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The Bishop Tuff (BT), erupted from the Long Valley caldera in California, displays two types of geochemical gradients with temperature: one is related to magma mixing, whereas the other is found in the high-SiO2 rhyolite portion of the Bishop Tuff and is characterized by twofold or lower concentration variations in minor and trace elements that are strongly correlated with temperature. It is proposed that the latter zonation, which preceded phenocryst growth, developed as a result of mineral–melt partitioning between interstitial melt and surrounding crystals in a parental mush, from which variable melt fractions were segregated. To test this hypothesis, trends of increasing vs decreasing element concentrations with temperature (as a proxy for melt fraction), obtained from published data on single-clast pumice samples from the high-SiO2 rhyolite portion of the Bishop Tuff, were used to infer their relative degrees of incompatibility vs compatibility between crystals and melt in the parental mush. Relative compatibility values (RCV i) for all elements i , defined as the concentration slope with temperature divided by average concentration, are shown to be linearly correlated with their respective bulk partition coefficients (bulk Di). Mineral–melt partition coefficients from the literature were used to constrain the average stoichiometry of the crystallization/melting reaction in the parental mush: 32 % quartz + 34 % plagioclase + 31 % K-feldspar + 1·60 % biotite + 0·42 % titanomagnetite + 0·34 % ilmenite + 0·093 % allanite + 0·024 % zircon + 0·025 % apatite = 100 % liquid. The proportions of tectosilicates in the reaction (i.e. location of eutectic) are consistent with depths of melt segregation of ~400–550 MPa and an activity of H2O of ~0·4–0·6. Temperatures of <770–780 °C are constrained by allanite in the reaction. Evidence that a fluid phase was present in the parental mush is seen in the decreasing versus increasing H2O and CO2 contents with temperature in the segregated interstitial melt that formed the high-SiO2 rhyolite portion of the Bishop Tuff. The presence of an excess fluid phase, which strongly partitions CO2 relative to the melt, is required to explain the compatible behavior of CO2, whereas the fluid abundance must have been low to explain the incompatible behavior of H2O. Calculated degassing paths for interstitial melts, which segregated from the parental mush and ascended to shallower depths to grow phenocrysts, match published volatile analyses in quartz-hosted melt inclusions and constrain fluid abundances in the mush to be ≤1 wt%. The source of volatiles in the parental mush, irrespective of whether it formed by crystallization or partial melting, must have been primarily from associated basalts, as granitoid crust is too volatile poor. Approximately twice as much basalt as rhyolite is needed to provide the requisite volatiles. The determination of bulk Di for several elements gives the bulk composition of the parental leucogranitic mush and shows that it is distinct from Mesozoic Sierran arc granitoids, as expected. Collectively, the results from this study provide new constraints for models of the complex, multi-stage processes throughout the Plio-Quaternary, involving both mantle-derived basalt and pre-existing crust, that led to the origin of the parental body to the Bishop Tuff. [ABSTRACT FROM AUTHOR]

Santiago Germplasm silver bluestem (Bothriochloa laguroides (DC.) Herter ssp. torreyana (Steud.) Allred & Gould [Poaceae]) was cooperatively released in 2017 as a Texas Selected Native Plant Germplasm. This germplasm is a blend of 3 native populations of B. laguroides selected through evaluation of 31 populations of silver bluestem and 21 populations of cane bluestem (Bothriochloa barbinodis (Lag.) Herter) originating from 2 ecoregions in West Texas: Southern Desertic Basins, Plains and Mountains and Western Edwards Plateau. To meet management needs within the area of intended use (West Texas), the accessions included in the release were selected based on proof of acceptable seed fill and germination, and on observations of greater survival, plant vigor, seed production, and biomass production in comparison with other native accessions, other silver bluestem germplasm releases, and a commercially available selection. Ocular estimated variables for selected accessions were 43 to 66% higher than non-selected accessions when averaged across 2 sites and 2 y. Plant height for selected accessions was 14% taller and canopy cover was 7% higher than non-selected accessions. Seed germination was 48% greater for the selected accessions. Release of Santiago Germplasm silver bluestem will provide an ecotypic seed source of a widespread native grass for use in West Texas. It provides the first ecotypic seed source of B. laguroides for use in the Western Edwards Plateau; the Southern Desertic Basins, Plains and Mountains; the Southern High Plains; and the Central Rolling Red Prairies ecoregions of Texas. [ABSTRACT FROM AUTHOR]

