bluuebunny/crossref_metadata_2025 huggingface dataset:
Grading of aortic regurgitation by cardiovascular magnetic resonance and pulsed Doppler of the left subclavian artery: harmonizing grading scales between imaging modalities
Authors: Spampinato Ricardo A. , Jahnke Cosima , Paetsch Ingo , Hilbert Sebastian , Löbe Susanne , Lindemann Frank , Strotdrees Elfriede , Hindricks Gerhard , Borger Michael A.
Published: April 2020

Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) are current standard for assessing aortic regurgitation (AR). Regurgitant fraction (RF) can also be estimated by Doppler examination of the left subclavian artery (LSA-Doppler). However, a comparison of AR grading scales using these methods and a TTE multiparametric approach as reference is lacking. We evaluated the severity of AR in 73 patients (58 ± 15 years; 57 men), with a wide spectrum of AR of the native valve. Using a recommended TTE multiparametric approach the AR was divided in none/trace (n = 12), mild (n = 23), moderate (n = 12), and severe (n = 26). RF was evaluated by LSA-Doppler (ratio between diastolic and systolic velocity–time integrals) and by CMR phase-contrast imaging (performed in the aorta 1 cm above the aortic valve); the grading scales were then calculated. There were a good correlation between all methods, but mean RF values were greater with TTE compared with LSA-Doppler and CMR (39 ± 16% vs. 35 ± 18% vs. 32 ± 20%, respectively; p < 0.037). Mean differences in RF values between methods were significant in the groups with mild and moderate AR. Grading scales that best defined the TTE derived AR severity using CMR were: mild, < 21%; moderate, 22 to 41%; and severe, > 42%; and using LSA-Doppler: mild, < 29%; moderate, 30 to 44%; and severe, > 45%. RF values for AR grading using TTE, LSA-Doppler and CMR correlate well but differ in groups with mild and moderate AR when using a recognized multiparametric echocardiographic approach. Clinical prospective studies should validate these proposed modality adjusted grading scales.
How software engineering research aligns with design science: a review
Authors: Engström Emelie , Storey Margaret-Anne , Runeson Per , Höst Martin , Baldassarre Maria Teresa
Published: April 2020

Background

Assessing and communicating software engineering research can be challenging. Design science is recognized as an appropriate research paradigm for applied research, but is rarely explicitly used as a way to present planned or achieved research contributions in software engineering. Applying the design science lens to software engineering research may improve the assessment and communication of research contributions.

Aim

The aim of this study is 1) to understand whether the design science lens helps summarize and assess software engineering research contributions, and 2) to characterize different types of design science contributions in the software engineering literature.

Method

In previous research, we developed a visual abstract template, summarizing the core constructs of the design science paradigm. In this study, we use this template in a review of a set of 38 award winning software engineering publications to extract, analyze and characterize their design science contributions.

Results

We identified five clusters of papers, classifying them according to their different types of design science contributions.

Conclusions

The design science lens helps emphasize the theoretical contribution of research output—in terms of technological rules—and reflect on the practical relevance, novelty and rigor of the rules proposed by the research.
Sex ratios deviate across killifish species without clear links to life history
Authors: Sowersby Will , Gonzalez-Voyer Alejandro , Rogell Björn
Published: April 2020

Sex ratios can differ from an expected equal proportion of males and females, carrying substantial implications for our understanding of how mating systems evolve. Typically, macro-evolutionary studies have been conducted without assessing how deviations from an equal sex ratio could be explained by sex-biased mortality or dispersal. Our understanding of sex ratio evolution independent of these confounds, in addition to any putative links between skewed sex ratios and other factors (e.g. life history), therefore remains largely unexplored. Here, we conducted an exploratory study investigating differences in sex ratios across closely related species while controlling for extrinsic mortality. We also tested two factors, non-overlapping/overlapping generations and the social environment, which have both been hypothesised to affect sex ratios. Specifically, we raised 15 species of killifish, which have either overlapping or discrete generations, under both solitary and social treatments. We found substantial divergences in sex ratios across closely related species, which exhibited both male and female biases. In conjunction with a low phylogenetic signal, our results suggest that sex ratios can evolve rapidly in this group. However, we found no evidence that overlapping generations or the social environment affected sex biases, suggesting that other factors drive the rapid evolution of sex ratios in killifishes.
Predicting Intense Levels of Child Anxiety During Anesthesia Induction at Hospital Arrival
Authors: Eijlers Robin , Staals Lonneke M. , Legerstee Jeroen S. , Berghmans Johan M. , Strabbing Elske M. , van der Schroeff Marc P. , Wijnen René M. H. , Kind Laura S. , Hillegers Manon H. J. , Dierckx Bram , Utens Elisabeth M. W. J.
Published: April 2020

In children, intense levels of anxiety during anesthetic induction are associated with a higher risk of pain, poor recovery, and emergence delirium. Therefore, it is important to identify these high-risk children at hospital arrival. The current study examined internalizing behavior (Child Behavior Checklist, CBCL) and state anxiety measures (modified Yale Preoperative Anxiety Scale, mYPAS, and State Trait Anxiety Inventory for Children, STAIC) at hospital arrival as predictors of anxiety during induction of anesthesia. One hundred children (aged 4 to 12 years) undergoing elective daycare surgery were included. The STAIC and mYPAS at hospital arrival were significant predictors of anxiety during induction, whereas CBCL was not. The STAIC state form at hospital arrival was the strongest predictor and could be used to identify children who will experience intense levels of anxiety during anesthetic induction, with sufficient to good diagnostic accuracy. Using the STAIC at hospital arrival allows targeted interventions to reduce anxiety in children.
Gambling in Young Adults Aged 17–24 Years: A Population-Based Study
Authors: Hollén Linda , Dörner Rita , Griffiths Mark D. , Emond Alan
Published: April 2020

