bluuebunny/crossref_metadata_2025 huggingface dataset:
Pseudomonas putida rDNA is a favored site for the expression of biosynthetic genes
Authors: Domröse Andreas , Hage-Hülsmann Jennifer , Thies Stephan , Weihmann Robin , Kruse Luzie , Otto Maike , Wierckx Nick , Jaeger Karl-Erich , Drepper Thomas , Loeschcke Anita
Published: May 2019

Since high-value bacterial secondary metabolites, including antibiotics, are often naturally produced in only low amounts, their efficient biosynthesis typically requires the transfer of entire metabolic pathways into suitable bacterial hosts like Pseudomonas putida. Stable maintenance and sufficient expression of heterologous pathway-encoding genes in host microbes, however, still remain key challenges. In this study, the 21 kb prodigiosin gene cluster from Serratia marcescens was used as a reporter to identify genomic sites in P. putida KT2440 especially suitable for maintenance and expression of pathway genes. After generation of a strain library by random Tn5 transposon-based chromosomal integration of the cluster, 50 strains exhibited strong prodigiosin production. Remarkably, chromosomal integration sites were exclusively identified in the seven rRNA-encoding rrn operons of P. putida. We could further demonstrate that prodigiosin production was mainly dependent on (i) the individual rrn operon where the gene cluster was inserted as well as (ii) the distance between the rrn promoter and the inserted prodigiosin biosynthetic genes. In addition, the recombinant strains showed high stability upon subculturing for many generations. Consequently, our findings demonstrate the general applicability of rDNA loci as chromosomal integration sites for gene cluster expression and recombinant pathway implementation in P. putida KT2440.
Cauliflower mosaic virus transactivator protein (TAV) can suppress nonsense-mediated decay by targeting VARICOSE, a scaffold protein of the decapping complex
Authors: Lukhovitskaya Nina , Ryabova Lyubov A.
Published: May 2019

During pathogenesis, viruses hijack the host cellular machinery to access molecules and sub-cellular structures needed for infection. We have evidence that the multifunctional viral translation transactivator/viroplasmin (TAV) protein from Cauliflower mosaic virus (CaMV) can function as a suppressor of nonsense-mediated mRNA decay (NMD). TAV interacts specifically with a scaffold protein of the decapping complex VARICOSE (VCS) in the yeast two-hybrid system, and co-localizes with components of the decapping complex in planta. Notably, plants transgenic for TAV accumulate endogenous NMD-elicited mRNAs, while decay of AU-rich instability element (ARE)-signal containing mRNAs are not affected. Using an agroinfiltration-based transient assay we confirmed that TAV specifically stabilizes mRNA containing a premature termination codon (PTC) in a VCS-dependent manner. We have identified a TAV motif consisting of 12 of the 520 amino acids in the full-length sequence that is critical for both VCS binding and the NMD suppression effect. Our data suggest that TAV can intercept NMD by targeting the decapping machinery through the scaffold protein VARICOSE, indicating that 5′-3′ mRNA decapping is a late step in NMD-related mRNA degradation in plants.
Increased elasticity of melanoma cells after low-LET proton beam due to actin cytoskeleton rearrangements
Authors: Jasińska-Konior Katarzyna , Wiecheć Olga , Sarna Michał , Panek Agnieszka , Swakoń Jan , Michalik Marta , Urbańska Krystyna , Elas Martyna
Published: May 2019

Cellular response to non-lethal radiation stress include perturbations in DNA repair, angiogenesis, migration, and adhesion, among others. Low-LET proton beam radiation has been shown to induce somewhat different biological response than photon radiation. For example, we have shown that non-lethal doses of proton beam radiation inhibited migration of cells and that this effect persisted long-term. Here, we have examined cellular elasticity and actin cytoskeleton organization in BLM cutaneous melanoma and Mel270 uveal melanoma cells. Proton beam radiation increased cellular elasticity to a greater extent than X-rays and both types of radiation induced changes in actin cytoskeleton organization. Vimentin level increased in BLM cells after both types of radiation. Our data show that cell elasticity increased substantially after low-LET proton beam and persisted long after radiation. This may have significant consequences for the migratory properties of melanoma cells, as well as for the cell susceptibility to therapy.
Brain Activity Related to Sound Symbolism: Cross-modal Effect of an Aurally Presented Phoneme on Judgment of Size
Authors: Itagaki Sachi , Murai Shota , Kobayasi Kohta I.
Published: May 2019

Sound symbolism is the idea that a sound makes a certain impression (e.g., phoneme “p” is associated with an impression of smallness) and could be the psychological basis of the word–meaning association. In this study, we investigated the neural basis of sound symbolism. Subjects were required to compare the visual sizes of standard and target stimuli while listening to syllables assumed to create either a larger or smaller impression. Stimulus–response congruence is defined as the agreement between the target size and the syllable’s impression. Behavioral data showed that the subjects displayed a longer reaction time under the incongruent condition than under the congruent condition, indicating that they tended to associate the object size with certain syllables. We used functional magnetic resonance imaging to evaluate the cerebral activity during the task, and found that both semantic- and phonetic-process-related areas of the brain (left middle temporal gyrus and right superior temporal gyrus, respectively) were activated under the incongruent condition. These results suggest that these regions are associated with the incongruence of sound symbolism.
Streptophyta and Acetic Acid Bacteria Succession Promoted by Brass in Slow Sand Filter System Schmutzdeckes
Authors: Delgado-Gardea Ma. Carmen E. , Tamez-Guerra Patricia , Gomez-Flores Ricardo , Garfio-Aguirre Mariela , Rocha-Gutiérrez Beatriz A. , Romo-Sáenz César I. , Zavala-Díaz de la Serna Francisco Javier , Eroza-de la Vega Gilberto , Sánchez-Ramírez Blanca , González-Horta María del Carmen , Infante-Ramírez María del Rocío
Published: May 2019

