bluuebunny/crossref_metadata_2025 huggingface dataset:
Is intelligibility of adjacent passbands hypoadditive or hyperadditive?
Authors: Warren Richard M. , Bashford James A. , Lenz Peter W.
Published: October 2013

Based on their own findings and reports from other laboratories, H. Müsch and S. Buus [H. Müsch and S. Buus, J. Acoust. Soc. Am. 109, 2896–2909 (2001)] suggested that when heard together, the intelligibilities of adjacent passbands were hypoadditive, and those of disjoint passbands were hyperadditive. A subsequent study employed extremely high order far infrared filtering that had been shown to effectively eliminate contributions from transition band slopes [R. M. Warren, J. A. Bashford, Jr., and P. W. Lenz, J. Acoust. Soc. Am. 118, 3261–3266 (2005)]. That study measured the intelligibility for each of the 15 possible pairings of six one-octave effectively rectangular passbands (3 dB/Hz filter skirts) that spanned the speech spectrum with center frequencies ranging from 0.25 to 8 kHz. Each pairing, whether contiguous or disjoint, exhibited hyperadditivity. The present study determined whether decreasing the filter skirts to 0.5 dB/Hz (considered quite steep by conventional standards) would produce the hypoadditivity reported in literature for adjacent bands. Results obtained support the hypothesis that redundancy introduced by overlapping transition band slopes could be responsible for the redundancy correction factor employed by some models for estimating intelligibility of paired adjacent passbands. [Work supported by NIH.]
Optical tracking of acoustic radiation force impulse-induced dynamics in a tissue-mimicking phantom.
Authors: Bouchard Richard , Streeter Jason , Palmeri Mark , Trahey Gregg , Dayton Paul
Published: October 2013

Optical tracking was utilized to investigate the acoustic radiation force impulse (ARFI)-induced response in a translucent, tissue-mimicking phantom. Suspended 10-μm microspheres were tracked axially and laterally at multiple locations throughout a microscope’s field of view with 0.5-μm displacement resolution, in both dimensions, and at frame rates (with an attached video camera) of up to 36 kHz. Induced dynamics was successfully captured before, during, and after the ARFI excitation at depths of up to 4.8 mm from the phantom’s proximal boundary. Results are presented for tracked axial and lateral displacements resulting from on-axis and off-axis (i.e., shear wave) acquisitions; these results are compared to matched finite element method modeling and independent, ultrasonically based empirical results. A shear wave reflection, generated by the proximal boundary, consistently produced an artifact in tracked displacement data later in time (i.e., after the initial ARFI-induced displacement peak). This new tracking method provides high-frame-rate, two-dimensional tracking data and thus could prove useful in the investigation of complex ARFI-induced dynamics in controlled experimental settings. [This work was supported in part by a National Science Foundation Graduate Research Fellowship.]
Modeling temporal weighting of interaural time and level differences in high-rate click trains.
Authors: Stecker G. Christopher , Brown Andrew D.
Published: October 2013

Accurate localization of sound sources requires that information be integrated over time and across multiple spatial cues in a manner that reflects the reliability of those cues over time. Several past studies have investigated the relative weighting of multiple cues (e.g., interaural time-intensity “trading”) as well as the temporal weighting applied to brief stimuli such as noise bursts and impulse trains. The results have demonstrated reduced sensitivity to ongoing envelope interaural time differences in high-frequency, high-rate stimuli and a consequent shift in weighting to favor onset and interaural-level cues. The dominance of onset over ongoing cues is consistent with the precedence effect [Wallach et al., Am. J. Psych. 62:315–336 (1949)] and binaural adaptation [Hafter and Dye, J. Acoust. Soc. Am. 73:644–651 (1983)] and may reflect a combination of (1) peripheral auditory factors, (2) effective modulation, (3) postonset inhibition of binaural information, and (4) temporal integration of ongoing cues. In this study, simple mathematical models are used to study the effects of these factors on temporal weighting of interaural time and level differences in narrowband click trains varying in spectral composition, click timing, and cue availability.
Semi-active shock control technique for two-stage vibration isolation system based on vibration absorption.
Authors: Li Wanyou , Liu Zhigang , Liu Xueguang , Chen Xixia
Published: October 2013

Active control of shock is more difficult due to its instantaneous nature. In this presentation, the use of vibration absorption is proposed to decrease the harm from shock. Simulation and experimental studies are carried out on a two-stage vibration isolation system. The dynamic model of the two-stage vibration isolation system with the semi-active vibration absorber installed is developed. The effect of various parameters of semi-active absorber is analyzed through numerical simulation. The correctness is also validated by the experimental studies. The results show that the optimal installed position is on the upper stage mass, and a set of the optimal absorber parameters exists to make the anti-shock effectiveness achieve best. Such best effectiveness is not affected by the shock amplitude, however, by the continuance time and the excitation waveform. A semi-active vibration reduction and shock resisting control system including electromagnetism semi-active vibration absorber, DSP controller, and constant current source; etc is also designed. The experimental studies on the control effectiveness and reaction time of such system are subsequently performed. It is demonstrated that such a system can work in two working conditions, namely, vibration reduction and shock resisting, these two statutes can transiently switch, and control the secondary shock response effectively.
Passive acoustic determination of herring size.
Authors: Hahn Thomas R. , Wylie Jennifer , Chen Xiaojun
Published: October 2013

