bluuebunny/crossref_metadata_2025 huggingface dataset:
Vulnerability of pastoral farming in Hawke's Bay to future climate change: Development of a pre‐screening (bottom‐up) methodology
Authors: Fowler Anthony M. , Aiken Simon , Maree Kim
Published: August 2013

Although future climate change will significantly affect New Zealand's climate, how regional climates will be changed remains highly uncertain. As a consequence, pre‐screening sensitivity analysis is recommended for climate‐sensitive activities. A ‘bottom‐up’ approach intended to serve this purpose in the context of non‐irrigated pasture is developed and demonstrated in the Hawke's Bay context. This is achieved using a simple daily water balance model to simulate near‐surface hydrological processes and empirical relationships between transpiration and pasture dry matter production. The Hawke's Bay case study indicates that the methodology has merit and is worthwhile pursuing nationally (with refinements).
Spatial dimensions of New Zealand's environmental management
Authors: McNeill Jeffrey , Cheyne Christine , Summers Rachel
Published: August 2013

New Zealand's regional council boundaries drawn as part of the 1989 local government reforms privilege integrated catchment management. This privilege is now challenged by calls to both fragment and amalgamate councils and centralise decision‐making but with little analytic assessment of the spatial differentiation to support them. The spatial underpinnings of these calls were explored using a case study that assessed the spatial dimensions of environment management. Analysis of the Land Environments and River Environment Classification databases and councils' planning documents highlights challenges local governments face in applying integrated natural resource management within single purpose jurisdictions and implications for wider sustainable development policy.
Global divides: Deconstructing the way we see the world should not be left to senior geography
Authors: Tallon Rachel
Published: August 2013

Terms such as ‘Third World/First World’, ‘Developing/Developed’ are still in common usage despite many commentators and educators signalling that they are inadequate. Using empirical evidence from research in New Zealand, this paper discusses how these dividing terms may be under stress among young people who seek new ways of learning about places and people. In conceptualising the South Pacific, terms like ‘developing world’ may be challenged by young people. Debating these terms at all levels of education is important and should not merely be left to tertiary levels.
Sensitivity and specificity of the Streptococcus pneumoniae urinary antigen test for unconcentrated urine from adult patients with pneumonia: A meta‐analysis
Authors: Horita Nobuyuki , Miyazawa Naoki , Kojima Ryota , Kimura Naoko , Inoue Miyo , Ishigatsubo Yoshiaki , Kaneko Takeshi
Published: August 2013

Studies on the sensitivity and specificity of the Binax Now Streptococcus pneumonia urinary antigen test (index test) show considerable variance of results. Those written in English provided sufficient original data to evaluate the sensitivity and specificity of the index test using unconcentrated urine to identify S. pneumoniae infection in adults with pneumonia. Reference tests were conducted with at least one culture and/or smear. We estimated sensitivity and two specificities. One was the specificity evaluated using only patients with pneumonia of identified other aetiologies (‘specificity (other)’). The other was the specificity evaluated based on both patients with pneumonia of unknown aetiology and those with pneumonia of other aetiologies (‘specificity (unknown and other)’) using a fixed model for meta‐analysis. We found 10 articles involving 2315 patients. The analysis of 10 studies involving 399 patients yielded a pooled sensitivity of 0.75 (95% confidence interval: 0.71–0.79) without heterogeneity or publication bias. The analysis of six studies involving 258 patients yielded a pooled specificity (other) of 0.95 (95% confidence interval: 0.92–0.98) without no heterogeneity or publication bias. We attempted to conduct a meta‐analysis with the 10 studies involving 1916 patients to estimate specificity (unknown and other), but it remained unclear due to moderate heterogeneity and possible publication bias. In our meta‐analysis, sensitivity of the index test was moderate and specificity (other) was high; however, the specificity (unknown and other) remained unclear.
Godless Jews and Secular Christians: A Commentary on Gil Anidjar's “Jesus and Monotheism”
Authors: Zakin Emily
Published: August 2013

Responding to Gil Anidjar's “Jesus and Monotheism” and its posing of the “Christian Question,” in this paper I return to Freud's Moses and Monotheism and its narrative of Jewish self‐division. In highlighting the retroactive formation of identity, I note both its temporal dimension and the force of exclusivity it generates. This reading suggests a contrast between such theo‐political communities, with their legacies of affiliation, and Christian self‐absolution (the refusal of constitutive self‐division) with its image of a new man. I take a brief detour through Marx and Schmitt to examine the founding structures of secular modernity and the entanglement of liberalism with Christianity. Pursuing a hint offered by Anidjar that Christianity is not quite a tradition, I conclude that for Freud, the “Christian question” emerges as a kind of enigma: the dream of a community divorced from human modes of transmission, unbound by legacies of filiation to the past, and replacing the collective memory of a people with the end of human collectivity.
Drive between Brain and Subject: An Immanent Critique of Lacanian Neuropsychoanalysis
Authors: Johnston Adrian
Published: August 2013

