bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Behaviour of a Vertical Natural Circulation Two Pressure Stage HRSG Behind a Heavy Duty Gas Turbine
Authors: Stamatelopoulos Georg N. , Ponweiser Karl , Walter Heimo , Linzer Wladimir , Neßler Hubert , Strohmaier Robert
Published: August 2014

Modern combined cycle gas turbines are highly flexible in their operation, concerning start up, load change and shut down. Heat Recovery Steam Generators (HRSG) arranged downstream of the Gas Turbine (GT) are forced to operate in such a way, that the gas turbine operation is not restricted by them. Therefore, they should be designed for a high cycling capability with typical values in the range of 200 to 250 cold starts, 1000 warm and 2500 hot starts for their typical 25 year life span. Cold starts are defined as a standstill period of over 120 hours, warm starts to a weekend shutdown and hot starts to an overnight shut down.

AE Energietechnik GmbH (AE), a Babcock Borsig Power company has specialized in designing, erecting and commissioning vertical natural circulation multiple pressure stage HRSGs. The vertical design combines simplicity and low investment costs with performance reliability and high availability. In order to forecast the dynamic behaviour of such a HRSG, AE has supported the development of a dynamic simulation code at the Institute of Thermal Engineering (ITW) located at the Vienna University of Technology. This finite volume code enables the prediction of velocities, pressures and temperatures for several dynamic processes of the HRSG.

In the present paper computational results of starts and load changes will be presented for a vertical natural circulation HRSG. Furthermore, several design optimization changes which where made in order to increase operational reliability and availability will be demonstrated. Finally, practical applications of already constructed HRSG will be discussed and conclusions will be drawn.
United States Navy (USN) Integrated Power System (IPS) Testing Experience With a LM2500 Generator Set Utilizing a MicroNet Controller
Authors: Kingsley Joseph , Stauffer Matthew
Published: August 2014

The US Navy has been researching integrated electric propulsion systems for many years. The economic advantages of the integrated electric architecture, where power for propulsion as well as ship service are derived from a common set of generators, are well recognized and such systems are used throughout many sectors of the commercial marine industry today. In addition to the economic advantages, there are military benefits to the ship when an Integrated Power System (IPS) architecture is adopted. Those include increased reliability and survivability, reduced signatures and increased upgradeability.

A full scale Land Based Engineering Site (LBES) was constructed at the Advanced Propulsion and Power Generation Test Site (APPGTS) of the Naval Surface Warfare Center, Carderock Division – Ship Systems Engineering Station (NSWCCD-SSES) in Philadelphia, Pa, to demonstrate the system architecture and feasibility of chosen technologies for a warship application. This paper will describe the IPS, test site construction, and test operational experience with a GE LM2500 engine, utilizing a Woodward Governor Company (WGC) MicroNet controller, as the prime mover for the main generator set.
Development of Metrological NDE Methods for Microturbine Ceramic Components
Authors: Lee H.-R. , Ellingson W. A.
Published: August 2014

In this work, X-ray computed tomographic imaging technology with high spatial resolution has been explored for metrological applications to Si3N4 ceramic turbine wheels. X-ray computed tomography (XCT) data were acquired by a charge-coupled device detector coupled to an image intensifier. Cone-beam XCT reconstruction algorithms were used to allow full-volume data acquisition from the turbine wheels. Special software was developed so that edge detection and complex blade contours could be determined from the XCT data. The feasibility of using the XCT for dimensional analyses was compared with that of a coordinate-measuring machine (CMM). Details of the XCT system, data acquisition, and dimensional comparisons will be presented. Comparison between XCT and CMM dimensions shows that the 3D XCT data have an accuracy of ± 0.2 mm in all three axis whereas the CMM data have an accuracy of ± 0.5 mm in the horizontal plane and ± 0.025 mm in the vertical plane.
The Evaluation of CFCC Liners After Field Testing in a Gas Turbine — II
Authors: Miriyala Narendernath , Price Jeffrey R.
Published: August 2014

Under the Ceramic Stationary Gas Turbine Program sponsored by the U. S. Department of Energy, Solar Turbines Incorporated has successfully designed and developed CFCC (SiC/SiC) combustor liners. Their potential for low emissions has been demonstrated in five field-engine tests for a total duration of over 10000 hours, with over 5000 hours on a CVI liner without EBC. The durability of the SiC/SiC liners was limited primarily by the long-term stability of SiC in a combustion environment. The evaluation of the SiC/SiC liners after the fourth field test is discussed in this paper.
Sector Testing of Cooled Silicon Nitride Ceramic HPT Vanes for the FT8 Aeroderivative Engine
Authors: Holowczak John E. , Bornemisza Tibor G. , Day William H.
Published: August 2014

Impingement cooled and vented silicon nitride turbine vanes were designed for the Pratt & Whitney/Turbo Power and Marine FT8 Aeroderivative stationary engine. The vanes were installed and tested in an FT8 based combustor sector rig under pressure and temperature conditions identical to those seen in an actual engine. The design methodology employed, the fabrication difficulties encountered, and the results of initial sector rig demonstration testing are reviewed.
Systematic Evaluation of US Navy LM2500 Gas Turbine Condition
Authors: Thompson Bruce D. , Wainscott Ben
Published: August 2014

