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We describe the ocular features and normal physiological parameters of the South Island takahe (Porphyrio hochstetteri), using three birds. Both eyes face slightly forward such that there is some a...

The illustration is an important tool to aid in the description and understanding of anatomy, and penguins (Aves: Sphenisciformes: Spheniscidae) are an important clade in environmental monitoring, paleontology, and other research fields. Traditionally, anatomic illustration has been informed by dissection. More recently, micro-computed tomography (micro-CT) has proven to be a powerful tool for three-dimensional anatomic imaging, although larger specimens are more challenging to image due to increased X-ray attenuation. Here, we used traditional dissection and micro-CT to illustrate the skulls of Aptenodytes patagonicus, Eudyptula minor, and Pygoscelis papua, and the extracranial soft tissue of E. minor. Micro-CT prevented the loss of orientation, disarticulation, and distortion of bones that might result from cleaning and drying skulls, while immobilization was achieved by freezing the specimens before imaging. All bony elements in the head were accurately depicted. Fixing, dehydrating, and diffusion staining with iodine (diceCT) enabled the identification of muscles and other large nonmineralized structures, but specimen preparation precluded the ability to show smaller nerves and vessels. The results presented here provide a guide for anatomic studies of penguins and our summary of sample preparation and imaging techniques are applicable for studies of other similarly sized biological specimens.

Chip-scale optical frequency combs can provide broadband spectroscopy for diagnosing complex organic molecules. They are also promising as miniaturized laser spectrometers in applications ranging from atmospheric chemistry to geological science and the search for extraterrestrial life. While optical cavities are commonly used to boost sensitivity, it is challenging to realize a compact cavity-enhanced comb-based spectrometer. Here, we apply the Vernier technique to free-running operation of an interband cascade laser frequency comb in a simple linear geometry that performs cavity-enhanced chemical sensing. A centimeter-scale high-finesse cavity simultaneously provides selective mode filtering and enhancement of the path length to 30 meters. As a proof-of-concept, we sense transient open-path releases of ppm-level difluoroethane with 2 ms temporal resolution over a 1 THz optical bandwidth centered at 3.64 $\mu$m., Comment: 10 pages, 5 figures

Interband cascade lasers are convenient sources for generating optical frequency combs that cover 1 THz within the 3-6 µm region. We apply these monolithic devices towards trace gas detection with enhancement cavities using Vernier spectroscopy.

CDHR3 (cadherin-related family member 3) is a transmembrane protein that is highly expressed in airway epithelia and the only known receptor for rhinovirus C (RV-C). A CDHR3 SNP (rs6967330) with G to A base change has been linked to severe exacerbations of asthma and increased susceptibility to RV-C infections in young children. The goals of this study were to determine the subcellular localization of CDHR3 and to test the hypothesis that CDHR3 asthma-risk genotype affects epithelial cell function and susceptibility to RV-C infections of the airway epithelia. We used immunofluorescence imaging, Western blot analysis, and transmission electron microscopy to show CDHR3 subcellular localization in apical cells, including expression in the cilia of airway epithelia. Polymorphisms in CDHR3 rs6967330 locus (G→A) that were previously associated with childhood asthma were related to differences in CDHR3 expression and epithelial cell function. The rs6967330 A allele was associated with higher overall protein expression and RV-C binding and replication compared with the rs6967330 G allele. Furthermore, the rs6967330 A allele was associated with earlier ciliogenesis and higher FOXJ1 expression. Finally, CDHR3 genotype had no significant effects on membrane integrity or ciliary beat function. These findings provide information on the subcellular localization and possible functions of CDHR3 in the airways and link CDHR3 asthma-risk genotype to increased RV-C binding and replication.

SUMMARYAirway epithelium is the first body surface to contact inhaled irritants and report danger. We studied how epithelial cells recognize and respond to protease, which is a critical component of many allergens that provoke asthma. In a murine model, the aeroallergen alkaline protease 1 (Alp1) of Aspergillus sp. elicited helper T (Th) cell-dependent lung eosinophilia. Bronchiolar club cells responded rapidly to Alp1 by coordinating the accumulation of allergic immune cells in the lung. Alp1 degraded bronchiolar cell junctions, and club cells within the bronchioles propagated this signal via calcium and calcineurin to incite inflammation. In two human cohorts, we linked fungal sensitization and asthma with SNP/protein expression of the mechanosensitive calcium channel, TRPV4. TRPV4 was also necessary and sufficient for club cells to sensitize mice to Alp1. Thus, club cells detect junction damage as mechanical stress, which signals danger via TRPV4, calcium and calcineurin to initiate Th cell sensitization.Graphical Abstract

High circulating IL-6 may define a phenotype of asthma associated with obesity and systemic inflammation. We demonstrate that circulating IL-6 is higher in African-American patients with asthma, and that race-specific thresholds should be considered.

