bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulated neural processing of Western harmony in folk musicians
Authors: Brattico Elvira , Tupala Tiina , Glerean Enrico , Tervaniemi Mari
Published: May 2013

A chord deviating from the conventions of Western tonal music elicits an early right anterior negativity (ERAN) in inferofrontal brain regions. Here, we tested whether the ERAN is modulated by expertise in more than one music culture, as typical of folk musicians. Finnish folk musicians and nonmusicians participated in electroencephalography recordings. The cadences consisted of seven chords. In incongruous cadences, the third, fifth, or seventh chord was a Neapolitan. The ERAN to the Neapolitans was enhanced in folk musicians compared to nonmusicians. Folk musicians showed an enhanced P3a for the ending Neapolitan. The Neapolitan at the fifth position was perceived differently and elicited a late enhanced ERAN in folk musicians. Hence, expertise in more than one music culture seems to modify chord processing by enhancing the ERAN to ambivalent chords and the P3a to incongruous chords, and by altering their perceptual attributes.
The effect of acute mental stress on limb vasodilation is unrelated to total peripheral resistance
Authors: Paine Nicola J. , Ring Christopher , Bosch Jos A. , McIntyre David , Veldhuijzen van Zanten Jet J. C. S.
Published: May 2013

Mental stress can trigger myocardial infarction, with poor vascular responses to stress implicated as a pathway. Vascular stress reactivity can be assessed by different methods, such as total peripheral resistance (TPR) and forearm blood flow (FBF). Little is known about how these vascular assessments are linked. This was examined in two separate studies. Healthy men (Study 1: N = 29, Study 2: N = 23) completed rest and mental arithmetic (Study 1: 8 min, Study 2: 16 min). In both studies, heart rate, mean arterial pressure, and FBF increased in response to stress. In Study 1, no changes in TPR were seen, but Study 2 found stress‐induced increases in TPR. FBF was not linked to TPR at any time (all ps > .05). It appears that limb vasculature and TPR responses to stress do not give the same information about impairments of the vasculature. These findings are relevant to the interpretation of prior research findings and the design of future studies on stress and vascular responses.
Lessons from Leadership Theory and the Contemporary Challenges of Leaders
Authors: Van Wart Montgomery
Published: May 2013

Leadership theories and the academic literature can sometimes seem difficult for practitioners to understand because of complex conceptualizations, obscure terms, and its enormousness. Yet taken as a whole, the literature makes a great deal of sense and has much to offer. Indeed, the truths are often quite simple, elegant, and straightforward. The purpose of this article is to review the major findings of the organizational leadership literature and to identify the important overarching insights, specifically those of particular importance to today's leaders in administrative positions in the public sector, where an evolving context constantly reconfigures age‐old challenges.
How German Geopolitics Passed Through the Netherlands, 1920–1945: A Case Study in the Geography of one of Geography's ‘Projects’
Authors: van der Wusten Herman , de Pater Ben
Published: May 2013

German geopolitics emerged from the early 1920s. It was noticed in the Netherlands but not broadly embraced. In public discourse the term ‘geopolitics’ was hardly ever used between the First and Second World Wars but it became a bit more common with the looming threat of a second war and during the German occupation. Meanwhile Dutch geographers took note of the efforts of Haushofer and his circle. Around 1930, their initial reaction to this project took various forms – constructive criticism, co‐operation and indignant dismissal – but the attention waned over the decade. During the occupation Nazi‐friendly geographers discussed the launching of a new geopolitics. The generally shared Dutch preference for aloofness, neutrality and recourse to international law as the way to approach international relations precluded the formation of a large, responsive public for German geopolitics. The high status of German academia provided an initial audience of Dutch academic geographers.
Mobile policies and shifting contexts: city‐regional competitiveness strategies in Amsterdam and Dublin
Authors: Bontje Marco , Lawton Philip
Published: May 2013

In the past decade international competitiveness has become the top priority of national, regional and urban governments in the advanced capitalist economy. Attracting and retaining creative and high‐educated talent as well as creative and knowledge‐intensive firms are considered essential ingredients of urban and city‐regional ‘recipes for success’. Amsterdam and Dublin have, at both city‐ and city‐regional level, been very active in preparing and implementing competitiveness strategies in which fostering and stimulating creativity, knowledge and innovation play a leading role. The crisis since 2008 has made a reconsideration of these strategies necessary. Is ‘creative knowledge’ still the preferred road ahead, and if it is, can existing competitiveness strategies be continued or should new strategies be developed?
Ranking the effectiveness of autologous blood conservation measures through validated modeling of independent clinical data
Authors: Singbartl Günter , Held Anna‐Lena , Singbartl Kai
Published: May 2013

Background

Future supply with allogeneic blood transfusions faces several crucial challenges that warrant thorough (re‐)evaluation of existing alternatives. Meta‐analyses have indicated a significant potential for autologous blood conservation (ABC) measures to reduce the need for allogeneic blood transfusions. The quality of currently available studies, however, prohibits definite conclusions. Under these circumstances, mathematical modeling offers unique opportunities to compare various ABC measures and to test the impact of different variables on efficacy and effectiveness.

Study Design and Methods

We performed an extensive search for clinical ABC studies, focusing on acute normovolemic hemodilution (ANH), intraoperative blood salvage (IBS), or preoperative autologous deposit (PAD). Only ABC studies providing a minimum set of clinical variables were included. Using a clinically validated mathematical model, we then calculated maximal allowable blood loss (efficacy) and increase in red blood cell (RBC) mass (effectiveness) to rank the three techniques.

