bluuebunny/crossref_metadata_2025 huggingface dataset:
Accurate Laboratory Measurement of the O2 Collision‐Induced Absorption Band Near 1.27 μm
Authors: Mondelain D. , Kassi S. , Campargue A.
Published: December 2018

The atmospheric band of O2 near 1.27 μm plays an important role in determining the air mass from ground or spaceborne atmospheric spectra. This band consists of narrow absorption lines of the
transitions superimposed to a much broader collision‐induced absorption (CIA) structure. Very accurate CIA binary coefficients,
,
, and
, are determined by highly sensitive cavity ring down spectroscopy from low density spectra (0.36 to 0.85 amagat) of pure oxygen and an O2/N2 mixture (20.96%/79.04%) at room temperature over the 7,513–8,466‐cm−1 region. Two cavity ring down spectrometers involving 12 distributed feedback lasers and two external cavity diode lasers were used below and above 7,920 cm−1, respectively. The measurements performed at different densities show a percent level consistency. This accuracy results from (i) a high baseline stability of the spectra, (ii) an accurate determination of the baseline using argon spectra recorded for the same densities, and (iii) a reliable removal of the local contribution of the absorption lines made easier thanks to subatmospheric pressure recordings. The retrieved binary coefficients are compared to the experimental data included in HITRAN2016 database (Maté et al., 1999, https://doi.org/10.1029/1999JD900824), to the dataset used for Total Carbon Column Observing Network spectra as well as to recent ab initio calculations. Although more accurate, the binary coefficients reported here are found in agreement with the Maté et al. measurements using high pressure Fourier transform spectroscopy. The derived value of the integrated CIA band intensity
= 1.31(3) × 10−4 cm−2 amagat−2 exceeds the corresponding Fourier transform spectroscopy value by about 3%.
Global Pyrogenic Carbon Production During Recent Decades Has Created the Potential for a Large, Long‐Term Sink of Atmospheric CO2
Authors: Wei Xinyuan , Hayes Daniel J. , Fraver Shawn , Chen Guangsheng
Published: December 2018

Fires play an important role in the terrestrial biosphere carbon cycle, not only through direct carbon release but also contributing to a potential long‐term storage as pyrogenic carbon (PyC). PyC is formed through fires, and, because it may resist further biological and chemical degradation, is more stable in soil and sediment than original biomass. At the global scale, contributions of fires to both atmospheric CO2emissions and PyC accumulation are potentially large but difficult to estimate. Our analysis was based on existing simulation results from two different modeling approaches (Global Fire Emissions Database version 4 [GFED4s] and Terrestrial Ecosystem Model version 6 [TEM6]) that used global area burned data to provide recent, retrospective estimates of CO2emissions from vegetation combustion, together with published, biome‐ and continental‐scale conversion ratios that relate CO2emissions to PyC production (PyC/CO2) during combustion. The estimates of global CO2emissions from fires differed substantially between the two models' results. GFED4s estimated 2,041 Tg C/year during the 2000–2016 time period, whereas the TEM6 estimate was considerably lower at 643 Tg C/year from 2000 to 2010. Global PyC production estimates from fires were 153.4 ± 18.7 and 49.5 ± 4.9 Tg C/year based on the emission estimates from GFED4s and TEM6, respectively. Our results suggest that African tropical savanna fires produced the largest amount of CO2emissions and PyC among global biomes, the most significant interannual variations in CO2emissions and PyC production were found in tropical forests, and the magnitude of PyC produced by fires each year represented a potentially significant long‐term sink of atmospheric CO2.
Impact of an Extreme Storm Event on River Corridor Bank Erosion and Phosphorus Mobilization in a Mountainous Watershed in the Northeastern United States
Authors: Ross Donald S. , Wemple Beverley C. , Willson Lindsay J. , Balling Courtney M. , Underwood Kristen L. , Hamshaw Scott D.
Published: December 2018

Movement of sediment, and associated phosphorus, from stream banks to freshwater lakes is predicted to increase with greater frequency of extreme precipitation events. This higher phosphorus load may accelerate harmful algal blooms in affected water bodies, such as Lake Champlain in Vermont, New York, and Québec. In the Mad River, a subwatershed in central Vermont's Lake Champlain Basin, extreme flooding from Tropical Storm Irene in 2011 caused extensive erosion. We measured stream channel change along the main stem between 2008 and 2011 by digitizing available prestorm and poststorm aerial imagery. Soils were sampled post Irene at six active stream erosion sites, using an experimental design to measure differences in soil texture and phosphorus both with depth (90 cm) and distance from the stream. In addition to total phosphorus (TP), we determined bioavailable (soil test) phosphorus (STP) and the degree of phosphorus saturation (DPS). The six sites represented a 0.87‐km length of stream bank that contributed an estimated 17.6 × 103 Mg of sediment and 15.8 Mg of TP, roughly the same as average annual watershed export estimates. At four sites, the STP and DPS were low and suggested little potential for short‐term phosphorus release. At two agricultural sites where the lateral extent of erosion was high, imagery showed a clear loss of well‐established riparian buffer. Present‐day near‐stream soils were elevated in STP and DPS. An increase in these extreme events will clearly increase sediment loads. There will also be increasing concentration of sediment phosphorus if stream banks continue to erode into actively managed agricultural fields.
Effects of Cyanobacterial Soil Crusts on Surface Roughness and Splash Erosion
Authors: Bullard Joanna E. , Ockelford Annie , Strong Craig , Aubault Helene
Published: December 2018

