bluuebunny/crossref_metadata_2025 huggingface dataset:
Polysomnographic evaluation of non‐invasive ventilation in children with neuromuscular disease
Authors: Falsaperla Raffaele , Wenzel Anette , Pavone Piero , Di Mauro Caterina , Vitaliti Giovanna
Published: September 2013

Background and objective

In the last 20 years, research efforts have been focused on the use of non‐invasive ventilation (NIV) as a mean of avoiding tracheostomy in patients affected by neuromuscular diseases (NMD). Nocturnal NIV has been a particular focus as sleep is a risk factor for respiratory failure in NMD patients. The objective of our study was to evaluate the efficacy of nocturnal NIV in improving the respiratory function of NMD patients evaluated by polysomnography (PSG) and arterial blood gas (ABG) analysis parameters.

Methods

Ten children affected by NMD underwent PSG and ABG analysis evaluation at the onset of their respiratory failure and during nocturnal NIV therapy.

Results

We found a statistically significant improvement of the lowest oxygen desaturation (nadir SaO2), apnoea–hypopnoea index (AHI) and oxygen desaturation index (ODI) after NIV treatment in all patients. Mean SaO2 also improved, although this result was not statistical significant, while the percentage of episodes of desaturation with a SaO2 <90% and <80% decreased with a statistical significance (P < 0.0001).

After NIV, only one patient showed an episode of desaturation lasting more than 5 min (10.6 min length), and we also found an improvement of daytime blood gas parameters with a normalization of these indexes.

Conclusions

NIV was effective in improving respiratory parameters at night in patients affected by respiratory muscular weakness, as evaluated by PSG and ABG analysis.
The quintessential Christian tomb: saints, professors, and Riccio's tomb design
Authors: Carson Rebekah
Published: September 2013

This article examines Andrea Riccio's design of the Della Torre tomb monument in Verona – one of Riccio's major commissions that long merited further study. In this design the artist challenged the modes of contemporary funerary art. Although the absence of Christian iconography and the strict all'antica visual language may appear to break with the decorum of Christian funerary art, I argue that Riccio drew on an overtly Christian design – the tombs of saints. By drawing upon the typology of the tombs of saints, the structure of the Della Torre monument signalled to the viewer the didactic nature of Riccio's narrative programme. Understanding the design of the monument casts greater light on the tomb's programme and the sophisticated nature of Riccio's work.
Understanding Public Perceptions of Benefits and Risks of Childhood Vaccinations in the United States
Authors: Song Geoboo
Published: September 2013

In the face of a growing public health concern accompanying the reemerging threat of preventable diseases, this research seeks mainly to explain variations in the perceived benefits and risks of vaccinations among the general public in the United States. As Mary Douglas and Aaron Wildavsky's grid‐group cultural theory of risk perception claims, the analytical results based upon original data from a nationwide Internet survey of 1,213 American adults conducted in 2010 suggest that individuals’ cultural predispositions contribute to the formation of their perceptions pertaining to vaccine benefits and risks at both societal and individual levels, in conjunction with other factors suggested by previous risk perception literature, such as perceived prevalence of diseases, trust, knowledge level, and demographic characteristics. Those with a strong hierarch orientation tend to envision greater benefits and lesser risks and conceive of a relatively high ratio of benefit to risk when compared to other cultural types. By contrast, those with a strong fatalist tendency are inclined to emphasize risks and downplay benefits while conceiving of a low vaccination benefit‐risk ratio. Situated between hierarchs and fatalists, strong egalitarians are prone to perceive greater benefits, smaller risks, and a more positive benefit‐risk ratio than strong individualists.
New Predictive Marker for Hemodialysis Vascular Access Dysfunction
Authors: Kim Ji Dae , Bae Jae Ik , Won Je Hwan , Lee Jong Hoon , Oh Chang‐Kwon , Jung Hyuna , Lee Hyun Young
Published: September 2013

To examine the relationship between intra‐access pressures and vascular stenosis, we measured the total (pT) and static (pS) pressures and the severity of stenosis before and after percutaneous transluminal angioplasty (PTA). The dynamic pressure (△p) and static intra‐access pressure ratios (SIAPR) were calculated. We analyzed the clinical correlation of △p and SIAPR with the severity and location of stenosis, and searched potential predictive factors for the severity of stenosis using multivariate regression. While SIAPR was significantly decreased only in outflow stenosis after PTA (p < 0.0001), △p was significantly increased in both inflow and in outflow stenosis (p < 0.05). SIAPR was negatively correlated with the severity of stenosis only in outflow stenosis (p < 0.0001), and △p was significantly correlated with both inflow and outflow stenosis (p < 0.05). △p was an independent predictor for the severity of stenosis in both inflow and outflow stenosis (p < 0.05). Thus, our study suggests that △p may be more clinically useful than SIAPR not only in detecting access stenosis regardless of its location, but also providing information about the severity of stenosis.
Discrete Multicolour Random Mosaics with an Application to Network Extraction
Authors: van Lieshout M.N.M.
Published: September 2013

