bluuebunny/crossref_metadata_2025 huggingface dataset:
Presence of viruses in wild eels Anguilla anguilla L, from the Albufera Lake (Spain)
Authors: Bandín I , Souto S , Cutrín J M , López‐Vázquez C , Olveira J G , Esteve C , Alcaide E , Dopazo C P
Published: May 2014

A virological analysis was conducted on wild eels from the Albufera Lake (Spain). A total of 179 individuals at different growth stages were collected in two different surveys (2004 and 2008). Presence of anguillid herpesvirus (AngHV‐1), aquabirnavirus and betanodavirus was confirmed by PCR procedures in both surveys, although the number of detections was clearly higher in 2008 (83% of the eels analysed resulted positive for virus presence). AngHV‐1 was the viral agent most frequently detected, followed by aquabirnaviruses. Betanodaviruses were detected by the first time in wild eels, and although the detections were only made by nested PCR, high percentage of positives were achieved. In addition, in 2008, seven aquabirnaviruses were isolated. Phylogenetic analysis performed using partial sequences of both genomic segments of aquabirnaviruses indicated that the seven isolates could be typed as WB (genogroup I) on the basis of segment A sequences, but when segment B was used six of them clustered with C1 strain (genogroup V) and one was typed as Ab (genogroup II). These results indicate natural reassortment between different strains of aquabirnaviruses in the eels. Although betanodaviruses were not isolated in cell culture, the analysis of the sequence of the nested PCR product indicated that they clustered with SJNNV genotype. The diversity of viral agents and the high level of viral detections suggest that viral infections may play a more prominent role in the decline of the European eel than initially thought.
Reduced fecundity in non‐parasitic lampreys may not be due to heterochronic shift in ovarian differentiation
Authors: Spice E. K. , Docker M. F.
Published: May 2014

Heterochrony is an important mechanism for the evolution of differences between and within species. In lampreys, heterochrony has been suggested as a mechanism contributing to fecundity differences in non‐parasitic versus parasitic species. Non‐parasitic lampreys, which do not feed at all after metamorphosis, have much smaller body sizes at maturation and therefore much lower fecundity than parasitic lampreys. Previous studies have suggested that this fecundity difference is established in the larval stage through ovarian differentiation at a younger age (and therefore smaller body size) in non‐parasitic females, leading to production of fewer oocytes. The current study examined whether this pattern is applicable in two additional lamprey species. The timing of histological ovarian differentiation was determined in larval parasitic chestnut lamprey Ichthyomyzon castaneus and non‐parasitic northern brook lamprey I. fossor in southeastern Manitoba, Canada, and potential fecundity was compared through oocyte counts in differentiated females of both species. Ovarian differentiation occurred in age classes 1 and 2 in both chestnut and northern brook lampreys, and there were no significant differences in the timing of ovarian differentiation between species; this indicates that the timing of ovarian differentiation is not a reliable marker of life history type. Factors such as growth and body condition may determine whether an individual undergoes ovarian differentiation in age class 1 or 2. Chestnut and northern brook lampreys had similar minimum oocyte counts; however, the average and maximum oocyte counts were higher in chestnut lamprey in each age class. As the timing of ovarian differentiation is similar in chestnut and northern brook lampreys, the higher potential fecundity of chestnut lamprey must originate through mechanisms other than heterochrony.
The metabolic enzyme AdhE controls the virulence of Escherichia coli O157:H7
Authors: Beckham Katherine S. H. , Connolly James P. R. , Ritchie Jennifer M. , Wang Dai , Gawthorne Jayde A. , Tahoun Amin , Gally David L. , Burgess Karl , Burchmore Richard J. , Smith Brian O. , Beatson Scott A. , Byron Olwyn , Wolfe Alan J. , Douce Gillian R. , Roe Andrew J.
Published: May 2014

Classical studies have focused on the role that individual regulators play in controlling virulence gene expression. An emerging theme, however, is that bacterial metabolism also plays a key role in this process. Our previous work identified a series of proteins that were implicated in the regulation of virulence. One of these proteins was AdhE, a bi‐functional acetaldehyde‐CoA dehydrogenase and alcohol dehydrogenase. Deletion of its gene (adhE) resulted in elevated levels of extracellular acetate and a stark pleiotropic phenotype: strong suppression of the Type Three Secretion System (T3SS) and overexpression of non‐functional flagella. Correspondingly, the adhE mutant bound poorly to host cells and was unable to swim. Furthermore, the mutant was significantly less virulent than its parent when tested in vivo, which supports the hypothesis that attachment and motility are central to the colonization process. The molecular basis by which AdhE affects virulence gene regulation was found to be multifactorial, involving acetate‐stimulated transcription of flagella expression and post‐transcriptional regulation of the T3SS through Hfq. Our study reveals fascinating insights into the links between bacterial physiology, the expression of virulence genes, and the underlying molecular mechanism mechanisms by which these processes are regulated.
Defective Kernel 1 (DEK1) is required for three‐dimensional growth in Physcomitrella patens
Authors: Perroud Pierre‐François , Demko Viktor , Johansen Wenche , Wilson Robert C. , Olsen Odd‐Arne , Quatrano Ralph S.
Published: May 2014

Orientation of cell division is critical for plant morphogenesis. This is evident in the formation and function of meristems and for morphogenetic transitions. Mosses undergo such transitions: from two‐dimensional tip‐growing filaments (protonema) to the generation of three‐dimensional leaf‐like structures (gametophores).

