bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstinence‐Related Word Associations and Definitions of Abstinence and Virginity Among Missouri High School Freshmen
Authors: Wilson Kelly L. , Smith Matthew Lee , Menn Mindy
Published: October 2013

BACKGROUND

The ways in which adolescents define and view sex, abstinence, and virginity impact the efforts of sexuality educators and sexual health professionals. This study examined terminology used by nonsexually active high school students to define abstinence and virginity and identified words students associate with these terms. Purposes included (1) describing words/phrases associated with abstinence; (2) describing phrases for “being abstinent until marriage” and “being a virgin;” (3) assessing concordance between word dyads associated with abstinence; and (4) assessing concordance between phrases defining “abstinent until marriage” and “a virgin.”

METHODS

In this study, 216 freshmen provided information about beliefs, behaviors, and perceptions. Pearson chi‐square tests and Wilcoxon sign‐rank tests assessed sex‐based differences, definitions, and levels of concordance were conducted.

RESULTS

Girls' friends took an abstinence pledge (p = .004) and their parents (p = .025) and best friends (p < .001) think they should abstain. Male counterparts reported being dissatisfied with current sex status (p = .002) and high acceptance of sex before marriage (p = .011). Boys were more likely to endorse “negative” words than girls.

CONCLUSIONS

Professionals need to use relevant materials incorporating terminology that resonates with adolescents and programs that engage coherent participant discussions.
Waist‐to‐Height Ratio and Body Mass Index as Indicators of Cardiovascular Risk in Youth
Authors: Keefer Daniel J. , Caputo Jennifer L. , Tseh Wayland
Published: October 2013

BACKGROUND

The purpose of this investigation was to determine if waist‐to‐height ratio (WHTR) or body mass index (BMI) is the better indicator of cardiovascular disease risk in children and adolescents of varying ages.

METHODS

Data from children and adolescents (N = 2300) who were part of the 2003‐2004 National Health and Nutrition Examination Survey (NHANES) were analyzed. Chi‐square analyses (2 × 2) were used to compare risk levels of WHTR (>0.50) and BMI (>85th percentile) to systolic blood pressure (SBP) (>90th percentile) as well as total cholesterol (TC) (>200 mg.dL−1) for the entire cohort and specified age groups.

RESULTS

Significant relationships were detected between SBP and WHTR and BMI, respectively, for the entire cohort as well as the 2 oldest subsamples. A significant association was also noted for both WHTR and BMI to TC for the entire sample and the eldest age group.

CONCLUSIONS

A significant association was observed between indicators of cardiovascular health risk and both WHTR and BMI in the entire NHANES cohort of boys and girls as well as in the older age groups. The younger groups of participants did not display a notable link between these cardiovascular indicators and WHTR or BMI.
Evaluation of School Tobacco‐Free Policies in a Rural Northern Plains State
Authors: Fahrenwald Nancy L. , Kerkvliet Jennifer L. , Carson Paula , Lammers Cristina , Melstad Sandra , Dugstad DeEtta , McCord Jim
Published: October 2013

BACKGROUND

The Centers for Disease Control and Prevention (CDC) has called for tobacco‐free school (TFS) policies. In South Dakota (SD), a rural state with a large American Indian population, collaboration between state agencies focused on development and dissemination of a model TFS policy in 2008. This study explored the current status of TFS policies in statewide SD school districts.

METHODS

Tobacco policies were requested from all SD school district administrators. A 26‐point checklist based on CDC TFS policy guidelines was used to evaluate policies. Follow‐up interviews were conducted with selected superintendents.

RESULTS

Policies were received from 144 of 217 districts (66% response). Participation was higher for public districts than tribal/Bureau of Indian Education (BIE) districts and nonpublic districts. The overall mean policy score was 11.6 (SD 5.1). Public school districts had the highest mean (12.3) followed by nonpublic (8.9) and tribal/BIE (7.5). In a subset of districts with a large American Indian population (>30%), policy scores were lower for those located on reservation or tribal lands compared with other locations. Barriers to policy development were identified as time and staff expertise.

CONCLUSIONS

There is a need to improve statewide TFS policies. A district report card with recommendations for improvement and a resource guide were developed and disseminated.
Moving Corporate Boundaries: Consequences for Innovative Redesign
Authors: Gadde Lars‐Erik
Published: October 2013

