bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Mumiyo Deposits From East Antarctica as Archives for the Late Quaternary Environmental and Climatic History
Authors: Berg S. , Melles M. , Hermichen W.‐D. , McClymont E. L. , Bentley M. J. , Hodgson D. A. , Kuhn G.
Published: December 2018

Mumiyo deposits form in the vicinity of snow petrel (Pagodroma nivea) nesting sites and consist of fossil stomach oil (mumiyo), guano, and minerogenic material. Here we evaluate mumiyo deposits from the inland mountain ranges of central Dronning Maud Land as high‐resolution archives for paleoenvironmental reconstructions in Antarctica. Investigation of internal structures and chemical composition shows that the lamination reflects progressive sedimentation, despite the irregular outer morphology of the deposits. Detailed radiocarbon analysis demonstrates that stratigraphies are intact: 14C ages become successively younger upwards in the deposits. Fatty acid and n‐alcohol composition was determined on samples from eight mumiyo deposits. Dominance of low molecular weight compounds (C14 to C18) points to a dietary signal; however, the relatively low proportions of unsaturated compounds compared to fresh stomach oils indicates some postdepositional degradation. We found marine diatoms in the mumiyo, which potentially provide a proxy for sea ice conditions in the foraging habitat of the petrels. Age ranges of the investigated deposits suggest occupation of the analyzed sites by snow petrels from 17 ka to >58 ka. Changes in deposition rates point to higher occupation frequency in Petermann Range from 46 to 42 ka compared to the late marine isotope stage 3 and the Last Glacial Maximum.
A Preliminary Risk Assessment of Geomagnetically Induced Currents over the Italian Territory
Authors: Tozzi R. , De Michelis P. , Coco I. , Giannattasio F.
Published: December 2018

Geomagnetically induced currents (GICs), occurring as a result of space weather events, represent a hazard for the secure and safe operation of electrical power grids and oil/gas pipelines. The most exposed countries are those at high latitudes where, in the past, the occurrence of intense GICs has seriously damaged part of their power networks. However, very powerful space weather events have resulted in intense GICs also at middle and low latitudes. The GIC index is a proxy of the geoelectric field, and it can be estimated straightforwardly from magnetic observatory data. In this work, the GIC index is computed to investigate the possible impact of space weather events on the Italian territory. We first calculate the GIC index using data from the magnetic observatories of Castello Tesino, Duronia, and Lampedusa, together covering the whole Italian latitudinal extension, and show its behavior during the 2015 St. Patrick's day storm. Then, we consider measurements from the two longest running Italian magnetic observatories, that is, Castello Tesino and L'Aquila, and estimate the GIC index over more than 20 years of observations. A preliminary characterization of the general risk to which the Italian power grid network is exposed is given. Results show that during periods of high magnetic activity, potentially detrimental GICs could flow through the power network, especially at the highest Italian latitudes that are characterized by a low conductivity lithosphere.
Dysfunctional autophagy induced by the pro-apoptotic natural compound climacostol in tumour cells
Authors: Zecchini Silvia , Proietti Serafini Francesca , Catalani Elisabetta , Giovarelli Matteo , Coazzoli Marco , Di Renzo Ilaria , De Palma Clara , Perrotta Cristiana , Clementi Emilio , Buonanno Federico , Ortenzi Claudio , Marcantoni Enrico , Taddei Anna Rita , Picchietti Simona , Fausto Anna Maria , Cervia Davide
Published: December 2018

Autophagy occurs at a basal level in all eukaryotic cells and may support cell survival or activate death pathways. Due to its pathophysiologic significance, the autophagic machinery is a promising target for the development of multiple approaches for anti-neoplastic agents. We have recently described the cytotoxic and pro-apoptotic mechanisms, targeting the tumour suppressor p53, of climacostol, a natural product of the ciliated protozoan Climacostomum virens. We report here on how climacostol regulates autophagy and the involvement of p53-dependent mechanisms. Using both in vitro and in vivo techniques, we show that climacostol potently and selectively impairs autophagy in multiple tumour cells that are committed to die by apoptosis. In particular, in B16-F10 mouse melanomas climacostol exerts a marked and sustained accumulation of autophagosomes as the result of dysfunctional autophagic degradation. We also provide mechanistic insights showing that climacostol affects autophagosome turnover via p53-AMPK axis, although the mTOR pathway unrelated to p53 levels plays a role. In particular, climacostol activated p53 inducing the upregulation of p53 protein levels in the nuclei through effects on p53 stability at translational level, as for instance the phosphorylation at Ser15 site. Noteworthy, AMPKα activation was the major responsible of climacostol-induced autophagy disruption in the absence of a key role regulating cell death, thus indicating that climacostol effects on autophagy and apoptosis are two separate events, which may act independently on life/death decisions of the cell. Since the activation of p53 system is at the molecular crossroad regulating both the anti-autophagic action of climacostol and its role in the apoptosis induction, it might be important to explore the dual targeting of autophagy and apoptosis with agents acting on p53 for the selective killing of tumours. These findings also suggest the efficacy of ciliate bioactive molecules to identify novel lead compounds in drug discovery and development.
Ruthenium(ii)-catalyzed electrooxidative [4+2] annulation of benzylic alcohols with internal alkynes: entry to isocoumarins
Authors: Luo Mu-Jia , Hu Ming , Song Ren-Jie , He De-Liang , Li Jin-Heng
Published: December 2018

Ruthenium(ii)-catalyzed electrooxidative [4+2] annulation with internal alkynes using benzylic alcohols as weakly directing group precursors is presented.
CTAB-triggered Ag aggregates for reproducible SERS analysis of urinary polycyclic aromatic hydrocarbon metabolites
Authors: Gao Ye , Li Linfang , Zhang Xue , Wang Xinnan , Ji Wei , Zhao Jianzhang , Ozaki Yukihiro
Published: December 2018