Over the last decade, acoustic signatures of a variety of fishes have been recorded and analyzed. More recently, these vocalizations have been used to passively detect aggregations of fish, demonstrating the potential to supplement and enhance traditional active acoustic surveys. Based on previously published work on acoustic emissions of herring, this paper discusses the possibility of not merely passively detecting absence or presence of aggregations of herring but, additionally, assessing abundance and size. Theoretical considerations as well as data collected in Prince William Sound, Alaska, on Pacific herring (Clupea Pallasii) are presented.
A study of two techniques for three-dimensional ultrasonic tomography using inverse scattering.
Authors: Lavarello Roberto J. , Oelze Michael L.
Published: October 2013

A majority of inverse scattering works consider 2D imaging problems. Therefore, the study of 3D inverse scattering methods is necessary for future applications of ultrasonic tomography. Two approaches were examined through simulations for image reconstruction of spherical targets. In the first approach, transducers focused on elevation were used to produce a series of 2D image slices of the object using the distorted Born iterative method (DBIM). The resulting 3D image reconstruction was rendered by stacking serial 2D slices. Typical mean average error (MAE) values in sound speed contrast reconstructions were above 25%. Reconstruction artifacts due to large multiple scattering were identified in addition to the limited spatial resolution in the vertical direction predicted by linear imaging theory. The magnitude of the artifacts decreased with decreasing focal number and also depended on properties of the imaging target (i.e., sound speed contrast and radius). In the second approach, pointlike transducers were used to produce a fully 3D DBIM image reconstruction by inverting the 3D wave equation. Reconstructions using 3D DBIM resulted in MAE values around 13%, and no noticeable artifacts when transducers were properly distributed. The dependence of reconstruction quality on transducer arrangement was studied by analyzing three different array configurations.
Effects of differences in fundamental frequency on cross-formant grouping in speech perception.
Authors: Summers Robert J. , Roberts Brian , Bailey Peter J.
Published: October 2013

In isolated syllables cross-formant perceptual grouping can be promoted by a common fundamental frequency (F0), but this effect is relatively weak [Darwin, Q., J. Exp. Psychol. 33A, 185–207 (1981)]. Few studies have explored the role of F0 in cross-formant grouping using sentences. Three-formant (F1+F2+F3) analog of almost continuously voiced natural utterances were synthesized using a monotonous glottal source (F0=150 Hz). Perceptual organization was probed by presenting stimuli dichotically (F1+F2C+F3; F2), where F2C is a competitor for F2 that listeners must resist to optimize recognition. Competitors were created using time-reversed amplitude and frequency contours of F2, and F0 was manipulated (ΔF0 = ±8, ±2, or 0 semitones relative to the other formants). Adding F2C reduced intelligibility for most utterances, and this reduction was greatest overall when ΔF0=0. However, as for isolated syllables, the effect of ΔF0 was quite small. Competitor efficacy was also somewhat dependent on absolute F0. Manipulation of relative F2C level indicated that competitor efficacy was not due primarily to energetic masking. The modest effect of ΔF0, both for sentences and isolated syllables, suggests that cross-formant grouping depends more on other factors, for example common patterns of modulation. [Supported by EPSRC]
Modeling focused ultrasonic beams through liquid-solid interfaces: Applications to diffuse scattering.
Authors: Turner Joseph A. , Ghoshal Goutam
Published: October 2013

When a focused ultrasonic beam interacts with a liquid-solid interface, the beam profile changes due to the acoustic impedance mismatch between the two materials at the interface. A normal incidence focused beam, for planar or curved liquid-solid interfaces, can be modeled with good accuracy using several well established models such as single Gaussian, a multi-Gaussian, Gauss–Hermite, or Bessel beams, which are often used with a paraxial approximation as well. For oblique angles of incidence, these theories break down and the displacements within the solid are not modeled accurately. If such models are applied to diffuse backscatter experiments, accurate extraction of microstructural parameters becomes difficult. In this presentation, ray models of ultrasonic beams are examined with respect to focusing through a liquid-solid interface at oblique incidence as a function of space and time. The integration of such a beam model within the framework of a diffuse ultrasonic scattering theory is discussed, and the theory is used to interpret diffuse ultrasonic scattering experimental data for which focused beams are used at oblique incidence on polycrystalline metals. These results are anticipated to impact ultrasonic nondestructive evaluation of heterogeneous media.
The effects of quinine on frequency selectivity, temporal resolution, and speech recognition in quiet and noise.
Authors: Williams Erica J. , Bacon Sid P.
Published: October 2013

