bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of pincer-type femoroacetabular impingement
Authors: Sabetta Ettore , Scaravella Edoardo
Published: December 2015

Pincer femoroacetabular impingement (FAI) consists of pathological contact between the acetabular labrum and rim and the femoral head-neck junction. Manifold conditions underlie pincer FAI: anatomical abnormalities, malorientation of the acetabulum, torsional abnormalities of the neck and femoral shaft (these defects can be constitutional, post-traumatic or post-surgical), and involvement in sports characterized by repeated and sudden maximum joint excursions. In a high percentage of cases, pincer FAI is associated with cam FAI.

The aims of surgical treatment of pincer FAI are to eliminate the cause of the contact and repair the joint damage; the surgery may be open or arthroscopic, performed with an articular or extra-articular approach. Recently, arthroscopic treatment of FAI had a rapid and widespread diffusion due to the advantages it offers compared with the open technique. Arthroscopic treatment can repair the joint damage and in some cases, characterized by minor deformity, compensate for extra-articular defects. The acetabular labrum must always be preserved and sutured; only in extreme cases can it be sacrificed. Post-operative mobilization must respect the healing time of the labral repair.
Fijar cada reflejo Imagen fotográfica, retratos y experiencia subjetiva
Authors: Triquell Agustina
Published: December 2015

El presente artículo es el resultado del trabajo de investigación-intervención realizado en tres contextos específicos: el taller de mirada fotográfica de la Unidad Penitenciaria 48, del taller de Fotografía e identidad del bachillerato popular para jóvenes del sindicato de Empleados de Comercio y el Taller de Fotografía de la Biblioteca Popular de Anisacate (Sierras de Córdoba) para mujeres mayores. Si bien los contextos son diversos, nos centraremos en una problemática particular: las operaciones de construcción de la “imagen de sí” a partir de lo que denominaremos repertorios fotográficos autorreferenciales. La sistematización de los resultados se articulará a través de un recorrido por el lugar del retrato en la historia social de la fotografía, que nos permitirá dar cuenta de distintos modos de relación entre imagen y sujeto.
Tecnologías en la Educación Musical a Distancia en Contextos Universitarios Brasileños
Authors: Da Silveira Borne Leonardo
Published: December 2015

Este artículo se centra en las tecnologías usadas en las prácticas de educación musical en contextos de universidades en Brasil. Este documento es producto del recorte de una investigación de posgrado que se enfocó en las percepciones de ocho maestros de licenciatura en música sobre los recursos, sus elecciones, y los usos de los Objetos de Aprendizaje y de los Entornos Virtuales de Aprendizaje en cursos en línea. A través de un estudio cualitativo, que tuvo como base los pensamientos de Tardif y Lessard (2008) sobre el trabajo docente, pude verificar las maneras con las que los docentes caracterizan el OA, ya sea en sus dimensiones tecnológicas y de implementación o la educativa y pedagógica. Igualmente, sobre el EVA, pude examinar los puntos que toman como referencia cuando los participantes lo detallan, desde la articulación tecnológica o desde la interacción entre los actores. 
Corrosion Reliability Analysis Considering the Coupled Effect of Mechanical Stresses
Authors: Xie Chaoyang , Wang Pingfeng , Wang Zequn , Huang Hongzhong
Published: December 2015

Corrosion is one of the most critical failure mechanisms for engineering structures and systems, as corrosion damages grow with the increase of service time, thus diminish system reliability gradually. Despite tremendous efforts, effectively carrying out reliability analysis considering the complicated coupling effects for corrosion remains to be a grand challenge. There is a substantial need to develop sophisticated corrosion reliability models and effective reliability analysis approaches considering corrosion damage growth under coupled effects such as mechanical stresses. This paper presents a physics-of-failure model for pitting corrosion with the coupled effect of corrosion environment and mechanical stresses. With the developed model, corrosion damage growth can be projected and corrosion reliability can be analyzed. To carry out corrosion reliability analysis, the developed pitting corrosion model can be formulated as time-dependent limit state functions considering pit to crack transition, crack growth, and fracture failure mechanics. A newly developed maximum confidence enhancement (MCE)-based sequential sampling approach is then employed to improve the efficiency of corrosion reliability analysis with the time-dependent limit state functions. A case study is presented to illustrate the efficacy of the developed physics-of-failure model for corrosion considering the coupled mechanical stress effects, and the new corrosion reliability analysis methodology.
Analysis of Running and Technical Performance in Substitute Players in International Male Rugby Union Competition
Authors: Lacome Mathieu , Piscione Julien , Hager Jean-Philippe , Carling Christopher
Published: December 2015

Purpose:

To investigate the patterns and performance of substitutions in 18 international 15-a-side men’s rugby union matches.

Methods:

A semiautomatic computerized time–motion system compiled 750 performance observations for 375 players (422 forwards, 328 backs). Running and technical-performance measures included total distance run, high-intensity running (>18.0 km/h), number of individual ball possessions and passes, percentage of passes completed, and number of attempted and percentage of successful tackles.