We have demonstrated a simple SERS assay for urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) with high sensitivity and reproducibility.
An immuno-potentiating vehicle made of mesoporous silica-zinc oxide micro-rosettes with enhanced doxorubicin loading for combined chemoimmunotherapy
Authors: Qian Guowen , Wang Xiupeng , Li Xia , Ito Atsuo , Sogo Yu , Ye Jiandong
Published: December 2018

MS-Zn-DOX in combination with PIC not only significantly inhibit tumor growth, but also effectively rejects tumor metastasis in vivo, obviously improving CD4+ and CD8+ T cell populations and IFN-γ secretion in splenocytes of mice.
Photo-regulatable DNA isothermal amplification by template-mediated ligation
Authors: Cheng Bohao , Kashida Hiromu , Shimada Naohiko , Maruyama Atsushi , Asanuma Hiroyuki
Published: December 2018

Alternating irradiation with UV and visible light promotes controllable amplification of DNA under isothermal conditions.
The impact on the ring related vibrational frequencies of pyridine of hydrogen bonds with haloforms – a topology perspective
Authors: Benassi Enrico , Akhmetova Kamila , Fan Haiyan
Published: December 2018

An intermolecular ring structure is identified for the hydrogen bonding system of pyridine and haloforms.
The optical absorption spectra of spontaneously electrical solids: the case of nitrous oxide
Authors: Cassidy Andrew , James Rachel L. , Dawes Anita , Lasne Jérôme , Field David
Published: December 2018

Mud flats, Fejø, Denmark: a 2D representation of defect-free regions in a molecular crystal that can support Wannier–Mott excitons.
Modeling of a fast-response magnetic-sensitive hydrogel for dynamic control of microfluidic flow
Authors: Liu Qimin , Li Hua , Lam K. Y.
Published: December 2018

A magnetic-sensitive hydrogel-based microfluidic system is designed numerically for replicating various physiological and pathological conditions in the human body.
Spin trapping and flipping in FeCO through relativistic electron dynamics
Authors: Ulusoy Inga S. , Wilson Angela K.
Published: December 2018

Electron dynamics of spin-state conversion compounds. Excited triplet and quintet states are significantly spin-mixed – transitions can be induced easily: “channels” that enable spin flipping. The lowest-lying quintet state acts as a “sink”: exhibits weak coupling.
In situ XPS analysis of the atomic layer deposition of aluminium oxide on titanium dioxide
Authors: Temperton Robert H. , Gibson Andrew , O'Shea James N.
Published: December 2018

Ultra-thin aluminium oxide was grown on a rutile titanium dioxide surface by atomic layer deposition using trimethylaluminium and water precursors. XPS measurements were made during the growth process at near-ambient pressures.
Photofragment spin-polarization measurements via magnetization quantum beats: dynamics of DI photodissociation
Authors: Sofikitis Dimitris , Kannis Chrysovalantis S. , Boulogiannis Gregoris K. , Katsoprinakis Georgios E. , Rakitzis T. Peter
Published: December 2018

We report the electron-spin polarization of D atoms from the photodissociation of DI, at 213 nm and 266 nm, by measuring the magnetization quantum beats of the D atoms with a pick-up coil.
Recent progress in covalent organic framework thin films: fabrications, applications and perspectives
Authors: Wang Han , Zeng Zhuotong , Xu Piao , Li Lianshan , Zeng Guangming , Xiao Rong , Tang Zhiyong , Huang Danlian , Tang Lin , Lai Cui , Jiang Danni , Liu Yang , Yi Huan , Qin Lei , Ye Shujing , Ren Xiaoya , Tang Wangwang
Published: December 2018

This review presents a comprehensive summary of the synthesis and applications of covalent organic framework thin films.
Selecting and identifying gas-phase protonation isomers of nicotineH+ using combined laser, ion mobility and mass spectrometry techniques
Authors: Marlton Samuel J. P. , McKinnon Benjamin I. , Ucur Boris , Maccarone Alan T. , Donald William A. , Blanksby Stephen J. , Trevitt Adam J.
Published: December 2018

Protonation isomers of gas-phase nicotineH+ are separated and assigned using a combination of FAIMS and UV photodissociation action spectroscopy.
Novel carbon based bioactive nanocomposites of aniline/indole copolymer for removal of cationic dyes from aqueous solution: kinetics and isotherms
Authors: Rouhi Mona , Lakouraj Moslem Mansour , Tashakkorian Hamed , Hasantabar Vahid
Published: December 2018

In this study, a copolymer of aniline and indole P(ANI-co-IN) and its nanocomposites based on graphene oxide (GO) and functional carbon nanotubes (CNT-COOH) were synthesized by heterogeneous emulsion polymerization.
Nickel-catalyzed cross-coupling of O,N-chelated diarylborinates with aryl chlorides and mesylates
Authors: Ren Chao , Zeng Jingshu , Zou Gang
Published: December 2018

Practical nickel catalysis for efficient cross-coupling of O,N-chelated diarylborinates with aryl chlorides and mesylates based on air-stable yet readily activated organonickel precursor, trans-NiCl(Ph)(PPh3)2, and sterically unsymmetrical N-heterocyclic carbene in situ generated from imidazolium precursor with trihydrate potassium phosphate in toluene.
A systematic study of the synthesis of cesium lead halide nanocrystals: does Cs4PbBr6 or CsPbBr3 form?
Authors: Jing Qiang , Xu Yue , Su Yucong , Xing Xing , Lu Zhenda
Published: December 2018

