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Context. The James Webb Space Telescope (JWST) has captured the sharpest infrared images ever taken of the Horsehead nebula, a prototypical moderately irradiated photon-dominated region (PDR) that is fully representative of most of the UV-illuminated molecular gas in the Milky Way and star-forming galaxies. Aims. We investigate the impact of far-ultraviolet (FUV) radiation emitted by a massive star on the edge of a molecular cloud in terms of photoevaporation, ionization, dissociation, H2 excitation, and dust heating. We also aim to constrain the structure of the edge of the PDR and its illumination conditions. Methods. We used NIRCam and MIRI to obtain 17 broadband and 6 narrowband maps of the illuminated edge of the Horsehead across a wide spectral range from 0.7 to 28 µm. We mapped the dust emission, including the aromatic and aliphatic infrared (IR) bands, scattered light, and several gas phase lines (e.g., Paa, Brα, H2 1-0 S(1) at 2.12 µm). For our analysis, we also associated two HST-WFC3 maps at 1.1 and 1.6 µm, along with HST-STIS spectroscopic observations of the Ha line. Results. We probed the structure of the edge of the Horsehead and resolved its spatial complexity with an angular resolution of 0.1 to 1″ (equivalent to 2 × 10−4 to 2 × 10−3 pc or 40 to 400 au at the distance of 400 pc). We detected a network of faint striated features extending perpendicularly to the PDR front into the HII region in NIRCam and MIRI filters sensitive to nano-grain emission, as well as in the HST filter at 1.1 µm, which traces light scattered by larger grains. This may indeed figure as the first detection of the entrainment of dust particles in the evaporative flow. The filamentary structure of the 1-0 S(1) line of H2 at the illuminated edge of the PDR presents numerous sharp sub-structures on scales as small as 1.5″. An excess of H2 emission compared to dust emission is found all along the edge, in a narrow layer (width around 1″, corresponding to 2 × 10−3 pc or 400 au) directly illuminated by σ-Orionis. The ionization front and the dissociation front appear at distances 1–2″ behind the external edge of the PDR and seem to spatially coincide, indicating a very small thickness of the neutral atomic layer (below 100 au). All broadband maps present strong color variations between the illuminated edge and the internal regions. This can be explained by dust attenuation in a scenario where the illuminating star σ-Orionis is slightly inclined compared to the plane of the sky, so that the Horsehead is illuminated from behind at an oblique angle. The deviations from predictions of the measured emissions in the Hα, Paα, and Brα lines also indicate dust attenuation. With a very simple model, we used the data to derive the main spectral features of the extinction curve. A small excess of extinction at 3 µm may be attributed to icy H2O mantles onto grains formed in dense regions. We also derived attenuation profiles from 0.7 to 25 µm across the PDR. In all lines of sight crossing the inner regions of the Horsehead, especially around the IR peak position, it appears that dust attenuation is non-negligible over the entire spectral range of the JWST. [ABSTRACT FROM AUTHOR]

We present deep far-infrared observations of the nearby edge-on galaxy NGC 891 obtained with the Herschel Space Observatory and the Spitzer Space Telescope. The maps confirm the detection of thermal emission from the inner circumgalactic medium (halo) and spatially resolve a dusty superbubble and a dust spur (filament). The dust temperature of the halo component is lower than that of the disc but increases across a region of diameter ≈8.0 kpc extending at least 7.7 kpc vertically from one side of the disc, a region we call a superbubble because of its association with thermal X-ray emission and a minimum in the synchrotron scale height. This outflow is breaking through the thick disc and developing into a galactic wind, which is of particular interest because NGC 891 is not considered a starburst galaxy; the star formation rate surface density, 0.03 M⊙ yr−1 kpc−2, and gas fraction, just |$10{{\ \rm per\ cent}}$| in the inner disc, indicate the threshold for wind formation is lower than previous work has suggested. We conclude that the star formation surface density is sufficient for superbubble blowout into the halo, but the cosmic ray electrons may play a critical role in determining whether this outflow develops into a fountain or escapes from the gravitational potential. The high dust-to-gas ratio in the dust spur suggests the material was pulled out of NGC 891 through the collision of a minihalo with the disc of NGC 891. We conclude that NGC 891 offers an example of both feedback and satellite interactions transporting dust into the halo of a typical galaxy. [ABSTRACT FROM AUTHOR]