Results:

A total of 184 substitutions (85.2%) were attributed to tactical and 32 (14.8%) to injury purposes respectively. The mean period for non-injury-purpose substitutions in backs (17.7%) occurred between 70 and 75 min, while forward substitutions peaked equally between 50–55 and 60–65 min (16.4%). Substitutes generally demonstrated improved running performance compared with both starter players who completed games and players whom they replaced (small differences, ES –0.2 to 0.5) in both forwards and backs over their entire time played. There was also a trend for better running performance in forward and back substitutes over their first 10 min of play compared with the final 10 min for replaced players (small to moderate differences, ES 0.3–0.6). Finally, running performance in both forward and back substitutes was generally lower (ES –0.1 to 0.3, unclear or small differences) over their entire 2nd-half time played compared with their first 10 min of play. The impact of substitutes on technical performance was generally considered unclear.

Conclusions:

This information provides practitioners with practical data relating to the physical and technical contributions of substitutions that subsequently could enable optimization of their impact on match play.
Older Women, Exercise to Music, and Yoga: Senses of Pleasure?
Authors: Humberstone Barbara , Stuart Sue
Published: December 2015

This paper examines the lived experience of older women participants in (a) a low-impact exercise to music (ETM) class and (b) a yoga class to uncover what is important for them in taking part in these classes. Researcher S is the instructor of the ETM group and draws upon individual and focus group interviews and participant observation. Researcher B is a member of the yoga class where she interviewed the women and undertook participant observations. Both authors are a similar age to the older women interviewees. Through a phenomenological interpretative approach, the paper examines the women’s perceptions of their exercise class and yoga experiences, highlighting pleasurable experiences and features that contribute to this enjoyment. The paper considers relationships between pleasure, wellbeing, the senses, physical activity, and aging, drawing upon a variety of analyses. It pays attention to the contextual features of the ETM and yoga classes in making available and accessible pleasurable physical activity experiences for the women and draws, in part, on ‘typologies’ of pleasure to frame the debate around older women, physical activity, and senses of pleasure. Our research highlights the considerable wellbeing affects for women when physical activity provision takes account of context (the spatial, cultural, social, and sentient).
Agreement of an Evaluation of the Forward-Step-Down Test by a Broad Cohort of Clinicians With That of an Expert Panel
Authors: Herman Gidon , Nakdimon Oren , Levinger Pazit , Springer Shmuel
Published: December 2015

Context:

The forward-step-down (FSD) test may be used to identify underlying pathologies related to lower-extremity injuries. However, research on its interrater reliability is limited.

Objective:

To assess the interrater reliability of the FSD test with a broad cohort of clinicians and to compare the level of agreement with an expert panel.

Design:

Single-measure, interrater reliability.

Setting:

Annual conference of the Israeli Physical Therapy Society.

Participants:

15 healthy subjects who performed the FSD test and 142 physical therapists (PTs) who evaluated performance.

Methods:

Each subject performed the FSD while being videoed. Six videos were selected by an expert panel for analysis. After viewing the videos, FSD performance was rated by 142 PTs, as well as by the expert panel, using a 3-level scale.

Main Outcome Measures:

Interrater reliability determined by intraclass correlation coefficient (ICC) and percentage of agreement with the expert panel.

Results:

Fair to good reliability and acceptable agreement were found for the entire sample of raters (ICC –.61, agreement 74%). The percentage of agreement was greater in the subgroup of raters who were familiar with the FSD than in those who were not (78.08% vs 69.32%, respectively, P = .004). Years of work experience did not affect the percentage of agreement (P = .141).

Conclusions:

Fair to good interrater reliably of the FSD test was demonstrated by a broad cohort of PTs. The findings support the clinical utility of the FSD test as an assessment tool for quality of movement.
Exploring the Relationship Between Athletic Identity and Beliefs About Rehabilitation Overadherence in College Athletes
Authors: Hilliard Robert C. , Blom Lindsey , Hankemeier Dorice , Bolin Jocelyn
Published: December 2015

Context:

Athletic identity has been associated with rehabilitation overadherence in college athletes.

Objectives:

To explore which constructs of athletic identity predict rehabilitation overadherence, gauge athletes’ views of the most salient aspect of their athletic participation, and understand their perceptions of the reasons they adhere to their rehabilitation program.

Design:

Cross-sectional, mixed methods.

Setting:

University athletic training clinics and online.

Participants:

Currently injured college athletes (N = 80; 51 male, 29 female).

Main Outcome Measures:

Athletic Identity Measurement Scale (AIMS), Rehabilitation Overadherence Questionnaire (ROAQ), and 2 open-ended questions about athletic participation and rehabilitation adherence.

Results:

Higher levels of athletic identity were associated with higher levels of rehabilitation overadherence (r = .29, P = .009). Hierarchical multiple regression used on AIMS subscales to predict ROAQ subscales did not reveal a significant model for the subscale “ignore practitioner recommendations.” However, a significant model was revealed for the subscale “attempt an expedited rehabilitation,” F5,73 = 2.56, P = .04, R2 = .15. Negative affectivity was the only significant contribution to the equation (β = 0.33, t = 2.64, P = .01). Content analysis revealed that bodily benefits, sport participation, personal achievement, social relationships, and athlete status were perceived to be the most important aspects of being an athlete. The themes of returning to competition, general health, and relationship beliefs were identified as the major factors for adhering to a rehabilitation program.