A large contemporary UK cohort study, the Avon Longitudinal Study of Parents and Children, was used to investigate gambling behavior and to explore the antecedents of regular gambling in the 17–24-year age group. Participants completed computer-administered gambling surveys in research clinics, on paper, and online. The sample sizes were 3566 at age 17 years, 3940 at 20 years, and 3841 at 24 years; only 1672 completed all three surveys. Participation in gambling in the last year was reported by 54% of 17-year-olds, rising to 68% at 20 years, and 66% at 24 years, with little overall variance. Regular (weekly) gambling showed a strong gender effect, increasing among young men from 13% at 17 years to 18% at 20 years, and 17% at 24 years. Although gambling frequency increased between the ages of 17 and 20 years, gambling behaviors showed little variance between 20 and 24 years, except online gambling and betting on horseraces. The commonest forms of gambling were playing scratchcards, playing the lottery, and private betting with friends. Gambling on activities via the internet increased markedly between 17 and 24 years, especially among males. In the fully adjusted model, individual antecedents of regular gambling were being male, and having a low IQ, an external locus of control, and high sensation seeking scores. Parental gambling behavior and maternal educational background were associated with regular gambling in both sexes. Regular gambling was associated with smoking cigarettes and frequent and harmful use of alcohol, but no associations with depression were found.
What Happens to Efficiency and Equity? The Cost Implications of Developmental Education Reform
Authors: Mokher Christine G. , Park-Gaghan Toby J. , Hu Shouping
Published: April 2020

Florida passed legislation in 2013 that exempted many students from developmental education, and required colleges to implement new instructional modalities for optional developmental education courses. This paper uses an economic model of remediation to examine how changes in college course taking before and after the reform altered costs to completing introductory college-level courses in math and English for students and institutions, and whether cost savings differ by racial/ethnic subgroup. We also take into account changes in short-term costs relative to course completion rates to examine whether the reform is cost effective overall. We find that the total cost per completer (including costs to both students and institutions) decreased after the reform by $894 in English and $1851 in math. This resulted in efficiency gains of 34% in English and 30% in math. The results from Florida provide promising evidence that statewide developmental education reforms may be an effective mechanism for reducing costs to students and institutions. Reform efforts may also help to reduce racial/ethnic gaps in the costs to gateway completion in both subject areas, which has important implications for equity.
Digital transformation: a review, synthesis and opportunities for future research
Authors: Nadkarni Swen , Prügl Reinhard
Published: April 2020

In the last years, scholarly attention was on a steady rise leading to a significant increase in the number of papers addressing different technological and organizational aspects of digital transformation. In this paper, we consolidate existing findings which mainly stem from the literature of information systems, map the territory by sharing important macro- and micro-level observations, and propose future research opportunities for this pervasive field. The paper systematically reviews 58 peer-reviewed studies published between 2001 and 2019, dealing with different aspects of digital transformation. Emerging from our review, we develop inductive thematic maps which identify technology and actor as the two aggregate dimensions of digital transformation. For each dimension, we derive further units of analysis (nine core themes in total) which help to disentangle the particularities of digital transformation processes and thereby emphasize the most influential and unique antecedents and consequences. In a second step, in order to assist in breaking down disciplinary silos and strengthen the management perspective, we supplement the resulting state-of-the-art of digital transformation by integrating cross-disciplinary contributions from reviewing 28 papers on technological disruption and 32 papers on corporate entrepreneurship. The review reveals that certain aspects, such as the pace of transformation, the culture and work environment, or the middle management perspective are significantly underdeveloped.
Growth Region Impacts Cell Wall Properties and Hard-to-Cook Phenotype of Canned Navy Beans (Phaseolus vulgaris)
Authors: Chu Jin , Ho Peter , Orfila Caroline
Published: April 2020

Cellular mechanisms underpinning the hard-to-cook phenomenon are poorly understood. Navy beans (Phaseolus vulgaris) from the same cultivar but grown in different regions of North America showed different canning characteristics. Up to 46.4% more force was required to disrupt hard beans (HB) grown in Ontario compared with soft beans (SB) grown in Manitoba. HB absorbed 12.5% and 14.7% less water during blanching and canning, respectively. Microscopic assessment revealed that canning led to swelling of middle lamella and cell walls, but preservation of cell adhesion in both types of beans. Immunofluorescence microscopy showed reduced labelling of methyl-esterified homogalacturonan (HG) and more non-methyl-esterified HG and arabinan epitopes in HB. Compositional analysis indicated that the polysaccharides from HB were less water soluble and enriched in neutral sugars, including 46.5% more arabinose and 51.8% more galactose than in SB. ELISA analysis of polymers in the canning medium supported the increased solubility of cell wall polymers in SB. In the same cultivar, growth region affects cell wall properties with consequences for processing, eating and nutritional quality.
Cold Atmospheric Plasma Inactivation of Microbial Spores Compared on Reference Surfaces and Powder Particles
Authors: Beyrer Michael , Smeu Irina , Martinet David , Howling Alan , Pina-Pérez Maria Consuelo , Ellert Christoph
Published: April 2020

