bluuebunny/crossref_metadata_2025 huggingface dataset:
A compound-based proteomic approach discloses 15-ketoatractyligenin methyl ester as a new PPARγ partial agonist with anti-proliferative ability
Authors: Vasaturo Michele , Fiengo Lorenzo , De Tommasi Nunziatina , Sabatino Lina , Ziccardi Pamela , Colantuoni Vittorio , Bruno Maurizio , Cerchia Carmen , Novellino Ettore , Lupo Angelo , Lavecchia Antonio , Piaz Fabrizio Dal
Published: January 2017

Proteomics based approaches are emerging as useful tools to identify the targets of bioactive compounds and elucidate their molecular mechanisms of action. Here, we applied a chemical proteomic strategy to identify the peroxisome proliferator-activated receptor γ (PPARγ) as a molecular target of the pro-apoptotic agent 15-ketoatractyligenin methyl ester (compound 1). We demonstrated that compound 1 interacts with PPARγ, forms a covalent bond with the thiol group of C285 and occupies the sub-pocket between helix H3 and the β-sheet of the ligand-binding domain (LBD) of the receptor by Surface Plasmon Resonance (SPR), mass spectrometry-based studies and docking experiments. 1 displayed partial agonism of PPARγ in cell-based transactivation assays and was found to inhibit the AKT pathway, as well as its downstream targets. Consistently, a selective PPARγ antagonist (GW9662) greatly reduced the anti-proliferative and pro-apoptotic effects of 1, providing the molecular basis of its action. Collectively, we identified 1 as a novel PPARγ partial agonist and elucidated its mode of action, paving the way for therapeutic strategies aimed at tailoring novel PPARγ ligands with reduced undesired harmful side effects.
Advanced Materials From Fungal Mycelium: Fabrication and Tuning of Physical Properties
Authors: Haneef Muhammad , Ceseracciu Luca , Canale Claudio , Bayer Ilker S. , Heredia-Guerrero José A. , Athanassiou Athanassia
Published: January 2017

In this work is presented a new category of self-growing, fibrous, natural composite materials with controlled physical properties that can be produced in large quantities and over wide areas, based on mycelium, the main body of fungi. Mycelia from two types of edible, medicinal fungi, Ganoderma lucidum and Pleurotus ostreatus, have been carefully cultivated, being fed by two bio-substrates: cellulose and cellulose/potato-dextrose, the second being easier to digest by mycelium due to presence of simple sugars in its composition. After specific growing times the mycelia have been processed in order to cease their growth. Depending on their feeding substrate, the final fibrous structures showed different relative concentrations in polysaccharides, lipids, proteins and chitin. Such differences are reflected as alterations in morphology and mechanical properties. The materials grown on cellulose contained more chitin and showed higher Young’s modulus and lower elongation than those grown on dextrose-containing substrates, indicating that the mycelium materials get stiffer when their feeding substrate is harder to digest. All the developed fibrous materials were hydrophobic with water contact angles higher than 120°. The possibility of tailoring mycelium materials’ properties by properly choosing their nutrient substrates paves the way for their use in various scale applications.
Iterative Neighbour-Information Gathering for Ranking Nodes in Complex Networks
Authors: Xu Shuang , Wang Pei , Lü Jinhu
Published: January 2017

Designing node influence ranking algorithms can provide insights into network dynamics, functions and structures. Increasingly evidences reveal that node’s spreading ability largely depends on its neighbours. We introduce an iterative neighbourinformation gathering (Ing) process with three parameters, including a transformation matrix, a priori information and an iteration time. The Ing process iteratively combines priori information from neighbours via the transformation matrix, and iteratively assigns an Ing score to each node to evaluate its influence. The algorithm appropriates for any types of networks, and includes some traditional centralities as special cases, such as degree, semi-local, LeaderRank. The Ing process converges in strongly connected networks with speed relying on the first two largest eigenvalues of the transformation matrix. Interestingly, the eigenvector centrality corresponds to a limit case of the algorithm. By comparing with eight renowned centralities, simulations of susceptible-infected-removed (SIR) model on real-world networks reveal that the Ing can offer more exact rankings, even without a priori information. We also observe that an optimal iteration time is always in existence to realize best characterizing of node influence. The proposed algorithms bridge the gaps among some existing measures, and may have potential applications in infectious disease control, designing of optimal information spreading strategies.
PrimerSuite: A High-Throughput Web-Based Primer Design Program for Multiplex Bisulfite PCR
Authors: Lu Jennifer , Johnston Andrew , Berichon Philippe , Ru Ke-lin , Korbie Darren , Trau Matt
Published: January 2017

