bluuebunny/crossref_metadata_2025 huggingface dataset:
Chinese Guideline for the Diagnosis and Treatment of Osteonecrosis of the Femoral Head in Adults
Authors:   Microsurgery Department of the Orthopedics Branch of the Chinese Medical Doctor Association,   Group from the Osteonecrosis and Bone Defect Branch of the Chinese Association of Reparative and Reconstructive Surgery,   Microsurgery and Reconstructive Surgery Group of the Orthopedics Branch of the Chinese Medical Association
Published: March 2017

The treatment of adult osteonecrosis of the femoral head (ONFH), with 8.12 million patients in China, remains a challenge to surgeons. To standardize and improve the efficacy of the treatment of ONFH, Chinese specialists updated the experts' suggestions in March 2015, and an experts' consensus was given to provide a current basis for the diagnosis, treatment and evaluation of ONFH. The current guideline provides recommendations for ONFH with respect to epidemiology, etiology, diagnostic criteria, differential diagnosis, staging, treatment, as well as rehabilitation. Risk factors of non‐traumatic ONFH include corticosteroid use, alcohol abuse, dysbarism, sickle cell disease and autoimmune disease and others, but the etiology remains unclear. The Association Research Circulation Osseous (ARCO) staging system, including plain radiograph, magnetic resonance imaging, radionuclide examination, and histological findings, is frequently used in staging ONFH. A staging and classification system was proposed by Chinese scholars in recent years. The major differential diagnoses include mid−late term osteoarthritis, transient osteoporosis, and subchondral insufficiency fracture. Management alternatives for ONFH consist of non‐operative treatment and operative treatment. Core decompression is currently the most common procedure used in the early stages of ONFH. Vascularized bone grafting is the recommended treatment for ARCO early stage III ONFH. This guideline gives a brief account of principles for selection of treatment for ONFH, and stage, classification, volume of necrosis, joint function, age of the patient, patient occupation, and other factors should be taken into consideration.
Safe Zone of Posterior Screw Insertion for Talar Neck Fractures on 3‐Dimensional Reconstruction Model
Authors: Wu Jian‐qun , Ma Sheng‐hui , Liu Song , Qin Cheng‐he , Jin Dan , Yu Bin
Published: March 2017

Objective

To investigate the optimal posterior screw placement and the geometry of safe zones for screw insertion in the talar neck.

Methods

Computed tomography data for 15 normal feet were imported into Mimics 10.01 software for 3‐dimensional reconstruction; 4.0‐mm‐diameter screws were simulated from the lateral tubercle of the posterior process of the talus to the talar head. The range of screw paths trajectories and screw lengths at nine locations that did not breach the cortex of the talus were evaluated. In addition, the farthest (point a) and nearest point (point b) of the safe zone to the subtalar joint at each location, the anteversion angle (angle A), which is parallel to the sagittal plane, and the horizontal angle (angle B), which is perpendicular to the sagittal plane, were measured.

Results

The safe zone was mainly between the 30% location and the 60% location; the width of each safe zone was 13.6° ± 1.4°; the maximum height of each safe zone was 7.8° ± 1.2°. The height of the safe zone was lowest at the 30% location (4.5°) and highest at the 50% location (7.3°). The mixed safe zone of all tali was between the 50% location and the 60% location. When a screw was inserted at point a, the safe entry distance (screw length) ranged from 48.8 to 49.5 mm, and when inserted to point b, the distance ranged from 48.2 to 48.9 mm. And inserting a 48.7 mm screw, 5.6° laterally and 7.4° superiorly, from the lateral tubercle of the posterior process of the talus towards the talar head is safest.

Conclusion

The safe zone of posterior screw fixation have been defined applying to most talus, assuming the fractures are well reduced, this may strengthen the stability, shorten the operation time and reduce the incidence of surgical complications.
Therapeutic Outcomes of KalixIIin Treating Juvenile Flexible Flatfoot
Authors: Cao Le , Miao Xu‐dong , Wu Yong‐ping , Zhang Xiang‐feng , Zhang Qiang
Published: March 2017

Objectives

To evaluate the therapeutic outcomes with KalixIIsubtalar arthroereisis in sinus tarsi for juvenile flexible flatfoot.

Methods

A retrospective analysis of the data of 20 juveniles with symptomatic flexible flatfoot (27 feet) who underwent the KalixIIimplant procedure from January 2008 to September 2012 was performed. The pain during daily activities was assessed and followed up by use of a standard 10‐point visual analog scale (VAS), and function was evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot scoring system, and anteroposterior talar‐first metatarsal angle, lateral talar‐first metatarsal angle, calcaneal pitch angle, and talar declination angle at X‐ray film were measured to assess the therapeutic outcomes. Patients were asked to grade the result of the procedure as excellent, good, fair, or poor at latest follow‐up. The data was expressed as mean ± standard deviation (SD). A paired Student'st‐test was used for comparisons of the preoperative and postoperative angular measurements for each foot,VASscores, andAOFASscores. In all tests,P< 0.05 was considered statistically significant.

