bluuebunny/crossref_metadata_2025 huggingface dataset:
A 3D-Printed Hybrid Water Antenna with Tunable Frequency and Beamwidth
Authors: Zhong Zeng-Pei , Liang Jia-Jun , Huang Guan-Long , Yuan Tao
Published: October 2018

A novel hybrid water antenna with tunable frequency and beamwidth is proposed. An L-shaped metallic strip is adopted as the feeding structure of the antenna in order to effectively broaden the operating bandwidth. The L-shaped strip feeder and a rectangular water dielectric resonator constitute the driven element. Five identical rectangular water dielectric elements are mounted linearly with respect to the driven element, which act as the directors and contribute to narrow the beamwidth. By varying the height of the liquid water level in the driven element, the proposed antenna is able to tune to different operational frequencies. Furthermore, it is also able to adjust to different beamwidths and gains via varying the number of director elements. A prototype is fabricated by using 3-D printing technology, where the main parts of the antenna are printed with photopolymer resin, and then the ground plane and L-shaped strip feeder are realized by using adhesive copper tapes. Measurement results agree well the simulation ones. A tunable frequency ranging from 4.66 GHz to 5.65 GHz is obtained and a beam steering along a fixed direction with a gain variation less than 0.5 dB is realized.
Analyzing of a Photovoltaic/Wind/Biogas/Pumped-Hydro Off-Grid Hybrid System for Rural Electrification in Sub-Saharan Africa—Case Study of Djoundé in Northern Cameroon
Authors: Yimen Nasser , Hamandjoda Oumarou , Meva’a Lucien , Ndzana Benoit , Nganhou Jean
Published: October 2018

Traditional electrification methods, including grid extension and stand-alone diesel generators, have shown limitations to sustainability in the face of rural electrification challenges in sub-Saharan Africa (SSA), where electrification rates remain the lowest in the world. This study aims at performing a techno-economic analysis and optimization of a pumped-hydro energy storage based 100%-renewable off-grid hybrid energy system for the electrification of Djoundé, which is a small village in northern Cameroon. Hybrid Optimization of Multiple Energy Resources (HOMER) software was used as an analysis tool, and the resulting optimal system architecture included an 81.8 kW PV array and a 15 kW biogas generator, with a cost of energy (COE) and total net present cost (NPC) of €0.256/kWh and €370,426, respectively. The system showed promise given the upcoming decrease in installation cost of photovoltaic systems. It will be viable in parts of SSA region but, significant investment subsidies will be needed elsewhere. The originality of this study can be emphasized in three points: (1) the modelling with the recently introduced pumped-hydro component of HOMER; (2) broadening sensitivity analysis applications to address practical issues related to hybrid renewable energy systems (HRES); and, (3) consideration of the agricultural sector and seasonal variation in the assessment of the electricity demand in an area of SSA.
FPGA-Based Real-Time Digital Solver for Electro-Mechanical Transient Simulation
Authors: Zhang Bingda , Wang Yang , Tu Sijia , Jin Zhao
Published: October 2018

A field-programmable gate array (FPGA)-based digital solver for real-time electromechanical transient simulation is designed in this paper. The solving process for a device or sub-network in an electromechanical transient simulation is packaged into the orders in soft function solvers. The orders are reused by soft function solvers that are invoked by microprocessor cores. The data exchange between the microprocessor cores and soft function solvers is enhanced through explicit and implicit channels. The orders of the microprocessor cores are stored in the synchronous dynamic random access memory on the FPGA board, which solves the problem of insufficient storage space for the orders in electromechanical transient simulation. A real-time digital solver for electromechanical transient simulation, whose feasibility is verified by a simulation of part of the power system in East China, is successfully constructed by applying a small number of microprocessor cores and multiple soft function solvers.
Numerical Study of the Axial Gap and Hot Streak Effects on Thermal and Flow Characteristics in Two-Stage High Pressure Gas Turbine
Authors: Choi Myung Gon , Ryu Jaiyoung
Published: October 2018

Combined cycle power plants (CCPPs) are becoming more important as the global demand for electrical power increases. The power and efficiency of CCPPs are directly affected by the performance and thermal efficiency of the gas turbines. This study is the first unsteady numerical study that comprehensively considers axial gap (AG) in the first-stage stator and first-stage rotor (R1) and hot streaks in the combustor outlet throughout an entire two-stage turbine, as these factors affect the aerodynamic performance of the turbine. To resolve the three-dimensional unsteady-state compressible flow, an unsteady Reynolds-averaged Navier–Stokes (RANS) equation was used to calculate a k − ω   SST   γ turbulence model. The AG distance d was set as 80% (case 1) and 120% (case 3) for the design value case 2 (13 mm or d/Cs1 = 0.307) in a GE-E3 gas turbine model. Changes in the AG affect the overall flow field characteristics and efficiency. If AG decreases, the time-averaged maximum temperature and pressure of R1 exhibit differences of approximately 3 K and 400 Pa, respectively. In addition, the low-temperature zone around the hub and tip regions of R1 and second-stage rotor (R2) on the suction side becomes smaller owing to a secondary flow and the area-averaged surface temperature increases. The area-averaged heat flux of the blade surface increases by a maximum of 10.6% at the second-stage stator and 2.8% at R2 as the AG decreases. The total-to-total efficiencies of the overall turbine increase by 0.306% and 0.295% when the AG decreases.
The Effect of Customer Participation Types on Online Recovery Satisfaction: A Mental Accounting Perspective
Authors: Zhang Yu , Shao Bingjia
Published: October 2018