Cemented Thompson's prostheses have been used to treat elderly patients with displaced intracapsular hip fractures at our two units for the last 15 years, amid growing support for the use of newer implant designs for hip hemiarthroplasty. This provided us with an opportunity to investigate survival of the Thompson's stem in our patients. A retrospective cohort study was set up to review previously collected data on patients who underwent Thompson's hemiarthroplasty over a 7-year period. These were linked to surgical notes, clinical letters and radiographs to record post-operative course and subsequent admissions and procedures. The identifiers were then linked to mortality data from the Office of 'National Statistics. Kaplan-Meier survival analyses were done for implants and patients. A total of 1,632 patients (mean age 82.7 years) underwent 1,670 procedures. Five-year implant survival was 95.4 %. A total of 36 stems were revised, including 14 revisions to total hip arthroplasty and 22 excision arthroplasties. Reasons for revision included infection (2.1 %), dislocation (1.1 %) and aseptic loosening (0.5 %). Symptomatic aseptic loosening and acetabular erosion occurred late (mean time 3.2 and 5.7 years, respectively following surgery). Aseptic loosening and erosion following hemiarthroplasty are relatively late complications. [ABSTRACT FROM AUTHOR]

The eLogbook is used to collect and collate the operative experience of every orthopaedic trainee in the UK and Ireland. We describe the project and discuss the national data now emerging on elective and trauma training. [ABSTRACT FROM AUTHOR]

This paper assesses damage to diving sites off Hurghada and Safaga, Egypt, and examines management responses and options. Data were obtained using the line-intercept-transect method. Using general field observations, a control site comparison and a historical comparison, it was found that the four diving sites studied suffered varying degrees of physical damage and needed management attention. Some transect locations had experienced severe physical damage while others had escaped damage. The most obvious difference between the control site and the four damaged sites (at both 4 and 8 m depths) was the consistently high percentage cover of hard coral (especially Acropora coral) and low percentage cover of soft corals among all transects at the Giftun Canal control site. Total algae percentages were also consistently higher at impacted transect sites versus the control site. From a historical perspective, at the Small Giftun site from 1987 to 1996, percentage hard coral cover decreased by 43% and algal cover increased over fourfold. If the diving tourism industry is to sustain itself in the Egyptian Red Sea, every management effort must be made to minimise controllable sources of stress on the coral reef system. Dive site management programme options, based on peer-reviewed carrying capacity research and stakeholder involvement, are reviewed. [ABSTRACT FROM AUTHOR]

This paper presents a framework for incorporating knowledge sources directly in the space-time beamformer of airborne adaptive radars. The algorithm derivation follows the usual linearly-constrained minimum-variance (LCMV) space-time beamformer with additional constraints based on a model of the clutter covariance matrix that is computed using available knowledge about the operating environment. This technique has the desirable property of reducing sample support requirements by "blending" the information contained in the observed radar data and the a priori knowledge sources. Applications of the technique to both full degree of freedom (DoF) and reduced DoF beamformer algorithms are considered. The performance of the knowledge-aided beamforming techniques are demonstrated using high-fidelity simulated X-band radar data. [ABSTRACT FROM AUTHOR]

A compact wide tuning range design of a CMOS voltage-controlled oscillator (VCO) at W-band frequencies is presented. The design employs a differential Colpitts configuration, using a bufferless transformer output and nested inductors. The gate bias is used for frequency tuning that achieves a wide range of 93.7-100.7 GHz. A peak output power of 4.7 dBm with power efficiency of 5.5% is achieved at 98.8 GHz and the phase noise is around -80 dBc/Hz at 1 MHz offset across the tuning range. The VCO uses a silicon area of 0.15 mm2 including pads and, depending on bias, consumes between 6-63 mW of DC power. [ABSTRACT FROM AUTHOR]

The role of the surgeon is constantly evolving. He or she must adapt to the demands of this increasingly competitive profession and, in doing so, must keep abreast of the changes to the infrastructure of the NHS. One area in which there is currently significant restructuring is finance. In this article we intend to give a brief overview of this financial restructuring and the implications for the surgeon. [ABSTRACT FROM AUTHOR]

