bluuebunny/crossref_metadata_2025 huggingface dataset:
Celecoxib exerts protective effects in the vascular endothelium via COX-2-independent activation of AMPK-CREB-Nrf2 signalling
Authors: Al-Rashed Fahad , Calay Damien , Lang Marie , Thornton Clare C. , Bauer Andrea , Kiprianos Allan , Haskard Dorian O. , Seneviratne Anusha , Boyle Joseph J. , Schönthal Alex H. , Wheeler-Jones Caroline P. , Mason Justin C.
Published: April 2018

Although concern remains about the athero-thrombotic risk posed by cyclo-oxygenase (COX)-2-selective inhibitors, recent data implicates rofecoxib, while celecoxib appears equivalent to NSAIDs naproxen and ibuprofen. We investigated the hypothesis that celecoxib activates AMP kinase (AMPK) signalling to enhance vascular endothelial protection. In human arterial and venous endothelial cells (EC), and in contrast to ibuprofen and naproxen, celecoxib induced the protective protein heme oxygenase-1 (HO-1). Celecoxib derivative 2,5-dimethyl-celecoxib (DMC) which lacks COX-2 inhibition also upregulated HO-1, implicating a COX-2-independent mechanism. Celecoxib activated AMPKα(Thr172) and CREB-1(Ser133) phosphorylation leading to Nrf2 nuclear translocation. Importantly, these responses were not reproduced by ibuprofen or naproxen, while AMPKα silencing abrogated celecoxib-mediated CREB and Nrf2 activation. Moreover, celecoxib induced H-ferritin via the same pathway, and increased HO-1 and H-ferritin in the aortic endothelium of mice fed celecoxib (1000 ppm) or control chow. Functionally, celecoxib inhibited TNF-α-induced NF-κB p65(Ser536) phosphorylation by activating AMPK. This attenuated VCAM-1 upregulation via induction of HO-1, a response reproduced by DMC but not ibuprofen or naproxen. Similarly, celecoxib prevented IL-1β-mediated induction of IL-6. Celecoxib enhances vascular protection via AMPK-CREB-Nrf2 signalling, a mechanism which may mitigate cardiovascular risk in patients prescribed celecoxib. Understanding NSAID heterogeneity and COX-2-independent signalling will ultimately lead to safer anti-inflammatory drugs.
Assessing the quality of supplementary sensory feedback using the crossmodal congruency task
Authors: Blustein Daniel , Wilson Adam , Sensinger Jon
Published: April 2018

Advanced neural interfaces show promise in making prosthetic limbs more biomimetic and ultimately more intuitive and useful for patients. However, approaches to assess these emerging technologies are limited in scope and the insight they provide. When outfitting a prosthesis with a feedback system, such as a peripheral nerve interface, it would be helpful to quantify its physiological correspondence, i.e. how well the prosthesis feedback mimics the perceived feedback in an intact limb. Here we present an approach to quantify this aspect of feedback quality using the crossmodal congruency effect (CCE) task. We show that CCE scores are sensitive to feedback modality, an important characteristic for assessment purposes, but are confounded by the spatial separation between the expected and perceived location of a stimulus. Using data collected from 60 able-bodied participants trained to control a bypass prosthesis, we present a model that results in adjusted-CCE scores that are unaffected by percept misalignment which may result from imprecise neural stimulation. The adjusted-CCE score serves as a proxy for a feedback modality’s physiological correspondence or ‘naturalness’. This quantification approach gives researchers a tool to assess an aspect of emerging augmented feedback systems that is not measurable with current motor assessments.
Pressure induced superconductivity bordering a charge-density-wave state in NbTe4 with strong spin-orbit coupling
Authors: Yang Xiaojun , Zhou Yonghui , Wang Mengmeng , Bai Hua , Chen Xuliang , An Chao , Zhou Ying , Chen Qian , Li Yupeng , Wang Zhen , Chen Jian , Cao Chao , Li Yuke , Zhou Yi , Yang Zhaorong , Xu Zhu-An
Published: April 2018

Transition-metal chalcogenides host various phases of matter, such as charge-density wave (CDW), superconductors, and topological insulators or semimetals. Superconductivity and its competition with CDW in low-dimensional compounds have attracted much interest and stimulated considerable research. Here we report pressure induced superconductivity in a strong spin-orbit (SO) coupled quasi-one-dimensional (1D) transition-metal chalcogenide NbTe4, which is a CDW material under ambient pressure. With increasing pressure, the CDW transition temperature is gradually suppressed, and superconducting transition, which is fingerprinted by a steep resistivity drop, emerges at pressures above 12.4 GPa. Under pressurep = 69 GPa, zero resistance is detected with a transition temperatureTc = 2.2 K and an upper critical fieldμ0Hc2 = 2 T. We also find large magnetoresistance (MR) up to 102% at low temperatures, which is a distinct feature differentiating NbTe4from other conventional CDW materials.
Founder-specific inbreeding depression affects racing performance in Thoroughbred horses
Authors: Todd Evelyn T. , Ho Simon Y. W. , Thomson Peter C. , Ang Rachel A. , Velie Brandon D. , Hamilton Natasha A.
Published: April 2018