Results

We identified 21 clinical ABC studies, including 3926 patients, as suitable for our model. Our model shows that IBS with high recovery rates is the most efficacious and effective ABC measure. PAD will reveal nearly similar efficacy and effectiveness, only if sufficient time for RBC regeneration has passed and if 4 PAD units or more are available. Our model further demonstrates that ANH as well as IBS with low recovery rates are the least efficacious and effective alternatives.

Conclusions

IBS appears to be the most efficacious and effective ABC measure. PAD can only reduce the need for allogeneic blood transfusions under certain circumstances. ANH does not appear to play an important role in ABC.
Low Cycle Fatigue of Alloy 617 at 850 °C and 950 °C
Authors: Wright J. K. , Carroll L. J. , Simpson J. A. , Wright R. N.
Published: May 2013

The low cycle fatigue behavior of Alloy 617 has been evaluated at 850 °C and 950 °C, the temperature range of particular interest for the intermediate heat exchanger on a proposed high-temperature gas-cooled nuclear reactor. Cycles to failure were measured as a function of total strain range and varying strain rate. Results of the current experiments compare well with previous work reported in the literature for a similar range of temperatures and strain rate. The combined data demonstrate a Coffin–Manson relationship, although the slope of the Coffin–Manson fit is close to −1 rather than the typically reported value of −0.5. At 850 °C and a strain rate of 10−3 /s Alloy 617 deforms by a plastic flow mechanism in low cycle fatigue and exhibits some cyclic hardening. At 950 °C for strain rates of 10−3–10−5 /s, Alloy 617 deforms by a solute drag creep mechanism during low cycle fatigue and does not show significant cyclic hardening or softening. At this temperature the strain rate has little influence on the cycles to failure for the strain ranges tested.
Four-Point Contact Ball Bearing Model With Deformable Rings
Authors: Lacroix Samy , Nélias Daniel , Leblanc Alexandre
Published: May 2013

In many applications, such as four-point contact slewing bearings or main shaft angular contact ball bearings, the rings and housings are so thin that the assumption of rigid rings does not hold anymore. In this paper, several methods are proposed to account for the flexibility of rings in a quasi-static ball bearing numerical model. The modeling approach consists of coupling a semianalytical approach and a finite element (FE) model to describe the deformation of the rings and housings. The manner in which this weak coupling is made differs depending on how the structural deformation of the ring and housing assemblies is injected into the set of nonlinear geometrical and equilibrium equations in order to solve them. These methods enable us to account for ring ovalization, ring twist, and raceway opening (including change of conformity) since a tulip deformation mode of the ring groove is observed for high contact angles. Either the torus fitting technique or mean displacement computation are used to determine these geometrical parameters. A comparison between the different approaches allows us to study, in particular, the impact of raceway conformity change. The loads used in this investigation are chosen in order that the maximum contact pressure (the Hertz pressure) at the ball-raceway interface remains below 2000 MPa, without any contact ellipse truncation. For the ball bearing example considered here, relative differences of up to 30% on the axial displacement, 10% on the maximum contact pressure, and 10% on the contact angle are observed by comparing rigid and deformable rings for a typical loading representative of the one encountered in operation. Despite the local change of conformity, which becomes significant at high contact angles and for thin ball bearing flanges, it is shown that this hardly affects the internal load distribution. The paper ends with a discussion on how the ring and housing flexibility may affect the loading envelope when the truncation of the contact ellipse is an issue.
A Comparison of Constitutive Equations for the Energy-Based Lifing Method
Authors: Wertz John , Holycross Casey , Herman Shen M.-H. , Scott-Emuakpor Onome , George Tommy , Cross Charles
Published: May 2013

Alternatives to quasi-static and dynamic constitutive relationships have been investigated with respect to a previously developed energy-based fatigue lifing method for various load profiles, which states: the total strain energy dissipated during both a quasi-static process and a dynamic process are equivalent and a fundamental material property. Specifically, constitutive relationships developed by Ramberg–Osgood and Halford were modified for application to the existing energy-based framework and were compared to the lifing method originally developed by Stowell. Extensive experimentation performed on Titanium 6Al-4V (Ti-64) combined with experimental data generated for Aluminum (Al) 6061-T6 at various temperatures were utilized in support of this investigation. This effort resulted in considerable improvements to the accuracy of the lifing prediction for materials with an endurance limit through application of a modified-Halford approach. Additionally, the relative equality in predictive accuracy between the modified-Stowell approach the modified-Ramberg–Osgood approach was demonstrated.
Nanostructured materials for supercapacitors
Authors: Meyyappan M.
Published: May 2013

Supercapacitor is an energy storage device that attempts to combine the high power density of a capacitor with the high energy density of a battery. Conventional supercapacitors use carbon based electrodes, mostly graphite. In recent years, alternatives such as carbon nanotubes, graphene, and other nanostructured materials have been considered to construct supercapacitor electrodes. This article reviews the progress in this area in addition to presenting a brief background on supercapacitors as energy storage medium and nanomaterials.
Distance dependence of tunneling thermovoltage on metal surfaces
Authors: Maksymovych Petro
Published: May 2013