Heat-resistant spores on a dry, heat- and water-sensitive food matrix are difficult to inactivate. Radioactive or X-ray exposure is allowed and accepted only for some selected commodities. Non-thermal atmospheric pressure plasma treatments could offer an efficient, fast, and chemical-free solution. The effectiveness of direct contact cold atmospheric plasma (CAP) generated by a dielectric barrier discharge (DBD) device and air as process gas was evaluated against spores of Bacillus spp., Geobacillus spp., and Penicillium spp. A maximum of 3 log10 cycles of inactivation was achieved for B. coagulans spores exposed for only 10 s at low surface energy of 0.18 W/cm2 determined directly at the electrodes. This corresponds to an initial decimal reduction time of D1 = 0.1 min. Spores of B. subtilis are the most resistant amongst the studied strains (D1 = 1.4 min). The determining parameter in the modeling of the inactivation curve is surface energy. Non-porous, native starch granules or shells from diatoms, a highly porous material, were also contaminated with spores and treated by DBD CAP. The inactivation level was significantly reduced by the presence of powders. Considering plasma diagnostics, it can be concluded that the spore shell is the primary and main target for a plasma-induced inactivation. The inactivation affect scales with surface energy and can be controlled directly via process time and/or discharge power.
Dried Biomass of Arthrospira platensis Inhibits Growth of Aureobasidium pullulans LW14 and Some Bacteria When Added to Unpasteurised Apple Juice
Authors: Wajda Łukasz , Rękas Zuzanna , Tarko Tomasz , Duda-Chodak Aleksandra , Liebersbach Aleksandra , Makarewicz Małgorzata
Published: April 2020

The main goal was to evaluate if dried cyanobacterium (Arthrospira platensis) biomass added to unpasteurised apple juice could inhibit growth of fungi dominant in apples and which fraction of cyanobacterium biomass contributed to this phenomenon. A. platensis biomass, its protein and/or polysaccharide fraction were added to the sterilised apple juice inoculated with Aureobasidium pullulans LW14 and stored at 4 °C for 96 h. Samples were tested against number of fungi and selected physical–chemical parameters. In the last research stage, protein fraction was added to the unpasteurised apple juice inoculated with A. pullulans LW14 to test its potency against fungi, lactic acid bacteria and acetic acid bacteria. When A. platensis biomass was added to the sterilised apple juice (1.15% w/v), it effectively inhibited growth of A. pullulans LW14 and the metabolism of all analysed sugars (glucose, sucrose and fructose). Protein fraction added to the sterilised apple juice contributed significantly to mycostatic properties of A. platensis. When protein fraction was added to unpasteurised apple juice, the same conclusions were obtained, however, except for inhibiting growth of A. platensis LW14, it inhibited growth of some bacteria.
Alleviation of drought stress by melatonin foliar treatment on two flax varieties under sandy soil
Authors: Sadak Mervat Shamoon , Bakry Bakry Ahmed
Published: April 2020

The role of melatonin treatments on improving plant tolerance against drought stress is clear, while its special role and influences are poorly investigated. Thus, the effect of external treatment with different concentrations (2.5, 5.0 and 7.5 mM) of melatonin on two varieties of flax plant (Letwania-9 and Sakha-2) growth, some biochemical aspects and yield under normal [100% water irrigation requirements (WIR)] and drought stress conditions (75% and 50% WIR) in sandy soil were investigated in this study. Drought stress decreased significantly different growth parameters, photosynthetic pigments, yield and yield components of the two studied flax varieties. While, it increased significantly phenolic contents, total soluble sugars (TSS), proline and free amino acids as well as some antioxidant enzymes (superoxide dismutase, catalase, peroxidase and polyphenol oxidase). Meanwhile, external treatment of melatonin (2.5, 5.0 and 7.5 mM) increased significantly different growth and yield parameters as well as the studied biochemical and physiological aspects under 100% WIR. Also, melatonin treatment could alleviate the adverse effects of drought stress and increased significantly growth parameters, yield and quality of the two varieties of flax plant via improving photosynthetic pigments, indole acetic acid, phenolic, TSS, proline free amino acids contents and antioxidant enzyme systems, as compared with their corresponding untreated controls. Foliar treatment of 5.0 mM melatonin showed the greatest growth, the studied biochemical aspects and yield quantity and quality of Letwania-9 and Sakha-2 varieties of flax plants either at normal irrigation or under stress conditions. Finally we can conclude that, melatonin treatment improved and alleviated the reduced effect of drought stress on growth and yield of two flax varieties through enhancing photosynthetic pigment, osmoptrotectants and antioxidant enzyme systems. 5 mM was the most effective concentration.
The influence of moisture content on coal deformation and coal permeability during coalbed methane (CBM) production in wet reservoirs
Authors: Talapatra Akash , Karim Md. Mostafijul
Published: April 2020