From an operational availability stand point, the US Navy is interested in the short term reliability of its ship based LM2500 gas turbine engines. That is the likelihood that an engine will operate successfully through a six-month deployment (usually 1500 to 2000 operational hours). From a maintenance and cost of ownership standpoint both the short term and long term reliability are of concern. Long term reliability is a measure in time (in operating hours) between engine removals. To address these requirements US Navy Fleet support maintenance activities employ a system of tests and evaluations to determine the likelihood that an LM2500 will meet its short and long-term goals. The lowest level inspection is the pre deployment inspection, which attempts to identify primarily mechanical faults with the engine. Gas Turbine Bulletin inspections are used to determine if predefined wear out modes exists. Performance evaluations can be performed which determine the ability of the LM2500 and its control system to meet expected power requirements. Lube oil system data can be analyzed to determine if excessive leakage or excessive scavenge temperatures exist. Engine vibration characteristics can be reviewed to identify the source of both synchronous and non-synchronous vibration and determine if corrective measures need to be taken. This paper will discuss how the lowest level inspections feed the more sophisticated analysis and how these inspections and evaluations work to provide a systematic method of insuring both short and long term LM2500 reliability.
MCTP system model based on linear programming optimization of apertures obtained from sequencing patient image data maps
Authors: Ureba A. , Salguero F. J. , Barbeiro A. R. , Jimenez‐Ortega E. , Baeza J. A. , Miras H. , Linares R. , Perucha M. , Leal A.
Published: August 2014

Purpose:

The authors present a hybrid direct multileaf collimator (MLC) aperture optimization model exclusively based on sequencing of patient imaging data to be implemented on a Monte Carlo treatment planning system (MC‐TPS) to allow the explicit radiation transport simulation of advanced radiotherapy treatments with optimal results in efficient times for clinical practice.

Methods:

The planning system (called CARMEN) is a full MC‐TPS, controlled through aMATLAB interface, which is based on the sequencing of a novel map, called “biophysical” map, which is generated from enhanced image data of patients to achieve a set of segments actually deliverable. In order to reduce the required computation time, the conventional fluence map has been replaced by the biophysical map which is sequenced to provide direct apertures that will later be weighted by means of an optimization algorithm based on linear programming. A ray‐casting algorithm throughout the patient CT assembles information about the found structures, the mass thickness crossed, as well as PET values. Data are recorded to generate a biophysical map for each gantry angle. These maps are the input files for a home‐made sequencer developed to take into account the interactions of photons and electrons with the MLC. For each linac (Axesse of Elekta and Primus of Siemens) and energy beam studied (6, 9, 12, 15 MeV and 6 MV), phase space files were simulated with the EGSnrc/BEAMnrc code. The dose calculation in patient was carried out with the BEAMDOSE code. This code is a modified version of EGSnrc/DOSXYZnrc able to calculate the beamlet dose in order to combine them with different weights during the optimization process.

Results:

Three complex radiotherapy treatments were selected to check the reliability of CARMEN in situations where the MC calculation can offer an added value: A head‐and‐neck case (Case I) with three targets delineated on PET/CT images and a demanding dose‐escalation; a partial breast irradiation case (Case II) solved with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave‐shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements.

Conclusions:

A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time.
Strength Training Affects Lower Extremity Gait Kinematics, Not Kinetics, in People With Diabetic Polyneuropathy
Authors: Melai Tom , Schaper Nicolaas C. , IJzerman T. Herman , Willems Paul J.B. , de Lange Ton L.H. , Meijer Kenneth , Lieverse Aloysius G. , Savelberg Hans H.C.M.
Published: August 2014

Increased forefoot loading in diabetic polyneuropathy plays an important role in the development of plantar foot ulcers and can originate from alterations in muscle strength, joint moments and gait pattern. The current study evaluated whether strength training can improve lower extremity joint moments and spatiotemporal gait characteristics in patients with diabetic polyneuropathy. An intervention group receiving strength training during 24 weeks and a control group receiving no intervention. Measurements were performed in both groups at t = 0, t = 12, t = 24 and t = 52 weeks at an individually preferred and standardized imposed gait velocity. The strength training did not affect the maximal amplitude of hip, knee and ankle joint moments, but did result in an increase in stance phase duration, stride time and stride length of approximately 5%, during the imposed gait velocity. In addition, both groups increased their preferred gait velocity over one year. Future longitudinal studies should further explore the possible effects of strength training on spatiotemporal gait characteristics. The current study provides valuable information on changes in gait velocities and the progressive lower extremity problems in patients with polyneuropathy.
Distance and Slope Constraints: Adaptation and Variability in Golf Putting
Authors: Dias Gonçalo , Couceiro Micael S. , Barreiros João , Clemente Filipe M. , Mendes Rui , Martins Fernando M.L.
Published: August 2014

