bluuebunny/crossref_metadata_2025 huggingface dataset:
Acoustically induced streaming flows near a model cod otolith and their potential implications for fish hearing
Authors: Kotas Charlotte W. , Rogers Peter H. , Yoda Minami
Published: August 2011

The ears of fishes are remarkable sensors for the small acoustic disturbances associated with underwater sound. For example, each ear of the Atlantic cod (Gadus morhua) has three dense bony bodies (otoliths) surrounded by fluid and tissue, and detects sounds at frequencies from 30 to 500 Hz. Atlantic cod have also been shown to localize sounds. However, how their ears perform these functions is not fully understood. Steady streaming, or time-independent, flows near a 350% scale model Atlantic cod otolith immersed in a viscous fluid were studied to determine if these fluid flows contain acoustically relevant information that could be detected by the ear’s sensory hair cells. The otolith was oscillated sinusoidally at various orientations at frequencies of 8–24 Hz, corresponding to an actual frequency range of 280–830 Hz. Phase-locked particle pathline visualizations of the resulting flows give velocity, vorticity, and rate of strain fields over a single plane of this mainly two-dimensional flow. Although the streaming flows contain acoustically relevant information, the displacements due to these flows are likely too small to explain Atlantic cod hearing abilities near threshold. The results, however, may suggest a possible mechanism for detection of ultrasound in some fish species.
Study on the applicability of instrumental measures for black-box evaluation of static feedback control in hearing aids
Authors: Madhu N. , Wouters J. , Spriet A. , Bisitz T. , Hohmann V. , Moonen M.
Published: August 2011

Presented is a report on black-box evaluation of feedback control systems for commercial hearing aids. The aim of the study is to examine the ability of existing instrumental measures to quantify the performance of the feedback control system in black-box settings and on realistic signals, when more than one element of the signal processing chain may be active (compression, noise suppression, microphone directionality, etc.). The evaluation is carried out on 6 different hearing aids and for 10 measures. Thereby it is possible to see which measure is best suited to measuring which specific characteristic of the feedback control system, and serves as a beginning for conducting perceptual tests. The study uses static (but variable) feedback paths and is based on signals recorded from the in-ear microphone of an artificial head, on which the hearing instruments are mounted.
Sequential streaming due to manipulation of interaural time differences
Authors: Stainsby Thomas H. , Füllgrabe Christian , Flanagan Helen J. , Waldman Sarah K. , Moore Brian C. J.
Published: August 2011

The effect of apparent spatial location on sequential streaming was investigated by manipulating interaural time differences (ITDs). The degree of obligatory stream segregation was inferred indirectly from the threshold for detecting a rhythmic irregularity in an otherwise isochronous sequence of interleaved “A” and “B” tones. Stimuli were bandpass-filtered harmonic complexes with a 100-Hz fundamental. The A and B tones had equal but opposite ITDs of 0, 0.25, 0.5, 1, or 2 ms and had the same or different passbands. The passband ranges were 1250–2500 Hz and 1768–3536 Hz in experiment 1, and 353–707 Hz and 500–1000 Hz in experiment 2. In both experiments, increases in ITD led to increases in threshold, mainly when the passbands of A and B were the same. The effects were largest for ITDs above 0.5 ms, for which rhythmic irregularities in the timing of the A or B tones alone may have disrupted performance. It is concluded that the differences in apparent spatial location produced by ITD have only weak effects on obligatory streaming.
Isolating mechanisms that influence measures of the precedence effect: Theoretical predictions and behavioral tests
Authors: Xia Jing , Shinn-Cunningham Barbara
Published: August 2011

This study tests how peripheral auditory processing and spectral dominance impact lateralization of precedence effect (PE) stimuli consisting of a pair of leading and lagging clicks. Predictions from a model whose parameters were set from established physiological results were tested with specific behavioral experiments. To generate predictions, an auditory nerve model drove a binaural, cross correlation computation whose outputs were summed across frequency using weightings derived from past physiological studies. The model predicted that lateralization (1) depends on stimulus center frequency and the inter-stimulus delay (ISD) between leading and lagging clicks for narrowband clicks and (2) changes differently with lead click level for different ISDs. Behaviorally, subjects lateralized narrowband and wideband click pairs whose stimulus parameters were chosen based on modeling results to test how peripheral processing and frequency dominance contribute to lateralization of PE stimuli. Behavioral results (including unique measures with the lead attenuated relative to the lag) suggest that peripheral interactions between leading and lagging clicks on the basilar membrane and strong weighting of cues around 750 Hz influence lateralization of paired clicks with short ISDs. When combined with auditory nerve adaptation, which emphasizes onset information, lateralization of PE click pairs with a short ISD can be well predicted.
Semicylindrical acoustic transducer from a dielectric elastomer film with compliant electrodes
Authors: Sugimoto Takehiro , Ono Kazuho , Ando Akio , Morita Yuichi , Hosoda Kosuke , Ishii Daisaku
Published: August 2011