Moisture adsorption in the coal seams affects the gas adsorption capacity and can alter the coal deformation and permeability criteria of the coal seam. The effect of dynamic loss of moisture content, both on moisture and gas sorption-induced coal swelling/shrinkage strains, during the coalbed methane (CBM) production, is crucial. This study investigates the interactions among coal matrix, absorbed gas, and moisture content, based on the coal swelling/shrinkage strains and gas adsorption decay criteria. Consequently, a mathematical model of the coal deformation is developed for the proper evaluation of the moisture effect. For developing the model, this paper considers the standard gas flow and moisture loss equations to assess the volumetric content, equilibrium pressure, and density of the moisture. Finally, it comprehensively analyzes the sensitive factors and effects of elemental parameters of moisture content on coal deformation and coal permeability. The results show that moisture content at adsorbed state significantly changes the coal swelling/shrinkage strain and that distorted swelling and shrinkage characteristics can promote the permeability alternation in wet coal reservoirs. Moreover, the intermolecular attraction between the coal structure and the moisture content has a significant effect on methane adsorption/desorption-induced deformation in coal structure. This study also designs the coal deformation strains as a function of moisture content by the Langmuir type model and evaluates the hysteresis rate between the swelling and shrinkage characteristics. The findings of this paper can characterize a wet coal reserve for CBM production and anticipate future production under different operating conditions.
Experimental studies of CO2-brine-rock interaction effects on permeability alteration during CO2-EOR
Authors: Okhovat Mohammad Reza , Hassani Kamran , Rostami Behzad , Khosravi Maryam
Published: April 2020

Carbon dioxide (CO2) sequestration through CO2 enhanced oil recovery (EOR) in oil reservoirs is one way to reduce this gas in the atmosphere. Undesirable chemical reactions that occur during these operations can affect the reservoir structure and characteristics. In this study, the effect of CO2-water-rock interaction on the rock permeability alteration and final oil recovery has been evaluated experimentally during CO2 injection into a carbonate rock. The effect of flow rate, displacement type and pressure were investigated during CO2 EOR injection. Different scenarios of miscible/immiscible displacement, secondary/tertiary recovery has been evaluated for different levels of connate water salinity and injection rate. The results show that the severity of damage is directly related to the injection rate, however change in displacement type from miscible to immiscible reduce the intensity of chemical reactions in porous medium. Moreover, in the tertiary CO2 injection, the chemical reactions become more severe due to the higher water saturations. Interestingly, this growth in the level of chemical reactions has a negligible impact on permeability reduction, since the major volume of possible reactions occurs in coarse and high permeable pores. Results reveal that damage is more intense in the case of more saline water.
Use of an Integrated Pan-Cancer Oncology Enrichment Next-Generation Sequencing Assay to Measure Tumour Mutational Burden and Detect Clinically Actionable Variants
Authors: Pestinger Valerie , Smith Matthew , Sillo Toju , Findlay John M. , Laes Jean-Francois , Martin Gerald , Middleton Gary , Taniere Phillipe , Beggs Andrew D.
Published: April 2020

Introduction

The identification of tumour mutational burden (TMB) as a biomarker of response to programmed cell death protein 1 (PD-1) immunotherapy has necessitated the development of genomic assays to measure this. We carried out comprehensive molecular profiling of cancers using the Illumina TruSight Oncology 500 (TSO500) panel and compared these to whole-genome sequencing (WGS).

Methods

Cancer samples derived from formalin-fixed material were profiled on the TSO500 panel, sequenced on an Illumina NextSeq 500 instrument and processed through the TSO500 Docker pipeline. Either FASTQ files (PierianDx) or vcf files (OncoKDM) were processed to understand clinical actionability.

Results

In total, 108 samples (a mixture of colorectal, lung, oesophageal and control samples) were processed via the DNA panel. There was good correlation between TMB, single-nucleotide variants (SNVs), indels and copy-number variations as predicted by TSO500 and WGS (R2 > 0.9) and good reproducibility, with less than 5% variability between repeated controls. For the RNA panel, 13 samples were processed, with all known fusions observed via orthogonal techniques. For clinical actionability, 72 tier 1 variants and 297 tier 2 variants were detected, with clinical trials identified for all patients.

Conclusions

The TSO500 assay accurately measures TMB, microsatellite instability, SNVs, indels, copy-number/structural variation and gene fusions when compared to WGS and orthogonal technologies. Coupled with a clinical annotation pipeline, this provides a powerful methodology for identification of clinically actionable variants.
Frailty, walking ability and self-rated health in predicting institutionalization: an 18-year follow-up study among Finnish community-dwelling older people
Authors: Viljanen Anna , Salminen Marika , Irjala Kerttu , Korhonen Päivi , Wuorela Maarit , Isoaho Raimo , Kivelä Sirkka-Liisa , Vahlberg Tero , Viitanen Matti , Löppönen Minna , Viikari Laura
Published: April 2020

Background

In clinical practice, there is a need for an instrument to screen older people at risk of institutionalization.

Aims

To analyze the association of frailty, walking-ability and self-rated health (SRH) with institutionalization in Finnish community-dwelling older people.

Methods

In this prospective study with 10- and 18-year follow-ups, frailty was assessed using FRAIL Scale (FS) (n = 1087), Frailty Index (FI) (n = 1061) and PRISMA-7 (n = 1055). Walking ability was assessed as self-reported ability to walk 400 m (n = 1101). SRH was assessed by a question of general SRH (n = 1105). Cox regression model was used to analyze the association of the explanatory variables with institutionalization.