Conclusions:

Negative affectivity accounted for a significant but low amount of variance for rehabilitation overadherence, suggesting that athletic trainers should pay attention to personal variables such as athletic identity that might influence the rehabilitation process. Using the knowledge of why athletes adhere to their rehabilitation and what is most important to them about being an athlete, athletic trainers can use appropriate interventions to facilitate proper rehabilitation adherence.
Diagnostic Performance of Five Assays for Anti-Hepatitis E Virus IgG and IgM in a Large Cohort Study
Authors: Norder Heléne , Karlsson Marie , Mellgren Åsa , Konar Jan , Sandberg Elisabeth , Lasson Anders , Castedal Maria , Magnius Lars , Lagging Martin
Published: December 2015

Determination of anti-hepatitis E virus (anti-HEV) antibodies is still enigmatic. There is no gold standard, and results obtained with different assays often diverge. Herein, five assays were compared for detection of anti-HEV IgM and IgG. Serum samples from 500 Swedish blood donors and 316 patients, of whom 136 had suspected HEV infection, were analyzed. Concordant results for IgM and IgG with all assays were obtained only for 71% and 70% of patients with suspected hepatitis E, respectively. The range of sensitivity for anti-HEV detection was broad (42% to 96%); this was reflected in the detection limit, which varied up to 19-fold for IgM and 17-fold for IgG between assays. HEV RNA was analyzed in all patients and in those blood donors reactive for anti-HEV in any assay, and it was found in 26 individuals. Among all of the assays, both anti-HEV IgG and IgM were detected in 10 of those individuals. Twelve had only IgG and, in 7 of those 12, IgG was only detected with the two most sensitive assays. Three of the HEV-RNA-positive samples were negative for anti-HEV IgM and IgG in all assays. With the two most sensitive assays, anti-HEV IgG was identified in 16% of the blood donor samples and in 66% of patients with suspected HEV infection. Because several HEV-RNA-positive samples had only anti-HEV IgG without anti-HEV IgM or lacked anti-HEV antibodies, analysis for HEV RNA may be warranted as a complement in the laboratory diagnosis of ongoing HEV infection.
Detection of Rare Drug Resistance Mutations by Digital PCR in a Human Influenza A Virus Model System and Clinical Samples
Authors: Whale Alexandra S. , Bushell Claire A. , Grant Paul R. , Cowen Simon , Gutierrez-Aguirre Ion , O'Sullivan Denise M. , Žel Jana , Milavec Mojca , Foy Carole A. , Nastouli Eleni , Garson Jeremy A. , Huggett Jim F.
Published: December 2015

Digital PCR (dPCR) is being increasingly used for the quantification of sequence variations, including single nucleotide polymorphisms (SNPs), due to its high accuracy and precision in comparison with techniques such as quantitative PCR (qPCR) and melt curve analysis. To develop and evaluate dPCR for SNP detection using DNA, RNA, and clinical samples, an influenza virus model of resistance to oseltamivir (Tamiflu) was used. First, this study was able to recognize and reduce off-target amplification in dPCR quantification, thereby enabling technical sensitivities down to 0.1% SNP abundance at a range of template concentrations, a 50-fold improvement on the qPCR assay used routinely in the clinic. Second, a method was developed for determining the false-positive rate (background) signal. Finally, comparison of dPCR with qPCR results on clinical samples demonstrated the potential impact dPCR could have on clinical research and patient management by earlier (trace) detection of rare drug-resistant sequence variants. Ultimately this could reduce the quantity of ineffective drugs taken and facilitate early switching to alternative medication when available. In the short term such methods could advance our understanding of microbial dynamics and therapeutic responses in a range of infectious diseases such as HIV, viral hepatitis, and tuberculosis. Furthermore, the findings presented here are directly relevant to other diagnostic areas, such as the detection of rare SNPs in malignancy, monitoring of graft rejection, and fetal screening.
Diagnostic Accuracy of PCR Alone and Compared to Urinary Antigen Testing for Detection of Legionella spp.: a Systematic Review
Authors: Avni Tomer , Bieber Amir , Green Hefziba , Steinmetz Tali , Leibovici Leonard , Paul Mical
Published: December 2015

The diagnosis of Legionnaires' disease (LD) is based on the isolation of
Legionella
spp., a 4-fold rise in antibodies, a positive urinary antigen (UA), or direct immunofluorescence tests. PCR is not accepted as a diagnostic tool for LD. This systematic review assesses the diagnostic accuracy of PCR in various clinical samples with a direct comparison versus UA. We included prospective or retrospective cohort and case-control studies. Studies were included if they used the Centers for Disease Control and Prevention consensus definition criteria of LD or a similar one, assessed only patients with clinical pneumonia, and reported data for all true-positive, false-positive, true-negative, and false-negative results. Two reviewers abstracted data independently. Risk of bias was assessed using Quadas-2. Summary sensitivity and specificity values were estimated using a bivariate model and reported with a 95% confidence interval (CI). Thirty-eight studies were included. A total of 653 patients had confirmed LD, and 3,593 patients had pneumonia due to other pathogens. The methodological quality of the studies as assessed by the Quadas-2 tool was poor to fair. The summary sensitivity and specificity values for diagnosis of LD in respiratory samples were 97.4% (95% CI, 91.1% to 99.2%) and 98.6% (95% CI, 97.4% to 99.3%), respectively. These results were mainly unchanged by any covariates tested and subgroup analysis. The diagnostic performance of PCR in respiratory samples was much better than that of UA. Compared to UA, PCR in respiratory samples (especially in sputum samples or swabs) revealed a significant advantage in sensitivity and an additional diagnosis of 18% to 30% of LD cases. The diagnostic performance of PCR in respiratory samples was excellent and preferable to that of the UA. Results were independent on the covariate tested. PCR in respiratory samples should be regarded as a valid tool for the diagnosis of LD.
Visualization of Host-Polerovirus Interaction Topologies Using Protein Interaction Reporter Technology
Authors: DeBlasio Stacy L. , Chavez Juan D. , Alexander Mariko M. , Ramsey John , Eng Jimmy K. , Mahoney Jaclyn , Gray Stewart M. , Bruce James E. , Cilia Michelle
Published: December 2015