The Thoroughbred horse has played an important role in both sporting and economic aspects of society since the establishment of the breed in the 1700s. The extensive pedigree and phenotypic information available for the Thoroughbred horse population provides a unique opportunity to examine the effects of 300 years of selective breeding on genetic load. By analysing the relationship between inbreeding and racing performance of 135,572 individuals, we found that selective breeding has not efficiently alleviated the Australian Thoroughbred population of its genetic load. However, we found evidence for purging in the population that might have improved racing performance over time. Over 80% of inbreeding in the contemporary population is accounted for by a small number of ancestors from the foundation of the breed. Inbreeding to these ancestors has variable effects on fitness, demonstrating that an understanding of the distribution of genetic load is important in improving the phenotypic value of a population in the future. Our findings hold value not only for Thoroughbred and other domestic breeds, but also for small and endangered populations where such comprehensive information is not available.
The CPT1a inhibitor, etomoxir induces severe oxidative stress at commonly used concentrations
Authors: O’Connor Roddy S. , Guo Lili , Ghassemi Saba , Snyder Nathaniel W. , Worth Andrew J. , Weng Liwei , Kam Yoonseok , Philipson Benjamin , Trefely Sophie , Nunez-Cruz Selene , Blair Ian A. , June Carl H. , Milone Michael C.
Published: April 2018

Etomoxir (ETO) is a widely used small-molecule inhibitor of fatty acid oxidation (FAO) through its irreversible inhibitory effects on the carnitine palmitoyl-transferase 1a (CPT1a). We used this compound to evaluate the role of fatty acid oxidation in rapidly proliferating T cells following costimulation through the CD28 receptor. We show that ETO has a moderate effect on T cell proliferation with no observable effect on memory differentiation, but a marked effect on oxidative metabolism. We show that this oxidative metabolism is primarily dependent upon glutamine rather than FAO. Using an shRNA approach to reduce CPT1a in T cells, we further demonstrate that the inhibition of oxidative metabolism in T cells by ETO is independent of its effects on FAO at concentrations exceeding 5 μM. Concentrations of ETO above 5 μM induce acute production of ROS with associated evidence of severe oxidative stress in proliferating T cells. In aggregate, these data indicate that ETO lacks specificity for CTP1a above 5 μM, and caution should be used when employing this compound for studies in cells due to its non-specific effects on oxidative metabolism and cellular redox.
Comparative transcriptome analysis to investigate the potential role of miRNAs in milk protein/fat quality
Authors: Wang Xuehui , Zhang Li , Jin Jing , Xia Anting , Wang Chunmei , Cui Yingjun , Qu Bo , Li Qingzhang , Sheng Chunyan
Published: April 2018

miRNAs play an important role in the processes of cell differentiation, biological development, and physiology. Here we investigated the molecular mechanisms regulating milk secretion and quality in dairy cows via transcriptome analyses of mammary gland tissues from dairy cows during the high-protein/high-fat, low-protein/low-fat or dry periods. To characterize the important roles of miRNAs and mRNAs in milk quality and to elucidate their regulatory networks in relation to milk secretion and quality, an integrated analysis was performed. A total of 25 core miRNAs were found to be differentially expressed (DE) during lactation compared to non-lactation, and these miRNAs were involved in epithelial cell terminal differentiation and mammary gland development. In addition, comprehensive analysis of mRNA and miRNA expression between high-protein/high-fat group and low-protein/low-fat groups indicated that, 38 miRNAs and 944 mRNAs were differentially expressed between them. Furthermore, 38 DE miRNAs putatively negatively regulated 253 DE mRNAs. The putative genes (253 DE mRNAs) were enriched in lipid biosynthetic process and amino acid transmembrane transporter activity. Moreover, putative DE genes were significantly enriched in fatty acid (FA) metabolism, biosynthesis of amino acids, synthesis and degradation of ketone bodies and biosynthesis of unsaturated FAs. Our results suggest that DE miRNAs might play roles as regulators of milk quality and milk secretion during mammary gland differentiation.
The effect of aluminum and platinum additives on hydrogen adsorption on mesoporous silicates
Authors: Melaet Gérôme , Stavila Vitalie , Klebanoff Lennie , Somorjai Gabor A.
Published: April 2018

Recent theoretical predictions indicate that functional groups and additives could have a favorable impact on the hydrogen adsorption characteristics of sorbents; however, no definite evidence has been obtained to date and little is known about the impact of such modifications on the thermodynamics of hydrogen uptake and overall capacity.
Dependence of hot electron transfer on surface coverage and adsorbate species at semiconductor–molecule interfaces
Authors: Li Lesheng , Kanai Yosuke
Published: April 2018

Developing a molecular-level understanding of how a hot electron transfer process can be enhanced at semiconductor–molecule interfaces is central to advancing various future technologies.
Efficient visible light-driven water oxidation and proton reduction by an ordered covalent triazine-based framework
Authors: Xie Jijia , Shevlin Stephen A. , Ruan Qiushi , Moniz Savio J. A. , Liu Yangrong , Liu Xu , Li Yaomin , Lau Chi Ching , Guo Zheng Xiao , Tang Junwang
Published: April 2018

Efficient visible light driven water splitting on a covalent triazine-based framework with a controlled degree of conjugation.
Effect of diets with goat milk fat supplemented with exercise on anxiety and oxidative stress in the brains of adult rats
Authors: Barbosa Mayara Queiroga , Queiroga Rita de Cássia Ramos Egypto , Bertozzo Camila Carolina de Menezes Santos , Araújo Daline Fernandes de Souza , Oliveira Louise Iara Gomes , Silva Jaielison Yandro Pereira , Bomfim Marco Aurélio Delmondes , Guerra Gerlane Coelho Bernardo , Costa Suedna , Bessa Rui , Alves Susana , Barbosa Soares Juliana Kessia
Published: April 2018

Goat milk fat induced anxiolytic effect in sedentary animals; exercise promoted lipid peroxidation in the brain; exercise induced anxiety.
Detoxifying symbiosis: microbe-mediated detoxification of phytotoxins and pesticides in insects
Authors: Itoh Hideomi , Tago Kanako , Hayatsu Masahito , Kikuchi Yoshitomo
Published: April 2018