The analysis of DNA methylation at CpG dinucleotides has become a major research focus due to its regulatory role in numerous biological processes, but the requisite need for assays which amplify bisulfite-converted DNA represents a major bottleneck due to the unique design constraints imposed on bisulfite-PCR primers. Moreover, a review of the literature indicated no available software solutions which accommodated both high-throughput primer design, support for multiplex amplification assays, and primer-dimer prediction. In response, the tri-modular software package PrimerSuite was developed to support bisulfite multiplex PCR applications. This software was constructed to (i) design bisulfite primers against multiple regions simultaneously ( PrimerSuite ), (ii) screen for primer-primer dimerizing artefacts ( PrimerDimer ), and (iii) support multiplex PCR assays ( PrimerPlex ). Moreover, a major focus in the development of this software package was the emphasis on extensive empirical validation, and over 1300 unique primer pairs have been successfully designed and screened, with over 94% of them producing amplicons of the expected size, and an average mapping efficiency of 93% when screened using bisulfite multiplex resequencing. The potential use of the software in other bisulfite-based applications such as methylation-specific PCR is under consideration for future updates. This resource is freely available for use at PrimerSuite website (www.primer-suite.com).
Functional PTGS2 polymorphism-based models as novel predictive markers in metastatic renal cell carcinoma patients receiving first-line sunitinib
Authors: Cebrián Arancha , Gómez del Pulgar Teresa , Méndez-Vidal María José , Gonzálvez María Luisa , Lainez Nuria , Castellano Daniel , García-Carbonero Iciar , Esteban Emilio , Sáez Maria Isabel , Villatoro Rosa , Suárez Cristina , Carrato Alfredo , Munárriz-Ferrándiz Javier , Basterrechea Laura , García-Alonso Mirta , González-Larriba José Luis , Perez-Valderrama Begoña , Cruz-Jurado Josefina , González del Alba Aránzazu , Moreno Fernando , Reynés Gaspar , Rodríguez-Remírez María , Boni Valentina , Mahillo-Fernández Ignacio , Martin Yolanda , Viqueira Andrea , García-Foncillas Jesús
Published: January 2017

Sunitinib is the currently standard treatment for metastatic renal cell carcinoma (mRCC). Multiple candidate predictive biomarkers for sunitinib response have been evaluated but none of them has been implemented in the clinic yet. The aim of this study was to analyze single nucleotide polymorphisms (SNPs) in genes linked to mode of action of sunitinib and immune response as biomarkers for mRCC. This is a multicenter, prospective and observational study involving 20 hospitals. Seventy-five mRCC patients treated with sunitinib as first line were used to assess the impact of 63 SNPs in 31 candidate genes on clinical outcome. rs2243250 (IL4) and rs5275 (PTGS2) were found to be significantly associated with shorter cancer-specific survival (CSS). Moreover, allele C (rs5275) was associated with higher PTGS2 expression level confirming its functional role. Combination of rs5275 and rs7651265 or rs2243250 for progression free survival (PFS) or CSS, respectively, was a more valuable predictive biomarker remaining significant after correction for multiple testing. It is the first time that association of rs5275 with survival in mRCC patients is described. Two-SNP models containing this functional variant may serve as more predictive biomarkers for sunitinib and could suppose a clinically relevant tool to improve the mRCC patient management.
Effects of ultrasonic vibration on the microstructure and mechanical properties of high alloying TiAl
Authors: Ruirun Chen , Deshuang Zheng , Tengfei Ma , Hongsheng Ding , Yanqing Su , Jingjie Guo , Hengzhi Fu
Published: January 2017

To modify the microstructure and enhance performances, the ultrasonic vibration is applied in the mould casting of TiAl alloy. The effects and mechanism of ultrasonic vibration on the solidifying microstructure and mechanical properties are investigated and the model for predicting lamellar colony size is established. After ultrasonic vibration, the coarse microstructure is well modified and lamellar colony is refined from 534 μm to 56 μm. Most of precipitated phases are dissolved into the lamellar colony leading to a homogenous element distribution. The phase ratio of α2-Ti3Al and γ-TiAl is increased, and the chemical composition is promoted to more close to equilibrium level by weakening the influence of β-alloying elements. The microhardness and yield strength are gradually improved by 23.72% and 181.88% due to the fine grain strengthening, while the compressive strength is enhanced by 24.47% through solution strengthening. The critical ultrasonic intensity (Ib) for TiAl alloy is estimated at 220 W cm−2 and the model for average lamellar colony size is established as "Equation missing". The ultrasonic refinement efficiency exponentially increases as the ultrasonic vibration time with a theoretic limit maximum value of Elim = 88% and the dominating refinement mechanism by ultrasonic vibration is the cavitation-enhanced nucleation rather than cavitation-induced dendrite fragmentation.
White matter changes in microstructure associated with a maladaptive response to stress in rats
Authors: Magalhães R , Bourgin J , Boumezbeur F , Marques P , Bottlaender M , Poupon C , Djemaï B , Duchesnay E , Mériaux S , Sousa N , Jay T M , Cachia A
Published: January 2017

In today’s society, every individual is subjected to stressful stimuli with different intensities and duration. This exposure can be a key trigger in several mental illnesses greatly affecting one’s quality of life. Yet not all subjects respond equally to the same stimulus and some are able to better adapt to them delaying the onset of its negative consequences. The neural specificities of this adaptation can be essential to understand the true dynamics of stress as well as to design new approaches to reduce its consequences. In the current work, we employed ex vivo high field diffusion magnetic resonance imaging (MRI) to uncover the differences in white matter properties in the entire brain between Fisher 344 (F344) and Sprague–Dawley (SD) rats, known to present different responses to stress, and to examine the effects of a 2-week repeated inescapable stress paradigm. We applied a tract-based spatial statistics (TBSS) analysis approach to a total of 25 animals. After exposure to stress, SD rats were found to have lower values of corticosterone when compared with F344 rats. Overall, stress was found to lead to an overall increase in fractional anisotropy (FA), on top of a reduction in mean and radial diffusivity (MD and RD) in several white matter bundles of the brain. No effect of strain on the white matter diffusion properties was observed. The strain-by-stress interaction revealed an effect on SD rats in MD, RD and axial diffusivity (AD), with lower diffusion metric levels on stressed animals. These effects were localized on the left side of the brain on the external capsule, corpus callosum, deep cerebral white matter, anterior commissure, endopiriform nucleus, dorsal hippocampus and amygdala fibers. The results possibly reveal an adaptation of the SD strain to the stressful stimuli through synaptic and structural plasticity processes, possibly reflecting learning processes.
Histamine H3R receptor activation in the dorsal striatum triggers stereotypies in a mouse model of tic disorders
Authors: Rapanelli M , Frick L , Pogorelov V , Ohtsu H , Bito H , Pittenger C
Published: January 2017