The main objective of this study is to understand the adaptation to external constraints and the effects of variability in a golf putting task. We describe the adaptation of relevant variables of golf putting to the distance to the hole and to the addition of a slope. The sample consisted of 10 adult male (33.80 ± 11.89 years), volunteers, right handed and highly skilled golfers with an average handicap of 10.82. Each player performed 30 putts at distances of 2, 3 and 4 meters (90 trials in Condition 1). The participants also performed 90 trials, at the same distances, with a constraint imposed by a slope (Condition 2). The results indicate that the players change some parameters to adjust to the task constraints, namely the duration of the backswing phase, the speed of the club head and the acceleration at the moment of impact with the ball. The effects of different golf putting distances in the no-slope condition on different kinematic variables suggest a linear adjustment to distance variation that was not observed when in the slope condition.
Draft Genome Sequence of Pasteurella multocida subsp.
multocida
B:2 Strain VTCCBAA264 Isolated from
Bubalus bubalis
in North India
Authors: Vaid R. K. , Shanmugasundaram K. , Boora Ashok , Bera B. C. , Shukla B. N. , Anand Taruna , Singha Harisankar , Riyesh Thachamvally , Virmani N. , Barua S. , Ahir V. B. , Koringa P. G. , Sajnani M. R. , Bhat Vaibhav D. , Rana N. , Singh K. P. , Malik P. , Singh R. K. , Joshi C. G.
Published: August 2014

The
Pasteurella multocida
subsp.
multocida
B:2 serotype causes hemorrhagic septicemia in bubalines with high morbidity and mortality in the Indian subcontinent. We report the draft genome sequence of
Pasteurella multocida
strain VTCCBAA264 isolated from the small-intestine of a buffalo calf that died of high fever.
A THEOREM ON REPEATED FILTERING
Authors: DJORDJEVIĆ ANTONIJE , TOŠIĆ DEJAN , DJURIĆ-JOVIČIĆ MILICA
Published: August 2014

Repeatedly passing a signal through a low-pass filter may resemble using a Gaussian or hyper-Gaussian filter. Conditions are established for this resemblance. A theorem on approximation of Gaussian and hyper-Gaussian filters by a cascade of simple filters is established and the corresponding phase and group delay characteristics are analyzed. The theorem and the analysis are exemplified by cascading moving-average filters and the first-order Butterworth filters.
New characterization of two-state normal distribution
Authors: Ejsmont Wiktor
Published: August 2014

In this paper we give a purely noncommutative criterion for the characterization of two-state normal distribution. We prove that families of two-state normal distribution can be described by relations which is similar to the conditional expectation in free probability, but has no classical analogue. We also show a generalization of Bożejko, Leinert and Speichers formula from Ref. 10 (relating moments and noncommutative cumulants).
The free logarithmic Sobolev and the free transportation cost inequalities by time integrations
Authors: Nemoto Aya , Yoshida Hiroaki
Published: August 2014

In this paper, we shall revisit the free analogues of the logarithmic Sobolev and the transportation cost inequalities for one-dimensional case by time integrations. We consider time evolutions by the free Fokker–Planck equation and calculate the time derivative of the 2-Wasserstein distance with the optimal mass transportation, from which some differential inequalities can be derived. The convergence to the equilibrium in the relative free entropy is discussed, and the free transportation cost and the free logarithmic Sobolev inequalities can be obtained by time integrations.
In-situ Soil Moisture Sensing
Authors: Wu Xiaopei , Wang Qingsi , Liu Mingyan
Published: August 2014

We consider the problem of monitoring soil moisture evolution using a wireless network of in-situ underground sensors. To reduce cost and prolong lifetime, it is highly desirable to rely on fewer measurements and estimate with higher accuracy the original signal (the temporal evolution of soil moisture). In this article, we explore the use of results from the theory of sparse sampling, including Compressive Sensing (CS) and Matrix Completion (MC), in this application context. We first consider the problem of reconstructing the soil moisture process at a single location using CS. Our physical constraint leads to very sparse measurement matrices, which makes finding a suitable representation basis very challenging: it needs to make the underlying signal sufficiently sparse while at the same time being sufficiently incoherent with the measurement matrix, two common preconditions for CS techniques to work well. We construct a representation basis by exploiting unique features of soil moisture evolution and show that this basis attains a very good tradeoff between its ability to sparsify the signal and its incoherence with measurement matrices that are consistent with our physical constraints. We next consider the problem of jointly reconstructing soil moisture processes at multiple locations, assuming sparse measurements can be taken at each location. We show that the spatial soil moisture process enjoys a low-rank property, a priority for MC. Accordingly, we introduce a spatiotemporal measurement matrix and apply the MC framework to reconstruct the soil moisture field. Extensive numerical evaluation is performed on both real, high-resolution soil moisture data and simulated data and through comparison with a closed-loop scheduling approach. Our results demonstrate that, for a single location, a uniform measurement scheduling followed by CS recovery results in a very nice tradeoff between estimation accuracy, sampling rate, flexibility, and feasibility in implementation. When multiple locations are available, our results show that joint reconstruction using MC in general produces better estimation accuracy than using a single location alone, but it requires the use of independent and random measurement schedules across locations. We also show that these sparse sampling techniques can be augmented so as to be robust against sporadic data outliers/corruption caused by, for example, intermittent sensor faults.
ChoiceNet
Authors: Wolf Tilman , Griffioen James , Calvert Kenneth L. , Dutta Rudra , Rouskas George N. , Baldin Ilya , Nagurney Anna
Published: August 2014