Thermovoltage in a tunnel junction of a scanning tunneling microscope is a valuable observable that is known to have chemical sensitivity. Tunneling thermovoltage is typically measured at a fixed tip–surface distance. Here the author presents distance-dependent thermovoltage measurements that were systematically acquired over Ag(111) surface with a small coverage of adsorbates. The author confirms that the distance dependence can be used to obtain thermovoltage contrast due to the difference in the tunneling barrier height, and reveals that adjusting the width of the tunneling gap can significantly enhance thermoelectronic contrast. Furthermore, comparing tunneling thermovoltage and a synchronously acquired tunneling current as a function of gap width provided a direct verification of the Stovneng–Lipavsky model, which is often used to interpret tunneling thermovoltage experiments. Finally, the author shows that the distance-dependent thermovoltage can potentially be used to evaluate a thermal gradient in an atomic-scale tip–surface junction without explicit temperature calibration, which has so far not been achievable experimentally.
Analyzing pattern retention for multilayer focused ion beam induced quantum dot structures
Authors: Luengo-Kovac Marta , Saucer Timothy W. , Martin Andrew J. , Millunchick Joanna , Sih Vanessa
Published: May 2013

Atomic force microscopy was used to investigate the effects of templating parameters on focused ion beam patterned single-, two-, and three-layer InAs/GaAs(001) quantum dot structures. The number of layers, focused ion beam dwell time, and pattern spacing affected the fidelity of the quantum dots. The highest single dot fidelities were found in regions with 1 and 3 ms dwell times and 1 and 2 μm pattern spacings. A two-layer region patterned with 1 ms dwell time and 1 μm spacing was found to have 100% single quantum dot fidelity with no off-site dot nucleation in a 20 × 20 μm2 scan. Holes that were milled with 6 and 9 ms dwell times and 0.25 μm spacing became faceted, that is, deep, tightly packed, and rhombic, by the third layer. Autocorrelation of the images was used to analyze the periodicity and size of the features.
On the use of a single‐fiber multipoint plastic scintillation detector for 192Ir high‐dose‐rate brachytherapy
Authors: Therriault‐Proulx François , Beddar Sam , Beaulieu Luc
Published: May 2013

Purpose:

The goal of this study was to prove the feasibility of using a single‐fiber multipoint plastic scintillation detector (mPSD) as anin vivo verification tool during 192Ir high‐dose‐rate brachytherapy treatments.

Methods:

A three‐point detector was built and inserted inside a catheter‐positioning template placed in a water phantom. A hyperspectral approach was implemented to discriminate the different optical signals composing the light output at the exit of the single collection optical fiber. The mPSD was tested with different source‐to‐detector positions, ranging from 1 to 5 cm radially and over 10.5 cm along the longitudinal axis of the detector, and with various integration times. Several strategies for improving the accuracy of the detector were investigated. The device's accuracy in detecting source position was also tested.

Results:

Good agreement with the expected doses was obtained for all of the scintillating elements, with average relative differences from the expected values of 3.4 ± 2.1%, 3.0 ± 0.7%, and 4.5 ± 1.0% for scintillating elements from the distal to the proximal. A dose threshold of 3 cGy improved the general accuracy of the detector. An integration time of 3 s offered a good trade‐off between precision and temporal resolution. Finally, the mPSD measured the radioactive source positioning uncertainty to be no more than 0.32 ± 0.06 mm. The accuracy and precision of the detector were improved by a dose‐weighted function combining the three measurement points and known details about the geometry of the detector construction.

Conclusions:

The use of a mPSD for high‐dose‐rate brachytherapy dosimetry is feasible. This detector shows great promise for development ofin vivo applications for real‐time verification of treatment delivery.
Morals and Markets
Authors: Falk Armin , Szech Nora
Published: May 2013

Of Mice and Markets

Some goods, such as widgets, are freely bought and sold in markets without protest, whereas others, such as indulgences, are not. Some mice that have been bred for use in laboratory experiments turn out to be surplus to requirements and are subsequently sacrificed.
Falk and Szech
(p.
707
) studied the effect that marketplace negotiation has had on experimental subjects' willingness to pay for the upkeep of these surplus mice. Individuals were willing to pay much more to save the mice, but market-like exchanges lowered these prices.
Response to Comment on “Evidence of Abundant Purifying Selection in Humans for Recently Acquired Regulatory Functions”
Authors: Ward Lucas D. , Kellis Manolis
Published: May 2013

Green and Ewing propose corrections to our methodology, which we incorporate and extend here. The improved methodology supports our initial conclusion of extensive lineage-specific constraint concentrated in ENCODE elements. We clarify that our estimate is dependent on the constrained and neutral references used, which can further increase the number of nucleotides involved, because a particularly stringent definition was initially used.
Lorentz Meets Fano in Spectral Line Shapes: A Universal Phase and Its Laser Control
Authors: Ott Christian , Kaldun Andreas , Raith Philipp , Meyer Kristina , Laux Martin , Evers Jörg , Keitel Christoph H. , Greene Chris H. , Pfeifer Thomas
Published: May 2013

A Phase for Fano

In spectroscopy, samples placed between a steady light source and a detector are characterized based on the relative intensities of light absorbed at different frequencies. Temporal behavior—the relaxation of a photoexcited state—can be indirectly inferred from the absorption band shapes. The advent of ultrafast laser technology has enabled increasingly sophisticated measurements directly in the time domain.