The latest century has witnessed two major transformations of the business landscape through which the boundaries of firms were modified substantially. The first was the establishment of the large‐scale integrated hierarchies, like the Ford Motor Company, in the beginning of the 20th century. The second was the disintegration of these hierarchies at the end of the same century. In both cases, the objective of the boundary movement was to improve the opportunities for innovative redesign. Because the strategic approaches to achieve this objective were quite different, the interplay between innovative redesign and changes of the boundaries of firms deserves further exploration. This article is based empirically on previous research on these two types of transformations. The information from these studies is used to formulate seven propositions concerning the interplay between innovative redesign and corporate boundaries. Three main findings spring from this study. First, the boundaries of firms are multifaceted. In addition to the ownership boundary, it is demonstrated that influence boundaries and awareness boundaries are central in innovative redesign. Second, corporate boundaries are dynamic. The study shows that sometimes they function as buffers in relation to other firms, while in other situations, they serve as bridges. Third, for the individual firm's boundary setting, two issues appear to be critical: one concerns the trade‐off between specialization and integration, and the other relates to the interaction between the internal capabilities of the firm and those that are accessible from business partners.
Seronegative hepatitis C virus infection in patients with lymphoproliferative disorders
Authors: Kisiel E. , Radkowski M. , Pawelczyk A. , Horban A. , Stanczak J. , Bukowska‐Ośko I. , Caraballo Cortes K. , Kaźmierczak J. , Popiel M. , Laskus T.
Published: October 2013

It has been reported that hepatitis C virus (HCV) RNA may be present in serum and/or lymphoid cells in the absence of specific circulating antibodies. The current study analysed seronegative HCV infection in patients with lymphoproliferative disorders. We studied 77 anti‐HCV‐negative patients (45 male and 32 female, mean age 54.8 ± 14.2 years) with various lymphoproliferative disorders. HCV‐RNA was detected by RT‐PCR in plasma, peripheral blood mononuclear cells (PBMC) and bone marrow. Furthermore, the presence of viral nonstructural protein 3 (NS3) was determined in PBMC and bone marrow by immunostaining. HCV‐RNA was detectable in at least one compartment in 27 (35.1%) patients. Viral RNA was found in bone marrow in 22 patients (28.6%), in PBMC in 13 (16.9%) and in plasma in 10 (13%) patients. In nine patients, evidence of infection was confined to the bone marrow compartment. Viral load in HCV‐RNA‐positive plasma ranged from 15 to 1.17 × 103 IU/mL. NS3 was detected in all but two HCV‐RNA‐positive bone marrow samples and in all but one HCV‐RNA‐positive PBMC samples. All 27 HCV‐RNA‐positive patients remained anti‐HCV‐negative when tested again after 6–12 months, but only four remained HCV‐RNA positive. In conclusion, among patients with lymphoproliferative disorders, HCV can be present in plasma, PBMC and bone marrow despite the lack of circulating specific antibodies. Further studies are required to analyse the phenomenon of seronegative infection and to determine whether such patients are infectious.
Liberal Rights versus Islamic Law? The Construction of a Binary in Malaysian Politics
Authors: Moustafa Tamir
Published: October 2013

Why are liberal rights and Islamic law understood in binary and exclusivist terms at some moments, but not others? In this study, I trace when, why, and how an Islamic law versus liberal rights binary emerged in Malaysian political discourse and popular legal consciousness. I find that Malaysian legal institutions were hardwired to produce vexing legal questions, which competing groups of activists transformed into compelling narratives of injustice. By tracing the development of this spectacle in the courtroom and beyond, I show how the dueling binaries of liberal rights versus Islamic law, individual rights versus collective rights, and secularism versus religion were contingent on institutional design and political agency, rather than irreconcilable tensions between liberal rights and the Islamic legal tradition in some intrinsic sense. More broadly, the research contributes to our understanding of how popular legal consciousness is shaped by legal mobilization and countermobilization beyond the court of law.
Morphological characteristics and developmental changes of the ovary in the tick Haemaphysalis longicornis Neumann
Authors: YANG X. L. , YU Z. J. , GAO Z. H. , YANG X. H. , LIU J. Z.
Published: October 2013

Haemaphysalis longicornis (Ixodida: Ixodidae) is an important vector of transovarially transmitted parasites of the genus Babesia (Piroplasmida: Babesiidae). In the present study, we investigated the morphological characteristics and developmental changes of the ovary of H. longicornis. We show that the ovary of H. longicornis has a single tubular structure and is surrounded by a tunica propria. There is a longitudinal groove along one side of the ovary. During feeding and after engorgement, great changes can be observed in the ovary of H. longicornis and two rapid growth phases can be detected. The number of major protein bands of the ovary is significantly increased from day 3 of feeding and reaches a maximum on the day of engorgement. Therefore, the great diversity of proteins in the ovaries of H. longicornis can facilitate the identification of new targets for vaccine development.
Anti‐Laminin‐332 Mucous Membrane Pemphigoid in a 9‐Year Old Girl
Authors: Kahn Estelle , Spence Shishido Allyson , Yancey Kim B. , Lawley Leslie P.
Published: October 2013

Mucous membrane pemphigoid (MMP), an autoimmune subepithelial blistering disease that predominantly affects the mucous membranes, is usually diagnosed in elderly adults. Early diagnosis of MMP is crucial because it tends to run a chronic and progressive course with the potential for devastating scarring of the mucous membranes that may lead to blindness and airway compromise. A subtype of MMP, anti‐laminin‐332 MMP, is a rare blistering disorder in which autoantibodies are directed against laminin‐332 (formerly epiligrin), a structural protein of the epidermal basement membrane. Herein we report what we believe to be the youngest patient diagnosed with anti‐laminin‐332 MMP, a 9‐year‐old girl with disease affecting only the oral, pharyngeal, and laryngeal mucosa, with no skin involvement.
Childhood Lichen Planus Pemphigoides: Report of Two Cases Treated Successfully with Systemic Glucocorticoids and Dapsone
Authors: Goldscheider Ilana , Herzinger Thomas , Varga Rita , Eming Rüdiger , Ruzicka Thomas , Flaig Michael J. , Sárdy Miklós
Published: October 2013