The Internet has been a key enabling technology for many new distributed applications and services. However, the deployment of new protocols and services in the Internet infrastructure itself has been sluggish, especially where economic incentives for network providers are unclear. In our work, we seek to develop an "economy plane" for the Internet that enables network providers to offer new network-based services (QoS, storage, etc.) for sale to customers. The explicit connection between economic relationships and network services across various time scales enables users to select among service alternatives. The resulting competition among network service providers will lead to overall better technological solutions and more competitive prices. In this paper, we present the architectural aspects of our ChoiceNet economy plane as well as some of the technological problems that need to be addressed in a practical deployment.
Mobile offloading in wireless ad hoc networks
Authors: Kalejaiye Gabriel B.T. , Rondina Joao A.S.R. , Albuquerque Leonardo V.V.L. , Pereira Tais L. , Campos Luiz F.O. , Melo Raphael A.S. , Mascarenhas Daniel S. , Carvalho Marcelo M.
Published: August 2014

This paper describes a strategy that was designed, implemented, and presented at the Mobile Ad Hoc Networking Interoperability and Cooperation (MANIAC) Challenge 2013. The theme of the challenge was "Mobile Data Offloading," and consisted on developing and comparatively evaluating strategies to offload infrastructure access points via customer ad hoc forwarding using handheld devices. According to the challenge rules, a hop-by-hop bidding contest should decide the path of each data packet towards its destination. Consequently, each team should rely on other teams' willingness to forward packets for them in order to get their traffic across the network. Following these rules, this paper proposes a strategy that is based on the concept of how "tight" a node is to successfully deliver a packet to its destination within a given deadline. This "tightness" idea relies on a shortest-path analysis of the underlying network graph, and it is used to define three sub-strategies that specify a) how to participate in an auction; b) how to announce an auction; and c) how to decide who wins the announced auction. The proposed strategy seeks to minimize network resource utilization and to promote cooperative behavior among participant nodes.
Lung ventilation injures areas with discrete alveolar flooding, in a surface tension-dependent fashion
Authors: Wu (吴右) You , Kharge Angana Banerjee , Perlman Carrie E.
Published: August 2014

With proteinaceous-liquid flooding of discrete alveoli, a model of the edema pattern in the acute respiratory distress syndrome, lung inflation over expands aerated alveoli adjacent to flooded alveoli. Theoretical considerations suggest that the overexpansion may be proportional to surface tension, T. Yet recent evidence indicates proteinaceous edema liquid may not elevate T. Thus whether the overexpansion is injurious is not known. Here, working in the isolated, perfused rat lung, we quantify fluorescence movement from the vasculature to the alveolar liquid phase as a measure of overdistension injury to the alveolar-capillary barrier. We label the perfusate with fluorescence; micropuncture a surface alveolus and instill a controlled volume of nonfluorescent liquid to obtain a micropunctured-but-aerated region (control group) or a region with discrete alveolar flooding; image the region at a constant transpulmonary pressure of 5 cmH2O; apply five ventilation cycles with a positive end-expiratory pressure of 0–20 cmH2O and tidal volume of 6 or 12 ml/kg; return the lung to a constant transpulmonary pressure of 5 cmH2O; and image for an additional 10 min. In aerated areas, ventilation is not injurious. With discrete alveolar flooding, all ventilation protocols cause sustained injury. Greater positive end-expiratory pressure or tidal volume increases injury. Furthermore, we determine T and find injury increases with T. Inclusion of either plasma proteins or Survanta in the flooding liquid does not alter T or injury. Inclusion of 2.7–10% albumin and 1% Survanta together, however, lowers T and injury. Contrary to expectation, albumin inclusion in our model facilitates exogenous surfactant activity.
Cell-Cycle Reprogramming for PI3K Inhibition Overrides a Relapse-Specific C481SBTKMutation Revealed by Longitudinal Functional Genomics in Mantle Cell Lymphoma
Authors: Chiron David , Di Liberto Maurizio , Martin Peter , Huang Xiangao , Sharman Jeff , Blecua Pedro , Mathew Susan , Vijay Priyanka , Eng Ken , Ali Siraj , Johnson Amy , Chang Betty , Ely Scott , Elemento Olivier , Mason Christopher E. , Leonard John P. , Chen-Kiang Selina
Published: August 2014

Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib in mantle cell lymphoma (MCL), acquired resistance is common. By longitudinal integrative whole-exome and whole-transcriptome sequencing and targeted sequencing, we identified the first relapse-specific C481S mutation at the ibrutinib binding site of BTK in MCL cells at progression following a durable response. This mutation enhanced BTK and AKT activation and tissue-specific proliferation of resistant MCL cells driven by CDK4 activation. It was absent, however, in patients with primary resistance or progression following transient response to ibrutinib, suggesting alternative mechanisms of resistance. Through synergistic induction of PIK3IP1 and inhibition of PI3K–AKT activation, prolonged early G1 arrest induced by PD 0332991 (palbociclib) inhibition of CDK4 sensitized resistant lymphoma cells to ibrutinib killing when BTK was unmutated, and to PI3K inhibitors independent of C481S mutation. These data identify a genomic basis for acquired ibrutinib resistance in MCL and suggest a strategy to override both primary and acquired ibrutinib resistance.