Ott
et al.

(p.
716
; see the Perspective by

Lin and Chu

) present an analytical framework to account for asymmetric band shapes, termed Fano profiles, on the basis of a phase shift in the temporal dipole response.
Wolbachia
Invades
Anopheles stephensi
Populations and Induces Refractoriness to
Plasmodium
Infection
Authors: Bian Guowu , Joshi Deepak , Dong Yuemei , Lu Peng , Zhou Guoli , Pan Xiaoling , Xu Yao , Dimopoulos George , Xi Zhiyong
Published: May 2013

Infections Against Infection

In the same way that infection with the bacteria
Wolbachia
spp. can make
Aedes
mosquitoes resistant to dengue virus, there have been hints that these bacteria can interfere with the reproduction of malaria parasites.

Bian
et al.

(p.
748
) established a heritable
Wolbachia
infection in anopheline mosquitoes, which simultaneously suppressed the reproduction of malaria parasites within the adult female mosquitoes. The results hold promise for developing the model into a biocontrol agent to assist malaria control.
Proposed Change in Awarding Grants at NSF Spurs Partisan Sniping
Authors: Mervis Jeffrey
Published: May 2013

Debate continues over a bill that might allow Congress to intrude on the peer-review process
Pesticides Under Fire for Risks to Pollinators
Authors: Stokstad Erik
Published: May 2013

As the European Union moves to ban a popular type of pesticide, researchers struggle to assess exactly how dangerous the chemicals are to honey bees and other pollinators.
Cytolytic Activity of the Human Papillomavirus Type 16 E711-20Epitope-Specific Cytotoxic T Lymphocyte Is Enhanced by Heat Shock Protein 110 inHLA-A*0201Transgenic Mice
Authors: Ding Zhenzhen , Ou Rongying , Ni Bing , Tang Jun , Xu Yunsheng
Published: May 2013

Heat shock proteins (HSPs) have been successfully applied to a broad range of vaccines as biological adjuvants to enhance the immune response. The recently defined HSP110, in particular, exhibits strong protein binding affinity and is capable of enhancing the immunogenicity of protein antigens remarkably more than other HSP family members. In our previous study, we verified that murine HSP110 (mHSP110) significantly enhanced the immune response of a C57BL/6 mouse model to the H-2d-restricted human papillomavirus (HPV) E749-57epitope (short peptide spanning the 49th to 57th amino acid residues in the E7 protein). To determine whether HSP110 similarly enhances the immunogenicity of human epitope peptides, we used theHLA-A2transgenic mouse model to investigate the efficacy of the mHSP110 chaperone molecule as an immunoadjuvant of the human HLA-A2-restricted HPV16 E711-20epitope vaccine. Results showed that mHSP110 efficiently formed a noncovalently bound complex with the E711-20epitope. The mHSP110-E711-20complex induced epitope-specific splenocyte proliferation and E711-20-specific gamma interferon (IFN-γ) secretion. Importantly, cytotoxic T lymphocytes primed by the mHSP110-E711-20complex exerted strong cytolytic effects on target T2cells pulsed with the E711-20peptide or TC-1 cells transfected with theHLA-A2gene. In addition, the mHSP110-E711-20complex elicited strongerex vivoandin vivoantitumor responses than either emulsified complete Freund's adjuvant or HSP70-chaperoned E711-20peptide. These collective data suggest that HSP110 is a promising immunomodulator candidate for peptide-based human cancer vaccines, such as for the HLA-A2-restricted E711-20epitope.
Fluoroquinolone and Macrolide Resistance-Associated Mutations in Mycoplasma genitalium
Authors: Tagg Kaitlin A. , Jeoffreys Neisha J. , Couldwell Deborah L. , Donald Jennifer A. , Gilbert Gwendolyn L.
Published: May 2013

Mycoplasma genitalium
is a significant sexually transmitted pathogen, causing up to 25% of cases of nongonococcal urethritis in men, and it is strongly associated with cervicitis and pelvic inflammatory disease in women. Currently, the usual first-line treatment is the macrolide antibiotic azithromycin, but an increasing incidence of treatment failure over the last 5 years suggests the emergence of antibiotic resistance. The mutations responsible for macrolide resistance have been found in the 23S rRNA gene in numerous
M. genitalium
populations. A second-line antibiotic, the fluoroquinolone moxifloxacin, was thought to be a reliable alternative when azithromycin began to fail, but recent studies have identified mutations that may confer fluoroquinolone resistance in the genes
parC
and
gyrA
. The aim of this study was to determine the prevalence of antibiotic resistance in
M. genitalium
in Sydney, Australia, by detecting relevant mutations in the 23S rRNA gene,
parC
, and
gyrA. M. genitalium
-positive DNA extracts of specimens, collected from patients attending sexual health clinics in Sydney, were tested by PCR amplification and DNA sequence alignment. The 186 specimens tested included 143 initial patient specimens and 43 second, or subsequent, specimens from 24 patients. We identified known macrolide resistance-associated mutations in the 23S rRNA gene in 43% of the initial patient samples and mutations potentially associated with fluoroquinolone resistance in
parC
or
gyrA
sequences in 15% of the initial patient samples. These findings support anecdotal clinical reports of azithromycin and moxifloxacin treatment failures in Sydney. Our results indicate that further surveillance is needed, and testing and treatment protocols for
M. genitalium
infections may need to be reviewed.
Rapid and Reliable Identification of Staphylococcus aureus Capsular Serotypes by Means of Artificial Neural Network-Assisted Fourier Transform Infrared Spectroscopy
Authors: Grunert Tom , Wenning Mareike , Barbagelata María Sol , Fricker Martina , Sordelli Daniel O. , Buzzola Fernanda R. , Ehling-Schulz Monika
Published: May 2013