We have fit the far-ultraviolet (FUV) to sub-millimeter (850 μm) spectral energy distributions (SEDs) of the 61 galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel (KINGFISH). The fitting has been performed using three models: the Code for Investigating GALaxy Evolution (CIGALE), the GRAphite-SILicate approach (GRASIL), and the Multiwavelength Analysis of Galaxy PHYSical properties (MAGPHYS). We have analyzed the results of the three codes in terms of the SED shapes, and by comparing the derived quantities with simple "recipes" for stellar mass (Mstar), star-formation rate (SFR), dust mass (Mdust), and monochromatic luminosities. Although the algorithms rely on different assumptions for star-formation history, dust attenuation and dust reprocessing, they all well approximate the observed SEDs and are in generally good agreement for the associated quantities. However, the three codes show very different behavior in the mid-infrared regime: in the 5–10 μm region dominated by PAH emission, and also between 25 and 70 μm where there are no observational constraints for the KINGFISH sample. We find that different algorithms give discordant SFR estimates for galaxies with low specific SFR, and that the standard recipes for calculating FUV absorption overestimate the extinction compared to the SED-fitting results. Results also suggest that assuming a "standard" constant stellar mass-to-light ratio overestimates Mstar relative to the SED fitting, and we provide new SED-based formulations for estimating Mstar from WISE W1 (3.4 μm) luminosities and colors. From a principal component analysis of Mstar, SFR, Mdust, and O/H, we reproduce previous scaling relations among Mstar, SFR, and O/H, and find that Mdust can be predicted to within ∼0.3 dex using only Mstar and SFR. [ABSTRACT FROM AUTHOR]

Context. The radiative transport of photons through arbitrary three-dimensional (3D) structures of dust is a challenging problem due to the anisotropic scattering of dust grains and strong coupling between different spatial regions. The radiative transfer problem in 3D is solved using Monte Carlo or Ray Tracing techniques as no full analytic solution exists for the true 3D structures. Aims. We provide the first 3D dust radiative transfer benchmark composed of a slab of dust with uniform density externally illuminated by a star. This simple 3D benchmark is explicitly formulated to provide tests of the different components of the radiative transfer problem including dust absorption, scattering, and emission. Methods. The details of the external star, the slab itself, and the dust properties are provided. This benchmark includes models with a range of dust optical depths fully probing cases that are optically thin at all wavelengths to optically thick at most wavelengths. The dust properties adopted are characteristic of the diffuse Milky Way interstellar medium. This benchmark includes solutions for the full dust emission including single photon (stochastic) heating as well as two simplifying approximations: One where all grains are considered in equilibrium with the radiation field and one where the emission is from a single effective grain with size-distribution averaged properties. A total of six Monte Carlo codes and one Ray Tracing code provide solutions to this benchmark. Results. The solution to this benchmark is given as global spectral energy distributions (SEDs) and images at select diagnostic wavelengths from the ultraviolet through the infrared. Comparison of the results revealed that the global SEDs are consistent on average to a few percent for all but the scattered stellar flux at very high optical depths. The image results are consistent within 10%, again except for the stellar scattered flux at very high optical depths. The lack of agreement between different codes of the scattered flux at high optical depths is quantified for the first time. Convergence tests using one of the Monte Carlo codes illustrate the sensitivity of the solutions to various model parameters. Conclusions. We provide the first 3D dust radiative transfer benchmark and validate the accuracy of this benchmark through comparisons between multiple independent codes and detailed convergence tests. [ABSTRACT FROM AUTHOR]