Results

The mean age of the patients was 12.1 years (range, 7–16 years), and 16 left feet and 11 right feet were involved. All patients finished the follow‐up with a mean period of 28.1 months (range, 23–60 months). Eleven feet were treated with subtalar arthroereisis combined with reconstruction of the end point of the posterior tibialis tendon after dissection of the accessory scaphoid. The subtalar arthroereisis device displaced in 1 foot due to a fall from the inversion position 3 months after surgery, and was replaced by a new device after the failure of conservative treatment. The meanVASscore decreased from 5.6 ± 0.5 preoperatively to 1.2 ± 0.2 (P< 0.001), and the meanAOFAShindfoot and ankle score improved from 71.1 ± 6.1 preoperatively to 88.1 ± 6.3 (P< 0.001). Differences between preoperative and postoperative measurements for each radiographic variable were statistically significant (P< 0.001). Comparison of radiographic measurements showed that the anteroposterior talar‐first metatarsal (Meary) angle decreased by a mean of 12.8° ± 1.5°, the lateral talar‐first metatarsal (Meary) angle decreased by a mean of 15.4° ± 1.3°, the calcaneal pitch angle increased by a mean of −2.1° ± 0.7°, and the talar declination angle decreased by a mean of 17.9° ± 2.8°. Overall, 12 patients rated the result as excellent, 6 as good, and 2 as fair.

Conclusion

The application of KalixIIin subtalar arthroereisis combined with dissection of accessory scaphoid and reconstruction of posterior tibialis tendon is an effective therapy for flexible juvenile flatfoot.
Rod Migration to the Thoracic Subarachnoid Space after C1–2 Instrumentation: A Case Report and Literature Review
Authors: Dogan Seref , Gundogdu Elif Basaran , Taşkapılıoğlu Mevlüt Özgür , Karaoglu Ahmet
Published: March 2017

Posterior instrumented fusion of the cervical spine is a common surgical procedure in the treatment of cervical subluxation, fractures, and stenosis. Although malpositions are commonly seen, it is rare to observe the malposition of the rod or interconnection because of hardware failure. A 62‐year‐old woman with spastic tetraparesis as a sequel to pediatric meningitis with C1–C2 cervical subluxation and myelomalacia had undergone laminectomy of C1 and C1 lateral mass and C2 bilateral pedicular screw fixation. Three years after the stabilization, she presented with complaints of headache, neck pain, and difficulty walking. There was no history of trauma during that period. A previously unrecorded and unusual migration of a rod through the thoracic subarachnoid space was detected. In this study, we report a case of atlantoaxial stabilization using the screw‐rod technique that was followed by rod migration to the thoracic subarachnoid space, and outline the subsequent management of the case. Failure of bony fusion can result in micromotion and subsequent migration of fixation device components. Routine radiographic follow‐up could be used to identify migration events.
Does Age Impact on Expectations and Concerns of Patients Attending a Chronic Pain Clinic?
Authors: McLoughlin Margaret , Imran Ather , Hannigan Ailish , Harmon Dominic
Published: March 2017

Background

Recognizing expectations and concerns of patients leads to more specialized management plans and greater adherence to treatment and improves outcomes. Little is known about how age impacts on expectations or concerns regarding pain in patients attending a chronic pain clinic.

Methods

We prospectively assessed the expectations and concerns of 100 adult patients at their first visit to a pain clinic. Patients reported their expectations and concerns for the clinic visit using a self‐completed questionnaire. Categories of concerns and expectations were compared across age groups (≤ 65 years, > 65 years) using the chi‐square test and Fisher's exact test.

Results

Thirty‐nine patients (39%) were over 65 years of age (older patients). The most frequently stated site of pain was the lumbar spine for all patients regardless of age. Common concerns of all patients related to sleep and mobility, and the most common expectation related to analgesia. Younger patients were more concerned about employment (23% vs. 3% of older patients, P = 0.005) and social participation (21% vs. 5%, P = 0.03), whereas older patients were more likely to be concerned about mobility (46% vs. 15% of younger patients, P = 0.001). More younger patients expected education on the source of pain than did older patients (23% vs. 3%, P = 0.005), whereas older patients were more likely to be unsure or have no expectations (26% vs. 3%, P = 0.005).

Conclusion

We found differences in patient expectations and concerns by age of those attending a chronic pain clinic. These differences can inform the communication process between physician and patient on treatment plans and outcomes.
A Relational Grounding for (Urban) Governance: Street‐Level Practices of Responsive Improvisation and Practical Change
Authors: Bartels Koen P. R.
Published: March 2017

Related Content: Balfour (PAR May/June 2017)

Related Content: Spicer (PAR May/June 2017)

Related Content: Raadschelders (PAR May/June 2017)

Related Content: Benavides (PAR May/June 2017)
Experimental analysis of the effect of standards on compliance and performance
Authors: Boussalis Constantine , Feldman Yuval , Smith Henry E.
Published: March 2017