Staphylococcus aureus
capsular polysaccharides (CP) are important virulence factors and represent putative targets for vaccine development. Therefore, the purpose of this study was to develop a high-throughput method to identify and discriminate the clinically important
S. aureus
capsular serotypes 5, 8, and NT (nontypeable). A comprehensive set of clinical isolates derived from different origins and control strains, representative for each serotype, were used to establish a CP typing system based on Fourier transform infrared (FTIR) spectroscopy and chemometric techniques. By combining FTIR spectroscopy with artificial neuronal network (ANN) analysis, a system was successfully established, allowing a rapid identification and discrimination of all three serotypes. The overall accuracy of the ANN-assisted FTIR spectroscopy CP typing system was 96.7% for the internal validation and 98.2% for the external validation. One isolate in the internal validation and one isolate in the external validation failed in the classification procedure, but none of the isolates was incorrectly classified. The present study demonstrates that ANN-assisted FTIR spectroscopy allows a rapid and reliable discrimination of
S. aureus
capsular serotypes. It is suitable for diagnostic as well as large-scale epidemiologic surveillance of
S. aureus
capsule expression and provides useful information with respect to chronicity of infection.
Multicenter Evaluation of the Vitek MS Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry System for Identification of Gram-Positive Aerobic Bacteria
Authors: Rychert Jenna , Burnham Carey-Ann D. , Bythrow Maureen , Garner Omai B. , Ginocchio Christine C. , Jennemann Rebecca , Lewinski Michael A. , Manji Ryhana , Mochon A. Brian , Procop Gary W. , Richter Sandra S. , Sercia Linda , Westblade Lars F. , Ferraro Mary Jane , Branda John A.
Published: May 2013

Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF) is gaining momentum as a tool for bacterial identification in the clinical microbiology laboratory. Compared with conventional methods, this technology can more readily and conveniently identify a wide range of organisms. Here, we report the findings from a multicenter study to evaluate the Vitek MS v2.0 system (bioMérieux, Inc.) for the identification of aerobic Gram-positive bacteria. A total of 1,146 unique isolates, representing 13 genera and 42 species, were analyzed, and results were compared to those obtained by nucleic acid sequence-based identification as the reference method. For 1,063 of 1,146 isolates (92.8%), the Vitek MS provided a single identification that was accurate to the species level. For an additional 31 isolates (2.7%), multiple possible identifications were provided, all correct at the genus level. Mixed-genus or single-choice incorrect identifications were provided for 18 isolates (1.6%). Although no identification was obtained for 33 isolates (2.9%), there was no specific bacterial species for which the Vitek MS consistently failed to provide identification. In a subset of 463 isolates representing commonly encountered important pathogens, 95% were accurately identified to the species level and there were no misidentifications. Also, in all but one instance, the Vitek MS correctly differentiatedStreptococcus pneumoniaefrom other viridans group streptococci. The findings demonstrate that the Vitek MS system is highly accurate for the identification of Gram-positive aerobic bacteria in the clinical laboratory setting.
High Genetic Diversity of Newcastle Disease Virus in Poultry in West and Central Africa: Cocirculation of Genotype XIV and Newly Defined Genotypes XVII and XVIII
Authors: Snoeck Chantal J. , Owoade Ademola A. , Couacy-Hymann Emmanuel , Alkali Bello R. , Okwen Mbah P. , Adeyanju Adeniyi T. , Komoyo Giscard F. , Nakouné Emmanuel , Le Faou Alain , Muller Claude P.
Published: May 2013

Despite rampant Newcastle disease virus (NDV) outbreaks in Africa for decades, the information about the genetic characteristics of the virulent strains circulating in West and Central Africa is still scarce. In this study, 96 complete NDV fusion gene sequences were obtained from poultry sampled in Cameroon, Central African Republic, Côte d'Ivoire, and Nigeria between 2006 and 2011. Based on rational criteria recently proposed for the classification of NDV strains into classes, genotypes, and subgenotypes, we revisited the classification of virulent strains, in particular those from West and Central Africa, leading to their grouping into genotype XIV and newly defined genotypes XVII and XVIII, each with two subgenotypes. Phylogenetic analyses revealed that several (sub)genotypes are found in almost every country. In Cameroon, most strains were related to vaccine strains, but a single genotype XVII strain was also found. Only three highly similar genotype XVII strains were detected in Central African Republic. Subgenotypes XVIIa, XVIIIa, and XVIIIb cocirculated in Côte d'Ivoire, while subgenotypes XIVa, XIVb, XVIIa, XVIIb, and XVIIIb were found in Nigeria. While these genotypes are so far geographically restricted, local and international trade of domestic and exotic birds may lead to their spread beyond West and Central Africa. A high genetic diversity, mutations in important neutralizing epitopes paired with suboptimal vaccination, various levels of clinical responses of poultry and wild birds to virulent strains, strains with new cleavage sites, and other genetic modifications found in these genotypes tend to undermine and complicate NDV management in Africa.
A Carboxy-Terminally Truncated Human CPSF6 Lacking Residues Encoded by Exon 6 Inhibits HIV-1 cDNA Synthesis and Promotes Capsid Disassembly
Authors: Hori Takanori , Takeuchi Hiroaki , Saito Hideki , Sakuma Ryuta , Inagaki Yoshio , Yamaoka Shoji
Published: May 2013