The Defective Kernel 1 (DEK1) protein plays a key role in the perception of and/or response to positional cues that specify the formation and function of the epidermal layer in developing seeds of flowering plants. The moss Physcomitrella patens contains the highly conserved DEK1 gene.

Using efficient gene targeting, we generated a precise PpDEK1 deletion (∆dek1), which resulted in normal filamentous growth of protonema. Two distinct mutant phenotypes were observed: an excess of buds on the protonema, and abnormal cell divisions in the emerging buds resulting in developmental arrest and the absence of three‐dimensional growth. Overexpression of a complete PpDEK1 cDNA, or the calpain domain of PpDEK1 alone, successfully complements both phenotypes.

These results in P. patens demonstrate the morphogenetic importance of the DEK1 protein in the control of oriented cell divisions. As it is not for protonema, it will allow dissection of the structure/function relationships of the different domains of DEK1 using gene targeting in null mutant background.
The intracellular delivery of TAT‐aequorin reveals calcium‐mediated sensing of environmental and symbiotic signals by the arbuscular mycorrhizal fungus Gigaspora margarita
Authors: Moscatiello Roberto , Sello Simone , Novero Mara , Negro Alessandro , Bonfante Paola , Navazio Lorella
Published: May 2014

Arbuscular mycorrhiza (AM) is an ecologically relevant symbiosis between most land plants and Glomeromycota fungi. The peculiar traits of AM fungi have so far limited traditional approaches such as genetic transformation. The aim of this work was to investigate whether the protein transduction domain of the HIV‐1 transactivator of transcription (TAT) protein, previously shown to act as a potent nanocarrier for macromolecule delivery in both animal and plant cells, may translocate protein cargoes into AM fungi.

We evaluated the internalization into germinated spores of Gigaspora margarita of two recombinant TAT fusion proteins consisting of either a fluorescent (GFP) or a luminescent (aequorin) reporter linked to the TAT peptide.

Both TAT‐fused proteins were found to enter AM fungal mycelia after a short incubation period (5–10 min). Ca2+ measurements in G. margarita mycelia pre‐incubated with TAT‐aequorin demonstrated the occurrence of changes in the intracellular free Ca2+ concentration in response to relevant stimuli, such as touch, cold, salinity, and strigolactones, symbiosis‐related plant signals.

These data indicate that the cell‐penetrating properties of the TAT peptide can be used as an effective strategy for intracellularly delivering proteins of interest and shed new light on Ca2+ homeostasis and signalling in AM fungi.
Regulation of immune responses by neutrophils
Authors: Wang Jing , Arase Hisashi
Published: May 2014

Neutrophils, the most abundant circulating cells in humans, are major pathogen‐killing immune cells. For many years, these cells were considered to be simple killers at the “bottom” of immune responses. However, recent studies have revealed more sophisticated mechanisms associated with neutrophilic cytotoxic functions, and neutrophils have been shown to contribute to various infectious and inflammatory diseases. In this review, we discuss the key features of neutrophils during inflammatory responses, from their release from the bone marrow to their death in inflammatory loci. We also discuss the expanding roles of neutrophils that have been identified in the context of several inflammatory diseases. We further focus on the mechanisms that regulate neutrophil recruitment to inflamed tissues and neutrophil cytotoxic activities against both pathogens and host tissues.
Associations between sedentary behaviour and physical activity in children and adolescents: a meta‐analysis
Authors: Pearson N. , Braithwaite R. E. , Biddle S. J. H. , van Sluijs E. M. F. , Atkin A. J.
Published: May 2014

Physical activity and sedentary behaviour are associated with metabolic and mental health during childhood and adolescence. Understanding the inter‐relationships between these behaviours will help to inform intervention design. This systematic review and meta‐analysis synthesized evidence from observational studies describing the association between sedentary behaviour and physical activity in young people (<18 years). English‐language publications up to August 2013 were located through electronic and manual searches. Included studies presented statistical associations between at least one measure of sedentary behaviour and one measure of physical activity. One hundred sixty‐three papers were included in the meta‐analysis, from which data on 254 independent samples was extracted. In the summary meta‐analytic model (k = 230), a small, but significant, negative association between sedentary behaviour and physical activity was observed (r = −0.108, 95% confidence interval [CI] = −0.128, −0.087). In moderator analyses, studies that recruited smaller samples (n < 100, r = −0.193, 95% CI = −0.276, −0.109) employed objective methods of measurement (objectively measured physical activity; r = −0.233, 95% CI = −0.330, −0.137) or were assessed to be of higher methodological quality (r = −0.176, 95% CI = −0.215, −0.138) reported stronger associations, although effect sizes remained small. The association between sedentary behaviour and physical activity in young people is negative, but small, suggesting that these behaviours do not directly displace one another.
Interim Response of Dissolved Oxygen to Reestablished Flow in the Kissimmee River, Florida, U.S.A.
Authors: Colangelo David J.
Published: May 2014