Symbiotic microorganisms degrade natural and artificial toxic compounds, and confer toxin resistance on insect hosts.
Aqueous medium-induced micropore formation in plasma polymerized polystyrene: an effective route to inhibit bacteria adhesion
Authors: Jijie Roxana , Barras Alexandre , Teslaru Teodora , Topala Ionut , Pohoata Valentin , Dobromir Marius , Dumych Tetiana , Bouckaert Julie , Szunerits Sabine , Dumitrascu Nicoleta , Boukherroub Rabah
Published: April 2018

Plasma polymerized styrene (pPS) films were successfully synthesized by means of an atmospheric pressure plasma technique, using a mixture of argon gas and styrene vapor.
Micro- and nano-structured 3D printed titanium implants with a hydroxyapatite coating for improved osseointegration
Authors: Qin Jie , Yang Dongqing , Maher Shaheer , Lima-Marques Luis , Zhou Yanmin , Chen Yujie , Atkins Gerald J. , Losic Dusan
Published: April 2018

3D printing technology combined with electrochemical nano-structuring and HA modification is a promising approach for the fabrication of Ti implants with improved osseointegration.
Engineering molecularly imprinted polymers (MIPs) for the selective extraction and quantification of the novel psychoactive substance (NPS) methoxphenidine and its regioisomers
Authors: Lowdon J. W. , Alkirkit S. M. O. , Mewis R. E. , Fulton D. , Banks C. E. , Sutcliffe O. B. , Peeters M.
Published: April 2018

The first developed Molecularly Imprinted Polymers (MIPs) for the specific detection of methoxphenidine (MXP) and its regioisomers.
Cysteine-reactive probes and their use in chemical proteomics
Authors: Hoch Dominic G. , Abegg Daniel , Adibekian Alexander
Published: April 2018

In this Feature article, we provide an insight into different chemoproteomic probes and techniques to study cysteines in complex proteomes.
High pressure NMR reveals conformational perturbations by disease-causing mutations in amyloid β-peptide
Authors: Rosenman David J. , Clemente Nicolina , Ali Muhammad , García Angel E. , Wang Chunyu
Published: April 2018

High pressure NMR reveals conformational biases in disease-causing variants of the Aβ monomer.
Controlled preparation of high quality WS2 nanostructures by a microwave-assisted solvothermal method
Authors: Yan Haiting , Li Jianhui , Liu Daomeng , Jing Xunan , Wang Daquan , Meng Lingjie
Published: April 2018

WS2 nanomaterials including nanosheets, nanocones and nanoworms were successfully synthesized by a facile and efficient microwave-assisted solvothermal method.
Unveiling the atomistic mechanisms for oxygen intercalation in a strongly interacting graphene–metal interface
Authors: Romero-Muñiz Carlos , Martín-Recio Ana , Pou Pablo , Gómez-Rodríguez José M. , Pérez Rubén
Published: April 2018

The atomistic mechanisms involved in the oxygen intercalation in the strongly interacting G/Rh(111) system are characterized in a comprehensive experimental and theoretical study, combining scanning tunneling microscopy and DFT calculations.
A novel nonlinear nano-scale wear law for metallic brake pads
Authors: Patil Sandeep P. , Chilakamarri Sri Harsha , Markert Bernd
Published: April 2018

In the present work, molecular dynamics simulations were carried out to investigate the temperature distribution as well as the fundamental friction characteristics such as the coefficient of friction and wear in a disc-pad braking system.
Mobilities of iodide anions in aqueous solutions for applications in natural dye-sensitized solar cells
Authors: Cassone Giuseppe , Calogero Giuseppe , Sponer Jiri , Saija Franz
Published: April 2018

Dye-sensitized solar cells (DSSCs) composed of aqueous electrolytes represent an environmentally friendly, low-cost, and concrete alternative to standard DSSCs and typical solar cells. A joint experimental/computational study revealed the microscopic details behind the conduction properties of iodide anions in aqueous dye-sensitized solar cells.
Eliminating common biases in modelling the electrical conductivity of carbon nanotube–polymer nanocomposites
Authors: Hoang Linh Trong , Leung Siu Ning , Zhu Zheng Hong
Published: April 2018

This work provides insights into a simulation approach to polymer nanocomposites’ electrical conductivity that can eliminate biases caused by common assumptions.
Photo-induced linkage isomerization in the gas phase probed by tandem ion mobility and laser spectroscopy
Authors: Choi Chang Min , MacAleese Luke , Dugourd Philippe , Choi Myoung Choul , Chirot Fabien
Published: April 2018

Ruthenium complexes involving sulfoxide ligands can undergo linkage isomerization upon light absorption, accompanied by dramatic changes in their optical properties.
Computational studies of micellar and nanoparticle nanomedicines
Authors: Sen Soumyo , Han Yanxiao , Rehak Pavel , Vuković Lela , Král Petr
Published: April 2018

The review highlights recent computational modeling of micellar and nanoparticle nanomedicines, which elucidates their functional roles in atomistic details.
Inversely polarised ferroelectric polymer contact electrodes for triboelectric-like generators from identical materials
Authors: Šutka A. , Mālnieks K. , Linarts A. , Timusk M. , Jurķāns V. , Gorņevs I. , Blūms J. , Bērziņa A. , Joost U. , Knite M.
Published: April 2018

Triboelectric nanogenerators based on ferroelectric materials exhibit boosted performance due to magnified induction by piezoelectric charges.
Functionalised microscale nanoband edge electrode (MNEE) arrays: the systematic quantitative study of hydrogels grown on nanoelectrode biosensor arrays for enhanced sensing in biological media
Authors: Piper Andrew , Alston Ben M. , Adams Dave J. , Mount Andrew R.
Published: April 2018

We demonstrate a hydrogel-coated nanoelectrode array biosensor that is resistant to biofouling.
The combined measurement of 87Sr/86Sr isotope ratios and 88Sr/85Rb elemental ratios using laser ablation MC-ICP-MS and its application for food provenance studies: the case for Asturian beans
Authors: Reguera-Galan Aida , Moldovan Mariella , Garcia Alonso J. Ignacio
Published: April 2018

