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Exhumation of plutonic systems is driven by a range of mechanisms including isostatic, tectonic, and erosional processes. Variable rates of plutonic exhumation in active subduction systems may be driven by idiosyncrasies of regional geology or by first‐order tectonic features. We report new age, isotope, and low‐temperature thermochronology constraints of granitoids from the Hida Mountains of central Japan that constrain the highest rates and magnitude of plutonic rock exhumation within the Japan and one of the highest worldwide. This extreme exhumation is centered on the apex of a lithospheric scale anticlinorium associated with the subduction of the Izu‐Bonin oceanic arc. The spatial and temporal relationship between the exhumation of these Pleistocene plutons and the subducting/accreting Izu‐Bonin oceanic arc links the plate‐scale geodynamics and regional exhumation patterns. Identifying thermochronological anomalies within magmatic arcs provides an opportunity to identify ancient asperities previously subducted and responsible for rapid exhumation rates within ancient subduction systems. Plutonic rocks reach the surface through a variety of geological processes. Generally, this is driven by active tectonic and erosive forces. We provide high‐precision geochronological constraint on the youngest exposed subduction zone plutons found in the Hida Mountains of Japan that are 818.5 ± 9.6 thousand years old. Regionally, the Hida Mountains is identified as a thermochronological “hot spot” where the rocks in the region came to the surface very rapidly within the past ~300,000 years. The exhumation of these plutons was driven by the subduction of the Izu‐Bonin oceanic arc. Timing of crystallization and exhumation of the youngest exposed plutons is constrained with high precision analytical techniquesOne of the highest exhumation rates for plutonic rocks worldwide is reportedExhumation of Pleistocene granitoid plutons is driven by subducting Izu‐Bonin oceanic arc

The Tumblagooda Sandstone in Western Australia documents Early Paleozoic rifting in East Gondwana and provides the earliest evidence for terrestrial activity of multicellular animals on Earth. We constrain the provenance of this sequence using 737 concordant U–Pb ages of detrital zircons from two stratigraphic wells in the northern Perth Basin and Southern Carnarvon Basin and outcrops of the type sections near Kalbarri. Detrital zircon age signatures are linked to infrared spectral data and stratigraphic logs. These ages span 3,312–466 Ma, including major Precambrian age peaks at 1,079–1,544 Ma, 1,695–2,403 Ma, and 2,640–2,879 Ma, consistent with igneous sources in the West Australian Craton. Significant Early Paleozoic age peaks at 499–541 Ma suggest a North Indian Orogen source. The maximum depositional age is constrained by the youngest detrital zircon, which yields an age of 466 ± 8 Ma. Our age constraints imply that terrestrial activity of multicellular animals on Earth may not be older than Middle Ordovician (Darriwilian). Rifting resulted in the exposure of the Yilgarn Craton and the segmentation of the Pinjarra Orogen. The Northampton Complex segment of the Pinjarra Orogen constituted a basement high that separated subbasins during the onset of rifting. Discordant Archean zircons provide a consistent record of radiogenic Pb loss at ~470 Ma, which we interpret as being related to the denudation of the Yilgarn Craton. The Pb loss event suggests that intracratonic rifting in the Pinjarra Orogen was initiated in the Middle Ordovician, after the Kuunga Orogeny completed the final amalgamation of Gondwana. Early Paleozoic rift in East Gondwana involved denudation of Proterozoic Pinjarra Orogen and Archean Yilgarn Craton basementNorthampton Complex (Pinjarra Orogen) constituted a basement high that separated subbasins during the onset of riftingDetrital zircon age spectra constrain West Australian Craton and North Indian provenance for continental red beds

Aims. Dust grains in the planet-forming regions around young stars are expected to be heavily processed due to coagulation, fragmentation, and crystallization. This paper focuses on the crystalline silicate dust grains in protoplanetary disks for a statistically significant number of TTauri stars (96).

Aims.We search for Polycyclic Aromatic Hydrocarbon (PAH) features towards young low-mass (T Tauri) stars and compare them with surveys of intermediate mass (Herbig Ae/Be) stars. The presence and strength of the PAH features are interpreted with disk radiative transfer models exploring the PAH feature dependence on the incident UV radiation, PAH abundance and disk parameters.