Despite Jacques Lacan's somewhat deserved reputation as an adamant antinaturalist, his teachings, when read carefully to the letter, should not be construed as categorically hostile to any and every possible interfacing of psychoanalysis and biology. In recent years, several authors, including myself, have begun exploring the implications of reinterpreting Lacan's corpus on the basis of questions concerning naturalism, materialism, realism, and the position of analysis with respect to the sciences of today. Herein, I focus primarily on the efforts of analyst François Ansermet and neuroscientist Pierre Magistretti to forge a specifically Lacanian variant of neuropsychoanalysis (as distinct from Anglo‐American variants). Taking up Ansermet and Magistretti's interlinked theories of drive (Trieb) and autonomous subjectivity, I develop an immanent critique of their project. Doing so in a manner that is intended to acknowledge and preserve this neuropsychoanalytic duo's significant insights and contributions, I seek to bring into sharper relief the exact set of necessary, as well as sufficient, conditions for what Ansermet, Magistretti, and I all are commonly pursuing: an account of the genesis of denaturalized subjects out of embodied libidinal economies, itself situated within the framework of a nonreductive, quasi‐naturalist materialism synthesizing resources drawn from psychoanalysis, neurobiology, and philosophy.
Jesus and Monotheism
Authors: Anidjar Gil
Published: August 2013

From Oedipus to Moses and beyond, Freud's last book has been read with singular obstinacy as addressing a Jewish (or anti‐Semitic) question, or as renewing a religious (or antireligious) agenda. Between Athens and Jerusalem, from Judaism to a more general “monotheistic religion,” and from Oedipus (the son) to Moses (the father), scholars have explored or refuted numerous traces the primal murder left and many among the founding fathers, the substitutes to which it gave rise. Yet it is easy to see that the reception of Freud has been fairly consistent in skipping over not so much the general religious (monotheistic, or even civilizational and universal) import of Freud's work, but rather the exorbitant centrality in it of Jesus Christ, the acutely singular question of Christianity and its founder.
When Mental States Matter, When They Don't, and What That Means for Morality
Authors: Young Liane , Tsoi Lily
Published: August 2013

Research has shown that moral judgments depend on the capacity to engage in mental state reasoning. In this article, we will first review behavioral and neural evidence for the role of mental states (e.g., people's beliefs, desires, intentions) in judgments of right and wrong. Second, we will consider cases where mental states appear at first to matter less (i.e., when people assign moral blame for accidents and when explicit information about mental states is missing). Third, we will consider cases where mental states, in fact, matter less, specifically, in cases of “purity” violations (e.g., committing incest, consuming taboo foods). We will discuss how and why mental states do not matter equivalently across the multi‐dimensional space of morality. In the fourth section of this article, we will elaborate on the possibility that norms against harmful actions and norms against “impure” actions serve distinct functions – for regulating interpersonal interactions (i.e., harm) versus for protecting the self (i.e., purity). In the fifth and final section, we will speculate on possible differences in how we represent and reason about other people's mental states versus our own beliefs and intentions. In addressing these issues, we aim to provide insight into the complex structure and distinct functions of mental state reasoning and moral cognition. We conclude that mental state reasoning allows us to make sense of other moral agents in order to understand their past actions, to predict their future behavior, and to evaluate them as potential friends or foes.
Obsessional Whiteness and the Unpaid Debt of Apartheid
Authors: Truscott Ross
Published: August 2013

This paper considers post‐apartheid South African Whiteness from a psychoanalytic perspective. A point of focus is Samantha Vice's controversial and much debated recent article on the ethical quandaries of post‐apartheid White privilege, “How Do I Live in this Strange Place?”, which is read alongside J.M. Coetzee's essay, “The Mind of Apartheid”, written in the early 1990s on the brink of South Africa's transition. Coetzee used a Freudian framework of obsessional neurosis to highlight what he saw as the libidinal economy of apartheid, suggesting that apartheid policies were not only or even primarily aimed at consolidating White material privilege; they were, rather, in Coetzee's view, a set of measures designed to preserve the purity of the White social body from contamination. What the juxtaposition of Coetzee and Vice suggests is that, while the stain of South African Whiteness has shifted or been displaced, post‐apartheid White antiracism, exemplified in the critical discourse Vice elaborates, remains as obsessional, as concerned with keeping the White social body clean, pure, as apartheid thinking. The paper then concludes by considering the usefulness, but also, crucially, the limits of psychoanalysis as a critical frame for interrogating the continuities between apartheid and the new South Africa.
Capitalising on Spatiality in European Transport Corridors
Authors: Witte Patrick , Van Oort Frank , Wiegmans Bart , Spit Tejo
Published: August 2013

After half a century of corridor development in Europe, the corridor concept is well‐established in the academic discourse on transportation. Transport corridors have also been common practice in European transport policy since the creation of a borderless Europe in the 1990s. What is largely lacking in present‐day research on European transport corridors is a consideration of a sector‐transcendent and comprehensive spatial approach. We argue that adopting such an approach is beneficial to a valued analysis of European transport corridors, especially in the light of EU cohesion policy, agglomeration effects and place‐based development. Also, negative external effects of persisting bottlenecks on welfare and quality of life in transport corridors should be better assessed and contextualised. This paper therefore suggests that policy can and should capitalise more on spatiality in corridors.
Linking Time Geography and Activity Theory to Support the Activities of Mobile Information Seekers
Authors: Crease Paul , Reichenbacher Tumasch
Published: August 2013

