Bovine coronary region keratinocyte colony formation is supported by epidermal-dermal interactions

Delineating the factors that orchestrate keratinocyte growth and differentiation in the claw is pivotal to understanding the quality of hoof horn production in health and disease. The specific objectives of this in- vestigation were to establish an in vitro culture system for bovine coronary region keratinocytes and dermal fibroblasts, determine the colony-forming capacity of epidermal keratinocytes in the coronary region, and characterize transcriptional changes in specific cy- tokine, growth factor, and receptor genes during colony formation in coculture. Fibroblasts and keratinocytes from the coronary region of the lateral, hind limb claw were collected, and 5.0 × 103 and 7.5 × 103 kerati- nocytes were cultured in the presence or absence of fibroblast monolayers, respectively. The 2 densities of keratinocytes formed 144 ± 15.8 and 183 ± 26.9 colo- nies, respectively, in the presence of dermal fibroblasts, whereas no colonies developed in the absence of dermal fibroblasts. Keratinocytes with the ability to show colony formation comprised 1.09% ± 0.16 to 1.77% ± 0.28 of the keratinocyte population isolated from the coronary region. Keratinocyte–fibroblast cocultures developed a time-dependent increased expression of several growth factors, cytokines, and receptors. These findings demonstrated that keratinocytes from the bo- vine coronary region formed colonies in vitro and that colony formation occurred with an absolute dependence on dermal fibroblasts. Colony growth was associated with increased transcriptional expression of cytokine, growth factor, and receptor expression known to drive keratinocyte colony formation in other species. The re- sults indicate that horn-producing keratinocytes must interact with dermal fibroblasts during normal tissue homeostasis in the bovine claw

Age, segment, and horn disease affect expression of cytokines, growth factors, and receptors in the epidermis and dermis of the bovine claw

The aim of this study was to examine changes in RNA expression for growth factors, cytokines, and receptors in epidermal-dermal tissues of the bovine claw relative to hostage, claw segment, and disease state of the horn. Epidermal-dermal tissues were collected from the coronary, wall, sole, and bulb segments of 8- to 9-mo-old Holstein fetuses, normal adult cows, and adult cows with sole ulceration. Anatomic and pathologic characteristics were determined in tissues stained with eosin and hematoxylin, and RNA expression levels were evaluated using real-time, quantitative PCR. In normal tissues, certain RNA expression levels were clearly affected by hostage: 290.0-, 610.0-, 53.4-, and 8.1-fold greater expression of granulocyte-macrophage colony-stimulating factor was observed in fetal coronary, wall, sole, and bulb segment relative to adult tissues, respectively. A claw segment effect was also observed in that IL-1α expression was greater (1.59-fold) in the normal adult wall relative to the coronary segment, and IL- 18 expression was greater (16.2-fold) in the normal adult sole compared with the coronary segment and 2.88 greater in the fetal sole relative to the bulb segment. Sole ulceration was associated with hemorrhage, thrombosis, inflammation, and striking increases in IL-1β, IL-18, and inducible nitric oxide synthase, and with less dramatic, albeit measurable, changes in IL-1 type I receptor, IL-1 receptor antagonist, and tumor necrosis factor-α. Amidst striking increases in keratinocyte growth factor receptor (i.e., 21.0-fold, 10.4-fold, 0, and 21.6-fold in the coronary, wall, sole, and bulb segments, respectively), a concomitant decrease occurred in keratinocyte growth factor (i.e., 0.80-, 0.54-, 0.56-, and 0.72-fold, respectively). The results demonstrated changes in disease state and, to a lesser extent, claw segment and were accompanied by alterations in the RNA expression of several cytokines, growth factors, and receptors present in the normal claw

Zircon U-Pb geochronology of the Mount Givens Granodiorite: Implications for the genesis of large volumes of eruptible magma

The Mount Givens Granodiorite, a large pluton in the central Sierra Nevada batholith, California, is similar in area to zoned intrusive suites yet is comparatively chemically and texturally homogenous. New zircon U-Pb geochronology indicates that the pluton was constructed over at least 7 Ma from 97.92 ± 0.06 Ma to 90.87 ± 0.05 Ma. Combining the new geochronology with the exposed volume of the pluton yields an estimated magma flux of <0.001 km3/a. The geochronologic data are at odds with the previously speculated links between plutons such as the Mount Givens Granodiorite and large-volume homogeneous ignimbrites (often termed monotonous intermediates). Existing data indicate that large plutons accumulate at rates of ≤0.001 km3/a, 1-2 orders of magnitude less than fluxes calculated for dated monotonous intermediates. If monotonous intermediates are remobilized, erupted plutons accumulated at rates comparable to dated examples, they should preserve a record of zircon growth of up to 10 Ma. Alternatively, the long history of zircon growth recorded in plutons may be erased during the processes of reheating and remobilization that precede supervolcano eruption. However, zircon dissolution modeling, based on hypothetical temperature-time histories for preeruptive monotonous intermediates, indicates that rejuvenation events would not sufficiently dissolve zircon. We suggest that eruptions of monotonous intermediates occur during high magmatic flux events, leaving little behind in the intrusive rock record, whereas low fluxes favor pluton accumulation