Macro- and microorganism activities are important for the effectiveness of the slow sand filtration (SSF), where native microorganisms remove contaminants mainly by substrate competition, predation, and antagonism. The aim of the present study was to evaluate the addition of the oligodynamic metals iron, copper, and brass, inserted separately into SSF to enhance pollutant removal in water samples. Four laboratory-scale SSFs were built and tested: control, iron, copper, and brass. Water analysis included physicochemical evaluation, total and fecal coliform quantification. An analysis on microbial communities in the SSFs schmutzdecke was achieved by using 16S rRNA amplification, the Illumina MiSeq platform, and the QIIME bioinformatics software. The results demonstrated that inorganic and organic contaminants such as coliforms were removed up to 90%. The addition of metals had no significant effect (p > 0.05) on the other parameters. The microbial community analysis demonstrated different compositions of the SSF with brass-influent, where the eukaryote Streptophyta was predominant (31.4%), followed by the acetic acid bacteria Gluconobacter (24.6%), and Acetobacteraceae (7.7%), these genera were absent in the other SSF treatments. In conclusion, the use of a SSF system can be a low cost alternative to reduce microbial contamination in water and thus reduce gastrointestinal diseases in rural areas.
A new perspective on the 137Cs retention mechanism in surface soils during the early stage after the Fukushima nuclear accident
Authors: Koarashi Jun , Nishimura Syusaku , Atarashi-Andoh Mariko , Muto Kotomi , Matsunaga Takeshi
Published: May 2019

The Fukushima Daiichi nuclear power plant accident caused serious radiocesium (137Cs) contamination of the soil in multiple terrestrial ecosystems. Soil is a complex system where minerals, organic matter, and microorganisms interact with each other; therefore, an improved understanding of the interactions of 137Cs with these soil constituents is key to accurately assessing the environmental consequences of the accident. Soil samples were collected from field, orchard, and forest sites in July 2011, separated into three soil fractions with different mineral–organic interaction characteristics using a density fractionation method, and then analyzed for 137Cs content, mineral composition, and organic matter content. The results show that 20–71% of the 137Cs was retained in association with relatively mineral-free, particulate organic matter (POM)-dominant fractions in the orchard and forest surface soil layers. Given the physicochemical and mineralogical properties and the 137Cs extractability of the soils, 137Cs incorporation into the complex structure of POM is likely the main mechanism for 137Cs retention in the surface soil layers. Therefore, our results suggest that a significant fraction of 137Cs is not immediately immobilized by clay minerals and remains potentially mobile and bioavailable in surface layers of organic-rich soils.
Butyrate, a metabolite of intestinal bacteria, enhances sleep
Authors: Szentirmai Éva , Millican Nicklaus S. , Massie Ashley R. , Kapás Levente
Published: May 2019

Emerging evidence suggests that the intestinal microbiota is a source of sleep-promoting signals. Bacterial metabolites and components of the bacterial cell wall are likely to provide important links between the intestinal commensal flora and sleep-generating mechanisms in the brain. Butyrate is a short-chain fatty acid produced by the intestinal bacteria by the fermentation of nondigestible polysaccharides. We tested the hypothesis that butyrate may serve as a bacterial-derived sleep-promoting signal. Oral gavage administration of tributyrin, a butyrate pro-drug, elicited an almost 50% increase in non-rapid-eye movement sleep (NREMS) in mice for 4 hours after the treatment. Similarly, intraportal injection of butyrate led to prompt and robust increases in NREMS in rats. In the first 6 hours after the butyrate injection, NREMS increased by 70%. Both the oral and intraportal administration of butyrate led to a significant drop in body temperature. Systemic subcutaneous or intraperitoneal injection of butyrate did not have any significant effect on sleep or body temperature. The results suggest that the sleep-inducing effects of butyrate are mediated by a sensory mechanism located in the liver and/or in the portal vein wall. Hepatoportal butyrate-sensitive mechanisms may play a role in sleep modulation by the intestinal microbiota.
Unusual Conductance Fluctuations and Quantum Oscillation in Mesoscopic Topological Insulator PbBi4Te7
Authors: Mal Priyanath , Das Bipul , Lakhani Archana , Bera Ganesh , Turpu G. R. , Wu Jong-Ching , Tomy C. V. , Das Pradip
Published: May 2019

We present a detail study of Shubinikov-de-Haas (SdH) oscillations accompanied by conductance fluctuations in a mesoscopic topological insulator PbBi4Te7 device. From SdH oscillations, the evidence of Dirac fermions with π Berry phase is found and the experimentally determined two main Fermi wave vectors are correlated to two surface Dirac cones (buried one inside the other) of layered topological insulator PbBi4Te7. We have also found evidence of conductance fluctuations, the root mean square amplitude of which is much higher than the usual universal conductance fluctuations observed in nanometer size sample. Calculated autocorrelation functions indicate periodic unique fluctuations may be associated with the topological surface states in the compound.
The efficiency and safety of steroid addition to multimodal cocktail periarticular injection in knee joint arthroplasty: a meta-analysis of randomized controlled trials
Authors: Deng Zhenhan , Li Yusheng , Storm Garrett R. , Kotian Ronak Naveenchandra , Sun Xuying , Lei Guanghua , Gao Shanshan , Lu Wei
Published: May 2019

