bluuebunny/crossref_metadata_2025 huggingface dataset:
Secrecy performance of hybrid satellite‐terrestrial relay networks in the presence of multiple eavesdroppers
Authors: Huang Qingquan , Lin Min , An Kang , Ouyang Jian , Zhu Wei‐Ping
Published: November 2017

This study investigates the secrecy performance of a hybrid satellite‐terrestrial relay network (HSTRN) in the presence of multiple eavesdroppers, where the satellite link undergoes Shadowed‐Rician fading, while the terrestrial link follows Rayleigh fading. The authors suppose the direct link between the satellite and the intended user is unavailable due to heavy shadowing and adopt a multi‐antenna relay using either a decode‐and‐forward (DF) or an amplify‐and‐forward (AF) protocol to assist the transmission. By employing perfect channel state information of each link at the relay, the authors first apply receive maximal ratio combining beamforming (BF) and transmit zero‐forcing BF schemes to obtain the output signal‐to‐noise ratios (SNRs) of the intended user and eavesdroppers. Then, based on the Meijer‐G function and the moment generating function, the authors derive the analytical expressions of the ergodic secrecy rate for the considered HSTRN for both DF and AF protocols. Finally, Monte‐Carlo simulations are conducted to validate the theoretical performance analysis and reveal the effects of certain representative parameters on the system secrecy performance.
Mitigation of switching overvoltages in microgrids based on SVC and supercapacitor
Authors: Awad Eman A. , Badran Ebrahim A. , Youssef Fathi H.
Published: November 2017

This study investigates three different techniques to mitigate the switching overvoltages (SOVs) in the microgrids. At first, the effectiveness of reactive power compensation devices, such as static var compensator (SVC), is evaluated. After that, the performance of the supercapacitor (SC), as an energy storage device, is studied. Finally, with the addition of the SVC to the SC, the possibility to mitigate SOV by compensating both active and reactive power simultaneously is investigated. SOVs result due to unsymmetrical switching operation during de‐energisation (disconnection) procedures. The μG two operational modes; grid connected mode and isolated mode, are considered. A small hydro generation unit and three variable speed, double‐fed induction generator‐based wind turbines are the main renewable power generation units in the tested microgrid system. Alternative Transient Program is used in this study for simulating the compensation device, the energy storage device and the investigated microgrid. The study shows that through the μG two operational modes, the SC has priority over the other two investigated mitigation methods. Furthermore, using the SC or SC with SVC, the results have more regular voltage waveforms.
Delay‐aware data collecting protocol for low‐duty‐cycle wireless sensor networks
Authors: He Hua , Xu Zhen , Yang Lei
Published: October 2017

Duty‐cycled technology has been introduced as an efficient way to preserve node energy and prolong network lifetime for wireless sensor networks (WSNs). However, many applications with real‐time feature require that some message must be sent to the sink node within a limited time. The authors propose a novel data collecting scheme – MTDR which aims to minimise transmission delay in low‐duty‐cycle WSNs. In MTDR, all the nodes are assigned to the corresponding levels according to the hop count to the sink node, and calculate their minimum transmission delay to the sink node based on the shortest path structure. Finally, simulation results show that their proposed algorithm can achieve better performance compared with some related works.
Sufficiency and sensitivity for nonlinear optimal control problems on time scales via coercivity
Authors: Šimon Hilscher Roman , Zeidan Vera
Published: October 2017

The main focus of this paper is to develop a sufficiency criterion for optimality in nonlinear optimal control problems defined on time scales. In particular, it is shown that the coercivity of the second variation together with the controllability of the linearized dynamic system are sufficient for the weak local minimality. The method employed is based on a direct approach using the structure of this optimal control problem. The second aim pertains to the sensitivity analysis for parametric control problems defined on time scales with separately varying state endpoints. Assuming a slight strengthening of the sufficiency criterion at a base value of the parameter, the perturbed problem is shown to have a weak local minimum and the corresponding multipliers are shown to be continuously differentiable with respect to the parameter. A link is established between (i) a modification of the shooting method for solving the associated boundary value problem, and (ii) the sufficient conditions involving the coercivity of the accessory problem, as opposed to the Riccati equation, which is also used for this task. This link is new even for the continuous time setting.
Three-dimensional Fusion Imaging without Contrast Medium for Carotid Endarterectomy
Authors: Mizutani Tohru , Sumi Kenji , Shimizu Katsuyoshi , Matsumoto Masaki
Published: November 2017

Carotid endarterectomy (CEA) is a popular surgical procedure for patients with carotid artery stenosis. Before performing CEA, radiologic information about carotid artery stenosis must be obtained using three-dimensional (3D) computed tomography angiography (CTA). However, it is difficult to perform 3D-CTA in patients with renal dysfunction and an allergy to contrast medium. To solve this problem, 3D fusion images (3D-FI) with magnetic resonance angiography and 3D computed tomography are created. In this report, we describe the utility of 3D-FI.
Rates and Locations of Regional Metastases in Sinonasal Malignancies: The Mayo Clinic Experience
Authors: Peck Brandon , Van Abel Kathryn , Moore Eric , Price Daniel
Published: November 2017

Objectives The objective of this study was to identify factors that may influence the rate and location of regional metastasis in sinonasal malignancies (SNMs).