Tic disorders affect ~5% of the population and are frequently comorbid with obsessive-compulsive disorder, autism, and attention deficit disorder. Histamine dysregulation has been identified as a rare genetic cause of tic disorders; mice with a knockout of the histidine decarboxylase (Hdc) gene represent a promising pathophysiologically grounded model. How alterations in the histamine system lead to tics and other neuropsychiatric pathology, however, remains unclear. We found elevated expression of the histamine H3 receptor in the striatum of Hdc knockout mice. The H3 receptor has significant basal activity even in the absence of ligand and thus may modulate striatal function in this knockout model. We probed H3R function using specific agonists. The H3 agonists R-aminomethylhistamine (RAMH) and immepip produced behavioral stereotypies in KO mice, but not in controls. H3 agonist treatment elevated intra-striatal dopamine in KO mice, but not in controls. This was associated with elevations in phosphorylation of rpS6, a sensitive marker of neural activity, in the dorsal striatum. We used a novel chemogenetic strategy to demonstrate that this dorsal striatal activity is necessary and sufficient for the development of stereotypy: when RAMH-activated cells in the dorsal striatum were chemogenetically activated (in the absence of RAMH), stereotypy was recapitulated in KO animals, and when they were silenced the ability of RAMH to produce stereotypy was blocked. These results identify the H3 receptor in the dorsal striatum as a contributor to repetitive behavioral pathology.
Large grain growth for hole-conductor-free fully printable perovskite solar cells via polyoxometalate molecular doping
Authors: Zhang Yuzhuo , Wang Yanju , Sun Zhixia , Li Fengyan , Tao Ran , Jin Zhanbin , Xu Lin
Published: January 2017

Polyoxometalate-induced Ostwald ripening process occurring during the crystal grain growth of perovskite film, achieving a grain size of 30 μm.
A highly sensitive and selective fluorescence off–on probe for the detection of intracellular endogenous tyrosinase activity
Authors: Wu Xiaofeng , Li Xiaohua , Li Hongyu , Shi Wen , Ma Huimin
Published: January 2017

A fluorescent probe with a low background signal and high sensitivity is developed and applied to image the relative levels of tyrosinase activity in different cells.
Surface-selective direct 17O DNP NMR of CeO2 nanoparticles
Authors: Hope Michael A. , Halat David M. , Magusin Pieter C. M. M. , Paul Subhradip , Peng Luming , Grey Clare P.
Published: January 2017

We demonstrate surface-selective direct 17O DNP, showing the first three layers of CeO2 nanoparticles can be distinguished with high selectivity.
Ag containing porous Au structures as highly selective catalysts for glycolate and formate
Authors: Thia Larissa , Xie Mingshi , Kim Donghwan , Wang Xin
Published: January 2017

Selectivity results obtained when glycerol electro-oxidation was carried out over various porous Au catalysts.
The degradation mechanism of sulfamethoxazole under ozonation: a DFT study
Authors: Yu Hang , Ge Pu , Chen Jingwen , Xie Hongbin , Luo Yi
Published: January 2017

Sulfamethoxazole (SMX), a kind of antibiotic, remains in the environment and threatens public health.
Shedding light on the biological and chemical fingerprints of three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia)
Authors: Zengin Gokhan , Aktumsek Abdurrahman , Ceylan Ramazan , Uysal Sengul , Mocan Andrei , Guler Gokalp Ozmen , Mahomoodally M. Fawzi , Glamočlija Jasmina , Ćirić Ana , Soković Marina
Published: January 2017

Representatives of theAchilleagenus are widely used as foods or nutraceuticals.
Electrochemical determination of trace pesticide residues based on multiwalled carbon nanotube grafted acryloyloxy ferrocene carboxylates with different spacers
Authors: Xu Feng , Cui Zhuo-Miao , Li He , Luo Yan-Ling
Published: January 2017

We report the preparation of nanohybrid composites with good electrochemical response for the detection of pesticide residues by combining esterification with ATRP.
Synthesis and characterization of boron-doped ordered mesoporous carbon by evaporation induced self-assembly under HCl conditions
Authors: Zhang Yan , Dai Wenwen , Liu Yujian , Ma Binge
Published: January 2017

With double-layer hydrogen bonding and electrostatic Coulomb forces acting as the driving force, the obtained B-OMC has the well-ordered mesoporous structure, highest surface area (689.85 m2 g−1) and boron content (1.96 wt%) when pH = 4.
Cd2SnO4 transparent conductive oxide: a promising alternative candidate for highly efficient hybrid halide perovskite solar cells
Authors: Liu Dong , Ren Shengqiang , Ma Xiao , Liu Cai , Wu Lili , Li Wei , Zhang Jingquan , Feng Lianghuan
Published: January 2017