Steroids are frequently used for postoperative pain relief without definite evidence. This study was conducted to assess the pain management effect of the addition of steroids to a multimodal cocktail periarticular injection (MCPI) in patients undergoing knee arthroplasty and evaluate their safety. Pubmed, Embase, and Cochrane Library were searched through April, 2018. A total of 918 patients from ten randomized controlled trials (RCTs) were ultimately included. Compared with placebo groups, steroids application could effectively relieve pain on postoperative day (POD)1; decrease C-Reactive protein (CRP) level on POD3; improve range of motion (ROM) in postoperative 5 days; reduce morphine consumption, achieve earlier straight leg raising (SLR), and shorten the length of stay (LOS) in hospital. With regards to adverse effects, it did not increase the risk of postoperative infection, postoperative nausea and vomiting (PONV), or other complications. However, no significant difference in pain relief, ROM, or increased Knee Society Knee Function Scores were found during long-term follow up. Overall, this meta-analysis ensured the efficiency and safety of steroids with MCPI in knee arthroplasty patients during the early postoperative period.
Impacts of orography on large-scale atmospheric circulation
Authors: Sandu Irina , van Niekerk Annelize , Shepherd Theodore G. , Vosper Simon B. , Zadra Ayrton , Bacmeister Julio , Beljaars Anton , Brown Andrew R. , Dörnbrack Andreas , McFarlane Norman , Pithan Felix , Svensson Gunilla
Published: May 2019

Some of the largest and most persistent circulation errors in global numerical weather prediction and climate models are attributable to the inadequate representation of the impacts of orography on the atmospheric flow. Existing parametrization approaches attempting to account for unresolved orographic processes, such as turbulent form drag, low-level flow blocking or mountain waves, have been successful to some extent. They capture the basic impacts of the unresolved orography on atmospheric circulation in a qualitatively correct way and have led to significant progress in both numerical weather prediction and climate modelling. These approaches, however, have apparent limitations and inadequacies due to poor observational evidence, insufficient fundamental knowledge and an ambiguous separation between resolved and unresolved orographic scales and between different orographic processes. Numerical weather prediction and climate modelling has advanced to a stage where these inadequacies have become critical and hamper progress by limiting predictive skill on a wide range of spatial and temporal scales. More physically based approaches are needed to quantify the relative importance of apparently disparate orographic processes and to account for their combined effects in a rational and accurate way in numerical models. We argue that, thanks to recent advances, significant progress can be made by combining theoretical approaches with observations, inverse modelling techniques and high-resolution and idealized numerical simulations.
Wuchereria bancrofti filaria activates human dendritic cells and polarizes T helper 1 and regulatory T cells via toll-like receptor 4
Authors: Mukherjee Suprabhat , Karnam Anupama , Das Mrinmoy , Babu Santi P. Sinha , Bayry Jagadeesh
Published: May 2019

Interaction between innate immune cells and parasite plays a key role in the immunopathogenesis of lymphatic filariasis. Despite being professional antigen presenting cells critical for the pathogen recognition, processing and presenting the antigens for mounting T cell responses, the dendritic cell response and its role in initiating CD4+ T cell response to filaria, in particular Wuchereria bancrofti, the most prevalent microfilaria is still not clear. Herein, we demonstrate that a 70 kDa phosphorylcholine-binding W. bancrofti sheath antigen induces human dendritic cell maturation and secretion of several pro-inflammatory cytokines. Further, microfilarial sheath antigen-stimulated dendritic cells drive predominantly Th1 and regulatory T cell responses while Th17 and Th2 responses are marginal. Mechanistically, sheath antigen-induced dendritic cell maturation, and Th1 and regulatory T cell responses are mediated via toll-like receptor 4 signaling. Our data suggest that W. bancrofti sheath antigen exploits dendritic cells to mediate distinct CD4+ T cell responses and immunopathogenesis of lymphatic filariasis.
Treatment of volumetric muscle loss in mice using nanofibrillar scaffolds enhances vascular organization and integration
Authors: Nakayama Karina H. , Quarta Marco , Paine Patrick , Alcazar Cynthia , Karakikes Ioannis , Garcia Victor , Abilez Oscar J. , Calvo Nicholas S. , Simmons Chelsey S. , Rando Thomas A. , Huang Ngan F.
Published: May 2019

Traumatic skeletal muscle injuries cause irreversible tissue damage and impaired revascularization. Engineered muscle is promising for enhancing tissue revascularization and regeneration in injured muscle. Here we fabricated engineered skeletal muscle composed of myotubes interspersed with vascular endothelial cells using spatially patterned scaffolds that induce aligned cellular organization, and then assessed their therapeutic benefit for treatment of murine volumetric muscle loss. Murine skeletal myoblasts co-cultured with endothelial cells in aligned nanofibrillar scaffolds form endothelialized and aligned muscle with longer myotubes, more synchronized contractility, and more abundant secretion of angiogenic cytokines, compared to endothelialized engineered muscle formed from randomly-oriented scaffolds. Treatment of traumatically injured muscle with endothelialized and aligned skeletal muscle promotes the formation of highly organized myofibers and microvasculature, along with greater vascular perfusion, compared to treatment of muscle derived from randomly-oriented scaffolds. This work demonstrates the potential of endothelialized and aligned engineered skeletal muscle to promote vascular regeneration following transplantation.
Zinc–dysprosium functionalized amyloid fibrils
Authors: Sampani Stavroula I. , Al-Hilaly Youssra K. , Malik Sharali , Serpell Louise C. , Kostakis George E.
Published: May 2019