We introduce a class of random fields that can be understood as discrete versions of multicolour polygonal fields built on regular linear tessellations. We focus first on a subclass of consistent polygonal fields, for which we show Markovianity and solvability by means of a dynamic representation. This representation is used to design new sampling techniques for Gibbsian modifications of such fields, a class which covers lattice‐based random fields. A flux‐based modification is applied to the extraction of the field tracks network from a Synthetic Aperture Radar image of a rural area.
Testing for a Change of the Innovation Distribution in Nonparametric Autoregression: The Sequential Empirical Process Approach
Authors: Selk Leonie , Neumeyer Natalie
Published: September 2013

We consider a nonparametric autoregression model under conditional heteroscedasticity with the aim to test whether the innovation distribution changes in time. To this end, we develop an asymptotic expansion for the sequential empirical process of nonparametrically estimated innovations (residuals). We suggest a Kolmogorov–Smirnov statistic based on the difference of the estimated innovation distributions built from the first ⌊ns⌋and the last n − ⌊ns⌋ residuals, respectively (0 ≤ s ≤ 1). Weak convergence of the underlying stochastic process to a Gaussian process is proved under the null hypothesis of no change point. The result implies that the test is asymptotically distribution‐free. Consistency against fixed alternatives is shown. The small sample performance of the proposed test is investigated in a simulation study and the test is applied to a data example.
Comparison of the Mechanical Behaviour of Standard and Auxetic Foams by X‐ray Computed Tomography and Digital Volume Correlation
Authors: Pierron F. , McDonald S. A. , Hollis D. , Fu J. , Withers P. J. , Alderson A.
Published: September 2013

The tensile behaviour of standard and auxetic polyurethane foams are contrasted by digital volume correlation of 3D images collected by in situ X‐ray computed tomography (CT). It was found that subset sizes of 32 and 64 voxels for the auxetic and standard foams were optimal for strain resolutions in the order of 0.1%. For the standard foam, good uniformity of strain was observed at low strains giving a tangent Poisson's ratio of 0.5. Some heterogeneity of strain was observed at higher strains, which may be related to the fixtures. The behaviour of the auxetic foam was totally different, with strain being spatially heterogeneous with transverse strains both positive and negative but giving a negative Poisson's ratio on average. This suggests that the unfolding tendency of some groups of cells was higher than others because of the complex frozen starting microstructure. Further different methods of deriving Poisson's ratio gave different results. Besides revealing interesting microstuctural mechanisms of transverse straining, the study also shows digital volume correlation of tomography sequences to be the perfect tool to study complex mechanical behaviour of cellular materials.
An enhanced software tool to support better use of manure nutrients:MANNER‐NPK
Authors: Nicholson F. A. , Bhogal A. , Chadwick D. , Gill E. , Gooday R. D. , Lord E. , Misselbrook T. , Rollett A. J. , Sagoo E. , Smith K. A. , Thorman R. E. , Williams J. R. , Chambers B. J.
Published: September 2013

MANNER‐NPK(MANure Nutrient Evaluation Routine) is a decision support tool for quantifying manure (and other organic material) crop available nutrient supply. The user‐friendly design of an earlier version ofMANNERwas retained, but in response to user and stakeholder feedback, additional functionality was included to underpin new and revised nitrogen (N) transformation/loss modules (covering ammonia volatilization, nitrate leaching and nitrous oxide/di‐nitrogen emissions, and organic N mineralization) and also to estimate manure phosphorus (as P2O5), potassium (as K2O), sulphur (asSO3) and magnesium (as MgO) supply. Notably,MANNER‐NPKprovides N availability estimates for following crops through the mineralization of organic N. Validation of the crop available N supply estimates was undertaken by comparing predicted values with data from more than 200 field experimental measurements. For cattle, pig and poultry manures, there was good agreement (P < 0.001) between predicted and measured fertilizer N replacement values, indicating thatMANNER‐NPKprovides robust estimates of manure crop available N supply and N losses to the wider environment.
Treatment of BK virus‐associated hemorrhagic cystitis in pediatric hematopoietic stem cell transplant recipients with cidofovir: a single‐center experience
Authors: Kwon H.J. , Kang J.H. , Lee J.W. , Chung N.‐G. , Kim H.‐K. , Cho B.
Published: September 2013

Background

BK virus (BKV)‐associated hemorrhagic cystitis (BKV‐HC) is a severe complication after hematopoietic stem cell transplantation (HSCT). Cidofovir (CDV) has emerged as an effective agent for the treatment of BKV nephropathy, but its use for BKV‐HC in pediatric HSCT recipients has not yet been established as a standard therapy.

Patient and methods

We retrospectively investigated the efficacy and safety of CDV therapy for patients with BKV‐HC at a single institution and analyzed the clinical management outcomes.

Results

From April 2009 to July 2011, 12 patients developed BKV‐HC at a median of 37 days after transplant (range 15–59 days). The cumulative incidence was 9% and the median peak of the urine BKV load was 2.5 × 1010 copies/mL (range 1.4 × 109–1.2 × 1011 copies/mL). Eleven patients received intravenous CDV (5 mg/kg/dose, with probenecid), whereas 1 patient received CDV (5 mg/kg/dose, without probenecid) intravesically. The median duration of therapy was 25 days (range 9–73 days), and a median of 2 doses was given (range 1–4). A reduction of ≥1 log in the BKV load was found in 11 patients, while 1 patient did not have any significant change in BKV load. Clinical improvement was observed in all cases, and no HC‐related death was observed. CDV‐related toxicity occurred in 1 patient (8%) and spontaneously resolved.