Detrital zircons from four samples of upper Dalradian metasedimentary rocks from the Buchan Block in the NE Grampian Highlands of Scotland were analysed by laser ablation inductively coupled plasma mass spectrometry to establish their U-Pb age and trace element composition. The analysed grains (magmatic cores) mainly yield concordant ages ranging from Neoproterozoic to Eoarchaean. Kernel density plots of the data show pronounced peaks in the late Mesoproterozoic, Palaeoproterozoic and Neoarchaean eras. The data are indistinguishable from detrital zircon age spectra from Dalradian rocks elsewhere, an interpretation supported by application of a non-parametric multidimensional scaling algorithm, and are consistent with a Laurentian source. Similar to existing studies from other Dalradian rocks, the age spectra from the Buchan Block reveal an increase in the relative proportion of older detritus with time, suggesting derivation from late Mesoproterozoic (Grenville) then Palaeoproterozoic orogens before widespread exposure and denudation of their Archaean basement rocks. Application of a novel approach to estimate the most likely time of radiogenic-Pb loss indicates that some detrital zircon grains were affected by element mobility around 470-450 Ma as a result of Grampian orogenesis. [ABSTRACT FROM AUTHOR]

ABSTRACTContagious ovine digital dermatitis (CODD) is an important foot disease in sheep, with significant animal welfare and economic implications. It is thought that CODD emerged from bovine digital dermatitis (BDD) via treponemal bacteria. With wildlife species such as elk now suffering a CODD-like disease, it is imperative to clarify these disease etiologies. A large investigation into treponemal association with CODD is warranted. CODD lesions (n= 58) and healthy sheep foot tissues (n= 56) were analyzed by PCR for the three BDD-associated Treponemaphylogroups and two other lameness-associated bacteria, Dichelobacter nodosusand Fusobacterium necrophorum. Spirochete culture was also attempted on CODD lesions. “Treponema medium/Treponema vincentii-like,” “Treponema phagedenis-like,” and Treponema pedisspirochetes were identified in 39/58 (67%), 49/58 (85%), and 41/58 (71%) of CODD lesions, respectively. One or more BDD-associated Treponemaphylogroups were detected in 100% of CODD lesions. Healthy foot tissues did not amplify BDD-associated Treponemaphylogroup DNA. D. nodosusand F. necrophorumwere present in 34/58 (59%) and 41/58 (71%) of CODD lesions and 22/56 (39%) and 5/56 (9%) of healthy foot tissues, respectively. Thirty-two spirochetes were isolated from CODD lesions, with representatives clustering with, and indistinguishable from, each of the three BDD-associated Treponemaphylogroups based on 16S rRNA gene comparisons. This study for the first time demonstrates a high-level association for BDD treponeme phylogroups in CODD and their absence from healthy tissues, supporting the hypothesis that BDD treponemes play a primary causative role in CODD and confirming that the specific PCR assays are an effective differential diagnostic tool for CODD.

ABSTRACTSince 2008, a large increase in the numbers of cases of lameness have been seen in wild North American elk (Cervus elaphus) from Washington State, USA. The most recent cases manifested as foot lesions similar both clinically and pathologically to those seen in digital dermatitis (DD) in cattle and sheep, a disease with a bacterial etiopathogenesis. To determine whether the same bacteria considered responsible for DD are associated with elk lameness, lesion samples were subjected to bacterial isolation studies and PCR assays for three phylogroups of relevant DD treponemes. The DD treponemes were isolated from lesional tissues but not from control feet or other areas of the diseased foot (including the coronary band or interdigital space), suggesting that the bacteria are strongly associated with DD lesions and may therefore be causal. In addition, PCR analysis revealed that all three unique DD treponeme phylotypes were found in elk hoof disease, and in 23% of samples, all 3 DD-associated treponemes were present in lesions. Sequence analysis of the 16S rRNA gene showed that the elk lesion treponemes were phylogenetically almost identical to those isolated from cattle and sheep DD lesions. The isolates were particularly similar to two of the three culturable DD treponeme phylotypes: specifically, the Treponema medium/Treponema vincentii-like and Treponema phagedenis-like DD spirochetes. The third treponeme culturable phylogroup (Treponema pedis), although detected by PCR, was not isolated. This is the first report describing isolation of DD treponemes from a wildlife host, suggesting that the disease may be evolving to include a wider spectrum of cloven-hoofed animals.