Mobile geographic information seeking systems are often employed to support spatial activities in an unfamiliar geographic environment. However, current systems are unable to incorporate the spatio‐temporal constraints of these activities in order to support this information seeking. This article describes a methodology addressing the nature of these spatio‐temporal activities that has the potential to contribute solutions to this problem. A key element of this approach is the awareness that both the planning and acting phases must be considered in supporting such activities. This means the development of plans that can be amended ad‐hoc, whilst still adhering to the spatio‐temporal constraints of the activity. The results of such an approach are the ability for a more descriptive representation of a spatio‐temporal activity, which can then be used to support spatio‐temporal accessibility analyses and disclose geographic information objects that are no longer accessible to the mobile information seeker. The introduction of these spatio‐temporal constraints also allows the mobile information seeker to build up an itinerary that adheres to the given spatio‐temporal constraints of the activity.
Dress Rehearsals, Previews, and Encores: A New Account of Mental Representation
Authors: Salay Nancy
Published: August 2013

One of the central debates in cognitive science is the dispute over the role of representation in cognition: on computational/representational accounts, representations are theoretically central; on dynamic systems approaches in which cognition is investigated as a particular sort of physical process, representations play either no role, or, at best, a derivative one. But these two perspectives lead to a deeply unsatisfying theoretical divide: accounts situated in the representational camp are plagued by the inscrutable problem of intentionality, while those hedging towards anti‐representationalism seem incapable of saying anything theoretically interesting about high‐level cognition. This unhelpful polarization is due in part, at least, to a muddy debate; while some take representationalism to be a commitment to the necessity of conceptual representations for cognition, representations the having of which require certain conceptual capacities, others do not. Recently, there has been a surge of work on non‐conceptual representation. This article aims to add to this movement by suggesting a particular cognitive mechanism for non‐conceptual representations, one that plays a pivotal role in making conceptual representations possible. One of the central consequences of this new view of representation is the possibility of a non‐question‐begging naturalistic account of intentionality.
Decreasing phosphodiesterase 5A activity contributes to platelet cGMP accumulation during storage of apheresis‐derived platelet concentrates
Authors: Kobsar Anna , Putz Evelyn , Yilmaz Pinar , Weinig Elke , Boeck Markus , Koessler Juergen
Published: August 2013

Background

Platelet storage lesion (PSL) considerably decreases the quality of platelets (PLTs) in concentrates characterized by a loss of signaling responses to agonists and impaired PLT activation, secretion, and aggregation. To understand the role of inhibitory signaling pathways in the mechanism of PSL, the basal state of the cyclic nucleotide (CN)‐dependent signaling systems in stored PLTs was investigated.

Study Design and Methods

Whole blood samples (WB) and apheresis‐derived PLT concentrates (APCs) were obtained from healthy volunteers. Washed PLTs were prepared from WB on Day 0 and from APCs on Days 0, 2, and 5. The basal phosphorylation of the vasodilator‐stimulated phosphoprotein (VASP) and phosphodiesterase 5A (PDE5A) levels were quantified by Western blot. CN and PDE5A activity were measured by enzyme‐linked immunoassay kits. Fibrinogen binding and aggregation were measured in PLT‐rich plasma of WB or APC samples. Unpaired t test was used for statistical analysis.

Results

Basal VASP phosphorylation levels were comparable in WB and APCs on Day 0. VASP phosphorylation increased significantly during storage of APCs, more pronounced at Ser239 than at Ser157. Similarly, intracellular cGMP, but not cAMP, concentration continuously increased in stored PLTs, whereas PDE5A levels and activity significantly decreased accompanied by diminished thrombin receptor activator peptide 6–induced fibrinogen binding and aggregation.

Conclusion

Storage of APCs leads to intracellular cGMP accumulation that could be caused by degradation of PDE5A. Enhanced cGMP level supports subsequent cGMP‐dependent protein kinase–mediated increase of VASP phosphorylation resulting in reduced fibrinogen binding and aggregation.
Conjunctival lymphoma: immunophenotype and outcome in five dogs and three cats
Authors: McCowan Christina , Malcolm Julia , Hurn Simon , O'Reilly Anu , Hardman Chloe , Stanley Robin
Published: August 2013

Conjunctival lymphoma is well documented in the medical literature, but veterinary reports are few. We report five cases of canine lymphoma, and three of feline in which the presenting sign was conjunctival involvement. All animals were in apparently good health at the time of presentation, and attended the referring clinic because of conjunctival disease. One dog showed generalized lymphadenopathy at presentation, although the ocular lesion was the reason for consultation, but all other patients were well with no detectable disease beyond the eye. All cats were presented for their ocular disease. All dogs were confirmed to have T‐cell tumors, although the histological appearance of these was variable. In contrast, all cats had B‐cell tumors. Referring clinicians and owners were contacted for follow‐up information. Three dogs had been euthanased within 6 months of diagnosis for deterioration of general health. The remaining two were alive and showed no signs of systemic disease. Two cats had good survival following diagnosis, the other died of lesions that may not be related.
2013 Timoshenko Medal Award Paper—Completion and Closure on Failure Criteria for Unidirectional Fiber Composite Materials
Authors: Christensen Richard M.
Published: August 2013