We describe two boys, ages 8 and 7 years, who developed lichen planus pemphigoides. In one of the boys, a henna tattoo probably triggered the disease. Therapy with systemic glucocorticoids and dapsone was successful.
Comparing Costs and Risks of Retirement Plans for Sponsors
Authors: Pang Gaobo , Warshawsky Mark
Published: October 2013

This stochastic simulation analysis compares funding costs and volatilities for private sponsors of traditional defined benefit (DB), pension equity (PE), cash balance (CB), and defined contribution (DC) retirement plans. Plan provisions of equivalent benefit generosity in the different plan types are determined. The modeling includes current funding requirements and practices as well as a comprehensive set of uncertainties in asset and labor markets. The results show that costs and risks for sponsors vary significantly with plan types, investment and funding strategies, and participant demographics. The hybrid PE and CB plans exhibit characteristics of cost efficiency, as in the DB plan, and risk reduction, as in the DC plan, for plan sponsors under conventional investment strategies. These features are more saliently observed in the CB plan, but it is also more difficult to implement effective asset–liability management strategies for it.
A Review of Catastrophic Risks for Life Insurers
Authors: Huynh Alex , Bruhn Aaron , Browne Bridget
Published: October 2013

Catastrophic mortality events are characterized by a sudden and concentrated increase in mortality and as such present a major risk to life insurers. Such events include pandemics, war, natural disasters, terrorist attacks, and industrial, transport, and other accidents. Of these, pandemics arising from influenza are considered the most significant threat to the life insurance industry due to their capacity to cause a major increase in claims. We review the features and mortality implications of an influenza pandemic for life insurers, and describe a range of other risks that are likely to emerge as well.
Actuarial Science Summer Program for Women and Minorities
Authors: Gardner Lisa , Santos Christian Roldán , White Toby
Published: October 2013

Drake University offered a 5‐day program focusing on the recruitment of women and minorities into actuarial science studies. A few universities offer actuarial science summer camps targeting high school students. Participants in this camp, however, came exclusively from community colleges. In this article, we provide an overview of the camp's activities, structure, and outcomes. We present a longitudinal analysis of student feedback, reflecting results from one survey administered before the camp began and another distributed very near the camp's end. Our results indicate the camp succeeded on many counts.
Strain Localisation in iPP/MWCNT Nanocomposites Using Digital Image Correlation
Authors: Ivanov E. , Ienny P. , Leger R. , Caro‐Bretelle A. S. , Kotsilkova R.
Published: October 2013

Polypropylene/multiwall carbon nanotube nanocomposites with different rates of weight incorporation (0–1%) were prepared by melt compounding and cast extrusion. The effect of maleic anhydride (5 wt%) grafted on polypropylene is studied through mechanical tests at different scales and morphological observations. In particular, the micromechanism of deformation was investigated through instrumented tensile experiments (at a macro and micro scales) using of a non‐contact method known as digital image correlation. The objective of this paper is first to characterise global behaviour (Young modulus, tensile strength, and ultimate properties) and second to go further in local analysis. In particular, optical instrumentation enables estimation of strain profile distribution onto the sample in a constricted area. Statistical parameters extracted from these local profiles are promising tools to enhance mechanical properties in link with microstructural composition. Tensile tests confirm composite reinforcement at a low level of nanocomposite incorporation, and local analysis enables quantitative measurements of adding maleic anhydride in formulations. The results reveal that addition of maleic anhydride delays strain localisation in the necked area.
A multi‐colour/multi‐affinity marker set to visualize phosphoinositide dynamics in Arabidopsis
Authors: Simon Mathilde Laetitia Audrey , Platre Matthieu Pierre , Assil Sonia , van Wijk Ringo , Chen William Yawei , Chory Joanne , Dreux Marlène , Munnik Teun , Jaillais Yvon
Published: October 2013

Phosphatidylinositolphosphates (PIPs) are phospholipids that contain a phosphorylated inositol head group. PIPs represent a minor fraction of total phospholipids, but are involved in many regulatory processes, such as cell signalling and intracellular trafficking. Membrane compartments are enriched or depleted in specific PIPs, providing a unique composition for these compartments and contributing to their identity. The precise subcellular localization and dynamics of most PIP species is not fully understood in plants. Here, we designed genetically encoded biosensors with distinct relative affinities and expressed them stably in Arabidopsis thaliana. Analysis of this multi‐affinity ‘PIPline’ marker set revealed previously unrecognized localization of various PIPs in root epidermis. Notably, we found that PI(4,5)P2 is able to localize PIP2‐interacting protein domains to the plasma membrane in non‐stressed root epidermal cells. Our analysis further revealed that there is a gradient of PI4P, with the highest concentration at the plasma membrane, intermediate concentration in post‐Golgi/endosomal compartments, and the lowest concentration in the Golgi. Finally, we also found a similar gradient of PI3P from high in late endosomes to low in the tonoplast. Our library extends the range of available PIP biosensors, and will allow rapid progress in our understanding of PIP dynamics in plants.
Exploring the Arabidopsis sulfur metabolome
Authors: Gläser Katharina , Kanawati Basem , Kubo Tobias , Schmitt‐Kopplin Philippe , Grill Erwin
Published: October 2013