Significance: We have discovered the first relapse-specific BTK mutation in patients with MCL with acquired resistance, but not primary resistance, to ibrutinib, and demonstrated a rationale for targeting the proliferative resistant MCL cells by inhibiting CDK4 and the cell cycle in combination with ibrutinib in the presence of BTKWT or a PI3K inhibitor independent of BTK mutation. As drug resistance remains a major challenge and CDK4 and PI3K are dysregulated at a high frequency in human cancers, targeting CDK4 in genome-based combination therapy represents a novel approach to lymphoma and cancer therapy. Cancer Discov; 4(9); 1022–35. ©2014 AACR.

This article is highlighted in the In This Issue feature, p. 973
What does the Ox Know in Isa 1:3a?
Authors: Berman Joshua
Published: August 2014

Many modern expositors of the image of the knowing ox in Isa 1:3a do not address the pastoral reality that animates the image. Drawing from the glosses of two medieval rabbinic exegetes and from studies of bovine ethology this study explores the suggestions that have been raised concerning this reality. The study probes the implications of each suggestion for a fuller understanding of the oracle of Isa 1:2-3 and its place at the beginning of the book of Isaiah.
Velloziaceae in honorem appellatae
Authors: Mello-Silva Renato , MENEZES NANUZA LUIZA DE
Published: August 2014

Four new species of Vellozia are described and named after people linked to Velloziaceae and Brazilian botany. Vellozia everaldoi, V. giuliettiae, V. semirii and V. strangii are endemic to the Diamantina Plateau in Minas Gerais, Brazil. Vellozia giuliettiae and V. semirii are small species that share characteristics that would assign them to Vellozia sect. Xerophytoides, which include an ericoid habit with no leaf furrows and six stamens. Vellozia everaldoi, although a small, ericoid species, could not be placed in that section because it has conspicuous furrows, although it is considered closely related to species of that section. The fourth species, V. strangii, is a relative large species closely related to V. hatschbachii. Descriptions and illustrations of the species are followed by a discussion of their characteristics and putative relationships.
Oyedaea bahiensis, a new synonym in the Brazilian Heliantheae (Asteraceae)
Authors: Magenta Mara ANGELINA GALVÃO , Loeuille Benoit
Published: August 2014

The taxonomic status of Oyedaea bahiensis is clarified. This name is placed here to the synonymy of Aspilia martii, which is described and illustrated. The names Oyedaea angustifolia and O. bahiensis are lectotypified.
Heterodermia upretii, a new species from India (Physciaceae, Ascomycota)
Authors: Joshi Yogesh , Upadhyay Shashi , Chandra Krishna
Published: August 2014

Taxonomic studies on the lichen genus Heterodermia in India revealed a hitherto unknown species, which is here described as new: H. upretii Y. Joshi, S. Upadhyay & K. Chandra. It is characterized by a grayish, ±pruinose thallus, corticated lower surface, yellowish-orange P+ red medulla and Polyblastidium-type ascospores with sporoblastidia. The species is reported from temperate regions of Champawat and Pithoragarh districts of Kumaun Himalaya and was found colonizing rocks, barks and twigs of various trees. Description and figures are provided and the new taxon is compared with similar Heterodermia species.
Pethia longicauda, a new species of barb (Teleostei: Cyprinidae)
from the northern Western Ghats, India
Authors: KATWATE UNMESH , PAINGANKAR MANDAR S. , RAGHAVAN RAJEEV , DAHANUKAR NEELESH
Published: August 2014

Pethia longicauda, a new cyprinid fish, is described from Hiranyakeshi River, Krishna drainage, Maharashtra, India. It can be distinguished from congeners based on a combination of characters including: a long caudal peduncle, incomplete lateral line, absence of barbels, upper lip thick and fleshy, distinct lateral fold on snout, 22–24 scales in lateral series, 5–6 lateral-line pored scales, nine predorsal scales, 9–10 prepelvic scales, 15–17 preanal scales, ½3/1/3½ transverse scales, 11–15 pairs of serrae on the distal half of the last unbranched dorsal-fin ray, 11–13 branched pectoral fin rays, 4+26 total vertebrae, 4+5 predorsal vertebrae, 4+13 abdominal and 13 caudal vertebrae, body iridescent silver in color with a black humeral spot, two black blotches on caudal peduncle and dorsal fin usually without any color bands or blotches but in breeding males with two rows of minute, indistinct black spots.
Research methodology for evaluation of top-of-rail friction management in Australian heavy haul networks
Authors: Spiryagin Maksym , Sajjad Mojibul , Nielsen Dwayne , Sun Yan Quan , Raman Dhamodharan , Chattopadhyay Gopinath
Published: August 2014

Managing the coefficient of friction at the wheel/rail interface through wheel flange/gauge face lubrication is an accepted practice in railway systems. However, the coefficient of friction between the top of rail and wheel tread is not well addressed using this method, with traction, braking and some steering forces causing significant rail and wheel damage. Top-of- rail friction management uses friction modifiers to control the coefficient of friction within a defined range, and is being used in some North American rail networks with beneficial results. In Australia, there has been limited use of top-of-rail lubrication and where it is applied, it is mainly utilised to improve steering forces and mitigate wheel squeal. This research project sought a holistic understanding of top-of-rail lubrication and management of wheel/rail friction in the Australian context. A systematic approach for experimentation and analysis of the application of a friction modifier was developed in this study. The approach utilised an engineering analysis based on experimental results and publications and a numerical study for three-dimensional analysis. Vehicle system dynamics and wheel/rail operating conditions were then modelled through GENSYS simulation to understand variations in wear index with respect to friction conditions at the wheel/rail interface.
Validation and Reproducibility of a Biplanar Imaging System Versus Conventional Radiography of Foot and Ankle Radiographic Parameters
Authors: Rungprai Chamnanni , Goetz Jessica E. , Arunakul Marut , Gao Yubo , Femino John E. , Amendola Annunziato , Phisitkul Phinit
Published: August 2014

