bluuebunny/crossref_metadata_2025_split huggingface dataset:
Joint effect of jamming and noise on the secrecy outage performance of wiretap channels with feedback delay and multiple antennas
Authors: Ortega Yosbel R. , Upadhyay Prabhat K. , da Costa Daniel Benevides , Bithas Petros S. , Kanatas Athanasios G. , Dias Ugo S. , de Sousa Junior Rafael Timoteo 
Published: May 2017

AbstractIn this paper, we investigate the secrecy performance of multiple‐input–multiple‐output wiretap channels with outdated channel state information (CSI) at the transmitter. The joint effect of multiple jamming signals and noise at the eavesdropper is studied assuming that the transmitter adopts a transmit antenna selection technique, while both the legitimate receiver and the eavesdropper use a maximal‐ratio combining scheme to achieve spatial diversity in reception. Exact closed‐form expressions for the nonzero secrecy rate probability and the secrecy outage probability for an arbitrary number of power distributed jamming signals are derived, by assuming both perfect and imperfect CSI. The general secrecy outage probability expressions are simplified for 2 special cases, ie, different and equal power distributed interferers. Furthermore, we conduct an asymptotic secrecy outage analysis at high signal‐to‐noise ratio, which reveals that the expected diversity gain cannot be realized for imperfect CSI and full diversity order can only be achieved under the perfect CSI condition. In addition, our results reveal that the number of antennas at the eavesdropper as well as the number of jamming signals do not affect the system diversity order. Simulation results are performed to illustrate the effects of imperfect feedback and other key system parameters on the secrecy performance. Finally, our analytical results are validated through Monte Carlo simulations.
Multiband chirp OCC‐UWB system design for suppression of multiple narrowband interferences
Authors: Bai Zhiquan , Gao Shen , Peng Shanshan , Dong Peihao , Yang Xinghai 
Published: May 2017

AbstractTo improve the coexistence between ultrawideband (UWB) technology–based wireless personal area networks and other narrowband systems and efficiently suppress the multiple narrowband interferences (NBIs) and the multiuser interference (MUI) in UWB systems, we propose a multiband orthogonal complementary code–based UWB (OCC‐UWB) system design in this paper, which utilizes the simple time‐frequency relationship of the chirp waveforms. The system design is implemented in 2 ways, named the equant multiband scheme and the nonequant multiband scheme. The 2 implementation schemes can improve the spectrum utilization of UWB systems and have different principles of NBI suppression. The equant scheme adopts the nonlinear chirp waveforms to suppress multiple NBIs in the subbands with NBIs. In contrast, the nonequant scheme adopts the spectrum elusion method based on the division of the frequency band to exclude the NBIs' frequency bands. Combining the chirp UWB pulse design with the orthogonal complementary code spread modulation, we finally present the multiband chirp OCC‐UWB system to suppress the MUI and the multipath interference simultaneously. Simulation results and theoretical analysis show that the proposed multiband chirp OCC‐UWB system improves the system performance efficiently in the conditions of multiple NBIs, MUI, and multipath interference and increases the data transmission rate and the spectrum utilization simultaneously.
Complex Strategic Choices: A New Approach and Application to Foreign Firm Agglomeration
Authors: Wu Zheying , Salomon Robert , Martin Xavier 
Published: May 2017

Research summaryIn this study, we introduce a new statistical technique to the field of strategy that accounts for complex interrelated decisions. The technique is meant for situations in which one strategic decision depends critically upon another—e.g., where companies must commit to one decision before making another. We demonstrate the value of the technique in the context of companies choosing countries in which to invest, followed by areas within those countries in which to locate their facilities. We then describe the generic benefits of the statistical technique, offer guidance for how to use it, and provide the programming code so that others can implement it. We explain how the technique is particularly well suited to problems in which companies must decide between multiple options and the sample size is small relative to the number of initial options.Managerial summaryResearch in strategy and international business has increasingly adopted two‐stage models to account for endogeneity. Established approaches, however, deal most effectively with problems characterized by binary first‐stage models. We introduce an alternative that allows for multiple choices in the first stage. We use the technique to examine the agglomeration patterns of foreign firms, while accounting for country selection. We find that, conditional on country selection, foreign firms tend to agglomerate in host countries characterized by collectivist cultures, political uncertainty, and economic uncertainty. The results imply that host country characteristics exert a strong influence on the agglomeration preferences of foreign firms. We provide guidance on when to use the empirical estimation technique and furnish details of the estimation procedure so that others can apply the technique to a broader class of selection problems. Copyright © 2017 Strategic Management Society.
R‐Ras deficiency does not affect papain‐induced IgE production in mice
Authors: Kummola Laura , Ortutay Zsuzsanna , Vähätupa Maria , Prince Stuart , Uusitalo‐Järvinen Hannele , Järvinen Tero A.H. , Junttila Ilkka S. 
Published: May 2017