Orthobiologics such as autologous conditioned serum (ACS) are often used to treat joint disease in horses. Because ACS is generated from the horse's own blood, any medication administered at the time of preparation would likely be present in stored ACS, which could lead to an inadvertent positive drug test following intra-articular (IA) injection. The main objective of this study was to determine if ACS prepared from firocoxib positive horses could result in detectable plasma concentrations of the drug following IA injection. Firocoxib was administered to six horses at 0.1mg/kg PO twice at a 24h interval. Blood was obtained at 4h following the second dose and transferred to a separate syringe (Arthrex IRAP II) for ACS preparation. Plasma and ACS concentrations of firocoxib were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). When horses were confirmed firocoxib negative, 7.5mL of ACS was injected into both tarsocrural joints. Blood samples were collected at 0, 4, 8, 12, 24, and 48h, and firocoxib concentration was measured. Mean (±standard error of the mean, SEM) plasma concentration of firocoxib 4h following the second dose was 33.3±4.72ng/mL. Mean (±SEM) firocoxib concentration in ACS was 35.4±4.47ng/mL. Fourteen days following the second and last dose of firocoxib, mean plasma concentration was below the lower limit of detection (LOD=1ng/mL) in all horses. Following IA injection of ACS, plasma concentrations of firocoxib remained below LOD at all times in all horses. ACS generated from horses with therapeutic plasma concentrations of firocoxib did not contain sufficient firocoxib to lead to a positive plasma drug test following IA administration.

Order-of-accuracy verification is necessary to ensure that software correctly solves a given set of equations. One method for verifying the order of accuracy of a code is the method of manufactured solutions. This study documents the development of a manufactured solution that allows verification of not only the Euler, Navier-Stokes, and Reynolds-averaged Navier-Stokes equation sets, but also some of their associated boundary conditions: slip, no-slip (adiabatic and isothermal), and outflow (subsonic, supersonic, and mixed). To demonstrate the usefulness of this manufactured solution, it has been used for order-of-accuracy verification in a compressible computational fluid dynamics code. All of the results shown are on skewed, nonuniform, three-dimensional meshes. The manufactured solution and sequence of meshes are designed to allow asymptotic results to be obtained with reasonable computational cost. In addition to the order of accuracy of the full code for various equation sets and boundary conditions, the order of accuracy of code portions used to calculate solution gradients has been measured as well.

The governing equations for the radiation-diffusion approximation to radiative transport are a system of highly nonlinear, multiple time-scale, partial-differential equations. The numerical solution of these equations for very large-scale simulations is most often carried out using semi-implicit linearization or operator-splitting techniques. These techniques do not fully converge the nonlinearities of the system so as to reduce the cost and complexity of the transient solution at each time step. For a given time-step size, this process exchanges temporal accuracy for computational efficiency. This study considers the temporal-accuracy issue by presenting detailed numerical-convergence studies for problems related to radiation-diffusion simulations. In this context a particular spatial discretization based on a Galerkin finite-element technique is used. The time-integration methods that we consider include: fully implicit, semi-implicit, and operator-splitting techniques. Results are presented for the relative accuracy and the asymptotic order of accuracy of the various methods. The results demonstrate both first-order and second-order asymptotic order of accuracy for the fully implicit, semi-implicit, and the operator-splitting schemes. Additionally a second-order operatorsplitting linearized-diffusion method is also presented.

The method of manufactured solutions is used to verify the order of accuracy of two finite-volume Euler and Navier–Stokes codes. The Premo code employs a node-centred approach using unstructured meshes, while the Wind code employs a similar scheme on structured meshes. Both codes use Roe's upwind method with MUSCL extrapolation for the convective terms and central differences for the diffusion terms, thus yielding a numerical scheme that is formally second-order accurate. The method of manufactured solutions is employed to generate exact solutions to the governing Euler and Navier–Stokes equations in two dimensions along with additional source terms. These exact solutions are then used to accurately evaluate the discretization error in the numerical solutions. Through global discretization error analyses, the spatial order of accuracy is observed to be second order for both codes, thus giving a high degree of confidence that the two codes are free from coding mistakes in the options exercised. Examples of coding mistakes discovered using the method are also given. Copyright © 2004 John Wiley & Sons, Ltd.