Background:

Diagnosis of foot deformities is frequently supported by objective measures of bony alignment made on AP and lateral weight-bearing radiographs. The EOS biplanar imaging system has the capability of simultaneously capturing orthogonal AP and lateral images of the foot during weight-bearing with reduced radiation exposure. The purpose of this study was to evaluate the validity and reproducibility of common foot and ankle radiographic measurements made on images acquired with the EOS biplanar imaging system.

Methods:

Fifty consecutive patients indicated for foot and ankle realignment surgeries were enrolled. Radiographic studies included conventional AP and lateral ankle weight-bearing radiographs and long-leg AP and lateral weight-bearing images acquired using the EOS system with both a staggered feet and a nonstaggered feet position. Sixteen radiographic parameters of foot, ankle, and lower limb alignment were measured by 2 blinded observers, with 1 observer repeating all measurements 6 weeks later. Inter- and intraobserver reliability was assessed using intraclass correlation coefficients. Between-group comparison was assessed using Pearson correlation coefficients, ANOVA, and paired t-tests.

Results:

There was no statistically significant difference in any commonly used foot and ankle radiographic parameters measured on conventional radiographs or EOS images acquired with staggered and nonstaggered feet (ANOVA P = .792 to .997 and paired t tests P = .067 to .977). However, the staggered foot position resulted in significantly different limb length measurements in the rear leg ( P = .000 to .049). Intra- and interrater reliabilities of limb alignment measurements from EOS system images were excellent in both foot positions (ICC = .938 to 1.000).

Conclusion:

Images acquired using EOS biplanar imaging system allowed for valid and reliable measurement of commonly used foot and ankle radiographic parameters; however, the staggered foot position required for simultaneous imaging of both feet in the lateral view affected limb length measurements in the rear leg.

Level of Evidence:

Level II, prospective comparative study.
Ferrite recrystallisation and characteristics of non-recrystallised ferrite grains in Ti added low carbon steels
Authors: Ogawa T.
Published: August 2014

The progress of ferrite recrystallisation in low carbon steel was slower than in ultralow carbon steel. The hardness of the non-recrystallised ferrite grains gradually decreased with increasing annealing time in ultralow carbon steel, but gradually increased with increasing annealing time in low carbon steel. The amount of Ti containing precipitates increased slightly during annealing in ultralow carbon steel, but increased remarkably with increasing annealing time in low carbon steel. These results suggest that the softening of non-recrystallised ferrite grains during annealing in ultralow carbon steel may reflect the progress of recovery and the Ostwald ripening of Ti containing precipitates formed during annealing. In contrast, the hardening of non-recrystallised ferrite grains in low carbon steel may be due to the precipitation hardening of TiC formed during annealing.
Oxidation resistance of novel multilayer coatings for gas turbine components
Authors: Gao F. , Yang Q. , Liu R. , Huang X.
Published: August 2014

This article presents a study of the oxidation behaviour of two multilayer coatings, denoted as MC I and MC II, respectively, which are designed with a three-layer architecture: a Cr–Si barrier layer on the IN738 substrate, a NiCrAlY intermediate layer, and an aluminised top layer. The emphasis of this research is on the total amount of oxide scales formed and the residual oxide scales on the coatings with various combinations among the three layers to investigate the effects of each layer and the interactions between the layers on the oxidation resistance of the coatings. The difference between the two multilayer coatings is that the Al content in the top layer of MC II is twice as much as that in the top layer of MC I. The coatings are fabricated through a combination of plasma spray and pack cementation processes, and then experience oxidation test at 1050°C for 1000 h. The average thicknesses of the oxide scales are around 15 and 45 μm for MC I and MC II, respectively. The experimental results are modelled using the analysis of variance. Two models for the volume of total oxide scales and the ratio of the volume of spalled oxide scales to the volume of total oxide scales, are proposed to study the effects of the coating layers on the formation and spallation of oxide scales, which directly affect the oxidation resistance of the coatings. The experimental and analytical results demonstrate that the Cr–Si layer and its interactions with the other coating layers affect the spallation of oxide scales the most among the three layers. It prevents Al and Cr from diffusing into the substrate. The interaction between the Cr–Si layer and the NiCrAlY layer, and the increase in Al/Ni ratio of the aluminide top layer, promote the formation of oxide scales and also minimise the spallation of oxide scales.
Effects of atmospheric pressure plasma JET treatment on aluminium alloys
Authors: Brunelli K. , Pezzato L. , Napolitani E. , Gross S. , Magrini M. , Dabalà M.
Published: August 2014

