. The NMDA receptor antagonists dextromethorphan,
MK801, and AP5 also suppressed FDM. A single toxic dose
of NMDA, that destroys many subtypes of amacrine cells
(including those that synthesize the opioid peptide enkephalin),
induced myopia and ocular enlargement in ungoggled eyes,
and eliminated the ability of form-deprivation to enhance
ocular growth. The NR-1 subunit of the NMDA receptor was
localized to a narrowly stratified, intense stratum at
approximately 50% depth in the inner plexiform layer, diffusely
throughout the proximal inner plexiform layer, and to many
somata in the amacrine and ganglion cell layers. These
observations suggest that most effects of opiate receptor
ligands on FDM in the chick are mediated by non-opiate
receptors, which are likely to include NMDA receptors.
NMDA as an excitotoxin transiently enhances ocular growth,
but thereafter disables retinal mechanisms that promote
emmetropization and FDM. These observations are consistent
with a prominent role for pathways utilizing NMDA receptors
in FDM and ocular growth-control.
Sputtered A1N films developed for piezoelectric resonators are extremely chemically reactive. As-sputtered films react with boiling water resulting in a complete loss of the AIN bond structure. Experiments to determine the effect on chemical stability of annealing the sputtered films at 1000 °C, indicate annealing in an oxidizing gas leads to partial oxidation of AlN. Annealing in an inert gas prevents oxidation but does not protect the films from attack by boiling water. Annealing in a reducing gas followed by annealing in an inert gas renders A1N films stable in boiling water. A1N film structure and composition have been studied via Refractive Index, XRD, SIMS, SEM, AES, XPS and FTIR evaluations.
A new method for the preparation of bone samples for δ18O-PO4 analysis has been developed. The phosphate from bone samples is separated and purified using ion exchange chromatography, and then precipitated as silver phosphate using the Firsching method. O2 is then extracted by reaction with bromine pentafluoride and converted to CO2 for isotopic analysis. Advantages of the silver phosphate technique over the bismuth phosphate technique are (1) the simplicity of the method, (2) silver phosphate is not hygroscopic so atmospheric water is not an oxygen contaminate, and (3) very small samples (2 mg to 10 mg) can be analyzed with an increase of precision compared to previous techniques. Iron and silica oxides added to Ag3PO4 standards produce no offset, which suggests that this new technique is not sensitive to interferences from cements commonly found in fossil bone material. Analyses have been performed on standards ranging in size from 30 mg to 2 mg with a σ1 of ± 0.05 per mil.
The δ18O-PO4 compositional pattern of the bones of modern vertebrates have been analyzed to provide a base for the interpretation of the δ18O-PO4 pattern of fossil vertebrates. The average %PO4 in modern mammals and reptiles is approximately 15% with a σ1 of 2-3 %. The average %PO4 of fossil reptiles range from 10 to 25% with σ1 variations of up to 10%. The %PO4 variation can be related to cementation of void spaces in the bone material. XRD analysis reveals that calcite, dolomite, ankerite, and silica cements are commonly present. FTIR (Fourier Transform Infrared Spectroscopy) yields low indices calculated according to the formula of Shemesh, 1990 [GCA 54(9):2433]. Thin sections of the fossil bone material show detailed structures. All this evidence suggests that the fossil bone δ18O-PO4 composition is pristine and not altered by diagenesis. The total δ18O-PO4 σ1 variation of 10 or more skeletal elements analyzed for each individual specimen varies from 0.1 per mil for a domestic cow (Bos) to 0.8 per mil for a Komodo dragon (Varanus). Variations in between appear to be related to thermal physiology and variations in drinking water δ18O due to seasonality or migration.