Design This is a retrospective review.

Setting This study was set at the single-institution tertiary referral center.

Participants A total of 299 patients were treated for SNMs from 1994 to 2014.

Main Outcome Measures The main outcome measures were incidence and distribution of regional metastases.

Results Several histologic subtypes were treated, with squamous cell carcinoma (28.4%), esthesioneuroblastoma (18.1%), and mucosal melanoma (12.4%) being the most common. Of the 299 patients, 59 (19.7%) developed a regional metastasis, either at presentation or during follow-up. Higher cumulative incidence of regional metastases was significantly associated with histologic type (p ≤0.001) and invasion of the dura (p = 0.005), infratemporal fossa (p = 0.036), orbit (p = 0.020), or palate (p = 0.016). Ipsilateral level II lymph nodes were the most commonly involved nodes. Contralateral regional metastases were associated with higher risk histologic types (p = 0.005) and dural invasion (p = 0.008). Parotid metastases were associated with invasion of the facial soft tissue (p = 0.028), and retropharyngeal metastases were associated with invasion of the pterygoid plates and musculature (p = 0.030).

Conclusion Histologic type of SNM appears to be the most important factor in predicting the rate of regional metastases. Histologic type and invasion of certain neighboring structures may help define which lymphatic basins are at highest risk for metastasis.
Locoregional Therapy for Hepatic Neuroendocrine Metastases
Authors: Bercu Zachary , Mitchell Jason , Camacho Juan , Kies Darren , Friedberg Eric , Martin Charles , Prologo J.
Published: November 2017

Neuroendocrine tumors are a heterogeneous group of malignancies with diverse biological and clinical behavior. Locoregional treatments available for the initial and temporal management of neuroendocrine tumors involving the liver include transarterial embolization, transarterial chemoembolization, selective internal radiotherapy, and ablative techniques. These therapies are best employed as part of a multidisciplinary management team focusing on appropriate histopathology, timing, and individuality of each intervention.
Transient energy growth of optimal streaks in parallel round jets
Authors: Jiménez-González J. I. , Brancher P.
Published: November 2017

We present a linear optimal perturbation analysis of streamwise invariant disturbances evolving in parallel round jets. The potential for transient energy growth of perturbations with azimuthal wavenumber m≥1 is analyzed for different values of Reynolds number Re. Two families of steady (frozen) and unsteady (diffusing) base flow velocity profiles have been used, for different aspect ratios α = R/θ, where R is the jet radius and θ is the shear layer momentum thickness. Optimal initial conditions correspond to infinitesimal streamwise vortices, which evolve transiently to produce axial velocity streaks, whose spatial structure and intensity depend on base flow and perturbation parameters. Their dynamics can be characterized by a maximum optimal value of the energy gain Gopt, reached at an optimal time τopt after which the perturbations eventually decay. Optimal energy gain and time are shown to be, respectively, proportional to Re2 and Re, regardless of the frozen or diffusing nature of the base flow. Besides, it is found that the optimal gain scales like Gopt∝1/m3 for all m except m = 1. This quantitative difference for azimuthal wavenumber m = 1 is shown to be based on the nature of transient mechanisms. For m = 1 perturbations, the shift-up effect [J. I. Jiménez-González et al., “Modal and non-modal evolution of perturbations for parallel round jets,” Phys. Fluids 27, 044105-1–044105-19 (2015)] is active: an initial streamwise vorticity dipole induces a nearly uniform velocity flow in the jet core, which shifts the whole jet radially. By contrast, optimal perturbations with m≥2 are concentrated along the shear layer, in a way that resembles the classical lift-up mechanism in wall-shear flows. The m = 1 shift-up effect is more energetic than the m≥2 lift-up, but it is slower, with optimal times considerably shorter in the case of m≥2 disturbances. This suggests that these perturbations may emerge very quickly in the flow when injected as initial conditions. When the base flow diffuses, the large time scale for m = 1 disturbances allows the shear layer to spread and the jet core velocity to decrease substantially, thus lowering the values of corresponding optimal gain and time. For m≥2, results are less affected, since the shorter transient dynamics does not leave room for significant modifications of the base flow velocity profiles, and the scaling laws obtained in the frozen case are recovered. Nevertheless, base flow diffusion hinders the transient growth, as a consequence of a weaker component-wise non-normality and a smoother, radially spread structure of optimal disturbances.
Going beyond the standard line tension: Size-dependent contact angles of water nanodroplets
Authors: Kanduč Matej
Published: November 2017

The dependence of the contact angle on the size of a nanoscopic droplet residing on a flat substrate is traditionally ascribed solely to line tension. Other contributions, stemming from the droplet geometry dependence of the surface tension and line tension, are typically ignored. Here, we perform molecular dynamics simulations of water droplets of cylindrical morphology on surfaces of a wide range of polarities. In the cylindrical geometry, where the line tension is not operative directly, we find significant contact angle dependence on the droplet size. The effect is most pronounced on hydrophilic surfaces, with the contact angle increase of up to 10° with a decreasing droplet size. On hydrophobic surfaces, the trend is reversed and considerably weaker. Our analysis suggests that these effects can be attributed to the Tolman correction due to the curved water–vapor interface and to a generalized line tension that possesses a contact angle dependence. The latter is operative also in the cylindrical geometry and yields a comparable contribution to the contact angle as the line tension itself in case of spherical droplets.
Mutual 3:1 subharmonic synchronization in a micromachined silicon disk resonator
Authors: Taheri-Tehrani Parsa , Guerrieri Andrea , Defoort Martial , Frangi Attilio , Horsley David A.
Published: November 2017