Conclusions

CDV appears to be an effective and safe treatment for BKV‐HC in pediatric HSCT recipients, but prospective trials are warranted to support its use.
Concepts and Their Dynamics: A Quantum‐Theoretic Modeling of Human Thought
Authors: Aerts Diederik , Gabora Liane , Sozzo Sandro
Published: September 2013

We analyze different aspects of our quantum modeling approach of human concepts and, more specifically, focus on the quantum effects of contextuality, interference, entanglement, and emergence, illustrating how each of them makes its appearance in specific situations of the dynamics of human concepts and their combinations. We point out the relation of our approach, which is based on an ontology of a concept as an entity in a state changing under influence of a context, with the main traditional concept theories, that is, prototype theory, exemplar theory, and theory theory. We ponder about the question why quantum theory performs so well in its modeling of human concepts, and we shed light on this question by analyzing the role of complex amplitudes, showing how they allow to describe interference in the statistics of measurement outcomes, while in the traditional theories statistics of outcomes originates in classical probability weights, without the possibility of interference. The relevance of complex numbers, the appearance of entanglement, and the role of Fock space in explaining contextual emergence, all as unique features of the quantum modeling, are explicitly revealed in this article by analyzing human concepts and their dynamics.
A Reduced-Order Meshless Energy Model for the Vibrations of Mistuned Bladed Disks—Part II: Finite Element Benchmark Comparisons
Authors: Fang C. , McGee O. G. , El Aini Y.
Published: September 2013

This paper draws upon the theoretical basis and applicability of the three-dimensional (3-D) reduced-order spectral-based “meshless” energy technology presented in a companion paper (McGee et al., 2013, “A Reduced-Order Meshless Energy Model for the Vibrations of Mistuned Bladed Disks—Part I: Theoretical Basis,” ASME J. Turbomach., to be published) to predict free and forced responses of bladed disks comprised of randomly mistuned blades integrally attached to a flexible disk. The 3-D reduced-order spectral-based model employed is an alternative choice in the computational modeling landscape of bladed disks, such as conventionally-used finite element methods and component mode synthesis techniques, and even emerging element-free Hamiltonian–Galerkin, Petrov–Galerkin, boundary integral, and kernel-particle methods. This is because continuum-based modeling of a full disk annulus of mistuned blades is, at present, a steep task using these latter approaches for modal-type mistuning and/or rogue blade failure analysis. Hence, a considerably simplified and idealized bladed disk of 20 randomly mistuned blades mounted to a flexible disk was created and modeled not only to analyze its free and forced 3-D responses, but also to compare the predictive capability of the present reduced-order spectral-based “meshless” technology to general-purpose finite element procedures widely-used in industry practice. To benchmark future development of reduced-order technologies of turbomachinery mechanics analysts may use the present 3-D findings of the idealized 20-bladed disk as a new standard test model. Application of the 3-D reduced-order spectral-based “meshless” technology to an industry integrally-bladed rotor, having all of its blades modally mistuned, is also offered, where reasonably sufficient upper-bounds on the exact free and forced 3-D responses are predicted. These predictions expound new solutions of 3-D vibration effects of modal mistuning strength and pattern, interblade mechanical coupling, and localized modes on the free and forced response amplitudes.
Experimental Study of Surge Precursors in a High-Speed Multistage Compressor
Authors: Courtiade Nicolas , Ottavy Xavier
Published: September 2013

Pressure measurements using high frequency response sensors have been carried out on the third rotor of the 3.5-stage high speed compressor CREATE (rotation speed: 11,543 RPM, Rotor 1 tip speed: 313 m/s) over the complete characteristic line and during the surge transient. Precursors to the instabilities occurring near surge are observable at stable operating points. Just before surge, these precursors characterized as rotating disturbances grow in amplitude and provoke the onset a stall cell after a variable duration, which finally triggers surge. This paper presents a detailed analysis of the phenomena of rotating instabilities and surge transient and shows that it is possible to develop an antisurge active control system based on the early detection of the precursors.
Thermomechanical Stress Distributions in a Gas Turbine Blade Under the Effect of Cooling Flow Variations
Authors: Bolaina Candelario , Teloxa Julio , Varela Cesar , Sierra Fernando Z.
Published: September 2013

Thermomechanical stresses in gas turbine blades are investigated. Attention is focused on effects caused by varying the cooling airflow that runs through the blade interior, keeping constant a mainstream condition around the blade surface. Stress concentration was predicted numerically under engine real operating conditions. Temperature distributions in the metal blade surface produced by convective boundary conditions were linked with heat conduction within the blade using a conjugate solution. Results of stress concentration in the blade material for reduced cooling flow rate, blocked cooling ducts, and rotation rate were obtained. It is shown that temperature and stress distributions are a strong function of position in blade interior material and surface. Thermomechanical stress concentration was observed in the leading edge, with the endwall region affected by large stress concentration. Stress magnitude increments were found for combined cyclic thermal heating and sustained mechanical loads on specific planes of airfoil span for reduced cooling flow. Also, large stress gradients between leading and trailing regions of the blade were observed. The study reveals that blocking channels increase stresses in the central region of blade transversal cross section.
Turbine Blade Cooling System Optimization
Authors: Girardeau Julian , Pailhes Jérôme , Sebastian Patrick , Pardo Frédéric , Nadeau Jean-Pierre
Published: September 2013

