Far-IR spectroscopy towards Sagittarius B2

The far-IR is a unique wavelength range for Astrophysical studies, however, it can only be fully sampled from space platforms. The fundamental rotational transitions of light molecules, the high-J transitions of polyatomic species, the bending modes of non-polar molecules, several atomic fine structure lines and many frequencies blocked by the earth atmosphere can only be observed between 50 and 200 um (6.0 and 1.5 THz). In this contribution we present the far-IR spectrum of Sgr B2 at a resolution of ~35 km s^{-1}, the ``Rosetta stone'' of ISO's far-IR spectra. We also discuss the perspectives of the far-IR Astronomy in the context of the future telescopes under development.Comment: 4 pages, 2 figures. To appear in the Proceedings of the 4th Cologne-Bonn-Zermatt-Symposium "The Dense Interstellar Medium in Galaxies" eds. S. Pfalzner, C. Kramer, C. Straubmeier, & A. Heithausen (Springer: Berlin

Parallel factor analysis of 4.2K excitation-emission matrices for the direct determination of dibenzopyrene isomers in coal-tar samples with a cryogenic fiber optic probe coupled to a commercial spectrofluorimeter

Several studies have shown high concentrations of polycyclic aromatic hydrocarbons (PAHs) in living spaces and soil adjacent to parking lots sealed with coal-tar-based products. Recent attention has been paid to the presence of seven PAHs in coal-tar samples ? namely, benz[a]anthracene, benzo[k]-fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, chrysene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene ? and their association to significant increases in estimated excess lifetime cancer risk for nearby residents. Herein, we present an analytical approach to screen the presence of five highly toxic, high-molecular weight PAHs (HMW-PAHs) in coal-tar samples. These include dibenzo[a,l]pyrene, dibenzo[a,i]pyrene, dibenzo[a,e]pyrene, dibnezo[a,h]pyrene and naphtho[2,3-a]pyrene. Their direct analysis ? no without chromatographic separation ? - in a reference coal-tar sample is made possible with the combination of excitation-emission matrices (EEMs) and parallel-factor analysis (PARAFAC). EEMs are recorded at 4.2 K with the aid of a cryogenic fiber optic probe and a commercial spectrofluorimeter. The simplicity of the experimental procedure and the excellent analytical figures of merit demonstrate the screening potential of this environmentally friendly approach for the routine analysis of numerous coal-tar samples.Fil: Moore, Anthony F. T.. University of Central Florida; Estados UnidosFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Barbosa, Fernando Jr.. Universidade de Sao Paulo; BrasilFil: Campiglia, Andres D.. University of Central Florida; Estados Unido

Herschel imaging of the dust in the Helix nebula (NGC 7293)

Aims. In our series of papers presenting the Herschel imaging of evolved planetary nebulae, we present images of the dust distribution in the Helix nebula (NGC 7293). / Methods. Images at 70, 160, 250, 350, and 500 μm were obtained with the PACS and SPIRE instruments on board the Herschel satellite. / Results. The broadband maps show the dust distribution over the main Helix nebula to be clumpy and predominantly present in the barrel wall. We determined the spectral energy distribution of the main nebula in a consistent way using Herschel, IRAS, and Planck flux values. The emissivity index of β = 0.99 ± 0.09, in combination with the carbon rich molecular chemistry of the nebula, indicates that the dust consists mainly of amorphous carbon. The dust excess emission from the central star disk is detected at 70 μm and the flux measurement agrees with previous measurement. We present the temperature and dust column density maps. The total dust mass across the Helix nebula (without its halo) is determined to be 3.5 × 10-3 M⊙ at a distance of 216 pc. The temperature map shows dust temperatures between 22 K and 42 K, which is similar to the kinetic temperature of the molecular gas, confirming that the dust and gas co-exist in high density clumps. Archived images are used to compare the location of the dust emission in the far infrared (Herschel) with the ionized (GALEX and Hβ) and molecular (H2) component. The different emission components are consistent with the Helix consisting of a thick walled barrel-like structure inclined to the line of sight. The radiation field decreases rapidly through the barrel wall

Perspective from a Younger Generation -- The Astro-Spectroscopy of Gisbert Winnewisser

Gisbert Winnewisser's astronomical career was practically coextensive with the whole development of molecular radio astronomy. Here I would like to pick out a few of his many contributions, which I, personally, find particularly interesting and put them in the context of newer results.Comment: 14 pages. (Co)authored by members of the MPIfR (Sub)millimeter Astronomy Group. To appear in the Proceedings of the 4th Cologne-Bonn-Zermatt-Symposium "The Dense Interstellar Medium in Galaxies" eds. S. Pfalzner, C. Kramer, C. Straubmeier, & A. Heithausen (Springer: Berlin