Building upon previous work, the failure criterion for unidirectional fiber composite materials is examined using a sensitivity analysis as applied to its transverse, matrix controlled failure properties. A new and general relationship is found between these three properties thereby reducing the total number of independent properties needed to calibrate the theory to five. This completes and closes the development of failure criteria for unidirectional fiber composites by the polynomial invariants method. A broad but detailed evaluation of the resulting failure criteria is given. Future applications for these new failure criteria are discussed.
Universal three-dimensional nanofabrication for hard materials
Authors: Yamazaki Kenji , Yamaguchi Hiroshi
Published: August 2013

Three-dimensional (3D) nanofabrication technologies are entering new phases in advanced application fields, such as nanorobotics, metamaterials, and nanomechanical systems. In particular, the ability to arbitrarily create 3D nanostructures in hard materials like semiconductors and metals with nanometer-scale resolution will accelerate innovation in these fields, although a versatile technology applicable to various materials has not yet been established. The authors have devised a flexible 3D nanofabrication technique that is applicable to any material in principle. It uses 3D electron beam (EB) writing of arbitrary patterns followed by 3D ion etching, where the EB and ions fly in directions vertical and parallel to the substrate surface. Characteristics of the etching angle were investigated, and large angled etching of 88° was achieved. 3D nanostructures fabricated in single-crystal Si demonstrate that this technique has high resolution, high fabrication speed, and a large degree of freedom in the 3D shapes and dimensions that can be realized.
High amplitude nonlinear acoustic wave driven flow fields in cylindrical and conical resonators
Authors: Antao Dion Savio , Farouk Bakhtier
Published: August 2013

A high fidelity computational fluid dynamic model is used to simulate the flow, pressure, and density fields generated in a cylindrical and a conical resonator by a vibrating end wall/piston producing high-amplitude standing waves. The waves in the conical resonator are found to be shock-less and can generate peak acoustic overpressures that exceed the initial undisturbed pressure by two to three times. A cylindrical (consonant) acoustic resonator has limitations to the output response observed at one end when the opposite end is acoustically excited. In the conical geometry (dissonant acoustic resonator) the linear acoustic input is converted to high energy un-shocked nonlinear acoustic output. The model is validated using past numerical results of standing waves in cylindrical resonators. The nonlinear nature of the harmonic response in the conical resonator system is further investigated for two different working fluids (carbon dioxide and argon) operating at various values of piston amplitude. The high amplitude nonlinear oscillations observed in the conical resonator can potentially enhance the performance of pulse tube thermoacoustic refrigerators and these conical resonators can be used as efficient mixers.
Binaural speech intelligibility in rooms with variations in spatial location of sources and modulation depth of noise interferers
Authors: Collin Benjamin , Lavandier Mathieu
Published: August 2013

Four experiments investigated the effects on speech intelligibility of reverberation, sound source locations, and amplitude modulation of the interferers. Speech reception thresholds (SRTs) were measured using headphones and stimuli that simulated real-room listening, considering one or two interferers which were stationary or speech-modulated noises. In experiment 1, SRTs for modulated noises showed little variation with increasing interferer reverberation. Reverberation might have increased masking by filling in the modulated noise gaps, but simultaneously changed the noise spectra making them less effective maskers. In experiment 2, SRTs were lower when measured using a unique one-voice modulated interferer rather than a different interferer for each target sentence, suggesting that listeners could take advantage of the predictability of the interferer gaps. In experiment 3, increasing speech reverberation did not significantly affect the difference of SRTs measured with stationary and modulated noises, indicating that the ability to exploit noise modulations was still useful for temporally smeared speech. In experiment 4, spatial unmasking remained constant when applying modulations to the interferers, suggesting an independence of the abilities to exploit these modulations and the spatial separation of sources. Finally, a model predicting binaural intelligibility for modulated noises was developed and provided a good fit to the experimental data.
Material and shape optimization for multi-layered vocal fold models using transient loadings
Authors: Schmidt Bastian , Leugering Günter , Stingl Michael , Hüttner Björn , Agaimy Abbas , Döllinger Michael
Published: August 2013

Commonly applied models to study vocal fold vibrations in combination with air flow distributions are self-sustained physical models of the larynx consisting of artificial silicone vocal folds. Choosing appropriate mechanical parameters and layer geometries for these vocal fold models while considering simplifications due to manufacturing restrictions is difficult but crucial for achieving realistic behavior. In earlier work by Schmidt et al. [J. Acoust. Soc. Am. 129, 2168–2180 (2011)], the authors presented an approach in which material parameters of a static numerical vocal fold model were optimized to achieve an agreement of the displacement field with data retrieved from hemilarynx experiments. This method is now generalized to a fully transient setting. Moreover in addition to the material parameters, the extended approach is capable of finding optimized layer geometries. Depending on chosen material restriction, significant modifications of the reference geometry are predicted. The additional flexibility in the design space leads to a significantly more realistic deformation behavior. At the same time, the predicted biomechanical and geometrical results are still feasible for manufacturing physical vocal fold models consisting of several silicone layers. As a consequence, the proposed combined experimental and numerical method is suited to guide the construction of physical vocal fold models.
Dynamics of bubbles created by plasma in heptane for micro-gap conditions
Authors: Hamdan A. , Noel C. , Kosior F. , Henrion G. , Belmonte T.
Published: August 2013