Since HIV-1 replication is modulated at multiple stages by host cell factors, identification and characterization of those host cell factors are expected to contribute to the development of novel anti-HIV therapeutics. Previous studies showed that a C-terminally truncated cytosolic form of cleavage and polyadenylation-specific factor 6 (CPSF6-358) inhibits HIV-1 infection through interference with HIV-1 trafficking to the nucleus. Here we identified and characterized a different configuration of C-terminally truncated human CPSF6 (hCPSF6-375) through cDNA expression cloning coupled with ganciclovir-mediated lethal selection. Notably, hCPSF6-375, but not mouse CPSF6-358 (mCPSF6-358) as previously reported, remarkably interfered with viral cDNA synthesis after HIV-1 infection. Moreover, we found that hCPSF6-375 aberrantly accelerated the disassembly of the viral capsid in target cells, while CPSF6-358 did not. Sequence comparison of CPSF6-375 and CPSF6-358 cDNAs showed a lack of exon 6 and additional coding sequence for 54 amino acid residues in the C terminus of hCPSF6-375. Mutational analyses revealed that the residues encoded by exon 6, but not the C-terminal 54 residues in hCPSF6-375, is responsible for impaired viral cDNA synthesis by hCPSF6-375. This is the first report demonstrating a novel mode of HIV-1 inhibition by truncated forms of CPSF6 that involves rapid capsid disassembly and inhibition of viral cDNA synthesis. These findings could facilitate an increased understanding of viral cDNA synthesis in light of the viral capsid disassembly.
A Chemokine-Like Viral Protein Enhances Alpha Interferon Production by Plasmacytoid Dendritic Cells but Delays CD8+T Cell Activation and Impairs Viral Clearance
Authors: Wikstrom Matthew E. , Fleming Peter , Comerford Iain , McColl Shaun R. , Andoniou Christopher E. , Degli-Esposti Mariapia A.
Published: May 2013

Murine cytomegalovirus encodes numerous proteins that act on a variety of pathways to modulate the innate and adaptive immune responses. Here, we demonstrate that a chemokine-like protein encoded by murine cytomegalovirus activates the early innate immune response and delays adaptive immunity, thereby impairing viral clearance. The protein, m131/129 (also known as MCK-2), is not required to establish infection in the spleen; however, a mutant virus lacking m131/129 was cleared more rapidly from this organ. In the absence of m131/129 expression, there was enhanced activation of dendritic cells (DC), and virus-specific CD8+T cells were recruited into the immune response earlier. Viral mutants lacking m131/129 elicited weaker production of alpha interferon (IFN-α) at 40 h postinfection, indicating that this protein exerts its effects during early rounds of viral replication in the spleen. Furthermore, while wild-type and mutant viruses activated plasmacytoid dendritic cells (pDC) equally at this time, as measured by the upregulation of costimulatory molecules, the presence of m131/129 stimulated more pDC to secrete IFN-α, accounting for the stronger IFN-α response than from the wild-type virus. These data provide evidence for a novel immunomodulatory function of a viral chemokine and expose the multifunctionality of immune evasion proteins. In addition, these results broaden our understanding of the interplay between innate and adaptive immunity.
Specific Amino Acid Substitutions in the S Protein Prevent Its Excretion
In Vitro
and May Contribute to Occult Hepatitis B Virus Infection
Authors: Biswas Subhajit , Candotti Daniel , Allain Jean-Pierre
Published: May 2013

Occult hepatitis B virus (HBV) infection (OBI) is defined as low plasma level of HBV DNA with undetectable HBV surface antigen (HBsAg) outside the preseroconversion window period. The mechanisms leading to OBI remain largely unknown. The potential role of specific amino acid substitutions in the S protein from OBI in HBsAg production and excretion was examined
in vitro
. HBsAg was quantified in culture supernatants and cell extracts of HuH-7 cells transiently transfected with plasmids containing the S gene of eight HBsAg
+
controls and 18 OBI clones. The intracellular (IC)/extracellular (EC) HBsAg production ratio was ∼1.0 for the majority of controls. Three IC/EC HBsAg patterns were observed in OBI strains clones: pattern 1, an IC/EC ratio of 1.0, was found in 5/18 OBI clones, pattern 2, detectable IC but low or undetectable EC HBsAg (IC/EC, 7.0 to 800), was found in 6/18 OBIs, and pattern 3, low or undetectable IC and EC HBsAg, was found in 7/18 clones. Intracellular immunofluorescence staining showed that in pattern 2, HBsAg was concentrated around the nucleus, suggesting retention in the endoplasmic reticulum. The substitution M75T, Y100S, or P178R was present in 4/6 pattern 2 OBI clones. Site-directed-mutagenesis-corrected mutations reversed HBsAg excretion to pattern 1 and, when introduced into a control clone, induced pattern 2 except for Y100S. In a control and several OBIs, variants of a given quasispecies expressed HBsAg according to different patterns. However, the P178R substitution present in all cloned sequences of two OBI strains may contribute significantly to the OBI phenotype.
Accessory Genes Confer a High Replication Rate to Virulent Feline Immunodeficiency Virus
Authors: Troyer Ryan M. , Thompson Jesse , Elder John H. , VandeWoude Sue
Published: May 2013