We present Spitzer/Infrared Spectrograph (IRS) 5-21 µm spectroscopic maps towards 12 regions in the Andromeda galaxy (M31). These regions include the nucleus, bulge, an active region in the star-forming ring and nine other regions chosen to cover a range of mid-to-far-infrared colours. In line with previous results, polycyclic aromatic hydrocarbon (PAH) feature ratios (6.2 and 7.7 µm features compared to the 11.2 µm feature) measured from our extracted M31 spectra, except the nucleus, strongly correlate. The equivalent widths of the main PAH features, as a function of metallicity and radiation hardness, are consistent with those observed for other nearby spiral and starburst galaxies. Reprocessed data from the ISOCAM instrument on the Infrared Space Observatory agree with the IRS data; early reports of suppressed 6-8 µm features and enhanced 11.3 µm feature intensity and full width at half-maximum apparently resulted from background-subtraction problems. The nucleus does not show any PAH emission but does show strong silicate emission at 9.7 µm. Furthermore, different spectral features (11.3 µm PAH emission, silicate emission and [Ne III] 15.5 µm line emission) have distinct spatial distributions in the nuclear region: the silicate emission is strongest towards the stellar nucleus, while the PAH emission peaks 15 arcsec north of the nucleus. The PAH feature ratios at this position are atypical with strong emission at 11.2 and 15-20 µm but weak emission at 6-8 µm. The nucleus itself is dominated by stellar light giving rise to a strong blue continuum and silicate emission. [ABSTRACT FROM AUTHOR]

Previous studies of the mechanical properties of tendons in the upper limb have used embalmed specimens or sub-optimal methods of measurement. The aim of this study was to determine the biomechanical properties of all tendons from five fresh frozen cadaveric forearms using updated methodology. The cross-sectional area of tendons was accurately measured using a laser reflectance system. Tensile testing was done in a precision servo-hydraulic device with cryo-clamp fixation. We determined that the cross-sectional area of some tendons is variable and directly influences the calculated material properties; visual estimation of this is unreliable. Data trends illustrate that digital extensor tendons possess the greatest tensile strength and a higher Young’s modulus than other tendon types. [ABSTRACT FROM AUTHOR]

We present the detection and analysis of molecular hydrogen emission towards ten interstellar regions in the Large Magellanic Cloud. We examined low-resolution infrared spectral maps of 12 regions obtained with the Spitzer infrared spectrograph (IRS). The pure rotational 0-0 transitions of H2 at 28.2 and 17.1 μm are detected in the IRS spectra for 10 regions. The higher level transitions are mostly upper limit measurements except for three regions, where a 3σ detection threshold is achieved for lines at 12.2 and 8.6 μm. The excitation diagrams of the detected H2 transitions are used to determine the warm H2 gas column density and temperature. The single-temperature fits through the lower transition lines give temperatures in the range 86-137 K. The bulk of the excited H2 gas is found at these temperatures and contributes ~5-17 per cent to the total gas mass. We find a tight correlation of the H2 surface brightness with polycyclic aromatic hydrocarbon and total infrared emission, which is a clear indication of photoelectric heating in photodissociation regions. We find the excitation of H2 by this process is equally efficient in both atomic- and molecular-dominated regions. We also present the correlation of the warm H2 physical conditions with dust properties. The warm H2 mass fraction and excitation temperature show positive correlations with the average starlight intensity, again supporting H2 excitation in photodissociation regions. [ABSTRACT FROM AUTHOR]

Context. Edge-on spiral galaxies with prominent dust lanes provide us with an excellent opportunity to study the distribution and properties of the dust within them. The HEROES project was set up to observe a sample of seven large edge-on galaxies across various wavelengths for this investigation. Aims. Within this first paper, we present the Herschel observations and perform a qualitative and quantitative analysis on them, and we derive some global properties of the far infrared and submillimetre emission. Methods. We determine horizontal and vertical profiles from the Herschel observations of the galaxies in the sample and describe the morphology. Modified black-body fits to the global fluxes, measured using aperture photometry, result in dust temperatures and dust masses. The latter values are compared to those that are derived from radiative transfer models taken from the literature. Results. On the whole, our Herschel flux measurements agree well with archival values. We find that the exponential horizontal dust distribution model often used in the literature generally provides a good description of the observed horizontal profiles. Three out of the seven galaxies show signatures of extended vertical emission at 100 and 160 μm at the 5σ level, but in two of these it is probably due to deviations from an exactly edge-on orientation. Only for NGC4013, a galaxy in which vertically extended dust has already been detected in optical images, we can detect vertically extended dust, and the derived scaleheight agrees with the value estimated through radiative transfer modelling. Our analysis hints at a correlation between the dust scaleheight and its degree of clumpiness, which we infer from the difference between the dust masses as calculated from modelling of optical data and from fitting the spectral energy distribution of Herschel datapoints. [ABSTRACT FROM AUTHOR]