AbstractIntroductionR‐Ras GTPase has recently been implicated in the regulation of immune functions, particularly in dendritic cell (DC) maturation, immune synapse formation, and subsequent T cell responses.MethodsHere, we investigated the role of R‐Ras in allergen‐induced immune response (type 2 immune response) in Rras deficient (R‐Ras KO) and wild type (WT) mice.ResultsInitially, we found that the number of conventional DC's in the lymph nodes (LNs) was reduced in R‐Ras KO mice. The expression of co‐stimulatory CD80 and CD86 molecules on these cells was also reduced on DC's from the R‐Ras KO mice. However, there was no difference in papain‐induced immune response between the R‐Ras WT and KO as measured by serum IgE levels after the immunization. Interestingly, neither the DC number nor co‐stimulatory molecule expression was different between WT and R‐Ras KO animals after the immunization.ConclusionsTaken together, despite having reduced number of conventional DC's in the R‐Ras KO mice and low expression of CD80 on DC's, the R‐Ras KO mice are capable of mounting papain‐induced IgE responses comparable to that of the WT mice. To our knowledge, this is the first report addressing potential differences in in vivo allergen responses regulated by the R‐Ras GTPase.
Visual comfort in autostereoscopic display
Authors: Chen Hung‐Shing , Wang Hsin‐Fu , Chou Ching‐Ju , Lin Tzung‐Han 
Published: May 2017

AbstractAutostereoscopic displays are likely to become widely used products in the future. However, certain physiological factors, especially visual comfort, limit their development. In this study, four observational parameters – ambient illuminance, image content, scaling ratio, and horizontal distance between major and minor objects – were evaluated to determine the degree of visual comfort offered by 3D computer‐generated images on an autostereoscopic display. Visual comfort score with the range of 0–1 is designed to represent the degree of visual comfort for the 3D images with different manipulations of ambient illuminance, image content, scaling ratio, and horizontal distance between major and minor objects in this study. Subjects were asked to indicate images that produced discomfort. The proportion of images for each condition where participants indicated that viewing the image was comfortable was computed. Images receiving a proportion of 0.5 or greater were classified as acceptable. The disparity ranges over which acceptable images were attained for each participant and for each condition were analyzed with analysis of variance. The analytical results indicate that ambient illuminance and image content have a significant effect on the acceptable disparity range, while scaling ratio and horizontal distance between major and minor objects did not.
Quantification of rat supraglottic laryngeal sensation threshold
Authors: Gale Derrick C. , Bhatt Neel K. , Paniello Randal C. 
Published: May 2017