An amine-free method is used to systematically investigate the role of Cs, Pb and Br in hot-injection synthesis.
Efficient base-free direct oxidation of glucose to gluconic acid over TiO2-supported gold clusters
Authors: Guo Song , Fang Qihua , Li Zhimin , Zhang Jia , Zhang Junying , Li Gao
Published: December 2018

The transformation of renewable natural resources is an appealing and sustainable protocol to minimize fossil fuel consumption.
Investigation of the magnetosome biomineralization in magnetotactic bacteria using graphene liquid cell – transmission electron microscopy
Authors: Firlar Emre , Ouy Meagan , Bogdanowicz Agata , Covnot Leigha , Song Boao , Nadkarni Yash , Shahbazian-Yassar Reza , Shokuhfar Tolou
Published: December 2018

Magnetosome biomineralization in magnetotactic bacteria was observed by keeping the bacteria alive using graphene liquid cell transmission electron microscopy.
The discovery and enhanced properties of trichain lipids in lipopolyplex gene delivery systems
Authors: Mohammadi Atefeh , Kudsiova Laila , Mustapa M. Firouz Mohd , Campbell Frederick , Vlaho Danielle , Welser Katharina , Story Harriet , Tagalakis Aristides D. , Hart Stephen L. , Barlow David J. , Tabor Alethea B. , Lawrence M. Jayne , Hailes Helen C.
Published: December 2018

Novel trichain lipids have been identified with enhanced transfection properties in lipopolyplexes.
Bicyclic acetals: biological relevance, scaffold analysis, and applications in diversity-oriented synthesis
Authors: Lenci Elena , Menchi Gloria , Saldívar-Gonzalez Fernanda I. , Medina-Franco José L. , Trabocchi Andrea
Published: December 2018

The chemoinformatics analysis of fused, spiro, and bridged bicyclic acetals is instrumental for the DOS of natural product-inspired molecular collections.
Intermolecular oxidative radical fluoroalkylfluorosulfonylation of unactivated alkenes with (fluoroalkyl)trimethylsilane, silver fluoride, sulfur dioxide and N-fluorobenzenesulfonimide
Authors: Lin Qiongzhen , Liu Yongan , Xiao Zhiwei , Zheng Liping , Zhou Xiumiao , Guo Yong , Chen Qing-Yun , Zheng Changge , Liu Chao
Published: December 2018

Reaction of unactivated alkenes affords various fluoroalkyl-containing alkyl sulfonyl fluorides with good functional group tolerance under mild conditions.
A cubic room temperature polymorph of thermoelectric TAGS-85
Authors: Kumar Anil , Vermeulen Paul A. , Kooi Bart J. , Rao Jiancun , Schwarzmüller Stefan , Oeckler Oliver , Blake Graeme R.
Published: December 2018

A new cubic polymorph of thermoelectric TAGS-85 irreversibly transforms to a trigonal layered phase on heating, with precipitation of Ag8GeTe6.
The performance and associated mechanisms of carbon transformation (PHAs, polyhydroxyalkanoates) and nitrogen removal for landfill leachate treatment in a sequencing batch biofilm reactor (SBBR)
Authors: Yin Wenjun , Wang Kai , Xu Jingtao , Wu Daoji , Zhao Congcong
Published: December 2018

A modified sequencing batch biofilm reactor (SBBR, adding a pre-anoxic phase before the aeration phase) was used to treat landfill leachate.
The influence of phosphine ligand substituted [2Fe2S] model complexes as electro-catalyst on proton reduction
Authors: Zhang Xia , Ma Xiaoyuan , Zhang Tianyong , Li Bin , Jiang Shuang , Zhang Guanghui , Hai Li , Wang Jingchao , Shao Xiao
Published: December 2018

To probe the influence of phosphine ligand substitution on the well-known [2Fe2S] model, two new [FeFe]-hydrogenase model complexes with the phosphine ligands, PMe3 or P(CH3O)3, were synthesized.
Preparation, structure identification and the anti-photoaging activity of peptide fraction OP-Ia from Ostrea rivularis
Authors: Ye Yuhui , You Lijun , Deng Qihui , Li Xiong , Zhao Mouming
Published: December 2018

OP-Ia could reduce ROS generation and cell viability declination induced by UV, and downregulate the expressions of IL-1β, IL-8, c-Jun, c-Fos, p65 and p38 genes.
Advice from the Scientific Advisory Board of the Organisation for the Prohibition of Chemical Weapons on riot control agents in connection to the Chemical Weapons Convention
Authors: Timperley Christopher M. , Forman Jonathan E. , Åas Pal , Abdollahi Mohammad , Benachour Djafer , Al-Amri Abdullah Saeed , Baulig Augustin , Becker-Arnold Renate , Borrett Veronica , Cariño Flerida A. , Curty Christophe , Gonzalez David , Geist Michael , Kane William , Kovarik Zrinka , Martínez-Álvarez Roberto , Mikulak Robert , Fusaro Mourão Nicia Maria , Neffe Slawomir , De Souza Nogueira Evandro , Ramasami Ponnadurai , Raza Syed K. , Rubaylo Valentin , Saeed Ahmed E. M. , Takeuchi Koji , Tang Cheng , Trifirò Ferruccio , Mauritz van Straten Francois , Suárez Alejandra G. , Waqar Farhat , Vanninen Paula S. , Zafar-Uz-Zaman Mohammad , Vučinić Slavica , Zaitsev Volodymyr , Zina Mongia Saïd , Holen Stian , Izzati Fauzia Nurul
Published: December 2018

Chemicals that meet the criteria of a riot control agent as defined by the Chemical Weapons Convention (an international chemical disarmament and non-proliferation treaty) are reviewed by the Scientific Advisory Board of the Organisation for the Prohibition of Chemical Weapons.
Synthesis and structural features of thiophene-fused analogues of warped nanographene and quintuple helicene
Authors: Lin Hsing-An , Kato Kenta , Segawa Yasutomo , Scott Lawrence T. , Itami Kenichiro
Published: December 2018