Designing high performance cooling systems suitable for preserving the service lifetime of nozzle guide vanes of turboshaft engines leads to significant aerodynamic losses. These losses jeopardize the performance of the whole engine. In the same time, a low efficiency cooling system may affect the costs of maintenance repair and overhaul of the engine as component life decreases. Consequently, designing cooling systems of gas turbine vanes is related to a multiobjective design problem. In this paper, it is addressed by investigating the functioning of a blade and optimizing its design by means of an evolutionary algorithm. Systematic 3D CFD simulations are performed to solve the aero-thermal problem. Then, the initial multiobjective problem is solved by aggregating the multiple design objectives into one single relevant and balanced mono-objective function; two different types of mono-objective functions are proposed and compared. This paper also proposes to enhance available knowledge in the literature of cooling systems of gas turbine vanes by simulating the internal cooling system of the vane. From simulations thermal efficiency and aerodynamic losses are compared and their respective influences on the global performances of the whole engine are investigated. Finally, several optimal designs are proposed.
Aerothermal Impact of the Interaction Between Hub Leakage and Mainstream Flows in Highly-Loaded High Pressure Turbine Blades
Authors: Popović Ivan , Hodson Howard P.
Published: September 2013

This paper describes experimental and numerical investigations of a highly-loaded rotor blade with leakage (purge) flow injection through an upstream overlapping seal. The effects of both leakage mass flow rates and swirl have been studied to examine their effects on the aerothermal performance. As the leakage mass flow rate was increased, the loss generally increased. The increase in the losses was found to be nonlinear with the three distinct regimes of leakage-mainstream interaction being identified. The varying sensitivity of the losses to the leakage fraction was linked to the effects of the upstream potential field of the blade on a vortical structure originating from the outer part of the seal. This vortical structure affected the interaction between the leakage and mainstream flows as it grew to become the hub passage vortex. Very limited cooling was provided by the leakage flows. The coolant was mainly concentrated close to the suction surface in the front part of the rotor platform and on the blade suction surface in the path of the passage vortex. However, the regions benefiting from cooling were also characterized by higher values of the heat transfer coefficient. As a consequence, the net heat flux reduction was small, and the leakage injection was thus deemed thermally neutral.
Application of Nonaxisymmetric Endwall Contouring to Conventional and High-Lift Turbine Airfoils
Authors: Praisner T. J. , Allen-Bradley E. , Grover E. A. , Knezevici D. C. , Sjolander S. A.
Published: September 2013

Here, we report on the application of nonaxisymmetric endwall contouring to mitigate the endwall losses of one conventional and two high-lift low-pressure turbine airfoil designs. The design methodology presented combines a gradient-based optimization algorithm with a three-dimensional computational fluid dynamics (CFD) flow solver to systematically vary a free-form parameterization of the endwall. The ability of the CFD solver employed in this work to predict endwall loss modifications resulting from nonaxisymmetric contouring is demonstrated with previously published data. Based on the validated trend accuracy of the solver for predicting the effects of endwall contouring, the magnitude of predicted viscous losses forms the objective function for the endwall design methodology. This system has subsequently been employed to optimize contours for the conventional-lift Pack B and high-lift Pack D-F and Pack D-A low-pressure turbine airfoil designs. Comparisons between the predicted and measured loss benefits associated with the contouring for Pack D-F design are shown to be in reasonable agreement. Additionally, the predictions and data demonstrate that the Pack D-F endwall contour is effective at reducing losses primarily associated with the passage vortex. However, some deficiencies in predictive capabilities demonstrated here highlight the need for a better understanding of the physics of endwall loss-generation and improved predictive capabilities.
Dynamic Response of Battery Tabs Under Ultrasonic Welding
Authors: Kang Bongsu , Cai Wayne , Tan Chin-An
Published: September 2013

Ultrasonic metal welding (USMW) for battery tabs must be performed with 100% reliability in battery pack manufacturing as the failure of a single weld essentially results in a battery that is inoperative or cannot deliver the required power due to the electrical short caused by the failed weld. In ultrasonic metal welding processes, high-frequency ultrasonic energy is used to generate an oscillating shear force (sonotrode force) at the interface between a sonotrode and few metal sheets to produce solid-state bonds between the sheets clamped under a normal force. These forces, which influence the power needed to produce the weld and the weld quality, strongly depend on the mechanical and structural properties of the weld parts and fixtures in addition to various welding process parameters, such as weld frequencies and amplitudes. In this work, the effect of structural vibration of the battery tab on the required sonotrode force during ultrasonic welding is studied by applying a longitudinal vibration model for the battery tab. It is found that the sonotrode force is greatly influenced by the kinetic properties, quantified by the equivalent mass, equivalent stiffness, and equivalent viscous damping, of the battery tab and cell pouch interface. This study provides a fundamental understanding of battery tab dynamics during ultrasonic welding and its effect on weld quality, and thus provides a guideline for design and welding of battery tabs from tab dynamics point of view.
Investigation of Secondary Flow Behavior in a Radial Turbine Nozzle
Authors: Alexin Putra Mohammad , Joos Franz
Published: September 2013