Results

The mean age of the participants was 73.0 (range 64.0‒97.0) years. Prevalence of institutionalization was 40.8%. In unadjusted models, frailty was associated with a higher risk of institutionalization by FS in 10-year follow-up, and FI in both follow-ups. Associations by FI persisted after age- and gender-adjustments in both follow-ups. By PRISMA-7, frailty predicted a higher risk of institutionalization in both follow-ups. In unadjusted models, inability to walk 400 m predicted a higher risk of institutionalization in both follow-ups and after adjustments in 10-year follow-up. Poor SRH predicted a higher risk of institutionalization in unadjusted models in both follow-ups and after adjustments in 10-year follow-up.

Discussion

Simple self-reported items of walking ability and SRH seemed to be comparable with frailty indexes in predicting institutionalization among community-dwelling older people in 10-year follow-up.

Conclusions

In clinical practice, self-reported walking ability and SRH could be used to screen those at risk.
Comparison of Changing Population Exposure to Droughts in River Basins of the Tarim and the Indus
Authors: Wang Anqian , Wang Yanjun , Su Buda , Kundzewicz Zbigniew W. , Tao Hui , Wen Shanshan , Qin Jiancheng , Gong Yu , Jiang Tong
Published: April 2020

Droughts are major, large‐scale, weather‐driven natural disasters, on the rise in the changing climate. We project changing population exposure to drought in two vulnerable, adjacent, basins of large rivers, the Tarim River Basin (TRB) and the Indus River Basin (IRB), for the future horizon 2021–2065. Drought events are assessed based on the outputs of multiple Global Climate Models, by applying the Standardized Precipitation Evapotranspiration Index (SPEI) and the Intensity‐Area‐Duration method (IAD). Future population exposure to droughts is evaluated by combining the drought events under three RCP scenarios (RCP2.6, RCP4.5, and RCP8.5) with the projected population from Shared Socioeconomic Pathways (SSPs), acknowledging the recent two‐child policy in China. Results show that frequency of drought events in both river basins could increase in the future, while increase in the TRB is stronger than in the IRB. The areal coverage of drought events in both river basins is projected to be greater in 2021–2065 than in 1961–2005. Increase of frequency and areal coverage in both basins is especially strong for the class of extreme drought events. According to the ensemble mean of multi‐GCMs, population exposure to droughts was 25.0% and 20.9% of the total population in the TRB and the IRB, respectively, in 1961–2005, and it is projected to increase by over 60% for the TRB and to increase by over 30% for the IRB, in 2021–2065.
Surface ligation stage revealed through polarity-dependent fluorescence during perovskite nanocrystal growth
Authors: Sadighian James C. , Crawford Michael L. , Suder Timothy W. , Wong Cathy Y.
Published: April 2020

Selective, polarity-based filtration of a reaction mixture during growth was used to track surface ligation during nanocrystal growth.
Optically controlled hybrid metamaterial of plasmonic spiky gold inbuilt graphene sheets for bimodal imaging guided multimodal therapy
Authors: Jibin Kunnumpurathu , Prasad Jayaram S. , Saranya Giridharan , Shenoy Sachin J. , Maiti Kaustabh K. , Jayasree Ramapurath S.
Published: April 2020

Gold–graphene nanohybrid for simultaneous dual-imaging guided triple therapy as a new paradigm in light-triggered cancer theranostics. The material demonstrates excellent therapeutic efficacy and treatment monitoring features.
Development of photochemical and electrochemical cells for operando X-ray absorption spectroscopy during photocatalytic and electrocatalytic reactions
Authors: Khare Rachit , Jentys Andreas , Lercher Johannes A.
Published: April 2020

Photochemical and electrochemical cells were developed and successfully tested for operando X-ray absorption spectroscopy measurements under realistic reaction conditions.
Mn3O4 nanozymes boost endogenous antioxidant metabolites in cucumber (Cucumis sativus) plant and enhance resistance to salinity stress
Authors: Lu Li , Huang Min , Huang Yuxiong , Corvini Philippe F.-X. , Ji Rong , Zhao Lijuan
Published: April 2020

Mn3O4 nanoenzymes boost endogenous antioxidants in, and enhance resistance of, the cucumber (Cucumis sativus) plant subjected to salinity stress.
Slow relaxation of magnetization for a Tb derivative in a biradical-based lanthanide chain
Authors: Deng Xiaochun , Ma Shuqi , Zhu Mei , Zhang Li , Lv Yaohong
Published: April 2020

Four novel lanthanide-biradical chains have been obtained and the Tb derivative reveals field-induced slow magnetic relaxation behavior with an anisotropy barrier Δ/kB = 22.08 K.
Fabrication of transparent, durable and self-cleaning superhydrophobic coatings for solar cells
Authors: Liang Zihui , Zhou Zezhu , Zhao Li , Dong Binghai , Wang Shimin
Published: April 2020

A superhydrophobic coating with high transparency and ultrahigh adhesive force is prepared for application on the glass covers of solar cells, which also exhibits excellent thermal stability and strong acid–base corrosion resistance.
Dendrite-free and air-stable lithium metal batteries enabled by electroless plating with aluminum fluoride
Authors: Wang Zaisheng , Xu Zhenming , Jin Xiaojing , Li Jianhui , Xu Qingshuai , Chong Yanan , Ye Changchun , Li Weishan , Ye Daiqi , Lu Yingying , Qiu Yongcai
Published: April 2020