Legal directives – whether laws, regulations, or contractual provisions – can be written along a spectrum of specificity, about which behavioral and legal scholarship present conflicting views. We hypothesized that the combination of specificity and monitoring promotes compliance but harms performance and trust, whereas the combination of specificity and good faith enhances both the informative goal‐setting aspects of specificity and people's sense of commitment. To test these hypotheses, we used a 2x2x2 experimental design in which participants were instructed to edit a document with either general or detailed instructions, with a reference to good faith or without it, and with a review of the work or without it. Participants could engage in various levels and kinds of editing, allowing us to distinctly measure both compliance and performance. When participants require information and guidance, as in the case of editing, we found that specificity increases performance relative to the vague standard condition. We discuss the characteristics of the regulatory frameworks in which our findings are especially relevant.
Where Are the Missing Coauthors? Authorship Practices in Participatory Research
Authors: Sarna‐Wojcicki Daniel , Perret Margaret , Eitzel M. V. , Fortmann Louise
Published: March 2017

Originally marginal, participatory research has become an increasingly important methodology in the social, biophysical, and interdisciplinary sciences. The overall increase in publications based on participatory research has raised questions about crediting the contributions of nonacademic collaborators. Using qualitative and quantitative methods, we analyzed trends and patterns in authorship and acknowledgment practices in a sample of 262 journal articles reporting on participatory research on rural livelihoods published from 1975 to 2013. Six percent of the researchers recognized the intellectual contributions of their nonacademic collaborators with coauthorship and 51 percent with acknowledgment. Through interviews with lead authors of coauthored articles, we analyzed factors that shaped whether authorship was shared with nonacademic collaborators. Despite facing numerous barriers, researchers were motivated to coauthor in order to recognize intellectual contributions, practice research ethics, and work toward epistemic decolonization. We argue that coauthorship can be an important component of epistemic justice in participatory research and encourage participatory researchers to discuss authorship with their nonacademic collaborators as a routine component of engaged scholarship. We also note that nonacademics’ contributions to scientific knowledge need to be taken into account in understandings of the practice of science.
Associations between thoracic radiographic changes and severity of pulmonary arterial hypertension diagnosed in 60 dogs via Doppler echocardiography: A retrospective study
Authors: Adams Dustin S. , Marolf Angela J. , Valdés‐Martínez Alejandro , Randall Elissa K. , Bachand Annette M.
Published: March 2017

Doppler echocardiography is a noninvasive method for estimating and grading pulmonary arterial hypertension. No current literature associates significance of radiographic findings with severity of pulmonary arterial hypertension. We hypothesized that the number and conspicuity of radiographic findings suggestive of pulmonary arterial hypertension would be greater based on the severity of pulmonary arterial hypertension. Dogs with pulmonary arterial hypertension and normal control dogs were included in this retrospective, case control study. Three radiologists blinded to echocardiographic results scored thoracic radiographs for right ventricular and main pulmonary artery enlargement and pulmonary lobar artery enlargement, tortuosity, and blunting by multiple methods. Presence or absence of each finding was scored in an additive fashion and averaged for each grade of pulmonary arterial hypertension severity. Seventy‐one dogs (60 dogs with pulmonary arterial hypertension and 11 control dogs) of which some had multiple studies were included: 20 mild, 21 moderate, 25 severe, and 11 absent pulmonary arterial hypertension. The following radiographic findings were significantly associated with increasing pulmonary arterial hypertension severity: right ventricular enlargement by “reverse D” and “3/5–2/5 cardiac ratio” methods, main pulmonary artery enlargement, and caudal lobar artery enlargement by the “3rd rib” method. Mean scores for severe pulmonary arterial hypertension and normal dogs were significantly different (P‐value < 0.0001). Mean scores between different pulmonary arterial hypertension grades increased with severity but were not statistically significant. Individually and in combination, radiographic findings performed poorly in differentiating severity of pulmonary arterial hypertension. Findings indicated that thoracic radiographs should be utilized in conjunction with Doppler echocardiography in a complete diagnostic work‐up for dogs with suspected pulmonary arterial hypertension.
English in Hong Kong higher education
Authors: EVANS STEPHEN
Published: March 2017

Research conducted in the late twentieth century pointed to a gulf in Hong Kong's universities between institutional medium‐of‐instruction policy, which stipulated the use of English, and lecturers’ classroom practices, which often involved the use of Cantonese to present and explain the content of English‐language textbooks and teaching materials. This article examines the findings of a study which sought to determine whether the policy‐practice divide had widened or narrowed in the past two decades under the pressure of two potentially competing forces: globalisation and decolonisation. The evidence suggests that the policy‐practice disjunction may have narrowed significantly in recent years, with most of the participants’ teachers evidently making a determined effort to instruct and interact with their students in English in lectures and seminars.
High-Temperature Interfacial Adhesion Strength Measurement in Electronic Packaging Using the Double Cantilever Beam Method
Authors: Sankarasubramanian Santosh , Cruz Jaime , Yazzie Kyle , Sundar Vaasavi , Subramanian Vijay , Alazar Tsgereda , Yagnamurthy Sivakumar , Cetegen Edvin , McCoy David , Malatkar Pramod
Published: March 2017