Sulfur plays a crucial role in protein structure and function, redox status and plant biotic stress responses. However, our understanding of sulfur metabolism is limited to identified pathways. In this study, we used a high‐resolution Fourier transform mass spectrometric approach in combination with stable isotope labeling to describe the sulfur metabolome of Arabidopsis thaliana. Databases contain roughly 300 sulfur compounds assigned to Arabidopsis. In comparative analyses, we showed that the overlap of the expected sulfur metabolome and the mass spectrometric data was surprisingly low, and we were able to assign only 37 of the 300 predicted compounds. By contrast, we identified approximately 140 sulfur metabolites that have not been assigned to the databases to date. We used our method to characterize the γ‐glutamyl transferase mutant ggt4‐1, which is involved in the vacuolar breakdown of glutathione conjugates in detoxification reactions. Although xenobiotic substrates are well known, only a few endogenous substrates have been described. Among the specifically altered sulfur‐containing masses in the ggt4‐1 mutant, we characterized one endogenous glutathione conjugate and a number of further candidates for endogenous substrates. The small percentage of predicted compounds and the high proportion of unassigned sulfur compounds identified in this study emphasize the need to re‐evaluate our understanding of the sulfur metabolome.
Epidermal identity is maintained by cell–cell communication via a universally active feedback loop in Arabidopsis thaliana
Authors: San‐Bento Rita , Farcot Etienne , Galletti Roberta , Creff Audrey , Ingram Gwyneth
Published: October 2013

The transcription factors ARABIDOPSIS THALIANA MERISTEM L1 (ATML1) and PROTODERMAL FACTOR2 (PDF2) are indispensable for epidermal cell‐fate specification in Arabidopsis embryos. However, the mechanisms of regulation of these genes, particularly their relationship with cell–cell signalling pathways, although the subject of considerable speculation, remain unclear. Here we demonstrate that the receptor kinase ARABIDOPSIS CRINKLY4 (ACR4) positively affects the expression of ATML1 and PDF2 in seedlings. In contrast, ATML1‐ and PDF2‐containing complexes directly and negatively affect both their own expression and that of ACR4. By modelling the resulting feedback loop, we demonstrate a network structure that is capable of maintaining robust epidermal cell identity post‐germination. We show that a second seed‐specific signalling pathway involving the subtilase ABNORMAL LEAFSHAPE1 (ALE1) and the receptor kinases GASSHO1 (GSO1) and GASSHO2 (GSO2) acts in parallel to the epidermal loop to control embryonic surface formation via an ATML1/PDF2‐independent pathway. Genetic interactions between components of this linear pathway and the epidermal loop suggest that an intact embryo surface is necessary for initiation and/or stabilization of the epidermal loop, specifically during early embryogenesis.
Sticky lives: slugs, detachment and more‐than‐human ethics in the garden
Authors: Ginn Franklin
Published: October 2013

In response to the pressing need to re‐constitute the ways we live with non‐humans, more‐than‐human geography's distinctive contribution has been to describe an ethics based not on ‘certain subjects’ but on the relational entanglement of life: to show that ‘we’ are connected and thus invited to care. This paper aims to suggest, however, that this relational diagnostic obscures as much as it reveals and that detachment, as much as relation, provides an everyday ethic that can accommodate more‐than‐human difference. I do this by analysing how life is stuck together and pulled apart in the British domestic garden, drawing on life history interviews and ‘show me your garden’ walking tours with experienced gardeners. The article is aligned with a widening bestiary of companion species in geography, and considers the appearances and disappearances of a domestic monster: the slug. Therefore in contrast to existing literature the paper explores gardening's darker aspects. First, I describe how slugs and gardeners are ‘sticky’: joined together by shared histories, curiosity and disgust. The paper then shifts to examine how gardeners practice detachment: distancing themselves from the act of killing slugs but yet avowing the violence of their actions; acknowledging the limits of their capacities to bend space to their will and imagination; recognising the vulnerability of slugs, and being transformed by that recognition. The analysis shows first, that the emphasis on gathering together and relationality obscures what lies outside relations, and second how detachment emerges not as the negation, but as an enabling constituent of more‐than‐human ethics. In conclusion the paper argues for looser mappings of relationality and ethics that attend more fully to the distance between species.
Review of Waste Heat Recovery Mechanisms for Internal Combustion Engines
Authors: Armstead John R. , Miers Scott A.
Published: October 2013