Detection of anhydrous hydrochloric acid, HCl, in IRC+10216 with the Herschel SPIRE and PACS spectrometers Detection of HCI in IRC+10216

We report on the detection of anhydrous hydrochloric acid (hydrogen chlorine, HCl) in the carbon-rich star IRC +10216 using the spectroscopic facilities onboard the Herschel satellite. Lines from J = 1–0 up to J = 7–6 have been detected. From the observed intensities, we conclude that HCl is produced in the innermost layers of the circumstellar envelope with an abundance relative to H2 of 5 × 10-8 and extends until the molecules reach its photodissociation zone. Upper limits to the column densities of AlH, MgH, CaH, CuH, KH, NaH, FeH, and other diatomic hydrides have also been obtained

Silicon in the dust formation zone of IRC +10216 as observed with PACS and SPIRE on board Herschel

The interstellar medium is enriched primarily by matter ejected from evolved low and intermediate mass stars. The outflows from these stars create a circumstellar envelope in which a rich gas-phase and dust-nucleation chemistry takes place. We observed the nearest carbon-rich evolved star, IRC+10216, using the PACS (55-210 {\mu}m) and SPIRE (194-672 {\mu}m) spectrometers on board Herschel. We find several tens of lines from SiS and SiO, including lines from the v=1 vibrational level. For SiS these transitions range up to J=124-123, corresponding to energies around 6700K, while the highest detectable transition is J=90-89 for SiO, which corresponds to an energy around 8400K. Both species trace the dust formation zone of IRC+10216, and the broad energy ranges involved in their detected transitions permit us to derive the physical properties of the gas and the particular zone in which each species has been formed. This allows us to check the accuracy of chemical thermodynamical equilibrium models and the suggested depletion of SiS and SiO due to accretion onto dust grains

Herschel spectral mapping of the Helix nebula (NGC 7293): Extended CO photodissociation and OH+ emission

Context. The Helix nebula (NGC 7293) is our closest planetary nebulae. Therefore, it is an ideal template for photochemical studies at small spatial scales in planetary nebulae. Aims. We aim to study the spatial distribution of the atomic and the molecular gas, and the structure of the photodissociation region along the western rims of the Helix nebula as seen in the submillimeter range with Herschel. Methods. We used five SPIRE FTS pointing observations to make atomic and molecular spectral maps. We analyzed the molecular gas by modeling the CO rotational lines using a non-local thermodynamic equilibrium (non-LTE) radiative transfer model. Results. For the first time, we have detected extended OH emission in a planetary nebula. The spectra towards the Helix nebula also show CO emission lines (from J = 4 to 8), [N ii] at 1461 GHz from ionized gas, and [C i] (P- P), which together with the OH lines trace extended CO photodissociation regions along the rims. The estimated OH column density is ~ 10 - 10 cm . The CH (1-0) line was not detected at the sensitivity of our observations. Non-LTE models of the CO excitation were used to constrain the average gas density (n(H) ~ (1 - 5) × 10 cm) and the gas temperature (T ~ 20-40 K). Conclusions. The SPIRE spectral-maps suggest that CO arises from dense and shielded clumps in the western rims of the Helix nebula, whereas OH and [C i] lines trace the diffuse gas and the UV and X-ray illuminated clump surfaces where molecules reform after CO photodissociation. The [N ii] line traces a more diffuse ionized gas component in the interclump medium. © ESO, 2014

Impact of Small Body Weight on Tenofovir-Associated Renal Dysfunction in HIV-Infected Patients: A Retrospective Cohort Study of Japanese Patients

BACKGROUND: Treatment with tenofovir is sometimes associated with renal dysfunction. Limited information is available on this side effect in patients with small body weight, although the use of tenofovir will spread rapidly in Asia and Africa, where patients are likely to be of smaller body weight. METHODS: In a single-center cohort, Japanese patients with HIV infection who started tenofovir-containing antiretroviral therapy were retrospectively analyzed. The incidence of tenofovir-associated renal dysfunction, defined as more than 25% decrement of estimated glomerular filtration rate (eGFR) from the baseline, was determined. The effects of small body weight and body mass index (BMI) on tenofovir-associated renal dysfunction, respectively, were estimated in univariate and multivariate Cox hazards models as the primary exposure. Other possible risk factors were evaluated by univariate analysis and those found significant were entered into the multivariate analysis. RESULTS: The median weight of 495 patients was 63 kg. Tenofovir-related renal dysfunction occurred in 97 (19.6%) patients (incidence: 10.5 per 100 person-years). Univariate analysis showed that the incidence of tenofovir-related renal dysfunction was significantly associated with smaller body weight and BMI, respectively (per 5 kg decrement, HR = 1.23; 95% CI, 1.10-1.37; p<0.001)(per 1 kg/m(2) decrement, HR = 1.14; 95% CI, 1.05-1.23; p = 0.001). Old age, high baseline eGFR, low serum creatinine, low CD4 count, high HIV viral load, concurrent nephrotoxic drugs, hepatitis C infection, and current smoking were also associated with tenofovir-related renal dysfunction. Multivariate analysis identified small body weight as a significant risk (adjusted HR = 1.13; 95% CI, 1.01-1.27; p = 0.039), while small BMI had marginal significance (adjusted HR = 1.07; 95% CI 1.00-1.16; p = 0.058). CONCLUSION: The incidence of tenofovir-associated renal dysfunction in Japanese patients was high. Small body weight was identified as an independent risk factor for tenofovir-associated renal dysfunction. Close monitoring of renal function is advocated for patients with small body weight treated with tenofovir