This paper describes the use of the double cantilever beam (DCB) method for characterizing the adhesion strength of interfaces in advanced microelectronic packages at room and high temperatures. Those interfaces include silicon–epoxy underfill, solder resist–epoxy underfill and epoxy mold compounds (EMCs), and die passivation materials–epoxy underfill materials. A unique sample preparation technique was developed for DCB testing of each interface in order to avoid the testing challenges specific to that interface—for example, silicon cracking and voiding in silicon–underfill samples and cracking of solder resist films in solder resist–underfill samples. An asymmetric DCB configuration (i.e., different cantilever beam thickness on top compared to the bottom) was found to be more effective in maintaining the crack at the interface of interest and in reducing the occurrence of cohesive cracking when compared to symmetric DCB samples. Furthermore, in order to characterize the adhesion strength of those interfaces at elevated temperatures seen during package assembly and end-user testing, an environmental chamber was designed and fabricated to rapidly and uniformly heat the DCB samples for testing at high temperatures. This chamber was used to successfully measure the adhesion strength of silicon–epoxy underfill samples at temperatures up to 260 °C, which is the typical maximum temperature experienced by electronic packages during solder reflow. For the epoxy underfills tested in this study, the DCB samples failed cohesively within the underfill at room temperature but started failing adhesively at temperatures near 150 °C. Adhesion strength measurements also showed a clear degradation with temperature. Several other case studies using DCB for material selection and assembly process optimization are also discussed. Finally, fractography results of the fractured surfaces are presented for better understanding of the failure mode.
Robust Adaptive Control of Antagonistic Tendon-Driven Joint in the Presence of Parameter Uncertainties and External Disturbances
Authors: Lu Hongqian , Zhang Xu , Huang Xianlin
Published: March 2017

The design of nonlinear tracking controller for antagonistic tendon-driven joint has garnered considerable attention, whereas many existing control methodologies are impractical in the real-time applications due to complexity of computations. In this work, a robust adaptive control method for controlling antagonistic tendon-driven joint is mainly studied by combining adaptive control with mapping filtered forwarding technique. To enhance the robustness of the closed-loop systems, the true viscous friction coefficients are not needed to be known in our controller design. Typically, to tackle the problem of “explosion of complexity,” filters are introduced to bridge the virtual controls such that the controller is decomposed into several submodules. Mappings and their analytic derivatives are computed by these filters, and the mathematical operations of nonlinearities are greatly simplified. The block diagram of this controller of tendon-driven joint is provided, and controller performances are validated through simulations.
Planar nanowires fabricated by thermal gratings on the GaAs(001) surface
Authors: Haghizadeh Anahita , Yang Haeyeon
Published: March 2017

The authors report the fabrication of planar nanowires narrower than 30 nm and longer than a few micrometers, directly on the GaAs(001) surfaces when thermal gratings are created on the surface. The thermal grating is due to the temperature rise that is proportional to the laser intensity modulation, which is produced by interferential irradiation of high power laser pulses. The width of nanowires is much smaller than the laser wavelength as well as the interference period. The results suggest a novel fabrication method of nanowires directly by a single exposure of interferential irradiation of high power laser pulses on the GaAs(001) surfaces.
Predicting the perception of performed dynamics in music audio with ensemble learning
Authors: Elowsson Anders , Friberg Anders
Published: March 2017

By varying the dynamics in a musical performance, the musician can convey structure and different expressions. Spectral properties of most musical instruments change in a complex way with the performed dynamics, but dedicated audio features for modeling the parameter are lacking. In this study, feature extraction methods were developed to capture relevant attributes related to spectral characteristics and spectral fluctuations, the latter through a sectional spectral flux. Previously, ground truths ratings of performed dynamics had been collected by asking listeners to rate how soft/loud the musicians played in a set of audio files. The ratings, averaged over subjects, were used to train three different machine learning models, using the audio features developed for the study as input. The highest result was produced from an ensemble of multilayer perceptrons with an R2 of 0.84. This result seems to be close to the upper bound, given the estimated uncertainty of the ground truth data. The result is well above that of individual human listeners of the previous listening experiment, and on par with the performance achieved from the average rating of six listeners. Features were analyzed with a factorial design, which highlighted the importance of source separation in the feature extraction.
HIV infections are spiking among young gay Chinese
Authors: McLaughlin Kathleen
Published: March 2017

Officials strive to understand infection routes and promote prevention and testing.
Is the cell's garbage disposal sending messages?
Authors: Leslie Mitch
Published: March 2017

Nerve cells may communicate with shredded proteins.
Circular RNAs hint at new realm of genetics
Authors: Servick Kelly
Published: March 2017

Mysterious loops of RNA sometimes serve as templates for unexplored proteins.
AAAS seeks to uphold science's role in policy-making
Authors: Ham Becky
Published: March 2017

Scientists at Annual Meeting urged to build relationships with all levels of government
Harnessing legal complexity
Authors: Ruhl J. B. , Katz Daniel Martin , Bommarito Michael J.
Published: March 2017

Bring tools of complexity science to bear on improving law
Breathing control center neurons that promote arousal in mice
Authors: Yackle Kevin , Schwarz Lindsay A. , Kam Kaiwen , Sorokin Jordan M. , Huguenard John R. , Feldman Jack L. , Luo Liqun , Krasnow Mark A.
Published: March 2017

A tiny group of neurons in the brainstem matches breathing rate to the level of calmness versus arousal.
Science for life
Authors: Alberts Bruce
Published: March 2017