The Spitzer Space Telescope allows for the .rst time to search systematically for very low luminosity (≲0.1 L⊙) objects (VeLLOs) associated with dense molecular cores. They may be the .rst candidate Class 0 sources with sub-stellar masses. We describe such a source in the dense molecular core L1148. VeLLO natal cores show properties that are unusual for star-forming cores. The low luminosity and in some cases the lack of prominent out.ow could be the result of the small gas supply near the VeLLO. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Summary Future research directions for agricultural geography were the subject of debate in Area in the late 1980s, and the subsequent application of political economy ideas undoubtedly revived interest in agricultural research. This paper argues that agricultural geography contains greater diversity than the dominant political economy discourse would suggest. It reviews ‘other’ areas of agricultural research such as policy, post‐ productivism, people, culture and animals, presenting future suggestions which should ensure that agricultural research continues revitalized rather than redundant into the next millennium.

L. flavus and L. pseudoflavus can be distinguished and separated by the differences in the patterning of the external body coloration. The light coloration was expressed as small speckles in L. flavus causing the animals to have a dusky appearance and in L. pseudoflavus of blotches causing a mottled appearance. The two species overlapped in the range of coloration although L. pseudoflavus from Ireland tended to be darker and greener than L. flavus. In L. flavus the juvenile keel stripe persisted longer than in L. pseudoflavus and could persist, in some animals, until they were a third to a half, grown. Coloration could be affected by keeping animals in the laboratory: L. pseudoflavus originating from material collected from Ireland became much darker than the original material, with a wider range of mottling. Despite the two species having much greater similarity in external appearance than originally reported, there was no overlap in the diagnostic characters of the distal genitalia.

We investigate the vacuum alignment in a fully dynamical “moose” model which breaks electroweak symmetry with a top quark condensate and show how the prefered vacuum depends on the explicit masses of the fermions involved. Our results are also applicable to the cases in which electroweak symmetry is broken by a fourth family of quarks, or by a technicolour mechanism. Such moose models allow the scale of new physics, ?, to be in the TeV range with the absence of flavour changing neutral currents ensured by a GIM mechanism.

Spectroscopy was obtained for several infrared sources embedded in molecular clouds. The spectrometer used a cooled grating and was flown on the Kuiper Airborne Observatory. Spectra were obtained for portions of the features at 6.0 and 6.8 microns, which are seen in absorption against infrared sources lying deep in molecular clouds. The present observations were obtained with a resolution of 0.008 micron, and confirm the continuous nature of the absorption, thus supporting a dust-grain origin. A search for residual structure in the absorption features on a scale of 0.01 to 0.10 micron revealed none in the 6.0 micron feature. Structure on a scale of 0.05 micron may be present in the 6.8 micron feature. Suggested identifications of the materials responsible for these features are discussed.

Observations of the moon and HD 44179 were obtained in the wavelength range of 7.5-8.5 microns at a resolving power of approximately 800. The spectrum of the moon shows absorptions caused by telluric methane. Use of the moon as a calibrator is effective in removing these atmospheric lines. The spectrum of HD 44179 shows that the 7.7-micron emission feature does not break up into discrete, resolved emission features. Instead, it must be a broad, apparently continuous, emission feature.

ABSTRACTSpirochetes of the genus Treponemawere cultured from 7 of 10 cases of digital dermatitis in sheep. Two cultures comprised Treponema phagedenis-like and Treponema medium/Treponema vincentii-like spirochetes, respectively, while the remaining cultures comprised mixed populations of Treponema medium/Treponema vincentii-like, Treponema phagedenis-like, and Treponema denticola/Treponema putidum-like organisms.

Bovine digital dermatitis (BDD), an infectious disease of the bovine foot with a predominant treponemal etiology, is a leading cause of lameness in dairy and beef herds worldwide. BDD is poorly responsive to antimicrobial therapy and exhibits a relapsing clinical course; an effective vaccine is therefore urgently sought. Using a reverse vaccinology approach, the present study surveyed the genomes of the three BDD-associated Treponemaphylogroups for putative ß-barrel outer membrane proteins and considered their potential as vaccine candidates.

