Cobalt and chromium exposure affects osteoblast function and impairs the mineralization of prosthesis surfaces in vitro.

Cobalt (Co) and chromium (Cr) ions and nanoparticles equivalent to those released through tribo-corrosion of prosthetic metal-on-metal (MOM) bearings and taper junctions are detrimental to osteoblast activity and function in-vitro when examined as individual species. Here we examined the effects of Co(2+) :Cr(3+) and Co(2+) :Cr(6+) combinations on osteoblast-like SaOS-2 cellular activity, alkaline phosphatase (ALP) activity and mineralization to better reflect clinical exposure conditions in vivo. We also assessed the effect of Co(2+) :Cr(3+) combinations and Co:Cr nanoparticles on SaOS-2 cell osteogenic responses on grit-blasted, plasma-sprayed titanium-coated and hydroxyapatite-coated prosthesis surfaces. Cellular activity and ALP activity were reduced to a greater extent with combination treatments compared to individual ions. Co(2+) and Cr(3+) interacted additively and synergistically to reduce cellular activity and ALP activity respectively, whilst the Co(2+) with Cr(6+) combination was dominated by the effect of Cr(6+) alone. Mineralization by osteoblasts was greater on hydroxyapatite-coated surfaces compared to grit-blasted and plasma-sprayed titanium-coated surfaces. Treatments with Co(2+) :Cr(3+) ions and Co:Cr nanoparticles reduced the percentage mineralization on all surfaces, with hydroxyapatite-coated surfaces having the least reduction. In conclusion, our data suggests that previous studies investigating individual metal ions underestimate their potential clinical effects on osteoblast activity. Furthermore, the data suggests that hydroxyapatite-coated surfaces may modulate osteoblast responses to metal debris. This article is protected by copyright. All rights reserved

Price Prediction in a Trading Agent Competition

The 2002 Trading Agent Competition (TAC) presented a challenging market game in the domain of travel shopping. One of the pivotal issues in this domain is uncertainty about hotel prices, which have a significant influence on the relative cost of alternative trip schedules. Thus, virtually all participants employ some method for predicting hotel prices. We survey approaches employed in the tournament, finding that agents apply an interesting diversity of techniques, taking into account differing sources of evidence bearing on prices. Based on data provided by entrants on their agents' actual predictions in the TAC-02 finals and semifinals, we analyze the relative efficacy of these approaches. The results show that taking into account game-specific information about flight prices is a major distinguishing factor. Machine learning methods effectively induce the relationship between flight and hotel prices from game data, and a purely analytical approach based on competitive equilibrium analysis achieves equal accuracy with no historical data. Employing a new measure of prediction quality, we relate absolute accuracy to bottom-line performance in the game

Classification of Multiwavelength Transients with Machine Learning

With the advent of powerful telescopes such as the Square Kilometer Array and the Vera C. Rubin Observatory, we are entering an era of multiwavelength transient astronomy that will lead to a dramatic increase in data volume. Machine learning techniques are well suited to address this data challenge and rapidly classify newly detected transients. We present a multiwavelength classification algorithm consisting of three steps: (1) interpolation and augmentation of the data using Gaussian processes; (2) feature extraction using wavelets; and (3) classification with random forests. Augmentation provides improved performance at test time by balancing the classes and adding diversity into the training set. In the first application of machine learning to the classification of real radio transient data, we apply our technique to the Green Bank Interferometer and other radio light curves. We find we are able to accurately classify most of the 11 classes of radio variables and transients after just eight hours of observations, achieving an overall test accuracy of 78 percent. We fully investigate the impact of the small sample size of 82 publicly available light curves and use data augmentation techniques to mitigate the effect. We also show that on a significantly larger simulated representative training set that the algorithm achieves an overall accuracy of 97 percent, illustrating that the method is likely to provide excellent performance on future surveys. Finally, we demonstrate the effectiveness of simultaneous multiwavelength observations by showing how incorporating just one optical data point into the analysis improves the accuracy of the worst performing class by 19 percent.Comment: 16 pages, 12 figure

Automatic Optic Nerve Measurement: A New Tool to Standardize Optic Nerve Assessment in Ultrasound B-Mode Images

Transorbital sonography provides reliable information about the estimation of intra-cranial pressure by measuring the optic nerve sheath diameter (ONSD), whereas the optic nerve (ON) diameter (OND) may reveal ON atrophy in patients with multiple sclerosis. Here, an AUTomatic Optic Nerve MeAsurement (AUTONoMA) system for OND and ONSD assessment in ultrasound B-mode images based on deformable models is presented. The automated measurements were compared with manual ones obtained by two operators, with no significant differences. AUTONoMA correctly segmented the ON and its sheath in 71 out of 75 images. The mean error compared with the expert operator was 0.06 ± 0.52 mm and 0.06 ± 0.35 mm for the ONSD and OND, respectively. The agreement between operators and AUTONoMA was good and a positive correlation was found between the readers and the algorithm with errors comparable with the inter-operator variability. The AUTONoMA system may allow for standardization of OND and ONSD measurements, reducing manual evaluation variability