The recent election cycle has made it abundantly clear to most scientists that a large fraction of adults in the United States are surprisingly susceptible to illogical arguments designed to fool them. Research suggests that a great many people assess evidence not as scientists are trained to do, but rather in an emotion-biased manner that is strongly influenced by the beliefs of their cultural cohort. The increasing dominance of social media reinforces this natural human tendency. The consequences are frightening for those who believe that, for humanity to prosper, both personal and community decisions must be based on the best science. This conclusion demands a major rethinking of the goals and methods of science education at all levels—from kindergarten through college.
Use of Ancillary Carbapenemase Tests To Improve Specificity of Phenotypic Definitions for Carbapenemase-Producing Enterobacteriaceae
Authors: Miller Shelley A. , Hindler Janet A. , Chengcuenca Angelo , Humphries Romney M.
Published: March 2017

Carbapenemase-producing
Enterobacteriaceae
(CPE) are a significant threat to public health. In 2015, CDC revised the surveillance definition for CPE to include all
Enterobacteriaceae
resistant to any carbapenem tested. However, this definition is associated with poor specificity. We evaluated the performance of this definition, compared to carbapenemase PCR, for a collection of 125
Enterobacteriaceae
. We also investigated the impact of ancillary testing for carbapenemase of isolates that met the CDC CPE surveillance definition. The two ancillary tests evaluated were the Xpert Carba-R assay, a molecular test, and the carbapenem inactivation method (CIM). Two variables were evaluated for the CIM: suspension of organisms in double-distilled water (ddH
2
O) versus tryptic soy broth (TSB) to incubate disks, and incubation of plates for 6 h versus 18 to 20 h. The sensitivity and specificity of the Carba-R assay were 100% compared to the results of in-house PCR. The sensitivities of the CIM performed with TSB were 94.6% when read at 6 h and 97.7% when read at 18 to 20 h; the sensitivities with ddH
2
O were 88.0% when read at 6 h and 93.0% when incubated for 18 to 20 h. The specificity was 100% for all variables tested. Without ancillary testing, the sensitivity of the CDC definition was 98.9% for CPE, and the specificity was 6.1%. Testing isolates that screened positive by the CDC definition with the Xpert Carba-R did not change the sensitivity, and it improved the specificity to 100%. Similarly, the use of the CIM (TSB and 18 to 20 h of incubation) to confirm screen-positive isolates resulted in a sensitivity of 95.6% and specificity of 100%.
Interactions between the Dengue Virus Polymerase NS5 and Stem-Loop A
Authors: Bujalowski Paul J. , Bujalowski Wlodzimierz , Choi Kyung H.
Published: March 2017

The process of RNA replication by dengue virus is still not completely understood despite the significant progress made in the last few years. Stem-loop A (SLA), a part of the viral 5′ untranslated region (UTR), is critical for the initiation of dengue virus replication, but quantitative analysis of the interactions between the dengue virus polymerase NS5 and SLA in solution has not been performed. Here, we examine how solution conditions affect the size and shape of SLA and the formation of the NS5-SLA complex. We show that dengue virus NS5 binds SLA with a 1:1 stoichiometry and that the association reaction is primarily entropy driven. We also observe that the NS5-SLA interaction is influenced by the magnesium concentration in a complex manner. Binding is optimal with 1 mM MgCl
2
but decreases with both lower and higher magnesium concentrations. Additionally, data from a competition assay between SLA and single-stranded RNA (ssRNA) indicate that SLA competes with ssRNA for the same binding site on the NS5 polymerase. SLA
70
and SLA
80
, which contain the first 70 and 80 nucleotides (nt), respectively, bind NS5 with similar binding affinities. Dengue virus NS5 also binds SLAs from different serotypes, indicating that NS5 recognizes the overall shape of SLA as well as specific nucleotides.

IMPORTANCE
Dengue virus is an important human pathogen responsible for dengue hemorrhagic fever, whose global incidence has increased dramatically over the last several decades. Despite the clear medical importance of dengue virus infection, the mechanism of viral replication, a process commonly targeted by antiviral therapeutics, is not well understood. In particular, stem-loop A (SLA) and stem-loop B (SLB) located in the 5′ untranslated region (UTR) are critical for binding the viral polymerase NS5 to initiate minus-strand RNA synthesis. However, little is known regarding the kinetic and thermodynamic parameters driving these interactions. Here, we quantitatively examine the energetics of intrinsic affinities, characterize the stoichiometry of the complex of NS5 and SLA, and determine how solution conditions such as magnesium and sodium concentrations and temperature influence NS5-SLA interactions in solution. Quantitatively characterizing dengue virus NS5-SLA interactions will facilitate the design and assessment of antiviral therapeutics that target this essential step of the dengue virus life cycle.
Role of Neuraminidase in Influenza A(H7N9) Virus Receptor Binding
Authors: Benton Donald J. , Wharton Stephen A. , Martin Stephen R. , McCauley John W.
Published: March 2017

Influenza A(H7N9) viruses have caused a large number of zoonotic infections since their emergence in 2013. They remain a public health concern due to the repeated high levels of infection with these viruses and their perceived pandemic potential. A major factor that determines influenza A virus fitness and therefore transmissibility is the interaction of the surface glycoproteins hemagglutinin (HA) and neuraminidase (NA) with the cell surface receptor sialic acid. Typically, the HA is responsible for binding to the sialic acid to allow virus internalization and the NA is a sialidase responsible for cleaving sialic acid to aid virus spread and release. N9 NA has previously been shown to have receptor binding properties mediated by a sialic acid binding site, termed the hemadsorption (Hb) site, which is discrete from the enzymatically active sialidase site. This study investigated the N9 NA from a zoonotic H7N9 virus strain in order to determine its possible role in virus receptor binding. We demonstrate that this N9 NA has an active Hb site which binds to sialic acid, which enhances overall virus binding to sialic acid receptor analogues. We also show that the N9 NA can also contribute to receptor binding due to unusual kinetic characteristics of the sialidase site which specifically enhance binding to human-like α2,6-linked sialic acid receptors.