Restoration of the Kissimmee River should have multiple ecological benefits including improved dissolved oxygen (DO) within the river channel. Channelization of the Kissimmee River virtually eliminated flow through the natural river channel. After channelization, chronically low DO concentrations were observed in the stagnant remnant channel. Although no DO data from before channelization exist, reference estimates of pre‐channelization conditions were derived from seven relatively unimpacted streams. Stations along the Kissimmee River were sampled for 3 years before construction of the first phase of the restoration project began and for up to 8 years after the completion of construction. After Phase I construction, DO concentrations in the area of the river channel to which flow had been restored increased significantly from 2.2 to 4.9 mg/L, which is similar to DO concentrations observed in the reference streams. Mean DO concentrations for the reference streams ranged from 4.6 to 6.7 mg/L. Comparison of reference data to data from the pre‐Phase I and post‐Phase I system suggests that channelization had a negative impact on DO and that DO concentrations in the post‐Phase I Kissimmee River channel have made a significant recovery. Long‐term data trends demonstrate that DO concentrations can be negatively impacted by high flow events and that recovery from these events is generally quick, suggesting some degree of resilience in the system.
Quantifying Inefficient Expenditure in Local Government: A Free Disposable Hull Analysis of a Sample of South African Municipalities
Authors: Mahabir Jugal
Published: May 2014

Municipalities in South Africa play a pivotal role in the provision of basic services to communities. However, local government as a sphere in the country is notorious for its spending inefficiency, which is cited as a major factor in service delivery failure. This paper quantifies inefficient expenditure at the local government level by estimating efficiency scores for a sample of 129 municipalities in South Africa from the 2005/2006 to the 2009/2010 municipal financial years. In essence, this paper examines the technical efficiency of municipalities by using the nonparametric free disposable hull approach and finds that 10 municipalities are constantly efficient over the period. On average, input efficiency scores range from 42% to 46%, suggesting that, in general, municipalities can achieve the same output levels with over 50% less resources. Quantitatively for the 2009/2010 financial year, this amounts to a total of R80 billion being spent inefficiently, which equates to R220 million being “wasted” per day.
The Expression ofHMGB1 on Microparticles from Jurkat andHL‐60 Cells Undergoing Apoptosisin vitro
Authors: Spencer D. M. , Mobarrez F. , Wallén H. , Pisetsky D. S.
Published: May 2014

HMGB1 is a highly conserved nuclear protein that displays important biological activities inside as well as outside the cell and serves as a prototypic alarmin to activate innate immunity. The translocation ofHMGB1 from inside to outside the cell occurs with cell activation as well as cell death, including apoptosis. Apoptosis is also a setting for the release of cellular microparticles (MPs), which are small membrane‐bound vesicles that represent an important source of extracellular nuclear molecules. To investigate whetherHMGB1 released from cells during apoptosis is also present onMPs, we determined the presence ofHMGB1 on particles released from Jurkat andHL‐60 cells induced to undergo apoptosisin vitroby treatment with either etoposide or staurosporine;MPs released from cells undergoing necrosis by freeze–thaw were also characterized. As shown by both Western blot analysis and flow cytometry,MPs from apoptotic cells containHMGB1, with binding by antibodies indicating an accessible location in the particle structure. These results indicate thatHMGB1, like other nuclear molecules, can translocate intoMPs during apoptosis and demonstrate another biochemical form of this molecule that may be immunologically active.
Lacan on urban development and national identity in a global city: Integrated Resorts in Singapore
Authors: Bullock Nathan F.
Published: May 2014

Lacanian psychoanalysis has been used in film, literature and other areas of social thought, but rarely in the domain of urban studies and human/cultural geography. Following its introduction by urban planners Michael Gunder and Jean Hillier, I apply the theory of the four discourses and the mirror stage of development to Singapore's urban development of the two Integrated Resorts at Marina Bay and Sentosa. The decision to allow gambling and build casinos was a contentious one and provides a point of departure for insight into the identity issues and planning decision making processes in Singapore. I critically analyse the rhetoric of the public debate from 2004–2005 to draw conclusions about the government's self‐perception of Singapore as a city‐state and the manifestation of this identity through the creation of cosmopolitan spaces as an attempt to project that identity onto its citizens. The aim of Lacanian psychoanalysis is to provide an understanding and recognition by analysis to enable a change of signifiers, values and ideology among the masters and the subjects to better represent the true needs and wants of the community. This reflective position enables a movement toward postcolonial urban studies and planning.
Combined magnetic fields accelerate bone‐tendon junction injury healing through osteogenesis
Authors: Hu J. , Zhang T. , Xu D. , Qu J. , Qin L. , Zhou J. , Lu H.
Published: May 2014