Quinine causes a temporary disruption of outer hair cell (OHC) function, and thus can be used to examine the role of OHCs on auditory perception. In the present study, frequency selectivity, temporal resolution, and speech recognition were measured before, during, and after a quinine-induced hearing loss. Normal-hearing listeners ingested 5.76–11.43 mg/kg body weight of quinine, resulting in 5–15 dB of hearing loss. Frequency selectivity was estimated by comparing the level of a noise masker needed to mask a fixed-level, 2-kHz signal when the masker contained a spectral gap at 2 kHz and when it contained no gap. Similarly, temporal resolution was estimated by comparing the masker level needed to mask the 2-kHz signal when the noise masker contained a temporal gap and when it did not. Speech recognition thresholds were measured in quiet and in the presence of a masker (speech-shaped noise or time-reversed speech) fixed at 70-dB SPL. Signal level was varied adaptively to estimate 50% correct recognition. Quinine resulted in reduced frequency selectivity and reduced temporal resolution. Quinine also elevated speech recognition thresholds in quiet (by 7 dB on average), but the thresholds in the presence of the maskers were unaffected. [Work supported by NIDCD and AAA.]
Discrimination of American vowels in disyllables mixed in speech babble by experienced Japanese and Russian learners of English.
Authors: Ito Kikuyo , Gilichinskaya Yana, D. , Strange Winifred
Published: October 2013

Previous studies in this laboratory examining speeded discrimination of American English (AE) vowels in quiet by Japanese (JP) and Russian (RU) late L2 learners indicated differences in relative difficulty of non-native contrasts that were predictable from L1 phonological differences. Response latencies were a sensitive measure of continuing L2 perceptual difficulties. In the present study, the same task (a speeded categorial ABX task with disyllabic stimuli) was administered to Japanese and Russian listeners, with stimuli mixed in speech babble at three levels (SNR 0, 6, 12). Eight experimental contrasts (four with spectral plus duration differences and four with spectral differences only) and four control contrasts were tested in lists with both vowel contrast and noise level varying randomly. Results indicated that both L2 groups performed more poorly than native AE control subjects on many of the experimental contrasts, including those differentiated by duration as well as spectral differences. Again differences in relative perceptual difficulty across L2 groups emerged. Perceptual assimilation patterns and performance on a test of English fluency and pronunciation (versant) were correlated with discrimination performance across individuals. [Work supported by NSF.]
Provider registration and reporting requirements.
Authors: Brooks Bennett
Published: October 2013

The Technical Committee on Architectural Acoustics (TCAA) is a Registered Provider in the American Institute of Architects (AIA) Continuing Education System (CES). The TCAA has developed a standardized introductory short course for architects. The TCAA short course is called “Architectural Acoustics” and attendance at this 1-hour-long course can earn an architect one continuing education unit (CEU). This paper will cover the administrative requirements of the AIA/CES, to prepare potential presenters. These requirements include the proper handling of paperwork, so that AIA members may receive credit for the course. Also, the manner in which the course is given is dictated by AIA requirements. TCAA membership and attendance at this workshop are required to qualify as an authorized presenter for this AIA/CES short course.
Measuring the Young’s modulus of reeds from American reed organs.
Authors: Wilson Michael B. , Ramm Alexander M. , Cottingham James P.
Published: October 2013

A method of wave coefficients has been used to measure the Young’s modulus of brass reeds from American reed organs. Although for some purposes these reeds can be approximated as uniform cantilever beams, their cross sections are sufficiently nonuniform that simple methods such as measuring beam displacement for a known applied force or using resonant frequencies of transverse and torsional modes of vibration are not sufficient to obtain accurate results. In the wave coefficient method [Y. Liao and V. Wells, J. Sound Vibr. 295, 165–193 (2006)] a wave number is found that forces data at all measurement points to conform to the general forced-vibration solution for a beam, implying that they have the same wave coefficients. This method also assumes a uniform cross section but does not require measurements along the entire length of the beam and was applied only to the most uniform sections of the reeds. Three reeds of the same frequency were selected, with cross sections of varying uniformity. The resulting measurements of the Young’s modulus seemed consistent with expected values for brass. For one reed with nearly uniform cross section the wave coefficient method was in good agreement with the simpler methods.
Perception of Mandarin Chinese tone 2/tone 3 and the role of creaky voice.
Authors: Cao Rui , Wayland Ratree
Published: October 2013

Previous research has established that among the four tones of Mandarin Chinese, tone 2 and tone 3 are very similar in their pitch contour shapes and are, thus, difficult to distinguish by native and nonnative listeners. On the other hand, creaky voice has been reported to be associated with tone 3 production among native speakers. However, the role of creaky voice in the perception of tone 3 has yet to be studied systematically. This study aims to investigate (1) the extent to which creaky voice is present in tone 3 production by native speakers; (2) the perceptual boundary between tone 2 and tone 3 among native and non-native speakers; and (3) the effect of creaky phonation on this perceptual boundary. Thirty native Chinese speakers and 30 native speakers of American English who are learning Chinese will participate in this study. Tone stimuli with and without creaky voice will be presented auditorily for tonal identification. The data obtained will be analyzed to examine the effect of creaky voice in the identification of tone 3 among these two groups of speakers. In addition, the native production of tone 3 will be examined for the presence of creaky voice.
Autocorrelation models of pitch perception.
Authors: Yost William A.
Published: October 2013