The heterometallic Zn2Dy2 entity bearing partially saturated metal centres covalently decorates a highly ordered amyloid fibril core and the functionalised assembly exhibits catalytic Lewis acid behaviour.
All-region-applicable, continuous power supply of graphene oxide composite
Authors: Huang Yaxin , Cheng Huhu , Yang Ce , Yao Houze , Li Chun , Qu Liangti
Published: May 2019

This study demonstrates an all-region-applicable moist-electric generator (MEG) based on a highly hydrophilic graphene oxide composite, delivering considerable electric energy over a wide temperature (−25 °C to 50 °C) and relative humidity range (RH, 5–95%).
Towards membrane-electrode assembly systems for CO2 reduction: a modeling study
Authors: Weng Lien-Chun , Bell Alexis T. , Weber Adam Z.
Published: May 2019

This work presents a multiphysics model simulating membrane-electrode assemblies for CO2 reduction.
Consequential life cycle assessment of carbon capture and utilization technologies within the chemical industry
Authors: Thonemann Nils , Pizzol Massimo
Published: May 2019

Carbon capture and utilization is recommendable within the chemical industry from an environmental perspective.
Stretchable elastomer composites with segregated filler networks: effect of carbon nanofiller dimensionality
Authors: Ke Kai , Sang Zhen , Manas-Zloczower Ica
Published: May 2019

Carbon nanofiller dimensionality affects the morphology of conductive networks built via an interface engineering strategy in composite materials, enabling the design of different flexible sensors and conductors for electronic applications.
Visible light induced aqueous RAFT polymerization using a supramolecular perylene diimide/cucurbit[7]uril complex
Authors: Yang Yongqi , An Zesheng
Published: May 2019

A water-soluble perylene diimide (PDI), in the presence of triethanolamine (TEOA), is used as a metal-free photocatalyst for aqueous reversible addition–fragmentation chain transfer (RAFT) polymerization under green light.
Rh(i)-Catalyzed intramolecular [2 + 2 + 1] cycloaddition of diynes with the N-terminal of the diazo group
Authors: Wang Bo , Wang Yuankai , Wang Zixuan , Wang Jianbo
Published: May 2019

A Rh(i) catalyzed [2 + 2 + 1] cycloaddition of intramolecular diynes and a diazo moiety has been reported, in which the dediazoniation does not occur and the terminal nitrogen of the diazo moiety serves as the N1 unit.
The enhancement of the D–A effect of an asymmetric Schiff base by introducing acetyl groups into diaminomaleonitrile: synthesis, red fluorescence and crystal structure
Authors: Wang Ke , Su Hao , Wang Pengfei , Wang Wenjie , Li Hui
Published: May 2019

An asymmetrical salen-type organic ligand was designed and synthesized by a new strategy developed using a precursor Ac-DMN, which is a diaminomaleonitrile (DMN) incorporated with an acetyl group.
Enhanced photocatalytic reduction of CO2 to CO over BiOBr assisted by phenolic resin-based activated carbon spheres
Authors: Liu Kangli , Zhang Xiaochao , Zhang Changming , Ren Guangmin , Zheng Zhanfeng , Lv Zhiping , Fan Caimei
Published: May 2019

Photocatalytic reduction of CO2 using solar energy to decrease CO2 emission is a promising clean renewable fuel production technology.
Bi2Te3 single crystals with high room-temperature thermoelectric performance enhanced by manipulating point defects based on first-principles calculation
Authors: Tang Chunmei , Huang Zhicheng , Pei Jun , Zhang Bo-Ping , Shang Peng-Peng , Shan Zhihang , Zhang Zhiyue , Gu Haiyun , Wen Kaibin
Published: May 2019

This study prepared Bi2Te3 single crystals and investigated the thermoelectric properties of Bi2Te3 based on the electronic structure and formation energy of point defects which are calculated by density functional theory.
Facile construction of magnetic core–shell covalent organic frameworks as efficient solid-phase extraction adsorbents for highly sensitive determination of sulfonamide residues against complex food sample matrices
Authors: Liu Jing-Min , Lv Shi-Wen , Yuan Xin-Yue , Liu Hui-Lin , Wang Shuo
Published: May 2019

Robust and efficient solid-phase extraction adsorbents based on magnetic core–shell covalent organic frameworks gave excellent analytical performance for determination of sulfonamide residues in food samples.
A comparative performance analysis of stand-alone, off-grid solar-powered sodium hypochlorite generators
Authors: Chinello E. , Modestino M. A. , Schüttauf J. W. , Coulot L. , Ackermann M. , Gerlich F. , Faes A. , Psaltis D. , Moser C.
Published: May 2019