The objective of this study was to explore the effect of combined magnetic fields (CMFs) on osteogenesis and the remodeling of newly formed bone at bone‐tendon (BT) junction. Forty‐eight mature rabbits in whom partial patellectomy was performed were used to establish a BT junction injury model at the patella‐patellar tendon (PPT) complex and were then allocated to CMF treatment group (CMF group) or placebo treatment group (control group). Daily CMF therapy was delivered continuously from post‐operative day 3 to weeks 4, 8, and 16. At each time point, the animals were sacrificed, and the PPT complexes were harvested for radiographic, histological, peripheral quantitative computed tomography, and micro‐computed tomography (micro‐CT) evaluation. The area, length, and bone mineral density of the newly formed bone in the CMF group were significantly greater than the control group at post‐operative weeks 8 and 16. The micro‐CT results showed that the newly formed bone in the CMF group contained more and thicker trabeculae than the control group at weeks 8 and 16. Histologically, the CMF group showed better remodeling of the BT junction. In conclusion, CMF treatment was able to accelerate osteogenesis during BT junction repair, thus facilitating the healing of BT junction injury.
Transfusion‐related acute lung injury–associated HNA‐3a antibodies recognize complex determinants on choline transporter‐like protein 2
Authors: Bougie Daniel W. , Peterson Julie A. , Kanack Adam J. , Curtis Brian R. , Aster Richard H.
Published: May 2014

Background

HNA‐3a–specific antibodies can cause severe, sometimes fatal, transfusion‐related acute lung injury when present in transfused blood. The HNA3‐a/b antigens are determined by an R154Q polymorphism in the first of five extracellular (EC) loops of the 10‐membrane‐spanning choline transporter‐like protein 2 (CTL2) expressed on neutrophils, lymphocytes, and other tissues. Approximately 50% of HNA‐3a antibodies (Type 1) can be detected using CTL2 Loop 1 peptides containing R154; the remaining 50% (Type 2) fail to recognize this target. Understanding the basis for this difference could guide efforts to develop practical assays to screen blood donors for HNA‐3 antibodies.

Study Design and Methods

Reactions of HNA‐3a antibodies against recombinant versions of human, mouse, and human/mouse (chimeric) CTL2 were characterized using flow cytometry and various solid‐phase assays.

Results

The findings show that, for binding to CTL2, Type 2 HNA‐3a antibodies require nonpolymorphic amino acid residues in the third, and possibly the second, EC loops of CTL2 to be in a configuration comparable to that found naturally in the cell membrane. In contrast, Type 1 antibodies require only peptides from the first EC loop that contain R154 for recognition.

Conclusion

Although Type 1 HNA‐3a antibodies can readily be detected in solid‐phase assays that use a CTL2 peptide containing R154 as a target, development of a practical test to screen blood donors for Type 2 antibodies will pose a serious technical challenge because of the complex nature of the epitope(s) recognized by this antibody subgroup.
ALTRUISM AND THE GOLDEN RULE
Authors: Goodman Jonathan
Published: May 2014

This essay addresses recent claims about the compatibility of the sociobiological theory of reciprocal altruism with standard Western formulations of the Golden Rule. Derek Parfit claims that the theory of reciprocal altruism teaches us to be “reciprocal altruists,” who benefit only those people from whom we can reasonably expect benefits in the future. The Golden Rule, on the other hand, teaches us to benefit anyone regardless of their intention or ability to return the favor, or as Parfit puts it, the Golden Rule teaches us to be “suckers.” I argue that this distinction is founded on a misconception of the nature of the theory of reciprocal altruism, which is sociobiological as opposed to moral, and that this distinction accordingly confusesiswithought. Sociobiological theories may explain underlying psychological motivations in individuals (and perhaps even in populations), but these theories do not prescribe any sort of moral behavior. Furthermore, the theory of reciprocal altruism does not imply mental states of which agents are aware. The unconscious motivations assumed by this theory are in fact compatible with certain formulations of the Golden Rule; I will accordingly argue for the view that certain words with moral content related to the Golden Rule—such as “altruism” and “selfishness”—exist only insofar as they are social tools, which can further the self‐interests of an individual in any group.
THE FRUITS OF PLURALISM: A VISION FOR THE NEXT SEVEN YEARS IN RELIGION/SCIENCE
Authors: Clayton Philip
Published: May 2014

This article offers a vision for work at the intersection of science and religion over the coming seven years. Because predictions are inherently risky and are more often than not false, the text first offers an assessment of the current state of the science‐religion discussion and a quick survey of the last 50 years of work in this field. The implications of the six features of this vision for the future of the field are then presented in some detail. Rather than bemoaning the current diversity of approaches and conclusions as a negative result, I endorse it as a healthy sign—if acknowledged honestly and managed well.
METAPHYSICS MATTERS: METAPHYSICS AND SOTERIOLOGY IN JEROME STONE'S AND DONALD CROSBY'S VARIETIES OF RELIGIOUS NATURALISM
Authors: Ruper Stefani
Published: May 2014

Religious naturalism is distinct from supernatural religion largely because of metaphysical minimalism. Certain varieties of religious naturalism are more minimalist than others, however, and some even eschew metaphysics altogether. But is anything lost in that process? To determine metaphysics’ degree of relevance to religious function, I compare the soteriology of the “ontologically reticent”Minimalist Visionof Jerome Stone to that of the ontologically richReligion of Natureof Donald Crosby. I demonstrate that for these varieties of religious naturalism: (1) metaphysics influences soteriology; (2) metaphysical minimalism limits soteriological potential; and (3) metaphysics enhances soteriological potential. These conclusions lead me to assert the relevance of metaphysics to religious function, specifically for these varieties of religious naturalism, as well as to urge investigation into religious experience and quality as they may relate to metaphysics.
Shear Deformation in Rectangular Auxetic Plates
Authors: Lim Teik-Cheng
Published: May 2014