We demonstrate synchronization between two intrinsically coupled oscillators that are created from two distinct vibration modes of a single micromachined disk resonator. The modes have a 3:1 subharmonic frequency relationship and cubic, non-dissipative electromechanical coupling between the modes enables their two frequencies to synchronize. Our experimental implementation allows the frequency of the lower frequency oscillator to be independently controlled from that of the higher frequency oscillator, enabling study of the synchronization dynamics. We find close quantitative agreement between the experimental behavior and an analytical coupled-oscillator model as a function of the energy in the two oscillators. We demonstrate that the synchronization range increases when the lower frequency oscillator is strongly driven and when the higher frequency oscillator is weakly driven. This result suggests that synchronization can be applied to the frequency-selective detection of weak signals and other mechanical signal processing functions.
Light-induced reversible expansion of individual gold nanoplates
Authors: Lu Jinsheng , Hong Yu , Li Qiang , Xu Yingxin , Fang Wei , Qiu Min
Published: October 2017

Light-induced mechanical response of materials has been extensively investigated and widely utilized to convert light energy into mechanical energy directly. The metallic nanomaterials have excellent photothermal properties and show enormous potential in micromechanical actuators, etc. However, the photo-thermo-mechanical properties of individual metallic nanostructures have yet to be well investigated. Here, we experimentally demonstrate a way to realize light-induced reversible expansion of individual gold nanoplates on optical microfibers. The light-induced thermal expansion coefficient is obtained as 21.4 ± 4.6 ∼ 31.5 ± 4.2 μ·K-1 when the light-induced heating temperature of the gold nanoplates is 240 ∼ 490 °C. The photo-thermo-mechanical response time of the gold nanoplates is about 0.3 ± 0.1 s. This insight into the photo-thermo-mechanical properties of the gold nanoplates could deepen the understanding of the light-induced reversible expansion behavior in nanoscale and pave the way for applications based on this piezoelectric-like response, such as light-driven metallic micromotors.
Ontology based heterogeneous materials database integration and semantic query
Authors: Zhao Shuai , Qian Quan
Published: October 2017

Materials digital data, high throughput experiments and high throughput computations are regarded as three key pillars of materials genome initiatives. With the fast growth of materials data, the integration and sharing of data is very urgent, that has gradually become a hot topic of materials informatics. Due to the lack of semantic description, it is difficult to integrate data deeply in semantic level when adopting the conventional heterogeneous database integration approaches such as federal database or data warehouse. In this paper, a semantic integration method is proposed to create the semantic ontology by extracting the database schema semi-automatically. Other heterogeneous databases are integrated to the ontology by means of relational algebra and the rooted graph. Based on integrated ontology, semantic query can be done using SPARQL. During the experiments, two world famous First Principle Computational databases, OQMD and Materials Project are used as the integration targets, which show the availability and effectiveness of our method.
A pinhole camera for ultrahigh-intensity laser plasma experiments
Authors: Wang C. , An H. H. , Xiong J. , Fang Z. H. , Wang Y. W. , Zhang Z. , Hua N. , Sun J. R. , Wang W.
Published: November 2017

A pinhole camera is an important instrument for the detection of radiation in laser plasmas. It can monitor the laser focus directly and assist in the analysis of the experimental data. However, conventional pinhole cameras are difficult to use when the target is irradiated by an ultrahigh-power laser because of the high background of hard X-ray emission generated in the laser/target region. Therefore, an improved pinhole camera has been developed that uses a grazing-incidence mirror that enables soft X-ray imaging while avoiding the effect of hard X-ray from hot dense plasmas.
Magneto-optical imaging reveals impacts of niobium preparation for superconducting performance
Authors: Cockbill Louisa
Published: November 2017

Researchers developed a magneto-optical imaging method to analyze magnetic flux properties of superconducting niobium, revealing the effects of heat treatment on its trapped flux distribution.
Ancient clues help quantify modern methane
Authors: Miller Johanna L.
Published: October 2017

Natural geological emissions contributed little to the methane levels of the ancient atmosphere. The same could be true today.
Da Vinci’s observations of soaring birds
Authors: Richardson Philip L.
Published: October 2017

More than half a millennium ago, the great polymath Leonardo da Vinci sketched and described a maneuver that birds use to extract energy from a gradient in wind speed.
Norovirus and cruise ships
Authors: Lun Jennifer H , Ressler Kelly-Anne , Ferson Mark J , White Peter A
Published: October 2017

Acute gastroenteritis (AGE) is one of the most common diseases of humans in both developed and developing countries. Despite the improved safety of food handling and prevention strategies, it remains one of the most significant health burdens on society1. An estimated 1.8 million AGE-associated deaths occur annually worldwide2,3, making it the leading cause of mortality among children under the age of five years. In this article, we examine recent trends in emerging noroviruses, the ability of the virus to cause outbreaks on cruise ships and discuss the factors that influence its on-board spread.
Microstructure and mechanical properties of austempered AISI 9255 high-silicon steel
Authors: Acharya Palaksha Pilar , Udupa Rajendra , Bhat Ravishankar
Published: November 2017

