bluuebunny/crossref_metadata_2025 huggingface dataset:
Should We Optimize Cardiac Resynchronization Therapy During Exercise?
Authors: BOGAARD MARGOT D. , KIRKELS J. HANS , HAUER RICHARD N.W. , LOH PETER , DOEVENDANS PIETER A. , MEINE MATHIAS
Published: June 2010

Should We Optimize CRT During Exercise? Cardiac resynchronization therapy aims at diminishing cardiac dyssynchrony in patients with heart failure. The effect of cardiac resynchronization therapy can be improved by optimization of the atrioventricular (AV) and interventricular (VV) delays. Currently, optimization of these pacing settings is mainly performed during resting conditions. This paper aims to objectively review the current literature about a rate‐adaptive AV and VV delay in cardiac resynchronization therapy. The current evidence for a rate‐adaptive AV and VV delay comprises only small nonrandomized studies on acute effects. The effect of exercise on the optimal AV delay was heterogeneous between studies. The optimal VV delay was influenced by exercise conditions in some, but not all patients. Possible explanations lie in the heterogeneous electrical and mechanical responses to exercise in patients with a complex disease such as heart failure with asynchronous contraction. Current evidence is insufficient to show the superiority of a rate‐adaptive AV or VV delay in all CRT patients. Individualized exercise programming may be warranted in selected patients. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1307‐1316, November 2010)
Trepopnea Associated with Paroxysmal Severe Tricuspid Regurgitation Triggered at Left Lateral Decubitus Position
Authors: Wolf David , Benz Andreas , Hardt Stefan E. , Katus Hugo A. , Mereles Derliz
Published: June 2010

A 78‐year‐old male patient was referred cardiovascular risk evaluation before elective resection of a bronchial carcinoma. A myocardial infarction with a subsequent coronary artery bypass revascularization and a mitral prosthetic valve surgery were known. Left lateral decubitus (LLD) was permanently avoided because of significant trepopnea since several years. No signs of heart failure were found in the physical examination. A mitral valve prosthesis presented normal characteristics at examination. Left ventricular dimensions and function were normal. A severe tricuspid regurgitation could be documented during examination in the LLD, with changing characteristics in dorsal decubitus, when it could be graded as moderate. Trepopnea associated with severe paroxysmal tricuspid regurgitation was never described before in the literature. Sympathetic/parasympathetic modulation of papillary muscles of the tricuspid valve can be proposed as a probable cause of this dynamic valvular dysfunction. (Echocardiography 2010;27:E77‐E79)
Characterization of Confined Intact and Damaged Borosilicate Glass
Authors: Chocron Sidney , Anderson Charles E. , Nicholls Arthur E. , Dannemann Kathryn A.
Published: June 2010

This article describes two different techniques utilized to characterize intact and damaged borosilicate glass at pressures up to ∼2 GPa: triaxial compression and confined sleeve. The results of the characterization experiments—for intact and damaged glass as a function of confinement pressure—are described; the results are interpreted in terms of two pressure‐dependent constitutive models: Drucker–Prager and Mohr–Coulomb (MC). The MC model is successful at predicting the damage pattern. An observation is that the slopes of the two models appear to be independent of the degree of damage (intact, predamaged, and severely damaged specimens). Lastly, these data are compared with flyer‐plate impact data of intact and damaged glass.
Reconstruction of the Cubic and Tetragonal Parent Grains from Electron Backscatter Diffraction Maps of Monoclinic Zirconia
Authors: Cayron Cyril , Douillard Thierry , Sibil Arnaud , Fantozzi Gilbert , Sao‐Jao Sergio
Published: June 2010

Monoclinic zirconia results from cubic→tetragonal→monoclinic phase transformations occurring at high temperature. Electron backscatter diffraction maps of monoclinic zirconia in fused‐cast refractories have been treated with new crystallographic computer programs. The correct orientation relationships between the three phases have been identified among those proposed in the literature, the tetragonal and cubic parent grains have been automatically reconstructed, and the variants have been indexed. This example illustrates the possibilities of automatic crystallographic reconstruction software to study complex phase transition materials.
Effects of CuO on the Electrical Properties of CaTiO3‐Modified [(Na0.52K0.48)0.955Li0.045](Nb0.955Sb0.045)O3 Lead‐Free Piezoceramics
Authors: Huang Xiaolei , Xiao Dingquan , Li Xuhai , Wu Wenjuan , Liang Wenfeng , Xie Ruishi , Zhu Jianguo
Published: June 2010

CuO‐doped and undoped 0.99[(Na0.52K0.48)0.955Li0.045](Nb0.955Sb0.045)O3–0.01CaTiO3 (KNNLSCT) lead‐free piezoelectric ceramics have been synthesized by the conventional ceramic processing, where the effects of CuO on the phase structure and electrical properties were studied. All ceramics possess a perovskite structure with tetragonal symmetry. Because of the dipolar complex migration, the P–E loops of undoped ceramics become slanted and constricted at a high temperature, while this phenomenon disappears after the addition of CuO. The d33 value decreases with the increasing poling temperature for the undoped ceramics, while the d33 value increases with the increasing poling temperature after the addition of CuO. These phenomena have been explained by a model based on the formation of the defect polarization induced by spontaneous polarization, indicating that the spontaneous defect polarization has an important influence on the ferroelectric behavior of the KNNLSCT ceramics.
Examining the Attitude–Behavior Relationship in Prosocial Donation Domains
Authors: Anker Ashley E. , Feeley Thomas Hugh , Kim Hyunjung
Published: June 2010