We introduce a Cd2SnO4 film for constructing a perovskite device with a novel structure. The Cd2SnO4 film has higher optical transmission in the visible region than an FTO substrate, and an average PCE of 15.58% under AM 1.5 irradiation.
Fischer–Tropsch synthesis: effect of ammonia on product selectivities for a Pt promoted Co/alumina catalyst
Authors: Rao Pendyala Venkat Ramana , Shafer Wilson D. , Jacobs Gary , Martinelli Michela , Sparks Dennis E. , Davis Burtron H.
Published: January 2017

The effects of co-fed ammonia in synthesis gas on the activity and product selectivities of a typical cobalt catalyst (0.5% Pt–25% Co/Al2O3) were investigated during the Fischer–Tropsch synthesis using a continuously stirred tank reactor (CSTR).
Physical principles of graphene cellular interactions: computational and theoretical accounts
Authors: Chen Pengyu , Yan Li-Tang
Published: January 2017

Clarifying the physical principles of graphene cellular interactions is critical for the wider application of graphene-based nanomaterials in nanomedicine. This review highlights the advances in computational and theoretical accounts for this emerging field.
Narrowband spectrally selective near-infrared photodetector based on up-conversion nanoparticles used in a 2D hybrid device
Authors: Zhou Nan , Xu Bing , Gan Lin , Zhang Junpei , Han Junbo , Zhai Tianyou
Published: January 2017

A hybrid (NaYF4:Yb/Er@NaYF4:Nd/Yb)/MoS2 device structure is proposed to realize narrow spectral window photodetection in the near-infrared region.
Band gap evolution and a piezoelectric-to-electrostrictive crossover in (1 − x)KNbO3–x(Ba0.5Bi0.5)(Nb0.5Zn0.5)O3 ceramics
Authors: Pascual-Gonzalez Cristina , Schileo Giorgio , Khesro Amir , Sterianou Iasmi , Wang Dawei , Reaney Ian M. , Feteira Antonio
Published: January 2017

A piezoelectric-to-electrostrictive crossover in (1 − x)KNbO3–x(Ba0.5Bi0.5)(Nb0.5Zn0.5)O3.
Creation and imitation of a milk flavour
Authors: Zhu Guangyong , Xiao Zuobing
Published: January 2017

Flavour plays a crucial role in food and is the most important aspect of milk.
Rock-salt-type nanoprecipitates lead to high thermoelectric performance in undoped polycrystalline SnSe
Authors: Tang Guodong , Wen Qiang , Yang Teng , Cao Yang , Wei Wei , Wang Zhihe , Zhang Zhidong , Li Yusheng
Published: January 2017

We report a highZTvalue of 1.3 at 850 K for undoped polycrystalline SnSe, and ascribe it to the newly identified cubic Rock-salt nanoprecipitates.
Bonds broken and formed during the mixed-linkage glucan : xyloglucan endotransglucosylase reaction catalysed by Equisetum hetero-trans-β-glucanase
Authors: Simmons Thomas J. , Fry Stephen C.
Published: January 2017

Mixed-linkage glucan∶xyloglucan endotransglucosylase (MXE) is one of the three activities of the recently characterised hetero-trans-β-glucanase (HTG), which among land plants is known only from Equisetum species. The biochemical details of the MXE reaction were incompletely understood — details that would promote understanding of MXE's role in vivo and enable its full technological exploitation. We investigated HTG's site of attack on one of its donor substrates, mixed-linkage (1→3),(1→4)-β-d-glucan (MLG), with radioactive oligosaccharides of xyloglucan as the acceptor substrate. Comparing three different MLG preparations, we showed that the enzyme favours those with a high content of cellotetraose blocks. The reaction products were analysed by enzymic digestion, thin-layer chromatography (TLC), high-pressure liquid chromatography (HPLC) and gel-permeation chromatography (GPC). Equisetum HTG consistently cleaved the MLG at the third consecutive β-(1→4)-bond following (towards the reducing terminus) a β-(1→3)-bond. It then formed a β-(1→4)-bond between the MLG and the non-reducing terminal glucose residue of the xyloglucan oligosaccharide, consistent with its xyloglucan endotransglucosylase/hydrolase subfamily membership. Using size-homogeneous barley MLG as the donor substrate, we showed that HTG does not favour any particular region of the MLG chain relative to the polysaccharide's reducing and non-reducing termini; rather, it selects its target cellotetraosyl unit stochastically along the MLG molecule. This work improves our understanding of how enzymes can exhibit promiscuous substrate specificities and provides the foundations to explore strategies for engineering novel substrate specificities into transglycanases.
Contribution of innate immune cells to pathogenesis of severe influenza virus infection
Authors: Cole Suzanne L. , Ho Ling-Pei
Published: January 2017

Influenza A viruses (IAVs) cause respiratory illness of varying severity based on the virus strains, host predisposition and pre-existing immunity. Ultimately, outcome and recovery from infection rely on an effective immune response comprising both innate and adaptive components. The innate immune response provides the first line of defence and is crucial to the outcome of infection. Airway epithelial cells are the first cell type to encounter the virus in the lungs, providing antiviral and chemotactic molecules that shape the ensuing immune response by rapidly recruiting innate effector cells such as NK cells, monocytes and neutrophils. Each cell type has unique mechanisms to combat virus-infected cells and limit viral replication, however their actions may also lead to pathology. This review focuses how innate cells contribute to protection and pathology, and provides evidence for their involvement in immune pathology in IAV infections.
A novel support vector machine robust model based electrical equaliser for coherent optical orthogonal frequency division multiplexing systems
Authors: Mhatli Sofien , Mrabet Hichem , Dayoub Iyad , Giacoumidis Elias
Published: January 2017