The present investigation is focused on evaluating the microstructure and mechanical properties of American Iron and Steel Institute 9255 high-silicon steel austempered at different temperatures and durations. Material characterisation was done using a scanning electron microscope and an X-ray diffractometer. Results show the bainite microstructure over a temperature range of 280–400°C. Bainite structure gains coarseness at higher temperatures at 360 and 400°C. A significant improvement in the tensile properties was observed for all austempered specimens; with a maximum tensile strength of 1852 MPa and elongation up to 35%. An excellent strain hardening response was observed from the samples austempered at temperatures of 360 and 400°C. Tensile properties were found to be superior at 15 min of austempering duration for all austempering temperatures.
Application of texture inheritance on manufacturing ultra-high strength pearlitic steel wire
Authors: Fang Feng , Wang Liping , Zhou Lichu , Min Xuegang , Jiang Jianqing
Published: November 2017

To obtain both ultra-high strength and good ductility in pearlitic steel wires, a new processing technique was proposed following the principle of inherited texture. Microstructure evolution of pearlitic wires was investigated by FE-SEM, EBSD and TEM, and while mechanical properties were determined by tensile and torsional tests. Two types of wires with different ferrite <110> texture intensity were obtained by varying pre-drawing strain. The orientation between ferrite <110> and drawing direction exhibited a great effect on the deformation behaviour of pearlite. For the ferrite <110> parallel to drawing direction, cementite lamellae were straightened and dislocations within ferrite were evenly distributed. However, for the ferrite <110> at an angle to drawing direction, the cementite was bent and the distribution of dislocations within ferrite was uneven. Consequently, pearlitic wires with a higher texture level exhibited an extremely high tensile strength, coupled with a remarkable torsion tolerance.

This is part of a thematic issue on Pearlitic Steel Wires.
Application of response surface methodology for optimizing evacuation time in enclosed car park
Authors: Tharima Ahmad Faiz , Rahman Md Mujibur , Yusoff Mohd Zamri
Published: November 2017

Smoke fills the car park area due to smoke back layering occurred during a fire. The presence of the beam which leads to the smoke back layering phenomena is investigated to remain smoke layer longer at the upper level with fewer occurrences of backflow. In the current study, a combination of Design of Experiment (DOE); Central Composite Design, (CCD) and statistical tools Response Surface Methodology, (RSM) were utilised to evaluate an optimal design for longer smoke residing time. The Fire Dynamic Simulator (FDS), a CFD model for the fire-driven fluid flow, was employed as a flow simulation tool. The result of six replication model produced by DOE, the error that ranged from 0.48% to 1.77% indicating that the model is reliable. It was also found that the polynomial regression result was linear with predicted R2 of 97.64%, which was within the actual R2 (99.45%). The effects of five control parameters such as ceiling height, beam spacing, transversal beam, extraction rate and longitudinal beam on the smoke descend time has been found to be significant. In the optimal design, the smoke remained longer at the upper level with the percentage of improvement 217.95%. The contribution of the study is the time measured in this analysis is adequate within the beam span only. Interestingly, it effects to the overall geometry with having a lengthier time of smoke to descend. The polynomial model should be used for future engineering design in an enclosed car park.
Estimation of QTL heritability based on pooled sequencing data
Authors: Tang Weiqi , Huang Likun , Bu Suhong , Zhang Xuzhang , Wu Weiren
Published: November 2017

Motivation

Bulked segregant analysis combined with next generation sequencing has proven to be a simple and efficient approach for fast mapping of quantitative trait loci (QTLs). However, how to estimate the proportion of phenotypic variance explained by a QTL (or termed QTL heritability) in such pooled QTL mapping is an unsolved problem.

Results

In this paper, we propose a method called PQHE to estimate QTL heritability using pooled sequencing data obtained under different experimental designs. Simulation studies indicated that our method is correct and feasible. Four practical examples from rice and yeast are demonstrated, each representing a different situation.

Availability and implementation

The R scripts of our method are open source under GPLv3 license at http://genetics.fafu.edu.cn/PQHE or https://github.com/biotangweiqi/PQHE. The R scripts require the R package rootSolve.

Supplementary information

Supplementary data are available at Bioinformatics online.
Using Contact Theory to Assess Staff Perspectives on Training Initiatives of an Intergenerational Programming Intervention
Authors: Weaver Raven H , Naar Jill J , Jarrott Shannon E
Published: November 2017

Background and Objectives

Project TRIP (Transforming Relationships through Intergenerational Programs) was developed as a sustainable intergenerational community project involving child care participants and elders attending an elder care program or volunteering at the children’s program. The project focused on staff development of evidence-based intergenerational practices. To enhance available intervention research, contact theory provided a theoretical framework to explore how staff members’ and administrators’ perceptions of the intervention influenced their ability to implement programming in social care settings.

Research Design and Methods

We used a directed content analysis approach to analyze small group and individual interviews with 32 participants from 6 program sites over 5 years.