Demonstrating direct interactions between host and virus proteins during infection is a major goal and challenge for the field of virology. Most protein interactions are not binary or easily amenable to structural determination. Using infectious preparations of a polerovirus (
Potato leafroll virus
[PLRV]) and protein interaction reporter (PIR), a revolutionary technology that couples a mass spectrometric-cleavable chemical cross-linker with high-resolution mass spectrometry, we provide the first report of a host-pathogen protein interaction network that includes data-derived, topological features for every cross-linked site that was identified. We show that PLRV virions have hot spots of protein interaction and multifunctional surface topologies, revealing how these plant viruses maximize their use of binding interfaces. Modeling data, guided by cross-linking constraints, suggest asymmetric packing of the major capsid protein in the virion, which supports previous epitope mapping studies. Protein interaction topologies are conserved with other species in the
Luteoviridae
and with unrelated viruses in the
Herpesviridae
and
Adenoviridae
. Functional analysis of three PLRV-interacting host proteins
in planta
using a reverse-genetics approach revealed a complex, molecular tug-of-war between host and virus. Structural mimicry and diversifying selection—hallmarks of host-pathogen interactions—were identified within host and viral binding interfaces predicted by our models. These results illuminate the functional diversity of the PLRV-host protein interaction network and demonstrate the usefulness of PIR technology for precision mapping of functional host-pathogen protein interaction topologies.

IMPORTANCE
The exterior shape of a plant virus and its interacting host and insect vector proteins determine whether a virus will be transmitted by an insect or infect a specific host. Gaining this information is difficult and requires years of experimentation. We used protein interaction reporter (PIR) technology to illustrate how viruses exploit host proteins during plant infection. PIR technology enabled our team to precisely describe the sites of functional virus-virus, virus-host, and host-host protein interactions using a mass spectrometry analysis that takes just a few hours. Applications of PIR technology in host-pathogen interactions will enable researchers studying recalcitrant pathogens, such as animal pathogens where host proteins are incorporated directly into the infectious agents, to investigate how proteins interact during infection and transmission as well as develop new tools for interdiction and therapy.
Scanning Mutagenesis of Human Cytomegalovirus Glycoprotein gH/gL
Authors: Schultz Eric P. , Lanchy Jean-Marc , Ellerbeck Erin E. , Ryckman Brent J.
Published: December 2015

The core, conserved function of the herpesvirus gH/gL is to promote gB-mediated membrane fusion during entry, although the mechanism is poorly understood. The human cytomegalovirus (HCMV) gH/gL can exist as either the gH/gL/gO trimer or the gH/gL/UL128/UL130/UL131 (gH/gL/UL128-131) pentamer. One model suggests that gH/gL/gO provides the core fusion role during entry into all cells within the broad tropism of HCMV, whereas gH/gL/UL128-131 acts at an earlier stage, by a distinct receptor-binding mechanism to enhance infection of select cell types, such as epithelial cells, endothelial cells, and monocytes/macrophages. To further study the distinct functions of these complexes, mutants with individual charged cluster-to-alanine (CCTA) mutations of gH and gL were combined to generate a library of 80 mutant gH/gL heterodimers. The majority of the mutant gH/gL complexes were unable to facilitate gB-mediated membrane fusion in transient-expression cell-cell fusion experiments. In contrast, these mutants supported the formation of gH/gL/UL128-131 complexes that could block HCMV infection in receptor interference experiments. These results suggest that receptor interactions with gH/gL/UL128-131 involve surfaces contained on the UL128-131 proteins but not on gH/gL. gH/gL/UL128-131 receptor interference could be blocked with anti-gH antibodies, suggesting that interference is a cell surface phenomenon and that anti-gH antibodies can block gH/gL/UL128-131 in a manner that is distinct from that for gH/gL/gO.

IMPORTANCE
Interest in the gH/gL complexes of HCMV (especially gH/gL/UL128-131) as vaccine targets has far outpaced our understanding of the mechanism by which they facilitate entry and contribute to broad cellular tropism. For Epstein-Barr virus (EBV), gH/gL and gH/gL/gp42 are both capable of promoting gB fusion for entry into epithelial cells and B cells, respectively. In contrast, HCMV gH/gL/gO appears to be the sole fusion cofactor that promotes gB fusion activity, whereas gH/gL/UL128-131 expands cell tropism through a distinct yet unknown mechanism. This study suggests that the surfaces of HCMV gH/gL are critical for promoting gB fusion but are dispensable for gH/gL/UL128-131 receptor interaction. This underscores the importance of gH/gL/gO in HCMV entry into all cell types and reaffirms the complex as a candidate target for vaccine development. The two functionally distinct forms of gH/gL present in HCMV make for a useful model with which to study the fundamental mechanisms by which herpesvirus gH/gL regulates gB fusion.
Glycine at Position 622 in PB1 Contributes to the Virulence of H5N1 Avian Influenza Virus in Mice
Authors: Feng Xiaoxiao , Wang Zeng , Shi Jianzhong , Deng Guohua , Kong Huihui , Tao Shiyu , Li Changyao , Liu Liling , Guan Yuntao , Chen Hualan
Published: December 2015