Classifiers, such as artificial neural networks non‐linear equaliser (ANN‐NLE), Wiener–Hammerstein non‐linear equaliser, Volterra non‐linear equaliser (Volterra‐NLE) and support vector machine non‐linear equaliser (SVM‐NLE), can play a significant role in compensating non‐linear imperfections in the optical communications context. Using classifiers to mitigate the non‐linear effects in coherent optical orthogonal frequency division multiplexing (CO‐OFDM) systems is an interesting idea to be investigated. In this study, a novel support vector machine robust version, specifically adapted to a 100 Gb/s CO‐OFDM data structure for long haul distance, is proposed. Firstly, the authors demonstrate that SVM‐NLE upgrades the system performance by about 10−1 in terms of bit‐error rate compared to Volterra‐NLE at optical signal‐to‐noise ratio equal to 14 dB. Then, they show that it can double the transmission distance up to 1600 km over single mode fibre channel. Furthermore, a performance comparison is performed using 16 quadrature amplitude modulation and 40 Gb/s bit rate for SVM‐NLE, ANN‐NLE and inverse Volterra series transfer function non‐linear equaliser, respectively.
D‐patches: effective traffic sign detection with occlusion handling
Authors: Rehman Yawar , Riaz Irfan , Fan Xue , Shin Hyunchul
Published: January 2017

In advanced driver assistance systems, accurate detection of traffic signs plays an important role in extracting information about the road ahead. However, traffic signs are persistently occluded by vehicles, trees, and other structures on road. Performance of a detector decreases drastically when occlusions are encountered especially when it is trained using full object templates. Therefore, we propose a new method called discriminative patches (d‐patches), which is a traffic sign detection (TSD) framework with occlusion handling capability. D‐patches are those regions of an object that possess the most discriminative features than their surroundings. They are mined during training and are used for classification instead of the full object templates. Furthermore, we observe that the distribution of redundant‐detections around a true‐positive is different from that around a false‐positive. Based on this observation, we propose a novel hypothesis generation scheme that uses a voting and penalisation mechanism to accurately select a true‐positive candidate. We also introduce a new Korean TSD (KTSD) dataset with several evaluation settings to facilitate detector's evaluation under different conditions. The proposed method achieves 100% detection accuracy on German TSD benchmark and achieves 4.0% better detection accuracy, when compared with other well‐known methods (under partially occluded settings), on KTSD dataset.
Adaptive distance protection for grounded fault of lines connected with doubly‐fed induction generators
Authors: Chen Shi , Tai Nengling , Fan Chunju , Liu Jian , Hong Shubin
Published: January 2017

Crowbar circuit is a preferred solution to maintaining wind generators connected to the grid during a disturbance. However, the activation of crowbar protection will lead to an obvious difference between the positive sequence impedance of wind generators and the negative sequence one. This study analyses the influence of this unique fault characteristic of doubly‐fed induction generators (DFIGs) on the three zones of distance relays. When the transmission line emanates from a DFIG‐based wind farm, there exists a high probability that the conventional protective zones of distance relays fail to operate. Hence, an adaptive branch coefficient is proposed to calculate the zone 2 setting according to the fault type and equivalent sequence impedances of wind generators. The proposed adaptive setting principle realises a better coverage of zone 2 and enhances the reliability and sensitivity of the relays. Simulation results verify the improvement of the protective zone of distance relays.
Fuzzy based methodologies comparison for high‐impedance fault diagnosis in radial distribution feeders
Authors: Tonelli‐Neto Mauro S. , Decanini José Guilherme M.S. , Lotufo Anna Diva P. , Minussi Carlos Roberto
Published: January 2017

This study presents a comparison of two developed intelligent systems that carries out, in an integrated manner, failure diagnosis on electric power distribution feeders. These procedures aim to identify and classify critical situations, as high‐impedance faults, which can potentially damage the system components and cause power supply interruptions to consumers. The intelligent systems combine the wavelet transform, Dempster–Shafer evidence theory, voting scheme, fuzzy inference system and artificial neural networks. Results show the efficiency, reliability, and robustness of the proposed methodology, allowing its real‐time application.
Characterisation of long‐term voltage stability with variable‐speed wind power generation
Authors: Amarasekara Kanchana , Meegahapola Lasantha G. , Agalgaonkar Ashish P. , Perera Sarath
Published: January 2017

Voltage stability in general is of paramount importance with increasing penetration levels of variable‐speed wind power generators (VSWGs) in power systems. Limited knowledge exists considering the impact of VSWGs on long‐term voltage stability (LTVS) of power systems, focusing on doubly fed induction generators and full‐converter wind generators. This paper presents the results of a comprehensive study on the impact of VSWGs on LTVS. Integration of wind generators while operating the existing synchronous generators improves the LTVS. However, it is unlikely that power systems will retain all existing synchronous generators operating, with high wind penetration levels. Therefore, this study compares the capability of the synchronous generators and VSWGs on LTVS by considering the dynamic reactive power capabilities. The significance of overload capability of synchronous generators on LTVS is highlighted. It is also illustrated that integrating wind farms at remote and local locations from load centres has distinct impacts on LTVS. Replacement of synchronous generators located in close proximity to load centres has a detrimental effect on LTVS. Furthermore, this study demonstrates the impact of different wind generator loading levels on LTVS. The study outcomes highlight several distinct factors which influence the LTVS of power systems with high wind penetration levels.
Nonlinear resonances and multi-stability in simple neural circuits
Authors: Alonso Leandro M.
Published: January 2017