In 1951, Licklider first suggested autocorrelation as a method to model pitch perception in his Duplex and Triplex Theories. It was not until 1991 that a full-fledged autocorrelation model was developed by Meddis and Hewitt. Over the past decades several investigators have refined autocorrelation or autocorrelation-like models to account for pitch perception and processing. While there have been a few arguments against autocorrelation for explaining pitch phenomena, autocorrelationlike models have been very successful in accounting for a wide range of data including those associated with the pitch of iterated ripple noise. This presentation will review the development of autocorrelation models of pitch perception, especially in accounting for the pitch and pitch strength of iterated ripple noise. The presentation will also cover how refining well-established models or theories may offer a good opportunity for developing skills to build additional models and theories. [Work supported by a grant from NIDCD.]
Dual-task costs in speech recognition by older and younger listeners.
Authors: Helfer Karen S. , Chevalier Jamie , Freyman Richard L.
Published: October 2013

This study examined performance of younger and older adults when they carried out two auditory tasks simultaneously versus when performing each task in isolation. One task was to repeat a target sentence spoken by a male talker, presented simultaneously with two masking sentences spoken by two other male talkers. The second task was to judge whether neither, one, or both voices in the two-talker masker complex was presented time-reversed. Data were collected in both spatially-separated and colocated conditions. Results showed substantial individual variability within both subject groups as well as a strong effect of trial type order. Performance by most listeners declined to a greater extent for the natural/time-reversed task than for the speech recognition task during divided attention, even though subjects were instructed to give the two tasks equal weight. Importantly, requiring listeners to divide attention decreased or eliminated the spatial separation advantage for listening to speech in a competing speech situation. The poster will discuss differences noted between the two groups in overall performance as well as in the costs of dividing attention. [Work supported by NIH DC01625.]
Two-dimensional normal modes: Experiment and finite element analysis.
Authors: Hansen Uwe J.
Published: October 2013

Bending wave propagation on a two-dimensional plate is reduced to standing waves with the imposition of boundary conditions. These standing wave patterns can be observed with sand, which accumulates near the nodal lines. These sand patterns are usually called Chladni patterns after Chladni, who first observed and described them. Using a simple lapel microphone, these mode patterns can also be illustrated by noting the phase shift when observing the near-field sound pattern very close to the vibrating plate. Both Chladni patterns and phase mapping of patterns will be illustrated. A relatively inexpensive software package enables finite element calculations of vibrating plates. Normal mode vibration can easily be illustrated in animation on a computer screen. Both the calculation process and the animation will be illustrated.
Simultaneous acoustic tag and seafloor acoustic recorder detection of right whale calls in the Bay of Fundy.
Authors: Parks Susan E. , Clark Christopher W. , Johnson Mark , Tyack Peter L.
Published: October 2013

Passive acoustic monitoring is playing a growing role in marine mammal detection. Determining the range of detection for calls of a particular species in a particular location is important to assess the regional coverage provided by individual recording units. This study describes the comparison of right whale calls recorded by digital acoustic recording tags (Dtags) attached with suction cups to North Atlantic right whales and the detection of the same calls using a dispersed seafloor array of autonomous recorders. The seafloor array consisted of 5 units, spaced 6–10 km apart, continuously recording from July 29– August 17, 2005. Dtags were attached to a total of 14 individual right whales during this time period and 7 of these individuals produced a total of 88 tonal calls during tag attachment. The tag and related tracking of the whale provided information on call type, and the timing, depth, and approximate location of the whale producing the call. Tagged whale calls were audible on the seafloor array, and whale-recorder distances provided estimates of the acoustic detection range for right whales in the Bay of Fundy, Canada.
Inversions from source of opportunity data collected on horizontal and vertical line arrays.
Authors: Stotts Steven A. , Koch Robert A. , Joshi Sumedh M. , Nguyen Vian T. , Knobles David P.
Published: October 2013

Environmental and source track parameter values were extracted by coherent spatial and temporal field processing of data from a ship of opportunity source that were recorded on collocated horizontal and vertical arrays. The data were collected during the Shallow Water 2006 (SW06) experiment in a continental shelf, sandy sediment environment with a water depth of approximately 70 m. Inversion solutions for environmental and source track parameter values were obtained from both conventionally and adaptively beamformed subaperture data over a 5-km range scale. The inversion solution for the data from the source to the closest point of approach (CPA) is presented and compared to the prior information on the seabed parameter values provided by geophysical measurements and inversions using other measured acoustic data. The coherent received field structure for the source departing from CPA is compared to the model predictions obtained from the inversion solution for the seabed parameter values. Inversion solutions from the vertical line array data are compared to those obtained from the horizontal line array data. [This work is supported in part by ONR.]
Compact microphone array processing for in-vehicle voice detection applications.
Authors: Hoppe Elizabeth A. , Roan Michael J.
Published: October 2013

The main goal of voice activity detection algorithms is to determine the presence of human voice signals in a given environment. Voice activity detection is very challenging in vehicle interiors. The main challenge in detecting the presence of voice signals in vehicles is the presence of a large number of interferers and a high background noise level. Further, many types of interferers such as tire or engine noise have signals that are highly nonstationary. In this work, compact microphone arrays mounted in various locations within a vehicle are used to extract signals from locations of interest. Experimental comparisons of the performance of several voice activity detection algorithms are made for various array configurations (including single microphone) and source extraction processing algorithms. Processing algorithms considered include blind source separation algorithms such as fastICA, transfer function based inversion methods, and both fixed and adaptive beamforming techniques. The performance of compact arrays is also compared to the performance of larger distributed microphone arrays. It is shown that the use of compact microphone arrays can significantly improve voice activity detection algorithms. The gain is quantified using receiver operating characteristic type curves plotting probability of detection vs probability of false alarm.
Response of Free-Living Nitrogen-Fixing Microorganisms to Land Use Change in the Amazon Rainforest
Authors: Mirza Babur S. , Potisap Chotima , Nüsslein Klaus , Bohannan Brendan J. M. , Rodrigues Jorge L. M.
Published: October 2013