We isolated two H5N1 viruses, A/duck/Hunan/S4020/2008 (DK/08) and A/chicken/Guangxi/S2039/2009 (CK/09), from live-bird markets during routine surveillance and found that these two viruses are genetically similar but differ in their replication and virulence in mice. The CK/09 virus is lethal for mice with a 50% mouse lethal dose (MLD
50
) of 1.6 log
10
50% egg infectious doses (EID
50
), whereas the DK/08 virus is nonpathogenic for mice with an MLD
50
value of 6.2 log
10
EID
50
. We explored the genetic basis of the virulence difference of these two viruses by generating a series of reassortant viruses and mutants in the lethal virus CK/09 background and evaluating their virulence in mice. We found that the PB1 gene of the DK/08 virus dramatically attenuated the virulence of the CK/09 virus and that the amino acid at position 622 in PB1 made an important contribution. We further demonstrated that the mutation of glycine (G) to aspartic acid (D) at position 622 in PB1 partially impaired the binding of PB1 to viral RNA, thereby dramatically decreasing the polymerase activity and attenuating H5N1 virus virulence in mice. Our results identify a novel virulence-related marker of H5N1 influenza viruses and provide a new target for live attenuated vaccine development.

IMPORTANCE
H5N1 avian influenza viruses have caused the deaths of nearly 60% of the humans that they have infected since 1997 and clearly represent a threat to public health. A thorough understanding of the genetic basis of virulence determinants will provide important insights for antiviral drug and live attenuated vaccine development. Several virulence-related markers in the PB2, PA, M1, and NS1 proteins of H5N1 viruses have been identified. In this study, we isolated two H5N1 avian influenza viruses that are genetically similar but differ in their virulence in mice, and we identified a new virulence-related marker in the PB1 gene. We found that the mutation of glycine (G) to aspartic acid (D) at position 622 in PB1 partially impairs the binding of PB1 to viral RNA, thereby attenuating H5N1 virus virulence in mice. This newly identified virulence-related marker could be applied to the development of live attenuated vaccines against H5N1 influenza.
Structural, Mechanistic, and Antigenic Characterization of the Human Astrovirus Capsid
Authors: York Royce L. , Yousefi Payam A. , Bogdanoff Walter , Haile Sara , Tripathi Sarvind , DuBois Rebecca M.
Published: December 2015

Human astroviruses (HAstVs) are nonenveloped, positive-sense, single-stranded RNA viruses that are a leading cause of viral gastroenteritis. HAstV particles display T=3 icosahedral symmetry formed by 180 copies of the capsid protein (CP), which undergoes proteolytic maturation to generate infectious HAstV particles. Little is known about the molecular features that govern HAstV particle assembly, maturation, infectivity, and immunogenicity. Here we report the crystal structures of the two main structural domains of the HAstV CP: the core domain at 2.60-Å resolution and the spike domain at 0.95-Å resolution. Fitting of these structures into the previously determined 25-Å-resolution electron cryomicroscopy density maps of HAstV allowed us to characterize the molecular features on the surfaces of immature and mature T=3 HAstV particles. The highly electropositive inner surface of HAstV supports a model in which interaction of the HAstV CP core with viral RNA is a driving force in T=3 HAstV particle formation. Additionally, mapping of conserved residues onto the HAstV CP core and spike domains in the context of the immature and mature HAstV particles revealed dramatic changes to the exposure of conserved residues during virus maturation. Indeed, we show that antibodies raised against mature HAstV have reactivity to both the HAstV CP core and spike domains, revealing for the first time that the CP core domain is antigenic. Together, these data provide new molecular insights into HAstV that have practical applications for the development of vaccines and antiviral therapies.

IMPORTANCE
Astroviruses are a leading cause of viral diarrhea in young children, immunocompromised individuals, and the elderly. Despite the prevalence of astroviruses, little is known at the molecular level about how the astrovirus particle assembles and is converted into an infectious, mature virus. In this paper, we describe the high-resolution structures of the two main astrovirus capsid proteins. Fitting these structures into previously determined low-resolution maps of astrovirus allowed us to characterize the molecular surfaces of immature and mature astroviruses. Our studies provide the first evidence that astroviruses undergo viral RNA-dependent assembly. We also provide new insight into the molecular mechanisms that lead to astrovirus maturation and infectivity. Finally, we show that both capsid proteins contribute to the adaptive immune response against astrovirus. Together, these studies will help to guide the development of vaccines and antiviral drugs targeting astrovirus.
The SD1 Subdomain of Venezuelan Equine Encephalitis Virus Capsid Protein Plays a Critical Role in Nucleocapsid and Particle Assembly
Authors: Reynaud Josephine M. , Lulla Valeria , Kim Dal Young , Frolova Elena I. , Frolov Ilya
Published: December 2015