Soil surface roughness (SSR) modifies interactions and feedback processes between terrestrial and atmospheric systems driven by both the abiotic and biotic components of soils. This paper compares SSR response to a low‐intensity multiday rainfall event for soils with and without early successional stage cyanobacteria‐dominated biological soil crusts (CBCs). A rainfall simulator was used to apply 2, 5, and 2 mm of rain separated by a 24‐hr period over 3 days at an intensity of 60 mm/hr. Changes in SSR were quantified using geostatistically derived indicators calculated from semivariogram analysis of high‐resolution laser scans. The CBCs were stronger and splash erosion substantially less than from the physical soil crusts. Prior to rainfall treatment, soils with CBCs had greater SSR than those without. The rainfall treatments caused the physical crusted soils to increase SSR and spatial patterning due to the translocation of particles, soil loss, and the development of raindrop impact craters. Rainfall caused swelling of cyanobacterial filaments but only a slight increase in SSR, and raindrop impact cratering and splash loss were low on the soils with CBCs. There is no relationship between random roughness and splash erosion, but an increase in splash loss was associated with an increase in topographic roughness and small‐scale spatial patterning. A comparison of this study with other research indicates that for rainfall events up to 100 mm, the effectiveness of CBCs in reducing soil loss is >80% regardless of the rainfall amount and intensity, which highlights their importance for landscape stabilization.
The selective pressures on the microbial community in a metal-contaminated aquifer
Authors: Carlson Hans K , Price Morgan N , Callaghan Mark , Aaring Alex , Chakraborty Romy , Liu Hualan , Kuehl Jennifer V , Arkin Adam P , Deutschbauer Adam M
Published: December 2018

In many environments, toxic compounds restrict which microorganisms persist. However, in complex mixtures of inhibitory compounds, it is challenging to determine which specific compounds cause changes in abundance and prevent some microorganisms from growing. We focused on a contaminated aquifer in Oak Ridge, Tennessee, USA that has large gradients of pH and widely varying concentrations of uranium, nitrate, and many other inorganic ions. In the most contaminated wells, the microbial community is enriched in the Rhodanobacter genus. Rhodanobacter abundance is positively correlated with low pH and high concentrations of uranium and 13 other ions and we sought to determine which of these ions are selective pressures that favor the growth of Rhodanobacter over other taxa. Of these ions, low pH and high UO22+, Mn2+, Al3+, Cd2+, Zn2+, Co2+, and Ni2+ are both (a) selectively inhibitory of a Pseudomonas isolate from an uncontaminated well vs. a Rhodanobacter isolate from a contaminated well, and (b) reach toxic concentrations (for the Pseudomonas isolate) in the Rhodanobacter-dominated wells. We used mixtures of ions to simulate the groundwater conditions in the most contaminated wells and verified that few isolates aside from Rhodanobacter can tolerate these eight ions. These results clarify which ions are likely causal factors that impact the microbial community at this field site and are not merely correlated with taxonomic shifts. Furthermore, our general high-throughput approach can be applied to other environments, isolates, and conditions to systematically help identify selective pressures on microbial communities.
Ultrastructural pathology of oligodendrocytes adjacent to microglia in prefrontal white matter in schizophrenia
Authors: Uranova Natalya A. , Vikhreva Olga V. , Rakhmanova Valentina I. , Orlovskaya Diana D.
Published: December 2018

Microglial activation has been proposed to be involved in the pathophysiology of schizophrenia (SCZ). We hypothesized that dystrophic alterations of oligodendrocytes previously reported in the prefrontal white matter in SCZ might be associated with microglial activation in the acute state of SCZ. White matter of the prefrontal cortex (BA10) was studied in post-mortem brain tissue from 21 SCZ cases and 20 normal controls. The SCZ group included 12 subjects with predominantly positive symptoms and 9 subjects with predominantly negative symptoms. Electron microscopy was applied to estimate cell density, size, volume fraction (Vv) and the number (N) of organelles in oligodendrocytes adjacent to microglia and in oligodendrocytes adjacent to myelin, neurons and capillaries and not adjacent to microglia. Cell density of oligodendrocytes was not changed in the SCZ group as compared to controls. Vv and N of mitochondria were significantly decreased, while Vv of vacuoles of endoplasmic reticulum and lipofuscin granules were significantly increased in oligodendrocytes adjacent to either microglia or myelin in the SCZ group and in patients displaying predominantly positive symptoms as compared to the control group. There were no significant differences between oligodendrocytes adjacent to microglia and to myelin. Vv and N of lipofuscin were also increased in peri-capillary oligodendrocytes. There was no effect of clinical subgroups on the parameters of peri-capillary and peri-neuronal oligodendrocytes. Though many ameboid and dystrophic microglia adjacent to oligodendrocytes were found in the SCZ samples, we provide no quantitative evidence that oligodendrocyte dystrophy is associated with microglial activation in white matter in SCZ.
Baculovirus as an efficient vector for gene delivery into mosquitoes
Authors: Naik Nenavath Gopal , Lo Yu-Wen , Wu Tzong-Yuan , Lin Chang-Chi , Kuo Szu-Cheng , Chao Yu-Chan
Published: December 2018