In this paper, the effect of surface treatments carried out with an atmospheric pressure plasma jet, generated by air, on the passive film of AA1071 and AA2024 was investigated. The samples of the aluminium alloys, before and after the surface plasma treatments, were analysed by secondary ions mass spectrometry depth profiling and by X-ray photoelectron spectroscopy. Potentiodynamic anodic polarisation tests and electrochemical impedance spectroscopy measurements were carried out to study the influence of the surface plasma treatments on the corrosion resistance properties of the Al alloys. The plasma treatments induced the oxidation of the surface and the formation of a thicker and denser passive layer, which exhibited higher corrosion resistance than the native film.
Effect of crystallisation on electrochemical properties of arc sprayed FeNiCrBSiNbW coatings
Authors: Lin J. R. , Wang Z. H. , Lin P. H. , Cheng J. B. , Zhang X. , Hong S.
Published: August 2014

FeNiCrBSiNbW coatings were prepared using a twin wires arc spraying process and were subsequently annealed at 450, 550 and 650°C for 1 h to obtain coatings with different crystallisation. The effect of crystallisation on the electrochemical properties of the coatings was investigated. Transformation of the amorphous phase to crystalline phases of α-(Fe,Cr), Fe3B and Fe23B6 occurred when the as sprayed coating was treated at 650°C. Open circuit potential tests, potentiodynamic polarisation tests and electrochemical impendence spectroscopy were employed to investigate the corrosion resistance of the coatings in 3·5 wt-%NaCl solution. The results showed that the corrosion resistance of the coatings decreased with increasing annealing temperature, and the as sprayed coating exhibited the best corrosion resistance among the four kinds of coatings. This was attributed to the high amorphous phase content and the absence of borides such as Fe3B and Fe23B6 phases in the coating.
Development of Al oxide PVD coatings against metal dusting
Authors: Uribe E. , Salas O. , Melo-Máximo D. , Oseguera J. , Lepienski C. M. , Torres R. D. , Souza R. M.
Published: August 2014

Al oxide thin films were deposited on 304L stainless steel substrates to investigate their potential as protective coatings in metal dusting environments. Deposition of the films was carried out by d.c. reactive magnetron sputtering varying feeding mode of O2 flow and application of a Cr interlayer. The response to metal dusting of coated and uncoated substrates was evaluated by thermogravimetry in an atmosphere of CH4+H2+residual oxygen at 1073 K for 20 h. The results indicated that these types of coatings can effectively protect the 304L steel in these conditions. The protection was associated to good adhesion provided by the Cr interlayer and the role of the Al oxide as a barrier for diffusion. Improvement of the present coatings can be achieved within magnetron sputtering deposition techniques.
Neutrophils with myeloid derived suppressor function deplete arginine and constrain T cell function in septic shock patients
Authors: Darcy Christabelle J , Minigo Gabriela , Piera Kim A , Davis Joshua S , McNeil Yvette R , Chen Youwei , Volkheimer Alicia D , Weinberg J Brice , Anstey Nicholas M , Woodberry Tonia
Published: August 2014

Introduction

Impaired T cell function in sepsis is associated with poor outcome, but the mechanisms are unclear. In cancer, arginase-expressing myeloid derived suppressor cells (MDSCs) deplete arginine, impair T cell receptor CD3 zeta-chain expression and T cell function and are linked to poor clinical outcome, but their role during acute human infectious disease and in particular sepsis remains unknown. Hypoarginemia is prevalent in sepsis. This study aimed to determine whether neutrophils that co-purify with PBMC express arginase, and if arginine depletion constrains T cell CD3 zeta-chain expression and function in human sepsis.

Methods

Using flow cytometry, cell culture, HPLC, arginase activity and mRNA detection, our study examined whether neutrophils, with reduced buoyant density isolated in the Ficoll interface, metabolise L-arginine and suppress T cell proliferation in sepsis. A total of 35 sepsis patients (23 with septic shock) and 12 hospital controls in a tertiary referral hospital in tropical Australia were evaluated.

Results

Only sepsis patients had interphase neutrophils, neutrophils co-purifying with mononuclear cells (≤1.077 specific gravity). The percentage of interphase neutrophils in sepsis was proportional to sepsis severity and correlated with plasma IL-6 concentrations. Ex vivo, sepsis-derived interphase neutrophils expressed arginase, metabolised culture L-arginine and suppressed T cell proliferation and CD3 zeta-chain expression. In vivo, in septic shock there was a longitudinal inverse association between interphase neutrophil number and CD3 zeta-chain expression. Depletion or inhibition of interphase neutrophils in vitro restored zeta-chain expression and T cell function.

Conclusions

For the first time during an acute human infection, interphase neutrophils that express arginase were found to circulate in sepsis, in proportion to disease severity. These neutrophil-MDSCs impair T cell CD3 zeta-chain expression and T cell function via L-arginine metabolism, and likely contribute to the T cell dysfunction seen in sepsis. Modulation of neutrophil-MDSC or their downstream effects warrant consideration as targets for novel adjunctive therapies in sepsis.
Vaccinations for winter escapes
Authors: Grieve Sandra
Published: August 2014

IMMUNISATION

Nurses play a key role in advising on the correct immunisations for travellers planning a winter break abroad, explains Sandra Grieve
Mid-to long-term results of revision total hip replacement in patients aged 50 years or younger
Authors: Lee P. T. H. , Lakstein D. L. , Lozano B. , Safir O. , Backstein J. , Gross A. E.
Published: August 2014