When combined with infrared observations with the Spitzer telescope (3 to 160 μm), the Herschel Space Observatory now fully samples the thermal dust emission up to 500 μm and enables us to better estimate the total infrared-submm energy budget (LTIR) of nearby galaxies. We present new empirical calibrations to estimate resolved and integrated total infrared luminosities from Spitzer and Herschel bands used as monochromatic or combined tracers. We base our calibrations on resolved elements of nearby galaxies (3 to 30 Mpc) observed with Herschel. We perform a resolved spectral energy distribution (SED) modelling of these objects using the Draine & Li dust models and investigate the influence of the addition of Spectral and Photometric Imaging Receiver (SPIRE) measurements in the estimation of LTIR. We find that using data up to 250 μm leads to local LTIR values consistent with those obtained with a complete coverage (up to 500 μm) within ±10 per cent for most of our resolved elements. We then study the distribution of energy in the resolved SEDs of our galaxies. The bulk of energy (30–50 per cent) is contained in the [70–160 μm] band. The [24–70 μm] fraction decreases with increasing metallicity. The [160–1100 μm]submillimetre band can account for up to 25 per cent of the LTIR in metal-rich galaxies. We investigate the correlation between the total infrared (TIR) surface brightnesses/luminosities and monochromatic Spitzer and Herschel surface brightnesses/luminosities. The three Photodetector Array Camera and Spectrometer (PACS) bands can be used as reliable monochromatic estimators of the LTIR, the 100 μm band being the most reliable monochromatic tracer. There is also a strong correlation between the SPIRE 250 μm and LTIR, although with more scatter than for the PACS relations. We also study the ability of our monochromatic relations to reproduce integrated LTIR of nearby galaxies as well as LTIR of z ∼ 1–3 sources. Finally, we provide calibration coefficients that can be used to derive TIR surface brightnesses/luminosities from a combination of Spitzer and Herschel surface brightnesses/fluxes and analyse the associated uncertainties. [ABSTRACT FROM AUTHOR]

We use the near-infrared Brγ hydrogen recombination line as a reference star formation rate (SFR) indicator to test the validity and establish the calibration of the Herschel/PACS 70μm emission as a SFR tracer for sub-galactic regions in external galaxies. Brγ offers the double advantage of directly tracing ionizing photons and of being relatively insensitive to the effects of dust attenuation. For our first experiment, we use archival Canada-France-Hawaii Telescope Brγ and Ks images of two nearby galaxies: NGC 5055 and NGC 6946, which are also part of the Herschel program KINGFISH (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel). We use the extinction corrected Brγ emission to derive the SFR(70) calibration for Hii regions in these two galaxies. A comparison of the SFR(70) calibrations at different spatial scales, from 200 pc to the size of the whole galaxy, reveals that about 50% of the total 70μm emission is due to dust heated by stellar populations that are unrelated to the current star formation.We use a simple model to qualitatively relate the increase of the SFR(70) calibration coefficient with decreasing region size to the star formation timescale. We provide a calibration for an unbiased SFR indicator that combines the observed Hα with the 70μm emission, also for use in Hii regions. We briefly analyze the PACS 100 and 160μm maps and find that longer wavelengths are not as good SFR indicators as 70μm, in agreement with previous results.We find that the calibrations show about 50% difference between the two galaxies, possibly due to effects of inclination. [ABSTRACT FROM AUTHOR]

We present Herschel/SPIRE images at 250, 350, and 500 μm of NGC 4244, a typical low-mass, disk-only and edge-on spiral galaxy. The dust disk is clumpy and shows signs of truncation at the break radius of the stellar disk. This disk coincides with the densest part of the Hi disk. We compare the spectral energy distribution (SED), including the new SPIRE fluxes, to 3D radiative transfer models; a smooth model disk and a clumpy model with embedded heating. Each model requires a very high value for the dust scale-length (hd = 2-5 h"), higher dust masses than previous models of NGC 4244 (Md = 0.47-1.39 ×107 M☉) and a face-on optical depth of τf.o.V = 0.4-1.12, in agreement with previous disk opacity studies. The vertical scales of stars and dust are similar. The clumpy model much better mimics the general morphology in the sub-mm images and the general SED. The inferred gas-to-dust mass ratio is compatible with those of similar low-mass disks. The relatively large radial scale-length of the dust disk points to radial mixing of the dusty ISM within the stellar disk. The large vertical dust scale and the clumpy dust distribution of our SED model are both consistent with a scenario in which the vertical structure of the ISM is dictated by the balance of turbulence and self-gravity. [ABSTRACT FROM AUTHOR]