By combining the 87Sr/86Sr isotope ratio with the 88Sr/85Rb elemental ratio the discrimination between Asturian and South American beans was possible.
Redox/ultrasound dual stimuli-responsive nanogel for precisely controllable drug release
Authors: Shen Nengwei , Lei Bin , Wang Yizhou , Xu Shouhong , Liu Honglai
Published: April 2018

Schematic representation of the preparation and the strategy of redox/ultrasound triggered drug release of the nanogel system.
Revisiting 1-chloro-1,2-benziodoxol-3-one: efficient ortho-chlorination of aryls under aqueous conditions
Authors: Vinayak Botla , Ravindrakumar Pardhi Vishal , Ramana Daggupati V. , Chandrasekharam Malapaka
Published: April 2018

The ortho-selective amide directing group assisted chlorination of aryls with the easily accessible 1-chloro-1,2-benziodoxol-3-one as oxidant as well as chlorinating reagent is reported in the absence of a radical initiator. The open air, aqueous conditions and recyclable reagent demonstrate the green principles involved in the reaction.
One step synthesis of a fused four-ring heterocycle
Authors: Solomos Marina A. , Bertke Jeffery A. , Swift Jennifer A.
Published: April 2018

The rearrangement of a diphenylurea to a more stable quinazolinone is confirmed through X-ray diffraction and DFT calculations.
Phase behaviors and characterization of magnetic microemulsions containing pentaalkylguanidinium-based magnetic room-temperature ionic liquids (MRTILs)
Authors: Dai Xuezhi , Qiang Xiaolian , Gao Jing , Teng Juan , Zang Huimin , Song Hang
Published: April 2018

Strong magnetic susceptibility and low viscosity magnetic microemulsions containing pentaalkylguanidinium-based magnetic room temperature ionic liquids.
Enhanced Li ion conductivity in Ge-doped Li0.33La0.56TiO3 perovskite solid electrolytes for all-solid-state Li-ion batteries
Authors: Hu Zhixiong , Sheng Jiali , Chen Jiahui , Sheng Guoqing , Li Yunming , Fu Xian-Zhu , Wang Lei , Sun Rong , Wong Ching-Ping
Published: April 2018

Ge-Doped Li0.33La0.56TiO3 perovskites are synthesized by solid-state reactions and have been demonstrated as Li-ion battery solid electrolytes with excellent ion conductivity and electrochemical stability.
Synthesis of dissymmetric phosphorus dendrimers using an unusual protecting group
Authors: Apartsin Evgeny K. , Venyaminova Alya G. , Mignani Serge , Caminade Anne-Marie , Majoral Jean-Pierre
Published: April 2018

We report the synthesis of neutral and polycationic dissymmetric phosphorus dendrimers bearing branches of different generations on the core.
Observation of dynamical crater-shaped charge distribution in the space–time imaging of monolayer graphene
Authors: Cho Jongweon , Tang Jau , Hwang Taek Yong , Zewail Ahmed H.
Published: April 2018

Space–time visualization of striking fluence-dependent carrier excitation, relaxation and diffusion dynamics in graphene, revealing a distinct transition from a Gaussian-shaped image at lower fluences to a crater-shaped pattern at higher fluences, is presented.
Multicomponent metal–organic framework derivatives for optimizing the selective catalytic performance of styrene epoxidation reaction
Authors: Hui Junfeng , Chu Huimin , Zhang Wenlei , Shen Yu , Chen Wanzheng , Hu Yu , Liu Wan , Gao Cong , Guo Shaohua , Xiao Gengwu , Li Sheng , Fu Yu , Fan Daidi , Zhang Weina , Huo Fengwei
Published: April 2018

Multicomponent MOF derivatives obtained by treating MOFs under suitable conditions exhibited high conversion and selectivity in the styrene epoxidation reaction.
Hierarchical TiN nanoparticles-assembled nanopillars for flexible supercapacitors with high volumetric capacitance
Authors: Qin Ping , Li Xingxing , Gao Biao , Fu Jijiang , Xia Lu , Zhang Xuming , Huo Kaifu , Shen Wenli , Chu Paul K.
Published: April 2018

Hierarchical TiN nanoparticles-assembled nanopillars arrays with excellent electrochemical performance were synthesized for flexible supercapacitors.
Co-exfoliation and fabrication of graphene based microfibrillated cellulose composites – mechanical and thermal stability and functional conductive properties
Authors: Phiri Josphat , Johansson Leena-Sisko , Gane Patrick , Maloney Thad C.
Published: April 2018

The excellent functional properties of graphene and micro-nanofibrillated cellulose (MNFC) offer plenty of possibilities for wide ranging applications in combination as a composite material.
How are 1,2,3-triazoles accommodated in helical secondary structures?
Authors: Ben Haj Salah Khoubaib , Das Sanjit , Ruiz Nicolas , Andreu Vanessa , Martinez Jean , Wenger Emmanuel , Amblard Muriel , Didierjean Claude , Legrand Baptiste , Inguimbert Nicolas
Published: April 2018

Peptaibols were used as templates to monitor the impact of 1,2,3-triazole (Tz) insertion in place of amide bonds in a helix structure.
Horner–Wadsworth–Emmons dispersion polymerization for the production of monodisperse conjugated polymer particles under ambient conditions
Authors: Ciftci Sibel , Jansen Felicitas , Chimisso Vittoria , Kler Joe , Rahimi Khosrow , Kuehne Alexander J. C.
Published: April 2018