Efficient gene delivery technologies play an essential role in the gene functional analyses that are necessary for basic and applied researches. Mosquitoes are ubiquitous insects, responsible for transmitting many deadly arboviruses causing millions of human deaths every year. The lack of efficient and flexible gene delivery strategies in mosquitoes are among the major hurdles for the study of mosquito biology and mosquito-pathogen interactions. We found thatAutographa californicamultiple nucleopolyhedrovirus (AcMNPV), the type baculovirus species, can efficiently transduce mosquito cells without viral propagation, allowing high level gene expression upon inducement by suitable promoters without obvious negative effects on cell propagation and viability. AcMNPV transduces into several mosquito cell types, efficiently than in commonly used mammalian cell lines and classical plasmid DNA transfection approaches. We demonstrated the application of this system by expressing influenza virus neuraminidase (NA) into mosquito hosts. Moreover, AcMNPV can transduce both larvae and adults of essentially all blood-sucking mosquito genera, resulting in bright fluorescence in insect bodies with little or no tissue barriers. Our experiments establish baculovirus as a convenient and powerful gene delivery vectorin vitroandin vivothat will greatly benefit research into mosquito gene regulation, development and the study of mosquito-borne viruses.
Quantum Renormalization of Spin Squeezing in Spin Chains
Authors: Balazadeh Leila , Najarbashi Ghader , Tavana Ali
Published: December 2018

By employing quantum renormalization group (QRG) method, we investigate quantum phase transitions (QPT) in the Ising transverse field (ITF) model and in the XXZ Heisenberg model, with and without Dzyaloshinskii Moriya (DM) interaction, on a periodic chain of N lattice sites. We adopt a new approach called spin squeezing as an indicator of QPT. Spin squeezing, through analytical expression of a spin squeezing parameter, is calculated after each step of QRG. As the scale of the system becomes larger, (after many QRG steps), the ground state (GS) spin squeezing parameters show an abrupt change at a quantum critical point (QCP). Moreover, in all of the studied models, the first derivative of the spin squeezing parameter with respect to the control parameter is discontinuous, which is a signature of QPT. The spin squeezing parameters develop their saturated values after enough QRG iterations. The divergence exponent of the first derivative of the spin squeezing parameter in the near vicinity of the QCP is associated with the critical exponent of the correlation length.
microRNA-29b mediates fibrotic induction of human xylosyltransferase-I in human dermal fibroblasts via the Sp1 pathway
Authors: Riedel Lara , Fischer Bastian , Ly Thanh-Diep , Hendig Doris , Kuhn Joachim , Knabbe Cornelius , Faust Isabel
Published: December 2018

Diminished microRNA-29b levels have recently been revealed to provoke increased expression and accumulation of extracellular matrix molecules, such as collagens in fibrotic remodeling. Subsequently, the aim of this study was to find out whether microRNA-29b might also regulate human xylosyltransferase (XT)-I expression. XT-I has been characterized previously as a fibrosis biomarker catalyzing the key step of proteoglycan biosynthesis. While we demonstrate that XYLT1 is neither a target of microRNA-29b identified in silico nor a direct 3′ untranslated region binding partner of microRNA-29b, transfection of normal human dermal fibroblasts with microRNA-29b inhibitor strongly increased XYLT1 mRNA expression and XT activity. Combined results of the target prediction analysis and additional transfection experiments pointed out that microRNA-29b exerts indirect influence on XT-I by targeting the transcription factor specificity protein 1 (Sp1). We could confirm our hypothesis due to the decrease in XYLT1 promoter activity after Sp1 binding site mutation and the approval of occupancy of these binding sites by Sp1 in vitro. Taken together, a hitherto unidentified pathway of XT-I regulation via microRNA-29b/Sp1 was determined in this study. Our observations will facilitate the understanding of complex molecular fibrotic pathways and provide new opportunities to investigate microRNA-based antifibrotic tools.
The crystal structure of a tetrahydrofolate-bound dihydrofolate reductase reveals the origin of slow product release
Authors: Cao Hongnan , Gao Mu , Zhou Hongyi , Skolnick Jeffrey
Published: December 2018

Dihydrofolate reductase (DHFR) catalyzes the stereospecific reduction of 7,8-dihydrofolate (FH2) to (6s)-5,6,7,8-tetrahydrofolate (FH4) via hydride transfer from NADPH. The consensus Escherichia coli DHFR mechanism involves conformational changes between closed and occluded states occurring during the rate-limiting product release step. Although the Protein Data Bank (PDB) contains over 250 DHFR structures, the FH4 complex structure responsible for rate-limiting product release is unknown. We report to our knowledge the first crystal structure of an E. coli. DHFR:FH4 complex at 1.03 Å resolution showing distinct stabilizing interactions absent in FH2 or related (6R)-5,10-dideaza-FH4 complexes. We discover the time course of decay of the co-purified endogenous FH4 during crystal growth, with conversion from FH4 to FH2 occurring in 2–3 days. We also determine another occluded complex structure of E. coli DHFR with a slow-onset nanomolar inhibitor that contrasts with the methotrexate complex, suggesting a plausible strategy for designing DHFR antibiotics by targeting FH4 product conformations.
Heparin-reduced graphene oxide nanocomposites for curcumin delivery: in vitro, in vivo and molecular dynamics simulation study
Authors: Shi Xiaoqun , Wang Yang , Sun Haiyan , Chen Yujuan , Zhang Xingzhen , Xu Jiangkang , Zhai Guangxi
Published: December 2018

We fabricated novel rGO-based nanocomposites and analyzed their interaction with drug and proteins via a molecular dynamics study.
Ultrafast Na intercalation chemistry of Na2Ti3/2Mn1/2(PO4)3 nanodots planted in a carbon matrix as a low cost anode for aqueous sodium-ion batteries
Authors: Lei Ping , Liu Kelu , Wan Xin , Luo Dongxue , Xiang Xingde
Published: December 2018

Na2Ti3/2Mn1/2(PO4)3 nanodots planted in a carbon matrix were reported as a novel anode for aqueous sodium-ion batteries, showing ultrafast Na-intercalation chemistry.
Scalable preparation and property investigation of a cis-cyclobutane-1,2-dicarboxylic acid from β-trans-cinnamic acid
Authors: Amjaour Houssein , Wang Zhihan , Mabin Micah , Puttkammer Jenna , Busch Sullivan , Chu Qianli R.
Published: December 2018