Solar-powered electrochemical technologies can be employed to generate valuable chemical commodities on-site. We demonstrate solar-driven production of sodium hypochlorite, a widely employed water disinfection agent.
Vertical alignment of liquid crystals on plant-based vanillin derivative-substituted polystyrene films
Authors: Ju Changha , Park Chanhyuk , Kim Taehyung , Kang Hyo
Published: May 2019

Plant-based and renewable vanillin substituted polystyrene series are synthesized in order to investigate their liquid crystal alignment properties.
Supporting students’ conceptual understanding of kinetics using screencasts and simulations outside of the classroom
Authors: Sweeder Ryan D. , Herrington Deborah G. , VandenPlas Jessica R.
Published: May 2019

Simulations have changed chemistry education by allowing students to visualize the motion and interaction of particles underlying important chemical processes. With kinetics, such visualizations can illustrate how particles interact to yield successful reactions and how changes in concentration and temperature impact the number and success of individual collisions. This study examined how a simulation exploring particle collisions, or screencast employing the same simulation, used as an out-of-class introduction helped develop students’ conceptual understanding of kinetics. Students either manipulated the simulation themselves using guided instructions or watched a screencast in which an expert used the same simulation to complete an assignment. An iterative design approach and analysis of pretest and follow up questions suggests that students in both groups at two different institutions were able to achieve a common base level of success. Instructors can then build upon this common experience when instructing students on collision theory and kinetics. Eye-tracking studies indicate that the simulation and screencast groups engage with the curricular materials in different ways, which combined with student self-report data suggests that the screencast and simulation provide different levels of cognitive demand. This increased time on task suggests that the screencast may hold student interest longer than the simulation alone.
High-efficiency bubble transportation in an aqueous environment on a serial wedge-shaped wettability pattern
Authors: Song Jinlong , Liu Ziai , Wang Xuyue , Liu Hong , Lu Yao , Deng Xu , Carmalt Claire J. , Parkin Ivan P.
Published: May 2019

A serial wedge-shaped wettability pattern is designed to achieve long-distance spontaneous and directional pumpless transportation of subaqueous gas bubbles.
Ultrafine silver nanoparticles supported on a covalent carbazole framework as high-efficiency nanocatalysts for nitrophenol reduction
Authors: Gong Wei , Wu Qianqian , Jiang Guoxing , Li Guangji
Published: May 2019

A novel covalent micro/macro-porous polymer (CMP),CZ–TEB, is synthesized and then Ag NPs are immobilized on it, and the normalized rate constant (knor) of the Ag0@CZ–TEBcatalyzed reduction reaction of 4-NP to 4-AP reaches up to 21.49 mmol−1s−1.
Yolk–shell N-doped carbon coated FeS2nanocages as a high-performance anode for sodium-ion batteries
Authors: Zang Rui , Li Pengxin , Guo Xin , Man Zengming , Zhang Songtao , Wang Chengyin , Wang Guoxiu
Published: May 2019

Rationally designed yolk–shell structured N-doped carbon coated FeS2nanocages demonstrate superior high-rate and long-term cycling performance as anode materials for sodium-ion batteries.
Constructing peptide-based artificial hydrolases with customized selectivity
Authors: Zhu Mingjie , Wang Mengfan , Qi Wei , Su Rongxin , He Zhimin
Published: May 2019

The substrate selectivity of peptide-based artificial enzymes can be customized by combining molecularly imprinted polymers as binding sites with peptide nanofibers as catalytic moieties.
Highly efficient CsPbBr3 perovskite nanocrystals induced by structure transformation between CsPbBr3 and Cs4PbBr6 phases
Authors: Su Ying , Zeng Qinghui , Chen Xuejiao , Ye Weiguang , She Lushuang , Gao Ximing , Ren Zhongyuan , Li Xiaomeng
Published: May 2019

The structure transformation from CsPbBr3 to Cs4PbBr6 perovskite nanocrystals induced fluorescence enhancement was detected and applied in the LED devices.
Bi‐level network reconfiguration model to improve the resilience of distribution systems against extreme weather events
Authors: Khomami Masoud Sadeghi , Jalilpoor Kamran , Kenari Meghdad Tourandaz , Sepasian Mohammad Sadegh
Published: May 2019

When a natural disaster occurs in a distribution network, a widespread power interruption may occur for a few days or weeks. This study presents a bi‐level optimisation‐based model for reconfiguration of the distribution network to improve the resilience of electricity distribution network against severe weather events such as storm and hurricane with the aim of minimising the cost of load outage. To achieve this, a model is first presented for evaluating the vulnerability of distribution network poles to estimate the damages imposed by the threat. Then, in the first level, according to the forecasting of possible failed lines and based on the predicted wind speed before the storm, a network reconfiguration strategy is employed to minimise the expected cost of load outage. In the second level, a new reconfiguration is carried out to restore the system loads and minimise the cost of load outage after the storm. The proposed model is then applied to a standard 33‐bus radial distribution system using the GAMS software. The simulation results demonstrate the effectiveness of the proposed model in increasing network resilience and highlight the importance of network reconfiguration in the face of extreme natural disasters.
Short‐term passenger flow forecast of urban rail transit based on GPR and KRR
Authors: Guo Zhiqiang , Zhao Xin , Chen Yaxin , Wu Wei , Yang Jie
Published: May 2019