The Amazon rainforest, the largest equatorial forest in the world, is being cleared for pasture and agricultural use at alarming rates. Tropical deforestation is known to cause alterations in microbial communities at taxonomic and phylogenetic levels, but it is unclear whether microbial functional groups are altered. We asked whether free-living nitrogen-fixing microorganisms (diazotrophs) respond to deforestation in the Amazon rainforest, using analysis of the marker gene
nifH
. Clone libraries were generated from soil samples collected from a primary forest, a 5-year-old pasture originally converted from primary forest, and a secondary forest established after pasture abandonment. Although diazotroph richness did not significantly change among the three plots, diazotroph community composition was altered with forest-to-pasture conversion, and phylogenetic similarity was higher among pasture communities than among those in forests. There was also 10-fold increase in
nifH
gene abundance following conversion from primary forest to pasture. Three environmental factors were associated with the observed changes: soil acidity, total N concentration, and C/N ratio. Our results suggest a partial restoration to initial levels of abundance and community structure of diazotrophs following pasture abandonment, with primary and secondary forests sharing similar communities. We postulate that the response of diazotrophs to land use change is a direct consequence of changes in plant communities, particularly the higher N demand of pasture plant communities for supporting aboveground plant growth.
Metatranscriptomic Analyses of Plankton Communities Inhabiting Surface and Subpycnocline Waters of the Chesapeake Bay during Oxic-Anoxic-Oxic Transitions
Authors: Hewson Ian , Eggleston Erin M. , Doherty Mary , Lee Dong Yoon , Owens Michael , Shapleigh James P. , Cornwell Jeffrey C. , Crump Byron C.
Published: October 2013

We used metatranscriptomics to study the gene transcription patterns of microbial plankton (0.2 to 64 μm) at a mesohaline station in the Chesapeake Bay under transitions from oxic to anoxic waters in spring and from anoxic to oxic waters in autumn. Samples were collected from surface (i.e., above pycnocline) waters (3 m) and from waters beneath the pycnocline (16 to 22 m) in both 2010 and 2011. Metatranscriptome profiles based on function and potential phylogeny were different between 2010 and 2011 and strongly variable in 2011. This difference in variability corresponded with a highly variable ratio of eukaryotic to bacterial sequences (0.3 to 5.5), reflecting transient algal blooms in 2011 that were absent in 2010. The similarity between metatranscriptomes changed at a lower rate during the transition from oxic to anoxic waters than after the return to oxic conditions. Transcripts related to photosynthesis and low-affinity cytochrome oxidases were significantly higher in shallow than in deep waters, while in deep water genes involved in anaerobic metabolism, particularly sulfate reduction, succinyl coenzyme A (succinyl-CoA)-to-propionyl-CoA conversion, and menaquinone synthesis, were enriched relative to in shallow waters. Expected transitions in metabolism between oxic and anoxic deep waters were reflected in elevated levels of anaerobic respiratory reductases and utilization of propenediol and acetoin. The percentage of archaeal transcripts increased in both years in late summer (from 0.1 to 4.4% of all transcripts in 2010 and from 0.1 to 6.2% in 2011). Denitrification-related genes were expressed in a predicted pattern during the oxic-anoxic transition. Overall, our data suggest that Chesapeake Bay microbial assemblages express gene suites differently in shallow and deep waters and that differences in deep waters reflect variable redox states.
Diversity of Rickettsiales in the Microbiome of the Lone Star Tick, Amblyomma americanum
Authors: Ponnusamy Loganathan , Gonzalez Antonio , Van Treuren Will , Weiss Sophie , Parobek Christian M. , Juliano Jonathan J. , Knight Rob , Roe R. Michael , Apperson Charles S. , Meshnick Steven R.
Published: October 2013

Ticks are important vectors for many emerging pathogens. However, they are also infected with many symbionts and commensals, often competing for the same niches. In this paper, we characterize the microbiome of
Amblyomma americanum
(Acari: Ixodidae), the lone star tick, in order to better understand the evolutionary relationships between pathogens and nonpathogens. Multitag pyrosequencing of prokaryotic 16S rRNA genes (16S rRNA) was performed on 20 lone star ticks (including males, females, and nymphs). Pyrosequencing of the rickettsial
sca0
gene (also known as
ompA
or
rompA
) was performed on six ticks. Female ticks had less diverse microbiomes than males and nymphs, with greater population densities of
Rickettsiales
. The most common members of
Rickettsiales
were “
Candidatus
Rickettsia amblyommii” and “
Candidatus
Midichloria mitochondrii.” “
Ca
. Rickettsia amblyommii” was 2.6-fold more common in females than males, and there was no sequence diversity in the
sca0
gene. These results are consistent with a predominantly vertical transmission pattern for “
Ca
. Rickettsia amblyommii.”
Molecular Investigation and Phylogeny of Anaplasma spp. in Mediterranean Ruminants Reveal the Presence of Neutrophil-Tropic Strains Closely Related to A. platys
Authors: Zobba Rosanna , Anfossi Antonio G. , Pinna Parpaglia Maria Luisa , Dore Gian Mario , Chessa Bernardo , Spezzigu Antonio , Rocca Stefano , Visco Stefano , Pittau Marco , Alberti Alberto
Published: October 2013