Scalable synthesis of CBDA-4, a thermocleavable diacid building block, was accomplished by capturing and photodimerizing a metastable crystalline solid of trans-cinnamic acid.
Controlled diazonium electrografting driven by overpotential reduction: a general strategy to prepare ultrathin layers
Authors: Pichereau Laure , López Isidoro , Cesbron Marius , Dabos-Seignon Sylvie , Gautier Christelle , Breton Tony
Published: December 2018

A global and extremely simple strategy to prepare a covalently attached monolayered organic film on the carbon surface is presented.
Rhodium(iii)-catalyzed sulfonamide directed ortho C–H carbenoid functionalization via metal carbene migratory insertion
Authors: Dong Yi , Chen Jiajing , Xu Heng
Published: December 2018

A rhodium(iii)-catalyzed sulfonamide directed ortho C–H carbenoid functionalization has been developed with good yields.
In situ visualization of the quasi-periodic crystal growth interface fluctuation by growth interface electromotive force spectrum in a Czochralski system
Authors: Zhu Yunzhong , Lin Shaopeng , Liu Zhihua , Wang Wenjia , Ma Decai , Wang Biao
Published: December 2018

Growth interface electromotive force (GEMF) visualizes the real-time states of crystal growth rate, supercooling degree and rotation temperature fluctuations.
Synthesis, characterization and biological investigation of platinum(ii) complexes with asparagusic acid derivatives as ligands
Authors: Hildebrandt Jana , Trautwein Ralf , Kritsch Daniel , Häfner Norman , Görls Helmar , Dürst Matthias , Runnebaum Ingo B. , Weigand Wolfgang
Published: December 2018

Novel platinum complexes with another mode of action may solve the major issue of resistance.
Synthesis and characterization of cyclohexane-1R,2R-diamine-based Pt(iv) dicarboxylato anticancer prodrugs: their selective activity against human colon cancer cell lines
Authors: Gabano E. , Ravera M. , Perin E. , Zanellato I. , Rangone B. , McGlinchey M. J. , Osella D.
Published: December 2018

Cyclohexane-1R,2R-diamine carrier ligand increases the selectivity towards colon cancer cells with respect to diamines in asymmetrical (acetato)(carboxylato)platinum(iv) prodrugs.
Hazard assessment of quinaldine-, alkylcarbazole-, benzene- and toluene-based liquid organic hydrogen carrier (LOHCs) systems
Authors: Markiewicz Marta , Zhang Ya-Qi , Empl Michael T. , Lykaki Marianna , Thöming Jorg , Steinberg Pablo , Stolte Stefan
Published: December 2018

Proactive, comparative environmental hazard assessment of LOHC systems based on alkylcarbazoles, quinaldine, benzene and toluene including H2-rich, H2-lean and partially hydrogenated forms.
Flowback verses first-flush: new information on the geochemistry of produced water from mandatory reporting
Authors: Stringfellow William T. , Camarillo Mary Kay
Published: December 2018

Unconventional oil and gas development uses the subsurface injection of large amounts of a variety of industrial chemicals, and there are concerns about the return of these chemical to the surface with water produced with oil and gas from stimulated wells.
Enhanced intrinsic CYP3A4 activity in human hepatic C3A cells with optically controlled CRISPR/dCas9 activator complex
Authors: Han Shuo , Wei Shiruo , Wang Xuan , Han Xu , Zhang Mingzhi , Su Ming , Li Yang , Guo Jinhai , Zeng Wotan , Liu Jinwen , Gao Yi , Shen Li
Published: December 2018

Human hepatic C3A cells have been applied in bioartificial liver development, although these cells display low intrinsic cytochrome P450 3A4 (CYP3A4) enzyme activity.
Cellulose nanocrystals in nanoarchitectonics – towards photonic functional materials
Authors: Giese Michael , Spengler Matthias
Published: December 2018

This review summarizes the recent achievements in the development of photonic functional materials based on cellulose nanocrystals (CNCs) and CNC templating. The unique self-assembly of CNCs into chiral nematic structures introduces photonic properties for the development of functional materials with application potential in photonic sensing, tunable reflectors or optoelectronics.
Multifunctional Pt(iv) complexes containing a glutathione S-transferase inhibitor lead to enhancing anticancer activity and preventing metastasis of osteosarcoma cells
Authors: Chen Hong , Chen Feihong , Wang Xinyi , Gou Shaohua
Published: December 2018

Several Pt(iv) prodrugs conjugated with a glutathione S-transferase (GST) inhibitor were studied with the purpose of preventing the metastasis of osteosarcoma.
Cyclic iRGD peptide as a dual-functional on–off gatekeeper of mesoporous nanocontainers for targeting NRP-1 and selective drug release triggered by conformational conversion
Authors: Lee Jeonghun , Oh Eun-Taex , Lee Jinyoung , Kang Taehyeong , Kim Ha Gyeong , Kang Hansol , Park Heon Joo , Kim Chulhee
Published: December 2018

A cyclic iRGD peptide as a dual-functional on–off gatekeeper on the surface of MSNs is prepared for specific NRP-1 targeting and selective drug release by conformational conversion.
Electrochemical behavior of inorganic–organic hybrid polyoxometalate ((Cys)3[PW12O40]) nanostructure self-assembled monolayer on polycrystalline gold electrode surfaces
Authors: Dianat Somayeh , Hatefi-Mehrjardi Abdolhamid , Mahmoodzadeh Kourosh
Published: December 2018