Thiophene-fused analogues of warped nanographene (WNG) and quintuple helicene (QH) were synthesized via a three-step π-extension of corannulene.
Colloid supported lipid bilayers for self-assembly
Authors: Rinaldin Melissa , Verweij Ruben W. , Chakraborty Indrani , Kraft Daniela J.
Published: December 2018

Careful tuning of the experimental parameters involved in preparing colloid supported lipid bilayers enables the self-assembly of flexible structures.
Enabling room-temperature processed highly efficient and stable 2D Ruddlesden–Popper perovskite solar cells with eliminated hysteresis by synergistic exploitation of additives and solvents
Authors: Yu Shuang , Yan Yajie , Chen Yani , Chábera Pavel , Zheng Kaibo , Liang Ziqi
Published: December 2018

In 2D RP perovskites, two competitive processes of NH4Cl and DMSO additions reach a delicate balance in dual-treated devices, which deliver a maximum PCE up to 13.41% with excellent air-stability and eliminated hysteresis.
Polymeric iodobismuthates {[Bi3I10]} and {[BiI4]} with N-heterocyclic cations: promising perovskite-like photoactive materials for electronic devices
Authors: Usoltsev Andrey N. , Elshobaki Moneim , Adonin Sergey A. , Frolova Lyubov A. , Derzhavskaya Tatiyana , Abramov Pavel A. , Anokhin Denis V. , Korolkov Ilya V. , Luchkin Sergey Yu. , Dremova Nadezhda N. , Stevenson Keith J. , Sokolov Maxim N. , Fedin Vladimir P. , Troshin Pavel A.
Published: December 2018

Structurally different complex bismuth iodides with 1D anionic frameworks were designed and explored as semiconductor materials for photovoltaic devices.
Photoinduced synthesis of Bi2O3 nanotubes based on oriented attachment
Authors: Qiu Yaming , Zhang Lei , Liu Lingmei , Lin Cong , Xu Le , Li Jian , Yuan Youyou , Du Xin , Han Yu , Sun Junliang
Published: December 2018

The photoinduced synthesis of ultrafine Bi2O3 nanotubes from amorphous bismuth hydroxide nanoparticles at room temperature.
Unexpectedly high cross-plane thermoelectric performance of layered carbon nitrides
Authors: Ding Zhidong , An Meng , Mo Shenqiu , Yu Xiaoxiang , Jin Zelin , Liao Yuxuan , Esfarjani Keivan , Lü Jing-Tao , Shiomi Junichiro , Yang Nuo
Published: December 2018

A strategy to increase the efficiency of layered organic thermoelectric material is proposed by utilizing the overlap of pz orbitals.
Correction: High thermoelectric performance in complex phosphides enabled by stereochemically active lone pair electrons
Authors: Shen Xingchen , Xia Yi , Wang Guiwen , Zhou Fei , Ozolins Vidvuds , Lu Xu , Wang Guoyu , Zhou Xiaoyuan
Published: December 2018

Correction for ‘High thermoelectric performance in complex phosphides enabled by stereochemically active lone pair electrons’ by Xingchen Shen et al., J. Mater. Chem. A, 2018, 6, 24877–24884.
Prediction of new ZnS–CaS alloys with anomalous electronic properties
Authors: Gao Jie , Duan Yifeng , Zhao Changming , Liu Wenjie , Dong Haiming , Zhang Dekun , Dong Huafeng
Published: December 2018

ZnS–CaS alloys have great potential for applications in ultraviolet optoelectronic devices due to their large and tunable band gaps.
Monitoring the crystal orientation of black-arsenic via vibrational spectra
Authors: Kandemir A. , Iyikanat F. , Sahin H.
Published: December 2018

In this study, the structural, mechanical, and vibrational properties of a recently discovered anisotropic ultra-thin material, black-arsenic (b-As), are investigated by using density functional theory.
Mechanical stress distribution and risk assessment of 110 kV GIS insulator considering Al2O3 settlement
Authors: Liang Hucheng , Du Boxue , Li Jin , Wang Zehua
Published: December 2018

The growing application of gas insulated switchgear (GIS) in electric power system asks for higher reliability of epoxy (EP) insulators, thus it is important to seek effective methods to improve the operating reliability of GIS insulators. On the basis of the 110 kV GIS insulator, this study studied the aluminium oxide (Al2O3) settlement in the curing process and the stress distribution of the horizontally laid GIS. Besides, the risk coefficient was defined to evaluate the operating reliability of insulators laid by different methods (I–V). Some conclusions are shown below: the Al2O3 settlement in the curing process causes the insulator density to have a large variation from 2.13 to 2.32 g/cm3. The Al2O3 content has a great influence on the mechanical performances of EP/Al2O3system. The first principle stress is localised on the upper interface between the insulator and the conductor, which is the main threat to the mechanical damage of insulator. The laying method V appears to be optimal with a pretty low risk coefficient of 31.5. In actual application, for the horizontally laid GIS, the insulator should be laid with the mould gate downward to improve its mechanical reliability.
Multi‐level bus voltage compensation of droop control with enhanced load‐sharing capability for DC microgrid
Authors: Liu Sucheng , Li Zhongpeng , Liu Wenjie , Liu Xiaodong
Published: December 2018