With the high popularity of the Internet, online trading has gradually replaced the traditional shopping model and extended to every corner of social life. However, online trading cannot avoid failures; thus, understanding how firms can best recover customers in online contexts to keep customer loyalty is very important. This study investigates the mechanisms by which customer participation types (physical, mental, and emotional) promote customers’ perceived justice and post-recovery satisfaction from a mental accounting perspective. Furthermore, the moderating effects of two modes of online apology speech acts (direct and indirect) on customer participation and perceived justice are investigated. A total of 1083 Chinese tourists who have purchased a Wi-Fi rental service in the past year were contacted according to the database provided by two travel agencies, and 329 stated having experienced an online recovery service and participated in the survey; 297 valid questionnaires were collected. Among them, 48.82% were males and 51.18% females. Most of the respondents were aged 20–35 years. By carrying out data analysis by partial least squares structural equation modeling (PLS-SEM) using SmartPLS, the results show that, first, only mental and physical participation can enhance perceived justice, while emotional participation does not influence perceived justice. Second, the positive influence of mental participation on perceived justice is most significant. Third, only when the service staff adopts the indirect mode to express an online apology, mental and physical participation can enhance perceived justice.
Structured Data REST Protocol for End to End Data Mashup
Authors: Hardaha Prakash , Singh Shailendra
Published: October 2018

Due to the exponential growth of the data and its services, visiting multiple webs/apps by a user raises three issues—(1) consumption of extra bytes; (2) time killing process of surfing inside the webs/apps; (3) tedious task of remembering address of webs/apps with their credentials. The data mashup is a set of techniques and user-friendly approaches which not only resolves above issues but also allows ordinary user to fetch required data from multiple disparate data sources and to create the integrated view in his defined digital place. In this paper, we have proposed an extension of existing REST protocol called Structured Data REST (SDRest) protocol and user-friendly novel approach which allows even ordinary users to develop end to end data mashup, using the innovative concept of Structured Data Mashup Box (SDMB) and One Time Configuration (OTC)-Any Time Access (ATA) models. Our implementation shows that pre-mashup configuration can easily be performed by an ordinary user and an integrated user interface view of end user data mashup can be created without any technical knowledge or programming. We have also evaluated the proposed work by comparing it with some of the related works and found that the proposed work has developed user friendly configurable approach using the current state of the art techniques to involve not only the ordinary user but also the mashup service provider and the data service provider to develop public, private and hybrid data mashup.
An Experimental Study of Pulsatile Flow in a Compliant Aortic Root Model under Varied Cardiac Outputs
Authors: Zhang Ruihang , Zhang Yan
Published: October 2018

The fluid dynamics of a natural aortic valve are complicated due to the highly pulsatile flow conditions, the compliant wall boundaries, and the sophisticated geometry of the aortic root. In the present study, a pulsatile flow simulator was constructed and utilized to investigate the turbulent characteristics and structural deformation of an intact silicone aortic root model under different flow inputs. Particle image velocimetry and high-frequency pressure sensors were combined to gather the pulsatile flow field information. The results demonstrated the distributions and the variations of the jet flow structures at different phases of a cardiac cycle. High turbulence kinetic energy was observed after the peak systole phase when the flow started to decelerate. Deformations of the aortic root upstream and downstream of the valve leaflets under normal boundary conditions were summarized and found to be comparable to results from clinical studies. The cardiac output plays an important role in determining the strength of hemodynamic and structural responses. A reduction in cardiac outputs resulted in a lower post-systole turbulence, smaller circumferential deformation, a smaller geometric orifice area, and a shortened valve-opening period.
Investigation of Similarity in the Spectra between Short- and Long-Duration Gamma-ray Bursts
Authors: Sakamoto Takanori , Yoshida Yuuki , Serino Motoko
Published: October 2018

We investigated the spectral properties of the prompt emission for short- and long-duration gamma-ray bursts (GRBs) using the Fermi Gamma-ray Burst Monitor data. In particular, we focused on comparing the spectral properties of short GRBs and the initial 2 s of long GRBs, motivated by the previous study of Ghirlanda et al. (2009). We confirmed the similarity in the low energy photon index α between short GRBs and the initial 2 s of long GRBs. Since about a quarter of our spectra of both short GRBs and the initial 2 s of long GRBs show α to be shallower than - 2 / 3 , it is difficult to understand in the context standard synchrotron emission.
Genotype Fingerprints Enable Fast and Private Comparison of Genetic Testing Results for Research and Direct-to-Consumer Applications
Authors: Robinson Max , Glusman Gustavo
Published: October 2018

Genetic testing has expanded out of the research laboratory into medical practice and the direct-to-consumer market. Rapid analysis of the resulting genotype data now has a significant impact. We present a method for summarizing personal genotypes as ‘genotype fingerprints’ that meets these needs. Genotype fingerprints can be derived from any single nucleotide polymorphism-based assay, and remain comparable as chip designs evolve to higher marker densities. We demonstrate that these fingerprints support distinguishing types of relationships among closely related individuals and closely related individuals from individuals from the same background population, as well as high-throughput identification of identical genotypes, individuals in known background populations, and de novo separation of subpopulations within a large cohort through extremely rapid comparisons. Although fingerprints do not preserve anonymity, they provide a useful degree of privacy by summarizing a genotype while preventing reconstruction of individual marker states. Genotype fingerprints are therefore well-suited as a format for public aggregation of genetic information to support ancestry and relatedness determination without revealing personal health risk status.
Dysphagia Onset in Older Adults during Unrelated Hospital Admission: Quantitative Videofluoroscopic Measures
Authors: Jardine Marie , Miles Anna , Allen Jacqui
Published: October 2018