The synergistic effect of HPW and Cys enhanced electrochemical activity of Au-(Cys)PW electrode.
KTlO: a metal shrouded 2D semiconductor with high carrier mobility and tunable magnetism
Authors: Song Ya-Qian , Yuan Jun-Hui , Li Li-Heng , Xu Ming , Wang Jia-Fu , Xue Kan-Hao , Miao Xiang-Shui
Published: December 2018

Two-dimensional materials with high carrier mobility and tunable magnetism are in high demand for nanoelectronic and spintronic applications.
Tunable synthesis of quinolinone-fused isoquinolines through sequential one-pot nucleophilic addition and palladium-catalyzed intramolecular C–H alkenylation
Authors: Li Xue , Bian Yunyun , Chen Xin , Zhang Hang , Wang Wei , Ren Sida , Yang Xuechen , Lu Chang , Chen Chunxia , Peng Jinsong
Published: December 2018

An efficient sequential one-pot synthesis of N-fused heterocycles based on 4-quinolinone and isoquinoline scaffolds of biological interest has been developed.
Crotonols A and B, two rare tigliane diterpenoid derivatives against K562 cells from Croton tiglium
Authors: Wang Junfeng , Qin Li , Zhao Biqing , Cai Liang , Zhong Zhenping , Liu Yonghong , Zhou Xiaojiang
Published: December 2018

Crotonol B (2) represents the first example of 13,14-seco-tigliane diterpenoids.
Synthesis of modified β-methoxyphenylalanines via diazonium chemistry and their incorporation in desoxycyclomarin analogues
Authors: Kiefer Alexander , Kazmaier Uli
Published: December 2018

Chloramphenicol base is converted into substituted syn-β-methoxyphenylalanins, building blocks of modified cyclomarins.
Reactive cyclic intermediates in the ProTide prodrugs activation: trapping the elusive pentavalent phosphorane
Authors: Procházková Eliška , Navrátil Rafael , Janeba Zlatko , Roithová Jana , Baszczyňski Ondřej
Published: December 2018

A combination of NMR and IRPD spectroscopy confirmed the existence of predicted cyclic phosphorus intermediates involved in ProTide prodrugs activation.
Discovery of fluorescent 3-heteroarylcoumarin derivatives as novel inhibitors of anaplastic lymphoma kinase
Authors: Mah Shinmee , Jang Jaebong , Song Daesun , Shin Yongje , Latif Muhammad , Jung Yongwon , Hong Sungwoo
Published: December 2018

Coumarin-based ALK inhibitors were identified as a new template for the development of novel fluorescent ALK inhibitors, which can be tracked using microscopy techniques.
Radical SAM-dependent adenosylation catalyzed by l-tyrosine lyases
Authors: Wu Yujie , Wu Runze , Mandalapu Dhanaraju , Ji Xinjian , Chen Tuo , Ding Wei , Zhang Qi
Published: December 2018

Tyrosine analogues containing an olefin moiety can be adenosylated by l-tyrosine lyases.
A NIR light-triggered pyroelectric-dominated generator based on a liquid crystal elastomer composite actuator for photoelectric conversion and self-powered sensing
Authors: Wei Wanyuan , Gao Jingjing , Yang Jingfeng , Wei Jie , Guo Jinbao
Published: December 2018

A NIR light-driven pyroelectric-dominated generator based on a photomechanical liquid crystal elastomer composite actuator have been developed for the first time.
High-performance yttrium-iron alloy doped Pt-free catalysts on graphene for hydrogen evolution
Authors: Zhu Pengcheng , Lyu Dandan , Shen Pei Kang
Published: December 2018

Research into the preparation and application of metal/graphene nanocomposite materials is an important issue in the field of graphene applications.
Constructing stable ordered ion channels for a solid electrolyte membrane with high ionic conductivity by combining the advantages of liquid crystal and ionic liquid
Authors: Wang Shi , Zeng Qinghui , Wang Ailian , Liu Xu , Chen Jie , Wang Zhinan , Zhang Liaoyun
Published: December 2018

Ordered ion channels were constructed using liquid crystal, while ionic liquid was inserted into the channels for fast transport ions.
Ultrahigh energy density of a N, O codoped carbon nanosphere based all-solid-state symmetric supercapacitor
Authors: Song Ziyang , Zhu Dazhang , Li Liangchun , Chen Tao , Duan Hui , Wang Zhiwei , Lv Yaokang , Xiong Wei , Liu Mingxian , Gan Lihua
Published: December 2018

A novel quinone–amine route is developed to fabricate N, O codoped carbon nanospheres for an all-solid-state supercapacitor with an ultrahigh energy density.
GPR120 protects lipotoxicity-induced pancreatic β-cell dysfunction through regulation of PDX1 expression and inhibition of islet inflammation
Authors: Wang Yi , Xie Ting , Zhang Dan , Leung Po Sing
Published: December 2018