Revision total hip replacement (THR) for young patients is challenging because of technical complexity and the potential need for subsequent further revisions. We have assessed the survivorship, functional outcome and complications of this procedure in patients aged <  50 years through a large longitudinal series with consistent treatment algorithms. Of 132 consecutive patients (181 hips) who underwent revision THR, 102 patients (151 hips) with a mean age of 43 years (22 to 50) were reviewed at a mean follow-up of 11 years (2 to 26) post-operatively. We attempted to restore bone stock with allograft where indicated. Using further revision for any reason as an end point, the survival of the acetabular component was 71% (sd 4) and 54% (sd 7) at ten- and 20 years. The survival of the femoral component was 80% (sd 4) and 62% (sd 6) at ten- and 20 years. Complications included 11 dislocations (6.1%), ten periprosthetic fractures (5.5%), two deep infections (1.1%), four sciatic nerve palsies (2.2%; three resolved without intervention, one improved after exploration and freeing from adhesions) and one vascular injury (0.6%). The mean modified Harris Hip Score was 41 (10 to 82) pre-operatively, 77 (39 to 93) one year post-operatively and 77 (38 to 93) at the latest review.

This overall perspective on the mid- to long-term results is valuable when advising young patients on the prospects of revision surgery at the time of primary replacement.

Cite this article: Bone Joint J 2014;96-B:1047–51.
A retrospective analysis of the use of cannulated compression screws and a vascularised iliac bone graft in the treatment of displaced fracture of the femoral neck in patients aged < 50 years
Authors: Dewei Z. , Xiaobing Y.
Published: August 2014

There is a high risk of the development of avascular necrosis of the femoral head and nonunion after the treatment of displaced subcapital fractures of the femoral neck in patients aged < 50 years. We retrospectively analysed the results following fixation with two cannulated compression screws and a vascularised iliac bone graft. We treated 18 women and 16 men with a mean age of 38.5 years (20 to 50) whose treatment included the use of an iliac bone graft based on the ascending branch of lateral femoral circumflex artery. There were 20 Garden grade III and 14 grade IV fractures. Clinical and radiological outcomes were evaluated. The mean follow-up was 5.4 years (2 to 10). In 30 hips (88%) union was achieved at a mean of 4.4 months (4 to 6). Nonunion occurred in four hips (12%) and these patients had a mean age of 46.5 years (42 to 50) and underwent revision to a hip replacement six months after operation. The time to union was dependent on age with younger patients achieving earlier union (p < 0.001). According to the Harris hip score which was available for 27 of the 30 hips with satisfactory union, excellent results were obtained in 15 (score ≥ 90 points), fair in ten (score 80 to 90 points), and poor in two hips (≤ 80 points). One patient aged 48 years developed avascular necrosis of femoral head six years after operation and underwent total hip replacement.

The management of displaced subcapital fractures of the femoral neck, in patients aged <  50 years, with two cannulated compression screws and an iliac bone graft based on the ascending branch of lateral femoral circumflex artery, gives satisfactory results with a low rate of complication including avascular necrosis and nonunion.

Cite this article: Bone Joint J 2014;96-B:1024–8.
The influence of the choice of closing wedge angle on leg length discrepancy after proximal femoral varus osteotomy
Authors: Segaren N. , Abdul-Jabar H. B. , Hashemi-Nejad A.
Published: August 2014

Proximal femoral varus osteotomy improves the biomechanics of the hip and can stimulate normal acetabular development in a dysplastic hip. Medial closing wedge osteotomy remains the most popular technique, but is associated with shortening of the ipsilateral femur.

We produced a trigonometric formula which may be used pre-operatively to predict the resultant leg length discrepancy (LLD). We retrospectively examined the influence of the choice of angle in a closing wedge femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male, mean age six years, (3 to 21), 96% caucasian) over a 15-year period (1998 to 2013). A total of 16 of these patients were excluded due to under or over varus correction. The patients were divided into three age groups: paediatric (< 10 years), adolescent (10 to 16 years) and adult (> 16 years). When using the same saw blades as in this series, the results indicated that for each 10° of angle of resection the resultant LLD equates approximately to multiples of 4 mm, 8 mm and 12 mm in the three age groups, respectively.

Statistical testing of the 59 patients who had a complete set of pre- and post-operative standing long leg radiographs, revealed a Pearson’s correlation coefficient for predicted versus radiologically observed shortening when using a wedge of either 10° or 20° of 0.93 (p <  0.001). The 95% limits of agreement from the Bland–Altman analysis for this subgroup were –3.5 mm to +3.3 mm. It has been accepted that a 10 mm discrepancy is clinically acceptable.

This study identified a geometric model that provided satisfactory accuracy when using specific saw blades of known thicknesses for this formula to be used in clinical practice.

Cite this article: Bone Joint J 2014;96-B:1124–9
A prejudiced view
Authors: Monsell F. P.
Published: August 2014

The contemporary practice of orthopaedic surgery requires an evidence-based approach to support all medical and surgical interventions. In this essay, the author expresses a forthright, personal and somewhat prejudiced appeal to retain the legitimacy of clinical decision making in conditions that are rare, contain multiple variables, have a solution that generally works or has an unpredictable course.

Cite this article: Bone Joint J 2014;96-B:1002–4.