New-onset swallowing difficulties in older patients during unrelated hospital admissions are well recognized and may result in prolonged hospital stay and increased morbidity. Presbyphagia denotes age-related swallowing changes which do not necessarily result in pathological effects. The trajectory from presbyphagia to dysphagia is not well understood. This retrospective observational study compared quantitative videofluoroscopic measures in hospitalized older adults aged 70–100 years, reporting new dysphagia symptoms during admission (n = 52), to healthy asymptomatic older (n = 56) and younger adults (n = 43). Significant physiological differences seen in hospitalized older adults but not healthy adults, were elevated pharyngeal area (p < 0.001) and pharyngeal constriction ratio (p < 0.001). Significantly increased penetration (p < 0.001), aspiration (p < 0.001) and pharyngeal residue (p < 0.001) were also observed in the hospitalized older cohort. Reasons for onset of new swallow problems during hospitalization are likely multifactorial and complex. Alongside multimorbidity and polypharmacy, a combination of factors during hospitalization, such as fatigue, low levels of alertness, delirium, reduced respiratory support and disuse atrophy, may tip the balance of age-related swallowing adaptations and compensation toward dysfunctional swallowing. To optimize swallowing assessment and management for our aging population, care must be taken not to oversimplify dysphagia complaints as a characteristic of aging.
In the Traces of Modernism: William Faulkner in Swedish Criticism 1932–1950
Authors: Jansson Mats
Published: October 2018

This article focusses the reception of William Faulkner in Sweden from the first introduction in 1932 until the Nobel Prize announcement in 1950. Through reviews, introductory articles, book chapters, forewords, and translations, the critical evaluation of Faulkner’s particular brand of modernism is traced and analyzed. The analysis takes theoretical support from Hans Robert Jauss’ notion of ‘horizon of expectations’, Gérard Genette’s concept of ‘paratext’, and E.D. Hirsh’s distinction between ‘meaning’ and ‘significance’. To pinpoint the biographical and psychologizing tendency in Swedish criticism, Roland Barthes’s notion of ‘biographeme’ is introduced. The analysis furthermore shows that the critical discussion of Faulkner’s modernism could be ordered along an axis where the basic parameters are form and content, aesthetics and ideology, narrator and author, and writer and reader. The problematics adhering to these fundamental aspects are more or less relevant for the modernist novel in general. Thus, it could be argued that the reception of Faulkner in Sweden and Swedish Faulkner criticism epitomize and highlight the fundamental features pertaining to the notion of ‘modernism’, both with regard to its formal and content-based characteristics.
Environmental Electronic Vape Exposure from Four Different Generations of Electronic Cigarettes: Airborne Particulate Matter Levels
Authors: Protano Carmela , Avino Pasquale , Manigrasso Maurizio , Vivaldi Valerio , Perna Franco , Valeriani Federica , Vitali Matteo
Published: October 2018

Electronic cigarettes (e-cigs) were introduced into the market in 2006 and their technological features have evolved substantially over time. Currently, there are four different generations of e-cigs that are broadly considered less harmful than the use of combusted tobacco products although passive exposure to aerosols often occurs in public spaces and indoor environments. The study aim was to evaluate the levels of airborne particulate matter (PM) emitted during the use of all the four generations of e-cigs, testing different use modalities. PM10, PM4, PM2.5 and PM1 were measured through a Dusttrak ™ II Aerosol Monitor, for a total of 20 independent experiments. All tested e-cigs devices produced PM during their use, and PM10 was almost made of PM1 size fraction. In addition, we observed a progressive increase in PM emission from the first to the fourth generation, and an upward trend of PM1 emitted by the fourth generation e-cig with an increase in the operating power. The results showed that, whatever the model adopted, passive vaping does occur. This finding supports the need for legislative interventions to regulate the e-cigs use in public places and other enclosed environments, in order to protect the health of any subject who is potentially exposed.
Analysis of Heavy Metal Sources in the Soil of Riverbanks Across an Urbanization Gradient
Authors: Zuo Shudi , Dai Shaoqing , Li Yaying , Tang Jianfeng , Ren Yin
Published: October 2018

Regional soil quality issues arising from rapid urbanization have received extensive attention. The riverbank that runs through a city is representative of urbanization gradient transformation. Thirty soil samples in the Yangtze River Delta urban agglomeration were collected and analyzed for the concentrations of seven analytes. Correlation, principle component analysis, cluster analysis and GeoDetector models suggested that the four groups (Cr-Ni-Cu, Cu-Zn-As-Sb, Cd and Pb) shared the same sources in the core urban region; five groups (Cr-Ni-Cu-Zn, As, Cd, Sb and Pb) in the suburbs and three groups (Cr-Ni, Cu-Zn-Cd-Sb-Pb and As) in the exurbs. GeoDetector methods not only validated the results of the three other methods, but also provided more possible impact factors. Besides the direct influences, the interaction effects among factors were quantified. Interactive combination with strong nonlinear increment changed from between-two-weak factors in the central region to between-strong-and-weak factors in the suburbs. In the exurbs, the stronger interaction effects were observed between strong and weak factors. Therefore, the GeoDetector model, which provided more detailed information of artificial sources could be used as a tool for identifying the potential factors of toxic elements and offering scientific basis for the development of subsequent pollution reduction strategies.
Non-Canonical Regulation of Type I Collagen through Promoter Binding of SOX2 and Its Contribution to Ameliorating Pulmonary Fibrosis by Butylidenephthalide
Authors: Chuang Hong-Meng , Ho Li-Ing , Huang Mao-Hsuan , Huang Kun-Lun , Chiou Tzyy-Wen , Lin Shinn-Zong , Su Hong-Lin , Harn Horng-Jyh
Published: October 2018