Feline immunodeficiency virus (FIV) is a lentivirus that causes AIDS in domestic cats, similar to human immunodeficiency virus (HIV)/AIDS in humans. The FIV accessory protein Vif abrogates the inhibition of infection by cat APOBEC3 restriction factors. FIV also encodes a multifunctional OrfA accessory protein that has characteristics similar to HIV Tat, Vpu, Vpr, and Nef. To examine the role ofvifandorfAaccessory genes in FIV replication and pathogenicity, we generated chimeras between two FIV molecular clones with divergent disease potentials: a highly pathogenic isolate that replicates rapidlyin vitroand is associated with significant immunopathologyin vivo, FIV-C36 (referred to here as high-virulence FIV [HV-FIV]), and a less-pathogenic strain, FIV-PPR (referred to here as low-virulence FIV [LV-FIV]). Using PCR-driven overlap extension, we produced viruses in whichvif,orfA, or both genes from virulent HV-FIV replaced equivalent genes in LV-FIV. The generation of these chimeras is more straightforward in FIV than in primate lentiviruses, since FIV accessory gene open reading frames have very little overlap with other genes. All three chimeric viruses exhibited increased replication kineticsin vitrocompared to the replication kinetics of LV-FIV. Chimeras containing HV-Vif or Vif/OrfA had replication rates equivalent to those of the virulent HV-FIV parental virus. Furthermore, small interfering RNA knockdown of feline APOBEC3 genes resulted in equalization of replication rates between LV-FIV and LV-FIV encoding HV-FIV Vif. These findings demonstrate that Vif-APOBEC interactions play a key role in controlling the replication and pathogenicity of this immunodeficiency-inducing virus in its native host species and that accessory genes act as mediators of lentiviral strain-specific virulence.
Hepatitis C Virus Infection Upregulates CD55 Expression on the Hepatocyte Surface and Promotes Association with Virus Particles
Authors: Mazumdar Budhaditya , Kim Hangeun , Meyer Keith , Bose Sandip K. , Di Bisceglie Adrian M. , Ray Ratna B. , Diamond Michael S. , Atkinson John P. , Ray Ranjit
Published: May 2013

CD55 limits excessive complement activation on the host cell surface by accelerating the decay of C3 convertases. In this study, we observed that hepatitis C virus (HCV) infection of hepatocytes or HCV core protein expression in transfected hepatocytes upregulated CD55 expression at the mRNA and protein levels. Further analysis suggested that the HCV core protein or full-length (FL) genome enhanced CD55 promoter activity in a luciferase-based assay, which was further augmented in the presence of interleukin-6. Mutation of the CREB or SP-1 binding site on the CD55 promoter impaired HCV core protein-mediated upregulation of CD55. HCV-infected or core protein-transfected Huh7.5 cells displayed greater viability in the presence of CD81 and CD55 antibodies and complement. Biochemical analysis revealed that CD55 was associated with cell culture-grown HCV after purification by sucrose density gradient ultracentrifugation. Consistent with this, a polyclonal antibody to CD55 captured cell culture-grown HCV. Blocking antibodies against CD55 or virus envelope glycoproteins in the presence of normal human serum as a source of complement inhibited HCV infection. The inhibition was enhanced in the presence of both the antibodies and serum complement. Collectively, these results suggest that HCV induces and associates with a negative regulator of the complement pathway, a likely mechanism for immune evasion.
Crystal Structure of the Avian Astrovirus Capsid Spike
Authors: DuBois Rebecca M. , Freiden Pamela , Marvin Shauna , Reddivari Muralidhar , Heath Richard J. , White Stephen W. , Schultz-Cherry Stacey
Published: May 2013

Astroviruses are small, nonenveloped, single-stranded RNA viruses that cause diarrhea in a wide variety of mammals and birds. On the surface of the viral capsid are globular spikes that are thought to be involved in attachment to host cells. To understand the basis of species specificity, we investigated the structure of an avian astrovirus capsid spike and compared it to a previously reported human astrovirus capsid spike structure. Here we report the crystal structure of the turkey astrovirus 2 (TAstV-2) capsid surface spike domain, determined to 1.5-Å resolution, and identify three conserved patches on the surface of the spike that are candidate avian receptor-binding sites. Surprisingly, the overall TAstV-2 capsid spike structure is unique, with only distant structural similarities to the human astrovirus capsid spike and other viral capsid spikes. There is an absence of conserved putative receptor-binding sites between the human and avian spikes. However, there is evidence for carbohydrate-binding sites in both human and avian spikes, and studies with human astrovirus 1 (HAstV-1) suggest a minor role in infection for chondroitin sulfate but not heparin. Overall, our structural and functional studies provide new insights into astrovirus host cell entry, species specificity, and evolution.
Acute and chronic spectral domain optical coherence tomography features of branch retinal artery occlusion
Authors: Rodrigues Ian Aureliano Stephen
Published: May 2013