We have modelled chemical abundances and line profiles in the Bok globule B335. The chemical characteristics of this star-forming core are largely determined by gas-grain interaction in the inflowing material. By comparing high resolution observational data with our model it should be possible to determine the evolutionary status of B335 and to establish the role that surface chemistry plays in protostellar clouds.

Both contagious ovine digital dermatitis (CODD) and bovine digital dermatitis (BDD) are causes of infectious lameness in sheep and cattle, respectively, and are strongly associated with the presence of specific treponemes, with three different cultivable phylogroups commonly isolated: Treponema medium, Treponema phagedenisand Treponema pedis. The aim of this study was to investigate the potential to transmit CODD‐associated Treponemaspecies via gloves used when handling visibly clinically affected animals. The feet of sheep with and without CODD were handled as part of routine examination with gloved hands. The gloves were then swabbed to detect the presence of treponemes immediately after handling. Detection methods included culture and isolation techniques together with DNA detection by PCR. In addition, the duration of survival in air was determined as well as the efficacy of common disinfectants to remove treponemes from gloves. In this study, we demonstrate that CODD‐associated treponemes can survive on gloves used to handle the feet of CODD‐affected sheep but may be removed effectively using common disinfectants. These data provide evidence of a potential route of transmission and identify a practical method to reduce this risk.

A search has been made for the 110← 111transition of thioformaldehyde in interstellar clouds where formaldehyde is known to exist. Failure to detect this transition indicates that the ratio of thioformaldehyde abundance to that of formaldehyde is probably less than the abundance ratio of sulfur to oxygen.

Context.Forsterite is one of the crystalline dust species that is often observed in protoplanetary disks and solar system comets. Being absent in the interstellar medium, it must be produced during the disk lifetime. It can therefore serve as a tracer of dust processing and disk evolution, which can lead to a better understanding of the physical processes occurring in the disk, and possibly planet formation. However, the connection of these processes with the overall disk crystallinity remains unclear.

Context. A survey of mid-infrared gas-phase emission lines of H2, H2O and various atoms toward a sample of 43 embedded low-mass young stars in nearby star-forming regions is presented. The sources are selected from the Spitzer“Cores to Disks” (c2d) legacy program. Aims. The environment of embedded protostars is complex both in its physical structure (envelopes, outflows, jets, protostellar disks) and the physical processes (accretion, irradiation by UV and/or X-rays, excitation through slow and fast shocks) which take place. The mid-IR spectral range hosts a suite of diagnostic lines which can distinguish them. A key point is to spatially resolve the emission in the Spitzer-IRS spectra to separate extended PDR and shock emission from compact source emission associated with the circumstellar disk and jets.Methods. An optimal extraction method is used to separate both spatially unresolved (compact, up to a few hundred AU) and spatially resolved (extended, thousand AU or more) emission from the IRS spectra. The results are compared with the c2d disk sample and literature PDR and shock models to address the physical nature of the sources.Results. Both compact and extended emission features are observed. Warm ($T_\mathrm{ex}$few hundred K) H2, observed through the pure rotational H2S(0), S(1) and S(2) lines, and [S i] 25 μm emission is observed primarily in the extended component. [S i] is observed uniquely toward truly embedded sources and not toward disks. On the other hand hot ($T_\mathrm{ex}$$\ga$700 K) H2, observed primarily through the S(4) line, and [Ne ii] emission is seen mostly in the spatially unresolved component. [Fe ii] and [Si ii] lines are observed in both spatial components. Hot H2O emission is found in the spatially unresolved component of some sources.Conclusions. The observed emission on ≥1000 AU scales is characteristic of PDR emission and likely originates in the outflow cavities in the remnant envelope created by the stellar wind and jets from the embedded young stars. Weak shocks along the outflow wall can also contribute. The compact emission is likely of mixed origin, comprised of optically thick circumstellar disk and/or jet/outflow emission from the protostellar object.