Results

Participants highlighted inherent challenges and subsequent benefits of academic–community partnerships. Greater on-site presence, open communication, and relationship-building proved critical to improve community partnerships, project fidelity, and program sustainability. When interactions reflected contact theory tenets, collaborators reported positive attitudes toward and interactions with research partners.

Discussion and Implications

Contact theory provided a useful framework to understand the researcher–practitioner partnership. Researchers should plan for partnerships that: (a) are supported by authority figures, including staff and participants, (b) utilize a shared expertise approach where partners have equal group status, (c) involve close cooperation; (d) align research and program goals, and (e) foster positive communication through frequent contact using practitioners’ preferred methods and including in-person contact. We recommend future intergenerational programming interventions build on a foundation of both theory and practice.
Robotic Stereotaxy in Cranial Neurosurgery: A Qualitative Systematic Review
Authors: Fomenko Anton , Serletis Demitre
Published: November 2017

BACKGROUND

Modern-day stereotactic techniques have evolved to tackle the neurosurgical challenge of accurately and reproducibly accessing specific brain targets. Neurosurgical advances have been made in synergy with sophisticated technological developments and engineering innovations such as automated robotic platforms. Robotic systems offer a unique combination of dexterity, durability, indefatigability, and precision.

OBJECTIVE

To perform a systematic review of robotic integration for cranial stereotactic guidance in neurosurgery. Specifically, we comprehensively analyze the strengths and weaknesses of a spectrum of robotic technologies, past and present, including details pertaining to each system's kinematic specifications and targeting accuracy profiles.

METHODS

Eligible articles on human clinical applications of cranial robotic-guided stereotactic systems between 1985 and 2017 were extracted from several electronic databases, with a focus on stereotactic biopsy procedures, stereoelectroencephalography, and deep brain stimulation electrode insertion.

RESULTS

Cranial robotic stereotactic systems feature serial or parallel architectures with 4 to 7 degrees of freedom, and frame-based or frameless registration. Indications for robotic assistance are diversifying, and include stereotactic biopsy, deep brain stimulation and stereoelectroencephalography electrode placement, ventriculostomy, and ablation procedures. Complication rates are low, and mainly consist of hemorrhage. Newer systems benefit from increasing targeting accuracy, intraoperative imaging ability, improved safety profiles, and reduced operating times.

CONCLUSION

We highlight emerging future directions pertaining to the integration of robotic technologies into future neurosurgical procedures. Notably, a trend toward miniaturization, cost-effectiveness, frameless registration, and increasing safety and accuracy characterize successful stereotactic robotic technologies.
Galaxy interactions trigger rapid black hole growth: An unprecedented view from the Hyper Suprime-Cam survey
Authors: Goulding Andy D , Greene Jenny E , Bezanson Rachel , Greco Johnny , Johnson Sean , Leauthaud Alexie , Matsuoka Yoshiki , Medezinski Elinor , Price-Whelan Adrian M
Published: October 2017

Collisions and interactions between gas-rich galaxies are thought to be pivotal stages in their formation and evolution, causing the rapid production of new stars, and possibly serving as a mechanism for fueling supermassive black holes (BHs). Harnessing the exquisite spatial resolution (∼0${^{\prime\prime}_{.}}$5) afforded by the first ∼170 deg2 of the Hyper Suprime-Cam (HSC) survey, we present our new constraints on the importance of galaxy–galaxy major mergers (1 : 4) in growing BHs throughout the last ∼8 Gyr. Utilizing mid-infrared observations in the WISE all-sky survey, we robustly select active galactic nuclei (AGN) and mass-matched control galaxy samples, totaling ∼140000 spectroscopically confirmed systems at i < 22 mag. We identify galaxy interaction signatures using a novel machine-learning random forest decision tree technique allowing us to select statistically significant samples of major mergers, minor mergers / irregular systems, and non-interacting galaxies. We use these samples to show that galaxies undergoing mergers are a factor of ∼2–7 more likely to contain luminous obscured AGN than non-interacting galaxies, and this is independent of both stellar mass and redshift to z < 0.9. Furthermore, based on our comparison of AGN fractions in mass-matched samples, we determine that the most luminous AGN population (LAGN ≳ 1045 erg s−1) systematically reside in merging systems over non-interacting galaxies. Our findings show that galaxy–galaxy interactions do, on average, trigger luminous AGN activity substantially more often than in secularly evolving non-interacting galaxies, and we further suggest that the BH growth rate may be closely tied to the dynamical time of the merger system.
Potyviral Gene-Silencing Suppressor HCPro Interacts with Salicylic Acid (SA)-Binding Protein 3 to Weaken SA-Mediated Defense Responses
Authors: Poque Sylvain , Wu Hui-Wen , Huang Chung-Hao , Cheng Hao-Wen , Hu Wen-Chi , Yang Jun-Yi , Wang David , Yeh Shyi-Dong
Published: November 2017