Destruction of the Mott Insulating Ground State of Ca_2RuO_4 by a Structural Transition

We report a first-order phase transition at T_M=357 K in single crystal Ca_2RuO_4, an isomorph to the superconductor Sr_2RuO_4. The discontinuous decrease in electrical resistivity signals the near destruction of the Mott insulating phase and is triggered by a structural transition from the low temperature orthorhombic to a high temperature tetragonal phase. The magnetic susceptibility, which is temperature dependent but not Curie-like decreases abruptly at TM and becomes less temperature dependent. Unlike most insulator to metal transitions, the system is not magnetically ordered in either phase, though the Mott insulator phase is antiferromagnetic below T_N=110 K.Comment: Accepted for publication in Phys. Rev. B (Rapid Communications

Quality Function Deployment and operational design decisions – A healthcare infrastructure development case study

The purpose of this paper is to demonstrate how Quality Function Deployment (QFD) can enhance a healthcare organisation’s strategic operational alignment, by synchronising the infrastructure design with the service intention. In this empirical paper, a case study of a £15 million infrastructure development has been used as the unique context to assess and test the experimental findings. QFD was utilised in order to capture and transform the requirements of decision-makers, providers, patients and local communities’ into both service and building design for Project K, a healthcare infrastructure, in the UK. QFD was implemented after the public consultation. The large amount of qualitative data collected from the public consultation was analysed using thematic analysis, which was used as the main QFD inputs. A series of eight facilitated workshops enabled a cross-functional team of 10 high-ranking managers to optimise the future infrastructure features. Two full iterations of the QFD results are presented. Using QFD generated effectiveness and efficiency by creating an information exchange platform and providing the stakeholders with a framework to optimise the decision-making. This paper makes a practical contribution by empirically testing the QFD modelling and providing evidence of its implementation within the complex, dynamic and evolving nature of the healthcare built environment sector. Moreover, from an academic perspective, this study makes a contribution by responding to the call inviting scholars to grow and advance the embryonic and undeveloped research of QFD application in the construction industry (Cudney and Gillis, 2016; Dikmen et al., 2005 and John et al., 2014)

Rms-flux relation of Cyg X-1 with RXTE: dipping and nondipping cases

The rms (root mean square) variability is the parameter for understanding the emission temporal properties of X-ray binaries (XRBs) and active galactic nuclei (AGN). The rms-flux relation with Rossi X-ray Timing Explorer (RXTE) data for the dips and nondip of black hole Cyg X-1 has been investigated in this paper. Our results show that there exist the linear rms-flux relations in the frequency range 0.1-10 Hz for the dipping light curve. Moreover, this linear relation still remains during the nondip regime, but with the steeper slope than that of the dipping case in the low energy band. For the high energy band, the slopes of the dipping and nondipping cases are hardly constant within errors. The explanations of the results have been made by means of the ``Propagating Perturbation'' model of Lyubarskii (1997).Comment: 15 pages, 12 figures, Accepted for publication in Astrophysics & Space Scienc

Maritime Navigation: Characterizing Collaboration in a High-Speed Craft Navigation Activity

acceptedVersio

The Turkey Ig-like receptor family: identification, expression and function.

The chicken leukocyte receptor complex located on microchromosome 31 encodes the chicken Ig-like receptors (CHIR), a vastly expanded gene family which can be further divided into three subgroups: activating CHIR-A, bifunctional CHIR-AB and inhibitory CHIR-B. Here, we investigated the presence of CHIR homologues in other bird species. The available genome databases of turkey, duck and zebra finch were screened with different strategies including BLAST searches employing various CHIR sequences, and keyword searches. We could not identify CHIR homologues in the distantly related zebra finch and duck, however, several partial and complete sequences of CHIR homologues were identified on chromosome 3 of the turkey genome. They were designated as turkey Ig-like receptors (TILR). Using cDNA derived from turkey blood and spleen RNA, six full length TILR could be amplified and further divided according to the typical sequence features into one activating TILR-A, one inhibitory TILR-B and four bifunctional TILR-AB. Since the TILR-AB sequences all displayed the critical residues shown to be involved in binding to IgY, we next confirmed the IgY binding using a soluble TILR-AB1-huIg fusion protein. This fusion protein reacted with IgY derived from various gallinaceous birds, but not with IgY from other bird species. Finally, we tested various mab directed against CHIR for their crossreactivity with either turkey or duck leukocytes. Whereas no staining was detectable with duck cells, the CHIR-AB1 specific mab 8D12 and the CHIR-A2 specific mab 13E2 both reacted with a leukocyte subpopulation that was further identified as thrombocytes by double immunofluorescence employing B-cell, T-cell and thrombocyte specific reagents. In summary, although the turkey harbors similar LRC genes as the chicken, their distribution seems to be distinct with predominance on thrombocytes rather than lymphocytes