The pace of plutonism

Beneath volcanoes are magmas that never erupt but that become frozen into feldspar- and quartz-rich rocks broadly called granite. Where the crystallized magmas form bodies with distinctive textures, they are grouped into named units-plutons. The rate (pace) at which magmas accumulate into plutons is fundamental to understanding both how room is made for the magmas and how unerupted and erupted magmas are connected. Dating plutonic rocks suggests that plutons accumulate slowly. Although the pace of magma accumulation does not preclude direct connections between plutons and small volcanic eruptions, it appears to be far too slow to support connections between most plutons and supereruptions

The plutonic record of a silicic ignimbrite from the Latir volcanic field, New Mexico

Zircon U-Pb geochronologic data for plutonic rocks in the Latir volcanic field, New Mexico, demonstrate that the rocks are dominated by plutons that post-date ignimbrite eruption. Only zircon from the ring dike of the Questa caldera yields the same age (25.64±0.08 Ma) as zircon from the caldera-forming Amalia Tuff (25.52±0.06 Ma). The post-caldera Rio Hondo pluton was assembled incrementally over at least 400 ka. The magma accumulation rate for the exposed portion of the Rio Hondo pluton is estimated to be 0.0003 km3 a-1, comparable to rates for other plutons, and too slow to support accumulation of large eruptible magma volumes. Extrapolation of the accumulation rate for the Rio Hondo pluton over the history of the Latir volcanic field yields an estimated volume of plutonic rocks comparable to the calculated volume under the field as determined by geophysical studies. We propose that the bulk of the plutonic rocks beneath the volcanic center accumulated during periods of low volcanic effusivity. Furthermore, because the oldest portion of the Rio Hondo pluton is the granitic cap exposed beneath a gently dipping roof contact, the roof granite cannot be a silicic liquid fractionated from the deeper (younger) portions of the pluton. Instead, our data suggest that the compositional heterogeneity of the Rio Hondo pluton is inherited from lower crustal sources. We suggest that if magma fluxes are high enough, zoned ignimbrites can be formed by evolution of the melt compositions generated at the source with little or no shallow crustal differentiation

On the application of population-based structural health monitoring in aerospace engineering

One of the major obstacles to the widespread uptake of data-based Structural Health Monitoring so far, has been the lack of damage-state data for the (mostly high-value) structures of interest. To address this issue, a methodology for sharing data and models between structures has been developed–Population-Based Structural Health Monitoring (PBSHM). PBSHM works on the principle that, if populations of structures are sufficiently similar, or share sections which can be considered similar, then data and models can be shared between them for use in diagnostic inference. The PBSHM methodology therefore relies on two key components: firstly, identifying whether structures are sufficiently similar for successful transfer of diagnostics; this is achieved by the use of an abstract representation of structures. Secondly, machine learning techniques are exploited to effectively transfer information between the structures in a way that improves damage detection and classification across the whole population. Although PBSHM has been conceived to deal with large and general classes of structures, much of the detailed developments presented so far have concerned bridges; the aim of this paper is to provide similarly detailed discussions in the aerospace context. The overview here will examine data transfer between aircraft components, as well as illustrating how one might construct an abstract representation of a full aircraft

Promoting socially just and inclusive music teacher education: Exploring perceptions of early-career teachers

Teacher education plays a significant role in influencing generations of future teachers. This article aims to explore the role of pre-service teacher education in promoting socially just and inclusive practices in music education. Six pre-service teachers were interviewed before graduating, and then again six months into their first year of teaching. The interviewees reflected on their understandings of what constitutes being inclusive in the music classroom and how these understandings have been influenced by their perceptions of both university and school experiences. The article provides insights into the ways that teacher education programmes might equip early-career teachers to engage in a variety of teaching practices that are socially just, within the music classroom

Risk Factors for Nipah Virus Encephalitis in Bangladesh1

Patients in Goalando were likely infected by direct contact with fruit bats or their secretions, rather than through contact with an intermediate host

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02