We investigate the far infrared (IR) spectrum of NGC 1266, a S0 galaxy that contains a massive reservoir of highly excited molecular gas. Using the Herschel Fourier Transform Spectrometer, we detect ...the super(12)CO ladder up to J = (13-12), CI and NII lines, and also strong water lines more characteristic of UltraLuminous IR Galaxies (ULIRGs). The super(12)CO line emission is modeled with a combination of a low-velocity C-shock and a photodissociation region. Shocks are required to produce the H sub(2)O and most of the high-J CO emission. Despite having an IR luminosity 30 times less than a typical ULIRG, the spectral characteristics and physical conditions of the interstellar medium of NGC 1266 closely resemble those of ULIRGs, which often harbor strong shocks and large-scale outflows.
Objective: To describe the systematic analysis of constitutional de novo apparently balanced translocations in patients presenting with abnormal phenotypes, characterise the structural chromosome ...rearrangements, map the translocation breakpoints, and report detectable genomic imbalances. Methods: DNA microarrays were used with a resolution of 1 Mb for the detailed genome-wide analysis of the patients. Array CGH was used to screen for genomic imbalance and array painting to map chromosome breakpoints rapidly. These two methods facilitate rapid analysis of translocation breakpoints and screening for cryptic chromosome imbalance. Breakpoints of rearrangements were further refined (to the level of spanning clones) using fluorescence in situ hybridisation where appropriate. Results: Unexpected additional complexity or genome imbalance was found in six of 10 patients studied. The patients could be grouped according to the general nature of the karyotype rearrangement as follows: (A) three cases with complex multiple rearrangements including deletions, inversions, and insertions at or near one or both breakpoints; (B) three cases in which, while the translocations appeared to be balanced, microarray analysis identified previously unrecognised imbalance on chromosomes unrelated to the translocation; (C) four cases in which the translocation breakpoints appeared simple and balanced at the resolution used. Conclusions: This high level of unexpected rearrangement complexity, if generally confirmed in the study of further patients, will have an impact on current diagnostic investigations of this type and provides an argument for the more widespread adoption of microarray analysis or other high resolution genome-wide screens for chromosome imbalance and rearrangement.
We present ~kiloparsec spatial resolution maps of the CO-to-H2 conversion factor (αCO) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for αCO and the ...DGR by assuming that the DGR is approximately constant on kiloparsec scales. With this assumption, we can combine maps of dust mass surface density, CO-integrated intensity, and H I column density to solve for both αCO and the DGR with no assumptions about their value or dependence on metallicity or other parameters. Such a study has just become possible with the availability of high-resolution far-IR maps from the Herschel key program KINGFISH, 12CO J = (2-1) maps from the IRAM 30 m large program HERACLES, and H I 21 cm line maps from THINGS. We use a fixed ratio between the (2-1) and (1-0) lines to present our αCO results on the more typically used 12CO J = (1-0) scale and show using literature measurements that variations in the line ratio do not affect our results. In total, we derive 782 individual solutions for αCO and the DGR. On average, αCO = 3.1 M ⊙ pc-2 (K km s-1)-1 for our sample with a standard deviation of 0.3 dex. Within galaxies, we observe a generally flat profile of αCO as a function of galactocentric radius. However, most galaxies exhibit a lower αCO value in the central kiloparsec—a factor of ~2 below the galaxy mean, on average. In some cases, the central αCO value can be factors of 5-10 below the standard Milky Way (MW) value of αCO, MW = 4.4 M ⊙ pc-2 (K km s-1)-1. While for αCO we find only weak correlations with metallicity, the DGR is well-correlated with metallicity, with an approximately linear slope. Finally, we present several recommendations for choosing an appropriate αCO for studies of nearby galaxies.
The CII 157.74 mu m transition is the dominant coolant of the neutral interstellar gas, and has great potential as a star formation rate (SFR) tracer. Using the Herschel KINGFISH sample of 46 nearby ...galaxies, we investigate the relation of CII surface brightness and luminosity with SFR. We conclude that CII can be used for measurements of SFR on both global and kiloparsec scales in normal star-forming galaxies in the absence of strong active galactic nuclei (AGNs). The uncertainty of the capital sigma sub(CII) - capital sigma sub(SFR) calibration is + or -0.21 dex. The main source of scatter in the correlation is associated with regions that exhibit warm IR colors, and we provide an adjustment based on IR color that reduces the scatter. We show that the color-adjusted capital sigma sub(CII) - capital sigma sub(SFR) correlation is valid over almost five orders of magnitude in capital sigma sub(SFR), holding for both normal star-forming galaxies and non-AGN luminous infrared galaxies. Using CII luminosity instead of surface brightness to estimate SFR suffers from worse systematics, frequently underpredicting SFR in luminous infrared galaxies even after IR color adjustment (although this depends on the SFR measure employed). We suspect that surface brightness relations are better behaved than the luminosity relations because the former are more closely related to the local far-UV field strength, most likely the main parameter controlling the efficiency of the conversion of far-UV radiation into gas heating. A simple model based on Starburst99 population-synthesis code to connect SFR to CII finds that heating efficiencies are l%-3% in normal galaxies.