This article describes a numerical procedure designed to tune the parameters of periodically driven dynamical systems to a state in which they exhibit rich dynamical behavior. This is achieved by maximizing the diversity of subharmonic solutions available to the system within a range of the parameters that define the driving. The procedure is applied to a problem of interest in computational neuroscience: a circuit composed of two interacting populations of neurons under external periodic forcing. Depending on the parameters that define the circuit, such as the weights of the connections between the populations, the response of the circuit to the driving can be strikingly rich and diverse. The procedure is employed to find circuits that, when driven by external input, exhibit multiple stable patterns of periodic activity organized in complex tuning diagrams and signatures of low dimensional chaos.
Effect of precursor and composition on the physical properties of the low-cost solution processed Cu2ZnSnS4 thin film for solar photovoltaic application
Authors: Gupta Goutam Kumar , Dixit Ambesh
Published: January 2017

Quaternary compound semiconductor Cu2ZnSnS4 (CZTS) has been prepared using two different precursors sols, chlorides and nitrates, using spin coating process to get phase pure and less defective thin films for solar photovoltaics. The synthesized CZTS thin films are heat treated at different temperatures to achieve the kesterite crystallographic phase. The prepared thin films are highly textured along (112) axis. The surface microscopic images suggest that chloride precursor derived CZTS thin films are relatively uniform and densely packed as compared to nitrate precursors. The dislocation density is ∼1 × 1016 lines m−2 for the chloride precursor derived thin films, much lower than that of the nitride precursor derived CZTS thin films. The optical absorption measurements suggest the direct optical gap ∼1.52 eV for CZTS thin films derived from both the precursor routes. However, electrical resistivity measurements suggest that resistivity is uniform and much lower ∼0.025 Ω cm for chloride precursor CZTS thin films, alike nitride precursor CZTS thin films, where resistivity is three orders of magnitude higher ∼30 Ω cm. These studies suggest that chloride precursor derived CZTS thin films are of high quality and can be used for solar photovoltaic applications.
Analysis of thermionic bare tether operation regimes in passive mode
Authors: Sanmartín J. R. , Chen Xin , Sánchez-Arriaga G.
Published: January 2017

A thermionic bare tether (TBT) is a long conductor coated with a low work-function material. In drag mode, a tether segment extending from anodic end A to a zero-bias point B, with the standard Orbital-motion-limited current collection, is followed by a complex cathodic segment. In general, as bias becomes more negative in moving from B to cathodic end C, one first finds space-charge-limited (SCL) emission covering up to some intermediate point B*, then full Richardson-Dushman (RD) emission reaching from B* to end C. An approximate analytical study, which combines the current and voltage profile equations with results from asymptotic studies of the Vlasov-Poisson system for emissive probes, is carried out to determine the parameter domain covering two limit regimes, which are effectively controlled by just two dimensionless parameters involving ambient plasma and TBT material properties. In one such limit regime, no point B* is reached and thus no full RD emission develops. In an opposite regime, SCL segment BB* is too short to contribute significantly to the current balance.
Modeling and optimization of a solar parabolic trough concentrator system using inverse artificial neural network
Authors: May Tzuc O. , Bassam A. , Escalante Soberanis M. A. , Venegas-Reyes E. , Jaramillo O. A. , Ricalde Luis J. , Ordoñez Eduardo E. , El Hamzaoui Y.
Published: January 2017

In this paper, an artificial neural network inverse (ANNi) model is applied to optimize the thermal performance (η) of parabolic trough concentrators. A feedforward neural network architecture is trained using an experimental database from parabolic trough concentrators operations. Rim angle (φr), inlet (Tin) and outlet (Tout) fluid temperatures, ambient temperature (Ta), water flow (Fw), direct solar radiation (Gb), and the wind velocity (Vw) were used as main input variables within the neural network model to estimate the thermal performance with a correlation coefficient of R2 = 0.9996 between experimental and simulated values. The sensitivity analysis is carried out to verify the effect of all input variables. The optimal operation conditions of parabolic trough concentrators are established using artificial neural network inverse modeling (ANNi) to achieve optimal operation conditions of parabolic trough concentrators. The results indicated that ANNi is a feasible tool for Parabolic Trough Concentrators optimization.
Optical generation of pure spin currents at the indirect gap of bulk Si
Authors: Bottegoni F. , Zucchetti C. , Ciccacci F. , Finazzi M. , Isella G.
Published: January 2017

We report on the optical generation of a pure spin current at the indirect gap of bulk Si at room temperature in the photon energy range comprised between 1.2 and 1.8 eV. Spin-polarized electrons are promoted to the Δ-valleys of the Si Brillouin zone by circularly polarized light. The photo-generated spin current is then detected by exploiting a Schottky Pt/Si(001) junction: spin-polarized electrons diffuse toward the Pt/Si interface and enter the Pt layer where the spin current is converted into a transverse electromotive field through the inverse spin-Hall effect (ISHE). The photon energy dependence of the ISHE signal is interpreted in the frame of a one-dimensional spin drift-diffusion model, which allows estimating the electron spin lifetime to be τs=15±5 ns.
An intelligent multi-agent based improved approach for conventional and renewable power generation operation and control
Authors: Garduno-Ramirez Raul , Borunda Mónica
Published: January 2017