Here we present the first metal-free dispersion polymerization yielding highly monodisperse conjugated polymer particles.
Installing lactone chain termini during photoinduced polymerization
Authors: Lauer Andrea , Steinkoenig Jan , Jöckle Philipp , Kelterer Anne-Marie , Unterreiner Andreas N. , Barner-Kowollik Christopher
Published: April 2018

We exploit the Thorpe–Ingold effect as a spontaneous end group transformation method during photo-induced polymerization of methacrylates using the functional (2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropio-phenone) species as radical photoinitiator.
In situ growth of PEDOT/graphene oxide nanostructures with enhanced electrochromic performance
Authors: Shi Yingdi , Zhang Yong , Tang Kai , Song Yanbin , Cui Jiewu , Shu Xia , Wang Yan , Liu Jiaqin , Wu Yucheng
Published: April 2018

Designed growth of a novel PEDOT/graphene oxide (GO) hybrid and obtained hybrid demonstrates superior electrochromic performance.
Palladium-catalyzed intramolecular C–H arylation of 2-halo-N-Boc-N-arylbenzamides for the synthesis of N–H phenanthridinones
Authors: Hu Quan-Fang , Gao Tian-Tao , Shi Yao-Jie , Lei Qian , Yu Luo-Ting
Published: April 2018

Pd(t-Bu3P)2/KOAc proved to be a good combination for one-pot synthesis of N–H phenanthridinones with up to 95% yield.
Oxidative chemical vapour deposition of a graphene oxide carbocatalyst on 3D nickel foam as a collaborative electrocatalyst towards the hydrogen evolution reaction in acidic electrolyte
Authors: Sarawutanukul Sangchai , Phattharasupakun Nutthaphon , Wutthiprom Juthaporn , Sawangphruk Montree
Published: April 2018

In this study, a graphene oxide (GO) carbocatalyst was synthesized as a thin film on a 3D Ni foam substrate (GO@Ni) by oxidative chemical vapour deposition (CVD) using methanol and water as precursors.
Tuning the optical properties of graphene quantum dots for biosensing and bioimaging
Authors: Hai Xin , Feng Ji , Chen Xuwei , Wang Jianhua
Published: April 2018

This review highlights new insights into the various strategies used to tune the optical features of graphene quantum dots, and their use as attractive and powerful probes for bio-sensing/imaging.
In situ hydrosilane reduction and preparation of gold nanoparticle–gel glass composites with nonlinear optical properties
Authors: Yu Dajiang , Sun Xingming , Chen Xin , Ma Wencan , Sun Jibin , Zhou Chuanjian , Xie Zheng , Zhou Shuyun
Published: April 2018

Gold nanoparticles were reduced in situ by a new hydrosilane reductant in organosilicon oligomer to fabricate nonlinear optical limiting materials.
Introducing optically polarizable molecules into perovskite solar cells by simultaneously enhanced spin–orbital coupling, suppressed non-radiative recombination and improved transport balance towards enhancing photovoltaic actions
Authors: Han Changfeng , Yu Haomiao , Duan Jiashun , Lu Kai , Zhang Jia , Shao Ming , Hu Bin
Published: April 2018

Introducing optically polarizable molecules into perovskite solar cells can enhance photovoltaic actions.
Supreme performance of zinc oxynitride thin film transistors via systematic control of the photo-thermal activation process
Authors: Jeong Hyun-Jun , Lee Hyun-Mo , Ok Kyung-Chul , Park Jozeph , Park Jin-Seong
Published: April 2018

Zinc oxynitride (ZnON) is a relatively novel class of material, often regarded as a promising alternative to oxide semiconductors, owing to its relatively high electron mobility and low concentration of oxygen-related defects that affect the device reliability.
Human echolocation: 2D shape discrimination using features extracted from acoustic echoes
Authors: Yu Xuelian , Thaler Lore , Baker Christopher J. , Smith Graeme E. , Zhao Linsen
Published: April 2018

Some blind humans have developed the ability to perceive their silent surrounding by using echolocation based on tongue clicks. Past research has also shown that blind echolocators can use information gained from multiple echoic ‘views’, provided through head movements, to successfully identify 2D shapes. Here, echo features that might be used by blind humans to discriminate 2D shapes are investigated. Echoes from four shapes are collected with a custom‐built acoustic radar and various features are extracted. By piecing together individual features across the measurement plane, it is found that total power and spectral centroid are two salient features for shape discrimination from multiple echoic views.
Circularly polarised patch antenna using 3D‐printed asymmetric substrate
Authors: Wang Shiyan , Zhu Lei , Wang Jianpeng , Wu Wen
Published: April 2018

A microstrip patch antenna with circular polarisation is presented by using an intrinsically asymmetric 3D‐printed substrate. Unlike conventional circularly polarised (CP) antenna, the perturbation for generating CP waves is caused by the asymmetry of substrate, where a pair of triangular air insertions is symmetrically etched in one of diagonals of the square substrate. Besides, a slot is etched on the centre of patch and parallel to its side for good impedance matching. Actually, in consideration of the fact that in 3D printing, the dimensional tolerance for dielectric is less than the one for metal, the presented approach has more superiority than the conventional methods. A prototype is fabricated and measured. Measured results are found in reasonably good agreement with the simulated ones. Stereo lithography apparatus technology is here employed in the 3D printing process.
Enhancing performance of a InGaP/GaAs VCO by means of a switching architecture
Authors: Pantoli L. , Arena S. , Cavanna T.
Published: April 2018

The introduction of a compact switching architecture in the design of a monolithic microwave integrated voltage‐controlled oscillator (VCO) is described, that is able to provide enhanced characteristics in term of both linearity and tunability. The proposed solution is applied to the design of a C‐band GaAs MMIC (monolithic microwave integrated circuit) VCO. The chip has been realised with the heterojunction bipolar transistor (HBT) HB20M technology process provided by UMS Foundry. Measurements show a relative tuning range of about 30%, an average sensitivity of about 83 MHz/V, a minimum output power of 11.4 dBm and a phase noise at 100 kHz of frequency offset from the carrier lower of −107 dBc/Hz.
Contour detection model based on neuron behaviour in primary visual cortex
Authors: Lin Chuan , Xu Guili , Cao Yijun
Published: April 2018