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 µm emission shows evidence for a submillimeter excess. In addition, the traction of dust heating attributed to intense radiation fields associated with photodissociation regions is found to be (21 ± 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. [ABSTRACT FROM AUTHOR]

In 2007, R Coronae Borealis (R CrB) went into a historically deep and long decline. In this state, the dust acts like a natural coronagraph at visible wavelengths, allowing faint nebulosity around the star to be seen. Imaging has been obtained from 0.5 to 500 µm with Gemini/GMOS, Hubble Space Telescope/WFPC2, Spitzer/MIPS, and Herschel/SPIRE. Several of the structures around R CrB are cometary globules caused by wind from the star streaming past dense blobs. The estimated dust mass of the knots is consistent with their being responsible for the R CrB declines if they form along the line of sight to the star. In addition, there is a large diffuse shell extending up to 4 pc away from the star containing cool 25 K dust that is detected all the way out to 500 µm. The spectral energy distribution of R CrB can be well fitted by a 150 AU disk surrounded by a very large diffuse envelope which corresponds to the size of the observed nebulosity. The total masses of the disk and envelope are 10-4 and 2 M⊙, respectively, assuming a gas-to-dust ratio of 100. The evidence pointing toward a white dwarf merger or a final-helium-shell flash origin for R CrB is contradictory. The shell and the cometary knots are consistent with a fossil planetary nebula. Along with the fact that R CrB shows significant lithium in its atmosphere, this supports the final-helium-shell flash. However, the relatively high inferred mass of R CrB and its high fluorine abundance support a white dwarf merger. [ABSTRACT FROM AUTHOR]

Gamma-ray burst (GRB) host galaxies have been studied extensively in optical photometry and spectroscopy. Here we present the first mid-infrared spectrum of a GRB host, HG 031203. It is one of the nearest GRB hosts at z = 0.1055, allowing both low- and high-resolution spectroscopy with the Spitzer Infrared Spectrograph (IRS). Medium-resolution UV to K-band spectroscopy with the X-shooter spectrograph on the Very Large Telescope is also presented, along with Spitzer IRAC and MIPS photometry, as well as radio and submillimeter observations. These data allow us to construct a UV to radio spectral energy distribution with almost complete spectroscopic coverage from 0.3 to 35 µm of a GRB host galaxy for the first time, potentially valuable as a template for future model comparisons. The IRS spectra show strong, high-ionization fine structure line emission indicative of a hard radiation field in the galaxy--in particular the [S IV]/[S III] and [Ne III]/[Ne II] ratios--suggestive of strong ongoing star formation and a very young stellar population. The absence of any polycyclic aromatic hydrocarbon emission supports these conclusions, as does the probable hot peak dust temperature, making HG 031203 similar to the prototypical blue compact dwarf galaxy (BCD), II Zw 40. The selection of HG 031203 via the presence of a GRB suggests that it might be a useful analog of very young star-forming galaxies in the early universe, and hints that local BCDs may be used as more reliable analogs of star formation in the early universe than typical local starbursts. We look at the current debate on the ages of the dominant stellar populations in z ~ 7 and z ~ 8 galaxies in this context. The nebular line emission is so strong in HG 031203 that at z ~ 7, it can reproduce the spectral energy distributions of z-band dropout galaxies with elevated IRAC 3.6 and 4.5 µm fluxes without the need to invoke a 4000 Å break. Indeed, photometry of HG 031203 shows elevation of the broadband V-magnitude at a level similar to the IRAC elevation in stacked z-band dropouts, solely due to its strong [O III] line emission. [ABSTRACT FROM AUTHOR]