A semicylindrical acoustic transducer was constructed using a dielectric elastomer film with compliant electrodes that is an electroactive polymer composed of a polyurethane elastomer base and polyethylene dioxythiophene/polystyrene sulfonate electrodes. The use of this dielectric elastomer is advantageous because polyurethane is a common material that keeps its shape without any rigid frame. Because the dielectric elastomer films are essentially incompressible, electric-field-induced thickness changes are usually translated into much larger changes of the film area and side length. Here it is proposed that this change in side length can be utilized for sound generation when the film is bent into a semicylindrical shape. Accordingly, a semicylindrical acoustic transducer was fabricated using a film of thickness of 300 μm and its acoustic characteristics were investigated. The transducer can be operated at low applied voltages by reducing the film thickness, as long as the film is thick enough to generate sufficient force to overcome sound radiation impedance. The second harmonic distortion of the transducer was also investigated as a function of the ratio of the direct current bias voltage to the alternating current audio signal amplitude.
Computation of acoustic absorption in media composed of packed microtubes exhibiting surface irregularity
Authors: Kulpe Jason A. , Lee Chang-Yong , Leamy Michael J.
Published: August 2011

A multi-scale homogenization technique and a finite element-based solution procedure are employed to compute acoustic absorption in smooth and rough packed microtubes. The absorption considered arises from thermo-viscous interactions between the fluid media and the microtube walls. The homogenization technique requires geometric periodicity, which for smooth tubes is invoked using the periodicity of the finite element mesh; for rough microtubes, the periodicity invoked is that associated with the roughness. Analysis of the packed configurations, for the specific microtube radii considered, demonstrates that surface roughness does not appreciably increase the overall absorption, but instead shifts the peaks and values of the absorption curve. Additionally, the effect of the fluid media temperature on acoustic absorption is also explored. The results of the investigation are used to make conclusions about tailored design of acoustically absorbing microtube-based materials.
Modeling and validation of polyurethane based passive underwater acoustic absorber
Authors: Jayakumari V. G. , Shamsudeen Rahna K. , Ramesh R. , Mukundan T.
Published: August 2011

The acoustic behavior of an acoustically transparent polyurethane and an interpenetrating polymer network of polyurethane with polydimethyl siloxane were studied using dynamic mechanical analysis, finite element modeling, and experimental evaluation of acoustic properties in a water-filled pulse tube setup. Dynamic mechanical measurements in the temperature range −50 °C to +70 °C were carried out, and the data were used for time temperature superposition to generate material behavior at high frequencies. These inputs were used for modeling the acoustic behavior of these materials using atila, which is a commercial finite element code, capable of computing transmission and reflection characteristics of materials. From this data, absorption characteristics were computed. The results were compared with the experimental results obtained using a water-filled pulse tube facility.
Perception of interrupted speech: Cross-rate variation in the intelligibility of gated and concatenated sentences
Authors: Shafiro Valeriy , Sheft Stanley , Risley Robert
Published: August 2011

Temporal constraints on the perception of variable-size speech fragments produced by interruption rates between 0.5 and 16 Hz were investigated by contrasting the intelligibility of gated sentences with and without silent intervals. Concatenation of consecutive speech fragments produced a significant decrease in intelligibility at 2 and 4 Hz, while having little effect at lower and higher rates. Consistent with previous studies, these findings indicate that (1) syllable-sized intervals associated with intermediate-rate interruptions are more susceptible to temporal distortions than the longer word-size or shorter phoneme-size intervals and (2) suggest qualitative differences in underlying perceptual processes at different rates.
Propagation of two longitudinal waves in a cancellous bone with the closed pore boundary
Authors: Mizuno Katsunori , Nagatani Yoshiki , Yamashita Keisuke , Matsukawa Mami
Published: August 2011

Ultrasound propagation in cancellous bone (porous media) under the condition of closed pore boundaries was investigated. A cancellous bone and two plate-like cortical bones obtained from a racehorse were prepared. A water-immersion ultrasound technique in the MHz range and a three-dimensional elastic finite-difference time-domain (FDTD) method were used to investigate the waves. The experiments and simulations showed a clear separation of the incident longitudinal wave into fast and slow waves. The findings advance the evaluation of bones based on the two-wave phenomenon for in vivo assessment.
Adaptive projection method applied to three-dimensional ultrasonic focusing and steering through the ribs
Authors: Cochard E. , Aubry J. F. , Tanter M. , Prada C.
Published: August 2011

An adaptive projection method for ultrasonic focusing through the rib cage, with minimal energy deposition on the ribs, was evaluated experimentally in 3D geometry. Adaptive projection is based on decomposition of the time-reversal operator (DORT method) and projection on the “noise” subspace. It is shown that 3D implementation of this method is straightforward, and not more time-consuming than 2D. Comparisons are made between adaptive projection, spherical focusing, and a previously proposed time-reversal focusing method, by measuring pressure fields in the focal plane and rib region using the three methods. The ratio of the specific absorption rate at the focus over the one at the ribs was found to be increased by a factor of up to eight, versus spherical emission. Beam steering out of geometric focus was also investigated. For all configurations projecting steered emissions were found to deposit less energy on the ribs than steering time-reversed emissions: thus the non-invasive method presented here is more efficient than state-of-the-art invasive techniques. In fact, this method could be used for real-time treatment, because a single acquisition of back-scattered echoes from the ribs is enough to treat a large volume around the focus, thanks to real time projection of the steered beams.
The role of masker fringes for the detection of coherent tone pips
Authors: Richards Virginia M. , Shub Daniel E. , Carreira Eva Maria
Published: August 2011