ObjectiveLaryngeal adductor response (LAR) to air puff is used as a reliable method in evaluating sensation thresholds (ST) in human laryngeal sensory disorders. This method has been difficult to perform in small subjects such as rodents. The aims of this study were to 1) evaluate ST to air puff under binocular microlaryngoscopy in rats to evaluate laryngeal sensory disorders, 2) determine sensory thresholds at varying target locations, and 3) determine the ideal depth of anesthesia.Study DesignAnimal study.MethodsRats were induced with ketamine/xylazine. The level of anesthesia was monitored by spontaneous glottic closure and corneal reflex testing. Air puffs were delivered to the epiglottis, arytenoid, and piriform sinus at varied pressures with pulse time kept constant. Sensation thresholds were determined by direct visualization of the larynx using a binocular microscope. Topical lidocaine was then applied to the larynx and ST was determined. Trials were repeated in a small subset of animals.ResultsTwenty‐six trials were performed in 14 rats. Mean STs were 39 ± 9.7 mm Hg at the epiglottis, 48.8 ± 10.5 at the arytenoid, and not detectable at the pyriform sinus. Repeated trials demonstrated consistent results. Lidocaine effectively ablated the LAR in each trial. The LAR was difficult to induce while corneal reflex was absent and was difficult to distinguish from spontaneous glottic closures while under lighter sedation.ConclusionAir pulse stimulation in rats is a simple, reliable, and effective way to determine laryngopharyngeal STs in rats and can be used as an efficient and affordable method for experimentation involving laryngeal sensory disorders.Level of EvidenceNA. Laryngoscope, 127:E265–E269, 2017
Slotted labyrinthotomy approach with customized electrode for patients with common cavity deformity
Authors: Wei Xingmei , Li Yongxin , Fu Qian‐jie , Gong Yue , Chen Biao , Chen Jingyuan , Shi Ying , Su Qiaotong , Cui Danmo , Liu Ting 
Published: May 2017

Objectives/HypothesisCochlear implantation for patients with common cavity deformity (CCD) can be difficult, with a higher incidence of intra‐ and postoperative complications; outcomes with CCD patients are also highly variable. In this study, surgical time was compared between the traditional facial recess approach (TFRA) and the transmastoid slotted labyrinthotomy approach (TSLA). Audiological outcomes and the benefit of using customized electrode arrays for CCD patients are also discussed.Study DesignRetrospective review of 13 cochlear implant (CI) patients with CCD.MethodsSix patients were implanted with the TFRA using traditional electrodes, and seven patients were implanted with the TSLA using customized electrodes. Intra‐ and postoperative complications were reviewed. Audiological outcomes were measured 3 months to 2 years after CI activation.ResultsThe mean surgical time for TSLA group was nearly half as long as for the TRFA group (P < .05). Although mean audiological outcomes were better for the TSLA group, there was no significant difference between groups (P > .05).ConclusionsFor CCD patients, TSLA for cochlear implantation is recommended due to shortened surgical time; customized electrode arrays may be additionally advantageous in terms of audiological outcomes.Level of Evidence4. Laryngoscope, 128:468–472, 2018
High‐Quality Nano/Micro Hairy Single Crystals Developed from Poly(3‐hexylthiophene)‐Based Conductive–Dielectric Block Copolymers Having Flat‐on and Edge‐on Orientations
Authors: Zenoozi Sahar , Agbolaghi Samira , Gheybi Homa , Abbasi Farhang 
Published: May 2017

Highly uniform and conductive single crystals of poly(3‐hexylthiophene) (P3HT)‐based homo and block copolymers with the end coily blocks of polystyrene, poly(methyl methacrylate), and poly(ethylene glycol) are developed using self‐seeding method from varied quality solvents. Edge‐on and flat‐on orientations are detected depending on the thickness and width of single crystals. Coily blocks are excluded from the P3HT crystalline structures, leading to brush‐like or hairy regions on surface of grown single crystals in the longitude of P3HT chains. The larger single crystals possessing flat‐on orientation are obtained from weaker solvents at higher seeding temperatures. The longer P3HT chains are folded, however, the shorter backbones are laminated on each other. The highest backbone lamination occurs for homo‐P3HT7150 (Mn of P3HT = 7150 g mol−1) single crystals grown at 20 °C from anisole, the weakest employed solvent. In contract, highly ordered and folded hairy single crystals are acquired from better solvents and high molecular weight P3HTs. In these conditions, the crystallographic features of the hairy block copolymer single crystals are similar to those of nonhairy homo‐P3HT ones. The coily brush‐covered P3HT48 800 single crystals have more foldings compared to the homo‐P3HT48 800 ones, whereas only two laminated backbones in shorter P3HT blocks are detected.
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Negative correlation between serum uric acid and kidney URAT1 mRNA expression caused by resveratrol in rats
Authors: Lee Cheng‐Tse , Chang Li‐Ching , Liu Ching‐Wen , Wu Pei‐Fung 
Published: May 2017