G-protein coupled receptor 120 (GPR120) has been shown to act as an omega-3 unsaturated fatty acid sensor and is involved in insulin secretion. However, the underlying mechanism in pancreatic β cells remains unclear. To explore the potential link between GPR120 and β-cell function, its agonists docosahexaenoic acid (DHA) and GSK137647A were used in palmitic acid (PA)-induced pancreatic β-cell dysfunction, coupled with GPR120 knockdown (KD) in MIN6 cells and GPR120 knockout (KO) mice to identify the underlying signaling pathways. In vitro and ex vivo treatments of MIN6 cells and islets isolated from wild-type (WT) mice with DHA and GSK137647A restored pancreatic duodenal homeobox-1 (PDX1) expression levels and β-cell function via inhibiting PA-induced elevation of proinflammatory chemokines and activation of nuclear factor κB, c-Jun amino (N)-terminal kinases1/2 and p38MAPK signaling pathways. On the contrary, these GPR120 agonism-mediated protective effects were abolished in GPR120 KD cells and islets isolated from GPR120 KO mice. Furthermore, GPR120 KO mice displayed glucose intolerance and insulin resistance relative to WT littermates, and β-cell functional related genes were decreased while inflammation was exacerbated in islets with increased macrophages in pancreas from GPR120 KO mice. DHA and GSK137647A supplementation ameliorated glucose tolerance and insulin sensitivity, as well as improved Pdx1 expression and islet inflammation in diet-induced obese WT mice, but not in GPR120 KO mice. These findings indicate that GPR120 activation is protective against lipotoxicity-induced pancreatic β-cell dysfunction, via the mediation of PDX1 expression and inhibition of islet inflammation, and that GPR120 activation may serve as a preventative and therapeutic target for obesity and diabetes.
Bregman inverse filter
Authors: Deng G. , Broadbridge P.
Published: December 2018

An inverse problem in which the observed signal is produced by passing the original signal through a filter that is derived from a convex minimisation problem is dealt. The filter is available as a black box. It is shown that the Bregman iteration, which is a tool for convex optimisation, can be used to solve this inverse problem. This novel application of the Bregman iteration is demonstrated through successful restoration of the original image from images filtered by a low‐pass filter. Theoretical analysis is conducted to explain the inversion process.
Compact microstrip balanced bandpass filter with adjustable transmission zeros
Authors: Xiao Jian‐Kang , Su Xiao‐Bao , Wang Hui‐Xia , Ma Jian‐Guo
Published: December 2018

A compact microstrip balanced bandpass filter (BPF) with a pair of adjustable transmission zeros (TZs) and a common mode suppression of over 20 dB in a frequency range of >2.42f0 by using the mixed electromagnetic coupling technology has been developed. The filter TZs in differential‐mode are attributed to the mixed electromagnetic coupling, and can be adjusted by the electric/magnetic coupling individually. The filter bandwidth can also be controlled by the electromagnetic coupling. The proposed balanced BPF has been fabricated and measured, and the prediction has been demonstrated.
Homogenisation model for calculating multi‐point grounding current of transformer core
Authors: Zhou Lijun , Jiang Junfei , Liu Huancheng , Gao Shibin , Li Wei , Zhang Chenqingyu
Published: December 2018

Multi‐point grounding of the core is one of the common transformer faults. In this study, a homogenisation model based on the finite element method is developed for calculating multi‐point grounding current of the transformer core. The equivalent conductivity in the direction normal to the laminations is determined by the analysis of fault current distribution and calculation of anisotropic resistances of the iron core, especially, considering the influence of insulation coating on the silicon steel sheet. The validity of the proposed model is verified by comparing the three‐dimensional finite element simulation results with the experimental results. Finally, two typical faults are simulated to further study the characteristics of multi‐point grounding current based on a distribution transformer, which may be useful for the optimisation of transformer core design.
Backstepping direct thrust force control for sensorless PMLSM drive
Authors: Ting Chen‐Sheng , Chang Yong‐Nong , Chen Yen‐Yo
Published: December 2018

This study presents an analytic designing approach for the sensorless direct thrust force control (DTFC) of permanent magnet linear synchronous motor (PMLSM). A modified stator flux estimator developed by use of an adaptive mechanism and correction factors is devoted to measuring the stator flux linkage and the mover's position. The parameters of the flux estimator are adjusted in advance through an off‐line identification process to increase the accuracy of estimation. Based on the principle of backstepping control, the reference q‐axis flux command, which is equivalent to the thrust force command, is first obtained from the Lyapunov functional analysis. Then, the reference d‐axis flux command is calculated according to the characteristics of stator flux linkage. The voltage control strategy is constructed to stabilise the global system and ensure the convergence of DTFC. Compared to the conventional direct torque/thrust control, the proposed control scheme can apply the space vector modulation to achieve a fixed switching frequency. Consequently, the phenomenon of flux and force ripples inherited from DTFC is improved. The experiment results are provided to validate the proposed control approach. Moreover, a recent work that is based on the optimal control is adopted as a comparison study.
Modelling and performance analysis on a bearingless fixed‐pole rotor induction motor
Authors: Ye Xiaoting , Yang Zebin , Zhang Tao
Published: December 2018

Both torque winding magnetic field and suspension force winding magnetic field induce currents in the rotor in conventional bearingless induction motors (BIMs). Owing to the induced currents of suspension force winding, the air gap magnetic field is affected, which results in amplitude and phase error of torque and radial suspension forces. To overcome such drawbacks, a novel BIM with a fixed‐pole rotor is proposed, which is called bearingless fixed‐pole rotor induction (BFPRI) motor. First, the structure of the BFPRI motor is designed and introduced. Second, the mathematical models of radial suspension forces and torque are deduced. Third, the corresponding electromagnetic characteristics, including induced currents, radial suspension forces, and torque, are investigated and compared with the conventional BIM. Finally, the prototype motor equipped with a fixed‐pole rotor is constructed and experimental research is carried out. According to the finite element analysis and experimental results, for the proposed BFPRI motor, only the torque winding magnetic field induces currents in the rotor, which makes the precision of torque and radial suspension forces higher and improves the accuracy of the BIM control system.
RES and battery fed energy efficient single‐phase induction motor drive system with retrofit solution
Authors: Dhara Sumon , Jain Sachin , Agarwal Vivek
Published: December 2018