Three experiments investigated the role of pre/post exposure to a masker in a detection task with complex, random, spectro-temporal maskers. In the first experiment, the masker was either continuously presented or pulsed on and off with the signal. For most listeners, thresholds were lower when the masker was continuously presented, despite the fact that there was more uncertainty about the timing of the signal. In the second experiment, the signal-bearing portion of the masker was preceded and followed by masker “fringes” of different durations. Consistent with the findings of Experiment 1, for some listeners shorter-duration fringes led to higher thresholds than long-duration fringes. In the third experiment, the masker fringe (a) preceded, (b) followed, or (c) both preceded and followed, the signal. Relative to the middle signal conditions, a late signal yielded lower thresholds and the early signal yielded higher thresholds. These results indicate that listeners can use features of an ongoing sound to extract an added signal and that listeners differ in the importance of pre-exposure for efficient signal extraction. However, listeners do not appear to perform this comparison retrospectively after the signal, potentially indicating a form of backward masking.
Boundary effects on backscattering by a solid aluminum cylinder: Experiment and finite element model comparisons (L)
Authors: La Follett Jon R. , Williams Kevin L. , Marston Philip L.
Published: August 2011

Backscattering of sound by a solid aluminum cylinder was measured in the free field and with the cylinder near a flat surface. The target was suspended just below the surface of a water tank to simulate some aspects of backscattering when resting on the seabed. Measurements were compared with predictions made by an approximate hybrid approach based on multiple two-dimensional finite element calculations and the use of images. Many of the spectral features present in the tank data were present in the model. Comparing numerical model predictions with experimental data serves to build credibility for the modeling approach and can assist in developing insight into the underlying physical processes.
Astronomical Perspectives for Young Children
Authors: Ödman-Govender Carolina J , Kelleghan Deirdre
Published: August 2011

Crowd-sourced efforts and online educational resources are able to multiply the impact of astronomy outreach and education.
Comment on “Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009”
Authors: Samanta Arindam , Costa Marcos H. , Nunes Edson L. , Vieira Simone A. , Xu Liang , Myneni Ranga B.
Published: August 2011

Zhao and Running (Reports, 20 August 2010, p. 940) reported a reduction in global terrestrial net primary production (NPP) from 2000 through 2009. We argue that the small trends, regional patterns, and interannual variations that they describe are artifacts of their NPP model. Satellite observations of vegetation activity show no statistically significant changes in more than 85% of the vegetated lands south of 70°N during the same 2000 to 2009 period.
Genome Sequence of Nitrosomonas sp. Strain AL212, an Ammonia-Oxidizing Bacterium Sensitive to High Levels of Ammonia
Authors: Yuichi Suwa , Norton Jeanette M. , Bollmann Annette , Klotz Martin G. , Stein Lisa Y. , Laanbroek Hendrikus J. , Arp Daniel J. , Goodwin Lynne A. , Chertkov Olga , Held Brittany , Bruce David , Detter J. Chris , Detter Janine C. , Tapia Roxanne , Han Cliff S.
Published: August 2011

Nitrosomonas
sp. strain AL212 is an obligate chemolithotrophic ammonia-oxidizing bacterium (AOB) that was originally isolated in 1997 by Yuichi Suwa and colleagues. This organism belongs to
Nitrosomonas
cluster 6A, which is characterized by sensitivity to high ammonia concentrations, higher substrate affinity (lower

K
m

), and lower maximum growth rates than strains in
Nitrosomonas
cluster 7, which includes
Nitrosomonas europaea
and
Nitrosomonas eutropha.
Genome-informed studies of this ammonia-sensitive cohort of AOB are needed, as these bacteria are found in freshwater environments, drinking water supplies, wastewater treatment systems, and soils worldwide.
Draft Genome Sequence of Shewanella sp. Strain HN-41, Which Produces Arsenic-Sulfide Nanotubes
Authors: Kim Dong-Hun , Jiang Shenghua , Lee Ji-Hoon , Cho Yong-Joon , Chun Jongsik , Choi Sang-Haeng , Park Hong-Seog , Hur Hor-Gil
Published: August 2011

The dissimilatory metal reducing bacterium
Shewanella
sp. strain HN-41 was first reported to produce novel photoactive As-S nanotubes via reduction of As(V) and S
2
O
3
2−
under anaerobic conditions. Here we report the draft genome sequence and annotation of strain HN-41.
Comparison of Two Nucleic Acid Amplification Assays, the Xpert MTB/RIF Assay and the Amplified Mycobacterium Tuberculosis Direct Assay, for Detection of Mycobacterium tuberculosis in Respiratory and Nonrespiratory Specimens
Authors: Teo Jeanette , Jureen Roland , Chiang Donald , Chan Douglas , Lin Raymond
Published: August 2011