Pulmonary fibrosis is a fatal respiratory disease that gradually leads to dyspnea, mainly accompanied by excessive collagen production in the fibroblast and myofibroblast through mechanisms such as abnormal alveolar epithelial cells remodeling and stimulation of the extracellular matrix (ECM). Our results show that a small molecule, butylidenephthalide (BP), reduces type I collagen (COL1) expression in Transforming Growth Factor beta (TGF-β)-induced lung fibroblast without altering downstream pathways of TGF-β, such as Smad phosphorylation. Treatment of BP also reduces the expression of transcription factor Sex Determining Region Y-box 2 (SOX2), and the ectopic expression of SOX2 overcomes the inhibitory actions of BP on COL1 expression. We also found that serial deletion of the SOX2 binding site on 3′COL1 promoter results in a marked reduction in luciferase activity. Moreover, chromatin immunoprecipitation, which was found on the SOX2 binding site of the COL1 promoter, decreases in BP-treated cells. In an in vivo study using a bleomycin-induced pulmonary fibrosis C57BL/6 mice model, mice treated with BP displayed reduced lung fibrosis and collagen deposition, recovering in their pulmonary ventilation function. The reduction of SOX2 expression in BP-treated lung tissues is consistent with our findings in the fibroblast. This is the first report that reveals a non-canonical regulation of COL1 promoter via SOX2 binding, and contributes to the amelioration of pulmonary fibrosis by BP treatment.
Chaperones, Canalization, and Evolution of Animal Forms
Authors: Sato Atsuko
Published: October 2018

Over half a century ago, British developmental biologist Conrad Hal Waddington proposed the idea of canalization, that is, homeostasis in development. Since the breakthrough that was made by Rutherford and Lindquist (1998), who proposed a role of Hsp90 in developmental buffering, chaperones have gained much attention in the study of canalization. However, recent studies have revealed that a number of other molecules are also potentially involved in canalization. Here, I introduce the emerging role of DnaJ chaperones in canalization. I also discuss how the expression levels of such buffering molecules can be altered, thereby altering organismal development. Since developmental robustness is maternally inherited in various organisms, I propose that dynamic bet hedging, an increase in within-clutch variation in offspring phenotypes that is caused by unpredictable environmental challenges to the mothers, plays a key role in altering the expression levels of buffering molecules. Investigating dynamic bet hedging at the molecular level and how it impacts upon morphological phenotypes will help our understanding of the molecular mechanisms of canalization and evolutionary processes.
Novel Functions of Death-Associated Protein Kinases through Mitogen-Activated Protein Kinase-Related Signals
Authors: Elbadawy Mohamed , Usui Tatsuya , Yamawaki Hideyuki , Sasaki Kazuaki
Published: October 2018

Death associated protein kinase (DAPK) is a calcium/calmodulin-regulated serine/threonine kinase; its main function is to regulate cell death. DAPK family proteins consist of DAPK1, DAPK2, DAPK3, DAPK-related apoptosis-inducing protein kinases (DRAK)-1 and DRAK-2. In this review, we discuss the roles and regulatory mechanisms of DAPK family members and their relevance to diseases. Furthermore, a special focus is given to several reports describing cross-talks between DAPKs and mitogen-activated protein kinases (MAPK) family members in various pathologies. We also discuss small molecule inhibitors of DAPKs and their potential as therapeutic targets against human diseases.
Dynamic Handwriting Analysis for Supporting Earlier Parkinson’s Disease Diagnosis
Authors: Impedovo Donato , Pirlo Giuseppe , Vessio Gennaro
Published: October 2018

Machine learning techniques are tailored to build intelligent systems to support clinicians at the point of care. In particular, they can complement standard clinical evaluations for the assessment of early signs and manifestations of Parkinson’s disease (PD). Patients suffering from PD typically exhibit impairments of previously learned motor skills, such as handwriting. Therefore, handwriting can be considered a powerful marker to develop automatized diagnostic tools. In this paper, we investigated if and to which extent dynamic features of the handwriting process can support PD diagnosis at earlier stages. To this end, a subset of the publicly available PaHaW dataset has been used, including those patients showing only early to mild degree of disease severity. We developed a classification framework based on different classifiers and an ensemble scheme. Some encouraging results have been obtained; in particular, good specificity performances have been observed. This indicates that a handwriting-based decision support tool could be used to administer screening tests useful for ruling in disease.
Fetal Renal Echogenicity Associated with Maternal Focal Segmental Glomerulosclerosis: The Effect of Transplacental Transmission of Permeability Factor suPAR
Authors: Shuster Shirley , Ankawi Ghada , Licht Christoph , Reiser Jochen , Wang Xuexiang , Wei Changli , Chitayat David , Hladunewich Michelle
Published: October 2018