In the mammalian primary visual cortex, the response of the classical receptive field (CRF) to visual stimuli can be suppressed by inhibition of non‐CRF (nCRF) neurons. Although many biologically plausible models based on these centre–surround interaction properties have been proposed, most of these models have failed to account for two important behaviours of neurons in the primary visual cortex (V1). First, saturation properties of neuron response. Second, the properties of fixational eye movements (FEyeMs). In the present study, the authors proposed a biologically motivated counter detection approach based on these properties. The authors’ work is significant in that they utilised a simple threshold method to ensure that CRF responses were observed within a meaningful range, and multichannel filter bank was proposed to simulate the influence of FEyeMs on nCRF. Both methods effectively preserved object contours and inhibition isolated textures. Extensive experiments indicated that the authors’ model can preserve more object contours and suppress more textures than previous biologically based models.
Factorial analysis for ageing assessment of in‐service transformers
Authors: Wang Dongmiao , Tee Sheng Ji , Liu Qiang , Wang Zhongdong
Published: April 2018

Condition monitoring data in the form of oil test results are important for transformer ageing assessment and asset management. Analysis of variance‐based factorial analysis was demonstrated as a data mining technique for identifying the influence of different factors on transformer ageing. Using a UK oil test database of 33/11(or 6.6) kV transformers, studies were performed to assess the influence of in‐service age, manufacturer, year of manufacture, load and environment on the measured oil acidity. This methodology can reduce the workload of manually performing pairwise comparisons to understand the influence of each factor. In addition, it can also consider any interaction effect present among the factors. As a demonstration, influence of the year of manufacture on oil acidity was revealed, which was confirmed by identifying a change in design for late 1960s units and an early degradation phenomenon for late 1980s units.
Numerical simulation studies on performance, soot and NOx emissions of dual‐fuel engine fuelled with hydrogen enriched biogas mixtures
Authors: Van Ga Bui , Van Nam Tran , Thi Minh Tu Bui , Quang Trung Nguyen
Published: April 2018

This study analyses the effects of hydrogen concentration enriched biogas on indicated engine cycle work, soot and NOx emissions of dual‐fuel engine. The results show that if advance injection angle of the engine is fixed at the same value as biogas only mode operation, peak value of in‐cylinder pressure increases significantly but indicated engine cycle work is only slightly improved with an increase in hydrogen concentration. Optimum advance injection angle decreases as increasing hydrogen concentration in the fuel mixture. At a given engine speed, NOx emissions decrease with increasing equivalence ratio whereas soot emissions increase almost proportionally with the equivalence ratio. At a given equivalence ratio, NOx emission increases with the increasing hydrogen concentration in fuel mixture whereas soot emission decreases contrarily. The maximum soot peak value is obtained with slightly rich mixture at equivalence ratio of around 1.1. Lean burn mixture and high hydrogen concentration result in extremely low soot concentration. Soot emission is practically negligible at equivalence ratio of about 0.9 and 20% hydrogen concentration in mixture with biogas. As hydrogen concentration increases, the decrease of optimum advance injection angle reduces simultaneously both soot and NOx emissions.
Impact analysis of vibration on nearby municipal tunnel induced by metro running
Authors: Tang Liyun , Wang Bochao , Wu Yingming , Xi Jiami , Wu Di
Published: April 2018

For researching the effect of vibration induced by metro running to normal use of municipal tunnel, the Kunming Road Municipal Tunnel (construction) at Xi'an is taken as a background. Based on the distribution of soil layer in actually engineering and the designing parameter of metro and municipal tunnel, the finite element model of ‘metro‐soil–municipal tunnel’ is established under three different positions, and the wheel–rail force at three different speeds (36, 72, and 108 km/h) is simplified by exciting force faction. Then the numerical model is analysed by transient dynamic analysis. The results show that the vibration of municipal tunnel wall is mainly characterised by vertical vibration, which increases sharply with the metro speed improved. The vibration magnitude is greatly affected by relative position between metro and municipal tunnel: the horizontal and vertical vibration magnitude above the position between two metro tunnels is 14.6–20.8% and 55.5–74.6%, respectively, of those at the top of the metro tunnel. Some suggestions are proposed that the vibration effect induced by metro running on normal use of nearby municipal tunnel could be reduced by choosing the reasonable relative position with some corresponding measures according to the metro speed.
Design and analysis of voltage clamped bidirectional DC–DC converter for energy storage applications
Authors: Narasimharaju Beeramangalla Lakshminarasaiah , Ramanjaneya Reddy Udumula , Dogga Raveendhra
Published: April 2018

The coupled inductor (CI) bidirectional DC–DC (BDC) converters are becoming popular in energy storage applications owing to high range factor, reduced device stress and high efficient. However, the applications of CI‐BDC are limited due to the leakage energy of CI. Hence, this work proposes a voltage‐clamp (VC) CI‐BDC converter that effectively recovers the leakage energy while clamping switch turn‐off voltage spikes, thus, guard the device from high‐voltage stress. The working principle of proposed BDC converter with its characteristic waveforms and the steady‐state analysis is presented. The equivalent circuits are obtained for the each interval operation of CI‐BDC converter with voltage clamp in both boost (discharging) and buck (charging) mode. A Simulink/MATLAB‐based design is presented for the CI‐BDC converter with voltage clamp. A 60 W, prototype of proposed converter has been developed and validated experimentally with the simulation counterparts. To confirm the elimination of leakage energy of CI, the analyses of VC‐CI‐BDC converter are compared with CI‐BDC converter counterparts.
Free longitudinal vibration of a nanorod with elastic spring boundary conditions made of functionally graded material
Authors: Yayli Mustafa Özgür
Published: April 2018