In recent years, efforts have been increasing to develop hybrid power generation systems, which consist of a mixture of renewable, conventional, and storage systems. The variability and non-dispatchability of some renewable sources as well as the attainment of tight performance requirements make the development of control systems for power plants in hybrid systems a remarkably challenging task. A promising approach to solve this problem is to apply the paradigm of Multi-Agent Systems, from Artificial Intelligence, which is currently carried out in two phases: engineering design and engineering implementation. This paper presents the engineering design, including the definition, description, and allocation of the Intelligent Agents of an improved Intelligent Multi-Agent System for Supervision and Control (iMASSC), which is proposed to create intelligent power plants from either renewable or conventional power generation units. In addition, simulations of a wind turbine generator model equipped with iMASSC are provided to demonstrate the feasibility of this methodology. The iMASSC approach uses a Multi-Agent System with a generic structure and takes into account the complexity of current power plants, which is more realistic than the single Intelligent Agent approach commonly found in the literature. This provides a scalable, modular, customizable, and functional framework to create intelligent power plants regardless of being conventional or not. Eventually, the community of intelligent power plants will achieve the objectives of the hybrid power system through autonomous and coherent collaboration. Hence, the proposed iMASSC model is expected to provide feasible solutions to the operation of modern hybrid power generation systems.
X-ray standing wave enhanced scattering from mesoporous silica thin films
Authors: Wu Longlong , Liu Yupu , Wang Xiao , Wang Geng , Zhao Dongyuan , Chen Gang
Published: January 2017

X-ray standing wave enhanced scattering effects are observed in mesoporous silica thin films (MSTFs) deposited on rough indium tin oxide coated glass substrates in grazing-incidence small-angle x-ray scattering studies. The distorted-wave Born approximation theory along with a rigorous wave function analysis is employed to elucidate the dynamical scattering processes occurring in MSTFs. The data analysis is significantly simplified by expressing the x-ray scattering intensity from MSTFs in two separate functions of the wave vector transfer, where the in-plane correlation between neighboring mesopore channels is decoupled from the out-of-plane interference interaction. Remarkable agreement is achieved between experiment and theory.
Higher-order diffraction suppression of free-standing quasiperiodic nanohole arrays in the x-ray region
Authors: Li Hailiang , Shi Lina , Wei Lai , Xie Changqing , Cao Leifeng
Published: January 2017

Nanohole array is particularly advantageous for light field manipulation. Here, we report a strategy to mimic the function of x-ray transmission gratings with free-standing quasiperiodic nanohole array. An analytical description is developed to reveal the physical mechanism of the free-standing quasiperiodic nanohole array that reduces higher-order contamination, and is verified by rigorous numerical simulations. An x-ray free-standing quasiperiodic nanohole array consisting of 1.6 × 109 nanoholes over an active area of 10 mm × 10 mm was fabricated. Experimental results of near-complete suppression of higher-order diffractions were obtained in the x-ray region. The capability to separate multiple overlapping orders makes this kind of nanohole array attractive for future development and application of high-resolution spectroscopy.
Demagnetization investigation of a partitioned rotor flux switching machine with hybrid permanent magnet
Authors: Fan Deyang , Quan Li , Zhu Xiaoyong , Xiang Zixuan , Wu Wenye
Published: January 2017

In this paper, the partitioned rotor flux switching permanent magnet machine with ferrite permanent magnet is proposed. By the adoption of the partitioned rotor configuration, the stator flux leakage is eliminated and the permanent magnet utilization is improved. The ferrite permanent magnet machine often suffers from irreversible demagnetization due to the inherent relatively low coercivity of ferrite permanent magnet. To mitigate the machine irreversible demagnetization risk, an improved partitioned rotor flux switching permanent magnet machine with hybrid permanent magnet topology is also proposed. Two little pieces of rare-earth permanent magnet are installed at the corners of ferrite permanent magnet, thus forming the hybrid permanent magnet topology. And the demagnetization mechanisms of both machines are clarified by the magnetic equivalent circuit method, which prove that the rare-earth permanent magnet offer magnetic protection function for the ferrite permanent magnet. Furthermore, by the 2-D finite element analysis, the demagnetization characteristics and the electromagnetic performances of the two machines are quantitively assessed, revealing that the demagnetization risk is reduced significantly. Both theoretical analysis and simulation results verify that the improved machine can not only maintain low-cost design, but also possess enhanced demagnetization withstand capability and competitive electromagnetic performances as expected.
Power distribution of a co-axial dual-mechanical-port flux-switching permanent magnet machine for fuel-based extended range electric vehicles
Authors: Zhou Lingkang , Hua Wei , Zhang Gan
Published: January 2017

In this paper, power distribution between the inner and outer machines of a co-axial dual-mechanical-port flux-switching permanent magnet (CADMP-FSPM) machine is investigated for fuel-based extended range electric vehicle (ER-EV). Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced, which consist of an inner FSPM machine used for high-speed, an outer FSPM machine for low-speed, and a magnetic isolation ring between them. Then, the magnetic field coupling of the inner and outer FSPM machines is analyzed with more attention paid to the optimization of the isolation ring thickness. Thirdly, the power-dimension (PD) equations of the inner and outer FSPM machines are derived, respectively, and thereafter, the PD equation of the whole CADMP-FSPM machine can be given. Finally, the PD equations are validated by finite element analysis, which supplies the guidance on the design of this type of machines.
Anisotropic crystallization in solution processed chalcogenide thin film by linearly polarized laser
Authors: Gu Tingyi , Jeong Hyuncheol , Yang Kengran , Wu Fan , Yao Nan , Priestley Rodney D. , White Claire E. , Arnold Craig B.
Published: January 2017