We report a case of a pregnant woman with nephrotic syndrome due to biopsy-proven focal segmental glomerulosclerosis (FSGS) whose fetus developed echogenic kidneys and severe oligohydramnios by 27 weeks of gestation. Maternal treatment with prednisone resulted in normalization of the amniotic fluid indices and resolution of fetal renal echogenicity. The newborn was noted to have transient renal dysfunction and proteinuria, resolving by 6 weeks postpartum. The transplacental passage of permeability factors is postulated to have caused both the fetal and newborn renal presentation, with significantly elevated levels of soluble urokinase-type plasminogen activator receptor (suPAR) noted in the cord blood. This case documents the transplacental maternal-fetal transmission of suPAR, demonstrating the potential for maternal-fetal transmission of deleterious, disease-causing entities, and adds to the differential diagnosis of fetal echogenic kidneys. Further, this is the first documentation of a fetal response to maternal systemic therapy.
Current and Emerging Reconstituted HDL-apoA-I and HDL-apoE Approaches to Treat Atherosclerosis
Authors: Valanti Eftaxia-Konstantina , Dalakoura-Karagkouni Katerina , Sanoudou Despina
Published: October 2018

Atherosclerosis affects millions of people worldwide. However, the wide variety of limitations in the current therapeutic options leaves much to be desired in future lipid-lowering therapies. For example, although statins, which are the first-line treatment for coronary heart disease (CHD), reduce the risk of cardiovascular events in a large percentage of patients, they lead to optimal levels of low density lipoprotein-cholesterol (LDL-C) in only about one-third of patients. A new promising research direction against atherosclerosis aims to improve lipoprotein metabolism. Novel therapeutic approaches are being developed to increase the levels of functional high density lipoprotein (HDL) particles. This review aims to highlight the atheroprotective potential of the in vitro synthesized reconstituted HDL particles containing apolipoprotein E (apoE) as their sole apolipoprotein component (rHDL-apoE). For this purpose, we provide: (1) a summary of the atheroprotective properties of native plasma HDL and its apolipoprotein components, apolipoprotein A-I (apoA-I) and apoE; (2) an overview of the anti-atherogenic functions of rHDL-apoA-I and apoA-I-containing HDL, i.e., natural HDL isolated from transgenic Apoa1−/− × Apoe−/− mice overexpressing human apoA-I (HDL-apoA-I); and (3) the latest developments and therapeutic potential of HDL-apoE and rHDL-apoE. Novel rHDL formulations containing apoE could possibly present enhanced biological functions, leading to improved therapeutic efficacy against atherosclerosis.
Applications of Electrochromic Copolymers Based on Tris(4-carbazoyl-9-ylphenyl)amine and Bithiophene Derivatives in Electrochromic Devices
Authors: Kuo Chung-Wen , Chang Jui-Cheng , Lee Po-Ying , Wu Tzi-Yi , Huang Yu-Chang
Published: October 2018

Four copolymers (P(tCz (tris(4-carbazoyl-9-ylphenyl)amine)-co-bTP (2,2′-bithiophene)), P(tCz-co-CPDT (4H-cyclopenta[2,1-b:3,4-b’]dithiophene)), P(tCz-co-DTC (3,6-di(2-thienyl)carbazole)), and P(tCz-co-CPDTK (cyclopentadithiophene ketone))) are deposited on indium tin oxide (ITO) surfaces using electrochemical polymerization. Spectroelectrochemical properties of copolymer electrodes reveal that the colors of P(tCz-co-bTP) film are pinkish-orange, light olive green, light grayish blue, and dark blue at 0.0, 0.8, 1.2, and 1.6 V, respectively, whereas the color variations of P(tCz-co-CPDTK) film are light yellow, yellow, and blue at 0.0 V, 0.8 V, and 1.5 V, respectively. The ΔT of P(tCz-co-bTP), P(tCz-co-CPDT), P(tCz-co-DTC), and P(tCz-co-CPDTK) films are estimated to be 43.0% at 967 nm, 28.7% at 864 nm, 43.6% at 870 nm, and 24.5% at 984 nm, respectively. Five electrochromic devices (ECDs) are assembled using the tCz-based homopolymer and copolymers as coloring electrodes, and poly(2,2-dimethyl-3,4-propylenedioxythiophene) (PProDOT-Me2) as the complementary electrode. P(tCz-co-DTC)/PProDOT-Me2 ECD reveals high transmittance change (45.9% at 624 nm), P(tCz-co-CPDTK)/PProDOT-Me2 ECD shows high η (513.0 cm2 C−1 at 582 nm), and P(tCz-co-bTP)/PProDOT-Me2 ECD presents short switching time (less than 0.4 s) at 628 nm. Moreover, these ECDs show satisfactory redox stability and open circuit stability.
Development of Eco-Friendly Polymer Foam Using Overcoat Technology of Deodorant
Authors: Lee Jung Joon , Cho Mi Yeon , Kim Bo-Hyun , Lee Sunjong
Published: October 2018

Development of eco-friendly polymer foams is an urgent research topic because of the serious environmental pollution caused by trash heaps and the time-release of harmful gases. Polymer PVC foam using azodicarbonamide as a chemical foaming agent has been highly requested for further improvement due to the residual ammonia gas that continuously leaks out. Here, we demonstrate an effective and costless process for the reduction of releasing ammonia from PVC foams using the overcoat technology of deodorants. We have selected four candidate materials, gelite, zeolite, terra alba, and fumed silica as original materials for the deodorant of ammonia, and they showed an ammonia deodorization rate (ADR) of over 80% without any treatment except the fumed silica. When we over-coated the UV-curing agent mixed deodorants on the PVC foams (thickness ~300 µm), the ADR of the terra alba and zeolite complex foams was remarkably higher than 90%, however, the specific gravity and chromaticity were not changed within 20%. This indicates that our developed process using deodorant layer for ammonia reduction has a high potential for the production of eco-friendly polymer foams.
Robot Coverage Path Planning under Uncertainty Using Knowledge Inference and Hedge Algebras
Authors: Van Pham Hai , Moore Philip
Published: October 2018