Numerous analyses of multiple ilmenite, titanomagnetite, sanidine, plagioclase, biotite, orthopyroxene, and clinopyroxene crystals (when present) in each of 24 single-clast pumices from the Bishop Tuff (BT), CA are presented, together with whole-rock compositions on the same single clasts. Data from multiple Fe–Ti oxide grains in each sample, coupled with an assessment of analytical uncertainty, show that there is a single population of ilmenite and titanomagnetite in each of 20 samples and no more than two populations of ilmenite and/or titanomagnetite in the remaining four. A statistical evaluation of microprobe uncertainty (for beam conditions of 15 kV and 10 nA) constrains the minimum number of ilmenite (≥ 21) and titanomagnetite (≥ 56) analyses required to obtain Fe–Ti two-oxide temperatures with propagated uncertainties ≤ ± 10 °C. Thermometry results confirm a continuous range (~ 700–800 °C) across the BT deposit. Plagioclase displays a bimodal compositional pattern, where a predominantly sodic (An14–15) vs. calcic (An22–23) population is found in single clasts where pyroxene is absent vs. present; the latter coincides with geochemical evidence for mixing between high-SiO2 rhyolite and less differentiated melts as previously documented in the literature. When sanidine rims are paired with plagioclase, calculated two-feldspar temperatures (~ 690–780 °C) are strongly correlated (R2 = 0.94) with Fe–Ti two-oxide temperatures. Application of plagioclase–liquid hygrometry reveals a systematic decrease in melt water content (~ 7.2–4.1 wt%) with increasing temperature across the BT deposit, consistent with experiments from the literature that show cotectic crystallization of quartz–sanidine–plagioclase in rhyolite melt requires a concomitant decrease of ~ 3 wt% H2O between 700 and 800 °C at 200 MPa. Single-clast, whole-rock concentrations of some elements (e.g., Rb) correlate strongly with Fe–Ti oxide temperature (R2 = 0.95). The Mg# in biotite also correlates strongly with temperature (R2 = 0.97), as do the Mg# values in orthopyroxene and clinopyroxene with whole-rock Mg# (R2 = 0.6 and 0.8, respectively) and melt water content (R2 = 0.7 for both). Evidence points to biotite crystallization in all BT samples from high-SiO2 rhyolite melt, which was already continuously zoned in composition and temperature prior to mixing with less differentiated melts, as previously noted in the literature. In contrast, several lines of evidence, including hydrous phase-equilibrium experiments on rhyolites from the literature, show that both pyroxenes in BT pumices co-crystallized with calcic plagioclase (~ An21–29), in equilibrium with both titanomagnetite and ilmenite, after mixing between less differentiated melt(s) and relatively hot (≥ 755 °C) high-SiO2 rhyolite. [ABSTRACT FROM AUTHOR]

Presents evidence that indicates that both major histocompatibility complex (MHC)-linked transporter genes, (Ham-1 and Ham-2) are probably required for class I antigen processing, and that the functional transporter in this pathway may consist ofa Ham-1/Ham-2 heterodimer. Conclusion that the Ham-2 gene completely restores the ability of RMA-S (a mutant murine cell line) to process and present antigen to class-I-restricted T-cells.

Determines the cause of the low levels of insulin-like growth factor (IGF-I) and bone mineral density (BMD) in adults with untreated coeliac disease. Increase in mean BMD; Improvements in mucosal aberrations following a one year gluten-free diet; Impact of zinc deficiency in the production of IGF-I.

Background: In the United Kingdom, organizations involved in health-care commissioning have recently introduced legislation limiting access to total knee arthroplasty through the introduction of arbitrary thresholds unsupported by the literature and based on body mass index. This study aimed to establish the relationship between body mass index and patient-reported specific and general outcomes on total knee arthroplasty.Methods: Using national patient-reported outcome measures (PROMs) linked to the National Joint Registry, we identified 13,673 primary total knee arthroplasties performed for the treatment of osteoarthritis. The PROMs project involves the collection of condition-specific and general health outcomes before and at six months following total knee arthroplasty. The relationships between body mass index and the Oxford Knee Score, EuroQol 5D index, and EuroQol 5D Visual Analogue Scale were assessed with use of scatterplots and linear regression. The improvement in these measures was compared for three distinct groups based on body mass index (Group I [15 to 24.9 kg/m(2)], Group II [25 to 39.9 kg/m(2)], and Group III [40 to 60 kg/m(2)]) with use of multiple regression analysis to adjust for differences in age, sex, American Society of Anesthesiologists grade, general health rating, and number of comorbidities.Results: The preoperative and postoperative patient-reported outcome measures declined to a similar extent with increasing body mass index. The gradient of the linear regression equation relating to the change in scores was positive in all cases, indicating that there was a tendency for scores to improve to a greater extent as body mass index increased. After adjustment, the changes in patient-reported outcome measures in Group I and Group III were equivalent for the Oxford Knee Score (mean difference, 0.5 point [95% confidence interval, -0.5 to 1.5 points]; p = 0.78), the EuroQol 5D index (mean difference, 0.014 point [95% confidence interval, -0.021 to 0.048 point]; p = 1.00), and the EuroQol 5D Visual Analogue Scale (mean difference, 1.9 points [95% confidence interval, -0.4 to 4.1 points]; p = 0.13). Wound complications were significantly higher (p < 0.001) at a rate of 17% (168 of 1018 patients) in Group III compared with 9% (121 of 1292 patients) in Group I.Conclusions: The improvements in patient-reported outcome measures experienced by patients were similar, irrespective of body mass index. Health policy should be based on the overall improvements in function and general health gained through surgery. Obese patients should not be excluded from the benefit of total knee arthroplasty, given that their overall improvements were equivalent to those of patients with a lower body mass index. [ABSTRACT FROM AUTHOR]

The eLogbook is used to collect and collate the operative experience of every orthopaedic trainee in the UK and Ireland. We describe the project and discuss the national data now emerging on elective and trauma training. [ABSTRACT FROM AUTHOR]