The viral infection process is a battle between host defense response and pathogen antagonizing action. Several studies have established a tight link between the viral RNA silencing suppressor (RSS) and the repression of salicylic acid (SA)-mediated defense responses, nonetheless host factors directly linking an RSS and the SA pathway remains unidentified. From yeast two-hybrid analysis, we identified an interaction between the potyviral RSS helper-component proteinase (HCPro) and SA–binding protein SABP3. Co-localization and bimolecular fluorescence complementation analyses validated the direct in vivo interaction between Turnip mosaic virus (TuMV) HCPro and the Arabidopsis homologue of SABP3, AtCA1. Additionally, transient expression of TuMV HCPro demonstrated its ability to act as a negative regulator of AtCA1. When the plants of the AtCA1 knockout mutant line were inoculated with TuMV, our results indicated that AtCA1 is essential to restrict viral spreading and accumulation, induce SA accumulation, and trigger the SA pathway. Unexpectedly, the AtCA1 overexpression line also displayed a similar phenotype, suggesting that the constitutive expression of AtCA1 antagonizes the SA pathway. Taken together, our results depict AtCA1 as an essential regulator of SA defense responses. Moreover, the interaction of potyviral HCPro with this regulator compromises the SA pathway to weaken host defense responses and facilitate viral infection.
Cervical Sagittal Range of Motion as a Predictor of Symptom Severity in Cervical Spondylotic Myelopathy
Authors: Nicholson Kristen J. , Millhouse Paul W. , Pflug Emily , Woods Barrett , Schroeder Gregory D. , Anderson D. Greg , Hilibrand Alan S. , Kepler Christopher K. , Kurd Mark F. , Rihn Jeffrey A. , Vaccaro Alexander , Radcliff Kris E.
Published: November 2017

Study Design.

A retrospective review of radiographic data and functional outcomes.

Objective.

The aim of this study was to evaluate whether myelopathy symptom severity upon presentation corresponds to sagittal plane alignment or nonmyelopathy symptoms, such as pain, in patients with cervical spondylotic myelopathy (CSM).

Summary of Background Data.

Cervical sagittal balance is an important parameter in the outcome of surgical reconstruction. However, the effect of sagittal alignment on symptom severity in patients who have not undergone spine surgery is not well defined.

Methods.

A consecutive series of CSM patients was identified at an academic institution. Preoperative radiographs were analyzed for sagittal vertical axis (C2SVA), C7 slope (C7S), C2-C7 angle in neutral (C27N), flexion (C27F), and extension (C27E), and range of motion (C27ROM). Neutral alignment was categorized as lordotic, kyphotic, or sigmoid/straight. Outcomes collected were SF-12, neck disability index, arm pain, neck pain, and modified JOA (mJOA). Pearson coefficients determined correlations between radiographic and outcome parameters. Multivariate regression evaluated predictive factors of mJOA.

Results.

Radiographic parameters did not correlate with pain. Increasing age, smaller C27ROM, and smaller flexion angles correlated to lower (more severe) baseline mJOA scores. ROM (and not static alignment) was the only significant predictor of mJOA in the multivariate regression. Despite significant radiographic differences between lordotic, kyphotic, and sigmoid/straight alignment groups, myelopathy severity did not differ between these groups.

Conclusion.

Static, neutral alignment, including SVA and lordosis, did not correlate with myelopathy or pain symptoms. Greater C27ROM and increased maximal flexion corresponded to milder myelopathy symptoms, suggesting that patients with myelopathy may compensate for cervical stenosis with hyperflexion, similar to that which is observed in the lumbar spine. In a CSM patient population, dynamic motion and compensatory deformities may play a more significant role in myelopathy symptom severity than what can be discerned from standard, neutral position radiographs.

Level of Evidence: 3
Important Role of Endothelial Caveolin-1 in the Protective Role of Endothelium-dependent Hyperpolarization Against Nitric Oxide–Mediated Nitrative Stress in Microcirculation in Mice
Authors: Saito Hiroki , Godo Shigeo , Sato Saori , Ito Akiyo , Ikumi Yosuke , Tanaka Shuhei , Ida Tomoaki , Fujii Shigemoto , Akaike Takaaki , Shimokawa Hiroaki
Published: November 2017

Aims:

Nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) play important roles in maintaining cardiovascular homeostasis. We have previously demonstrated that endothelial NO synthase (eNOS) plays diverse roles depending on vessel size, as a NO generating system in conduit arteries and an EDH-mediated system in resistance arteries, for which caveolin-1 (Cav-1) is involved. However, the physiological role of endothelial Cav-1 in microvessels remains to be elucidated.

Methods and Results:

We newly generated endothelium-specific Cav-1-knockout (eCav-1-KO) mice. eCav-1-KO mice showed loss of endothelial Cav-1/eNOS complex and had cardiac hypertrophy despite normal blood pressure. In eCav-1-KO mice, as compared to wild-type controls, the extent of eNOS phosphorylation at inhibitory Thr495 was significantly reduced in mesenteric arteries and the heart. Isometric tension and Langendorff-perfused heart experiments showed that NO-mediated responses were enhanced, whereas EDH-mediated responses were reduced in coronary microcirculation in eCav-1-KO mice. Immunohistochemistry showed increased level of 8-nitroguanosine 3′,5′-cyclic monophosphate (8-nitro-cGMP), a marker of nitrative stress, in the heart from eCav-1-KO mice. S-guanylation of cardiac H-Ras in eCav-1-KO mice was also significantly increased compared with wild-type controls.