In DC microgrid, droop control is an essential part of local primary level in hierarchical control to perform load‐sharing and plug‐and‐play function. The main problem with droop control is that better load sharing is achieved at the cost of higher bus voltage drop, which could even be worse when cable resistance is considered. To solve this problem, a multi‐level bus voltage compensation of droop control (MLBVC‐DC) for DC microgrid with enhanced load‐sharing capability is proposed. With high enough droop gain to ensure load‐sharing accuracy, the produced bus voltage drop will be compensated with multi‐level feedforward to the reference bus voltage of DC microgrid according to different load regions. Also, the problem with the piecewise droop at load current setting points is solved by hysteretic control and Control Area Network (CAN) communication. Simulation and experimental results verify the proposed MLBVC‐DC strategy.
Effects of humidity on variation of negative corona‐generated space charge in rod to plane electrode
Authors: Bian Xingming , He Zichen , Zhu JunYu , Pi Xinan , Wan Shuwei , Qi Lei
Published: December 2018

The variation of negative corona‐generated space charge related to the humidity has been systematically calculated and analysed by computational approaches. A negative fluid model in which the humidity could be adjusted was established to calculate the charged‐particle density and electric field under different applied voltages. The continuity equations were solved by a flux‐corrected transport algorithm and the Poisson equation was computed by the successive over relaxation method. The variations of important parameters due to humidity were discussed including ionisation coefficient, attachment coefficient, effective ionisation coefficient and electron generation rate. Each of them increases with the rise in relative humidity (RH). The particles densities of electrons, positive ions and negative ions when RH is 50, 80 and 90% were also calculated, respectively, which decreased as RH increased.
Distributed control strategy of hybrid energy storage system in the DC microgrid
Authors: Teng Changpeng , Wang Yubin , Wang Fan , Zhang Fengyi
Published: December 2018

In a DC microgrid, because the output of renewable energy such as photovoltaic is intermittent, hybrid energy storage system (HESS) combining ultracapacitors and batteries is usually used to solve this issue. According to the characteristics of ultracapacitors and batteries, the low‐frequency power fluctuations are assigned to batteries, while the high‐frequency power fluctuations are assigned to ultracapacitors. When considering an ultracapacitor group, state‐of‐charge (SoC) of the ultracapacitors will be unbalanced between each other, on account of the differences of initial states or attributes. A novel distributed control method is proposed in this study. In general, ultracapacitors control the DC bus voltage and batteries control SoC of the ultracapacitors. Additionally, the distributed control adds the difference between one ultracapacitor's SoC and the average SoC of the ultracapacitor group to its current control loop. As a result, the dynamic stability of SoC among the ultracapacitors can be achieved, and the issues of overcharging and/or over discharging of the ultracapacitors can be avoided. At last, the effectiveness of the proposed control strategy is validated by the simulation model built in MATLAB/Simulink.
Study on electric field distribution characteristics of the maintenance area when UHV AC transmission line crossing 220 kV tower
Authors: Huo Feng , Lu Wei , Qiu Zhibin , Huang Daochun , Huang Congpeng
Published: December 2018

With the rapid development of China's power grid, it is becoming increasingly common that the multi‐circuit overhead transmission lines cross over each other. It is important to design the lines' configuration reasonably and evaluate whether the power‐frequency electric field meets the national standard. In order to analyse the electric field distribution in the maintenance area of the 220 kV tower with an overhead 1000 kV UHV AC double circuit transmission line, a three‐dimensional finite element model of the crossing tower and transmission line was established. The influences of the crossing angle, span height and offset distance on the electric field distribution in the maintenance area of the lower tower and the line worker body surface electric field were analysed. The results show that the maximum electric field strength of the tower will increase 28.7% when the cross‐angle decreases from 90° to 30°, and the impact of span height on the electric field distribution is much smaller at 90° than that at 30°. At 60°, when the crossing height is 16 m, the electric field strength on the worker's body surface is much less than the limiting value.
Application of UPFC to mitigate SSR in series‐compensated wind farms
Authors: Jiang Hongli , Song Ruihua , Du Ning , Zhou Peipeng , Zheng Bin , Han Yanan , Yang Daye
Published: December 2018

Flexible AC transmission systems have shown effective functionalities in promoting the system operation security and service reliability. Facing with series‐compensated lines, subsynchronous resonance (SSR) may jeopardise the stability and mechanical facilities. The control strategy and simulation model of a unified power flow controller (UPFC) based on the dq decoupling control are deduced and constructed. Considering the impacts of grid‐connected wind farms, SSR characteristics of the series‐compensated system with UPFC are studied by the complex torque coefficient method and time‐domain simulation. The results verify the capability of UPFC in attenuating SSR in wind farm integrations by utilising subsynchronous damping controllers coordinated with UPFC's main controllers. It also suggests that the shunt transformer−converter has a slight effect on SSR, whereas the series transformer−converter affects the system resonance characteristics significantly. Simulations are carried out on a typical power system model integrated with wind turbines.
Seismic evaluation of ±800 kV UHVDC disconnect switch by shake table test
Authors: Wen Jiayi , Xie Qiang
Published: December 2018

Disconnect switches, the widely used electrical substation apparatuses, however, were severely damaged in several earthquakes, causing huge economic losses. Disconnect switches with higher voltage are more vulnerable to earthquake for their great height and flexibility. The interaction between posts and blades might magnify the seismic responses, which is not fully understood and deserves further investigations. Therefore, a full‐scale shake table test on a new‐style latticed ±800 kV ultra‐high voltage direct current disconnect switch was carried out to evaluate its dynamic properties and seismic responses. Two different operational conditions with the main blade open and closed were tested, respectively. Interaction between posts and blades was studied via acceleration amplification factors and the spectrum analysis. The test result indicates interaction only exists in the length direction, and will amplify seismic responses of the post with the main blade, while reduce those of the post with the fixed contact. Moreover, the seismic responses of specimen are smaller than those in previous studies, suggesting the latticed structural form alleviate the negative effects induced by the great height and flexibility, and is helpful for structural design of disconnect switches.
Interaction influence of harmonics in MIDC transmission systems
Authors: Ling Wang , Dong Chen , Yinglin Xue , Fangjie Wu
Published: December 2018