A bifunctional composite interphase which is generated on the surface of Li foil through electroless plating with a solution of aluminum fluoride can guide uniform Li plating/stripping behaviors with reduced overpotential and simultaneously improve moisture resistance.
Synthesis of [7]phenacene incorporating tetradecyl chains in the axis positions and its application in field-effect transistors
Authors: Okamoto Hideki , Hamao Shino , Kozasa Keiko , Wang Yanan , Kubozono Yoshihiro , Pan Yong-He , Yen Yu-Hsiang , Hoffmann Germar , Tani Fumito , Goto Kenta
Published: April 2020

Ditetradecyl-substituted [7]phenacene was prepared and applied in thin-film FET devices, displaying higher mobility compared to parent [7]phenacene.
Integer boundary spur considerations for fractional‐N PLL based FMCW radar
Authors: Jordan D.A. , Inggs M.R. , Abdul Gaffar M.Y.
Published: April 2020

Fractional‐N phase locked loops (PLLs) offer a low‐cost solution to the precision frequency ramp requirements of frequency‐modulated continuous‐wave (FMCW) radar. In this application, however, the infamous spurious signals generated by these PLLs have not received adequate analysis. In this Letter, the authors investigate the impact of integer boundary spurs on FMCW radar performance. They show that the offset of these spurs is swept during the course of waveform generation, and that undesirable spur chirps manifest in the beat signal as a result. These spur chirps span the radar's intermediate frequency bandwidth and produce Fresnel ripples in the range profile which reduce spurious‐free dynamic range. They present simulations and measurements that demonstrate how reduction of PLL bandwidth can be used to suppress these spurii.
Spectral efficiency maximisation of full‐duplex enabled relaying SWIPT system with successive interference cancellation and maximal ratio combining
Authors: Peng Xuefei , Li Jiandong
Published: April 2020

In this study, the authors propose a spectral efficiency maximisation problem in power splitting (PS)‐based relaying simultaneous wireless information and power transfer (SWIPT) system with full‐duplex (FD) decode‐and‐forward (DF) ability considering the presence of a direct link. Firstly, the authors establish the system model for PS‐based relaying SWIPT system with FD DF ability considering the presence of a direct link. Secondly, they propose an information decoding scheme considering successive interference cancellation and maximal ratio combining techniques. Further, they formulate the spectral efficiency maximisation problem based on the established system. Then, the formulated problem is solved through the proposed iterative PS ratio algorithm, where the designed information scheme is applied. Finally, the better performance of the proposed scheme is demonstrated through a number of simulations.
Machine learning‐oriented resource allocation in C + L + S bands extended SDM–EONs
Authors: Jashvantbhai Pandya Rahul
Published: April 2020

The enormous growth in the number of smartphones, internet usage, and internet of things applications require high data‐rate transport platforms. Therefore, spectrally and spatially scalable core optical networks are essential. Moreover, the current generation, field existing networks, consume the conventional (C) band of the single‐mode single‐core fibres. The recent studies evidence that the increased traffic occupies the complete C band. To overcome this, the spectral and spatial expansion employing multicore (MC), multimode (MM), and multiband (MB, C + L + S) fibre‐based spatial division multiplexing (SDM)–elastic optical network (EON) is a promising solution. However, dynamic traffic, complex networking with MC–MM–MB–SDM–EON requires dynamic network solutions. To accomplish this, the authors propose the machine learning (ML) oriented route, core, mode, band, and modulation format aware spectrum assignment. Such resource allocation (RA) reduces the impact of the physical layer impairments, inter core cross‐talk, differential mode delay, and mode dependent losses. As per the author's best knowledge, ML‐oriented RA for SDM–EON considering the aforementioned parameters is the first investigation. They propose several RA algorithms to reduce the total network cost with increased fibre capacity. Among all, priority‐based RA comes out as an optimal solution.
Event‐triggered stabilisation for switched delayed differential systems: the input‐to‐state stability
Authors: Suo Jinghui , Wang Zidong , Shen Bo , Alsaadi Fuad E.
Published: April 2020

In this study, the boundedness and the input‐to‐state stabilisation problems are investigated for a kind of switched delayed differential systems with exogenous disturbances. To reduce the communication burden, an event‐triggered strategy is adopted in the feedback control loop to stabilise the addressed switched delayed differential systems. The notions of boundedness and input‐to‐state practical stability are employed to characterise the control objectives in the presence of exogenous disturbances, switching signals and event‐triggered schemes. Some upper bounds on the system states are obtained and the Zeno phenomenon is shown to be excluded under the proposed event‐triggered scheme. The gain of the feedback controller, the parameters of the event‐triggering function and the switching signals are jointly designed for the underlying delayed differential systems. At last, a numerical example is exploited to given to demonstrate the effectiveness of the authors' developed control scheme.
Nie–Tan fuzzy method of fault‐tolerant wind energy conversion systems via sampled‐data control
Authors: Gunasekaran Nallappan , Joo Young Hoon
Published: April 2020