Conclusions:

These results suggest that eCav-1 is involved in the protective role of EDH against nitrative stress caused by excessive NO to maintain cardiac microvascular homeostasis.
A population ecology perspective on the functioning and future of health information organizations
Authors: Vest Joshua R. , Menachemi Nir
Published: November 2017

Background:

Increasingly, health care providers need to exchange information to meet policy expectations and business needs. A variety of health information organizations (HIOs) provide services to facilitate health information exchange (HIE). However, the future of these organizations is unclear.

Purpose:

The aim of this study was to explore the environmental context, potential futures, and survivability of community HIOs, enterprise HIEs, and electronic health record vendor-mediated exchange using the population ecology theory.

Approach:

Qualitative interviews with 33 key informants representing each type of HIE organization were analyzed using template analysis.

Results:

Community HIOs, enterprise HIEs, and electronic health record vendors exhibited a high degree of competition for resources, especially in the area of exchange infrastructure services. Competition resulted in closures in some areas. In response to environmental pressures, each organizational type was endeavoring to differentiate its services and unique use case, as well as pursing symbiotic relationships or attempting resource partitioning.

Conclusion:

HIOs compete for similar resources and are reacting to environmental pressures to better position themselves for continued survival and success. Our ecological research perspective helps move the discourse away from situation of a single exchange organization type toward a view of the broader dynamics and relationships of all organizations involved in facilitating HIE activities.

Practice Implications:

HIOs are attempting to partition the environment and differentiate services. HIE options should not be construed as an “either/or” decision, but one where multiple and complementary participation may be required.
CHARACTERISTICS OF PIGMENTED LESIONS IN TYPE 2 IDIOPATHIC MACULAR TELANGIECTASIA
Authors: Leung Irene , Sallo Ferenc B. , Bonelli Roberto , Clemons Traci E. , Pauleikhoff Daniel , Chew Emily Y. , Bird Alan C. , Peto Tunde ,   the MacTel Study Group
Published: November 2017

Purpose:

Pigment in the midretina is a characteristic sign in Type 2 idiopathic macular telangiectasia (MacTel) and is considered to characterize the late stage of the disease. Our aim was to investigate its incidence, and relationship with risk factors for MacTel, including outer retinal vascularization and subretinal neovascular proliferation (SRNV).

Methods:

Pigment extent was measured in fundus autofluorescence images of 150 eyes of 75 MacTel probands, using the Region Finder tool of Heidelberg Eye Explorer. A linear mixed model was used to analyze the dynamics of pigment and its associations with other features of the phenotype. The relative incidence of pigment and of outer retinal outer retinal vascularization and SRNV was analyzed within the full MacTel Study cohort (1,244 probands).

Results:

Mean pigment area at baseline was 0.157 mm2 (range = 0–1.295 mm2, SD = 0.228 mm2, n = 101). Progression demonstrated a nonlinear pattern (P < 0.001) at an overall rate of 0.0177 mm2/year and was associated with the initial plaque size and with SRNV. There was a strong correlation between fellow eyes (P ≤ 0.0001). In approximately 25% of all SRNV cases, SRNV may coincide with or precede pigment.

Conclusion:

Our data may be useful for refining the current system for staging disease severity in MacTel.
Impact of National Ten-Valent Pneumococcal Conjugate Vaccine Program on Reducing Antimicrobial Use and Tympanostomy Tube Placements in Finland
Authors: Palmu Arto A. , Rinta-Kokko Hanna , Nohynek Hanna , Nuorti J. Pekka , Jokinen Jukka
Published: October 2017

Background:

Otitis media in young children is associated with major resource use including antimicrobial consumption and tympanostomy tube placements (TTPs). We evaluated the impact of 10-valent pneumococcal conjugate vaccine (PCV10) introduction into the Finnish National Vaccination Programme (NVP) against these outcomes in vaccine-eligible children.

Methods:

PCV10-NVP began September 2010 with a 2 + 1 schedule; uptake in 2012 was estimated at 92%. The relative and absolute reduction in the NVP-eligible target cohort was compared with a season and age-matched (3–54 months) cohort before NVP introduction. Outpatient antimicrobial purchase data were collected from the Social Insurance Institution register. Data on purchases of antimicrobials recommended for treatment of acute otitis media by the Finnish Current Care Guidelines (amoxicillin with/without enzyme inhibitor, cefuroxime, cefaclor, clarithromycin, azithromycin) were collected, but full data on penicillin and sulfadiazine/trimethoprim were not available. Data on all TTP procedures were obtained from national hospital discharge register and Social Insurance Institution benefits register. Generalized Cox regression was used in the analysis.

Results:

The incidence rates of antimicrobial purchases in the reference and target cohorts were 1.09 and 0.89 per person-year, respectively. The relative rate reduction was 17.5% (95% confidence interval: 17.0–18.1) and the absolute rate reduction 0.20 per person-year. The rates of TTP in the reference and target cohorts were 5.41/100 and 4.56/100 person-years, respectively. The relative rate reduction was 14.8% (95% confidence interval: 13.1–16.5) and the absolute rate reduction 0.86/100 person-years.