We compared the performance of the Xpert MTB/RIF assay, a new real-time tuberculosis (TB) PCR test, with that of the Amplified Mycobacterium Tuberculosis Direct (MTD) assay using 162 respiratory and nonrespiratory specimens. Based on culture as the gold standard, the overall sensitivity and specificity for all sample types for the Xpert MTB/RIF assay were 90.9 and 89%, respectively, while for the MTD assay, the overall sensitivity and specificity were 97.3 and 87.1%, respectively. A higher proportion of total equivocal results were obtained for the MTD assay, at 10.5% (17/162), while the Xpert MTB/RIF assay generated 5.5% (9/162) of invalid reads.
Evaluation of the DiversiLab Typing Method in a Multicenter Study Assessing Horizontal Spread of Highly Resistant Gram-Negative Rods
Authors: Overdevest I. T. M. A. , Willemsen I. , Elberts S. , Verhulst C. , Rijnsburger M. , Savelkoul P. , Kluytmans J. A. J. W.
Published: August 2011

The worldwide prevalence of highly resistant Gram-negative rods (HR-GNR) is increasing rapidly. Reliable typing methods are needed to detect and control outbreaks and to monitor the effectiveness of infection control programs in endemic situations. In this study, we investigated the performance of the DiversiLab typing method in comparison with the amplified fragment length polymorphism (AFLP) typing method. Six hundred fifty-three HR-GNR isolates, which were obtained during a 6-month prospective survey in 18 Dutch hospitals, were typed by AFLP and DiversiLab. Subsequently, the sensitivity and specificity of DiversiLab were calculated, using AFLP as the reference method. In addition, results were compared by means of epidemiological linkage, and Cohen's kappa for agreement was calculated. DiversiLab considered significantly more isolates (275) to belong to a cluster than AFLP (198) (
P
< 0.001). In direct comparison, the sensitivity was 83.8%, and the specificity was 78.6%. When epidemiological linkage was included in the analysis, DiversiLab considered eight isolates as secondary cases, which were considered unique in AFLP. Only two secondary cases, according to AFLP, were missed by DiversiLab. This results in a kappa for agreement of 0.985. In daily practice, a typing method has to be used in combination with epidemiological information. When this was done, DiversiLab was shown to be a reliable method for the typing of HR-GNR. This, in combination with the ease of use and the speed, makes DiversiLab an appropriate method for screening in routine clinical practice. When a cluster is suspected and the consequences of these findings are substantial, a confirmatory analysis should be performed.
Genetic Heterogeneity in Clinical Isolates of Leishmania donovani from India
Authors: Srivastava Pankaj , Singh Toolika , Sundar Shyam
Published: August 2011

Genetic diversity within 45 Indian
Leishmania donovani
isolates was analyzed using seven genetic markers. While kinetoplast DNA (kDNA) analysis revealed 15 genotypes, 8 genotypes were obtained by analysis of other markers. In contrast to earlier reports, our data suggest that significant genetic polymorphisms exist in
L. donovani
strains in Bihar, India. Our results confirm the presence of 2 zymodemes in India.
Rapid Multiplexed Immunoassay for Simultaneous Serodiagnosis of HIV-1 and Coinfections
Authors: Lochhead Michael J. , Todorof Kathryn , Delaney Marie , Ives Jeffrey T. , Greef Charles , Moll Kevin , Rowley Keagan , Vogel Kurt , Myatt Chris , Zhang Xing-Quan , Logan Cathy , Benson Constance , Reed Sharon , Schooley Robert T.
Published: August 2011

Diagnosis of opportunistic infections in HIV-infected individuals remains a major public health challenge, particularly in resource-limited settings. Here, we describe a rapid diagnostic system that delivers a panel of serologic immunoassay results using a single drop of blood, serum, or plasma. The system consists of disposable cartridges and a simple reader instrument, based on an innovative implementation of planar waveguide imaging technology. The cartridge incorporates a microarray of recombinant antigens and antibody controls in a fluidic channel, providing multiple parallel fluorescence immunoassay results for a single sample. This study demonstrates system performance by delivering antibody (Ab) reactivity results simultaneously for multiple antigens of HIV-1,Treponema pallidum(syphilis), and hepatitis C virus (HCV) in a collection of clinical serum, plasma, and whole-blood samples. By plotting antibody reactivity (fluorescence intensity) for known positive and negative samples, empirical reactivity cutoff values were defined. The HIV-1 assay shows 100% agreement with known seroreactivity for a collection of 82 HIV Ab-positive and 142 HIV Ab-negative samples, including multiple samples with HCV and syphilis coinfection. The treponema-specific syphilis assay correctly identifies 67 of 68T. pallidumAb-positive and 100 of 102T. pallidumAb-negative samples, and the HCV assay correctly identifies 59 of 60 HCV Ab-positive and 120 of 121 HCV Ab-negative samples. Multiplexed assay performance for whole-blood samples is also demonstrated. The ability to diagnose HIV and opportunistic infections simultaneously at the point of care should lead to more effective therapy decisions and improved linkage to care.
Saksenaea erythrospora Infection following Combat Trauma
Authors: Hospenthal Duane R. , Chung Kevin K. , Lairet Kimberly , Thompson Elizabeth H. , Guarro Josep , Renz Evan M. , Sutton Deanna A.
Published: August 2011

Saksenaea erythrospora
is a newly described species of the order Mucorales which has not previously been reported as a cause of human infection. We report a fatal case of
S. erythrospora
invasive burn wound infection in a 26-year-old male injured during combat operations in Iraq.
Quantification of Clostridium difficile in Antibiotic-Associated-Diarrhea Patients
Authors: Naaber Paul , Štšepetova Jelena , Smidt Imbi , Rätsep Merle , Kõljalg Siiri , Lõivukene Krista , Jaanimäe Liis , Löhr Iren H. , Natås Olav B. , Truusalu Kai , Sepp Epp
Published: August 2011