The determination of the initial pressure at the bubble wall created by a discharge in heptane for micro-gap conditions cannot be determined straightforwardly by modeling the time-oscillations of the bubble. The resolution of the Gilmore equation gives the same solutions beyond 1 μs typically for various sets of initial parameters, making impossible the determination of the initial pressure at the bubble wall. Furthermore, the very first instant of the bubble formation is not easily accessible at very short time scales because of the plasma emission. Since the pressure waves propagate in the liquid, it is much easier to gain information on the first instants of the bubble formation by studying the pressure field far from the emission source. Then, it is possible to deduce by modeling what happened at the beginning of the emission of the pressure waves. The proposed solution consists in looking at the oscillations affecting another bubble located at least twice farther from the interelectrode gap than the maximum radius reached by the discharge bubble. The initial plasma pressure can be determined by this method.
Theory of the directionality and spatial coherence of wind-driven ambient noise in a deep ocean with attenuation
Authors: Buckingham Michael J.
Published: August 2013

Acoustic attenuation in seawater usually has little effect on the spatial statistics of ambient noise in the ocean. This expectation does not hold, however, at higher frequencies, above 10 kHz, and extreme depths, in excess of 6 km, an operating regime that is within the capabilities of the most recently developed acoustic instrument platforms. To quantify the effects of attenuation, theoretical models for the vertical directionality and the spatial coherence of wind-generated ambient noise are developed in this paper, based on a uniform distribution of surface sources above a semi-infinite, homogeneous ocean. Since there are no bottom reflections, all the noise is downward traveling; and the angular width of the directional density function becomes progressively narrower with increasing frequency because sound from the more distant sources experiences greater attenuation than acoustic arrivals from overhead. This narrowing of the noise lobe modifies the spatial coherence, shifting the zeros in the horizontal (vertical) coherence function to higher (lower) frequencies. In addition, the attenuation modifies the amplitudes of the higher-order oscillations in the horizontal and vertical coherence functions, tending to suppress the former and enhance the latter. These effects are large enough to be detectable with the latest deep-diving sensor technology.
The dominant region for the pitch of complex tones with low fundamental frequencies
Authors: Jackson Helen M. , Moore Brian C. J.
Published: August 2013

The dominant region for pitch for complex tones with low fundamental frequency (F0) was investigated. Thresholds for detection of a change in F0 (F0DLs) were measured for a group of harmonics (group B) embedded in a group of fixed non-overlapping harmonics (group A) with the same mean F0. It was assumed that F0DLs would be smallest when the harmonics in group B fell in the dominant region. The rank of the lowest harmonic in group B, N, was varied from 1 to 15. When all components had the same level, F0DLs increased with increasing N, but the increase started at a lower value of N for F0 = 200 Hz than for F0 = 50 or 100 Hz, the opposite of what would be expected if the dominant region corresponds to resolved harmonics. When the component levels followed an equal-loudness contour, F0DLs for F0 = 50 Hz were lowest for N = 1, but overall performance was much worse than for equal-level components, suggesting that the lowest harmonics were masking information from the higher harmonics.
Influence of stimulus parameters on amplitude-modulated stimulus frequency otoacoustic emissions
Authors: Johnson Tiffany A. , Beshaler Laura
Published: August 2013

The present study evaluated the influence of suppressor frequency (fs) and level (Ls) on stimulus-frequency otoacoustic emissions (SFOAEs) recorded using the amplitude-modulated (AM) suppressor technique described by Neely et al. [J. Acoust. Soc. Am. 118, 2124-2127 (2005a)]. Data were collected in normal-hearing subjects, with data collection occurring in two phases. In phase 1, SFOAEs were recorded with probe frequency (fp) = 1, 2, and 4 kHz and probe levels (Lp) ranging from 0 to 60 dB sound pressure level (SPL). At each fp, Ls ranged from Ls = Lp to Ls = Lp + 30 dB. Additionally, nine relationships between fs and fp were evaluated, ranging from fs/fp = 0.80 to fs/fp = 1.16. Results indicated that for low suppressor levels, suppressors higher in frequency than fp (fs > fp) resulted in higher AM-SFOAE levels than suppressors lower in frequency than fp (fs < fp). At higher suppressor levels, suppressors both higher and lower in frequency than fp produced similar AM-SFOAE levels, and, in many cases, low-frequency suppressors produced the largest response. Recommendations for stimulus parameters that maximize AM-SFOAE level were derived from these data. In phase 2, AM-SFOAEs were recorded using these parameters for fp = 0.7-8 kHz and Lp = 20-60 dB SPL. Robust AM-SFOAE responses were recorded in this group of subjects using the parameters developed in phase 1.
Effect of train type on annoyance and acoustic features of the rolling noise
Authors: Kasess Christian H. , Noll Anton , Majdak Piotr , Waubke Holger
Published: August 2013