Solids that exhibit negative Poisson's ratio are called auxetic materials. This paper examines the extent of transverse shear deformation with reference to bending deformation in simply supported auxetic plates as a ratio of Mindlin-to-Kirchhoff plate deflection for polygonal plates in general, with special emphasis on rectangular plates. Results for square plates show that the Mindlin plate deflection approximates the Kirchhoff plate deflection not only when the plate thickness is negligible, as is obviously known, but also when (a) the Poisson's ratio of the plate is very negative under all load distributions, as well as (b) at the central portion of the plate when the load is uniformly distributed. Hence geometrically thick plates are mechanically equivalent to thin plates if the plate Poisson's ratio is sufficiently negative. The high suppression of shear deformation in favor of bending deformation in auxetic plates suggests its usefulness for bending-based plate sensors that require larger difference in the in-plane strains between the opposing plate surfaces with minimal transverse deflection.
Evaluation of Global Load Sharing and Shear-Lag Models to Describe Mechanical Behavior in Partially Lacerated Tendons
Authors: Pensalfini Marco , Duenwald-Kuehl Sarah , Kondratko-Mittnacht Jaclyn , Lakes Roderic , Vanderby Ray
Published: May 2014

The mechanical effect of a partial thickness tear or laceration of a tendon is analytically modeled under various assumptions and results are compared with previous experimental data from porcine flexor tendons. Among several fibril-level models considered, a shear-lag model that incorporates fibril–matrix interaction and a fibril–fibril interaction defined by the contact area of the interposed matrix best matched published data for tendons with shallow cuts (less than 50% of the cross-sectional area). Application of this model to the case of many disrupted fibrils is based on linear superposition and is most successful when more fibrils are incorporated into the model. An equally distributed load sharing model for the fraction of remaining intact fibrils was inadequate in that it overestimates the strength for a cut less than half of the tendon's cross-sectional area. In a broader sense, results imply that shear-lag contributes significantly to the general mechanical behavior of tendons when axial loads are nonuniformly distributed over a cross section, although the predominant hierarchical level and microstructural mediators for this behavior require further inquiry.
Control of Discrete Time Chaotic Systems via Combination of Linear and Nonlinear Dynamic Programming
Authors: Merat Kaveh , Abbaszadeh Chekan Jafar , Salarieh Hassan , Alasty Aria
Published: May 2014

In this article by introducing and subsequently applying the Min–Max method, chaos has been suppressed in discrete time systems. By using this nonlinear technique, the chaotic behavior of Behrens–Feichtinger model is stabilized on its first and second-order unstable fixed points (UFP) in presence and absence of noise signal. In this step, a comparison has also been carried out among the proposed Min–Max controller and the Pyragas delayed feedback control method. Next, to reduce the computation required for controller design, the clustering method has been introduced as a quantization method in the Min–Max control approach. To improve the performance of the acquired controller through clustering method obtained with the Min–Max method, a linear optimal controller is also introduced and combined with the previously discussed nonlinear control law. The resultant combined controller has been applied on the Henon map and through comparison with both Pyragas controller, and the linear optimal controller alone, its advantages are discussed.
“Illuminating” reflection orders in architectural acoustics using SketchUp and light rendering
Authors: Carter J. Parkman
Published: May 2014

The conventional architecture workflow tends to—quite literally—“overlook” matters of sound, given that the modeling tools of architectural design are almost exclusively visual in nature. The modeling tools used by architectural acousticians, however, produce visual representations, which are, frankly, less than inspirational for the design process. This project develops a simple scheme to visualize acoustic reflection orders using light rendering in the freely available and widely used Trimble SketchUp 3D modeling software. In addition to allowing architectural designers to visualize acoustic reflections in a familiar modeling environment, this scheme also works easily with highly complex geometry. The technique and examples will be presented.
Traffic design for soundscape improvements
Authors: Genuit Klaus , Fiebig André
Published: May 2014

Different kinds of traffic contribute to urban acoustic environments and therefore have a major impact on urban soundscapes. The noise of traffic depends on several aspects such as traffic management, traffic routing, traffic composition, and infrastructure. In the past, any optimization of these aspects targets only on sound pressure level reduction, neglecting perceptional relevant phenomena. It is well known that the human hearing does not work like a simple sound level meter. Besides loudness, humans perceive psychoacoustic properties of noise and notice certain sound events and sources. Thus, any improvement of traffic noise must be guided by knowledge from psychoacoustics and cognition. To sustainably improve the appraisal of a soundscape, traffic must be deliberately designed. In different research projects, the psychoacoustic potential of traffic design was systematically investigated. For example, the perceptual difference between roundabouts and intersections with and without traffic lights was investigated, psychoacoustic requirements for the layout of road markings were studied, and the required penetration level of electric cars for a substantial noise reduction beyond sound pressure level considerations was an object of investigation. Options and possibilities of traffic design from a psychoacoustic perspective and their implications for urban planning will be presented.
Phased-array Doppler sonar measurements at the equator: Currents or swimming?
Authors: Smith Jerry A.
Published: May 2014