Positive attitudes have been identified across prosocial donation domains, but have not translated into a stable donor base. One explanation for this attitude‐behavior inconsistency is a failure to consider the affective and cognitive components of attitude. Studies were conducted to examine vested interest as a moderator of the attitude–behavior relationship in donation, while accounting for the multidimensional construction of attitude. Study 1 revealed a 3‐factor structure (stake, salience, self‐efficacy) for vested interest. Study 2 found no support for vested interest as a moderator of the attitude–behavior relationship, but revealed that self‐efficacy mediated the relationship between attitudes and behaviors for organ/tissue and blood donation. Results are discussed in terms of the usefulness of this research in crafting donation campaigns.
Reactivity to Stress: When Does a History of Medical Adversity Foster Resilience Versus Vulnerability?
Authors: Bugental Daphne B. , Beaulieu David , Fowler Erin , O'Brien Eileen , Cayan Laura
Published: June 2010

Young adults with (or without) a history of medical or physical disorders (MPDs) were exposed to repeated laboratory stress. The effects of MPD status on habituation (as measured by changing levels of cortisol) were found to be moderated by the extent to which respondents reported “attachment feelings” in their relationships (as measured by the Social Provisions Scale). Students in the MPD group who reported attachment feelings showed (a) cortisol increases during their first exposure to a laboratory stressor; and (b) cortisol decreases during a second exposure to the same stressor 1 week later. No equivalent benefit was found for students who lacked this medical history. Findings suggest the extent to which medical adversity—under the right interpersonal circumstances—promotes resilience.
A Comparison of What U.S. Judges and Students Know and Believe About Eyewitness Testimony
Authors: Wise Richard A. , Safer Martin A.
Published: June 2010

We compared what 160 U.S. judges, 57 law students, and 121 undergraduates know and believe about factors affecting the accuracy of eyewitness testimony. Judges were no more knowledgeable than were undergraduates, and both groups were less knowledgeable than were law students. For all 3 groups, increased knowledge of eyewitness factors was associated with beliefs that might reduce wrongful convictions. Participants in all 3 groups underestimated what potential jurors know about eyewitness testimony. The results suggest that increasing judges' knowledge of eyewitness testimony might help them to reduce wrongful convictions and to more accurately assess when eyewitness experts are needed. The results also suggest that law schools need to do a better job of educating law students about eyewitness testimony.
Narcissism and Aggressive Driving: Is an Inflated View of the Self a Road Hazard?
Authors: Lustman Michèle , Wiesenthal David L. , Flett Gordon L.
Published: June 2010

A total of 210 drivers varying in levels of trait narcissism were presented with 10 scenarios of objectionable driving situations and were asked to make assessments of intentionality, level of inconsideration, and anger and to indicate the behavioral responses they would likely make in such situations. It was hypothesized that responses would reflect attributions made in assessing the behaviors of other motorists. Our results confirmed the associations among attributions, anger, and behavioral reactions. Positive correlations were found between attributions and levels of anger and driver aggression. Individuals high in narcissism were also found to respond more aggressively toward the frustrating driving behavior of others, but this relationship varied by gender and anger experience.
Factors Affecting the Item Parameter Estimation and Classification Accuracy of the DINA Model
Authors: De La Torre Jimmy , Hong Yuan , Deng Weiling
Published: June 2010

To better understand the statistical properties of the deterministic inputs, noisy “and” gate cognitive diagnosis (DINA) model, the impact of several factors on the quality of the item parameter estimates and classification accuracy was investigated. Results of the simulation study indicate that the fully Bayes approach is most accurate when the prior distribution matches the latent class structure. However, when the latent classes are of indefinite structure, the empirical Bayes method in conjunction with an unstructured prior distribution provides much better estimates and classification accuracy. Moreover, using empirical Bayes with an unstructured prior does not lead to extremely poor results as other prior‐estimation method combinations do. The simulation results also show that increasing the sample size reduces the variability, and to some extent the bias, of item parameter estimates, whereas lower level of guessing and slip parameter is associated with higher quality item parameter estimation and classification accuracy.
1,4‐Thienodiazepine‐2,5‐diones via MCR (II): Scaffold Hopping by Gewald and Ugi‐Deprotection‐Cyclization Strategy
Authors: Huang Yijun , Dömling Alexander
Published: June 2010

A second scaffold of 1,4‐thienodiazepine‐2,5‐diones was discovered and is synthetically accessible from Gewald 2‐aminothiophenes via Ugi‐Deprotection‐Cyclization (UDC) strategy. This approach yielded hybrid peptidomimetic diazepine structures with six points of diversity introduced from readily available starting materials. A virtual compound library (N = 50 000) was generated and evaluated for chemical space distribution and drug‐like properties.
A 90‐D Toxicity Study of Monascus‐Fermented Products Including High Citrinin Level
Authors: Lee Chun‐Hsien , Lee Chun‐Lin , Pan Tzu‐Ming
Published: June 2010