The elastic spring boundary conditions play an important role in dynamical analysis of functionally graded (FG) nanorods. However, these special issues have not been properly paid attention to in the previously developed non‐local models. In this work, longitudinal vibration analysis of FG restrained nanorods is presented via non‐local elasticity theory. Two axial springs are attached to a FG nanorod at both ends. By considering the non‐local differential relations for the FG nanorod, a coefficient matrix is derived and analysed via an exact eigenvalue method. Finally, the results calculated from finite‐element method are used to validate the present method. The influence of FG index, non‐local parameter and boundary conditions on the axial frequencies of FG nanorods is discussed.
Fragmentation properties of massive protocluster gas clumps: an ALMA study
Authors: Fontani F. , Commerçon B. , Giannetti A. , Beltrán M. T. , Sánchez-Monge Á. , Testi L. , Brand J. , Tan J. C.
Published: April 2018

Fragmentation of massive dense molecular clouds is the starting point in the formation of rich clusters and massive stars. Theory and numerical simulations indicate that the population of the fragments (number, mass, diameter, and separation) resulting from the gravitational collapse of such clumps is probably regulated by the balance between the magnetic field and the other competitors of self-gravity, in particular, turbulence and protostellar feedback. We have observed 11 massive, dense, and young star-forming clumps with the Atacama Large Millimeter Array (ALMA) in the thermal dust continuum emission at ~1 mm with an angular resolution of 0.′′25 with the aim of determining their population of fragments. The targets have been selected from a sample of massive molecular clumps with limited or absent star formation activity and hence limited feedback. We find fragments on sub-arcsecond scales in 8 out of the 11 sources. The ALMA images indicate two different fragmentation modes: a dominant fragment surrounded by companions with much lower mass and smaller size, and many (≥8) fragments with a gradual change in masses and sizes. The morphologies are very different, with three sources that show filament-like distributions of the fragments, while the others have irregular geometry. On average, the largest number of fragments is found towards the warmer and more massive clumps. The warmer clumps also tend to form fragments with higher mass and larger size. To understand the role of the different physical parameters in regulating the final population of the fragments, we simulated the collapse of a massive clump of 100 and 300M⊙ with different magnetic support. The 300 M⊙ case was also run for different initial temperatures and Mach numbers
M to evaluate the separate role of each of these parameters. The simulations indicate that (1) fragmentation is inhibited when the initial turbulence is low (M ~ 3), independent of the other physical parameters. This would indicate that the number of fragments in our clumps can be explained assuming a high (M ~ 6) initial turbulence, although an initial density profile different to that assumed can play a relevant role. (2) A filamentary distribution of the fragments is favoured in a highly magnetised clump. We conclude that the clumps that show many fragments distributed in a filament-like structure are likely characterised by a strong magnetic field, while the other morphologies are also possible in a weaker magnetic field.
New capability for ozone dial profiling measurements in the troposphere and lower stratosphere from aircraft
Authors: Hair Johnathan , Hostetler Chris , Cook Anthony , Harper David , Notari Anthony , Fenn Marta , Newchurch Mike , Wang Lihua , Kuang Shi , Knepp Travis , Burton Sharon , Ferrare Richard , Butler Carolyn , Collins Jim , Nehrir Amin
Published: April 2018

Recently, we successfully demonstrated a new compact and robust ozone DIAL lidar for smaller aircraft such as the NASA B200 and the ER-2 high-altitude aircraft. This is the first NASA airborne lidar to incorporate advanced solid-state lasers to produce the required power at the required ultraviolet wavelengths, and is compact and robust enough to operate nearly autonomously on the high-altitude ER-2 aircraft. This technology development resulted in the first new NASA airborne ozone DIAL instrument in more than 15 years. The combined ozone, aerosol, and clouds measurements provide valuable information on the chemistry, radiation, and dynamics of the atmosphere. In particular, from the ER-2 it offers a unique capability to study the upper troposphere and lower stratosphere.
Remote sensing of methane emissions by combining optical similitude absorption spectroscopy (OSAS) and lidar
Authors: Galtier Sandrine , Anselmo Christophe , Welschinger Jean-Yves , Cariou Jean-Pierre , Sivignon Jean-François , Miffre Alain , Rairoux Patrick
Published: April 2018

Monitoring the emission of gases is difficult to achieve in industrial sites and in environments presenting poor infrastructures. Hence, robust methodologies should be developed and coupled to Lidar technology to allow remote sensing of gas emission. OSAS is a new methodology to evaluate gas concentration emission from spectrally integrated differential absorption measurements. Proof of concept of OSAS-Lidar for CH4 emission monitoring is here presented.
Atmospheric aerosol measurements by employing a polarization scheimpflug lidar system
Authors: Mei Liang , Guan Peng , Yang Yang
Published: April 2018

A polarization Scheimpflug lidar system based on the Scheimpflug principle has been developed by employing a compact 808-nm multimode highpower laser diode and two highly integrated CMOS sensors in Dalian University of Technology (DLUT), Dalian, China. The parallel and orthogonal polarized backscattering signal are recorded by two 45 degree tilted image sensors, respectively. Atmospheric particle measurements were carried out by employing the polarization Scheimpflug lidar system.
Characterization of high temporal resolution prr acquisition by fast comtec card: Deadtime, PRR desaturation, temperature calibration and retrieval.
Authors: Martucci Giovanni , Simeonov Valentin , Renaud Ludovic , Haefele Alexander
Published: April 2018