A 64-channel 200 kHz phased array Doppler sonar (PADS) was deployed on the Equator at 140 W, sampling a vertical slice of the ocean, from 9 m to 200 m depth by 100 degrees, twice per second. The instrument was operated for two nearly continuous time-series, Oct. 10–20 and Oct.24 to Nov. 3, 2012. While the PADS was operated off the Starboard side of the R/V Revelle, a “Fast-CTD” (FCTD) was simultaneously operated off the port stern, sampling to 250 m every 2.5 min. Headway was maintained at less than 1 m/s relative to the surface flow (which was small, in contrast to the ~1.5 m/s undercurrent at 100 to 130 m depth). Because of this slow headway, motile scatterers were able to develop ship-centric swimming patterns, particularly at night. This, in turn, introduced some subtly non-physical characteristics in the estimated vertical velocities in particular. Animations of the backscatter intensity reveal a variety of scales and speeds of the scatterers. Visual nighttime inspection revealed a preponderance of small squid (< 30 cm) with the occasional large predator passing rapidly through (not identified). In spite of this biological interference, reasonable profiles of horizontal velocity were produced via a simple de-spiking selector.
An information-rich learning environment for instruction in acoustics, part 3
Authors: Celmer Robert
Published: May 2014

The static written word has always had its limits when it comes to learning about sound. Much of the subject matter is dynamic, multifaceted, and of course, aural. This presentation will describe additional multimedia materials developed for in-class presentation and self-paced review exercises for acoustics instruction at the University of Hartford. Some of the materials were developed using certain authoring applications, draw and animation programs, sound manipulation software, as well as 3D-CAD and spectral analysis applets. Audio equipment used in class as well as acoustic treatments of the classroom/listening environment will be described. This approach to acoustic pedagogy will be discussed in the context of a student-centered learning environment. New and updated demonstrations of the materials for the instruction of acoustical concepts as well as case studies will be presented.
Fun with levitators
Authors: Holt R. Glynn
Published: May 2014

The acoustic radiation force is enjoying something of a comeback on the celebrity circuit these days. Current applications are seen, for example, in elasticity imaging in biomedical ultrasound, and separation technologies in the biomedical and petroleum arenas. But of course the application of radiation force to acoustic levitation has a long history, and in this talk, we will explore levitation to illustrate the principles of radiation force in standing waves with sample inclusions. With a little luck, both large bubbles in water and liquid drops in air will be demonstrated.
Bringing Matlab into the acoustics class
Authors: Vignola Joseph F. , Glean Aldo A. , Ryan Teresa J. , Turo Diego
Published: May 2014

The Catholic University of America has a history of graduate education in acoustics that ranges back to the 1930s. Many of the students served by CUA have been and continue to be working professionals in careers related to acoustics. Over time, we have observed that many of our students come to us having developed an impressive depth of knowledge in their specialty. However, some of these students have little of the formal acoustics training needed to provide broader context. This presentation will discuss teaching practices designed to serve this cohort as well as more traditional graduate students. We create an experiential learning environment that capitalizes on the fact that many simple but powerfully instructive measurements can be made with now ubiquitous items. All modern laptops have both speakers and a microphone. A laptop, coupled with a library of MATLAB code, gives students the opportunity to explore many important topics. This presentation includes examples from room acoustics, musical acoustics, and elastic wave propagation.
Resources for teaching near-field acoustical holography in advanced acoustics courses
Authors: Gee Kent L. , Neilsen Tracianne B. , Sommerfeldt Scott D.
Published: May 2014

The principles of planar near-field acoustical holography (NAH) can be used to motivate discussion of, or illustrate, physics of sound radiation or topics in signal processing. These include separable geometries, the Helmholtz equation, spatial Fourier transforms and the wavenumber domain, superposition of waves, the relationship between pressure and particle velocity, near and far fields, the radiation circle and evanescence, filtering, and signal-to-noise ratio. This paper describes the incorporation of NAH as part of a graduate-course unit on structural acoustics. Resources discussed, and which will be made available to educators, include a basic NAH processing script and example data collected by students using an automated positioning system in Brigham Young University's fully anechoic chamber.
Software usage for synthesized sound in acoustics education
Authors: Whiting Jennifer K. , Fortney Katherine H. , Neilsen Tracianne B. , Gee Kent L.
Published: May 2014

Musical acoustics engages students of many backgrounds when studying acoustics. Free software in the form of digital audio workstations can be used to provide students with a hands-on instruction to concepts of synthesis. Students can easily manipulate variables to add or detract from the realism of synthesized sound. This process of synthesizing sound provides a means for students to understand the concepts of additive and subtractive synthesis, attack and decay times, reverberation times, and filters. Application of free digital audio workstation software in an undergraduate class at Brigham Young University and in the recently revamped ASA Outreach workshop will be discussed.
Does fundamental frequency-segregation interact with dip listening or spatial unmasking?
Authors: Leclére Thibaud , Lavandier Mathieu , Deroche Mickael L.
Published: May 2014