Abstract:  Monascus is one of the traditional fermentation fungi and has been used in many kinds of food for thousands of years. Although Monascus‐fermented red mold rice performs cholesterol‐lowering effects, blood pressure‐lowing effects, and antioxidant effects, another metabolite, nephrotoxic and hepatotoxic citrinin, causes the concerns for safety. Various citrinin concentrations (1, 2, 10, 20, and 200 ppm) in the red mold rice are, respectively, estimated for safe use in animal tests. According to the results of serum biochemistry assays of liver and kidney in each group, citrinin did not reveal any nephrotoxicity and hepatotoxicity. Furthermore, the results of histopathological slices of liver and kidney in each group did not show any significant differences from control histopathological findings. As a result, we presume that citrinin concentrations in Monascus‐fermented products within 200 ppm will not affect the functions of liver and kidney or cause any nephrotoxicity and hepatotoxicity. According to safety factor, it is proposed that 2 ppm citrinin in Monascus‐fermented products may be a safe concentration.
Improving the Stability of Probiotic Bacteria in Model Fruit Juices Using Vitamins and Antioxidants
Authors: Shah N.P. , Ding W.K. , Fallourd M.J. , Leyer G.
Published: June 2010

Abstract:  This study examined the survival of probiotic bacteria in a model fruit juice system. Three different strains of probiotic bacteria were used in this study: HOWARU Lactobacillus rhamnosus HN001, HOWARU Bifidobacterium lactis HN001, and Lactobacillus paracasei LPC 37. The probiotic bacteria were inoculated into model juice with various vitamins and antioxidants, namely white grape seed extract, green tea extract, vitamin B2, vitamin B3, vitamin B6, vitamin C, and vitamin E. The model juice without any additives was used as a control. Their viability was assessed on a weekly basis using plate count method. The model juice was made with sucrose, sodium citrate, citric acid powder, and distilled water and was pasteurized before use. Our findings showed that probiotic bacteria did not survive well in the harsh environment of the model fruit juice. However, the model juice containing vitamin C, grape extract, and green tea extract showed better survival of probiotic bacteria. The model juice containing grape seed extract, green tea extract, and vitamin C had the same initial population of 8.32 log CFU/mL, and at the end of the 6‐wk storage period it had an average viability of 4.29 log CFU/mL, 7.41 log CFU/mL, and 6.44 log CFU/mL, respectively. Juices containing all other ingredients tested had viable counts of <10 CFU/mL at the end of the 6‐wk storage period.
Effect of slice thickness on liver lesion detection and characterisation by multidetector CT
Authors: Smith JT , Hawkins RM , Guthrie JA , Wilson DJ , Arnold PM , Boyes S , Robinson PJ
Published: June 2010

The purpose of our study was to compare the effectiveness of 3.2 mm, 5 mm and 7.5 mm slice thicknesses in the detection and characterisation of liver lesions found on CT in patients with known or suspected malignant disease. 110 patients underwent portal phase imaging using four‐slice MDCT. Two blinded observers independently read hard copy images at each slice thickness. The size and location of each lesion detected was recorded by each observer on a diagram of liver segmental anatomy. Each lesion was characterised as benign, malignant or indeterminate in nature. A diagnostic confidence score was allocated for each lesion on a scale of 1–4. The pathology or behaviour of lesions was assessed using surgery with intra‐operative ultrasound (IOUS) and histology, or interval imaging with MRI, CT, or sonography. 294 lesions were detected, 64 (22%) of which were malignant. Both observers detected significantly more lesions on the 3.2 mm versus 7.5 mm slice thickness (p < 0.0001). Both observers detected more malignant lesions on 3.2 mm and 5 mm slice thicknesses versus 7.5 mm. As slice thickness decreased there was a significant increase in the sensitivity of malignant lesion detection for observer 1 (p < 0.001) and borderline significance for observer 2 (p = 0.07). As slice thickness decreased the proportion of lesions characterised as indeterminate by both observers fell. With thinner slices, both detection and characterisation of liver lesions were improved. A slice thickness no greater than 5 mm should be used to maximise both detection and correct characterisation of liver lesions.
Diffusion‐weighted MRI for tumour volume delineation: Comparison with morphological MRI
Authors: Wolf G , Schindler S , Koch A , Abolmaali N
Published: June 2010

Diffusion‐weighted magnetic resonance imaging (dwMRI) is sensitive to tissue microstructure on the cellular level and may therefore help to define biological tumour subvolumes and add complementary information to morphology‐based cancer treatment protocols and therapy monitoring. The purpose of this study was therefore to evaluate the potential of dwMRI as compared with morphological MRI (mMRI) for tumour volume delineation using a nude rat human tumour xenograft model. Sixteen tumour‐bearing rats (10 H1299, six FaDu) were examined with mMRI (T2‐weighted true fast imaging with steady precession (TrueFISP), T1‐weighted fast low angle shot (FLASH), T2‐weighted dual echo steady state (DESS)) and echo‐planar dwMRI in a clinical scanner at 1.5 T. For each method, we compared tumour volume and intra‐ and inter‐observer variability of tumour outer edge delineation (disregarding intra‐tumoural structure) as well as tumour signal‐to‐noise ratio (SNR) and tumour‐to‐muscle contrast‐to‐noise ratio (CNR). Tumours were visualised with significantly higher SNR and CNR in dwMRI. Median tumour volumes as measured by dwMRI (3.5 cm3) and mMRI (TrueFISP: 3.3 cm3; FLASH: 3.3 cm3; DESS: 3.2 cm3) were not significantly different and significantly correlated. Related to partial volume effects, the intra‐ and inter‐observer variability of dwMRI (intra/inter: 12%/12%) was larger than for mMRI (TrueFISP: 4%/4%; FLASH: 5%/5%; DESS: 5%/5%). In conclusion, dwMRI allows tumour delineation with overall volume estimation comparable with mMRI approaches but slightly higher observer variability. Thus, besides tumour outline, it may potentially supplement morphology‐based therapy planning and monitoring with additional biological information.
Hypofractionated Whole‐Breast Radiotherapy: Impact on Departmental Waiting Times and Cost
Authors: Dwyer P , Hickey B , Burmeister E , Burmeister B
Published: June 2010