Comparing culture- and non-culture-based methods for quantifying
Clostridium difficile
in antibiotic-associated-diarrhea patients, we found that the real-time PCR method correlated well with quantitative culture and was more sensitive. A positive association between the population levels of
C. difficile
and the presence of its toxins was found.
Fatal Outcome of Pandemic H1N1 2009 Influenza Virus Infection Is Associated with Immunopathology and Impaired Lung Repair, Not Enhanced Viral Burden, in Pregnant Mice
Authors: Marcelin Glendie , Aldridge Jerry R. , Duan Susu , Ghoneim Hazem E. , Rehg Jerold , Marjuki Henju , Boon Adrianus C. M. , McCullers Jonathan A. , Webby Richard J.
Published: August 2011

Pandemic A (H1N1) 2009 influenza virus (pH1N1) infection in pregnant women can be severe. The mechanisms that affect infection outcome in this population are not well understood. To address this, pregnant and nonpregnant BALB/c mice were inoculated with the wild-type pH1N1 strain A/California/04/09. To determine whether innate immune responses are associated with severe infection, we measured the innate cells trafficking into the lungs of pregnant versus nonpregnant animals. Increased infiltration of pulmonary neutrophils and macrophages strongly correlated with an elevated mortality in pregnant mice. In agreement with this, the product of nitric oxide (nitrite) and several cytokines associated with recruitment and/or function of these cells were increased in the lungs of pregnant animals. Surprisingly, increased mortality in pregnant mice was not associated with higher virus load because equivalent virus titers and immunohistochemical staining were observed in the nasal cavities or lungs of all mice. To determine whether exacerbated inflammatory responses and elevated cellularity resulted in lung injury, epithelial regeneration was measured. The lungs of pregnant mice exhibited reduced epithelial regeneration, suggesting impaired lung repair. Despite these immunologic alterations, pregnant animals demonstrated equivalent percentages of pulmonary influenza virus-specific CD8
+
T lymphocytes, although they displayed elevated levels of T-regulator lymphocytes (Tregs) in the lung. Also, pregnant mice mounted equal antibody titers in response to virus or immunization with a monovalent inactivated pH1N1 A/California/07/09 vaccine. Therefore, immunopathology likely caused by elevated cellular recruitment is an implicated mechanism of severe pH1N1 infection in pregnant mice.
Matrix Protein-Specific IgA Antibody Inhibits Measles Virus Replication by Intracellular Neutralization
Authors: Zhou Dihan , Zhang Yan , Li Qiaoli , Chen Yaoqing , He Benxia , Yang Jingyi , Tu Haobo , Lei Lei , Yan Huimin
Published: August 2011

Measles virus (MV) is still an imposing threat to public health. The matrix (M) protein has been shown not only to function as a structure block in the assembled MV virions, but also to regulate viral RNA synthesis, playing an important role in MV's replication and assembly. In the present study, we generated a panel of IgG monoclonal antibodies (MAbs) against M protein and successfully obtained one IgA MAb (5H7) from the IgG panel. Employing the polarized Vero cells grown in the two-chamber transwell model, we investigated whether M-specific 5H7 IgA MAb could suppress MV's replication and assembly. The data presented indicate that, while failing to show the activities of traditional neutralization and immune exclusion, M-specific IgA MAb was able to effectively inhibit viral replication by intracellular neutralization (78%), supporting the notion that the M protein is important for MV assembly and replication and implying that the M protein was an effective target antigen. The data also showed that MV had a long entry and assembly phase during viral replication, providing an extended window for IgA intervention. The colocalization of M proteins and M-specific 5H7 IgA MAbs demonstrated that the intracellular neutralization was due to the direct binding of the M-specific 5H7 IgA MAbs to the M proteins. In summary, the present study has added another example showing that IgA antibodies targeting internal viral antigens could proactively participate in mucosal immune protection by intracellular neutralization and has provided evidence that M protein might be included as a target antigen in future MV vaccine design.
Coreplication of the Major Genotype Group Members of Porcine Circovirus Type 2 as a Prerequisite to Coevolution May Explain the Variable Disease Manifestations
Authors: Khaiseb Siegfried , Sydler Titus , Zimmermann Dieter , Pospischil Andreas , Sidler Xaver , Brugnera Enrico
Published: August 2011