In this study, the stabilisation of fault‐tolerant control problem for the variable speed wind turbine (VSWT) model has been investigated with actuator faults by incorporating a Takagi–Sugeno fuzzy technique. To deal with the non‐linear behaviour of VSWT, Nie–Tan fuzzy logic membership is proposed. The sampled‐data input is changed over into a time‐delay term by input delay methodology, and the time delay caused by signal transmission is likewise overseen here. Based on Lyapunov–Krasovskii function theory, a new relaxed sufficient condition with less linear matrix inequality constraints is derived. According to this criterion, a Nie–Tan fuzzy logic controller has been devised to ensure that the closed‐loop system is asymptotically stable. Finally, based on the parameter values, the numerical simulations are performed to validate the derived theoretical results.
Revisiting the simplified IMC tuning rules for low‐order controllers: Novel 2DoF feedback controller
Authors: Rodríguez Carlos , Aranda‐Escolástico Ernesto , Guzmán José Luis , Berenguel Manuel , Hägglund Tore
Published: April 2020

This paper revisites the direct synthesis tuning method of continuous‐time low‐order controllers, and specially PID controllers, for control of time‐delayed single‐input single‐output processes. A setpoint prefilter is included to improve the servo response and integrating load disturbances are accounted for. Robustness is addressed by the feedback controller to obtain the desired maximum sensitivity value. Similar results in step disturbance compensation are obtained with simpler analytical tuning rules when compared to recently reported methods. However, the proposed procedure enables to compensate integrating load disturbances, which are not handled in the other methods.
Revisiting the simplified internal model control tuning rules for low‐order controllers: feedforward controller
Authors: Rodríguez Carlos , Aranda‐Escolástico Ernesto , Guzmán José Luis , Berenguel Manuel , Hägglund Tore
Published: April 2020

In this work, the load disturbance rejection problem is studied. Specifically, the feedforward compensators are considered to reduce the effect of the disturbance in the process' performance. The authors propose simple tuning rules that can be easily applied to a wide range of processes improving the response against the disturbance. The improvement of the proposed method is measured through different performance indices in several simulation examples.
Non‐fragile set‐membership estimation for sensor‐saturated memristive neural networks via weighted try‐once‐discard protocol
Authors: Hu Jun , Yang Yu , Liu Hongjian , Chen Dongyan , Du Junhua
Published: April 2020

This study is concerned with the non‐fragile set‐membership estimation problem for a class of delayed sensor‐saturated memristive neural networks under the premise of communication protocol transmissions. The exogenous noises are unknown but bounded and the activation function satisfies the sector‐bounded condition. In order to schedule the limited network resources, the node's utilisation right of the communication channel at the current instant is determined by the weighted try‐once‐discard protocol. Besides, the estimator gain perturbations are considered to enhance the robustness of estimation method. The major focus of the study is to a design a non‐fragile estimator such that, for all measurement saturation, mixed time‐delays and estimator gain perturbation, the estimation error exists in the ellipsoid by providing a sufficient criterion and the optimal semi‐axes length of the ellipsoid is found by solving a convex optimisation problem. Finally, a simulation example shows that the proposed non‐fragile estimation strategy is effective.
Design and analysis of a kind of rotor ironless high torque density machine using Alnico magnet
Authors: Sheng Zhiyu , Wang Dong
Published: April 2020

Conventional non‐rare‐earth permanent magnet (PM) electrical machine can hardly achieve comparable performance with the neodymium iron boron (NdFeB) machine due to the low coercivity and remanence. To solve this problem, a new kind of electrical machine using only Alnico magnet is proposed in this study. The novel rotor topology eliminates rotor iron core, and thus effectively limits armature reaction and improves torque density. A kind of rapid assessment method for the demagnetisation effect of q current in different slot–pole combinations through magnetomotive force and winding factor is presented and verified by 2D finite‐element analysis. The optimisation of critical dimensions is demonstrated, and the trade‐off between high PM utilisation and low demagnetisation effect is emphasised. After that, the good torque–current linearity and robust to demagnetisation characteristics of the proposed topology are proved through a comparison with two rare‐earth‐free machines. Finally, the performance comparison with a manufactured conventional NdFeB machine under the same volume constraints is provided. The result suggests that the proposed machine has a higher power factor, lower eddy‐current loss, and rare‐earth PM machine comparable torque density.
Improved equivalent circuit model of MMC and influence analysis of simulation time step
Authors: Zhang Lei , Qin Jiangchao , Shi Di , Wang Zhiwei
Published: April 2020

Modelling and simulation of a high voltage‐level modular multilevel converter (MMC) is challenging due to large amount of semiconductor switches, various submodule (SM) circuits, and different operating conditions. Several equivalent models have been proposed for modelling and simulation in system level, which did not consider an industrial or digital controller. To accelerate MMC station design, a highly efficient model is needed with considering control parameters/strategies and accurate dynamics of voltage/current. In this study, an improved equivalent circuit model (ECM) is developed for large‐scale system simulation and MMC station design. The proposed ECM considered the MMCs based on various SM circuits under different operating conditions. It can generate bipolar arm voltage and simulate static compensator under dc fault condition. Based on the proposed ECM, the influences of simulation time step on accuracy/efficiency are investigated by considering the sample period and voltage balancing strategies. This research is conducted based on an MMC‐HVDC system in the PSCAD/EMTDC software. The study results demonstrate the effectiveness of the proposed ECM and show the relationship between simulation accuracy/efficiency and control/simulation parameters for determining simulation time step. Based on study results, the computational efficiency of proposed model is not significantly affected by the complexity of SM circuit.
Combining routing and virtual machine selection algorithm based on multi‐hop cloud wireless access network of mobile edge computing
Authors: Shao Yilin
Published: April 2020