The low activation energy associated with amorphous chalcogenide structures offers broad tunability of material properties with laser-based or thermal processing. In this paper, we study near-bandgap laser induced anisotropic crystallization in solution processed arsenic sulfide. The modified electronic bandtail states associated with laser irradiation lead to a distinctive photoluminescence spectrum, compared to thermally annealed amorphous glass. Laser crystalized materials exhibit a periodic subwavelength ripple structure in transmission electron microscopy experiments and show polarization dependent photoluminescence. Analysis of the local atomic structure of these materials using laboratory-based X-ray pair distribution function analysis indicates that laser irradiation causes a slight rearrangement at the atomic length scale, with a small percentage of S-S homopolar bonds converting to As-S heteropolar bonds. These results highlight fundamental differences between laser and thermal processing in this important class of materials.
Induction of dormancy in hypoxic human papillomavirus-positive cancer cells
Authors: Hoppe-Seyler Karin , Bossler Felicitas , Lohrey Claudia , Bulkescher Julia , Rösl Frank , Jansen Lars , Mayer Arnulf , Vaupel Peter , Dürst Matthias , Hoppe-Seyler Felix
Published: January 2017

Significance

Human papillomaviruses (HPVs) are major human carcinogens. It is widely assumed that HPV-positive tumor cells must sustain viral
E6/E7
oncogene expression to continuously block the tumor-suppressive senescence response of the host cell. Consequently, E6/E7 are considered attractive therapeutic targets for immunotherapy or for functional inhibition. Here we show that hypoxic conditions, as often found in HPV-positive cancers, allow the cells to induce a dormant state in which E6/E7 is down-regulated but induction of senescence is avoided. Instead, a reversible growth arrest is induced that can be overcome by reoxygenation. As a consequence, hypoxic HPV-positive cancer cells are protected against chemotherapy as well as against virus-specific therapeutic approaches, and may serve as reservoirs for cancer recurrence on reoxygenation.
Nickel pincer model of the active site of lactate racemase involves ligand participation in hydride transfer
Authors: Xu Tao , Wodrich Matthew D. , Scopelliti Rosario , Corminboeuf Clemence , Hu Xile
Published: January 2017

Significance

Pincer complexes are widely applied in homogeneous catalysis. However, only very recently has the first pincer complex been discovered in the active site of a metalloenzyme, namely, lactate racemase. Here, we report a synthetic model of the active site of lactate racemase. The nickel pincer model not only reproduces some key structural features of the active site, but also mediates the dehydrogenation of alcohols, a reaction relevant to lactate racemization. Our work suggests a mechanism in which the unique pyridinium-derived SCS pincer ligand actively participates in the hydride transfer. This work not only represents a successful biomimetic study of this enzyme but also lays the foundation for the development of new bioinspired pincer ligands.
Mutation of a kinase allosteric node uncouples dynamics linked to phosphotransfer
Authors: Ahuja Lalima G. , Kornev Alexandr P. , McClendon Christopher L. , Veglia Gianluigi , Taylor Susan S.
Published: January 2017

Significance

Our Girvan–Newman-based community network analysis provides a strategy to explore the effects of protein kinase mutations on the dynamic properties of the kinase core and the allosteric network underlying the catalytic cycle. With this approach, which allows us to identify subtle shifts in dynamics and in particular side-chain rotamer preferences, we can explain the underlying mechanism for loss of function in many different scenarios. Our method is especially relevant for disease-causing mutations that lie far from the active site but show no obvious structural perturbations based on X-ray crystallography.
Non-conventional arguments
Authors: Frenda Alessio S.
Published: January 2017

In the Romance context, Sicilian rather unusually allows finite verbs to be governed by a preposition within a subordinate phrasal constituent expressing purpose. In other Romance languages, the verb slotted in this context is normally an infinitive. Sicilian also has the corresponding infinitive construction, and the distribution of these two functionally equivalent structures in a corpus of Sicilian folk tales is analysed, revealing overall conciseness conditions restricting the occurrence of the finite-verb construction. The two structures are then analysed from a semantic and syntactic point of view, employing the formalism of Role and Reference Grammar, in order to understand what distinguishes them in terms of event structure and its expression via core complementation vs. adjunction.
The organizational structure of lexical compound verbs in Japanese
Authors: Toratani Kiyoko
Published: January 2017

This study offers a Construction Morphology account of the organizational structure of the class of lexical compound verbs in Japanese, covering two newly proposed types (thematic and aspectual compound verbs) (Kageyama 2013) and two understudied types (prefixed and lexicalized type compound verbs), as an alternative to a traditional listing of types. It argues that compounds are arranged in two dimensions: one contains the inheritance hierarchy, with its root node diverging according to the position of the semantic head (for thematic, aspectual, and prefixed type compounds); the other covers compounds with extended senses (for the lexicalized type). The study also proposes constructional schemas for compound verbs (e.g. those with affixoids such as -hateru ‘completely’) to illustrate how they are organized in the inheritance hierarchy.