A member of the family
Circoviridae
, porcine circovirus type 2 (PCV2), is associated with postweaning multisystemic wasting syndrome (PMWS), a recent emerging disease worldwide. PCV2 is also found in clinically asymptomatic animals. This paradoxical finding makes the syndrome etiology challenging. We developed new assays to study PCV2 with links to syndrome etiology. For analysis, we used PCV2-infected tissues from subclinically infected and diseased piglets. We compared antigen- and PCV2 DNA-derived signals for tissue localization and intensity. Oligonucleotides were designed to the signature motif of the PCV2 capsid open reading frame to discriminate experimentally between PCV2 genotype groups by PCR,
in situ
hybridization (ISH), and fluorescence
in situ
hybridization (FISH). Unexpectedly, all PCV2-infected animals carried both PCV2a and PCV2b genotype group members. Using confocal microscopy, genotype single-cell infections and cell superinfections were visible. Additionally, we discriminated replicative DNA from total PCV2 DNA isoforms with FISH. This aided in our inquiry into cellular genotype-specific replication. Importantly, single-genotype-group replication was not observed. In infected cells with replicating virus, both genotype groups were equally present. These findings suggest PCV2 genotype group members relaxed replication regulation requirements and may even point to PCV2 replication cooperativity
in vivo
. These observations explain the readily seen PCV2 DNA recombinations and the high overall PCV2 genome plasticity. Hence, we suggest a novel mechanism of syndrome etiology that consists of a continuously changing PCV2 genome pool in hosts and pig herds, posing a constant challenge to the individual maturing immune system.
trans
-Repression of Protein Expression Dependent on the Epstein-Barr Virus Promoter Wp during Latency
Authors: Hughes David J. , Dickerson Carol A. , Shaner Marie S. , Sample Clare E. , Sample Jeffery T.
Published: August 2011

An ordered silencing of Epstein-Barr virus (EBV) latency gene transcription is critical for establishment of persistent infection within B lymphocytes, yet the mechanisms responsible and the role that the virus itself may play are unclear. Here we describe two B-cell superinfection models with which to address these problems. In the first, Burkitt lymphoma (BL) cells that maintain latency I, when superinfected, initially supported transcription from the common
EBNA
promoters Wp and Cp (latency III) but ultimately transitioned to latency I (Cp/Wp silent), an essential requirement for establishment of EBV latency
in vivo
. We used this model to test whether the early lytic-cycle gene
BHLF1
, implicated in silencing of the Cp/Wp locus, is required to establish latency I. Upon superinfection with EBV deleted for the
BHLF1
locus, however, we have demonstrated that
BHLF1
is not essential for this aspect of EBV latency. In the second model, BL cells that maintain Wp-restricted latency, a variant program in which Cp is silent but Wp remains active, sustained the latency III program of transcription from the superinfecting-virus genomes, failing to transition to latency I. Importantly, there was substantial reduction in Wp-mediated protein expression from endogenous EBV genomes, in the absence of Cp reactivation, that could occur independent of a parallel decrease in mRNA. Thus, our data provide evidence of a novel, potentially posttranscriptional mechanism for
trans
-repression of Wp-dependent gene expression. We suggest that this may ensure against overexpression of the EBV nuclear antigens (EBNAs) prior to the transcriptional repression of Wp in
cis
that occurs upon activation of Cp.
Naturally Occurring Antibodies in Humans Can Neutralize a Variety of Influenza Virus Strains, Including H3, H1, H2, and H5
Authors: Ohshima Nobuko , Iba Yoshitaka , Kubota-Koketsu Ritsuko , Asano Yoshizo , Okuno Yoshinobu , Kurosawa Yoshikazu
Published: August 2011

Influenza A viruses are classified into 16 subtypes according to the serotypes of hemagglutinin (HA). It is generally thought that neutralizing antibodies (Abs) are not broadly cross-reactive among HA subtypes. We examined the repertoire of neutralizing Abs against influenza viruses in humans. B lymphocytes were collected from donors by apheresis, and Ab libraries were constructed by using phage-display technology. Anti-HA clones were isolated by screening with H3N2 viruses. Their binding activity was examined, and four kinds of Abs showing broad strain specificity were identified from one donor. Two of the Abs, F045-092 and F026-427, were extensively analyzed. They neutralized not only H3N2 but also H1N1, H2N2, and H5N1 viruses, although the activities were largely varied. Flow cytometry suggested that they have the ability to bind to HA and HA1 artificially expressed on the cell surface. They show hemagglutination inhibition activity and do not compete with C179, an Ab thought to bind to the stalk region. F045-092 competes with Abs that recognize sites A and B for binding to HA. Furthermore, the serine at residue 136 in site A could be a part of the epitope. Thus, it is likely that F045-092 and F026-427 bind to a conserved epitope in the head region formed by HA1. Interestingly, while the

V
H
1

-
69
gene can encode MAbs against the HA stem that are group 1 specific, F045-092 and its relatives that recognize the head region also use

V
H
1

-
69
. The possible epitope recognized by these clones is discussed.
The Cryo-Electron Microscopy Structure of Feline Calicivirus Bound to Junctional Adhesion Molecule A at 9-Angstrom Resolution Reveals Receptor-Induced Flexibility and Two Distinct Conformational Changes in the Capsid Protein VP1
Authors: Bhella David , Goodfellow Ian G.
Published: August 2011