Conventionally fractionated breast radiation therapy is delivered over 5–6 weeks. Randomised evidence has shown that hypofractionated whole‐breast radiotherapy (HWBRT) over 3 weeks results in similar local control without increased toxicity. HWBRT is not standard practice in Australia for all eligible women. We examined the effect of using HWBRT (for eligible patients) on waiting lists and monetary costs. We identified factors associated with prescribing HWBRT. The Princess Alexandra Hospital Radiation Oncology Database was searched for all women with breast cancer treated with adjuvant radiotherapy in 2008. Included patients had undergone breast conserving surgery and had T1‐2N0 tumours with negative margins. Women with large breasts and those receiving nodal irradiation were excluded. The outcome evaluated was fractionation schedule. Patient, tumour and treatment factors associated with the use of HWBRT were examined. The impact on departmental resources and health‐care costs were calculated assuming the entire cohort received HWBRT. Two hundred seventy‐nine patients met the inclusion criteria. Sixty‐seven (24%) of these patients were treated with HWBRT. Compared with the conventionally fractionated breast radiation therapy group, the HWBRT group were older (median 69 vs. 54 years; P < 0.001) and more likely to have smaller tumours (12 mm vs. 15 mm; P = 0.02). Had all eligible patients received HWBRT an extra 14 patients each month could be treated and health‐care costs would be reduced by 24%. HWBRT was more frequently prescribed in older women with small tumours. More widespread use of HWBRT would allow significantly more patients to be treated each month with considerable cost savings.
Rectal dose reduction with IMRT for prostate radiotherapy
Authors: Hardcastle N , Davies A , Foo K , Miller A , Metcalfe PE
Published: June 2010

Dose escalation in radiation therapy has led to increased control rates with some clinical trial evidence that rectal toxicity may be reduced when using intensity‐modulated radiotherapy (IMRT) over 3D conformal radiotherapy (3DCRT) for dose‐escalated prostate radiotherapy. However, IMRT for prostate patients is not yet standard in many Australian radiation oncology centres. This study investigates dosimetric changes that can be observed between IMRT and 3DCRT in prostate radiotherapy. Fifteen patients were selected for analysis. Two target definitions were investigated – prostate‐only and prostate plus seminal vesicles (p + SVs). A five‐field 3DCRT and seven‐field IMRT plan were created for each patient and target definition. The planning target volume coverage was matched for both plans. Doses to the rectum, bladder and femoral heads were compared using dose volume histograms. The rectal normal tissue complication probabilities (NTCPs) were calculated and compared for the 3DCRT and IMRT plans. The delivery efficiency was investigated. The IMRT plans resulted in reductions in the V25, V50, V60, V70 and V75 Gy values for both the prostate‐only and p + SVs targets. Rectal NTCP was reduced with IMRT for three different sets of model parameters. The reductions in rectal dose and NTCP were much larger for the p + SVs target. Delivery of IMRT plans was less efficient than for 3DCRT plans. IMRT resulted in superior plans based on dosimetric and biological endpoints. The dosimetric gains with IMRT were greater for the more complex p + SVs target. The gains made came at the cost of decreased delivery efficiency.
Management of skin toxicity during radiation therapy: A review of the evidence
Authors: Kumar S , Juresic E , Barton M , Shafiq J
Published: June 2010

Acute skin toxicity occurs in the majority of the patients undergoing radical radiotherapy. While a variety of topical agents and dressing are used to ameliorate side effects, there is minimal evidence to support their use. The aims of this study were to systematically review evidence on acute skin toxicity management and to assess the current practices in ANZ. A systematic review of the literature was conducted on studies published between 1980 and 2008. A meta‐analysis was performed on articles on clinical trials reporting grade II or greater toxicity. Analyses were divided into breast (the most common site) and other sites. A survey of Radiation Oncology departments across ANZ was conducted to identify patterns of practices and compare these with the published evidence. Twenty‐nine articles were reviewed. Only seven articles demonstrated statistically significant results for management of side‐effects. These were for topical corticosteroids, hyaluronic acid, sucralfate, calendula, Cavilon cream (3M, St Paul, Minnesota, USA) and silver leaf dressing. Meta‐analysis demonstrated statistical significance for the prophylactic use of topical agents in the management acute toxicity. The survey of departments had a low response rate but demonstrated variation in skin care practices across ANZ. A considerable number of these practices were based only on anecdotal evidence. Lack of evidence in the literature for the care of radiation skin reactions was associated with variation in practice. Only a limited number of studies have demonstrated a significant benefit of specific topical agents. There is a need for objective and prospective recording of skin toxicity to collect meaningful comparative data on which to base recommendations for practice.
Finite-element modeling of depth and range dependent acoustic propagation in oceanic waveguides
Authors: Vendhan Chiruvai P. , Diwan Ganesh C. , Bhattacharyya Subrata K.
Published: June 2010