Few data are available on the prevalence and molecular typing of species belonging to the genus
Anaplasma
in Mediterranean ruminants. In this study, PCR analysis and sequencing of both 16S rRNA and
groEL
genes were combined to investigate the presence, prevalence, and molecular traits of
Anaplasma
spp. in ruminants sampled on the Island of Sardinia, chosen as a subtropical representative area. The results demonstrate a high prevalence of
Anaplasma
spp. in ruminants, with animals infected by at least four of six
Anaplasma
species (
Anaplasma marginale
,
A. bovis
,
A. ovis
, and
A. phagocytophilum
). Moreover, ruminants host a number of neutrophil-tropic strains genetically closely related to the canine pathogen
A. platys
. The high
Anaplasma
spp. prevalence and the identification of as-yet-unclassified neutrophil-tropic strains raise concerns about the specificity of serological tests routinely used in ruminants and provide additional background for reconstructing the evolutionary history of species genetically related to
A. phagocytophilum
.
Acupuncture Treatment for Hypertension: A Case Study
Authors: Zhang Lili , Shen Pengfei , Wang Shu
Published: October 2013

This report describes the regular use of acupuncture treatments for a patient with hypertension who could not tolerate the side effects of the antihypertensive agents. The patient received 60 acupuncture treatments in the course of 12 weeks, during which time his overall wellbeing improved, his blood pressure reduced and the side effects of antihypertensive drugs were removed. Although acupuncture plus the drug appeared to have a substantial synergistic effect that was weakened when the drug was discontinued, acupuncture may still play a role in the management of hypertension, especially for patients who cannot tolerate the side effects of antihypertensive agents.
Elevated free thyroxine and non-suppressed thyrotropin
Authors: Mok Shao Feng , Loh Tze Ping , Venkatesh Byrappa , Deepak Doddabele Srinivasa
Published: October 2013

A young man was diagnosed with hyperthyroidism 10 years prior to current presentation after a random health screening revealed an elevated free thyroxine (fT4) of 36.9 pmol/L. During that time, he saw multiple physicians and was treated with carbimazole intermittently. His repeat thyroid function tests showed persistently elevated fT4 ranging 25–35.7 pmol/L and non-suppressed thyroid-stimulating hormone (TSH) concentrations of 6.78–22.1 mIU/L. He had a smooth, firm and non-tender goitre. At our institution, laboratory interference was first excluded by serial dilution study (TSH) and retesting of TSH and fT4 on alternate assay, which gave reproducible results. His normal α-subunit and sex hormone binding globulin, partially suppressed TSH by high dose triiodothyronine (T3), and positive TSH response to thyrotropin-releasing hormone stimulation were consistent with resistance to thyroid hormone syndrome. The diagnosis was confirmed by direct sequencing of thyroid hormone receptor-β gene, revealing a heterozygous R320 L mutation that causes reduced T3 affinity and reduced corepressor dissociation.
The effects of subarachnoid administration of hyperbaric solutions of bupivacaine or ropivacaine in xylazine‐sedated calves undergoing surgery
Authors: Yayla S. , Kilic E. , Aksoy O. , Ozaydin I. , Ogun M. , Steagall P.V.M.
Published: October 2013

The aim of this study was to compare the effects of subarachnoid administration of hyperbaric solutions of bupivacaine or ropivacaine in xylazine‐sedated calves undergoing surgery. Subarachnoid anaesthesia was performed with either 20 mg of hyperbaric bupivacaine (bupivacaine group (BG), n=10) or 30 mg of hyperbaric ropivacaine (ropivacaine group (RG), n=10) into the lumbar dural space of 20 calves in a randomised, prospective clinical trial. Systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure, heart rate (HR), respiratory rate, rectal temperature were recorded after sedation (time 0), and up to 120 minutes after injection. Onset, duration and magnitude of sensory block (scale 1–4) were determined using the pin‐prick test throughout surgery. Data were analysed using analysis of variance and non‐parametric tests (P<0.05). Bodyweight, age, duration of surgery, SBP, DBP, MBP, HR were not significantly different between groups. Onset of anaesthesia (mean±sd; BG, 5±1 minutes; RG, 7±1 minutes) and duration of anaesthesia (mean±sd; BG, 153±32 minutes; RG, 86±12 minutes) were significantly different between groups. Analgesic scores were significantly higher than baseline from 5 to 120 min, and from 7 to 85 min in BG and RG, respectively. Subarachnoid administration of hyperbaric solutions of bupivacaine produced faster onset and longer duration of anaesthesia than ropivacaine.
Keel fracture assessment of laying hens by palpation: inter‐observer reliability and accuracy
Authors: Petrik M. T. , Guerin M. T. , Widowski T. M.
Published: October 2013