Venezuelan equine encephalitis virus (VEEV) is an important human and animal pathogen, for which no safe and efficient vaccines or therapeutic means have been developed. Viral particle assembly and budding processes represent potential targets for therapeutic intervention. However, our understanding of the mechanistic process of VEEV assembly, RNA encapsidation, and the roles of different capsid-specific domains in these events remain to be described. The results of this new study demonstrate that the very amino-terminal VEEV capsid-specific subdomain SD1 is a critical player in the particle assembly process. It functions in a virus-specific mode, and its deletion, mutation, or replacement by the same subdomain derived from other alphaviruses has strong negative effects on infectious virus release. VEEV variants with mutated SD1 accumulate adaptive mutations in both SD1 and SD2, which result in a more efficiently replicating phenotype. Moreover, efficient nucleocapsid and particle assembly proceeds only when the two subdomains, SD1 and SD2, are derived from the same alphavirus. These two subdomains together appear to form the central core of VEEV nucleocapsids, and their interaction is one of the driving forces of virion assembly and budding. The similar domain structures of alphavirus capsid proteins suggest that this new knowledge can be applied to other alphaviruses.

IMPORTANCE
Alphaviruses are a group of human and animal pathogens which cause periodic outbreaks of highly debilitating diseases. Despite significant progress made in understanding the overall structure of alphavirus and VEEV virions, and glycoprotein spikes in particular, the mechanistic process of nucleocapsid assembly, RNA encapsidation, and the roles of different capsid-specific domains in these processes remain to be described. Our new data demonstrate that the very amino-terminal subdomain of Venezuelan equine encephalitis virus capsid protein, SD1, plays a critical role in the nucleocapsid assembly. It functions synergistically with the following SD2 (helix I) and appears to form a core in the center of nucleocapsid. The core formation is one of the driving forces of alphavirus particle assembly.
HMGB1 Promotes Hepatitis C Virus Replication by Interaction with Stem-Loop 4 in the Viral 5′ Untranslated Region
Authors: Yu Rong , Yang Darong , Lei Shaohua , Wang Xiaohong , Meng Xianghe , Xue Binbin , Zhu Haizhen
Published: December 2015

High-mobility group box 1 (HMGB1) protein is a highly conserved nuclear protein involved in multiple human diseases, including infectious diseases, immune disorders, metabolic disorders, and cancer. HMGB1 is comprised of two tandem HMG boxes (the A box and the B box) containing DNA-binding domains and an acidic C-terminal peptide. It has been reported that HMGB1 enhances viral replication by binding to viral proteins. However, its role in hepatitis C virus (HCV) replication is unknown. Here, we show that HMGB1 promoted HCV replication but had no effect on HCV translation. RNA immunoprecipitation experiments indicated that the positive strand, not the negative strand, of HCV RNA interacted with HMGB1. HCV infection triggered HMGB1 protein translocation from the nucleus to the cytoplasm, in which it interacted with the HCV genome. Moreover, the A box of HMGB1 is the pivotal domain to interact with stem-loop 4 (SL4) of the HCV 5′ untranslated region. Deletion of the HMGB1 A box abrogated the enhancement of HCV replication by HMGB1. Our data suggested that HMGB1 serves as a proviral factor of HCV to facilitate viral replication in hepatocytes by interaction with the HCV genome.

IMPORTANCEHepatitis C virus (HCV) is a major global health threat, affecting more than 170 million people infection worldwide. These patients are at high risk of developing severe liver diseases such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Currently, no vaccine is available. Many host factors may be implicated in the pathogenesis of HCV-related diseases. In this study, we found a novel HCV RNA-binding protein, HMGB1, that promotes HCV RNA replication. Moreover, SL4 in the 5′ untranslated region of the HCV genome is the key region for HMGB1 binding, and the A box of HMGB1 protein is the functional domain to interact with HCV RNA and enhance viral replication. HMGB1 appears to play an important role in HCV-related diseases, and further investigation is warranted to elucidate the specific actions of HMGB1 in HCV pathogenesis.
Abortively Infected Astrocytes Appear To Represent the Main Source of Interferon Beta in the Virus-Infected Brain
Authors: Pfefferkorn Cathleen , Kallfass Carsten , Lienenklaus Stefan , Spanier Julia , Kalinke Ulrich , Rieder Martina , Conzelmann Karl-Klaus , Michiels Thomas , Staeheli Peter
Published: December 2015

Interferon beta (IFN-β) is a key component of cellular innate immunity in mammals, and it constitutes the first line of defense during viral infection. Studies with cultured cells previously showed that almost all nucleated cells are able to produce IFN-β to various extents, but information about the
in vivo
sources of IFN-β remains incomplete. By applying immunohistochemistry and employing conditional-reporter mice that express firefly luciferase under the control of the IFN-β promoter in either all or only distinct cell types, we found that astrocytes are the main producers of IFN-β after infection of the brain with diverse neurotropic viruses, including rabies virus, Theiler's murine encephalomyelitis virus, and vesicular stomatitis virus. Analysis of a panel of knockout mouse strains revealed that sensing of viral components via both RIG-I-like helicases and Toll-like receptors contributes to IFN induction in the infected brain. A genetic approach to permanently mark rabies virus-infected cells in the brain showed that a substantial number of astrocytes became labeled and, therefore, must have been infected by the virus at least transiently. Thus, our results strongly indicate that abortive viral infection of astrocytes can trigger pattern recognition receptor signaling events which result in secretion of IFN-β that confers antiviral protection.