Differences in fundamental frequency (F0) and location between a speech target and a masker as well as amplitude modulations in the masker are helpful cues to improve speech intelligibility in cocktail party situations. Each cue has been thoroughly investigated independently in many studies, but it remains unclear whether they interact with each other. Experiment 1 examined potential interactions between F0-segregation and dip listening while experiment 2 examined interactions between F0-segregation and spatial unmasking. Speech reception thresholds were measured for a monotonized or an intonated voice against eight types of harmonic complex interferers. In experiment 1, the eight interferers varied in F0 contour (monotonized or intonated), mean F0 (0 or 3 semitones above the target) and broadband temporal envelope (stationary or 1-voice modulated). In experiment 2, interferers varied in F0 contour, mean F0 and spatial location (colocated or separated from the target). Thirty-two listeners participated in each experiment. The results will be presented and discussed.
Speech intelligibility and masking release using temporal fine structure and recovered envelope cues for normal-hearing and hearing-impaired listeners
Authors: Leger Agnes C. , Reed Charlotte M. , Desloge Joseph G. , Swaminathan Jayaganesh , Braida Louis D.
Published: May 2014

Consonant-identification ability was examined in normal-hearing (NH) and hearing-impaired (HI) listeners in the presence of continuous and 10-Hz square-wave interrupted speech-shaped noise. The speech stimuli (16 consonants in a-C-a syllables) were processed to present envelope (ENV) cues, temporal fine-structure cues (TFS), or envelope cues recovered from TFS speech (RENV). ENV- and TFS-speech was generated by extracting the ENV or TFS component of the unprocessed speech in N adjacent bands (N = 40 for ENV-speech, N = 1 or 4 for TFS-speech; range = 80–8020 Hz). RENV-speech was generated by extracting the ENV component of both types of TFS-speech in 40 adjacent bands. NH listeners were tested at an SNR of −10 dB and individual HI listeners were tested with SNR in the range of −6 to + 5 dB. These values of SNR yielded consonant-identification scores of roughly 50%-correct for intact speech in continuous noise for each listener. HI listeners had poorer speech scores than NH listeners. For both groups, scores with TFS- and RENV-speech were very similar. Scores were higher in interrupted noise than in continuous noise (indicating substantial release from masking), except for unprocessed- and ENV-speech for HI listeners. Audibility, frequency selectivity, and forward masking were estimated for each listener and compared with speech identification.
Influence of context on the relative pitch dominance of individual harmonics
Authors: Gockel Hedwig E. , Alsindi Sami , Hardy Charles , Carlyon Robert P.
Published: May 2014

There is evidence that the contribution of a given harmonic in a complex tone to residue pitch is influenced by the accuracy with which the frequency of that harmonic is encoded. We investigated whether listeners adjust the weights assigned to individual harmonics based on acquired knowledge of the reliability of the frequency estimates of those harmonics. In a two-interval forced-choice task, seven listeners indicated which of two 12-harmonic complex tones had the higher overall pitch. In context trials (60% of all trials), the fundamental frequency (F0) was 200 Hz in one interval and 200+ΔF0 Hz in the other. In different blocks, either the third or the fourth harmonic, plus (always) the seventh, ninth, and 12th harmonics were replaced by narrowband noises that were identical in the two intervals. Feedback was provided. In test trials (40% of all trials), the fundamental frequency was 200+ΔF0/2 Hz in both intervals and either the third or the fourth harmonic was shifted slightly up or down in frequency. There were no narrowband noises. Feedback was not provided. The results showed that substitution of a harmonic by noise in context trials significantly reduced the contribution of that harmonic to pitch judgments in the test trials.
Discrete and continuous auditory feedback based on pitch and spatial lateralization for human-machine-interface control
Authors: Favrot Sylvain , Michener Carolyn M. , Stepp Cara E.
Published: May 2014

The purpose of this study was to investigate auditory-motor learning via discrete and continuous auditory feedback using pitch and spatial lateralization. Sixteen subjects used facial surface electromyography (sEMG) to control a human-machine-interface (HMI). The output of the HMI was a lateralized harmonic tone. The fundamental frequency and lateralization (left-right ear) changed with the sum and the difference of the bilateral muscle signals. For eight participants, these changes were continuous, whereas the other eight participants received discrete feedback, in which the frequency of the tone was one of nine possible semitones (from midi note #64 to #75) and the lateralization was either left, center or right. Participants trained over three days. A mixed-models analysis of variance showed a significant effect of learning over sessions and a trend for increased performance for the group utilizing discrete feedback. Overall, information transfer rates using this purely auditory feedback averaged 38.5 bit/min by day 3, which is similar to results from similar systems utilizing visual feedback. These results show that with minimal training, auditory feedback can provide usable HMI control.
Modeling temporal effects in two-tone suppression
Authors: Hegland Erica L. , Strickland Elizabeth A.
Published: May 2014