Finite-element models (FEMs) of ocean acoustic waveguides are capable of predicting the full wave solution including the effect of inhomogeneities and interfaces. However the method appears computationally feasible at present only for low to intermediate frequencies. The FEM discussed in this paper treats the radiation boundary condition involving multiple propagating modes using a penalty function approach. The effect of a point source has been represented as a pressure boundary condition on a small boundary surrounding the source. The FEM has been validated with a few examples of ideal waveguides. The FE results for a range and depth dependent parallel waveguide—an ASA benchmark problem [F. B. Jensen and C. M. Ferla, J. Acoust. Soc. Am. 87, 1499–1520 (1990)]—compare well with published results.
Enhancing the reconstruction of in-duct sound sources using a spectral decomposition method
Authors: Bravo Teresa , Maury Cédric
Published: June 2010

The characterization of in-duct acoustic source parameters for their use at the design stage, in virtual prototyping of the noise induced by fans and obstacles, is of great engineering importance. Conventional inverse approaches, such as the equivalent source method, offer accurate reconstruction results, but they require a large number of virtual sources or a suitable location of a few number of them. This paper proposes an alternative method that provides a cross-sectional imaging of the amplitude distribution of ducted sources, which does not depend on a prior adequate placement of equivalent sources, or on the degree of correlation between the real ones. The method is based on a full spectral formulation of the inverse problem, from which a theoretical stopping criterion is derived that provides a stable reconstruction of the unknown source distribution. Accurate and well-resolved imaging results of the axial acoustic velocity generated by wall-mounted drivers are obtained from either in-duct or wall-pressure measurements, acquired respectively without or with flow. The accuracy and the resolution of the retrieved source strength are significantly enhanced from an iterative modal decomposition of the pressure field, when imaging from data acquired respectively at large or small standoff distances to the source plane.
Echolocation signals of a beaked whale at Palmyra Atoll
Authors: Baumann-Pickering Simone , Wiggins Sean M. , Roth Ethan H. , Roch Marie A. , Schnitzler Hans-Ulrich , Hildebrand John A.
Published: June 2010

Acoustic recordings from Palmyra Atoll, northern Line Islands, central Pacific, showed upsweep frequency modulated pulses reminiscent of those produced by beaked whales. These signals had higher frequencies, broader bandwidths, longer pulse durations and shorter inter-pulse intervals than previously described pulses of Blainville’s, Cuvier’s and Gervais’ beaked whales [Zimmer et al. (2005). J. Acoust. Soc. Am. 117, 3919–3927; Johnson et al. (2006). J. Exp. Biol. 209, 5038–5050; Gillespie et al. (2009). J. Acoust. Soc. Am. 125, 3428–3433]. They were distinctly different temporally and spectrally from the unknown beaked whale at Cross Seamount, HI [McDonald et al. (2009). J. Acoust. Soc. Am. 125, 624–627]. Genetics on beaked whale specimens found at Palmyra Atoll suggest the presence of a poorly known beaked whale species. Mesoplodon sp. might be the source of the FM pulses described in this paper. The Palmyra Atoll FM pulse peak frequency was at 44 kHz with a −10 dB bandwidth of 26 kHz. Mean pulse duration was 355 μs and inter-pulse interval was 225 ms, with a bimodal distribution. Buzz sequences were detected with inter-pulse intervals below 20 ms and unmodulated spectra, with about 20 dB lower amplitude than prior FM pulses. These clicks had a 39 kHz bandwidth (−10 dB), peak frequency at 37 kHz, click duration 155 μs, and inter-click interval between 4 and 10 ms.
Active noise control using a steerable parametric array loudspeaker
Authors: Tanaka Nobuo , Tanaka Motoki
Published: June 2010

Arguably active noise control enables the sound suppression at the designated control points, while the sound pressure except the targeted locations is likely to augment. The reason is clear; a control source normally radiates the sound omnidirectionally. To cope with this problem, this paper introduces a parametric array loudspeaker (PAL) which produces a spatially focused sound beam due to the attribute of ultrasound used for carrier waves, thereby allowing one to suppress the sound pressure at the designated point without causing spillover in the whole sound field. First the fundamental characteristics of PAL are overviewed. The scattered pressure in the near field contributed by source strength of PAL is then described, which is needed for the design of an active noise control system. Furthermore, the optimal control law for minimizing the sound pressure at control points is derived, the control effect being investigated analytically and experimentally. With a view to tracking a moving target point, a steerable PAL based upon a phased array scheme is presented, with the result that the generation of a moving zone of quiet becomes possible without mechanically rotating the PAL. An experiment is finally conducted, demonstrating the validity of the proposed method.
Changes in consistency patterns of click frequency content over time of an echolocating Atlantic bottlenose dolphin
Authors: Ibsen Stuart D. , Au Whitlow W. L. , Nachtigall Paul E. , DeLong Caroline M. , Breese Marlee
Published: June 2010