Conclusions:

Use of antimicrobials and TTPs reduced after PCV10 was introduced into a routine vaccination program. This suggests considerable savings in health care resource use.
Quality Improvement Foley Project to Reduce Catheter-Related Trauma in a Large Community Hospital
Authors: Dave Chirag , Faraj Kassem , Vakharia Paras , Boura Judy , Hollander Jay
Published: November 2017

Indwelling catheter placement is a modifiable risk factor for urethral trauma. We implemented a multidisciplinary Foley Project protocol in June 2015, which consisted of a system-wide catheter education program, difficult urinary catheterization (DUC) algorithm, and skilled catheter nursing team to improve patient outcomes. A retrospective review of male DUC consults between June 2014 and September 2015 was performed. The preprotocol group includes consults received from June 2014 to May 2015. The postprotocol group includes consults received from June 2015 to September 2015. There were 74 patients in the preprotocol and 18 patients in the postprotocol group. The overall incidence rates of catheter-associated trauma during placement were 41.1% in the preprotocol and 5.9% in the postprotocol groups (p = .005). In the preprotocol group, 53.4% required a procedure by a urologist, whereas only 11.8% of patients in the postprotocol group required a procedure (p = .002). The Foley Project protocol reduced the frequency of catheter-associated trauma and procedures.
Association of Statins With Decreased Acute Pancreatitis Severity
Authors: Lee Peter J. , Modha Kunjam , Chua Tiffany , Chak Amitabh , Jang Daniel , Lopez Rocio , Gougol Amir , Papachristou Georgios I. , Stevens Tyler
Published: October 2017

Background:

Statins possess anti-inflammatory properties and have a protective effect in certain inflammatory conditions; however, their effect on the natural history of pancreatitis is unknown.

Aim:

The aim of this study is to assess the effect of statin exposure on the severity of pancreatitis and incidence of organ failure using a propensity-matched approach.

Methods:

A historical cohort study was conducted of adult patients with acute pancreatitis (AP) admitted in the Cleveland Clinic Health System between 2007 and 2014. All medication, clinical, and outcomes data were extracted from the electronic medical record. Factors that influence statin use were included in a propensity model to minimize selection bias. Patients on and off statins were matched (1:1) based on the propensity score to simulate a randomized controlled trial. Measured outcomes included pancreatitis severity (Revised Atlanta Classification), incidence of multisystem organ failure (MSOF), new MSOF, acute necrosis, and death. Additional surrogate markers of severity included hospital length of stay, Bedside Index of Severity of Acute Pancreatitis (BISAP), and presence of SIRS.

Results:

A total of 110 subjects taking a statin at admission were matched with 210 subjects not on a statin. Known baseline factors that may influence statin use and severity of pancreatitis were evenly matched between the 2 groups. Patients on a statin were less likely to develop MSOF, severe AP and necrosis. Although less in-hospital death occurred in the statin group when compared to nonusers, the difference was not statistically significant (2% vs. 4%; P=0.38).

Conclusions:

Statin use is associated with decreased severity of AP observed as reduction in both overall MSOF incidence and new MSOF. Prospective randomized controlled trials are needed to determine the efficacy of statin drugs in the treatment of AP.
Improved Identification of Venous Thromboembolism From Electronic Medical Records Using a Novel Information Extraction Software Platform
Authors: Dantes Raymund B. , Zheng Shuai , Lu James J. , Beckman Michele G. , Krishnaswamy Asha , Richardson Lisa C. , Chernetsky-Tejedor Sheri , Wang Fusheng
Published: October 2017

Introduction:

The United States federally mandated reporting of venous thromboembolism (VTE), defined by Agency for Healthcare Research & Quality Patient Safety Indicator 12 (AHRQ PSI-12), is based on administrative data, the accuracy of which has not been consistently demonstrated. We used IDEAL-X, a novel information extraction software system, to identify VTE from electronic medical records and evaluated its accuracy.

Methods:

Medical records for 13,248 patients admitted to an orthopedic specialty hospital from 2009 to 2014 were reviewed. Patient encounters were defined as a hospital admission where both surgery (of the spine, hip, or knee) and a radiology diagnostic study that could detect VTE was performed. Radiology reports were both manually reviewed by a physician and analyzed by IDEAL-X.

Results:

Among 2083 radiology reports, IDEAL-X correctly identified 176/181 VTE events, achieving a sensitivity of 97.2% [95% confidence interval (CI), 93.7%–99.1%] and specificity of 99.3% (95% CI, 98.9%–99.7%) when compared with manual review. Among 422 surgical encounters with diagnostic radiographic studies for VTE, IDEAL-X correctly identified 41 of 42 VTE events, achieving a sensitivity of 97.6% (95% CI, 87.4%–99.6%) and specificity of 99.8% (95% CI, 98.7%–100.0%). The performance surpassed that of AHRQ PSI-12, which had a sensitivity of 92.9% (95% CI, 80.5%–98.4%) and specificity of 92.9% (95% CI, 89.8%–95.3%), though only the difference in specificity was statistically significant (P<0.01).

Conclusion:

IDEAL-X, a novel information extraction software system, identified VTE from radiology reports with high accuracy, with specificity surpassing AHRQ PSI-12. IDEAL-X could potentially improve detection and surveillance of many medical conditions from free text of electronic medical records.