Fundamental investigation of secondary flow phenomena in a radial turbine nozzle are presented. Laser two focus (L2F) measurements have been used for validation of numerical computational fluid dynamics (CFD) calculations. Having a good agreement by using the Reynolds stress turbulence model (RSM), the numerical results have been further used to analyze the structure of secondary vortices. Contour plots of the flow angle with typical isoline pattern, as well as the vorticity, have been evaluated. It is shown that the channel of the radial nozzle similar secondary vorticity systems generates as known from the axial turbine nozzles. The formation and the development of the horseshoe vortex and the corner vortex are discussed. The well known passage vortex of the axial turbines could not been found because of the small curvature of the streamlines. Instead of these, an additional single vortex can be observed, called the “inflow” vortex caused by the unsymmetrical flow into the radial cascade from the upstream scroll.
Toward the Expansion of Low-Pressure-Turbine Airfoil Design Space
Authors: Praisner T. J. , Grover E. A. , Knezevici D. C. , Popovic I. , Sjolander S. A. , Clark J. P. , Sondergaard R.
Published: September 2013

Future engine requirements, including high-altitude flight of unmanned air vehicles as well as an impetus to reduce engine cost and weight, are challenging the current state of the art in low-pressure-turbine airfoil design. These new requirements present low-Reynolds number challenges as well as the need for high-performance, high-lift design concepts. Here, we report on an effort to expand the relatively well established aerodynamic design space for low-pressure turbine airfoils through the application of recent developments in transition modeling to airfoil design. Analytical and experimental midspan performance data and predicted loadings are presented for four high-lift airfoil designs based on the Pack B velocity triangles. The new designs represent a systematic expansion of low-pressure turbine airfoil design space through the application of high-lift design concepts for front- and aft-loaded airfoils. All four designs performed as predicted across a range of operationally representative Reynolds numbers. Full-span loss data for the new high-lift designs reveal increased endwall losses, which, with the application of nonaxisymmetric endwall contouring, have been substantially reduced. Taken holistically, the results presented here demonstrate that accurate transition modeling provides a reliable method to develop optimized, very high-lift airfoil designs. However, further improvements in endwall-loss mitigation technologies are required to enable the implementation of the very high-lift technology presented here in engine systems.
Improving Turbine Stage Efficiency and Sealing Effectiveness Through Modifications of the Rim Seal Geometry
Authors: Popovíc Ivan , Hodson Howard P.
Published: September 2013

This paper presents an investigation of a range of engine realistic rim seals starting from a simple axial seal to different types of overlapping seals. The experiments were performed in a large-scale linear cascade equipped with a secondary air system capable of varying independently both the mass fraction as well as the swirl velocity of the leakage air. The experimental results were also complemented by computationally fluid dynamics (CFD) to provide better insight in the flow physics. It has been found that the key feature of the rim seals that affect their impact on overall loss generation and their ability to provide good sealing effectiveness was the location and the size of the recirculation zones within the rim seal. The requirements for good sealing and reduced spoiling effects on the main gaspath flow often led to contradictory designs. In general, the recirculation zones were found to improve sealing by reducing the effect of the pitchwise (circumferential) variation in the pressure distribution due to the blade's potential field, and thus reduce ingestion. However, at the same time the recirculation zones tend to increase the loss generation. The best compromise was found when the outer part of the seal and its interface with the rotor platform was as smooth as possible to minimize the spoiling losses, while the recirculation zones were confined to the inner part of the seal to maintain acceptable levels of sealing effectiveness. A new rim seal design, which utilizes the best attributes of the above mentioned designs was developed. Linear cascade tests showed the losses due to the leakage-mainstream interaction were reduced by 33% compared to the datum seal design. Further validation was performed by examining the new configuration using unsteady full-stage calculations under engine realistic conditions. These calculations suggest an improvement of nearly 0.2% in the stage efficiency.
Tool Wear in Cutting Operations: Experimental Analysis and Analytical Models
Authors: Attanasio A. , Ceretti E. , Giardini C. , Cappellini C.
Published: September 2013

The possibility of predicting the amount of the tool wear in machining processes is an interesting topic for industries, since tool wear affects surface integrity of the final parts and tool life is strictly connected with substitution policy and production costs. The definition of models able to correctly forecast the tool wear development is an important topic in the research field. For this reason in the present work, a comparison between response surface methodology (RSM) and artificial neural networks (ANNs) fitting techniques in tool wear forecasting was performed. For developing these predictive models, experimental values of tool wear, obtained by longitudinal turning operations with variable cutting parameters, were collected. Once selected, the best configuration of the two previously mentioned techniques, the resultant errors with respect to experimental data were estimated and then compared. The results showed that the developed models are able to predict the amount of wear. The comparison demonstrated that ANNs give better approximation than RSM in the prediction of the amount of the flank wear (VB) and of the crater wear (KT) depth. The obtained results are interesting not only from a scientific point of view but also for industries. In fact, it should be possible to implement the best model into a production manager software in order to correctly define the tool change during the lot production.
Analysis of Residual and Operational Thermal Stresses in a Planar SOFC
Authors: Severson Henning , Assadi Mohsen
Published: September 2013