Echolocation clicks were recorded from an Atlantic bottlenose dolphin Tursiops truncatus trained to discriminate frequency filtered phantom targets in 1998 and in 2004. These clicks showed consistency within their spectra intensity profiles but only in a certain band of frequencies. In 2004 almost all the clicks were consistent within the 0–42 kHz band regardless of the presented target or the click source level. This region corresponded with previous data showing that in 2004 the dolphin perceived frequencies only from within the 29–42 kHz band during echolocation. Above 42 kHz the consistency was lost. In 1998 the consistent region was found only in the 90–100 kHz band showing a shift had occurred with time. This suggests the dolphin’s echolocation strategy for these discrimination tasks centered on the use of clicks with the same controlled standard frequency content in a certain frequency band to investigate different targets. This consistent region shifted over time to maintain maximum signal to noise ratio of the echoes given certain changing limitations to the echolocation system. The shift in consistency over time indicates these consistent regions were not simply artifacts of click production but rather an active control of frequency content.
Acoustic scattering from a solid aluminum cylinder in contact with a sand sediment: Measurements, modeling, and interpretation
Authors: Williams Kevin L. , Kargl Steven G. , Thorsos Eric I. , Burnett David S. , Lopes Joseph L. , Zampolli Mario , Marston Philip L.
Published: June 2010

Understanding acoustic scattering from objects placed on the interface between two media requires incorporation of scattering off the interface. Here, this class of problems is studied in the particular context of a 61 cm long, 30.5 cm diameter solid aluminum cylinder placed on a flattened sand interface. Experimental results are presented for the monostatic scattering from this cylinder for azimuthal scattering angles from 0° to 90° and frequencies from 1 to 30 kHz. In addition, synthetic aperture sonar (SAS) processing is carried out. Next, details seen within these experimental results are explained using insight derived from physical acoustics. Subsequently, target strength results are compared to finite-element (FE) calculations. The simplest calculation assumes that the source and receiver are at infinity and uses the FE result for the cylinder in free space along with image cylinders for approximating the target/interface interaction. Then the effect of finite geometries and inclusion of a more complete Green’s function for the target/interface interaction is examined. These first two calculations use the axial symmetry of the cylinder in carrying out the analysis. Finally, the results from a three dimensional FE analysis are presented and compared to both the experiment and the axially symmetric calculations.
Exploring the benefit of auditory spatial continuity
Authors: Best Virginia , Shinn-Cunningham Barbara G. , Ozmeral Erol J. , Kopčo Norbert
Published: June 2010

Continuity of spatial location was recently shown to improve the ability to identify and recall a sequence of target digits presented in a mixture of confusable maskers [Best et al. (2008). Proc. Natl. Acad. Sci. U.S.A. 105, 13174–13178]. Three follow-up experiments were conducted to explore the basis of this improvement. The results suggest that the benefits of spatial continuity cannot be attributed to (a) the ability to plan where to direct attention in advance; (b) freedom from having to redirect attention across large distances; or (c) the challenge of filtering out signals that are confusable with the target.
Discovery of the Holotype of Cyathospongia(?) eozoica Matthew, a supposed Precambrian sponge from Saint John, New Brunswick
Authors: Miller Randall F.
Published: June 2010

Discovery of the holotype of the supposed sponge Cyathospongia(?) eozoica Matthew in the collections of the New Brunswick Museum completes a search for two doubtful Precambrian "sponges" described by Matthew almost a century ago. The organic nature of C.(?) eozoica had been questioned almost since its publication in 1890, but the specimen had been inaccessible. Examination of the holotype of C.(?) eozoica suggests the "spicules" from the Green Head Group of Saint John are probably a boxwork-like weathering pattern and are not organic.
Hot spots, magma underplating, and modification of continental crust
Authors: Fyfe W.S.
Published: June 2010

Most common mantle-derived magmas have densities at Moho pressures that exceed the density of average continental crust. Thus, unless the crust is tightly coupled with the mantle, many such magmas should penetrate at or near the Moho interface. The scale of such a phenomenon can be impressive; recent hot spots may have perturbed more than 5% of the planet's surface. The details of the process will depend on the ease of melting of the base of continents.Underplating can explain continental construction from below; Moho structures, or lack thereof; delamination of the continental basement; partial subduction and density cleaning of crust; the formation of massive anorthosite complexes; and major changes of elevation of continental blocks. In the thermally turbulent Archean, the very dense and hot komatiite magmas must have had even more profound influences.Modern studies of the subduction process show that the mantle must be heterogeneous and that volatiles can be carried to great depths in significant volumes.
Postcollisional cooling of the Penokean orogen in east-central Minnesota
Authors: Holm Daniel K. , Holst Timothy B. , Lux Daniel R.
Published: June 2010

New 40Ar/39Ar thermochronologic data from the internal zone of the Penokean orogen in east-central Minnesota indicate rapid cooling from mid-crustal temperatures. Early Proterozoic metamorphosed cover rocks yield concordant hornblende and biotite plateau ages of ~ 1755 Ma. Underlying Archean basement gneiss yields concordant muscovite and biotite plateau ages of ~ 1705 Ma. These are some of the oldest cooling ages recorded in rocks buried during the 1830–1860 Ma Penokean collisional orogeny. Cooling was coeval with regional rhyolitic volcanism and granite emplacement, suggesting a period of tectonic activity in this region during mid to late 1700 Ma. Based on similarities with Phanerozoic extensional regimes, we suggest, preliminarily, that these data might be explained by a previously unrecognized major extensional episode in the Lake Superior region.
Petroleum exploration model for the Queen Charlotte Basin area, offshore British Columbia
Authors: Lyatsky Henry V. , Haggart James W.
Published: June 2010