The objective of this study was to assess the interobserver reliability (agreement) and accuracy of keel palpation for the purpose of detecting old fractures in an end‐of‐lay flock of commercial laying hens. The low level of invasiveness and the relative speed at which this evaluation can be carried out lends itself well to use in a welfare audit, but only if the results are reliable and accurate from various assessors. The palpation technique first described by Wilkins and others (2004) was used to manually palpate for keel fractures. The technique was modified in that only keel fractures were considered. Eight assessors with varying laying hen experience palpated 100 live ISA Brown hens that had been in lay for 49 weeks. The hens were then euthanased and examined by dissection to establish whether there had been a keel fracture present (yes/no). The accuracy for individual assessors ranged from 87.1 to 96.8 per cent, with a mean of 91.8 per cent among all eight assessors. The interobserver reliability among all eight assessors was moderate (=0.44). Accuracy and κ values were 84.8 per cent and 0.41 for the first 50 hens, and 99.5 per cent and 0.47 for the last 50 hens, respectively, indicating that there was increased accuracy and agreement as the assessors became more experienced at palpation. This level of agreement, and the high level of accuracy, would make this technique an acceptable measure of keel fracture prevalence in a welfare audit.
Factors affecting the accuracy of pregnancy scanning in ewes
Authors: Fridlund C. , Humblot P. , Båge R. , Söderquist L.
Published: October 2013

The objective was to evaluate the accuracy of pregnancy scanning by transabdominal ultrasonography and affecting factors. Altogether 44,783 ewes were registered (2008–2010), 39,724 diagnosed as pregnant and subsequently lambed. The ewes, 0.5–14 years old, were divided into 4 age and 6 breed groups and analysed. The accuracy (per cent; number of scanned fetuses/number of born lambs) decreased with increasing number of fetuses (P < 0.001). Overall accuracy was 90.3 per cent, highest (93.7 per cent) in ewes carrying one fetus, 91.9 per cent, 82.4 per cent, and 74.9 per cent in ewes with 2, 3 and ≥4 fetuses at scanning, respectively. Finnsheep ewes with highest number of lambs showed lowest accuracy (P < 0.001). Analyses of a more complete sub set of data (n = 23,396), showed that number of fetuses diagnosed, breed, age of ewe, operator and time in gestation, significantly affected the accuracy. Accuracy decreased with age of ewe (P < 0.001) and was 71.8 per cent, 91.6 per cent and 89.3 per cent for scanning at <40, 40–80 and 81–100 days of gestation, respectively (P < 0.001). In general, the numbers of fetuses were overestimated at scanning and increased gradually with number of fetuses diagnosed. In conclusion, the accuracy was affected by several factors, which should be considered when interpreting/implementing the results, especially in breeds with high fecundity.
Pullout behaviour of plate anchor in clay with linearly increasing strength
Authors: Tho Kee Kiat , Chen Zongrui , Leung Chun Fai , Chow Yean Khow
Published: October 2013

Plate anchors are widely adopted to provide uplift resistance for structures. For most offshore seabeds, the undrained shear strength profile can be reasonably approximated as varying linearly with depth. At present, there are two possible approximate approaches to determine uplift capacity of a square plate anchor in such a profile, but the validity of both approaches cannot be ascertained due to unavailability of a rigorous solution. This study addresses these uncertainties by establishing the capacity factors for a square anchor in a linearly increasing strength profile using a three-dimensional large-deformation finite element approach for a wide range of geometric and material combinations. It was found that both approaches give the correct solution only under specific conditions. Earlier studies on the uplift capacity of a plate anchor typically follow a classical path of deriving the solution for a weightless soil and extending this solution to a soil with self-weight. The applicability of such an approach to the uplift of a square anchor is examined in this study. A direct design method for a square plate anchor embedded in a linearly increasing strength profile, which enables the capacity factors for a square anchor to be directly obtained without any simplified assumptions, is then proposed.
Evidence of long and discontinuous juvenile periods in Trillium catesbaei under contrasting levels of herbivory
Authors: Webster Christopher R. , Jenkins Michael A.
Published: October 2013

We investigated the influence of chronic herbivory by white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) on the age structure and morphology of Trillium catesbaei Elliott. At sites with contrasting histories of deer abundance (Cades Cove, high; Whiteoak Sink, low), we measured morphological characteristics and determined minimum plant age for 60 plants (30 per site) in the single-leaf life-history stage. We chose this stage because its presence is considered an indication of successful reproduction by the previous generation, but its value could be inflated if plants regress or remain in this stage for extended periods. Our results suggest that T. catesbaei may spend upwards of a decade in this stage. Cades Cove single leaves were significantly older (p = 0.011) than those at Whiteoak Sink. Rhizome recession (decay of the oldest portion) was more common at Cades Cove, suggesting greater regression to this stage from three-leaf stages. Although minimum plant age was significantly associated with vegetative attributes (p < 0.002) at Whiteoak Sink, these attributes were decoupled at Cades Cove (p ≥ 0.642). Collectively, our results suggest that chronic herbivory may lead to a long and regressive residency period in the single-leaf stage. Consequently, in Trillium populations heavily impacted by deer, the number of single-leaf plants may be a poor indicator of reproductive success and population viability.
Population fluctuations and distribution of staging Eared Grebes (Podiceps nigricollis) in North America
Authors: Roberts Anthony J. , Conover Michael R. , Luft John , Neill John
Published: October 2013