The demand for more fuel efficient vehicles has been growing steadily and will only continue to increase given the volatility in the commodities market for petroleum resources. The internal combustion (IC) engine utilizes approximately one third of the chemical energy released during combustion. The remaining two-thirds are rejected from the engine via the cooling and exhaust systems. Significant improvements in fuel conversion efficiency are possible through the capture and conversion of these waste energy streams. Promising waste heat recovery (WHR) techniques include turbocharging, turbo compounding, Rankine engine compounding, and thermoelectric (TE) generators. These techniques have shown increases in engine thermal efficiencies that range from 2% to 20%, depending on system design, quality of energy recovery, component efficiency, and implementation. The purpose of this paper is to provide a broad review of the advancements in the waste heat recovery methods; thermoelectric generators (TEG) and Rankine cycles for electricity generation, which have occurred over the past 10 yr as these two techniques have been at the forefront of current research for their untapped potential. The various mechanisms and techniques, including thermodynamic analysis, employed in the design of a waste heat recovery system are discussed.
Condensation Heat Transfer in Ultracompact Minichannel Heat Exchangers
Authors: Zhang Zhen , Peles Yoav , Jensen Michael K.
Published: October 2013

To improve condensation heat transfer performance in a variety of systems, reduced channel sizes are used. However, few studies have been performed on complete heat exchangers. Hence, condensation heat transfer coefficients were studied experimentally in two ultracompact heat exchangers with a hydraulic diameter of 133 μm using steam as the working fluid. Effects of mass flux, average vapor quality, saturation pressure, and heat exchanger size were examined. The condensation heat transfer coefficients showed strong influence of mass flux and quality. However, the effects of saturation pressure and heat exchange size were not significant. Three conventional and three mini/microscale correlations were compared with the experimental data. The conventional and mini/microscale correlations developed for annular flow overpredict the data significantly. The Soliman correlation developed for mist flow showed the best agreement with the data.
Designing for speech privacy in offices
Authors: Roy Kenneth P.
Published: October 2013

Speech privacy is an important component of the building interior environment, as it affects the satisfaction and performance of the occupants and thus their productivity. Privacy, both in terms of the confidentiality of conversations and relative to distractions and annoyance, needs to be considered. Field measurements of interzone attenuation, S/N ratio, and privacy calculations will be presented for various open and closed office designs from evaluations in several buildings. Field sound measurement techniques, and electronic masking system design and tuning will be discussed.
Meeting space acoustics
Authors: Tan Paul L.
Published: October 2013

A general synopsis of acoustic requirements in large dedicated, or multiuse spaces in entertainment, such as casinos, hotels, and themed restaurants is presented. This paper will explore various acoustical performance criteria such as building system noise and vibration, space volume, architectural geometry, sound isolation, and factors influencing speech and music intelligibility, such as reverberation, echoes, etc., Also included in this exploration will be the integration of modern 21st century multimedia and telecommunications technology.
Acoustic competition in the gulf toadfish Opsanus beta
Authors: Fine Michael L. , Thorson Robert F.
Published: October 2013

Nesting male Opsanus beta produce boatwhistle advertisement calls and agonistic grunt calls. The grunt is a short-duration pulsatile call, and the boatwhistle is a complex call typically consisting of zero to three introductory grunts, a long tonal boop note, and zero to three shorter boops. The beginning of the boop note is also gruntlike. Anomalous boatwhistles contain a short duration grunt embedded in the tonal portion of the boop or between an introductory grunt and the boop. Embedded grunts have sound pressure levels and frequency spectra that correspond with those of recognized neighbors, suggesting that one fish is grunting during another’s call, a phenomenon here termed acoustic tagging. Snaps of nearby pistol shrimp may also be tagged, and chains of tags involving more than two fish occur. The stimulus to tag is a relatively intense sound with a rapid rise time, and tags are generally produced within 100 ms of a trigger stimulus. Time between the trigger and the tag decreases with increased trigger amplitude. Tagging is distinct from increased calling in response to natural calls or stimulatory playbacks since calls rarely overlap other calls or playbacks. Tagging is not generally reciprocal between fish suggesting parallels to dominance displays.
Snapping shrimps: The bane of bioacoustics monitoring of coral reefs
Authors: Au Whitlow W. L.
Published: October 2013

Snapping shrimps are the major source of biological noise in shallow bays, harbors, inlets, and coral reefs in temperate and tropical waters. The sounds are impulsive with a very broad spectrum spanning from several hundred Hz to over 200 kHz. Peak frequencies are typically between 1–10 kHz with a very slow drop-off in energy with increasing frequency. At 200 kHz, the intensity of the sound may be only 20 dB below the intensity at the peak frequency. The peak-to-peak source level can be higher than approximately 189 dB re 1 mPa. When a shrimp rapidly closes its snapper claw, a high-velocity water jet that has speed exceeding cavitation conditions is produced. The sound is the result of a cavitating bubble collapsing. In a body of water, the overall level of snapping shrimp sounds can be as high as 20 dB above the noise level typical of sea state 6. The noise is present continuously, with little diurnal and seasonal variations and its broad frequency extent make it extremely difficult to filter this noise. Therefore, snapping shrimp sounds can severely limit the use of underwater bioacoustic monitoring in a coral reef environment.
Choruses from fishes in the Great Barrier Reef
Authors: McCauley Robert D. , Cato Douglas H.
Published: October 2013