A potential oil-bearing region lies on the west coast of Canada, in the Queen Charlotte Basin area. Upper Triassic – Lower Jurassic source and Cretaceous reservoir rocks are capped by thick Tertiary volcanic and sedimentary strata. The traps are large block structures, and oil generation and migration took place principally in the Tertiary.Previous hypotheses of Queen Charlotte Basin evolution assumed high regional Tertiary heat flow and large tectonic extension; older rocks would have been overheated, and their oil destroyed. New data largely nullify such an interpretation. Miocene positive thermal anomalies were caused by magmatism, hence were local, and Mesozoic rocks may have retained their petroleum prospects. Regional structural style of the area has been dominated by repeated movements of fault-bounded crustal blocks since the Late Jurassic, and the structure of the Cenozoic basin was inherited largely from this older template.The new interpretation of the geologic evolution of the region permits a fresh assessment of its petroleum potential: Cretaceous strata beneath Queen Charlotte Sound are a prime exploration target. Caution is recommended when quantitative basin-formation models are applied to oil exploration; the best exploration model is one that incorporates the maximum geological and geophysical data.
Ice-sheet dynamics and subglacial meltwater regime inferred from form and sedimentology of glaciofluvial systems: Victoria Island, District of Franklin, Northwest Territories
Authors: Brennand T. A. , Sharpe D. R.
Published: June 2010

On Victoria Island, tunnel channels, eskers, and associated fans and extended deposits together constitute channelized glaciofluvial systems. Flutes and drumlinoid ridges, interpreted as residuals left by erosive, catastrophic, subglacial meltwater sheet flows, lie adjacent to these systems. One tunnel channel is described in detail. It exhibits deep scours, a discontinuous thalweg, sculpted margins, and flutes on the downflow side of one wall, features indicative of complex flow and possibly several flow events. The tunnel channel is interpreted as the product of erosion by catastrophic, subglacial meltwater flow in a combined ice – substrate (R/N) channel.Esker sediments and morphology are used to infer details of the depositional environment and meltwater regime. A continuous esker with fans and extended deposits records seasonally controlled discharge events through an R-channel. These features may also suggest a grounding-line environment, thin ice, and localized ice floatation events. Less well connected ridges also record seasonally controlled meltwater rhythms and were produced within a thinning and stagnating ice mass; the depositional environment may have been in a subglacial R-channel or an ice-walled reentrant.Differences in the drainage system associated with each glaciofluvial landform, and temporal disconnection between tunnel channel and esker formation, is also suggested by possible paleoflow reversals between inferred catastrophic and seasonally controlled drainage phases. Changes in ice-sheet profiles between events may have been responsible.
Paleoecology and age of the Flitaway and Isortoq interglacial deposits, north-central Baffin Island, Northwest Territories, Canada
Authors: Morgan Alan V. , Kuc Marian , Andrews John T.
Published: June 2010

Peats and woody-detrital deposits at two localities close to the Barnes Ice Cap at approximately 70°N contain insect faunas and mosses that indicate that these sites were situated close to tree line during the period of deposition. Modern tree line occurs some 1325 km (820 mi) to the south and southwest of these sites. Attempts to provide numeric ages based on the U-series of woody fragments were not successful. Although it has been assumed in the past that these peats were laid down during the last interglaciation, the inferred paleoclimatic conditions based on the insect faunas and plant remains suggest a substantially older (possible late Tertiary to mid Quaternary) age. The Flitaway and Isortoq sites probably had an annual average temperature at the time of deposition which was between −8 and −9 °C, i.e., about 4 – 5 °C warmer than today. Such information is important to calibrate and check global climatic models that predict substantial high-latitude greenhouse-gas warming.
Paleomagnetism of the Pine Point Zn–Pb deposits
Authors: Symons D. T. A. , Pan Hairu , Sangster D. F. , Jowett E. C.
Published: June 2010

The Pine Point Zn–Pb deposits are Mississippi Valley-type (MVT) deposits in Middle Devonian dolostone of the Pine Point Formation. The median natural remanent magnetization intensity from 509 specimens from 40 sites is 3.6 × 10−5 A/m. This intensity is an order of magnitude lower than most MVT deposits and is close to the sensitivity of the cryogenic magnetometer, so only the stronger specimens could be analysed paleomagnetically. Isothermal remanent magnetization testing of ores, host rocks, and monomineralic specimens shows that single domain to pseudosingle domain magnetite in sphalerite is the main remanence carrier; magnetite in galena is the next most significant carrier. In contrast, barren dolostone, limestone, and calcite crystals have a much weaker remanence. Using less stringent criteria than is conventional, 17 acceptable site mean remanence directions were determined. Remagnetization circle data indicate that many of the poorly defined sites retain a reversed but nonisolated characteristic remanence. Of the 17 means, 8 form a coherent cluster, the A component, with a mean direction of D = 339°, I = 78° (α95 = 7°, k = 62), giving a pole position of 79°N, 197°E (α95 = 13°). The A pole indicates with > 95%confidence that the MVT ores at Pine Point are Late Cretaceous to Eocene in age, with a mid-Late Cretaceous to Paleocene age (84–58 Ma) being most likely. The dolostone host rocks were remagnetized at the same time. It is concluded that the A component, carried mainly by sphalerite and galena, was formed during the Laramide orogeny (97–58 Ma) when tectonic uplift forced Zn–Pb-rich basinal brines out of the Western Canada sedimentary basin into the Presqu'ile barrier reef on the adjacent foreland shelf.
Cretaceous Coast Belt paleomagnetic data from the Spetch Creek pluton, British Columbia: evidence for the "tilt and moderate displacement" model
Authors: Vandall T. A.
Published: June 2010