Short‐term passenger flow forecasting can help the operation management department to adjust the related work. At the same time, it can also guide the traveller to choose a reasonable travel time and route, which plays an important role in promoting the development and construction of the city. In this study, the authors propose a hybrid prediction model based on kernel ridge regression (KRR) and Gaussian process regression (GPR) to predict the short‐term passenger flow of urban rail transit, and verify it on the Automatic Fare Collection System (AFC) dataset. Firstly, they utilise the stability feature selection algorithm to control the error of finite samples and use a GPR algorithm to obtain the original result. Then, they introduce stacked auto‐encoder network to construct a feature extraction model, and apply k ‐means method to divide the stations into different types, defining as a site feature. Furthermore, they choose KRR algorithm with the combination of GPR prediction result and the holiday information, the station category information mentioned above, achieving the final prediction. The algorithm proposed in this study effectively improves the prediction accuracy and ensures time efficiency, and all the indicators are better than the existing algorithms.
Hybrid virtual polarimetric massive MIMO measurements at 1.35 GHz
Authors: Challita Frédéric , Laly Pierre , Liénard Martine , Tanghe Emmeric , Joseph Wout , Gaillot Davy P.
Published: May 2019

The polarimetric massive multiple‐input multiple‐output (MIMO) radio channel of an indoor line‐of‐sight scenario is investigated at 1.35 GHz using a real‐time radio channel sounder. The 8 × 12 massive MIMO transmitter is constructed using a hybrid architecture including a vertical uniform linear array translated at different horizontal positions forming a virtual, yet realistic, uniform rectangular array. The performance of the system is evaluated with six users distributed in the room for different polarisation schemes and receiver orientations using propagation channel‐based metrics (such as receiver spatial correlation and Rician factor) and system‐oriented metrics such as sum‐rate capacity and signal to interference and noise ratio. The results show a clear dependence of the performance to the polarisation schemes and receiver orientation and showing that when facing the array, cross‐polarisation can be very beneficial. Furthermore, it is concluded that the additional degree of freedom brought by the polarisation diversity can contribute to improve spectral efficiency (∼20% depending on the configuration), paving the way for further capacity enhancements in massive MIMO systems. It was also found that the receiver spatial correlation can be modelled using a Burr distribution.
Optically controlled millimetre‐wave switch with stepped‐impedance lines
Authors: Zhang Yutian , Pang Alexander Weiran , Cryan Martin James
Published: May 2019

A photoconductive grounded coplanar waveguide (GCPW) millimetre‐wave switch controlled by a single infrared light‐emitting diode is presented. By converting a straight GCPW transmission line into an alternating stepped‐impedance line structure, the proposed device shows an on‐state insertion loss of <2.9 dB and an off‐state isolation of more than 15 dB over a wide‐frequency range of 12–30 GHz, with a particularly good radio‐frequency performance in the K‐band (18–27 GHz). The required optical power and electrical power of the switch are only 199 and 364 mW, respectively. This device also demonstrates an absorptive characteristic with a low reflection coefficient of <−13.5 dB within this frequency range for both the on and off states. In addition, by employing through‐holes for illumination of a silicon superstrate, the proposed device can be fabricated with rapid and low‐cost laser etching and can be easily integrated with other microwave and millimetre‐wave circuits.
Bidirectional DC–DC converter with high gain based on impedance source
Authors: Ortega Manuel , Ortega María Victoria , Jurado Francisco , Carpio José , Vera David
Published: May 2019

This study presents a new bidirectional DC–DC converter with high gains, based on impedance source. The design of the impedance network has been studied in step‐up and step‐down modes. The most significant innovations of the proposed converter are the linearity of the high gains in step‐up and step‐down modes with respect to the cycle variations and a full use of the duty cycle, very few passive and semiconductor elements are needed to implement the converter. The switching techniques are very simple, since only the switching of a single transistor in each mode is required. To improve efficiency, the cores of the inductors have been constructed with nanocrystalline material and the resistance of Z‐red has been reduced as much as possible. Finally, a laboratory prototype has been implemented.
Multidirectional development of IGBTs and diodes: low loss and tough but gentle (user‐friendly) power devices
Authors: Honda Shigeto , Minato Tadaharu , Shimizu Kazuhiro , Furukawa Akihiko , Terasaki Yoshiaki , Hatade Kazunari , Takata Yoshifumi
Published: May 2019

From the power loss reduction and safety operation points of view, the direction of power device developments is simply one‐way. However, from the application point of view, the direction is wide‐ranging. There are a variety of requirements to be considered, such as switching waveforms, operational environments including not only the temperature range but also the combination of the humidity, the cosmic ray endurance, the package compactness and so on. In this study, several efforts are explained as the latest technologies.
Hybrid single and double‐voltage vector‐based model predictive common‐mode voltage reduction method for 2‐level voltage source inverters
Authors: Guo Leilei , Jin Yuxiang , Cao Lingzhi , Dai Linwang , Luo Kui
Published: May 2019

To reduce the common‐mode voltage (CMV) as well as the current total harmonic distortions (THDs) of 2‐level voltage source inverters (2L‐VSIs), a hybrid single and double‐voltage vector (VV)‐based model predictive control (MPC) method is proposed. Firstly, a two non‐zero VV‐based MPC strategy is proposed to reduce the CMV as well as the current THDs. Secondly, the influences of the dead time on this method are analysed in detail, and an improved VV preselection method is further proposed to remove the dead time effects. Thirdly, considering the impacts of the control delay and the current ripples, a new current sector division method is presented, based on which a hybrid single and double‐VV‐based MPC strategy is finally proposed. Furthermore, the current variation per control period under the action of different VVs is also analysed in‐depth in this study to lay a solid theoretical foundation for dividing the current sector more properly. Both the simulation and experimental studies are carried out to verify the effectiveness of the proposed method.
Implementation of a new high‐power current‐source single‐stage PV grid‐connected system with reactive power compensation
Authors: Wu Haitao , Liu Yonghe , Wang Zhihe
Published: May 2019