The usage of renewable energy sources (RESs) with energy storage like battery and so on in the stand‐alone household and commercial purpose is becoming popular. These systems have to manage the requirement with the generated energy from the RES. Further, in a typical stand‐alone household application, a significant amount of power is consumed by single‐phase induction motor (SPIM) fans in the form of the ceiling, pedestal formats. So, it is necessary to save energy by operating them efficiently and economically in a stand‐alone system. This study proposes a fractional flux‐based V/f control strategy for speed control of a SPIM. The proposed retrofit scheme is simple and is easy to implement. It minimises the magnetisation loss irrespective of the fan speed and also saves nearly 10–20% of power consumption as compared to the conventional voltage control method. Further, in this study, a new performance parameter is defined which helps in determining an economic zone in variable speed operation SPIM. In this economic zone of operation, a particular battery can deliver power for an extended time. All the details with respect to analysis, modelling, simulation and experimental results to support the proposed strategy are presented in this study.
Dual‐stator consequent‐pole Vernier PM motor with improved power factor
Authors: Gorginpour Hamed
Published: December 2018

The Vernier permanent‐magnet (VPM) machines are recently attracting more attention for utilisation in low‐speed, high‐torque applications including renewable energy conversion systems, electric vehicles and elevators. Although, the VPM machines present interesting advantages, they suffer from lower power factor (PF) in comparison to the conventional permanent‐magnet (PM) drives. In this study, a novel structure of the VPM machine with dual‐stator and consequent‐pole (CP) rotor topology is proposed with enhanced PF. The objectives in this new structure are achieving higher torque density per PM volume, higher efficiency, simpler and more robust installation of PM pieces, lower cogging torque and simpler rotor core laminations compared to the previously proposed VPM structures with reasonably improved PF. The low PF issue of VPM machines is analysed in details and the novel CP‐VPM geometry is designed to diminish this drawback. Then analytical relations are derived based on the magnetic‐equivalent‐circuit for evaluating the flux density distribution, induced back electromotive force, magnetising reactance and PF. The effectiveness of the novel structure in enhancing the operating features is validated using analytical and 2D‐FE simulation results. Finally, it is concluded that the performance of the optimally designed structure can be enhanced reasonably so that to consider it as a good choice for direct‐drive applications.
Comparison of rotor electrical fault indices owing to inter‐turn short circuit and unbalanced resistance in doubly‐fed induction generator
Authors: Moosavi Seyed‐Mohammad M. , Faiz Jawad , Abadi Mohsen B. , Cruz Sergio M.A.
Published: December 2018

Doubly‐fed induction generator (DFIG) is the dominant technology in the wind energy market. Rotor inter‐turn short‐circuits (RITSCs) and unbalanced rotor resistance (URR) are the main types of rotor electrical asymmetries in DFIG. The URR has already been considered as an electrical fault or asymmetry in the rotor of DFIG. Although the RITSC introduces URR into the rotor circuit its consequences are not similar due to the structure of the machine and presence of current controllers in the DFIG system. In this study, both RITSC and URR are proposed and compared, and the detection of these faults was performed using appropriate indices in the stator current, reactive power, and rotor modulating voltage signals, which are available in the control system of the DFIG. Furthermore, it is supposed that the discrimination between these two types of faults is feasible by utilising proper fault indices at various operating regions of the wind turbine. The performance of the defined fault indices, for different fault severities, is verified using an experimental setup with the DFIG operating under several conditions such as different power injection into the grid and different rotor speeds, including sub‐synchronous and super‐synchronous operation.
Experimental evaluation of dynamic performance of three‐phase AC–DC PWM rectifier with PD‐type‐2 fuzzy neural network controller
Authors: Acikgoz Hakan , Coteli Resul , Dandil Besir , Ata Fikret
Published: December 2018

Diode and thyristor‐based rectifier circuits have been widely used in the industry. Due to non‐linear structures of these circuits, they draw non‐sinusoidal current from AC network as well as cause a low power factor in the AC side. The DC‐link voltage of rectifier is affected by the changes in AC network or by the load variations on the DC side. Pulse‐width modulated (PWM) rectifiers can eliminate the mentioned power quality problems if they control properly. This study proposes a controller with an adaptive and robust structure based on proportional + derivative type‐2 fuzzy neural network (PD‐T2FNN) for DC‐link voltage control of PWM rectifier. Dynamic performance of PWM rectifier using the proposed controller is evaluated via dSPACE based experimental setup under different operation conditions: set‐point change, step load change in the DC side of the rectifier, set‐point change under load and capacitive operation mode. The experimental results are given for traditional PD and proportional + integral and T2FNN controllers to validity performance of the proposed controller. Performances of controllers are evaluated regarding settling time, overshoot, steady‐state error and total harmonic distortion. PWM rectifier with PD‐T2FNN DC‐link voltage controller has superior performance for all operating conditions according to performance criteria when compared with other controllers.
Algorithm‐based direct power control of active front‐end rectifiers
Authors: Kumar Amit , Srungavarapu Gopalakrishna
Published: December 2018