Owing to the particular distribution of energy and load, the high‐voltage direct current transmission system has been greatly developed in China. A number of areas have formed the multi‐infeed direct current (MIDC) transmission systems. In MIDC transmission systems, the electrical distance between the inverter stations is close and the coupling effect is strong, therefore, the interaction influence of harmonics is complex. In order to analyse this complex interaction influence, this study first introduces the influence factors multi‐infeed influence factors of power (MIIF‐Pd) and multi‐infeed total harmonic voltage distortion (MITHDu), which are used to describe the interaction influence degree of harmonics between inverter stations. Then based on the Shanghai power grid, a simulation model of the MIDC transmission systems was built in PSCAD/EMTDC, and the interaction influence degree of harmonics in MIDC transmission systems was studied in the case of large disturbance and small disturbance exists in the inverter stations. The results show that the interaction influence of harmonics between inverter stations is related to the electrical distance, the style of disturbance, transmission power and so on. Meanwhile, the disturbance on a commutation bus mainly leads to the increase of the harmonic distortion rate in this inverter station, and has less influence on the other stations.
Voltage regulation strategy of AC distribution network based on distributed PV grid‐connected inverter
Authors: Tong Xiangqian , Zhong Minghang , Zhang Xiaoqing , Deng Jun , Zhang Zhihua
Published: December 2018

The distribution network connected with photovoltaic (PV) power generation may show high voltage under strong light and low voltage under weak light. The influence of distributed PV generation on the grid voltage profile is analysed first, and then, the sensitivity of the grid voltage to the PV inverter output power is deduced. Aiming at overhead line distribution network, the local voltage regulation strategy based on the power control of the grid‐connected PV inverter is proposed. The PV inverter works under the maximum power point tracking (MPPT) mode with unity power factor when the grid voltage is at the normal level. However, when the voltage is higher than its upper limit, the grid‐connected PV inverter will be co‐ordinately controlled to output limited active power and necessary reactive power to restrain the line voltage. Also, when the voltage is below than the lower limit, only the reactive power of the grid‐connected PV inverter was controlled to sustain the line voltage, and the reactive power is no more than the residual capacity of the grid‐connected PV inverter operated in the MPPT mode. Simulation and results show that the voltage quality of the distribution network with PV generation is improved by using the voltage regulation strategy presented in this study.
Comparison of the excess mass around CFHTLenS galaxy-pairs to predictions from a semi-analytic model using galaxy-galaxy-galaxy lensing
Authors: Simon P. , Saghiha H. , Hilbert S. , Schneider P. , Boever C. , Wright A. H.
Published: December 2018

The matter environment of galaxies is connected to the physics of galaxy formation and evolution. In particular, the average matter distribution around galaxy pairs is a strong test for galaxy models. Utilising galaxy-galaxy-galaxy lensing as a direct probe, we map out the distribution of correlated surface mass-density around galaxy pairs in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). We have compared, for the first time, these so-called excess mass maps to predictions provided by a recent semi-analytic model, which is implanted within the dark-matter Millennium Simulation. We analysed galaxies with stellar masses between 109 − 1011 M⊙ in two photometric redshift bins, for lens redshifts z ≲ 0.6. The projected separation of the galaxy pairs ranges between 170 − 300 h−1 kpc, thereby focusing on pairs inside groups and clusters. To allow us a better interpretation of the maps, we discuss the impact of chance pairs, that is galaxy pairs that appear close to each other in projection only. We have introduced an alternative correlation map that is less affected by projection effects but has a lower signal-to-noise ratio. Our tests with synthetic data demonstrate that the patterns observed in both types of maps are essentially produced by correlated pairs which are close in redshift (Δz ≲ 5 × 10−3). We also verify the excellent accuracy of the map estimators. In an application to the galaxy samples in the CFHTLenS, we obtain a 3σ − 6σ significant detection of the excess mass and an overall good agreement with the galaxy model predictions. There are, however, a few localised spots in the maps where the observational data disagrees with the model predictions on a ≈3.5σ confidence level. Although we have no strong indications for systematic errors in the maps, this disagreement may be related to the residual B-mode pattern observed in the average of all maps. Alternatively, misaligned galaxy pairs inside dark matter halos or lensing by a misaligned distribution of the intra-cluster gas might also cause the unanticipated bulge in the distribution of the excess mass between lens pairs.
The formation of solar-system analogs in young star clusters
Authors: Portegies Zwart S.
Published: December 2018

The solar system was once rich in the short-lived radionuclide (SLR) 26Al but poor in 60Fe. Several models have been proposed to explain these anomalous abundances in SLRs, but none has been set within a self-consistent framework of the evolution of the solar system and its birth environment. The anomalous abundance in 26Al may have originated from the accreted material in the wind of a massive ≳20 M⊙ Wolf-Rayet star, but the star could also have been a member of the parental star-cluster instead of an interloper or an older generation that enriched the proto-solar nebula. The protoplanetary disk at that time was already truncated around the Kuiper-cliff (at 45 au) by encounters with other cluster members before it was enriched by the wind of the nearby Wolf-Rayet star. The supernova explosion of a nearby star, possibly but not necessarily the exploding Wolf-Rayet star, heated the disk to ≳1500 K, melting small dust grains and causing the encapsulation and preservation of 26Al in vitreous droplets. This supernova, and possibly several others, caused a further abrasion of the disk and led to its observed tilt of 5.6 ± 1.2° with respect to the equatorial plane of the Sun. The abundance of 60Fe originates from a supernova shell, but its preservation results from a subsequent supernova. At least two supernovae are needed (one to deliver 60Fe and one to preserve it in the disk) to explain the observed characteristics of the solar system. The most probable birth cluster therefore has N = 2500 ± 300 stars and a radius of rvir = 0.75 ± 0.25 pc. We conclude that systems equivalent to our solar system form in the Milky Way Galaxy at a rate of about 30 Myr−1, in which case approximately 36 000 solar-system analogs roam the Milky Way.
A novel high density W-30Cu alloy prepared via hydrothermal synthesis-co-reduction and canned hot extrusion methods
Authors: Li Jiwen , Ma Douqin , Xie Jingpei , Fang Fang , Xu Liujie , Wei Shizhong
Published: December 2018