Sounds from fish and invertebrates are a major component of the ambient sea noise around Australia, particularly within the Great Barrier Reef. Choruses from large numbers of calling animals are common and cause large variations in noise level. Long term statistics from the central Great Barrier Reef showed fish calling was a major contributor, both as continuous choruses and as individual calls repeated frequently. Four calling types predominated, with each displaying unique call characteristics and calling patterns through time and space. Durations varied from less than 10 ms to several seconds long, and comprised from one to nearly 40 pulses. These sounds were most common during the Australian summer with one call type also displaying lunar trends. They all showed diurnal variation with the highest activity generally at night, but times of maximum calling rate for each source type differed, consistent with avoiding competition for sound space. The acoustical characteristics of the call types provided information on the fishes calling physiology and behavior. The structure of each pulse could be related to swimbladder mechanics, with swimbladders normally lightly damped. On some occasions, a call type attributed to nocturnal planktivorous fishes may have ensonified much of the Great Barrier Reef.
Ontogenetic development of mechanosensory ability of a pomacentrid coral fish, the red saddleback clownfish (Amphiprion ephippium)
Authors: Yan Hong , Simpson Steve , Wittenrich Matthew
Published: October 2013

Recent work on the settlement of coral reef fish suggests that ambient sound could be used as a cue for navigation by the pelagic larvas of reef fishes. Coral reef fish larvas made directional movements toward sound stimulus indicating they are capable of detecting and localizing sound. These findings suggest that some degrees of hearing abilities must have developed prior to settlement. We used embryos and newly hatched larvas of a clown fish (Amphiprion ephippium) to investigate the ontogenetic development of the auditory function of this fish. The heart beat rates of embryos and newly hatched larvas (up to 7 days after hatching) in response to various frequencies of sound were measured to indicate their reaction to mechanosensory stimuli. The auditory brainstem response (ABR) recording protocol was used to measure acoustically evoked potentials of Day-8 to Day-36 larvas. Preliminary findings indicate that both the embryos’ and larvas reaction to sound stimuli improved (both frequency range and sound pressure level) throughout the development. The electrophysiological observations on embryos and larvas of Amphiprion ephippium provide evidence to support the hypothesis that acoustic stimuli could be used as a cue for coral reef larval fish migration use. [Work supported by NIH, NOHR, IMLS, NERC, AIMS.]
Frequency-dependent attenuation in unconsolidated marine sediments
Authors: Richardson Michael D.
Published: October 2013

Wood and David Weston (1964) reported that in situ attenuation varied linearly with frequency (constant Q) over the frequency range 4 to 70 kHz in mud sediments from Emsworth Harbour, Hampshire UK. This linear frequency dependence seemed at odds with propagation models according to Wood and Weston. Since this pioneering work, actually conducted in 1951–52, numerous authors have measured attenuation in a variety of unconsolidated sediments and over a wide range of frequencies. Hamilton (1972, 1985), Kibblewhite (1989), and Bowles (1997) provide excellent compilations of frequency-dependent attenuation in unconsolidated sediments. Given the measurement difficulties, the wide variety of techniques used to measure attenuation, and changes in the nature of sediment at different spatial scales, the exact form of frequency dependence is still a widely debated issue. Recent measurements over the frequency range of 20–100 kHz in sandy sediments tend to support a linear dependency of attenuation with frequency, at least over this frequency range. [Work supported by ONR.]
Measuring acoustic backscattering of deepwater fish in situ using a manned submersible
Authors: Benoit-Bird Kelly , Au Whitlow , Kelley Christopher , Taylor Christopher
Published: October 2013

An outstanding problem in fisheries acoustics is the depth dependence of scattering characteristics, required for sonar surveys, of swimbladder-bearing fish. The swimbladder, which is the major source of acoustic reflectivity, may become compressed due to increasing pressure with water depth, changing backscatter characteristics. To address this, echoes from deepwater snappers were obtained from a manned submersible using broadband sonar. A low-light camera mounted next to the sonar transducer permitted simultaneous identification of species, fish size, and orientation. Data were compared to echoes from captured fish measured at the surface. The relationship between fish length and in situ target strength showed no difference from the relationship measured at the surface. No differences in the species-specific temporal echo characteristics were observed between surface and in situ measures. This indicates that the size and shape of the fish’s swimbladder are maintained both at the surface and at depths of up to 250 m.
Influence of fetch limited surface roughness on mid-to-high frequency acoustic propagation in shallow water
Authors: Heitsenrether Robert , Badiey Mohsen , Kirby James , Forsythe Steve
Published: October 2013