RAman Lidar for Meteorological Observations (RALMO) is operated at MeteoSwiss and provides continuous measurements of water vapor and temperature since 2010. While the water vapor has been acquired by a Licel acquisition system since 2008, the temperature channels have been migrated to a Fastcom P7888 acquisition system, since August 2015. We present a characterization of this new acquisition system, namely its dead-time, desaturation, temporal stability of the Pure Rotational Raman signals and the retrieval of the PRR-temperature.
Application of multiple-scattering polarization lidar for the evaluation of space-borne lidar algorithms
Authors: Okamoto Hajime , Sato Kaori , Katagiri Shuichiro , Fujikawa Masahiro , Nishizawa Tomoaki , Sugimoto Nobuo , Jin Yoshitaka , Shimizu Atsushi , Ishimoto Hiroshi
Published: April 2018

Multi-field of view multiple-scattering polarization lidar (MFMSPL) has been developed to measure enhanced backscattering and depolarization ratio from optically thick clouds. Collocated cloud radar observations and Monte Carlo simulations supported the system performance such as cloud detectability and values of depolarization ratio. The system is used to evaluate/improve algorithms for space-borne lidar such as CALIOP on CALIPSO and ATLID on EarthCARE.
An assessment of the expected quality of Aeolus Level-2B wind products
Authors: Rennie Michael P.
Published: April 2018

The ADM-Aeolus L2B horizontal line-of-sight wind products are discussed, including a brief introduction to the L2B processing methods. Realistic simulation of Aeolus followed by the Ground Segment processing chain is used to assess the expected error statistics of the L2B winds. Examples of the L2B winds simulated from realistic atmospheric cases are discussed. The aim of the paper is to give potential users an impression of the expected characteristics of Aeolus mission’s main product.
Optical properties of an industrial fire observed with a ground based N2-Raman lidar over the Paris area
Authors: Shang Xiaoxia , Chazette Patrick , Totems Julien
Published: April 2018

This paper presents the first, to our knowledge, lidar measurement of an industrial fire plume, which covered the north of the Paris area on 17th April 2015. The fire started in a textile warehouse and rapidly spread by emitting large quantities of aerosols into the low troposphere. A ground based N2-Raman lidar performed continuous measurements during this event. Vertical profiles of the aerosol extinction coefficient, depolarization and lidar ratio are derived. A Monte Carlo algorithm was used to assess the uncertainties on the optical parameters, and to evaluate lidar inversion methods.
Validation of the TOLNet lidars during SCOOP (Southern California Ozone Observation Project)
Authors: Leblanc Thierry , Granados-Munoz Maria-Jose , Strawbridge Kevin , Senff Chris , Langford Andy , Berkoff Tim , Gronoff Guillaume , DeYoung Russel , Carion Bill , Chen G. , Sullivan John , McGee Tom , Jonhson M. , Kuang S. , Newchurch Mike
Published: April 2018

Five TOLNet lidars participated to a validation campaign at the JPL-Table Mountain Facility, CA in August 2016. All lidars agreed within ±10% of each other and within ±7% of the ozonesondes. Centralized data processing was used to compare the uncertainty budgets. The results highlight the TOLNet potential to address science questions ranging from boundary layer processes to long range transport. TOLNet can now be seen as a robust network for use in field campaigns and long term monitoring.
Long term lidar measurements of aerosol properties over thessaloniki
Authors: Siomos Nikolaos , Voudouri Kalliopi A. , Giannakaki Eleni , Amiridis Vasilis , Filioglou Maria , Papayannis Alexandros , Balis Dimitris S.
Published: April 2018

In this study we present some first results on the potential of 15 years of lidar measurements over the lidar station of Thessaloniki to compile a climatology of the aerosol properties for the period 2001-2015. This is examined on a monthly, seasonal and annual basis. Both the profile structure and the columnar properties of the aerosol extinction and backscatter products are examined. The results are compared for consistency against co-located sunphotometer measurements.
Refinement of the CALIOP cloud mask algorithm
Authors: Katagiri Shuichiro , Sato Kaori , Ohta Kohei , Okamoto Hajime
Published: April 2018

A modified cloud mask algorithm was applied to the CALIOP data to have more ability to detect the clouds in the lower atmosphere. In this algorithm, we also adopt the fully attenuation discrimination and the remain noise estimation using the data obtained at an altitude of 40 km to avoid contamination of stratospheric aerosols. The new cloud mask shows an increase in the lower cloud fraction. Comparison of the results to the data observed with a PML ground observation was also made.
Water vapour inter-comparison effort in the framework of the hydrological cycle in the mediterranean experiment – special observation period (hymex-sop1)
Authors: Summa Donato , Di Girolamo Paolo , Flamant Cyrille , De Rosa Benedetto , Cacciani Marco , Stelitano Dario
Published: April 2018

Accurate measurements of the vertical profiles of water vapour are of paramount importance for most key areas of atmospheric sciences. A comprehensive inter-comparison between different remote sensing and in-situ sensors has been carried out in the frame work of the first Special Observing Period of the Hydrological cycle in the Mediterranean Experiment for the purpose of obtaining accurate error estimates for these sensors. The inter-comparison involves a ground-based Raman lidar (BASIL), an airborne DIAL (LEANDRE2), a microwave radiometer, radiosondes and aircraft in-situ sensors.
ACTRIS Aerosol, Clouds and Trace Gases Research Infrastructure
Authors: Pappalardo Gelsomina
Published: April 2018

The Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS) is a distributed infrastructure dedicated to high-quality observation of aerosols, clouds, trace gases and exploration of their interactions. It will deliver precision data, services and procedures regarding the 4D variability of clouds, short-lived atmospheric species and the physical, optical and chemical properties of aerosols to improve the current capacity to analyse, understand and predict past, current and future evolution of the atmospheric environment.