IMPORTANCE
The interaction of influenza A virus glycoproteins with cell surface receptors is a major determinant of infectivity and therefore transmissibility. Understanding these interactions is important for understanding which factors are necessary to determine pandemic potential. Influenza A viruses generally mediate binding to cell surface sialic acid receptors via the hemagglutinin (HA) glycoprotein, with the neuraminidase (NA) glycoprotein being responsible for cleaving the receptor to allow virus release. Previous studies showed that the NA proteins of the N9 subtype can bind sialic acid via a separate binding site distinct from the sialidase active site. This study demonstrates for purified protein and virus that the NA of the zoonotic H7N9 viruses has a binding capacity via both the secondary binding site and unusual kinetic properties of the sialidase site which promote receptor binding via this site and which enhance binding to human-like receptors. This could have implications for understanding human-to-human transmission of these viruses.
Effectors of Filamentous Plant Pathogens: Commonalities amid Diversity
Authors: Franceschetti Marina , Maqbool Abbas , Jiménez-Dalmaroni Maximiliano J. , Pennington Helen G. , Kamoun Sophien , Banfield Mark J.
Published: March 2017

Fungi and oomycetes are filamentous microorganisms that include a diversity of highly developed pathogens of plants. These are sophisticated modulators of plant processes that secrete an arsenal of effector proteins to target multiple host cell compartments and enable parasitic infection. Genome sequencing revealed complex catalogues of effectors of filamentous pathogens, with some species harboring hundreds of effector genes. Although a large fraction of these effector genes encode secreted proteins with weak or no sequence similarity to known proteins, structural studies have revealed unexpected similarities amid the diversity. This article reviews progress in our understanding of effector structure and function in light of these new insights. We conclude that there is emerging evidence for multiple pathways of evolution of effectors of filamentous plant pathogens but that some families have probably expanded from a common ancestor by duplication and diversification. Conserved folds, such as the oomycete WY and the fungal MAX domains, are not predictive of the precise function of the effectors but serve as a chassis to support protein structural integrity while providing enough plasticity for the effectors to bind different host proteins and evolve unrelated activities inside host cells. Further effector evolution and diversification arise via short linear motifs, domain integration and duplications, and oligomerization.
Association of physiological and psychological health outcomes with physical activity and sedentary behavior in adults with type 2 diabetes
Authors: Garcia Jeanette M , Cox Daniel , Rice David J
Published: March 2017

Purpose

To examine the association between change in moderate-to-vigorous physical activity (MVPA) and sedentary behavior (SB) over a 6-month period with physiological and psychological factors in adults with type 2 diabetes (T2D).

Methods

Participants included 26 middle-aged (mean age=56.1±10.8 years; 42% women), overweight/obese (mean body mass index (BMI) =37.22±8.78 kg/m2) adults who had been diagnosed with T2D within the past 5 years (mean HbA1c=7.81%). Participants underwent a physical examination, blood tests, and psychological questionnaires, including a self-report questionnaire that assessed the consumption of high glycemic and low glycemic load foods. Participants wore an Actigraph accelerometer for 7 days to assess MVPA and SB. All measures were collected at baseline and at the 6-month follow-up. Spearman rank correlations and regression models were conducted to examine the relationship between activity variables, and the association of activity measures with health outcomes at the 6-month follow-up.

Results

Decreases in duration of SB bouts and increases in MVPA were associated with decreased levels of HbA1c (p<0.05). Over 50% of the variance in HbA1c levels could be attributed to changes in MVPA and SB.

Conclusions

MVPA and SB were independently associated with diabetes-related health outcomes. Results suggest that emphasis should be placed on increasing MVPA while decreasing SB, particularly duration of SB bouts. This suggests that even small changes in daily behavior may contribute to improvement in diabetes-related health outcomes.
Non-technical skills and gastrointestinal endoscopy: a review of the literature
Authors: Hitchins Charlotte R , Metzner Magdalena , Edworthy Judy , Ward Catherine
Published: March 2017

Background

Non-technical skills (NTS) have gained increasing recognition in recent years for their role in safe, effective team performance in healthcare. Gastrointestinal endoscopy is a procedure-based specialty with rapidly advancing technology, significant operational pressures and rapidly changing ‘teams of experts’. However, to date there has been little focus on the effect of NTS in this field.

Objectives

This review aims to examine the existing literature on NTS in gastrointestinal endoscopy and identify areas for further research.