ScopeThis study established a hyperuricemic rat model to elucidate the effect of resveratrol on the transport of UA in the kidney.Methods and resultsHyperuricemia was induced in rats through daily oral gavage of a potassium oxonate and UA mixture over 3 weeks. Our results revealed that resveratrol significantly reduced the serum UA levels but not creatinine, c‐creative protein, alanine aminotransferase, or aspartate aminotransferase levels in these rats. Furthermore, renal URAT1 and OAT1 mRNA expression were significantly higher in the rats treated with allopurinol than in those with no treatment. Therefore, allopurinol not only inhibited UA production but also mediated renal URAT1 and OAT1 expression. The correlation analysis revealed that UA levels correlated negatively with renal IL‐6 mRNA expression in rats treated with allopurinol. Moreover, URAT1 showed strong immunoreactivity in the distal convoluted tubule of rats treated with allopurinol or resveratrol and in hyperuricemic treated with allopurinol. Finally, in the rats treated with resveratrol, UA levels correlated negatively with renal URAT1 mRNA expression; thus, resveratrol reduced URAT1 mRNA expression under high UA levels, thereby reducing UA reabsorption in renal cells.ConclusionResveratrol contributes to URAT1 expression, which is potentially useful in therapeutic strategies aimed at treating hyperuricemia.
Predicting the initiation of static liquefaction of cross‐anisotropic sands under multiaxial stress conditions
Authors: Lü Xilin , Huang Maosong , Andrade José E. 
Published: May 2017

SummaryExperimental evidence has shown that the liquefaction instability of sands can be affected by its material density, stress state, and inherent anisotropy. In order to predict the initiation of the static liquefaction of inherent cross‐anisotropic sands under multidimensional stress conditions, a rational constitutive model is needed. An elastoplasticity model able to capture the influences of intermediate principal stress ratio (b = (σ2 − σ3)/(σ1 − σ3)) and loading direction on stress–strain relationships and volumetric properties was proposed. The yield function was formulated to be controlled by Lode angle, loading direction, and material state; the stress–dilatancy was a material state‐dependent function. After using the existing drained hollow cylinder tests to validate the proposed model, this model was used to simulate the existing undrained hollow cylinder tests. During this simulation, the second‐order work criterion was used to determine the initiation of static liquefaction. The results showed that an increase in both the intermediate principal stress ratio and the loading angle induces a decrease in the second‐order work. Static liquefaction is initiated more easily at a stress state with a large intermediate principal stress ratio and a large loading angle, and the mobilized friction angle at the instability points decreases with the intermediate principal stress ratio and the loading angle. Copyright © 2017 John Wiley & Sons, Ltd.
Recent research on composite beams with demountable shear connectors
Authors: Lam Dennis , Dai Xianghe , Ashour Ashraf , Rehman Naveed 
Published: May 2017

AbstractThis paper presents the experimental and numerical investigations of an innovative composite floor system with deconstructability. In this system, a composite slab formed with metal profiled decking is connected to a steel beam using demountable shear connectors. A series of push tests was conducted to investigate the behaviour of this form of shear connector. In addition to the push tests, a full‐scale composite beam was tested to failure in the laboratory under a number of cycles of monotonic loading. For direct comparison, a similar composite beam test was conducted using the same section size and concrete strength, but using conventional welded headed stud connectors. Test results showed that the behaviour of the composite beam with demountable shear connectors is comparable with that of the specimen with welded shear connectors. After the test was terminated, the demountable shear connectors were unfastened and the composite floor could be easily lifted off from the steel beam. Test results showed that these demountable shear connectors possess high ductility in comparison to the equivalent welded shear connectors. Simple design rules currently use in Eurocode 4 for welded shear connections and Eurocode 3 for bolts are proposed to predict the shear resistance of this form of demountable shear connector.
Hemipelvectomy with laparoscopic abdominoperineal excision for epithelioid sarcoma treatment
Authors: Santana Daniel Paulino , Estrada Meyer Matheus Matta Machado Mafra Duque , Santos Edmilson Celso , Andrade Camila Gomes de Souza , Vilela Neto Paulo , Matoso Aline Alves , Santos Bruna Sílvia Torres , Silva Bruno José Guedes , Ferreira Danielle Bossi Grassi , Horta Larissa Vasconcelos , Reis Marcos Campos Wanderley 
Published: May 2017