This study investigated the annoyance associated with the rolling noise of different railway stock. Passbys of nine train types (passenger and freight trains) equipped with different braking systems were recorded. Acoustic features showed a clear distinction of the braking system with the A-weighted energy equivalent sound level (LAeq) showing a difference in the range of 10 dB between cast-iron braked trains and trains with disk or K-block brakes. Further, annoyance was evaluated in a psychoacoustic experiment where listeners rated the relative annoyance of the rolling noise for the different train types. Stimuli with and without the original LAeq differences were tested. For the original LAeq differences, the braking system significantly affected the annoyance with cast-iron brakes being most annoying, most likely as a consequence of the increased wheel roughness causing an increased LAeq. Contribution of the acoustic features to the annoyance was investigated revealing that the LAeq explained up to 94% of the variance. For the stimuli without differences in the LAeq, cast-iron braked train types were significantly less annoying and the spectral features explained up to 60% of the variance in the annoyance. The effect of these spectral features on the annoyance of the rolling noise is discussed.
Response to “Comments on ‘A theoretical model of the pressure distributions arising from asymmetric intraglottal flows applied to a two-mass model of the vocal folds’” [J. Acoust. Soc. Am. 130, 389–403 (2011)]
Authors: Erath Byron D. , Peterson Sean D. , Zañartu Matías , Wodicka George R. , Stewart Kelley C. , Plesniak Michael W.
Published: August 2013

Hirschberg [J. Acoust. Soc. Am. 134, 9-12 (2013)] presents a commentary and criticisms of the viscous flow model presented by Erath et al. [J. Acoust. Soc. Am. 130, 389–403 (2011)] that solves for the asymmetric pressure loading on the vocal fold walls. This pressure loading arises from asymmetric flow attachment to one vocal fold wall when the glottal channel forms a divergent configuration. Hirschberg proposes an alternative model for the asymmetric loading based upon inviscid flow curvature at the glottal inlet. In this manuscript further evidence is provided in support of the model of Erath et al. and the underlying assumptions, and demonstrates that the primary criticisms presented by Hirschberg are unwarranted. The model presented by Hirschberg is compared with the model from the original paper by Erath et al., and it is shown that each model describes different and complementary aspects of divergent glottal flows.
Quantitative non-linear ultrasonic imaging of targets with significant acoustic impedance contrast—An experimental study
Authors: Guillermin Régine , Lasaygues Philippe , Rabau Guy , Lefebvre Jean-Pierre
Published: August 2013

This study deals with the reconstruction, from ultrasonic measured data, of the sound speed profile of a penetrable two-dimensional target of arbitrary cross-section embedded in an infinite medium. Green's theorem is used to obtain a domain integral representation of the acoustical scattered field, and a discrete formulation of the inverse problem is obtained using a moment method. An iterative non-linear algorithm minimizing the discrepancy between the measured and computed scattered fields is used to reconstruct the sound speed profile in the region of interest. The minimization process is performed using a conjugated-gradient method. An experimental study with significant acoustical impedance contrast targets immersed in water was performed. Images of the sound speed profile obtained by inversion of experimental data are presented.
Model for the dynamics of a spherical bubble undergoing small shape oscillations between parallel soft elastic layers
Authors: Hay Todd A. , Ilinskii Yurii A. , Zabolotskaya Evgenia A. , Hamilton Mark F.
Published: August 2013

A model is developed for a pulsating and translating gas bubble immersed in liquid in a channel formed by two soft, thin elastic parallel layers having densities equal to that of the surrounding liquid and small, but finite, shear moduli. The bubble is nominally spherical but free to undergo small shape deformations. Shear strain in the elastic layers is estimated in a way which is valid for short, transient excitations of the system. Coupled nonlinear second-order differential equations are obtained for the shape and position of the bubble, and numerical integration of an expression for the liquid velocity at the layer interfaces yields an estimate of the elastic layer displacement. Numerical integration of the dynamical equations reveals behavior consistent with laboratory observations of acoustically excited bubbles in ex vivo vessels reported by Chen et al. [Phys. Rev. Lett. 106, 034301 (2011) and Ultrasound Med. Biol. 37, 2139–2148 (2011)].
Controlling collagen fiber microstructure in three-dimensional hydrogels using ultrasound
Authors: Garvin Kelley A. , VanderBurgh Jacob , Hocking Denise C. , Dalecki Diane
Published: August 2013