Surface waves are among several environmental parameters that can influence broadband mid-to-high frequency (1–18 kHz) acoustic wave propagation. Understanding the interaction of sound waves at a rough surface requires a detailed description of the ocean wave spectrum. In shallow water regions, due to proximity to land, surface waves are usually fetch and duration limited with reduced spectral level and higher frequency components. A model that approximates the wave spectra for a fetch limited sea has been combined with acoustic ray-based method for analysis of forward scattered acoustic signals in such a coastal environment. Numerical modeling is employed to investigate time-frequency-angle characteristics of ray paths reflected from a rough sea surface. Temporal variability of acoustic signal fluctuations has been examined as a function of varying sea surface. To validate this model, results are compared against a unique set of experimental data collected in a fetch limited region. The experimental design allowed an examination of time evolution of a single surface bounced ray path. Simultaneous wind speed and acoustic propagation measurements allowed correlation between the individual ray paths and the sea surface at varying sea state conditions. For low wind speed conditions, model results predict the temporal fluctuations of the measured acoustic signal propagation.
Comparative study of optical detection for scanning laser acoustic microscopy
Authors: Cywiak Moises , Wade Glen
Published: October 2013

Scanning laser acoustic microscopy (SLAM) provides a way of visualizing and measuring surface features of nanometric order by a combination of acoustical and optical means. The acousto-optical interface in SLAM is an acoustically transparent and optically reflecting surface embedded in the acoustic medium. Acoustical excitation causes a dynamic surface deformation which is picked up by a focused scanning laser beam which, after reflection, is modulated in its phase and angle of reflection. There are three basically different demodulation schemes reported in the literature: the knife-edge detector, the time-delay interferometric detector, and the reference-beam detector. (In addition, a new detector derived from the knife-edge detector, namely the pyramidal-mirror detector, is scheduled for separate treatment in this session.) This paper presents comparative studies of the above three basic methods of detection. The performance characteristics of each are analyzed in detail by a careful examination of the transfer function for each of the systems. Computer simulations for their operation provide a comprehensive picture of the strengths and weaknesses of each.
Increasing image resolution using the pyramidal detector
Authors: Isakson Steve , Sahagun Luis Roberto , Wade Glen
Published: October 2013

The knife-edge detector (KED) has been used in transverse wave, scanning laser acoustic microscopes (SLAM) successfully for many years. It possesses a good balance between spatial bandwidth, detector noise insensitivity, and detector grain stability. Many detectors have tried to increase the bandwidth to improve the image resolution, only to be difficult to use and susceptible to vibration and mechanical variations. The authors have invented and designed a pyramidal detector (PD) that combines the stability and noise insensitivity of the KED with a significantly improved bandwidth in both axes of the object plane. The detector uses the entire signal provided at the detector to increase the signal to noise ratio and significantly decrease the cover slip spatial frequencies that are difficult to detect. The increased bandwidth allows image resolution approaching what an ideal detector could achieve. Additionally, unlike the KED, the PD spatial bandwidth is approximately isotropic to waves traveling in the cover slip. Increased spatial resolution and uniformity result. This property is particularly useful for back-propagation in tomographic applications.
Shape optimization techniques for musical instrument design
Authors: Henrique Luis , Antunes Jose , Carvalho Joao S.
Published: October 2013

The design of musical instruments is still mostly based on empirical knowledge and costly experimentation. One interesting improvement is the shape optimization of resonating components, given a number of constraints (allowed parameter ranges, shape smoothness, etc.), so that vibrations occur at specified modal frequencies. Each admissible geometrical configuration generates an error between computed eigenfrequencies and the target set. Typically, error surfaces present many local minima, corresponding to suboptimal designs. This difficulty can be overcome using global optimization techniques, such as simulated annealing. However these methods are greedy, concerning the number of function evaluations required. Thus, the computational effort can be unacceptable if complex problems, such as bell optimization, are tackled. Those issues are addressed in this paper, and a method for improving optimization procedures is proposed. Instead of using the local geometric parameters as searched variables, the system geometry is modeled in terms of truncated series of orthogonal space-funcitons, and optimization is performed on their amplitude coefficients. Fourier series and orthogonal polynomials are typical such functions. This technique reduces considerably the number of searched variables, and has a potential for significant computational savings in complex problems. It is illustrated by optimizing the shapes of both current and uncommon marimba bars.
Transverse and torsional modes of vibration of American organ reeds
Authors: Dirksen Blake M. , Cottingham James P.
Published: October 2013

A reed from an American reed organ consists of a brass tongue riveted to a frame with an opening just large enough for the reed to pass through during the course of its oscillation. To a first approximation, the reed tongue can be modeled as a cantilever beam of uniform cross section, and the mode frequencies of transverse and torsional modes can be calculated. The reeds used in this study differ from this simple model in several ways, including a nonuniform thickness along the reed length. In addition, the reed includes a curved spoon-like section at the tip of the reed tongue as well as an asymmetric twist at the tip. Transverse and torsional modes of vibration of a mechanically excited reed tongue have been studied using a proximity sensor (variable impedance transducer), a laser vibrometer, and a TV holography system. The motion of the air-driven reed has also been investigated. Although the motion of air-driven reed is dominated by the first transverse mode, some evidence of higher-order transverse modes and torsional modes has been observed. [Work supported by the NSF from REU Grant No. 0139096.]
The acoustics of the bagana
Authors: Weisser Stephanie , Demolin Didier
Published: October 2013