Caliciviridae
are small icosahedral positive-sense RNA-containing viruses and include the human noroviruses, a leading cause of infectious acute gastroenteritis and feline calicivirus (FCV), which causes respiratory illness and stomatitis in cats. FCV attachment and entry is mediated by feline junctional adhesion molecule A (fJAM-A), which binds to the outer face of the capsomere, inducing a conformational change in the capsid that may be important for viral uncoating. Here we present the results of our structural investigation of the virus-receptor interaction and ensuing conformational changes. Cryo-electron microscopy and three-dimensional image reconstruction were used to solve the structure of the virus decorated with a soluble fragment of the receptor at subnanometer resolution. In initial reconstructions, the P domains of the capsid protein VP1 and fJAM-A were poorly resolved. Sorting experiments led to improved reconstructions of the FCV–fJAM-A complex both before and after the induced conformational change, as well as in three transition states. These data showed that the P domain becomes flexible following fJAM-A binding, leading to a loss of icosahedral symmetry. Furthermore, two distinct conformational changes were seen; an anticlockwise rotation of up to 15° of the P domain was observed in the AB dimers, while tilting of the P domain away from the icosahedral 2-fold axis was seen in the CC dimers. A list of putative contact residues was calculated by fitting high-resolution coordinates for fJAM-A and VP1 to the reconstructed density maps, highlighting regions in both virus and receptor important for virus attachment and entry.
Born just a few weeks early: does it matter?
Authors: Boyle Jennifer D , Boyle Elaine M
Published: August 2011

Until recently, infants born at moderate preterm (32–33 weeks) and late preterm (34–36 weeks) gestations have gone largely unstudied. Since their outcomes were thought to be similar to those of infants born at 37 weeks and above, they have historically been managed in much the same way as infants born at term. However, accumulating data indicate that risks of morbidity and mortality are significantly greater in this group than previously believed. Since moderate and late preterm infants account for around 6% of all births, very large numbers of babies are potentially affected. Although their problems may be less obvious than those of extremely preterm infants, the population impact of long-term health and neurodevelopmental problems in this group will be substantial. This review summarises the current available literature, highlights gaps in knowledge and discusses the implications of late preterm birth for both clinical practice and research in the perinatal period and beyond.
What are the main research findings during the last 5 years that have changed my approach to clinical practice?
Authors: Poets Christian F
Published: August 2011

When asked to address the above question, findings that appeared to be among the most relevant included (1) interventions in the delivery room directed at supporting the physiological transition from intrauterine to extrauterine life rather than actively intervening in it; (2) recent data suggesting that keeping extremely low-gestational age neonates at a pulse oximeter saturation (SpO2) of 91–95% would increase their chances of survival compared with aiming for lower SpO2values; (3) using caffeine citrate in infants <1250 g with apnoea of prematurity improves neurodevelopmental outcome; (4) injecting antivascular epithelial growth factor into the vitreous seems to be an effective treatment for retinopathy of prematurity and (5) moderate hypothermia for perinatal hypoxic-ischaemic encephalopathy increases the likelihood of survival without neurological impairment. Here, data that support these recent changes in approach will be presented and discussed.
Remedies sought and obtained in healthcare complaints
Authors: Bismark Marie M , Spittal Matthew J , Gogos Andrew J , Gruen Russell L , Studdert David M
Published: August 2011

In the wake of adverse events, injured patients and their families have a complex range of needs and wants. The tort system, even when operating at its best, will inevitably fall far short of addressing them. In Australia and New Zealand, government-run health complaints commissions take a more flexible and expansive approach to providing remedies for patients injured by or disgruntled with care. Unfortunately, survey research has shown that many patients in these systems are dissatisfied with their experience. We hypothesised that an important explanation for this dissatisfaction is an ‘expectations gap’; discordance between what complainants want and what they eventually get out of the process. Analysing a sample of complaints relating to informed consent from the Commission in Victoria (Australia's second largest state, with 5.2 million residents), we found evidence of such a gap. One-third (59/189) of complainants who sought restoration received it; 1 in 5 complainants (17/101) who sought correction received assurances that changes had been or would be made to reduce the risk of others suffering a similar harm; and fewer than 1 in 10 (3/37) who sought sanctions saw steps taken to achieve this outcome initiated. We argue that bridging the expectations gap would go far toward improving patient satisfaction with complaints systems, and suggest several ways this might be done.
The ‘I’ of the beholder: studying the ‘self’ across the humanities and neuroscience
Authors: Pannese Alessia
Published: August 2011

Long debated within the humanistic tradition, the concept of ‘self’ has recently been embraced as a subject of investigation by cognitive neuroscience. Tracing parallels between ancient philosophical ideas and current-day scientific research on the ‘self’, the author proposes that contemporary knowledge based on empirical neuroscientific evidence may inform novel perspectives on—and draw inspiration from—notions grounded in ancient intuitions and traditionally falling within humanistic fields of enquiry. Further, the author suggests that the ‘self’, as a major object of philosophical and psychological enquiry, as well as a central component of human motivation, cognition, affect and social identity, is an inherently cross-disciplinary research topic, which, by virtue of its pervasive and defining presence in human existence, lends itself—and demands—to be approached both from scientific (objective) and phenomenological (subjective) vantage points. On this premise, the author proposes that the study of the ‘self’ provides both neuroscientists and humanists with a fertile ground for cross-disciplinary research, and with the challenge and the opportunity to rethink the relationship of science to knowledge.
Prevalence of owner‐reported behaviours in dogs separated from the litter at two different ages
Authors: Pierantoni L. , Albertini M. , Pirrone F.
Published: August 2011