Crystal structure of a tripartite complex between C3dg, C-terminal domains of factor H and OspE of Borrelia burgdorferi

Complement is an important part of innate immunity. The alternative pathway of complement is activated when the main opsonin, C3b coats non-protected surfaces leading to opsonisation, phagocytosis and cell lysis. The alternative pathway is tightly controlled to prevent autoactivation towards host cells. The main regulator of the alternative pathway is factor H (FH), a soluble glycoprotein that terminates complement activation in multiple ways. FH recognizes host cell surfaces via domains 19–20 (FH19-20). All microbes including Borrelia burgdorferi, the causative agent of Lyme borreliosis, must evade complement activation to allow the infectious agent to survive in its host. One major mechanism that Borrelia uses is to recruit FH from host. Several outer surface proteins (Osp) have been described to bind FH via the C-terminus, and OspE is one of them. Here we report the structure of the tripartite complex formed by OspE, FH19-20 and C3dg at 3.18 Å, showing that OspE and C3dg can bind simultaneously to FH19-20. This verifies that FH19-20 interacts via the “common microbial binding site” on domain 20 with OspE and simultaneously and independently via domain 19 with C3dg. The spatial organization of the tripartite complex explains how OspE on the bacterial surface binds FH19-20, leaving FH fully available to protect the bacteria against complement. Additionally, formation of tripartite complex between FH, microbial protein and C3dg might enable enhanced protection, particularly on those regions on the bacteria where previous complement activation led to deposition of C3d. This might be especially important for slow-growing bacteria that cause chronic disease like Borrelia burgdorferi.Peer reviewe

Depression, Rational Identity and the Educational Imperative: Concordance-Finding in Tricky Diagnostic Moments

It is well-documented, within most medical and much health psychology, that many individuals find diagnoses of depression confusing or even objectionable. Within a corpus of research and practical clinical guidance dominated by the social-cognitive paradigm, the explanation for resistance to a depression diagnosis (or advice pertaining to it) within specific interactions is bordering on the canonical; patients misunderstand depression itself, often as an output of an associated social stigma that distorts public knowledge. The best way to overcome corollary resistance in situ is, logically thus, taken to be a clarification of the true (clinical) nature of depression. In this paper, exploring the diagnosis of depression in UK primary care contexts, the social-cognitive position embedded in contemporary medical reasoning around this matter is critically addressed. It is firstly highlighted how, even in a great deal of extant public health research, the link between an individual holding “correct” medical knowledge and being actively compliant with it is far from inevitable. Secondly, and with respect to concerns around direct communication in clinical contexts, a body of research emergent of Discursive Psychology and Conversation Analysis is explored so as to shed light on how non-cognitive concerns (not least those around the local interactional management of a patient’s social identity) that can inform the manner in which ostensibly “tricky” medical talk plays-out in practice, especially in cases where a mental illness is at stake. Finally, observations are drawn together in a formal Discursive Psychological analysis of a small but highly illustrative sample of three cases where a depression diagnosis is initially questioned or disputed by a patient in primary care but, following further in-consultation activity, concordance with the diagnosis is ultimately reached—a specific issue hitherto unaddressed in either DP or CA fields. These cases specifically reveal the coordinative attention of interlocutors to immediate concerns regarding how the patient might maintain a sense of being an everyday and rational witness to their own lives; indeed, the very act of challenging the diagnosis emerges as a means by which a patient can open up conversational space within the consultation to address such issues. While the veracity of the social-cognitive model is not deemed to be without foundation herein, it is concluded that attention to local interactional concerns might firstly be accorded, such that the practical social concerns and skills of practitioners and patients alike might not be overlooked in the endeavour to produce generally applicable theories