IMPORTANCE
Previous work indicated that astrocytes are the main producers of IFN after viral infection of the central nervous system (CNS), but it remained unclear how astrocytes might sense those viruses which preferentially replicate in neurons. We have now shown that virus sensing by both RIG-I-like helicases and Toll-like receptors is involved. Our results further demonstrate that astrocytes get infected in a nonproductive manner under these conditions, indicating that abortive infection of astrocytes plays a previously unappreciated role in the innate antiviral defenses of the CNS.
Chemothorax: a rare cause of a transudative pleural effusion
Authors: Kelly Devin , Geottman David , Sarodia Bipin
Published: December 2015

We discovered a rare cause of pleural effusion, chemothorax. In this case, a patient with invasive ductal breast carcinoma was admitted for a large and symptomatic pleural effusion. The radiology report obtained prior to admission did not describe the location of the Infuse-a-Port catheter. After a bedside thoracentesis demonstrated results consistent with chemotherapy infusate in the pleural space, further review of the medical imaging demonstrated that the catheter was in the pleural space.
In what direction should the fishing mortality target change when natural mortality increases within an assessment?
Authors: Legault Christopher M. , Palmer Michael C.
Published: December 2015

Traditionally, the natural mortality rate (M) in a stock assessment is assumed to be constant. When M increases within an assessment, the question arises how to change the fishing mortality rate target (FTarget). Per recruit considerations lead to an increase in FTarget, while limiting total mortality leads to a decrease in FTarget. Application of either approach can result in nonsensical results. Short-term gains in yield associated with high FTarget values should be considered in light of potential losses in future yield if the high total mortality rate leads to a decrease in recruitment. Examples using yellowtail flounder (Limanda ferruginea) and Atlantic cod (Gadus morhua) are used to demonstrate that FTarget can change when M increases within an assessment and to illustrate the consequences of different FTarget values. When a change in M within an assessment is contemplated, first consider the amount and strength of empirical evidence to support the change. When the empirical evidence is not strong, we recommend using a constant M. If strong empirical evidence exists, we recommend estimating FTarget for a range of stock–recruitment relationships and evaluating the trade-offs between risk of overfishing and forgone yield.
The maternal effect of differences in egg size influence metabolic rate and hypoxia induced hatching in Atlantic salmon eggs: implications for respiratory gas exchange across the egg capsule
Authors: Polymeropoulos Elias. T. , Elliott Nicholas G. , Frappell Peter B.
Published: December 2015

The maternal effect of fish egg size has profound implications for oxygen transfer across the egg shell surface, and therefore metabolism, especially under adverse environmental conditions like hypoxia. We found that metabolic rate ([Formula: see text]) of Atlantic salmon alevins was higher than of eggs in normoxia and hypoxia. Equally, the [Formula: see text] of smaller eggs from maiden spawners was lower than that of larger eggs from repeat spawners. Critical partial pressure of oxygen (PO2) for hatching was lower in eggs from repeat spawners. Generally, the PO2within the egg capsule was lower for a given ambient PO2and decreased further with hypoxia, and the internal PO2was higher, the bigger the volume of the egg. Therefore, we conclude that the egg capsule poses a major barrier to oxygen exchange for the mature embryo that is more severe in eggs from maiden spawners than in eggs from repeat spawners. This was corroborated by a more advantageous egg surface area to [Formula: see text] ratio in eggs from repeat spawners. These findings challenge the “bigger is worse during incubation” hypothesis.
Groups whose proper subgroups of infinite rank have minimax conjugacy classes
Authors: Bouchelaghem Mounia , Trabelsi Nadir
Published: December 2015

If [Formula: see text] is a class of groups, then a group [Formula: see text] is said to be a [Formula: see text]-group, if [Formula: see text] is a [Formula: see text]-group for all [Formula: see text]. This is a generalization of the familiar property of being an [Formula: see text]-group. In the present paper we consider a class [Formula: see text] of soluble-by-finite minimax groups such that [Formula: see text] is a subgroup closed class and if [Formula: see text] is a non-[Formula: see text]-group whose proper subgroups of infinite rank are [Formula: see text]-groups, then there exists a prime [Formula: see text] such that every finite homomorphic image of [Formula: see text] is a cyclic [Formula: see text]-group. Our main result states that if [Formula: see text] is a locally (soluble-by-finite) group of infinite rank which has no simple factor group of infinite rank and if all proper subgroups of [Formula: see text] of infinite rank are [Formula: see text]-groups, then so are all proper subgroups of [Formula: see text]. One can take for [Formula: see text] the class of finite, polycyclic-by-finite, Chernikov, reduced minimax or soluble-by-finite minimax groups.
Laser-Induced Magnetization Dynamics of GdFeCo Film Probing by Time Resolved Magneto-Optic Kerr Effect
Authors: He Wei , Wu Hong-Ye , Cai Jian-Wang , Liu Yao-Wen , Cheng Zhao-Hua
Published: December 2015