A structural model has been developed for analysis of residual stresses for anode- and electrolyte-supported planar solid oxide fuel cells (SOFC). This model was also used for analysis of thermally induced stresses during operation for three different case studies with the electrolyte-supported geometry. Temperature distribution in the solid parts of the cell was modeled by means of an in-house electrochemical model, and the results were exported to the structural model. In the case studies, the impact of air and fuel inlet temperatures, steam reforming, and operation voltages on thermal stresses were studied. Weibull statistics were used for the prediction of failure probabilities and design considerations. Base case geometry for the electrolyte-supported cell was 50, 150, and 50 μm for anode, electrolyte, and cathode thicknesses, respectively, and for the anode-supported cell 1000, 20, and 50 μm, respectively. Analysis of residual stresses showed that, compared with the anode-supported cell, the electrolyte-supported cell experienced considerably higher stress levels in the anode and cathode due to the thick electrolyte, while the stress levels in the electrolyte were lower. For the anode-supported cell, maximum stress levels were 57, −12, and −678 MPa in the anode, cathode, and electrolyte, respectively, with negative values indicating compressive and positive values, tensile stresses. For the electrolyte-supported geometry, the corresponding levels were 282, 100, and −308 MPa, respectively. With a failure probability of 1E-6 and an electrolyte thickness of 10 μm, the minimum allowable anode thickness was estimated to be 1000 μm. For an electrolyte-supported cell, optimal thicknesses of electrolyte and anode were considered to be 100 and 100 μm, respectively, while the thickness of the cathode showed low impact. During operation, the stress levels were reduced considerably, since high operating temperatures reduce the temperature difference to the sintering temperature (1250 °C). Concerning the presence of methane in the fuel and the effect of steam reforming, small amounts of methane—as low as 10% of molar mass—were found to induce a cooling effect with correspondingly high gradients. With 45% methane in the fuel, the tensile stress level in the anode was about 130 MPa; the impact of thermal gradients was considered to be 40 MPa and the cooling effect also 40 MPa.
Electrical characterization of 60Co gamma radiation-exposed InAlN/GaN high electron mobility transistors
Authors: Kim Hong-Yeol , Kim Jihyun , Liu Lu , Lo Chien-Fong , Ren Fan , Pearton Stephen J.
Published: September 2013

In0.17Al0.83N/GaN high electron mobility transistors (HEMTs) were cumulatively subjected to 60Co gamma-ray irradiation doses up to 500 Mrad. Source–drain current–voltage characteristics (IDS-VDS) showed little change after lower dose gamma-ray irradiations (<200 Mrad). However, the electrical properties were significantly degraded after 500 Mrad irradiations, indicating that the radiation-induced damage near the active region of the devices was severe. The saturation current level at VGS = 0 V was degraded by 48% after 500 Mrad irradiation. The effective carrier removal rate was not linear with dose, but was 0.54 × 1010 cm−2 Mrad−1 in the range from 200 to 500 Mrad. The cumulative gamma-ray irradiation of In0.17Al0.83N/GaN HEMTs caused much larger reductions in drain–source current compared to AlGaN/GaN devices exposed under the same conditions.
Perceived listening effort for a tonal task with contralateral competing signals
Authors: Bologna William J. , Chatterjee Monita , Dubno Judy R.
Published: September 2013

Perceived listening effort was assessed for a monaural irregular-rhythm detection task while competing signals were presented to the contralateral ear. When speech was the competing signal, listeners reported greater listening effort compared to either contralateral steady-state noise or no competing signal. Behavioral thresholds for irregular-rhythm detection were unaffected by competing speech, indicating that listeners compensated for this competing signal with effortful listening. These results suggest that perceived listening effort may be associated with suppression of task-irrelevant information, even for conditions where informational masking and competition for linguistic processing resources would not be expected.
Circulating Tumor Cells
Authors: Plaks Vicki , Koopman Charlotte D. , Werb Zena
Published: September 2013

Much remains to be learned about CTCs and their clinical potential as biomarkers and therapeutic targets.
Channelized Ice Melting in the Ocean Boundary Layer Beneath Pine Island Glacier, Antarctica
Authors: Stanton T. P. , Shaw W. J. , Truffer M. , Corr H. F. J. , Peters L. E. , Riverman K. L. , Bindschadler R. , Holland D. M. , Anandakrishnan S.
Published: September 2013

Active Ice

How, exactly, does warm ocean water erode an ice shelf? In a field study of an ice shelf at Pine Island, Antarctica,

Stanton
et al.