Switching Table‐based Direct Power Control (ST‐DPC) is one of the most widely used techniques in Active Front‐End (AFE) rectifiers. Proper control of switching states of the power converter is essential to obtain better power quality performance and quicker response to the load demand. In the classical ST‐DPC techniques such as Virtual Flux with Noguchi's Table‐based DPC (VF‐NT‐DPC) and Virtual Flux with Improved Table‐based DPC (VF‐IT‐DPC) etc., these switching states are decided based on a predefined static switching table. Hence, they have poor power quality and dynamic performance with load variations. In this research work, in‐depth mathematical analysis is carried out based on the quantised values of ‘the rate of change of active and reactive powers’ and an algorithm is introduced for AFEs. Since, the proposed algorithm is considering the quantised values of ‘the rate of change of active and reactive powers’, which is dynamic in nature; therefore, it has reduced THD, lesser power ripple, and quicker response than classical ST‐DPC techniques. To show the superiority of the Algorithm based DPC (A‐DPC) technique experimental work is carried out and the power quality performance of the proposed A‐DPC is compared with conventional ST‐DPC techniques VF‐NT‐DPC and VF‐IT‐DPC.
Adapted near‐state PWM for dual two‐level inverters in order to reduce common‐mode voltage and switching losses
Authors: Aghazadeh Amir , Khodabakhshi‐Javinani Naser , Nafisi Hamed , Davari Masoud , Pouresmaeil Edris
Published: December 2018

In this paper, a near‐state pulse‐width modulation (NSPWM) algorithm is proposed and implemented on dual‐two‐level voltage‐source inverters (D2L‐VSIs) in order to reduce the common‐mode voltage (CMV), the inverter switching losses, the current total harmonic distortion, and the side effects of bearing currents ‐‐compared with space vector modulation (SVM) and PWM7. To gain these goals, two conventional two‐level inverters of the D2L‐VSI are controlled, separately, with specific switching sequences and an adjusted phase difference between the carriers of two inverters. For evaluating and comparing these PWM techniques mathematically, both CMV root mean square generated and switching losses of the D2L‐VSI are formulated as a function of the power factor of the D2L‐VSI, which is driven by the methods detailed in this study. Eventually, theories and analysis, as well as simulations and experimental results ‐‐which are generated by MATLAB/Simulink environment and a 300 W scaled‐down D2LVSI prototype, respectively ‐‐authenticate the superiority of the proposed NSPWM over both SVM and PWM7.
Risk‐constrained scheduling of solar‐based three state compressed air energy storage with waste thermal recovery unit in the thermal energy market environment
Authors: Jadidbonab Mohammad , Mousavi‐Sarabi Hesameddin , Mohammadi‐Ivatloo Behnam
Published: December 2018

This paper evaluates the self‐scheduling problem for solar‐based compressed air energy storage (CAES) plant with capability of compression waste thermal energy recovery via information gap decision theory (IGDT) approach. This feature gives the plant the ability to make income through participation in the thermal energy market. Moreover, the proposed plant uses natural gas as input fuel, which makes the system flexible to operate as a simple cycle gas generator when the stored air is drained. The utilisation of renewable energies in spite of many benefits has some challenges to self‐scheduling of the solar‐based three state CAES plant such as volatility and unpredictability. In addition, the uncertain solar farm generation is modelled by IGDT method. By the proposed IGDT model, the plant can pursue risk‐taker and risk‐averse strategies to face with different situations related to uncertain parameter. Finally, the numerical results obtained from case studies validate the appropriateness of the proposed approach.
Gravity and inertial load adaptive control of wall‐climbing robot
Authors: Dong Shuang
Published: December 2018

The five‐degree‐of‐freedom double‐legged wall‐climbing robot is the most straightforward structure with the promising application because the minimum degree‐of‐freedom of the foot‐type climbing robot with continuous movement and obstacle‐overcoming capability on the vertical wall is five. Based on the prototype of the wall‐climbing robot, the parameter table of the Denavit‐Hartenberg (DH) model is given out, and then the positive and inverse solutions of kinematics analysis of wall‐climbing robot are derived. Secondly, the system dynamics model is established based on the Lagrange equation, and the weights of inertial load acceleration torque, Coriolis force torque, centrifugal force torque and gravity torque in the dynamic equation are analysed. The design ideas of compensation gravity load and inertial load adaptive proportional differential controller is proposed according to the analysis results, and the gravity torque compensation function and general nonlinear mass function are given correspondingly to provide theoretical support to adaptive controller design. Finally, the effectiveness of the control strategy was verified by the actual control of the knee joint and ankle joint.
Non-thermal pressure support in X-COP galaxy clusters
Authors: Eckert D. , Ghirardini V. , Ettori S. , Rasia E. , Biffi V. , Pointecouteau E. , Rossetti M. , Molendi S. , Vazza F. , Gastaldello F. , Gaspari M. , De Grandi S. , Ghizzardi S. , Bourdin H. , Tchernin C. , Roncarelli M.
Published: December 2018

Galaxy clusters are the endpoints of structure formation and are continuously growing through the merging and accretion of smaller structures. Numerical simulations predict that a fraction of their energy content is not yet thermalized, mainly in the form of kinetic motions (turbulence, bulk motions). Measuring the level of non-thermal pressure support is necessary to understand the processes leading to the virialization of the gas within the potential well of the main halo and to calibrate the biases in hydrostatic mass estimates. We present high-quality measurements of hydrostatic masses and intracluster gas fraction out to the virial radius for a sample of 13 nearby clusters with availableXMM-NewtonandPlanckdata. We compare our hydrostatic gas fractions with the expected universal gas fraction to constrain the level of non-thermal pressure support. We find that hydrostatic masses require little correction and infer a median non-thermal pressure fraction of ∼6% and ∼10% atR500andR200, respectively. Our values are lower than the expectations of hydrodynamical simulations, possibly implying a faster thermalization of the gas. If instead we use the mass calibration adopted by thePlanckteam, we find that the gas fraction of massive local systems implies a mass bias 1 − b = 0.85 ± 0.05 for Sunyaev–Zeldovich-derived masses, with some evidence for a mass-dependent bias. Conversely, the high bias required to matchPlanckcosmic microwave background and cluster count cosmology is excluded by the data at high significance, unless the most massive halos are missing a substantial fraction of their baryons.