Laser-induced magnetization dynamics in Gd[Formula: see text]Fe[Formula: see text]Co[Formula: see text] (GdFeCo) film was investigated by time-resolved magneto-optical effect. After an ultrafast demagnetization and a magnetization recovery process, a second slower drop from several picoseconds (ps) to 200[Formula: see text]ps was observed. Previous report explained it as the demagnetization of Gd sublattice. However, when timescale extended up to 5 nanosecond (ns), we identified it as the part of an oscillated magnetization precession. It presents the change of magnetization orientation rather than the change of magnetization amplitude. Our results reveal that the low thermal diffusion coefficient of GdFeCo film plays an important role in the laser-induced magnetization dynamics of GdFeCo film.
Palaeomagnetism and geochronology of mid-Neoproterozoic Yanbian dykes, South China: implications for a
c.
820–800 Ma true polar wander event and the reconstruction of Rodinia
Authors: Niu Jiawen , Li Zheng-Xiang , Zhu Weiguang
Published: December 2015

We present new palaeomagnetic data from two generations of mafic dykes in the Yanbian region of the western South China Block, dated by the zircon U–Pb method at 824±6 and 806±8 Ma, respectively. The primary origin for the characteristic remanent magnetizations is supported by a positive baked contact test, a dyke-tilt test and rock magnetic data. After tilt corrections, 10 dykes from the
c.
824 Ma group gave a mean remanent direction of
D
=230.1°,
I
=−72.6° with
k
=16.3 and α
95
=12.3°, corresponding to a palaeopole at 42.5 °N, 131.8 °E with
A
95
=19.0°. Three dykes from the
c.
806 Ma group give a mean direction of
D
=284.5°,
I
=42.6° with
k
=76.5 and α
95
=14.2, corresponding to a virtual geomagnetic pole (VGP) at 18.2 °N, 31.0 °E with
A
95
=20.4°. After correcting for a 5° vertical-axis rotation of the study region, the two pole positions are at 45.1 °N, 130.4 °E and 14.1 °N, 32.5 °E, respectively. The
c.
825–720 Ma palaeopole position from South China, East Svalbard and neighbouring continents fall on great circles on two alternative Rodinia reconstructions, possibly reflecting oscillating inertial interchange true polar wander events (IITPWs).
Inapproximability for Antiferromagnetic Spin Systems in the Tree Nonuniqueness Region
Authors: Galanis Andreas , Štefankovič Daniel , Vigoda Eric
Published: December 2015

A remarkable connection has been established for antiferromagnetic 2-spin systems, including the Ising and hard-core models, showing that the computational complexity of approximating the partition function for graphs with maximum degree Δ undergoes a phase transition that coincides with the statistical physics uniqueness/nonuniqueness phase transition on the infinite Δ-regular tree. Despite this clear picture for 2-spin systems, there is little known for multispin systems. We present the first analog of this in approximability results for multispin systems.

The main difficulty in previous inapproximability results was analyzing the behavior of the model on random Δ-regular bipartite graphs, which served as the gadget in the reduction. To this end, one needs to understand the moments of the partition function. Our key contribution is connecting: (i) induced matrix norms, (ii) maxima of the expectation of the partition function, and (iii) attractive fixed points of the associated tree recursions (belief propagation). The view through matrix norms allows a simple and generic analysis of the second moment for any spin system on random Δ-regular bipartite graphs. This yields concentration results for any spin system in which one can analyze the maxima of the first moment. The connection to fixed points of the tree recursions enables an analysis of the maxima of the first moment for specific models of interest.

For
k
-colorings we prove that for even
k
, in a tree nonuniqueness region (which corresponds to
k
< Δ) there is no FPRAS, unless NP = RP, to approximate the number of colorings for triangle-free Δ-regular graphs. Our proof extends to the antiferromagnetic Potts model, and, in fact, to every antiferromagnetic model under a mild condition.
The Importance of Cross-layer Considerations in a Standardized WSN Protocol Stack Aiming for IoT
Authors: Pavkovic Bogdan , Batic Marko , Tomasevic Nikola
Published: December 2015

The Internet of Things (IoT) envisages expanding the current Internet with a huge number of intelligent communicating devices. Wireless sensor networks (WSNs) integrating IoT will rely on a set of the open standards striving to offer scalability and reliability in a variety of operating scenarios and conditions. Standardized protocols will tackle some of the major WSN challenges like energy efficiency, intrinsic impairments of low-power wireless medium, and self-organization. After more then a decade of tremendous standardization efforts, we can finally witness an integral IP-based WSN standardized protocol stack for IoT. Nevertheless, the current state of standards has redundancy issues and can benefit from further improvements. We would like to highlight some of the cross-layer aspects that need to be considered to bring further improvements to the standardized WSN protocol stack for the IoT.
Net and Prune
Authors: Har-Peled Sariel , Raichel Benjamin
Published: December 2015

We provide a general framework for getting expected linear time constant factor approximations (and in many cases FPTAS's) to several well known problems in Computational Geometry, such as
k
-center clustering and farthest nearest neighbor. The new approach is robust to variations in the input problem, and yet it is simple, elegant, and practical. In particular, many of these well studied problems which fit easily into our framework, either previously had no linear time approximation algorithm, or required rather involved algorithms and analysis. A short list of the problems we consider include farthest nearest neighbor,
k
-center clustering, smallest disk enclosing
k
points,
k
th largest distance,
k
th smallest
m
-nearest neighbor distance,
k
th heaviest edge in the MST and other spanning forest type problems, problems involving upward closed set systems, and more. Finally, we show how to extend our framework such that the linear running time bound holds with high probability.