For the problem that mobile devices that are far away from the base station obtain limited wireless resources, which causes high transmission delays, the study proposes a multi‐hop path to assist users who are far away from the base station to use edge computing resources. And it combines cloud radio access network and wireless self‐organising network. The modelling aims to minimise the total energy consumption under the constraints of task delay considering the mobility of mobile devices. Meanwhile, it selects the joint optimisation problem of the path for data transmission and the virtual machine for calculation. This study also introduces the krill herd algorithm and analyses its advantages and disadvantages. The author enhances the global search ability of the algorithm by defining perturbation factors in the random diffusion behaviour and introduces a new strategy of elite selection and retention into the iterative process to improve the convergence accuracy. Finally, the improved krill herd algorithm is used to solve the joint optimisation problem and a better allocation result than the separate resource allocation of calculation and communication is obtained. The experiment proves that the selection algorithm combining virtual machine and routing proposed in this study can achieve the expected results.
Photocatalytic degradation of methyl orange by Bi20TiO32–montmorillonite composite
Authors: Xiang Haichun , Tuo Biyang , Song Xiang
Published: April 2020

To solve the problem of methyl orange (MO) dye wastewater pollution, TiO2–montmorillonite composite (TiO2–MMT) and Bi20TiO32–montmorillonite composite (Bi20TiO32–MMT) were synthesised by the sol–gel method, and they were used for photocatalytic degradation of MO solution. The results showed that TiO2 in TiO2–MMT existed as the anatase type, and Bi20TiO32 in Bi20TiO32–MMT existed as the tetragonal crystal type. When the dosage of the composite was 0.50 g/l, the initial concentration of the MO solution was 20 mg/l, and the pH was 3, the decolourisation rate of MO solution using TiO2–MMT treating was 87.11%, and it reached 98.50% after Bi20TiO32–MMT treating. When Bi20TiO32–MMT was reused four times, the decolourisation rate of the MO solution was only reduced by 3.5%. The photocatalytic degradation between MO solution and Bi20TiO32–MMT complied with the pseudo‐first‐order kinetic equation. Holes and superoxide radicals interacted directly with MO during photocatalytic degradation, which reduced the probability of hole–electron recombination, and improved the photocatalytic degradation property of Bi20TiO32–MMT. Bi20TiO32–MMT has excellent stability property, which makes it a good composite in the treatment of dye wastewater.
Facile route for porous N,S co‐doped TiO2 nanoparticles for visible light‐driven photocatalysis
Authors: Ouyang Weimin , Ji Yajun
Published: April 2020

Herein, porous N,S co‐doped TiO2 nanoparticle (N,S‐TiO2) with the high specific surface area were successfully obtained by a simple oil bath reaction and annealing post‐treatment. Especially, abundant nitrogen and sulphur elements were co‐doped into the resulted TiO2 nanoparticles, which greatly improved the visible light absorption ability of the material. The obtained products were characterised by scanning electron microscope, transmission electron microscopy, Brunauer–Emmett–Teller, X‐ray diffraction, Fourier transform‐infrared spectroscopy, ultraviolet–visible diffuse reflectance spectra and X‐ray photoelectron spectroscopy, respectively. In addition, the obtained N,S‐TiO2 exhibited superior tetracycline photocatalytic degradation activity, which can reach 84.9% within 60 min under irradiation of visible light and preserved excellent stability even after five recycles. Furthermore, the possible formation process of N,S‐TiO2 was discussed. In brief, the obtained N,S‐TiO2 can be used as a potential candidate for visible light‐driven photocatalysis.
Anteriore Uveitis: Klinik, diagnostisches Vorgehen und Behandlungsoptionen
Authors: Pleyer Uwe , Pohlmann Dominika , Rademacher Judith
Published: April 2020

Die anteriore Uveitis umfasst eine Entzündung der Iris und/oder des Ziliarkörpers und ist die häufigste Form der intraokularen Entzündung in der augenärztlichen Praxis. Anamnese und (Leit-)Befunde bei der Spaltlampenuntersuchung bieten oft bereits wichtige Hinweise zur Pathogenese und damit zur weiteren diagnostischen Abklärung und Therapie.
Introduction
Authors: Gvozdanović Jadranka
Published: April 2020

This introduction discusses the construal of temporal categories, their connection with spatial categories and general principles of the patterning of time in language. Transfers between categories and up language hierarchies are frequent types of change. It is shown how aspect may either lose or increase some of its functional load, and how tenses may develop from aspects, or extend into modal domains. General tendencies (such as developments from spatial to temporal categories) and systemic constraints are discussed in relation to the papers in this volume with additional Indo-European examples.
Comparison of cavities and extended defects formed in helium-implanted 6H-SiC at room temperature and 750 °C*
Authors: Liao Qing , Li Bingsheng , Kang Long , Li Xiaogang
Published: April 2020

The formation of cavities in silicon carbide is vitally useful to “smart-cut” and metal gettering in semiconductor industry. In this study, cavities and extended defects formed in helium (He) ions implanted 6H-SiC at room temperature (RT) and 750 °C followed by annealing at 1500 °C are investigated by a combination of transmission electron microscopy and high-resolution electron microscopy. The observed cavities and extended defects are related to the implantation temperature. Heterogeneously distributed cavities and extended defects are observed in the helium-implanted 6H-SiC at RT, while homogeneously distributed cavities and extended defects are formed after He-implanted 6H-SiC at 750 °C. The possible reasons are discussed.