Human behaviour demonstrates environmental awareness and self-awareness which is used to arrive at decisions and actions or reach conclusions based on reasoning and inference. Environmental awareness and self-awareness are traits which autonomous robotic systems must have to effectively plan an optimal route and operate in dynamic operating environments. This paper proposes a novel approach to enable autonomous robotic systems to achieve efficient coverage path planning, which combines adaptation with knowledge reasoning techniques and hedge algebras to achieve optimal coverage path planning in multiple decision-making under dynamic operating environments. To evaluate the proposed approach we have implemented it in a mobile cleaning robot. The results demonstrate the ability to avoid static and dynamic (moving) obstacles while achieving efficient coverage path planning with low repetition rates. While alternative current coverage path planning algorithms have achieved acceptable results, our reported results have demonstrated a significant performance improvement over the alternative coverage path planning algorithms.
Effects of Gd, Y Content on the Microstructure and Mechanical Properties of Mg-Gd-Y-Nd-Zr Alloy
Authors: Tang Changping , Wu Kai , Liu Wenhui , Feng Di , Wang Xuezhao , Miao Guodong , Yang Maomao , Liu Xiao , Li Quan
Published: October 2018

The effects of Gd, Y content on the microstructure and mechanical properties of Mg-Gd-Y-Nd-Zr alloy were investigated using hardness measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and uniaxial tensile testing. The results indicate that the alloys in as-cast condition mainly consist of α-Mg matrix and non-equilibrium eutectic Mg5.05RE (RE = Gd, Y, Nd). After solution treatment, the non-equilibrium eutectics dissolved into the matrix but some block shaped RE-rich particles were left at the grain boundaries and within grains. These particles are especially Y-rich and deteriorate the mechanical properties of the alloys. Both the compositions of the eutectic and the block shaped particle were independent of the total Gd, Y content of the alloys, but the number of the particles increases as the total Gd, Y content increases. The ultimate tensile strength increases as the total Gd, Y content decreases. A Mg-5.56Gd-3.38Y-1.11Nd-0.48Zr alloy with the highest ultimate tensile strength of 280 MPa and an elongation of 1.3% was fabricated. The high strength is attributed to the age hardening behavior and the decrease in block shaped particles.
Material Behavior Description for a Large Range of Strain Rates from Low to High Temperatures: Application to High Strength Steel
Authors: Simon Pierre , Demarty Yaël , Rusinek Alexis , Voyiadjis George Z.
Published: October 2018

Current needs in the design and optimization of complex protective structures lead to the development of more accurate numerical modelling of impact loadings. The aim of developing such a tool is to be able to predict the protection performance of structures using fewer experiments. Considering only the numerical approach, the most important issue to have a reliable simulation is to focus on the material behavior description in terms of constitutive relations and failure model for high strain rates, large field of temperatures and complex stress states. In this context, the present study deals with the dynamic thermo-mechanical behavior of a high strength steel (HSS) close to the Mars® 190 (Industeel France, Le Creusot, France). For the considered application, the material can undergo both quasi-static and dynamic loadings. Thus, the studied strain rate range is varying from 10−3–104 s−1. Due to the fast loading time, the local temperature increase during dynamic loading induces a thermal softening. The temperature sensitivity has been studied up to 473 K under quasi-static and dynamic conditions. Low temperature measurements (lower than the room temperature) are also reported in term of σ − ε | ε ˙ , T curves. Experimental results are then used to identify the parameters of several constitutive relations, such as the model developed initially by Johnson and Cook; Voyiadjis and Abed; and Rusinek and Klepaczko respectively termed Johnson–Cook (JC), Voyiadjis–Abed (VA), and Rusinek–Klepaczko (RK). Finally, comparisons between experimental results and model predictions are reported and compared.
Metabolomic Analyses Reveal Extensive Progenitor Cell Deficiencies in a Mouse Model of Duchenne Muscular Dystrophy
Authors: Joseph Josiane , Cho Dong Seong , Doles Jason D.
Published: October 2018

Duchenne muscular dystrophy (DMD) is a musculoskeletal disorder that causes severe morbidity and reduced lifespan. Individuals with DMD have an X-linked mutation that impairs their ability to produce functional dystrophin protein in muscle. No cure exists for this disease and the few therapies that are available do not dramatically delay disease progression. Thus, there is a need to better understand the mechanisms underlying DMD which may ultimately lead to improved treatment options. The muscular dystrophy (MDX) mouse model is frequently used to explore DMD disease traits. Though some studies of metabolism in dystrophic mice exist, few have characterized metabolic profiles of supporting cells in the diseased environment. Using nontargeted metabolomics we characterized metabolic alterations in muscle satellite cells (SCs) and serum of MDX mice. Additionally, live-cell imaging revealed MDX-derived adipose progenitor cell (APC) defects. Finally, metabolomic studies revealed a striking elevation of acylcarnitines in MDX APCs, which we show can inhibit APC proliferation. Together, these studies highlight widespread metabolic alterations in multiple progenitor cell types and serum from MDX mice and implicate dystrophy-associated metabolite imbalances in APCs as a potential contributor to adipose tissue disequilibrium in DMD.
Mechanical Fatigue Resistance of Piezoelectric PVDF Polymers
Authors: Shin Youn-Hwan , Jung Inki , Park Hyunchul , Pyeon Jung Joon , Son Jeong Gon , Koo Chong Min , Kim Sangtae , Kang Chong-Yun
Published: October 2018