The bagana is a big Ethiopian lyre with ten strings. The instrument is found in the area of the Amhara, the culturally dominant tribe of Ethiopia. It is an intimate instrument, played only with the voice, for prayer and meditation. It can be tuned in two pentatonic scales, and can be plucked with the fingers, string by string or with a plectrum, all strings together. The box of the bagana is made of wood covered with leather, and the strings are made of gut. They are very thick and between them and the bridge, there are ten buzzers. Therefore, the bagana produces a very deep and buzzing sound. The paper will analyze the acoustical function of several parts of this instrument, e.g., the sound box and its crosslike hole at the back. The influence of the buzzers on the fundamental frequency, the spectrum, the duration, and the intensity of the signal will be closely examined. The role of the five unused strings (the ‘‘rest’’ strings) will also be examined.
Investigation of the acoustic parameters that influence traffic noise
Authors: Armas Alejandro A. , Iasi Federico M.
Published: October 2013

Here, we analyze the behavior of the acoustic parameters Leq, L1, L10, L50, L90, L99, Lmin, and Lmax of vehicular noise, which were measured in controlled laboratory conditions, for various traffic noise simulations. For that, sound recordings were created of equal duration but different composition, based on real recordings of the passage of different types of vehicles (cars, motorbikes, trucks, and buses) and using pink noise as background noise. This study is based on the necessity of finding the most appropriate parameters for the characterization of the traffic noise in the cities. The study began with the test of a measurement methodology that uses the equivalent continuous sound level, the main acoustical parameter applied in the city of La Plata, Argentina. However, Leq was shown insufficient and inadequate in certain situations, especially those that didn’t exhibit intense traffic noise, as found in certain residential areas. (To be presented in Spanish.)
Military aircraft noise and nonlinear acoustics
Authors: Sparrow Victor W. , Gee Kent L. , Downing J. Micah , Plotkin Kenneth J.
Published: October 2013

A new joint program between Wyle Laboratories, Penn State, and others has been initiated to develop a better noise model for military fighter aircraft. As is well known, the high sound amplitudes produced by modern jets imply the importance of nonlinear effects in the sound propagation. In the literature one can find several experiments clearly showing spectral broadening and the development and coalescence of shocks as the noise propagates with distance. Current U.S. DoD noise models, nevertheless, neglect nonlinear distortion. A number of different nonlinear propagation predictions schemes are available, and currently there is no broad consensus as to which models work best for jet noise. This talk will discuss the applicability of several of these methods to the current need. Only when nonlinear propagation methods have been coded and tested against laboratory and full scale measurements will a predictive tool be available for assessing the environmental noise impacts of modern aircraft. [Work supported by SERDP.]
Experimental and numerical study of air-coupled surface waves generated above strips of finite impedance
Authors: Zhu Wenhao , Daigle Gilles A. , Stinson Michael R.
Published: October 2013

A surface composed of a lattice of small cavities can support the propagation of air-coupled surface waves. Energy is localized near the surface and, since the sound pressure near the surface can be greater than if the surface was rigid, passive amplification is obtained. By restricting the lattice of cavities to a strip of finite width embedded in an otherwise rigid surface, the amplification depends on the direction of the incident sound. Thus directional receivers can be designed. These directional receivers can provide more amplification than would be obtained with a semi-infinite lattice of cavities. In this paper, we will discuss various ways in which strips of finite impedance can be configured to enhance the amplification (and directivity) properties of surface waves. Experiments were carried out on a model surface and the measurements are compared with numerical results obtained using a boundary element method.
Method of designing layered sound absorbing materials
Authors: Atalla Youssef , Panneton Raymond
Published: October 2013

A widely used model for describing sound propagation in porous materials is the Johnson–Champoux–Allard model. This rigid frame model is based on five geometrical properties of the porous medium: resistivity, porosity, tortuosity, and viscous and thermal characteristic lengths. Using this model and with the knowledge of such properties for different absorbing materials, the design of a multiple layered system can be optimized efficiently and rapidly. The overall impedance of the layered systems can be calculated by the repeated application of single layer impedance equation. The knowledge of the properties of the materials involved in the layered system and their physical meaning, allows to perform by computer a systematic evaluation of potential layer combinations rather than do it experimentally which is time consuming and always not efficient. The final design of layered materials can then be confirmed by suitable measurements. A method of designing the overall acoustic absorption of multiple layered porous materials is presented. Some aspects based on the material properties, for designing a flat layered absorbing system are considered. Good agreement between measured and computed sound absorption coefficients has been obtained for the studied configurations. [Work supported by N.S.E.R.C. Canada, F.C.A.R. Quebec, and Bombardier Aerospace.]