We report herein the successful synthesis of in situ nanocomposite W-30Cu as powder via the hydrothermal approach combined with the co-reduction process, having sodium tungstate and copper nitrate as starting materials. The cold isostatic pressing, vacuum sintering and canned hot extrusion technology have been employed in order to improve the properties of the W-30Cu alloy. The impact of preparation’s methodologies on the microstructure, mechanical and physical properties have been investigated by the means of X-ray diffractometry (XRD); scanning electron (SEM); field emission electron (FE-SEM) and high-resolution electron (HRTEM) microscopies; conductivity meter and Brinell hardness tester. The results indicate that the precursor powder had a coating structure leading to W and Cu elements in situ symbiosis during the co-reduction period. The W-Cu reductive powder displayed an unstable core-shell structure of W coated Cu. During hot extrusion, the rapid mass transport, sintering mode conversion and bridge effect elimination enhance the density and properties of the W-Cu composites. The microstructure of the W-Cu composite exhibited a uniform distribution of W within the Cu phase with intact Cu network structure as well as fine W particles. The relative density, conductivity and hardness of the final product have reached 99.2%, 43.3% IACS and 214 HB, respectively, which are superior compared to those obtained by the traditional powder metallurgy methods.
Ingression orthodontique sur mini-vis d’ancrage
Authors: Ayadi Ines , Dallel Ines , Ben Rejeb Saloua , Tobji Samir , Ben Amor Faten , Ben Amor Adel
Published: December 2018

Introduction :L’ingression dentaire est depuis longtemps considérée comme l’un des mouvements les plus difficiles à réaliser en orthodontie. La principale difficulté rencontrée est, avec un traitement par mécaniques conventionnelles, la maîtrise d’ancrage, si délicate à assurer pour éviter des mouvements parasites presque certains. Les mini-vis émergent dans ce cadre comme un moyen d’ancrage très efficace, facilitant et simplifiant le mouvement d’ingression des dents, aussi bien antérieures que postérieures, sur le plan biomécanique, offrant à l’orthodontiste de nouvelles perspectives thérapeutiques.Objectif :L’objectif de notre travail est de décrire l’utilisation des mini-vis sur le plan clinique et biomécanique dans le cadre de l’ingression dentaire.
Corrélations entre les dimensions des végétations adénoïdes et les mensurations des arcades dentaires
Authors: Diouf Joseph Samba , Ouedraogo Youssouf , Seck Khady , Badiane Alpha , Ngom Papa Ibrahima , Diop-Ba Khady , Zouaki Ayoub , Diagne Falou
Published: December 2018

Introduction : L’hypertrophie des végétations adénoïdes est souvent associée à la ventilation buccale. Cette dernière peut impacter les mensurations des arcades dentaires. L’objectif de cette étude était de déterminer les relations entre les mensurations d’arcades et les dimensions des végétations adénoïdes. Matériels et méthodes : Une étude transversale a été réalisée sur 86 enfants. Les dimensions des végétations adénoïdes ont été déterminées à partir de neuf méthodes d’évaluations radiographiques et les mensurations des arcades réalisées sur les moulages. L’association entre le grade des végétations adénoïdes et les mensurations des arcades a été recherchée par une corrélation de Spearman. L’association entre les variables quantitatives d’évaluation des végétations adénoïdes et les mensurations d’arcades a été recherchée par une corrélation de Pearson. La puissance de ces associations a été analysée en utilisant les valeurs de Cohen en 1988. La signification est fixée à p = 0,05. Résultats : La profondeur d’arcade était significativement et positivement corrélée au grade des végétations selon la méthode de Holmberg et Linder-Aronson (rho = 0,55 ; p = 0,005) et aux mensurations des végétations selon les méthodes de Kemaloglu, Fujioka, Johannesson, De Menezes et Maran avec r respectivement égal à 0,65 ; 0,59 ; 0,63 ; 0,47 ; 0,74 et p respectivement égal à 0,001 ; 0,002 ; 0,001 ; 0,019 et < 0,001. Elle était aussi significativement mais négativement corrélée aux mensurations des végétations selon la méthode de Hibbert (r = – 0,52 ; p = 0,008). Le recouvrement était significativement et négativement corrélé aux mensurations des végétations selon la méthode de De Menezes (r = – 0,541 ; p = 0,006). Discussion : La puissance des associations montre que l’utilisation respective des méthodes de Maran et de De Menezes permet de mieux mettre en évidence l’association entre les dimensions des végétations adénoïdes et la profondeur d’arcade et le recouvrement.
Editorial
Authors: Lange Uwe
Published: December 2018

Liebe Kolleginnen und Kollegen,
die heutige Zeit ist gekennzeichnet durch schnellen Erkenntniszuwachs in fast allen medizinischen Fachdisziplinen mit konsekutiv fortschreitender Spezialisierung. Als positiv in diesem Prozess muss gewertet werden, dass Erkrankungen des rheumatischen Formenkreises zunehmende Bedeutung in der Medizin erlangen und rascher einer Diagnostik sowie adäquaten Therapie zugeführt werden. Kritisch einzustufen ist jedoch die Gefahr, dass der einzelne Facharzt mögliche „Brücken“ zwischen den verschiedenen Fachdisziplinen aus dem Auge verliert.
Aus Fehlern lernen
Authors: Fritzsche Madeleine , Schramm Christoph
Published: December 2018