In view of the shortcoming of voltage source converter in the application of high‐power photovoltaic (PV) grid‐connected system, this study designs a new single‐stage current source PV grid‐connected system based on dc current reinjection conversion. The system can freely control the dc current in a wide range, so only one stage of conversion is needed to achieve wide range control of the dc side maximum power point tracking. The amplitude and phase angle of the ac output current can be freely regulated, so it is able to realise grid‐connected power generation under unit power factor and supply a certain amount of reactive power according to the control order while grid‐connected power generation. Meanwhile, the new current source converter topology eliminates the ac capacitors which are arranged between the converter and the power grid, and gets approximately sinusoidal ac currents without setting filters. This study describes the circuit structure and control of the PV grid‐connected system, and builds an experimental prototype. The simulation and experimental results will be shown to demonstrate the feasibility of the converter topology, and the effectiveness of the control strategy.
QSO2 outflow characterization using data obtained with OSIRIS at the Gran Telescopio Canarias
Authors: Bellocchi Enrica , Villar Martín Montserrat , Cabrera–Lavers Antonio , Emonts Bjorn
Published: May 2019

Context. Ionized outflows are ubiquitous in non-radio-loud obscured quasars (QSO2s) at different redshifts. However, the actual size of the outflows and their efficiency for gas ejection and star formation truncation are controversial. Large-scale (exceeding several kiloparsec) extended radio structures might be necessary to identify (even to trigger) outflow signatures across such large spatial scales.

Aims. We search for large-scale ionized outflows associated with six optically selected QSO2 (five non-radio-loud and one radio-loud) at z ∼ 0.2−0.5, targeting objects with extended radio structures. We also investigate the dynamical state of the QSO2 host galaxies.

Methods. We obtained data with the optical imager and long-slit spectrograph (OSIRIS) mounted on the 10.4m Gran Telescopio Canarias Spanish telescope (GTC) for these six QSO2 with the slit located along the radio axis. We traced the gas kinematics with the [OIII]λλ4959,5007 lines to investigate ionized outflows and characterize the dynamical state of the host galaxies. This second study was complemented with previously published spectroscopic data obtained with the multimode focal reducer and low dispersion spectrograph (FORS2) mounted on the Very Large Telescope (VLT) of 13 more QSO2 at similar z.

Results. We identify ionized outflows in four out of the six QSO2 observed with the GTC. The outflows are spatially unresolved in two QSO2 and compact in a third (radial size of R = 0.8 ± 0.3 kpc). Of particular interest is the radio-quiet QSO2 SDSS 0741+3020 at z = 0.47. It is associated with a giant ∼112 kpc nebula. An ionized outflow probably induced by the radio structures has been detected along the axis defined by the central ∼1″ radio structure, extending up to at least ∼4 kpc from the active galactic nucleus (AGN). Turbulent gas (σ ∼ 130 km s−1) has also been detected across the giant gas nebula up to ∼40 kpc from the AGN. This turbulence may have been induced by outflows triggered by the interaction between a so-far undetected large-scale radio source and the nebula. Regarding the dynamical state of the host galaxies, we find that the majority of the QSO2 show v/σ <  1, implying that they are dominated by random motions (so-called dispersion-dominated systems). Most (17 of 19) fall in the area of the E/S0 galaxies in the dynamical diagram v/σ versus σ. None are consistent with spiral or disk galaxies.
The Study of Position Accuracy Using Precise Point Positioning (PPP) In Perspective of Indonesian National Standard of Horizontal Reference Network
Authors: Azis Rasyad A. , Suhandri Hendy F. , Wijaya Dudy D.
Published: May 2019

Precise point positioning is a GNSS based positioning method that is known to regaining more precise information about major systematical errors in its functional model. This method is seen as an advanced version of the conventional absolute positioning method that is able to offer higher accuracy of the estimate parameter. Contrarily, the relative positioning method is able to achieve high precise of the estimated parameters by using two or more receiver. Consequently, it utilizes more resources in performing observation. Hence, this contribution attempts to explore some considerable aspects that can make the PPP method has a comparable precision of the National Standard of Horizontal Reference Network (SNI JKH). Based on the experiments, with data rate of 0.03 Hz for GPS and GLONASS observation shown that result of the PPP method is comparable to the relative method, whenever the observation is performed in minimum duration of six hours. Moreover, the 3th order of accuracy can be achieved after a demanding observation period, depends on processing strategy.
Multi-Thread Based Design of Navigation Algorithm Module in Multi Radio Integrated Navigation System M&S Software
Authors: Son Jae Hoon , Kim Heyone , Oh Sang Heon , So Hyoungmin , Hwang Dong-Hwan
Published: May 2019