Well-grouped stable magnetizations have been isolated at 14 of 20 sites sampled from the Spetch Creek pluton. The single-polarity primary magnetization directed at D = 026.2°, I = 73.5° (α95 = 4.4°, paleolatitude 59 ± 7°N, paleopole 73°N, 078°W, A95 = 7°) was acquired around 88 Ma during the Cretaceous normal polarity superchron (118–84 Ma). This direction is discordant from the expected mid-Cretaceous direction (D = 332.5°, I = 75.1°) for North America. The difference could be caused by one of two end member models: the all-tilt model requires a 15° east-side-up tilt about a horizontal axis striking 353°, and the displacement–rotation model requires 330 ± 770 km of northward displacement combined with 54 ± 14° of clockwise rotation. Regardless, this result provides a negative test of the Baja British Columbia model, which requires ~ 2400 km of northward displacement.A review of previously observed mid-Cretaceous magnetizations from the Coast Belt, which are also discordant, indicates that they exhibit common characteristics, although their discordance is not uniform. Assuming that present horizontal approximates paleohorizontal, post-mid-Cretaceous latitudinal displacements inferred from individual results vary between 330 and 3500 km northwards. Relative rotations about vertical axes vary between 17 and 57° clockwise. Such variation cannot be accounted for by the displacement and rotation of a superterrane as a whole. Recent studies emphasize that many of the intrusions have probably been locally tilted. Consistent with known geology, these discordant poles are best explained by the "tilt and moderate displacement" model. This model invokes moderate (500–1000 km) post-mid-Cretaceous northward displacement of the amalgamated Insular, Coast, and Intermontane terranes west of the major dextral Canadian Cordilleran fault systems, combined with variable local block tilting east- and northeast-side-up. Northward displacement was driven by Kula and (or) Farallon – North American plate interactions from 90 to 56 Ma. Tilting is most likely due to a combination of northeast–southwest compression, differential uplift, and extension.
MATHEMATICAL ANALYSIS OF A SAINT-VENANT MODEL WITH VARIABLE TEMPERATURE
Authors: GIOVANGIGLI VINCENT , TRAN BINH
Published: June 2010

We investigate the derivation and the mathematical properties of a Saint-Venant model with an energy equation and with temperature-dependent transport coefficients. These equations model shallow water flows as well as thin viscous sheets over fluid substrates like oil slicks, atlantic waters in the Strait of Gilbraltar or float glasses. We exhibit an entropy function for the system of partial differential equations and by using the corresponding entropic variable, we derive a symmetric conservative formulation of the system. The symmetrized Saint-Venant quasilinear system of partial differential equations is then shown to satisfy the nullspace invariance property and is recast into a normal form. Upon establishing the local dissipative structure of the linearized normal form, global existence results and asymptotic stability of equilibrium states are obtained. We finally derive the Saint-Venant equations with an energy equation taking into account the temperature-dependence of transport coefficients from an asymptotic limit of a three-dimensional model.
DEFORMED SPECIAL RELATIVITY WITH AN ENERGY BARRIER OF A MINIMUM SPEED
Authors: NASSIF CLÁUDIO
Published: June 2010

This paper aims to introduce a new principle of symmetry in the flat space–time by means of the elimination of the classical idea of rest, and by including a universal minimum limit of speed in the quantum world. Such a limit, unattainable by the particles, represents a preferred inertial reference frame associated with a universal background field that breaks Lorentz symmetry. So there emerges a new relativistic dynamics where a minimum speed forms an inferior energy barrier. One of the interesting implications of the existence of such a minimum speed is that it prevents the absolute zero temperature for an ultracold gas, according to the third law of thermodynamics. So we will be able to provide a fundamental dynamical explanation for the third law by means of a connection between such a phenomenological law and the new relativistic dynamics with a minimum speed.
PROPAGATING COMBUSTION MODES OF THE NEUTRON-TO-STRANGE-MATTER CONVERSION: THE ROLE OF INSTABILITIES
Authors: HORVATH J. E.
Published: June 2010

We discuss the propagation of the hypothetical "combustion" n → SQM in a dense stellar environment. We address the instabilities affecting the flame and a present new results of application to the turbulent regime. The acceleration of the flame, the possible transition to the distributed regime and a further deflagration-to-detonation mechanism are addressed. As a general result, we conclude that the burning happens in (at least) either the turbulent Rayleigh–Taylor or the distributed regime, but not in the laminar regime. In both cases the velocity of the conversion of the star is several orders of magnitude larger than u lam , making the latter irrelevant in practice for this problem. A transition to a detonation is by no means excluded; actually, it seems to be favored by the physical setting, but a definitive answer would need a full numerical simulation.