Pflege oder Medizin ohne Fehler hat es nie gegeben und wird es wohl auch nie
geben. Fehler sind menschlich und nicht immer vermeidbar. Deshalb kommt es umso
mehr darauf an, sie frühzeitig zu erkennen und zu analysieren, um schädliche
Auswirkungen für die Patienten zu verhindern. Wie eine verlässliche
Sicherheitskultur im OP gelebt werden kann, lesen Sie in unserem
Schwerpunkt.
Willkommen an Bord
Authors: Gößwein David , Wetekam Ellen
Published: December 2018

Onboarding bezeichnet das „An-Bord-Nehmen“ neuer Mitarbeiter in die OP-Abteilung
und ist eine frühe und einflussreiche Möglichkeit, um Personal zu binden. Damit
die Integration erfolgreich verläuft, müssen jedoch viele Aspekte beachtet
werden. Unsere Autoren illustrieren die wichtigsten Erfolgsfaktoren für
Onboarding-Prozesse im OP und stellen ein Good-Practice-Projekt vor.
Auszeit für das Team
Authors: Weiler Michael
Published: December 2018

Trotz Zeitnot und Sparmaßnahmen steht die Sicherheit des Patienten immer an
erster Stelle. Deshalb wurde an der Kopfklinik des Universitätsklinikums
Heidelberg die Empfehlung der WHO-Sicherheitscheckliste implementiert und
erweitert. Unser Autor hat die Checklisten mitentwickelt und schildert Schritt
für Schritt, worauf es dabei insbesondere beim Team-Time-Out ankommt.
Design of New Amino Tf-Amide Organocatalysts: Environmentally Benign Approach to Asymmetric Aldol Synthesis
Authors: Lee Hyo-Jun , Arumugam Natarajan , Almansour Abdulrahman , Kumar Raju , Maruoka Keiji
Published: December 2018

A new type of optically pure primary amino aromatic Tf-amide organocatalyst can be easily prepared from 8-amino-1-tetralone, and its chemical behavior was investigated in the context of asymmetric aldol and Mannich reactions. Most notably, the asymmetric aldol reaction proceeded smoothly in brine.
Palladium-Catalyzed Carbonylation of Coumarin C(sp2)–H Bonds: A New Entry to Arylcoumarin Ketones
Authors: Pashazadeh Rahim , Mirzaei Siyavash , Rajai-Daryasarei Saideh , Soheilizad Mehdi , Kabiri Roya , Ansari Samira , Shabanian Meisam
Published: December 2018

A facile and efficient palladium-catalyzed carbonylation of coumarins involving two C–C bond formations has been developed. The C–H bond oxidative functionalization proceeds through aroylation with insertion of carbon monoxide to give arylcoumarin ketones. The reaction conditions, employing ambient pressures of CO gas as C1 feedstock, dramatically improve the generality of the carbonylation of aryl halides.
Exploration and Development of a C–H-Activated Route to Access the [1,2]Dithiolo[4,3-b]indole-3(4H)-thione Core and Related Derivatives
Authors: Asquith Christopher , Hilton Stephen , Konstantinova Lidia , Tizzard Graham , Laitinen Tuomo , Coles Simon , Rakitin Oleg
Published: December 2018

A robust procedure for the production of [1,2]dithiolo[4,3-b]indole-3(4H)-thione analogues using a DABCO/S2Cl2 complex as a sulfur source via a C–H activated approach.
Use of Tissue Expander for Contracted Scarred Saddle Deformity Rhinoplasty
Authors: Inman Jared , Ardeshirpour Farhad , Ostby Erin
Published: December 2018

The main purpose of this article is to present an alternative technique for the reconstruction of saddle nose deformity in patients with severely scarred or contracted soft tissue envelopes. In this single surgeon case series, the authors present a two-staged reconstruction performed on four adult patients with saddle nose deformities and contracted soft tissue envelope stemming from a variety of etiologic factors including vasculitis, sarcoidosis, and trauma. Stage one involved placement of a 1 × 4 cm tissue expander along the nasal dorsum through anterior scalp and endonasal incisions. The tissue expander port was positioned under the anterior scalp and injected with saline over 3 weeks in-office. Stage two involved removal of the tissue expander and rhinoplasty using osteocartilaginous rib grafts. All four patients had successful expansion of the contracted soft tissue envelope, creating adequate space for the newly reconstructed nasal framework. One patient developed exposure of the tissue expander through the endonasal incision, which did not lead to any adverse outcome. All patients in this series tolerated expansion well, without complaints of pain or external skin breakdown. The use of soft tissue expanders along the nasal dorsum can successfully expand contracted and scarred soft tissue envelopes prior to reconstructive rhinoplasty. This technique may be an effective alternative to the use of interpolated flaps in treating these patients.
Evaluation of Female Pelvic Pain
Authors: Chandler Jessica , Wagner Elena , Riley Kristin
Published: December 2018

Chronic pelvic pain is a condition defined by pelvic pain for more than six months which is severe enough to cause functional disability or require treatment. When pain becomes a chronic condition, it is more challenging to evaluate and treat. Chronic pelvic pain patients often have multiple factors contributing to their pain. Here, we review the approach to the evaluation of chronic female pelvic pain. It is important to establish a trusting patient–physician relationship. When evaluating a female patient with chronic pelvic pain, an in-depth history and targeted physical exam can localize contributors to pain. While limited, corresponding imaging and laboratory work should also be considered.