A multi-thread based navigation algorithm module is designed in a multi radio integrated navigation system modeling and simulation software in order to efficiently use resources in the software platform of the modeling and simulation software. By adopting the multi-thread architecture, features of navigation algorithms and concurrency of the algorisms can be easily included in the navigation algorithm module. In order to show the usefulness of the multi thread based navigation algorithm module design, a navigation algorithm module in the multi-radio integrated navigation system for GPS, KNSS, Loran-C, eLoran and DME/VOR is implemented in C++ under the Windows operating system. The implementation results show that the thread based design can be useful in the development of multi radio integrated navigation systems.
Integration of Inertial Navigation System with EM-log Using H-infinity Filter
Authors: Cha Jaehyuck , Ju Hojin , Park Chan Gook , Yoo Kijeong , Park Chanju
Published: May 2019

This paper presents the integration of inertial navigation system (INS) with electromagnetic-log (EM-log) as an underwater navigation system using H-infinity filter for robustness from the uncertainty of the sea current model. In underwater environments, the electromagnetic signals are attenuated rapidly, so that the global navigation satellite system is not available in general. Thus, INS is usually chosen for underwater navigation, and other aiding sensors are also used to complement its accumulative errors, one of which is EM-log. Since an EM-log provides the relative velocity to seawater, the integrated navigation cannot be performed accurately unless the sea current speed is compensated properly. Generally, the INS and EM-log can be integrated using extended Kalman filter (EKF). However, EKF guarantees its performance when the stochastic properties of the system’s process and measurement noises are perfectly known. In other words, in the presence of sea current modelling errors, the integration using the EKF is not expected to show good performance. On the other hand, H-infinity filter is a robust filter which can tolerate such uncertainties. In this paper, the integration of INS and EM-log using H-infinity filter is studied. The performance is compared with that of the EKF case by proper computer simulation.
Analyze Angle of the Camera Payload LSU-02 in Mission of Aerial Photo
Authors: Sunar  , Budiyanta Ari Sugeng , Estu Broto Prasepvianto , Utama Agus Bayu
Published: May 2019

In carrying out its mission, LAPAN Surveillance UAV version 2 (LSU-02) was equipped with a camera payload sensor mounted on a gimbal system. When taking upright aerial photos according to photogrammetric requirements, the axis of the aerial camera must be aligned with the direction of gravity with a slope tolerance less than 3 degrees (<3°), so that the shooting results meet the map to the desired standard. The camera payload was equipped with a 3-axis gimbal system which pitch and roll directions installed by the gyro sensor to measure the camera's tilt angle. Gimbal camera payload with dimensions (160×170×155) mm are designed to be installed on a casing (190×190×180) mm according to the available space in the LSU-02 payload space, which was the length x width x height (190×190×180) mm. Testing was done by flying LSU-02 on Rumpin and Pamengpeuk runway. From the test results, it was obtained the deviation of roll and pitch angle less than 3degree, which the gimbal angle oscillation when the payload camera shooting was only ± 1 degree with the respon time until it reaches a stable condition of approximately 35 to 55 seconds, and the offset value for roll and pitch approximately -1 degree, which it has met the standard for making aerial photo maps according to photogrammetric requirements.
GNSS RTK Application to Determine Coastline Case Study at Northen Area of Sulawesi and Gorontalo
Authors: Nugraha Wahyudi , Parapat Andri Daniel , Arum Dewi Sekar , Istighfarini Fatichatus
Published: May 2019

Article 12 of Indonesia Government Regulation No.4-year 2011 about Geospatial Information [5], coastline is an element of base map. Article 13 subsection 1 states that the boundary form between the land and the ocean were affected by the tides. In subsection 2, coastline is divided into three types, namely lowest, highest, and mean sea level tides. Studies about coastline is important to support many maritime activities such as to determine administrative area (such as province, etc.), determine the length of coastline, coastal and marine management, also inland and marine spatial planning. Due to the importance of coastline, data with good accuracy is needed. Coastline mapping technology has developed rapidly. Previous method of coastline mapping is to trace marine debris carried by wave to the coast. At present time, because of needs of coastline data with higher accuracy and in the bigger scales, the GNSS RTK technology is starting to be used. GNSS technology generated coordinates and elevation and use tides values as reference datum. After the above, Digital Elevation Model generated from those points are combined with bathymetry and land elevation data resulting three types of coastline in accordance with the Indonesia Government Regulation about Geospatial Information Article 13 Subsection 2.
Accuracy Analysis of GNSS (GPS, GLONASS and BEIDOU) Obsevation For Positioning
Authors: Khomsin  , Mutiara Anjasmara Ira , Guruh Pratomo Danar , Ristanto Wahyu
Published: May 2019

Global Navigation Satellite System called GNSS is a term used for the entire global navigation that already operate or are in the planning for the future. Some of the satellite that can be used are GPS (Global Positioning System) operated by USA, GLONASS (Global Navigation Satellite System) operated by Rusia and BeiDou/Compass operated by China. Many errors and biases that occur when measuring with GNSS in the field. Theoritically, there are some errors and biases that can be eliminated or subtracted by strength of satellite geometric. One factor to get a good satellite geometric is to increase the number of satellites received by receiver. In general, the more number of satellites received, the better the geometric satellites received by receivers. The development of receiver technology is currently able to capture GPS, GLONASS and BeiDou signals at one time. Thus the receiver can receive many satellites and finally the shape of geometric satellite becomes better. HiTarget V30 is one of the latest GNSS technology on the market today. This receiver is capable of receiving GPS signals, GLONASS and BeiDou at one time of observation. This research will compare the accuracy of positioning using GPS, GLONASS and BeiDou satellite.