It is both surprising and exciting to find that young galaxies at high redshift contain large dust masses. For galaxies at z > 5, after only 1 Gyr, there has not been time for low-mass stars to have evolved to the AGB phase and produce dust. In such galaxies, Type II SNe and red supergiants (RSGs) may even dominate the dust production rate. It has long been known that RSG atmospheres produce dust, but little is known about it. We are pursuing three parallel studies to better understand RSG dust. First, we are using optical spectra and JHK photometry to characterize the optical and near-IR extinction curves of the RSGs. Second, we are using the optical spectra combined with 2MASS, IRAC and MIPS photometry to estimate the dust mass loss rates from Local Group RSGs. In addition, we will use our Monte Carlo radiative transfer models to analyze the emission from dust in the circumstellar shells. Third, the final piece of the puzzle is being provided by obtaining new IRS spectra of LMC and SMC RSGs. We plan to use the IRS to make a systematic study of the dust properties in RSG shells in the LMC and SMC so that we can probe how they may vary with a large range of galactic metallicities. The derived stellar SEDs and extinction curves will be combined with Spitzer IRAC and MIPS photometry and IRS spectra for use as inputs to our Monte Carlo codes which will be used to study the composition, size distributions and clumpiness of the dust. [ABSTRACT FROM PUBLISHER]

We investigate which conditions of dust attenuation and stellar populations allow models of dusty, continuously star-forming, bulge-less disc galaxies at to meet the different colour selection criteria of high- z‘red’ galaxies (e.g. ). As a main novelty, we use stellar population models that include the thermally pulsating asymptotic giant branch (TP-AGB) phase of stellar evolution. The star formation rate of the models declines exponentially as a function of time, the e-folding time being longer than 3 Gyr. In addition, we use calculations of radiative transfer of the stellar and scattered radiation through different dusty interstellar media in order to explore the wide parameter space of dust attenuation. We find that synthetic discs can exhibit red optical/near-infrared colours because of reddening by dust, but only if they have been forming stars for at least ∼1 Gyr. Extremely few models barely exhibit , if the inclination and if the opacity . Hence, -selected galaxies at most probably are either systems with an old, passively evolving bulge or starbursts. Synthetic discs at exhibit , if they are seen edge on (i.e. at ) and if . This explains the large fraction of observed, edge-on disc-like galaxies with and . Finally, models with exhibit , with no bias towards and for a large range in opacity (e.g. for ). In conclusion, red disc-like galaxies at may not necessarily be dustier than nearby disc galaxies (with ) and/or much older than ∼1 Gyr. This result is due both to a realistic description of dust attenuation and to the emission contribution by TP-AGB stars, with ages of 0.2 to 1–2 Gyr and intrinsically red colours. [ABSTRACT FROM AUTHOR]

This in vitro study evaluated the performance of an ulnar head replacement. A joint simulator was employed that produced active forearm rotation in cadaveric specimens, with motion measured using an electromagnetic tracking system. The kinematics of the intact forearm were compared with a partial ulnar head replacement and a full replacement (with and without soft-tissue reconstruction) and a full excision of the ulnar head. There were no differences between intact kinematics and those following prosthetic reconstruction. However, ulnar head excision produced distal radioulnar joint instability in the form of radioulnar convergence and increased anteroposterior translations. [ABSTRACT FROM PUBLISHER]

Analysis of dental microwear on chimpanzee molars reveals much variation that reflects jaw mechanics and occlusal function rather than diet. Observed microwear pattern differences relate to variations in molar position, facet type, and overall age of the tooth. Gradients in the amounts of shear and compression generated at different points in the molar series relative to the condyle probably account for pattern variations associated with molar position, while differences in facet inclination may affect the vectors of compression and shear, resulting in facet differences. Age-related pattern differences may be a result of surface and subsurface variations in enamel hardness. These results demonstrate that intraspecific and intra-individual differences in microwear may be extreme, and care must be taken to distinguish normal variation due to occlusal mechanics from variations due to dietary difference. The finding that microwear variations are reflective of subtle changes in occlusal forces and vectors along the tooth row might in itself be a clinically useful phenomenon. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 26-year-old man with a 6-year history of swelling and pain of his scrotum and penis. He was diagnosed with Crohn's disease (CD) associated with anogenital granulomatosis (AGG) and orofacial granulomatosis (OFG). The pathology of AGG and OFG is described. Cutaneaous features of CD and the distinction of CD and AGG are discussed.