Eared Grebes (Podiceps nigricollis Brehm, 1831) use saline ecosystems throughout much of their life cycle, and greater than 90% of the North American population stage during fall at two hypersaline lakes. At one of these lakes, Great Salt Lake (GSL), Utah, a commercial harvest of brine shrimp (Artemia franciscana Kellogg, 1906) cysts occurs during fall and may impact Eared Grebe populations. We used photo surveys on the other hypersaline lake, Mono Lake, California, and on the GSL, as well as aerial counts on the GSL, to describe population fluctuations of Eared Grebes staging on these lakes. The long-term (1997–2012) Eared Grebe population was 1.4 million on the GSL and 1.0 million on Mono Lake. Populations changed on GSL and Mono Lake in synchrony, indicating population regulation is likely occurring at wintering, not staging, areas and is influenced by El Niño effects. Location of Eared Grebes on the GSL was influenced by brine shrimp densities and did not overlap with concentrations of commercial harvest boats. Spatial segregation of commercial harvesters and Eared Grebes reduces negative impacts of anthropogenic disturbance on Eared Grebes. Knowledge of population changes within and among staging areas will help managers monitor long-term abundances and reduce negative impacts between Eared Grebes and commercial harvesters.
Free energies in a general non-local theory of a material with memory
Authors: Amendola Giovambattista , Fabrizio Mauro , Golden John Murrough
Published: October 2013

A general theory of non-local materials, with linear constitutive equations and memory effects, is developed within a thermodynamic framework. Several free energy and dissipation functionals are constructed and explored. These include an expression for the minimum free energy and a functional that is a free energy for important categories of memory kernels and is explicitly a functional of the minimal state. The functionals discussed have a similar general form to the corresponding expressions for simple materials. A number of new results are derived for them, most of which apply equally to both types of material. In particular, detailed formulae are given for these quantities in the case of sinusoidal histories.
Intrinsic formulation of the displacement-traction problem in linearized elasticity
Authors: Ciarlet Philippe G. , Mardare Cristinel
Published: October 2013

The displacement-traction problem of linearized elasticity is a system of partial differential equations and boundary conditions whose unknown is the displacement field inside a linearly elastic body. We explicitly identify here the corresponding boundary conditions satisfied by the linearized strain tensor field associated with such a displacement field. Using this identification, we are then able to provide an intrinsic formulation of the displacement-traction problem of linearized elasticity, by showing how it can be recast into a boundary value problem whose unknown is the linearized strain tensor field.
BALANCED UNITARY CAYLEY SIGRAPHS OVER FINITE COMMUTATIVE RINGS
Authors: MEEMARK YOTSANAN , SUNTORNPOCH BORWORN
Published: October 2013

Let R be a finite commutative ring with identity 1. The unitary Cayley graph of R, denoted by GR, is the graph whose vertex set is R and the edge set {{a, b} : a, b ∈ R and a - b ∈ R×}, where R× is the group of units of R. We define the unitary Cayley signed graph (or unitary Cayley sigraph in short) to be an ordered pair 𝒮R = (GR, σ), where GR is the unitary Cayley graph over R with signature σ : E(GR) → {1, -1} given by [Formula: see text] In this paper, we give a criterion on R for SR to be balanced (every cycle in 𝒮R is positive) and a criterion for its line graph L(𝒮R) to be balanced. We characterize all finite commutative rings with the property that the marked sigraph 𝒮R,μ is canonically consistent. Moreover, we give a characterization of all finite commutative rings where 𝒮R, η(𝒮R) and L(𝒮R) are hyperenergetic balanced.
PASSIVE COUNTERPULSATION: BIOMECHANICAL RATIONALE AND CLINICAL VALIDATION
Authors: CORAZZA IVAN , MELANDRI GIOVANNI , NANNI SAMUELE , MARCELLI EMANUELA , CERCENELLI LAURA , BIANCHINI DAVID , VAGNARELLI FABIO , ZANNOLI ROMANO
Published: October 2013

Intra-aortic balloon counterpulsation (IABP) is the leading technique for cardiovascular support in most critical conditions. The beneficial effects of the procedure are widely known, but some drawbacks remain unsolved: high cost and controversial effect in presence of cardiac arrhythmia, both related to the control of intra-aortic balloon inflation and deflation. This paper describes the clinical validation of a completely passive solution (PIABP), which substitutes the time-controlled pumping system by a simple pressure-controlled reservoir. The test was performed on 10 patients, switching from IABP to PIABP and changing the reservoir pressure to obtain an optimal effect in terms of mean aortic pressure increase as an estimate of cardiac output. For each patient the reservoir pressure was increased in 10 mmHg steps and the aortic pressure was recorded together with electrocardiogram.

The PIABP showed a positive effect in all the patients, with a significant increase of the mean aortic pressure (+6.5%, p < 0.05) and of the mean pressure of the aortic pulse diastolic phase (+7%, p < 0.05). The change of heart rate between basal and optimal effect condition was not significant. Also an unexpected, significant increase of aortic maximal pressure (8%, p < 0.05) was found.

The proposed passive solution cannot be a substitute of the active one in all the situation, but may be useful in border line conditions, where the IABP is no more necessary but a ventricular support is still desirable.