Method

A systematic search of MEDLINE, Embase, Cochrane Library, PsychINFO, CINAHL Plus and PubMed databases was performed using search terms Non-Technical Skills, Team Performance or Team Skills, and Endoscopy, Colonoscopy, OGD, Gastroscopy, Endoscopic Retrograde Cholangio-Pancreatography or Endoscopic Ultrasound.

Results

Eighteen relevant publications were found. NTS are deemed an essential component of practice, but so far there is little evidence of their integration into training or competency assessment. Those studies examining the effects of NTS and team training in endoscopy are small and have variable outcome measures with limited evidence of improvement in skills or clinical outcomes. NTS assessment in endoscopy is in its early phases with a few tools in development.

Conclusions

The current literature on NTS in gastrointestinal endoscopy is limited. NTS, however, are deemed an essential component of practice, with potential positive effects on team performance and clinical outcomes. A validated reliable tool would enable evaluation of training and investigation into the effects of NTS on outcomes. There is a clear need for further research in this field.
Spectroscopic analysis of CdCl2 doped PVA–PVP blend films
Authors: Baraker Basavarajeshwari M. , Lobo Blaise
Published: March 2017

The changes in molecular chemical structure of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), caused by doping PVA–PVP blend with cadmium chloride (CdCl2), have been studied using ultraviolet–visible (UV-Vis) spectroscopy, Fourier transform Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The formation of cadmium nano-structures and microstructures in CdCl2-doped PVA–PVP blend has been visualized using scanning electron microscopy, in the range of doping levels varying from 0.5 up to 10.2 wt% (doping level in weight percentage). The incorporation of dopant in PVA–PVP blend is confirmed using energy dispersive X-ray spectroscopy. The optical absorbance (UV-Vis) spectra of PVA–PVP blend films doped with CdCl2 from 0.5 up to 2.2 wt%, showed a prominent absorption hump with peak at the wavelength 370 nm, in addition to other intermediate energy bands caused by the interactions of CdCl2 with molecules of PVA and PVP. The photo-luminescence (emission and fluorescence) spectra show significant quenching of fluorescence in CdCl2-doped PVA–PVP blend films. Analysis of FTIR and Raman spectra suggest the possible modes of interaction of cadmium ions (Cd2+) and chlorine ions (Cl−) with reactive functional groups (C–N, hydroxyl and carbonyl groups) of polymeric molecules in the blend. A reaction scheme for interaction of CdCl2 with PVA–PVP blend is proposed, on the basis of spectroscopic studies on these films.
Helicity analysis of single, double, and triple helical iodine chains inside single-walled silicon carbide nanotubes
Authors: Yao Zhen , Liu Chun-Jian , Li Yi , Jing Xiao-Dan , Yuan Quan
Published: March 2017

The helicity of encapsulated single, double, and triple helical iodine chains inside single-walled silicon carbide nanotubes is studied using the van der Waals interaction potential and density functional theory (DFT). Our results show that the optimal radius of the helical iodine chain increases linearly with tube radius, which produces a constant separation between the encapsulated chain and tube wall. The optimal helical angle cannot be determined with a single helical chain, due to the absence of the inter-chain interaction. For the double and triple helical chains, a small optimal helical angle can be induced by a large inter-chain interaction for the same tubes or a large tube for the same chain structure. We also find that the helicity is insensitive to the tube chirality. The DFT calculation further justifies our classical force field analysis and provides a more comprehensive understanding of this helical chains configuration.
Electromagnetic perturbations of a de Sitter black hole in massive gravity
Authors: Fernando Sharmanthie , Manning Amanda
Published: March 2017

The main purpose of this paper is to study quasinormal modes (QNM) of a black hole in massive gravity with a positive cosmological constant due to electromagnetic perturbations. A detailed study of the QNM frequencies for the electromagnetic field is done by varying the parameters of the theory such as the mass, scalar charge, cosmological constant, and the spherical harmonic index. We have employed the sixth-order WKB approximation to calculate the QNM frequencies. The electromagnetic potential for the near extreme massive gravity de Sitter black hole is approximated with the Pöschl–Teller potential to obtain exact frequencies. The null geodesics of the black hole in massive gravity is employed to describe the absorption cross-sections at high-frequency limit.
International Anarchy in Perpetuity? A Re-Examination Based on the Perspectives of Classical Political Thinkers and Ancient Historical Experience
Authors: TANG HSIN-WEI , FENG YUAN
Published: March 2017

Structural realists, notably Waltz and Mearsheimer, have argued for the persistence of an anarchic international political system characterized by the absence of any centralized authority positioned above individual states. Mearsheimer has further suggested that a Sino-U.S. conflict is likely to occur in the future under conditions of anarchy. Based on the perspectives of classical realism, Chinese traditions, and relevant historical experience, we interrogate Mearsheimer’s contention, arguing that hierarchies can thrive under conditions of international anarchy. Thus, international anarchy does not endure in perpetuity.
Vulnerability, Resilience and Transformation of Urban Areas in the Coastal Megacity Lagos: Findings of Local Assessments and a Household Survey in Highly Exposed Areas
Authors: Birkmann Joern , Agboola Julius I. , Welle Torsten , Ahove Michael , Odunuga Shakirudeen , von Streit Joachim , Pelling Mark
Published: March 2017