The fatigue resistance of piezoelectric PVDF has been under question in recent years. While some report that a significant degradation occurs after 106 cycles of repeated voltage input, others report that the reported degradation originates from the degraded metal electrodes instead of the piezoelectric PVDF itself. Here, we report the piezoelectric response and remnant polarization of PVDF during 107 cycles of repeated compression and tension, with silver paste-based electrodes to eliminate any electrode effect. After applying repeated tension and compression of 1.8% for 107 times, we do not observe any notable decrease in the output voltage generated by PVDF layers. The results from tension experiments show stable remnant polarization of 5.5 μC/cm2, however, the remnant polarization measured after repeated compression exhibits a 7% decrease as opposed to the tensed PVDF. These results suggest a possible anisotropic response to stress direction. The phase analyses by Raman spectroscopy reveals no significant change in the phase content, demonstrating the fatigue resistance of PVDF.
New Nitrogen Compounds Coupled to Phenolic Units with Antioxidant and Antifungal Activities: Synthesis and Structure–Activity Relationship
Authors: Bettencourt Ana , Castro Marián , Silva João , Fernandes Francisco , Coutinho Olga , Sousa M. João , Proença M. Fernanda , Areias Filipe
Published: October 2018

A selection of 1-amino-2-arylidenamine-1,2-(dicyano)ethenes 3 was synthesized and cyclized to 2-aryl-4,5-dicyano-1H-imidazoles 4 upon reflux in ethyl acetate/acetonitrile, in the presence of manganese dioxide. These compounds were tested for their antioxidant capacity by cyclic voltammetry, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and deoxyribose degradation assays. The minimum inhibitory concentration of all compounds was evaluated against two yeast species, Saccharomyces cerevisiae and Candida albicans. Their toxicity was tested in mammal fibroblasts. Among the synthesised compounds, two presented dual antioxidant/antifungal activity without toxic effects in fibroblasts. The new compounds synthesized in this work are potential biochemical tools and/or therapeutic drugs.
Takeover Requests in Highly Automated Truck Driving: How Do the Amount and Type of Additional Information Influence the Driver–Automation Interaction?
Authors: Richardson Natalie T. , Flohr Lukas , Michel Britta
Published: October 2018

Vehicle automation is linked to various benefits, such as increase in fuel and transport efficiency as well as increase in driving comfort. However, automation also comes with a variety of possible downsides, e.g., loss of situational awareness, loss of skills, and inappropriate trust levels regarding system functionality. Drawbacks differ at different automation levels. As highly automated driving (HAD, level 3) requires the driver to take over the driving task in critical situations within a limited period of time, the need for an appropriate human–machine interface (HMI) arises. To foster adequate and efficient human–machine interaction, this contribution presents a user-centered, iterative approach for HMI evaluation of highly automated truck driving. For HMI evaluation, a driving simulator study [n = 32] using a dynamic truck driving simulator was conducted to let users experience the HMI in a semi-real driving context. Participants rated three HMI concepts, differing in their informational content for HAD regarding acceptance, workload, user experience, and controllability. Results showed that all three HMI concepts achieved good to very good results in these measures. Overall, HMI concepts offering more information to the driver about the HAD system showed significantly higher ratings, depicting the positive effect of additional information on the driver–automation interaction.
Nanoscale Assembly of Copper Bearing-Sleeve via Cold-Welding: A Molecular Dynamics Study
Authors: Zhou Hongjian , Li Jiejie , Xian Yuehui , Hu Guoming , Li Xiaoyong , Xia Re
Published: October 2018

A bearing is an important component in contemporary machinery and equipment, whose main function is to support the mechanical rotator, reduce the friction coefficient during its movement, and guarantee the turning accuracy. However, assembly of a nanoscale bearing and sleeve is a challenging process for micro-nano mechanical manufacturers. Hence, we show the cold-welding mechanism of a copper nanobearing-nanosleeve via molecular dynamic simulations. We demonstrate that it is feasible to assemble a bearing and sleeve at the nanoscale to form a stable mechanism. The effect of temperature in the range of 150 to 750 K is investigated. As the temperature rises, the mechanical strength and the weld stress of the welded structures markedly decrease, accompanied by the observation of increasing disorder magnitude. This comparison study is believed to facilitate future mechanical processing and structural nano-assembly of metallic elements for better mechanical performance.
Synthesis and Characterization of Multi-Walled Carbon Nanotube/Graphene Nanoplatelet Hybrid Film for Flexible Strain Sensors
Authors: Huang JianRen , Her Shiuh-Chuan , Yang XiaoXiang , Zhi MaNan
Published: October 2018