(p.
1236
) collected data from radar, seismic surveys, and oceanographic sensors inserted in holes bored through the ice shelf. The results show that localized, intensive melting occurs in a complex network of discreet channels that are formed on the underside of the shelf. This pattern of melting may limit the absolute rate of ice-shelf mass loss.
Cytoplasmic LPS Activates Caspase-11: Implications in TLR4-Independent Endotoxic Shock
Authors: Hagar Jon A. , Powell Daniel A. , Aachoui Youssef , Ernst Robert K. , Miao Edward A.
Published: September 2013

Move Over, TLR4

The innate immune system senses bacterial lipopolysaccharide (LPS) through Toll-like receptor 4 (TLR4) (see the Perspective by

Kagan

). However,

Kayagaki
et al.

(p
1246
, published online 25 July) and

Hagar
et al.

(p.
1250
) report that the hexa-acyl lipid A component of LPS from Gramnegative bacteria is able to access the cytoplasm and activate caspase-11 to signal immune responses independently of TLR4. Mice that lack caspase-11 are resistant to LPS-induced lethality, even in the presence of TLR4.
Diversity Among Memory B Cells: Origin, Consequences, and Utility
Authors: Tarlinton David , Good-Jacobson Kim
Published: September 2013

Immunological memory is the residuum of a successful immune response that in the B cell lineage comprises long-lived plasma cells and long-lived memory B cells. It is apparent that distinct classes of memory B cells exist, distinguishable by, among other things, immunoglobulin isotype, location, and passage through the germinal center. Some of this variation is due to the nature of the antigen, and some appears to be inherent to the process of forming memory. Here, we consider the heterogeneity in development and phenotype of memory B cells and whether particular functions are partitioned into distinct subsets. We consider also how understanding the details of generating memory may provide opportunities to develop better, functionally targeted vaccines.
Portraits from a Collision
George Catlin
American Indian Portraits

Stephanie Pratt and Joan Carpenter Troccoli, curators

National Portrait Gallery, London, in association with the Smithsonian American Art Museum. Through 23 June 2013. www.npg.org.uk/whatson/george-catlin-americanindian-portraits/exhibition.php
George Catlin
American Indian Portraits

by Stephanie Pratt and Joan Carpenter Troccoli

National Portrait Gallery, London. 2013. 190 pp. £25. ISBN 9781855144576
Authors: Ash Caroline
Published: September 2013

Through his portraits, Catlin sought to document Native Americans and their threatened ways of life in the 1830s.
Organotextile Catalysis
Authors: Lee Ji-Woong , Mayer-Gall Thomas , Opwis Klaus , Song Choong Eui , Gutmann Jochen Stefan , List Benjamin
Published: September 2013

Catalytic Parachute

Small organic molecules have emerged as catalysts as versatile as transition metal complexes. However, industrial application of such organocatalysts has been hampered by technical challenges. Now

Lee
et al.

(p.
1225
) have succeeded in tethering a diverse set of high-performance organocatalysts to nylon fabric through ultraviolet photochemistry, making them easy to isolate and reuse.
A Flawed Diagnosis
The Body Economic
Why Austerity Kills: Recessions, Budget Battles, and the Politics of Life and Death

by David Stuckler and Sanjay Basu

Basic Books, New York, 2013. 238 pp. $25.99. ISBN 9780465063987. Allen Lane, London, £20. ISBN 9781846147838.
Authors: Tapia Granados José A.
Published: September 2013

Stuckler and Basu argue that the harsh austerity measures and cutting of social programs adopted in response to the recent financial crisis have exacerbated public health problems and cost thousands of lives.
Sources of Antimicrobial Resistance
Authors: Woolhouse Mark E. J. , Ward Melissa J.
Published: September 2013

Genomic data help to elucidate the role of food animals in the spread of antimicrobial resistance in humans.

[Also see Report by

Mather
et al.

]
Toward Lighter, Stiffer Materials
Authors: Schaedler Tobias A. , Jacobsen Alan J. , Carter Wiliam B.
Published: September 2013

Lightweight cellular (porous) materials are assembled from prefabricated building blocks.

[Also see Report by
Cheung and Gershenfeld
]
Translating Antibody Insights
Authors: Gerberding Julie Louise
Published: September 2013

Viruses that defy host immune responses and persist or recur take a huge toll on global human health. Many of these, including HIV-1, influenza viruses, and several flaviviruses (such as dengue, hepatitis C, and West Nile virus) rapidly proliferate, frequently mutate, and evolve highly variable surface structures. The effectiveness of such immune escape mechanisms has thwarted multiple attempts to create long-lasting and broadly protective vaccines.
Bound for Glory
Authors: Cohen Jon
Published: September 2013

The discovery of antibodies that foil almost every HIV variant has transformed the AIDS vaccine search.
Genome Sequence of the Melanin-Producing Extremophile Aeromonas salmonicida subsp.
pectinolytica
Strain 34mel
T
Authors: Pavan M. Elisa , Pavan Esteban E. , López Nancy I. , Levin Laura , Pettinari M. Julia
Published: September 2013