We report the measurement of muons and muon-induced phosphorescence in DM-Ice17, a NaI(Tl) direct detection dark matter experiment at the South Pole. Muon interactions in the crystal are identified ...by their observed pulse shape and large energy depositions. The measured muon rate in DM-Ice17 is 2.93+ or -0.04 mu /crystal/day with a modulation amplitude of 12.3+ or -1.7%, consistent with expectation. Following muon interactions, we observe long-lived phosphorescence in the NaI(Tl) crystals with a decay time of 5.5+ or -0.5s. The prompt energy deposited by a muon is correlated to the amount of delayed phosphorescence, the brightest of which consist of tens of millions of photons. These photons are distributed over tens of seconds with a rate and arrival timing that do not mimic a scintillation signal above 2keV sub(ee). While the properties of phosphorescence vary among individual crystals, the annually modulating signal observed by DAMA cannot be accounted for by phosphorescence with the characteristics observed in DM-Ice17.
Stellar density and bar strength should affect the temperatures of the cool (T ~ 20–30 K) dust component in the inner regions of galaxies, which implies that the ratio of temperatures in the ...circumnuclear regions to the disk should depend on Hubble type. We investigate the differences between cool dust temperatures in the central 3 kpc and disk of 13 nearby galaxies by fitting models to measurements between 70 and 500 μm. We attempt to quantify temperature trends in nearby disk galaxies, with archival data from Spitzer/MIPS and new observations with Herschel/SPIRE, which were acquired during the first phases of the Herschel observations for the KINGFISH (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) sample. We fit single-temperature modified blackbodies to far-infrared and submillimeter measurements of the central and disk regions of galaxies to determine the temperature of the component(s) emitting at those wavelengths. We present the ratio of central-region-to-disk-temperatures of the cool dust component of 13 nearby galaxies as a function of morphological type. We find a significant temperature gradient in the cool dust component in all galaxies, with a mean center-to-disk temperature ratio of 1.15 ± 0.03. The cool dust temperatures in the central ~3 kpc of nearby galaxies are 23 (±3)% hotter for morphological types earlier than Sc, and only 9 (±3)% hotter for later types. The temperature ratio is also correlated with bar strength, with only strongly barred galaxies having a ratio over 1.2. The strong radiation field in the high stellar density of a galactic bulge tends to heat the cool dust component to higher temperatures, at least in early-type spirals with relatively large bulges, especially when paired with a strong bar.
New far-infrared and submillimeter photometry from the Herschel Space Observatory is presented for 61 nearby galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel ...(KINGFISH) sample. The spatially integrated fluxes are largely consistent with expectations based on Spitzer far-infrared photometry and extrapolations to longer wavelengths using popular dust emission models. Dwarf irregular galaxies are notable exceptions, as already noted by other authors, as their 500 mu m emission shows evidence for a submillimeter excess. In addition, the fraction of dust heating attributed to intense radiation fields associated with photodissociation regions is found to be (21 + or - 4)% larger when Herschel data are included in the analysis. Dust masses obtained from the dust emission models of Draine & Li are found to be on average nearly a factor of two higher than those based on single-temperature modified blackbodies, as single blackbody curves do not capture the full range of dust temperatures inherent to any galaxy. The discrepancy is largest for galaxies exhibiting the coolest far-infrared colors.
There is limited information about sexual behavior among volunteers who participated in phase I/II human immunodeficiency virus (HIV) vaccine trial. This article describes the sexual behavior, ...practices before, and after participation in phase I/II HIV vaccine trial in Dar es Salaam, Tanzania. We conducted a qualitative descriptive study involving volunteers who participated in the phase I/II vaccine trial between 2007 and 2010. Purposeful sampling was used to recruit potential informants. Twenty-four in-depth interviews were conducted. The audio-recorded interviews were transcribed verbatim and analyzed using a thematic content analysis approach. The findings revealed that before participation in the HIV vaccine trial, informants were engaging in unprotected multiple sexual relationships. After the completion of the HIV vaccine trial, informants reported strengthened marital relationships, increased understanding of safer sexual practices, and HIV testing. However, the informants reported challenges regarding vaccine-induced seropositivity that adversely affected their sexual and marital relationships. Some informants re-engaged in risky sexual practices because they perceived the experimental vaccine was protective. The informants suggested having continued interventions within the community to enhance safer sexual practices. Participation in phase I/II HIV vaccine trials may positively and negatively influence changes in volunteers' sexual behaviors and practices. The trial interventions appear to improve compliance with safer sexual practices. However, the reported vaccine-induced seropositivity and the perception that experimental vaccines are protective need further appropriate interventions.