Type I collagen is the primary fibrillar component of the extracellular matrix, and functional properties of collagen arise from variations in fiber structure. This study investigated the ability of ultrasound to control collagen microstructure during hydrogel fabrication. Under appropriate conditions, ultrasound exposure of type I collagen during polymerization altered fiber microstructure. Scanning electron microscopy and second-harmonic generation microscopy revealed decreased collagen fiber diameters in response to ultrasound compared to sham-exposed samples. Results of mechanistic investigations were consistent with a thermal mechanism for the effects of ultrasound on collagen fiber structure. To control collagen microstructure site-specifically, a high frequency, 8.3-MHz, ultrasound beam was directed within the center of a large collagen sample producing dense networks of short, thin collagen fibrils within the central core of the gel and longer, thicker fibers outside the beam area. Fibroblasts seeded onto these gels migrated rapidly into small, circularly arranged aggregates only within the beam area, and clustered fibroblasts remodeled the central, ultrasound-exposed collagen fibrils into dense sheets. These investigations demonstrate the capability of ultrasound to spatially pattern various collagen microstructures within an engineered tissue noninvasively, thus enhancing the level of complexity of extracellular matrix microenvironments and cellular functions achievable within three-dimensional engineered tissues.
Transcostal high-intensity focused ultrasound treatment using phased array with geometric correction
Authors: Qiao Shan , Shen Guofeng , Bai Jingfeng , Chen Yazhu
Published: August 2013

In the high-intensity focused ultrasound treatment of liver tumors, ultrasound propagation is affected by the rib cage. Because of the diffraction and absorption of the bone, the sound distribution at the focal plane is altered, and more importantly, overheating on the rib surface might occur. To overcome these problems, a geometric correction method is applied to turn off the elements blocked by the ribs. The potential of steering the focus of the phased-array along the propagation direction to improve the transcostal treatment was investigated by simulations and experiments using different rib models and transducers. The ultrasound propagation through the ribs was computed by a hybrid method including the Rayleigh–Sommerfeld integral, k-space method, and angular spectrum method. A modified correction method was proposed to adjust the output of elements based on their relative area in the projected “shadow” of the ribs. The simulation results showed that an increase in the specific absorption rate gain up to 300% was obtained by varying the focal length although the optimal value varied in each situation. Therefore, acoustic simulation is required for each clinical case to determine a satisfactory treatment plan.
Ultrasound thermal mapping based on a hybrid method combining cross-correlation and zero-crossing tracking
Authors: Huang Chang-Wei , Lien Der-Hsien , Chen Ben-Ting , Shieh Jay , Tsui Po-Hsiang , Chen Chuin-Shan , Chen Wen-Shiang
Published: August 2013

A hybrid method for estimating temperature with spatial mapping using diagnostic ultrasound, based on detection of echo shifts from tissue undergoing thermal treatment, is proposed. Cross-correlation and zero-crossing tracking are two conventional algorithms used for detecting echo shifts, but their practical applications are limited. The proposed hybrid method combines the advantages of both algorithms with improved accuracy in temperature estimation. In vitro experiments were performed on porcine muscle for preliminary validation and temperature calibration. In addition, thermal mapping of rabbit thigh muscle in vivo during high-intensity focused ultrasound heating was conducted. Results from the in vitro experiments indicated that the difference between the estimated temperature change by the proposed hybrid method and the actual temperature change measured by the thermocouple was generally less than 1 °C when the increase in temperature due to heating was less than 10 °C. For the in vivo study, the area predicted to experience the highest temperature coincided well with the focal point of the high-intensity focused ultrasound transducer. The computational efficiency of the hybrid algorithm was similar to that of the fast cross-correlation algorithm, but with an improved accuracy. The proposed hybrid method could provide an alternative means for non-invasive monitoring of limited temperature changes during hyperthermia therapy.
Low-frequency (<100 kHz), low-intensity (<100 mW/cm2) ultrasound to treat venous ulcers: A human study and in vitro experiments
Authors: Samuels Joshua A. , Weingarten Michael S. , Margolis David J. , Zubkov Leonid , Sunny Youhan , Bawiec Christopher R. , Conover Dolores , Lewin Peter A.
Published: August 2013

The purpose of this study was to examine whether low frequency (<100 kHz), low intensity (<100 mW/cm2, spatial peak temporal peak) ultrasound can be an effective treatment of venous stasis ulcers, which affect 500 000 patients annually costing over $1 billion per year. Twenty subjects were treated with either 20 or 100 kHz ultrasound for between 15 and 45 min per session for a maximum of four treatments. Healing was monitored by changes in wound area. Additionally, two in vitro studies were conducted using fibroblasts exposed to 20 kHz ultrasound to confirm the ultrasound's effects on proliferation and cellular metabolism. Subjects receiving 20 kHz ultrasound for 15 min showed statistically faster (p < 0.03) rate of wound closure. All five of these subjects fully healed by the fourth treatment session. The in vitro results indicated that 20 kHz ultrasound at 100 mW/cm2 caused an average of 32% increased metabolism (p < 0.05) and 40% increased cell proliferation (p < 0.01) after 24 h when compared to the control, non-treated cells. Although statistically limited, this work supports the notion that low-intensity, low-frequency ultrasound is beneficial for treating venous ulcers.
Experimentally validated multiphysics computational model of focusing and shock wave formation in an electromagnetic lithotripter
Authors: Fovargue Daniel E. , Mitran Sorin , Smith Nathan B. , Sankin Georgy N. , Simmons Walter N. , Zhong Pei
Published: August 2013