A 21-year-old man presented to genitourinary (GU) medicine physicians with (initially) painful penile and scrotal swelling. A diagnosis of ano-genital granulomatosis was confirmed on histological analysis of penile skin. Enquiring about systemic symptoms resulted in the additional diagnosis of gastrointestinal Crohn's disease. The patient is now receiving immunosuppressive therapy to treat both conditions. [ABSTRACT FROM AUTHOR]

We characterize the dust in NGC 628 and NGC 6946, two nearby spiral galaxies in the KINGFISH sample. With data from 3.6 μm to 500 μm, dust models are strongly constrained. Using the Draine & Li dust model (amorphous silicate and carbonaceous grains), for each pixel in each galaxy we estimate (1) dust mass surface density, (2) dust mass fraction contributed by polycyclic aromatic hydrocarbons, (3) distribution of starlight intensities heating the dust, (4) total infrared (IR) luminosity emitted by the dust, and (5) IR luminosity originating in regions with high starlight intensity. We obtain maps for the dust properties, which trace the spiral structure of the galaxies. The dust models successfully reproduce the observed global and resolved spectral energy distributions (SEDs). The overall dust/H mass ratio is estimated to be 0.0082 ± 0.0017 for NGC 628, and 0.0063 ± 0.0009 for NGC 6946, consistent with what is expected for galaxies of near-solar metallicity. Our derived dust masses are larger (by up to a factor of three) than estimates based on single-temperature modified blackbody fits. We show that the SED fits are significantly improved if the starlight intensity distribution includes a (single intensity) “delta function” component. We find no evidence for significant masses of cold dust (T ≲ 12 K). Discrepancies between PACS and MIPS photometry in both low and high surface brightness areas result in large uncertainties when the modeling is done at PACS resolutions, in which case SPIRE, MIPS70, and MIPS160 data cannot be used. We recommend against attempting to model dust at the angular resolution of PACS. [ABSTRACT FROM AUTHOR]

We present an analysis of the dust and gas in Andromeda, using Herschel images sampling the entire far-infrared peak. We fit a modified-blackbody model to ∼4000 quasi-independent pixels with spatial resolution of ∼140 pc and find that a variable dust-emissivity index (β) is required to fit the data. We find no significant long-wavelength excess above this model, suggesting there is no cold dust component. We show that the gas-to-dust ratio varies radially, increasing from ∼20 in the center to ∼70 in the star-forming ring at 10 kpc, consistent with the metallicity gradient. In the 10 kpc ring the average β is ∼1.9, in good agreement with values determined for the Milky Way (MW). However, in contrast to the MW, we find significant radial variations in β, which increases from 1.9 at 10 kpc to ∼2.5 at a radius of 3.1 kpc and then decreases to 1.7 in the center. The dust temperature is fairly constant in the 10 kpc ring (ranging from 17 to 20 K), but increases strongly in the bulge to ∼30 K. Within 3.1 kpc we find the dust temperature is highly correlated with the 3.6 μm flux, suggesting the general stellar population in the bulge is the dominant source of dust heating there. At larger radii, there is a weak correlation between the star formation rate and dust temperature. We find no evidence for “dark gas” in M31 in contrast to recent results for the MW. Finally, we obtained an estimate of the CO X-factor by minimizing the dispersion in the gas-to-dust ratio, obtaining a value of (1.9 ± 0.4) × 1020 cm–2 [K km s–1]–1. [ABSTRACT FROM AUTHOR]

We estimate the total dust input from the cool evolved stars in the Small Magellanic Cloud, using the 8 μm excess emission as a proxy for the dust-production rate (DPR). We find that asymptotic giant branch (AGB) and red supergiant (RSG) stars produce (8.6-9.5) × 10–7M☼ yr–1 of dust, depending on the fraction of far-infrared sources that belong to the evolved star population (with 10%-50% uncertainty in individual DPRs). RSGs contribute the least (<4%), while carbon-rich AGB stars (especially the so-called extreme AGB stars) account for 87%-89% of the total dust input from cool evolved stars. We also estimate the dust input from hot stars and supernovae (SNe), and find that if SNe produce 10–3M☼ of dust each, then the total SN dust input and AGB input are roughly equivalent. We consider several scenarios of SN dust production and destruction and find that the interstellar medium (ISM) dust can be accounted for solely by stellar sources if all SNe produce dust in the quantities seen around the dustiest examples and if most SNe explode in dense regions where much of the ISM dust is shielded from the shocks. We find that AGB stars contribute only 2.1% of the ISM dust. Without a net positive contribution from SNe to the dust budget, this suggests that dust must grow in the ISM or be formed by another unknown mechanism. [ABSTRACT FROM AUTHOR]