Branch retinal artery occlusion (BRAO) is a common vascular occlusive disorder. BRAO involving the posterior pole is usually symptomatic, but occasionally has very limited clinical features. We describe 2 cases where the underlying pathology was initially unclear and the diagnosis therefore not reached at presentation. Use of the latest retinal imaging, spectral domain optical coherence tomography (SD-OCT) enabled correct diagnosis of BRAO. The images demonstrate and contrast the fine changes that can be seen in the acute and chronic phases of this condition and illustrate how the pathogenesis of BRAO is confined to the outer retinal layers. We believe the subtle presentations of this common condition that we discuss highlight how diagnosis of BRAO can often be challenging, but may be facilitated by the use of SD-OCT retinal imaging.
Does contact with a podiatrist prevent the occurrence of a lower extremity amputation in people with diabetes? A systematic review and meta-analysis
Authors: Buckley C M , Perry I J , Bradley C P , Kearney P M
Published: May 2013

Objective

To determine the effect of contact with a podiatrist on the occurrence of Lower Extremity Amputation (LEA) in people with diabetes.

Design and data sources

We conducted a systematic review of available literature on the effect of contact with a podiatrist on the risk of LEA in people with diabetes. Eligible studies, published in English, were identified through searches of PubMed, CINAHL, EMBASE and Cochrane databases. The key terms, ‘podiatry’, ‘amputation’ and ‘diabetes’, were searched as Medical Subject Heading terms. Reference lists of selected papers were hand-searched for additional articles. No date restrictions were imposed.

Study selection

Published randomised and analytical observational studies of the effect of contact with a podiatrist on the risk of LEA in people with diabetes were included. Cross-sectional studies, review articles, chart reviews and case series were excluded. Two reviewers independently assessed titles, abstracts and full articles to identify eligible studies and extracted data related to the study design, characteristics of participants, interventions, outcomes, control for confounding factors and risk estimates.

Analysis

Meta-analysis was performed separately for randomised and non-randomised studies. Relative risks (RRs) with 95% CIs were estimated with fixed and random effects models as appropriate.

Results

Six studies met the inclusion criteria and five provided data included in meta-analysis. The identified studies were heterogenous in design and included people with diabetes at both low and high risk of amputation. Contact with a podiatrist did not significantly affect the RR of LEA in a meta-analysis of available data from randomised controlled trials (RCTs); (1.41, 95% CI 0.20 to 9.78, 2 RCTs) or from cohort studies; (0.73, 95% CI 0.39 to 1.33, 3 Cohort studies with four substudies in one cohort).

Conclusions

There are very limited data available on the effect of contact with a podiatrist on the risk of LEA in people with diabetes.
Patients’ subjective assessment of the duration of cataract surgery: a case series
Authors: Rothschild Pierre-Raphael , Grabar Sophie , Le Dû Brivael , Temstet Cyril , Rostaqui Olga , Brézin Antoine P
Published: May 2013

Objectives

Surgery duration is a source of preoperative anxiety for patients undergoing cataract surgery. To better inform patients, we evaluated the agreement between objective and patient-perceived surgery durations.

Design

Case series.

Setting

Public teaching university hospital (Paris, France).

Participants

During the study period, 368 cataract surgery cases performed on 285 patients were included, 85 cases were excluded from the final analysis. All patients who had uneventful phacoemulsification were included. Cases with any significant intraoperative adverse event or cases requiring additional anaesthesia other than topical were excluded. Resident performed cases were also excluded.

Primary and secondary outcomes

Procedures were timed (objective duration) and patients were asked, immediately afterwards, to assess the duration of their surgery (patient-assessed duration). The agreement between objective and patient-assessed durations as well as influencing factors was studied.

Results

Mean objective duration (13.9±5 min) and patient-assessed duration (15.3±6.9 min) were significantly correlated (Spearman's r=0.452, p<0.0001). Furthermore, Bland-Altman analysis and the intraclass correlation coefficient (0.341, 95% CI 0.23 to 0.44) were quite in agreement. On univariate analysis, senior-performed procedures were significantly shorter than those performed by juniors (13.4 vs 17.8 min, p=0.0001). Pain was recorded as ‘no sensation’ (31.5% of the cases), ‘mild sensation’ (41%), ‘moderate pain’ (23.3%), ‘intense pain’ (3.5%) and ‘unbearable pain’ (0.7%). Groups with high pain score had significantly longer procedures (p<0.001). Multivariate analysis revealed that the only independent factors associated with both the objective and patient-assessed durations of surgery were surgeon's experience and pain-score.

Conclusions

In our study, patients’ estimated and real duration of the surgery showed moderate agreement, suggesting that emotions associated with eye surgery under topical anaesthesia did not dramatically hinder the patients’ perception of time. However, the benefit of preoperative counselling regarding the duration of surgery will need further evaluation.
EQUIVALENCE OF THE PATH INTEGRAL FOR FERMIONS IN CARTESIAN AND SPHERICAL COORDINATES
Authors: BRIGGS ANDREW , CAMBLONG HORACIO E. , ORDÓÑEZ CARLOS R.
Published: May 2013

The path integral calculation for the free energy of a spin-1/2 Dirac-fermion gas is performed in spherical polar coordinates for a flat space–time geometry. Its equivalence with the Cartesian-coordinate representation is explicitly established. This evaluation involves a relevant limiting case of the fermionic path integral in a Schwarzschild background, whose near-horizon limit has been shown to be related to black hole thermodynamics.