The electronic properties of the trimeric oxo-centred [Fe 3 OL 3 ] complex (L is a doubly negatively charged pentadentate ligand, providing five nitrogens for iron coordination) have been investigated by Mossbauer spectroscopy, magnetic susceptibility and a theoretical treatment including the phenomena of double-exchange interaction. Two quadrupole doublets I and II with the ratio ∼2:1 are observed at 4.2 K. By comparing the isomer shifts of these doublets ( δ I =0.52 mm s −1 and δ II =0.99 mm s −1 ) with those of other mixed metal complexes with comparable iron–ligand coordination it is concluded in this study that [Fe 3 OL 3 ] exhibits a partially delocalised ground state: Fe 2.9+ Fe 2.9+ Fe 2.2+ . At elevated temperatures the Mossbauer spectra of [Fe 3 OL 3 ] exhibit two additional doublets III and IV ( δ III =0.60 mm s −1 and δ IV =0.80 mm s −1 at 20 K), which are ascribed to an additional partially delocalised state, i.e. Fe 2.75+ Fe 2.75+ Fe 2.5+ . By admitting the coexistence of two types of clusters with different delocalised valence states, it is possible to consistently fit the Mossbauer spectra over the whole temperature range (4.2–332 K) being investigated. Temperature-dependent magnetic susceptibility data of [Fe 3 OL 3 ] from 2 to 295 K can be analysed by the Heisenberg–Dirac–Van Vleck model with only two exchange parameters J =−140 cm −1 and J 1 =−49 cm −1 , describing the Fe(III)Fe(III) and Fe(III)Fe(II) exchange interactions and yielding a net antiferromagnetic coupling of the three paramagnetic sites with a spin-triplet ground state. In order to explain the seemingly contradictory situation that the Mossbauer spectra of [Fe 3 OL 3 ] exhibit partial valence delocalisation while it is possible to analyse the magnetic data with valence-trapped ground state and exited states a theoretical treatment is presented, which includes antiferromagnetic exchange, double exchange and vibronic interactions.

Frequency‐domain shot‐record migration can produce higher quality images than Kirchhoff migration but typically at a greater cost. The computing cost of shot‐record migration is the product of the number of shots in the survey and the expense of each individual migration. Many attempts to reduce this cost have focused on the speed of the individual migrations, trying to achieve a better trade‐off between accuracy and speed. Another approach is to reduce the number of migrations. We investigate the simultaneous migration of shot records using frequency‐domain shot‐record migration algorithms. The difficulty with this approach is the production of so‐called crossterms between unrelated shot and receiver wavefields, which generate unwanted artifacts or noise in the final image. To reduce these artifacts and obtain an image comparable in quality to the single‐shot‐per‐migration result, we have introduced a process called phase encoding, which shifts or disperses these crossterms. The process of phase encoding thus allows one to trade S/N ratio for the speed of migrating the entire survey. Several encoding functions and two application strategies have been tested. The first strategy, combining multiple shots per migration and using each shot only once, reduces computation in direct relation to the number of shots combined. The second strategy, performing multiple migrations of all the shots in the survey, provides a means to reduce the crossterm noise by stacking the resulting images. The additional noise in both strategies may be tolerated if it is no stronger than the inherent seismic noise in the migrated image and if the final image is achieved with less cost.

Mossbauer studies were performed on single crystals of guanidinium nitroprusside with different orientations of their principal crystallographic axes (a, b, c) with respect to the incident radiation. The markedly anisotropic Lamb-Mossbauer factor f LM , i.e. f LM (a) = 0.118(8), f LM (b) = 0.174(8), f LM (c) = 0.202(8) is in contrast to that of nitroprussides with inorganic anions. The observed anisotropy is ascribed to the anisotropic vibrational mean-square displacement of the nitroprusside anions as a whole which is due to the specific packing of both, anions and cations, as well as the very weak chemical bonding between the ions, typical only for guanidinium nitroprusside. The vibrational anisotropy of iron atoms in barium nitroprusside that has been observed by X-ray structural investigations has a different origin and therefore does not result in an anisotropic Lamb-Mossbauer factor. We have also investigated metastable states in guanidinium nitroprusside that have been populated by means of incoherent irradiation from light-emitting diodes. With a specific orientation of the guanidinium nitroprusside single crystal a population of the metastable states up to 26% could be achieved. Populations of comparable size on lithium, sodium and potassium nitroprussides have only been reached using coherent laser irradiation.

We have developed a flexible Discontinuous Galerkin (DG) toolkit for full-wave inversion (FWI) that operates on unstructured non-affine meshes using a variety of element types (quadrilateral, triangular, hexahedral). The code handles spatially-variable polynomial-order across the mesh, and includes two approaches: modal DG with exact adjoints and gradients, and spectral DG which, though computationally faster, has approximate adjoints and gradients. In this paper, we show that high-quality full wave inversion results are obtained using both the modal DG and the approximate spectral DG approaches. A 3D inversion of field data using spectral-element DG will be presented in the talk.

We have studied the recombination kinetics of carboxymyoglobin (after photodissociation of the CO ligand) by Mossbauer spectroscopy for temperatures in the range 4.2 – 60 K. The observed kinetics display non-exponential behaviour which was monitored over periods of a few days. It is shown that the time dependence of the kinetics can be reduced to a single universal function of the temperature-dependent variable (t/τ1/2(T)) β(T) . The half-decay time τ1/2(T) and the scaling parameter β(T) are analysed for the presence of tunneling effects. The non-Arrhenius temperature dependence of the half-decay time below 60 K is interpreted as activated tunneling in models with an Eckart barrier or a fluctuating barrier.