A multiphysics computational model of the focusing of an acoustic pulse and subsequent shock wave formation that occurs during extracorporeal shock wave lithotripsy is presented. In the electromagnetic lithotripter modeled in this work the focusing is achieved via a polystyrene acoustic lens. The transition of the acoustic pulse through the solid lens is modeled by the linear elasticity equations and the subsequent shock wave formation in water is modeled by the Euler equations with a Tait equation of state. Both sets of equations are solved simultaneously in subsets of a single computational domain within the BEARCLAW framework which uses a finite-volume Riemann solver approach. This model is first validated against experimental measurements with a standard (or original) lens design. The model is then used to successfully predict the effects of a lens modification in the form of an annular ring cut. A second model which includes a kidney stone simulant in the domain is also presented. Within the stone the linear elasticity equations incorporate a simple damage model.
Investigation on the inertial cavitation threshold and shell properties of commercialized ultrasound contrast agent microbubbles
Authors: Guo Xiasheng , Li Qian , Zhang Zhe , Zhang Dong , Tu Juan
Published: August 2013

The inertial cavitation (IC) activity of ultrasound contrast agents (UCAs) plays an important role in the development and improvement of ultrasound diagnostic and therapeutic applications. However, various diagnostic and therapeutic applications have different requirements for IC characteristics. Here through IC dose quantifications based on passive cavitation detection, IC thresholds were measured for two commercialized UCAs, albumin-shelled KangRun® and lipid-shelled SonoVue® microbubbles, at varied UCA volume concentrations (viz., 0.125 and 0.25 vol. %) and acoustic pulse lengths (viz., 5, 10, 20, 50, and 100 cycles). Shell elastic and viscous coefficients of UCAs were estimated by fitting measured acoustic attenuation spectra with Sarkar's model. The influences of sonication condition (viz., acoustic pulse length) and UCA shell properties on IC threshold were discussed based on numerical simulations. Both experimental measurements and numerical simulations indicate that IC thresholds of UCAs decrease with increasing UCA volume concentration and acoustic pulse length. The shell interfacial tension and dilatational viscosity estimated for SonoVue (0.7 ± 0.11 N/m, 6.5 ± 1.01 × 10−8 kg/s) are smaller than those of KangRun (1.05 ± 0.18 N/m, 1.66 ± 0.38 × 10−7 kg/s); this might result in lower IC threshold for SonoVue. The current results will be helpful for selecting and utilizing commercialized UCAs for specific clinical applications, while minimizing undesired IC-induced bioeffects.
Surface vibration and nearby cavitation of an ex vivo bovine femur exposed to high intensity focused ultrasound
Authors: Zhang Siyuan , Li Chong , Yin Hui , Wang Supin , Wan Mingxi
Published: August 2013

The acoustic pressure distribution, thermal ablation, and sonochemiluminescence (SCL) generated by cavitation near the surface of an ex vivo bovine femur were investigated at normal and oblique incidences of high intensity focused ultrasound (HIFU), as were the characteristics of bone surface vibrations. The acoustic pressure at the HIFU focus, the width of thermal ablation, and the SCL intensity in the pre-focal region were 1.3 MPa, 7 mm, and 454 electrons, respectively, in the control group at normal incidence, and they respectively increased to 1.5 MPa, 12 mm and 968 electrons in the presence of the bone. At oblique incidence from the left, the acoustic pressure at 3 mm to the right of the HIFU focus was 0.6 MPa and decreased to 0.4 MPa at 3 mm to the left of the focus. The thermal ablation was 20 mm in width and extended along the front surface of the bone to the right of the HIFU focus. The SCL intensity on the right of the HIFU focus was 394 electrons and was 362 electrons on the left. The presence of bone would directionally change the spatial distribution of acoustic pressure, thermal and cavitation effects for oblique incidence of HIFU.
Computational study on the propagation of strongly focused nonlinear ultrasound in tissue with rib-like structures
Authors: Lin Jiexing , Liu Xiaozhou , Gong Xiufen , Ping Zihong , Wu Junru
Published: August 2013

The presence of a rib cage is a significant hindrance to the potential applications of focused ultrasound as a noninvasive extracorporeal surgery modality for various internal organs. Here the influence of ribs on the propagation of strongly focused high-intensity nonlinear ultrasound beam inside the body is studied. Based on the spheroidal beam equation, a three-dimensional numerical algorithm is developed to solve the nonlinear acoustic field generated by a focused ultrasonic transducer with a large aperture angle. Idealized ribs, of rectangular cross sectional, with high absorption and impedance, and various dimensions, are used to simulate human anatomical configurations. The changes in the spatial distribution of acoustic intensity and the reduction of the acoustic pressure amplitude and heat deposition rate due to the presence of “ribs” are investigated. It is somewhat surprising that in some cases, the axial peak positions shift less than 2 mm and more than 80% of the sound energy can propagate through the space of the rib cage in the strongly focused sound field. This study also includes quantitative analyses of the effects of different rib configurations and transducers of various f-numbers. The results can be used as reference information for further study and clinical applications.