The genome of
Aeromonas salmonicida
subsp.
pectinolytica
strain 34mel
T
, isolated from a heavily polluted river, contains several genomic islands and putative virulence genes. The identification of genes involved in resistance to different kinds of stress sheds light on the mechanisms used by this strain to thrive in an extreme environment.
Draft Genome Sequence of Sphingobium quisquiliarum Strain P25
T
, a Novel Hexachlorocyclohexane (HCH)-Degrading Bacterium Isolated from an HCH Dumpsite
Authors: Kumar Singh Amit , Sangwan Naseer , Sharma Anukriti , Gupta Vipin , Khurana J. P. , Lal Rup
Published: September 2013

Here, we report the draft genome sequence (4.2 Mb) of
Sphingobium quisquiliarum
strain P25
T
, a natural
lin
(genes involved in degradation of hexachlorocyclohexane [HCH] isomers) variant genotype, isolated from a heavily contaminated (450 mg HCH/g of soil) HCH dumpsite.
Complete Genomic Sequence of “
Thermofilum adornatus
” Strain 1910b
T
, a Hyperthermophilic Anaerobic Organotrophic Crenarchaeon
Authors: Dominova I. N. , Kublanov I. V. , Podosokorskaya O. A. , Derbikova K. S. , Patrushev M. V. , Toshchakov S. V.
Published: September 2013

The complete genomic sequence of a novel hyperthermophilic crenarchaeon, strain 1910b
T
, was determined. The genome comprises a 1,750,259-bp circular chromosome containing single copies of 3 rRNA genes, 43 tRNA genes, and 1,896 protein-coding sequences.
In silico
genome-genome hybridization suggests the proposal of a novel species, “
Thermofilum adornatus
” strain 1910b
T
.
Performance of the Parent Report of Children's Abilities–Revised (PARCA-R) versus the Bayley Scales of Infant Development III
Authors: Martin Andrew J , Darlow Brian A , Salt Alison , Hague Wendy , Sebastian Lucille , McNeill Nicki , Tarnow-Mordi William
Published: September 2013

Background

The Parent Report of Children’s Abilities-Revised (PARCA-R) assesses cognitive and language development at 24 months. It was validated against the Mental Development Index of the Bayley Scales of Infant Development II (BSID II), but this has now been superseded by BSID III.

Objective

To compare the PARCA-R against the BSID III.

Methods

PARCA-R and BSID III assessments scheduled at 24 months of age (corrected for prematurity) were completed in 204 infants with suspected or proven neonatal sepsis in the International Neonatal Immunotherapy Study. Associations between the scales were measured and the predictive accuracy of the PARCA-R for moderate cognitive delay and moderate language delay was assessed using Receiver Operating Characteristic (ROC) analysis.

Results

Median birthweight was 911 g, median gestational age at birth was 27 weeks and 100 (49.0%) were girls. 4.4% and 8.4% met standard BSID III criteria for cognitive delay and language delay, respectively. These rates increased to 19.6% and 12.6% when an independent sample of normal term infants were used as the reference group suggesting standard BSID III reference norms may tend to underestimate delay. The Spearman correlation between PARCA-R and BSID scales were 0.43 for cognition and 0.71 for language. The PARCA-R successfully predicted cases of cognitive delay and language delay with the area under the ROC curves ranging from 0.83 to 0.97 depending on reference norms used.

Conclusions

The results support the PARCA-R as a practical tool for the identification of appreciable cognitive and language delay at 24 months among critically ill premature and extremely low birthweight neonates.
Toxic epitheliopathy from a single application of preservative free oxybuprocaine (0.4%) in a patient with Sjogren's syndrome
Authors: Ansari Humaira , Weinberg Laurence , Spencer Narelle
Published: September 2013

Topical ocular anaesthetic agents are frequently used for ophthalmic diagnosis and surgery. While corneal complications following long-term use or misuse of local anaesthetic solutions have been described, toxic epitheliopathy after a single application of six drops of preservative free oxybuprocaine is rare. In order to increase the awareness of this ocular complication, we report such a case in a patient with Sjogren's syndrome who presented for elective cataract surgery. We outline the mechanisms proposed to explain the ocular toxic effects of oxybuprocaine and discuss the management principles in preventing this complication in the context of Sjogren's syndrome.
Atypical blood and bone marrow lymphocytes in ALK-positive anaplastic T-cell lymphoma: important lessons
Authors: Mahdi A J , Elmusharaf N , Osman H , Thompson I
Published: September 2013

A 42-year-old man presented with a short history of fever, significant weight loss and bilateral neck swelling. A CT scan revealed widespread lymphadenopathy and hepatosplenomegaly. Lymph node morphology and immunohistochemistry confirmed a diagnosis of anaplastic lymphoma kinase (ALK)-positive anaplastic T-cell non-Hodgkin's lymphoma. Both the peripheral blood (PB) and bone marrow (BM) revealed atypical lymphocytes with cleaved nuclei, vacuolation and granulation, suggestive of disease involvement at both sites. However, BM and PB immunophenotyping and immunohistochemistry did not reveal typical markers (ALK and CD30) at either site. All features resolved with a short remission after conventional chemotherapy. Despite salvage chemotherapy and an autologous stem cell transplant, a relapse of the PB and BM features with stable radiological findings was noted. Rapid decline followed with pancytopenia resulting in death 12 months after the initial diagnosis.