The present study examined the prevalence of behaviours in dogs separated from the litter for adoption at different ages. Seventy adult dogs separated from their dam and littermates and adopted between the ages of 30 and 40 days were compared with 70 adult dogs that had been taken from the litter for adoption at two months. Owners were asked to complete a questionnaire eliciting information on whether their dog exhibited potentially problematic behaviours when in its usual environment. Binary logistic regression analysis was performed to investigate whether the age at which the dog was separated from the litter might predispose it to developing undesirable behaviours. The odds of displaying destructiveness, excessive barking, fearfulness on walks, reactivity to noises, toy possessiveness, food possessiveness and attention‐seeking were significantly greater for the dogs that had been removed from the litter earlier during the socialisation period. In addition, dogs purchased from a pet shop at 30 to 40 days of age were reported to exhibit some of the listed behaviours with a significantly higher frequency than dogs purchased from a pet shop at two months. No significant differences were observed with dogs obtained from other types of sources. The dogs in the youngest age group (18 to 36 months) had a higher probability of displaying destructiveness and tail chasing. These findings indicate that, compared with dogs that remained with their social group for 60 days, dogs that had been separated from the litter earlier were more likely to exhibit potentially problematic behaviours, especially if they came from a pet shop.
Menstrual cycle and oral contraceptives’ effects on growth hormone response to sprinting
Authors: Sunderland Caroline , Tunaley Victoria , Horner Fleur , Harmer Daniel , Stokes Keith A.
Published: August 2011

The present study examined the impact of the menstrual cycle and oral contraceptive (OC) use on the growth hormone response to nonmotorized treadmill sprinting. Nine monophasic OC users (21.5 ± 4.7 years old), and 8 normally menstruating women (NM; 21.4 ± 2.9 years old) participated in the study. Each participant completed 2 main trials, each consisting of an all-out 30-s treadmill sprint. The NM group performed one trial in the midfollicular phase (NM follicular) and one in the midluteal phase (NM luteal); the OC group’s trials occurred one week into the start of the pill-taking cycle and once during the week in which pills were not taken.Venous blood samples were analyzed for growth hormone, pH, lactate, glucose, and progesterone concentrations. Peak and mean power output did not differ between the groups or with menstrual phase, or between the OC-free and OC trials. Integrated growth hormone was greater in the OC group than in the NM group (p = 0.04) with no phase difference (p = 0.80, mean (SD); NM follicular: 421 (335) and NM luteal: 345 (304) vs. OC free: 737 (471) and OC: 758 (389) µg·L–1·90 min–1). Blood lactate was higher in the OC group than in the NM group (p = 0.007) and, conversely, pH was lower in the OC group (p = 0.01). These results demonstrate that OC users who take high-androgenicity pills have a higher growth hormone response to sprint running than do normally menstruating women.
Consumer perceptions of trans fats in 2009 show awareness of negative effects but limited concern regarding use in snack foods
Authors: Nasser Roseann , Cook Stephanie , Bashutski Megan , Hill Karen , Norton Darci , Coleman Jean , Walker Sharon , Charlebois Sylvain
Published: August 2011

The purpose of this study was to determine consumers’ perceptions of industrially produced trans fats. A cross-sectional study was conducted in Regina at 3 different grocery store chains located in 3 different regions. A 21-item survey was administered in English by 3 research assistants at the grocery stores over a 5-day period. Of 498 potential respondents who were approached, 211 completed the survey, for a 42% response rate. The majority of respondents were female and over 61 years of age. When respondents were asked if they looked for information on food packages while grocery shopping, none of the respondents indicated that they looked for trans fat on the food label. Ninety-six percent of respondents identified that trans fat is found in processed foods, whereas 42% of respondents incorrectly identified trans fat as being found in nonhydrogenated margarines. More female respondents self-reported that they had made dietary changes to decrease trans fat intake as compared with male respondents (p < 0.05). Those participants who made dietary changes to decrease trans fat intake had higher mean knowledge scores than did those who did not make changes (p < 0.043). Sixty-three percent of respondents indicated that they would not make dietary changes to their snack food selections even if their selections contained trans fat. Consumers know a little about trans fats and consider them to be a concern. However, consumers are reluctant to make dietary changes to limit these fats in their snack food selections.
Family meals and body mass index among adolescents: effects of gender
Authors: Goldfield Gary S. , Murray Marisa A. , Buchholz Annick , Henderson Katherine , Obeid Nicole , Kukaswadia Atif , Flament Martine F.
Published: August 2011

Family meals have been identified as a protective factor against obesity among youth. However, gender specificities with respect to the relationship between the frequency of family meals and body mass index (BMI) have not been investigated. The purpose of this study was to examine the relationship between the frequency of family meals and BMI in male and female adolescents, while controlling for potential confounding factors associated with BMI, such as parental education, adolescent’s age, and snack-food eating. Research participants were 734 male and 1030 female students (mean age, 14.12 years, SD = 1.62) recruited from middle schools and high schools in the capital region of Canada. Participants completed validated, self-report measures to assess the frequency of family meals and the risk factors associated with increased BMI, which was derived from objective measures of height and weight. After controlling for proposed confounding variables, a higher frequency of family meals was associated with lower BMI in females, but not in males. A Z-transformation test of the homogeneity of adjusted correlation coefficients showed a significant trend (p = 0.06), indicating that the relationship between family meals and BMI is stronger in females than males, consistent with our regression analyses. Our findings suggest that eating together as a family may be a protective factor against obesity in female adolescents, but not in male adolescents. Findings from this study have important implications for parents and health care practitioners advocating for more frequent family meals as part of a comprehensive obesity prevention and treatment program for female adolescents.