Coastal urban regions in low-lying areas in developing countries are often hotspots of climate change related risks and therefore the analysis of different characteristics of vulnerability, resilience and transformation is an important prerequisite for planning and decision making. Even though the concepts of resilience and transformation have been discussed for some time, they often remain still very abstract. Against this background the following paper aims to illustrate how different characteristics of vulnerability: susceptibility, exposure and adaptation from resilience to transformative change can be assessed in practice at the level of individual households and different city districts. The household survey was conducted in four low-income, at risk areas in the coastal megacity of Lagos. It reveals important differences between the case study locations in terms of perceived capacities and actual responses of households to extreme events and creeping hazards. The analysis of behavioral changes undertaken after extreme events underscores that experience of loss and damage is an important stimulus for people to change their behavior. Moreover perception of actual and future risk management capacities and the performance of government institutions influences risk management regimes at the household level. It was found that at risk populations experienced both, inaction from government and individual households. This is a corrective to the majority literature that focuses on proactive local or government action. In fact, these examples of success may be quite rare and were not found in the four settlements studied in this research. The survey is part of a larger international project regarding the Transformation and Resilience of Urban Coasts (TRUC (2016). Transformation fo urban coasts Available at www.bel_truc.org ) funded by the Belmont Forum and the DFG in particular in terms of the research in Lagos.
Domain of Attraction Expansion for Physics-Based Character Control
Authors: Borno Mazen Al , Panne Michiel Van De , Fiume Eugene
Published: March 2017

Determining effective control strategies and solutions for high-degree-of-freedom humanoid characters has been a difficult, ongoing problem. A controller is only valid for a subset of the states of the character, known as the
domain of attraction
(DOA). This article shows how many states that are initially outside the DOA can be brought inside it. Our first contribution is to show how DOA expansion can be performed for a high-dimensional simulated character. Our second contribution is to present an algorithm that efficiently increases the DOA using random trees that provide denser coverage than the trees produced by typical sampling-based motion-planning algorithms. The trees are constructed offline but can be queried fast enough for near-real-time control. We show the effect of DOA expansion on getting up, crouch-to-stand, jumping, and standing-twist controllers. We also show how DOA expansion can be used to connect controllers together.
Intracellular Nucleic Acid Detection in Autoimmunity
Authors: Crowl John T. , Gray Elizabeth E. , Pestal Kathleen , Volkman Hannah E. , Stetson Daniel B.
Published: March 2017

Protective immune responses to viral infection are initiated by innate immune sensors that survey extracellular and intracellular space for foreign nucleic acids. The existence of these sensors raises fundamental questions about self/nonself discrimination because of the abundance of self-DNA and self-RNA that occupy these same compartments. Recent advances have revealed that enzymes that metabolize or modify endogenous nucleic acids are essential for preventing inappropriate activation of the innate antiviral response. In this review, we discuss rare human diseases caused by dysregulated nucleic acid sensing, focusing primarily on intracellular sensors of nucleic acids. We summarize lessons learned from these disorders, we rationalize the existence of these diseases in the context of evolution, and we propose that this framework may also apply to a number of more common autoimmune diseases for which the underlying genetics and mechanisms are not yet fully understood.
Nitric oxide-sensitive guanylyl cyclase signaling affects CO2-dependent but not pressure-dependent regulation of cerebral blood flow
Authors: Jahshan Shadi , Dayan Lior , Jacob Giris
Published: March 2017

Cerebrovascular CO2reactivity is affected by nitric oxide (NO). We tested the hypothesis that sildenafil selectively potentiates NO-cGMP signaling, which affects CO2reactivity. Fourteen healthy males (34 ± 2 yr) were enrolled in the study. Blood pressure (BP), ECG, velocity of cerebral blood flow (CBF; measured by transcranial Doppler), and end-tidal CO2(EtCO2) were assessed at baseline (CO2~39 mmHg), during hyperventilation (CO2~24 mmHg), during hypercapnia (CO2~46 mmHg), during boluses of phenylephrine (25–200 µg), and during graded head-up tilting (HUT). Measurements were repeated 1 h after 100 mg sildenafil were taken. Results showed that sildenafil did not affect resting BP, heart rate, CBF peak and mean velocities, estimated regional cerebrovascular resistance (eCVR; mean BP/mean CBF), breath/min, and EtCO2: 117 ± 2/67 ± 3 mmHg, 69 ± 3 beats/min, 84 ± 5 and 57 ± 4 cm/s, 1.56 ± 0.1 mmHg·cm−1·s−1, 14 ± 0.5 breaths/min, and 39 ± 0.9 mmHg, respectively. Sildenafil increased and decreased the hypercapnia induced in CBF and eCVR, respectively. Sildenafil also attenuated the decrease in peak velocity of CBF, 25 ± 2 vs. 20 ± 2% ( P < 0.05) and increased the eCVR, 2.5 ± 0.2 vs. 2 ± 0.2% ( P < 0.03) during hyperventilation. Sildenafil did not affect CBF despite significant increases in the eCVRs that were elicited by phenylephrine and HUT. This investigation suggests that sildenafil, which potentiates the NO-cGMP signaling, seems to affect the cerebrovascular CO2reactivity without affecting the static and dynamic pressure-dependent mechanisms of cerebrovascular autoregulation.