AbstractThe epithelioid sarcoma (ES) is an unusual variant of the sarcoma, not reaching 1% of all soft tissue sarcomas. Initially reported in 1970, it has a more aggressive variant, which was classified as the “proximal-type” in 1997. These are aggressive tumors with high rates of distant metastasis and local relapses. Isolated radio and chemotherapy responses are poor and free-margin surgical resection is the treatment of choice.This is the case report of a 25-year-old male patient diagnosed with “proximal-type” ES in the perineal region. He underwent surgical resection in another institution and was later admitted to our institution with local recurrence with rectal and left thigh muscle invasion. Neoadjuvant radio-chemotherapy was performed, followed by laparoscopic abdominoperineal rectal resection and partial left hemipelvectomy associated with left lower-limb amputation. The patient had no postoperative complications and is currently undergoing outpatient follow-up. The anatomopathological analysis showed tumor-free margins.The “proximal-type” ES is a rare soft-tissue sarcoma subtype. High local recurrence, as well as the metastasis rates, makes its treatment a challenging task.
Incidence and predictors of pericardial effusion as an early complication of catheter ablation for atrial fibrillation: The Japanese Catheter Ablation Registry of Atrial Fibrillation (J‐CARAF)
Authors: Murakawa Yuji , Yamane Teiichi , Goya Masahiko , Inoue Koichi , Naito Shigeto , Kumagai Koichiro , Miyauchi Yasushi , Morita Norishige , Nogami Akihiko , Shoda Morio , Okumura Ken , Hirao Kenzo ,   on behalf of the Japanese Heart Rhythm Society Members
Published: May 2017

AbstractBackgroundPericardial effusion (PE) is one of the most frequent complications from catheter ablation of atrial fibrillation (AF). We assessed the prevalence and predictive factors of PE that require invasive treatment as an early complication of AF ablation.MethodsThe Japanese Heart Rhythm Society requested electrophysiology centers to register the relevant data of patients who underwent AF ablation during 6 months from 2011 to 2015. We compared the clinical profiles and the procedures of AF ablation between patients who had ablation‐related PE and those who did not.ResultsTwo‐hundred‐and‐eight institutions reported the data of 8319 AF ablation sessions (age 63.4±10.7 years). A total of 414 complications occurred in 401 patients (4.8%). The incidence of invasively treated critical PE was 1.0% (n=85) of total procedures, while conservatively treated noncritical PE appeared in 95 subjects. When clinical and procedural variables were compared between patients who suffered critical PE and 8140 PE‐free patients, deep sedation (p=0.030), impaired left ventricular function (p=0.031), and periprocedural warfarin (p=0.023) significantly increased the incidence of critical PE in univariate analysis. Use of 3‐D imaging system (p<0.001) and a periprocedural direct oral anticoagulant (DOAC, p=0.002) were related with lower incidence of critical PE. Among these factors, multivariate logistic regression analysis showed that 3‐D imaging system (odds ratio 0.23 [95% CI: 0.14–0.39], p<0.001) and a periprocedural DOAC (odds ratio 0.49 [95% CI: 0.27–0.90], p=0.020) are independent predictors of the lower incidence of PE.ConclusionsCritical PE occurred in 1% of AF ablation procedures in Japan. Our results suggest that 3‐D imaging system use independently reduces the frequency of PE. DOACs in the setting of catheter ablation of AF seemed to be non‐inferior to warfarin in terms of safety and effectiveness.
Antimicrobial resistance in human populations: challenges and opportunities
Authors: Allcock S. , Young E. H. , Holmes M. , Gurdasani D. , Dougan G. , Sandhu M. S. , Solomon L. , Török M. E. 
Published: May 2017

AbstractAntimicrobial resistance (AMR) is a global public health threat. Emergence of AMR occurs naturally, but can also be selected for by antimicrobial exposure in clinical and veterinary medicine. Despite growing worldwide attention to AMR, there are substantial limitations in our understanding of the burden, distribution and determinants of AMR at the population level. We highlight the importance of population-based approaches to assess the association between antimicrobial use and AMR in humans and animals. Such approaches are needed to improve our understanding of the development and spread of AMR in order to inform strategies for the prevention, detection and management of AMR, and to support the sustainable use of antimicrobials in healthcare.