Aims. We aim to study the composition and energetics of the circumstellar material of DK Cha, an intermediate-mass star in transition from an embedded configuration to a star plus disk stage, during this pivotal stage of its evolution.Methods. Using the range scan mode of PACS on the HerschelSpace Observatory, we obtained a spectrum of DK Cha from 55 to 210 μm as part of the DIGIT key program.Results. Almost 50 molecular and atomic lines were detected, many more than the 7 lines detected in ISO-LWS. Nearly the entire ladder of CO from J= 14–13 to 38–37 (Eu/k= 4080 K), water from levels as excited as $J_{K_{-1}K_{+1}}$= 707(Eu/k= 843 K), and OH lines up to Eu/k= 290 K were detected.Conclusions. The continuum emission in our PACS SED scan matches the flux expected by a model consisting of a star, a surrounding disk of 0.03 $M_\odot$, and an envelope of a similar mass, supporting the suggestion that the object is emerging from its main accretion stage. Molecular, atomic, and ionic emission lines in the far-infrared reveal the outflow's influence on the envelope. The inferred hot gas may be photon-heated, but some emission may be caused by C-shocks in the walls of the outflow cavity.

Context. We present far-infrared spectroscopic observations, taken with the Photodetector Array Camera and Spectrometer (PACS) on the HerschelSpace Observatory, of the protoplanetary disk around the pre-main-sequence star HD 100546. These observations are the first within the DIGIT Herschelkey program, which aims to follow the evolution of dust, ice, and gas from young stellar objects still embedded in their parental molecular cloud core, through the final pre-main-sequence phases when the circumstellar disks are dissipated.Aims. Our aim is to improve the constraints on temperature and chemical composition of the crystalline olivines in the disk of HD 100546 and to give an inventory of the gas lines present in its far-infrared spectrum. Methods. The 69 μm feature is analyzed in terms of position and shape to derive the dust temperature and composition. Furthermore, we detected 32 emission lines from five gaseous species and measured their line fluxes. Results. The 69 μm emission comes either from dust grains with ~70 K at radii larger than 50 AU, as suggested by blackbody fitting, or it arises from ~200 K dust at ~13 AU, close to the midplane, as supported by radiative transfer models. We also conclude that the forsterite crystals have few defects and contain at most a few percent iron by mass. Forbidden line emission from [C ii] at 157 μm and [O i] at 63 and 145 μm, most likely due to photodissociation by stellar photons, is detected. Furthermore, five H2O and several OH lines are detected. We also found high-J rotational transition lines of CO, with rotational temperatures of ~300 K for the transitions up to J= 22–21 and T~ 800 K for higher transitions.

Background: Low systemic blood flow as measured by superior vena cava (SVC) flow is common in very preterm infants. It is strongly associated with IVH and disability and may be caused by poor cardiac adaptation to high vascular resistance (VR)[1]. Because of limited efficacy of therapeutic circulatory support using traditional inotropes[2], we are exploring a preventative approach using Milrinone, an inodilator that increases contractility and reduces VR. The aim of this study was to examine the safety and pharmaco-kinetics (PK) of Milrinone infusion given prophylactically from 3 hours to very preterm infants (median GA 26w) at risk of low blood flow.Methods: A dose escalation and PK study was undertaken, starting with low dose infusion (0.25mcg/kg/min) followed by a higher dose (0.5mcg/kg/min) from 3 until 24 hours of age. Monitoring was with serial echocardiography and head ultrasound (HUS). Serial blood Milrinone levels were taken for PK analysis. Using this data, a population modelling and simulation approach established an optimal dosing profile that fulfilled our preventative aim and achieved target drug levels. This regimen was to load with 0.75mcg/kg/min for 3 hours and maintain with 0.2mcg/kg/min until 18 hours of age. The primary outcome was maintenance of SVC flow >45ml/kg/min in the absence of severe hypotension. Secondary outcomes included intraventricular haemorrhage (IVH). Exit criteria: BP >24mmHg for over 30 mins unresponsive to inotropes.Results: At both infusion rates in the dose escalation phase of study, target blood levels were not achieved quickly enough, only 64% of babies maintained SVC flow and Milrinone levels were high by 24 hrs. Ten infants were then studied using the optimised regimen. All maintained SVC flow >45 ml/kg/min (compared to 40% in an historical cohort) and had drug concentrations within the target therapeutic range. No infant met exit criteria. No immediate adverse effects attributable to Milrinone were noted. There were 3 late deaths attributable to severe respiratory failure and NEC and one from late diagnosis of lethal congenital malformation.Conclusion: Population PK modelling in the preterm infant has been able to establish an optimal dose regimen for Milrinone that fulfils preventative aims. These encouraging results are currently being investigated for therapeutic efficacy within a pilot RCT.