The medial olivocochlear reflex (MOCR) reduces the gain of the active process in the cochlea. Both physiological and psychoacoustical data support the hypothesis that the MOCR may improve the response to a tone in noise. This is generally interpreted as resulting from a decrease in the response to the noise. However, elicitation of the MOCR may also reduce suppression, an instantaneous cochlear gain reduction that is a by-product of the cochlear active process. There is only limited physiological and psychoacoustic data on the effect of the MOCR on suppression. Recently, the time-course of the MOCR has been integrated into a well-established computational auditory nerve model [Smalt et al., J. Assoc. Res. Otolaryngol. (2013)]. The purpose of this study is to use the auditory nerve model to systematically examine suppression and the effects of the MOCR at the level of the basilar membrane and the auditory nerve. These results will provide more understanding on the interaction of these two types of gain reduction and how they relate to speech understanding in noise. [Research supported by NIH(NIDCD) R01 DC008327 and T32 DC00030.]
Modeling speech intelligibility in distortion conditions using a speech-based speech transmission index
Authors: Yu Gongqiang , Brammer Anthony J. , Bernstein Eric R.
Published: May 2014

A modified objective model expanding on the speech-based speech transmission index is proposed to predict speech intelligibility under various conditions of nonlinear distortion. The proposed model computes values over a time window by analyzing the signal to noise ratio and the modulation transfer function between the input and output of a transmission channel. The channel is divided into frequency bands with ranges compatible with critical bands. The cross covariance among adjacent frequency bands is also considered. The index is obtained by averaging the calculated values of these time windows. The proposed model is evaluated with subjective measurement of word intelligibility scores using the modified rhythm test with non-linear distortions of phase jitter and clipping introduced into the speech material presented to subjects. The results demonstrate that high correlations between the indices of the proposed model and the intelligibility scores are maintained for these distortions.
Establishing a clinical measure of spectral-ripple discrimination
Authors: Molis Michelle R. , Gilbert Rachael , Gallun Frederick J.
Published: May 2014

Spectral-ripple discrimination thresholds have been used effectively to assess frequency-resolving power in cochlear implant users. To improve potential clinical utility as a reliable and time-efficient measure of auditory bandwidth for listeners with acoustic hearing, possible confounds and limitations of the method must be addressed. This study examined frequency specificity and the possibility of edge-listening with narrowband stimuli. An adaptive 4-IFC procedure was used to determine ripple discrimination thresholds for normally hearing (NH) and hearing-impaired (HI) listeners. Stimuli were broadband (100–5000 Hz), high pass (1000–5000 Hz), or low pass (100–1000 Hz) logarithmically scaled, sinusoidally modulated Gaussian noises. In some conditions, Gaussian flanking noise was introduced to eliminate potential edge-listening cues. As expected, discrimination thresholds were significantly reduced for the HI listeners. Additionally, results indicate that both NH and HI listeners are able to use edge cues to improve discrimination thresholds. The introduction of flanking noise significantly reduced thresholds, and this effect was largest for the high pass stimuli. These results can be used to evaluate the usefulness of this method as a rapid and efficient means of assessing the effective frequency bandwidth of listeners with acoustical hearing. [Work supported by NIH.]
Pitch shift of the residue and its brainstem electrophysiological correlates are explained by nonlinear oscillation
Authors: Lerud Karl D. , Kim Ji Chul , Large Edward W.
Published: May 2014

Data show that amplitude modulation is an important factor in the neural representation and perceived pitch of sound. However, sounds with identical Hilbert envelopes can elicit different pitches. Sounds with consecutive harmonics elicit a pitch at the difference frequency of the harmonics. If this complex is shifted up or down, the amplitude envelope stays the same, but the perceived pitch moves in the direction of the shift; thus the fine structure contributes to its perceived pitch. Physiologically, auditory nerve spike timing data have shown that fine structure is preserved during mechanical to neural transduction, and brainstem EEG experiments in humans show a unique and consistent frequency-following response (FFR) associated with pitch-shifted stimuli. Here, we model the FFR with canonical networks of nonlinear oscillators representing the cochlea, cochlear nucleus, and lateral lemniscus. Dynamical analysis reveals a resonance at the frequency of the perceived pitch that is rooted in the fine structure-locked portion of the response. We show that these responses are natural outcomes of an intrinsically nonlinear system. Our results provide good evidence for highly nonlinear auditory brainstem processing, and suggest that these nonlinearities are essential for the perception of pitch.
Wavenumber analysis of interface wave characteristics using elastic parabolic equation solutions
Authors: Frank Scott D. , Collis Jon M. , Odom Robert I.
Published: May 2014

Interface waves that travel along the ocean bottom are known as Scholte waves and can contribute to the deep ocean acoustic field, even at depths below the ray-theoretical turning point. Scholte waves spread by the inverse of the square root of range and propagate greater distances along the ocean floor than ocean acoustic energy. Elastic parabolic equation solutions are effective for analysis of Scholte wave behavior with respect to environmental parameters since these waves represent interactions between dilatational and rotational elastic waves resulting from elastic boundary conditions. Generation of interface waves by water column and buried seismic sources will be demonstrated. Hankel transforms of calculated acoustic pressure will be used to evaluate impact of elastic parameters on interface wave amplitudes and ducting effects in elastic sediment layers. The effect of large-scale bathymetry on interface wave propagation will also be investigated. [Work supported by ONR.]