Graphene nanoplatelet (GNP) and multi-walled carbon nanotube (MWCNT) hybrid films were prepared with the aid of surfactant Triton X-100 and sonication through a vacuum filtration process. The influence of GNP content ranging from 0 to 50 wt.% on the mechanical and electrical properties was investigated using the tensile test and Hall effect measurement, respectively. It showed that the tensile strength of the hybrid film is decreasing with the increase of the GNP content while the electrical conductivity exhibits an opposite trend. The effectiveness of the MWCNT/GNP hybrid film as a strain sensor is presented. The specimen is subjected to a flexural loading, and the electrical resistance measured by a two-point probe method is found to be function of applied strain. Experimental results demonstrate that there are two different linear strain-sensing stages (0–0.2% and 0.2–1%) in the resistance of the hybrid film with applied strain. The strain sensitivity is increasing with the increase of the GNP content. In addition, the repeatability and stability of the strain sensitivity of the hybrid film were conformed through the cyclic loading–unloading tests. The MWCNT/GNP hybrid film shows promising application for strain sensing.
Spin-Coated CH3NH3PbBr3 Film Consisting of Micron-Scale Single Crystals Assisted with a Benzophenone Crystallizing Agent and Its Application in Perovskite Light-Emitting Diodes
Authors: Gao Zhan , Zheng Yifan , Zhao Dan , Yu Junsheng
Published: October 2018

Owing to the superior properties of optical and electronic properties, perovskite single crystals have been in high demand recently. However, the growth of large-sized single crystals requires several processing steps and a long growth time, which engenders great difficulties in device integration. Herein, benzophenone (BP) was firstly introduced as a crystallizing agent to facilitate the construction of a high-quality CH3NH3PbBr3 (MAPbBr3) film consisting of micron-scale single crystals in a one-step spin-coating method. We studied the influence of the BP concentration upon the size and shape of the micron-scale single crystals. Moreover, due to the enhanced morphology of the MAPbBr3 film with low-defect micron-scale single crystals, perovskite light-emitting diodes (PeLEDs) have been demonstrated with a maximum luminance of 1057.6 cd/m2 and a turn-on voltage as low as 2.25 V. This approach not only proposes a concise and highly repeatable method for the formation of micron-scale perovskite single crystals, but also paves a way for the realization of efficient PeLEDs.
Fish Intake, Circulating Mercury and Mortality in Renal Transplant Recipients
Authors: Sotomayor Camilo , Gomes-Neto António , Gans Rijk , De Borst Martin , Berger Stefan , Rodrigo Ramón , Navis Gerjan , Touw Daan , Bakker Stephan
Published: October 2018

Marine-derived omega-3 polyunsaturated fatty acids (n-3 PUFAs) are inversely associated with cardiovascular and all-cause mortality in renal transplant recipients (RTRs). Recommendations to increase marine-derived n-3 PUFAs by increasing fish intake may have a drawback in concomitant stimulation of mercury intake, which could lead to higher circulating mercury concentrations and mitigation of otherwise beneficial effects of n-3 PUFAs. We aimed to monitor circulating mercury concentrations, and to prospectively evaluate whether it counteracts the potential association between fish intake and cardiovascular and all-cause mortality in a cohort of RTRs (n = 604, 53 ± 13 years-old, 57% men) with long-term follow-up (median of 5.4 years; 121 deaths). Circulating mercury concentration (median 0.30 (IQR 0.14–0.63) µg/L) positively associated with fish intake (std. β = 0.21, p < 0.001). Multivariable-adjusted Cox-proportional hazards regression analyses showed that prior to, and after additional adjustment for circulating mercury concentrations, fish intake was inversely associated with both cardiovascular (HR 0.75, 95% CI 0.58–0.96; and, HR 0.75, 95% CI 0.58–0.97, respectively) and all-cause mortality (HR 0.84, 95% CI 0.72–0.97; and, HR 0.86, 95% CI 0.74–0.99, respectively). Secondary analyses accounting for marine-derived n-3 PUFAs intake revealed associations of similar magnitude. In conclusion, we found no evidence of a counteracting effect conferred by circulating mercury concentrations on the associations between fish and marine-derived n-3 PUFAs intake and the risks of cardiovascular and all-cause mortality in RTRs.
Serum Carotenoids Reveal Poor Fruit and Vegetable Intake among Schoolchildren in Burkina Faso
Authors: Bationo Jean Fidèle , Zeba Augustin N. , Abbeddou Souheila , Coulibaly Nadine D. , Sombier Olivier O. , Sheftel Jesse , Bassole Imael Henri Nestor , Barro Nicolas , Ouedraogo Jean Bosco , Tanumihardjo Sherry A.
Published: October 2018

The health benefits of fruits and vegetables are well-documented. Those rich in provitamin A carotenoids are good sources of vitamin A. This cross-sectional study indirectly assessed fruit and vegetable intakes using serum carotenoids in 193 schoolchildren aged 7 to 12 years in the Western part of Burkina Faso. The mean total serum carotenoid concentration was 0.23 ± 0.29 µmol/L, which included α- and β-carotene, lutein, and β-cryptoxanthin, and determined with serum retinol concentrations in a single analysis with high performance liquid chromatography. Serum retinol concentration was 0.80 ± 0.35 µmol/L with 46% of children (n = 88) having low values <0.7 µmol/L. Total serum carotene (the sum of α- and β-carotene) concentration was 0.13 ± 0.24 µmol/L, well below the reference range of 0.9–3.7 µmol carotene/L used to assess habitual intake of fruits and vegetables. Individual carotenoid concentrations were determined for α-carotene (0.01 ± 0.05 µmol/L), β-carotene (0.17 ± 0.24 µmol/L), β-cryptoxanthin (0.07 ± 0.06 µmol/L), and lutein (0.06 ± 0.05 µmol/L). These results confirm the previously measured high prevalence of low serum vitamin A concentrations and adds information about low serum carotenoids among schoolchildren suggesting that they have low intakes of provitamin A-rich fruits and vegetables.