bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracting metal ions from water with redox active biopolymer electrodes
Authors: Admassie Shimelis , Elfwing Anders , Skallberg Andreas , Inganäs Olle
Published: February 2015

Lignin which is a renewable, environmentally friendly and cheap material is investigated as a promising material for use in energy storage and waste-water treatment technologies.
Temperature based adsorption studies of Cr(vi) using p-toluidine formaldehyde resin coated silica material
Authors: Dinker Manish Kumar , Kulkarni Prashant Shripad
Published: February 2015

A PTFR coated silica material was developed, characterised and applied for the treatment of hexavalent chromium.
The effect of surface passivation on the structure of sulphur-rich PbS colloidal quantum dots for photovoltaic application
Authors: Malgras Victor , Nattestad Andrew , Yamauchi Yusuke , Dou Shi Xue , Kim Jung Ho
Published: February 2015

In-depth structural study of methanol treated S-rich PbS quantum dots undergoing hydroxylation under atmospheric conditions.
X-ray crystallographic and kinetic investigations of 6-sulfamoyl-saccharin as a carbonic anhydrase inhibitor
Authors: Alterio V. , Tanc M. , Ivanova J. , Zalubovskis R. , Vozny I. , Monti S. M. , Di Fiore A. , De Simone G. , Supuran C. T.
Published: February 2015

Sulfamoylated saccharin binds to human carbonic anhydrase II through the SO2NH2and not CONHSO2moiety.
Visible-light-driven SnO2/TiO2 nanotube nanocomposite for textile effluent degradation
Authors: Rajkumar K. , Vairaselvi P. , Saravanan P. , Vinod V. T. P. , Černík Miroslav , Rajendra Kumar R. T.
Published: February 2015

A nanocomposite SnO2/TiO2 nanotube (NT) was prepared by following a simple two-step procedure, viz., hydrothermal preparation of TiO2 NT followed by chemical precipitation of SnO2 nanoparticle sensitized TiO2 NT.
A novel bifunctional molecularly imprinted polymer for determination of Congo red in food
Authors: Liu Fei , Zhang Shengchen , Wang Gailing , Zhao Jingchan , Guo Zhian
Published: February 2015

A novel bifunctional molecularly imprinted polymer was synthesized with beta-cyclodextrins-maleic anhydride and [2-(methacryloyloxy) ethyl] trimethylammonium chloride as co-functional monomers, and applied to the determination of food.
Extraction and determination of polycyclic aromatic hydrocarbons in water samples using stir bar sorptive extraction (SBSE) combined with dispersive liquid–liquid microextraction based on the solidification of floating organic drop (DLLME-SFO) followed by HPLC-UV
Authors: Shamsipur Mojtaba , Hashemi Beshare
Published: February 2015

The proposed method offers advantages, such as low consumption of organic solvents, high enrichment factors and good linearity, over the investigated concentration range.
Dihydropyrazoles containing morpholine: design, synthesis and bioassay testing as potent antimicrobial agents
Authors: Wang Peng-Fei , Qiu Han-Yue , Ma Jun-Ting , Yan Xiao-Qiang , Gong Hai-Bin , Wang Zhong-Chang , Zhu Hai-Liang
Published: February 2015

A series of dihydropyrazole derivatives were designed and synthesized as antimicrobial agents. In both docking simulation and bioassay tests, these compounds showed potent S. aureus TyrRS enzyme inhibition activity.
Blue fluorogenic probes for cell plasma membranes fill the gap in multicolour imaging
Authors: Kreder Rémy , Oncul Sule , Kucherak Oleksandr A. , Pyrshev Kyrylo A. , Real Eleonore , Mély Yves , Klymchenko Andrey S.
Published: February 2015

Newly synthesized blue membrane probes, due to high brightness, large Stokes shift and fluorogenic response, overcome the problem of cell auto-fluorescence and enable multicolor cellular imaging with common green and red markers.
Pd-catalyzed dehydrogenative C–H activation of iminyl hydrogen with the indole C3–H and C2–H bond: an elegant synthesis of indeno[1,2-b]indoles and indolo[1,2-a]indoles
Authors: Hazra Somjit , Mondal Biplab , De Rajendra Narayan , Roy Brindaban
Published: February 2015

This synthetic protocol describes two sequential C–H activation route towards indeno[1,2-b]indoles. Indolo[1,2-a]indoles were also synthesized by activating indole C2–H bond.
Screening donor groups of organic dyes for dye-sensitized solar cells
Authors: Yang Zhenqing , Shao Changjin , Cao Dapeng
Published: February 2015

Based on an experimentally synthesized dye D5 (also named d01 here), we designed and screened a series of dyes d02–d12 with different electron donors, and recommended several high performance dyes for DSSCs.
Re-evaluating the Cu K pre-edge XAS transition in complexes with covalent metal–ligand interactions
Authors: Tomson Neil C. , Williams Kamille D. , Dai Xuliang , Sproules Stephen , DeBeer Serena , Warren Timothy H. , Wieghardt Karl
Published: February 2015

Covalent metal–ligand interactions can lead to Cu K pre-edge transitions that result from metal-to-ligand charge transfer, instead of 1s → 3d, character.
Flexibility and protection by design: imbricated hybrid microstructures of bio-inspired armor
Authors: Rudykh Stephan , Ortiz Christine , Boyce Mary C.
Published: February 2015

Inspired by the imbricated scale-tissue flexible armor of elasmoid fish, we design hybrid stiff plate/soft matrix material architectures. Indentation and bending tests on bio-inspired 3D-printed prototype materials reveal their ability to provide protection against penetration while preserving flexibility.
Molecular weight characterization of single globular proteins using optical nanotweezers
Authors: Wheaton Skyler , Gordon Reuven
Published: February 2015

We trap a set of molecular weight standard globular proteins using a double nanohole optical trap.
An in situ growth approach to the fabrication of zeolite imidazolate framework-90 bonded capillary column for gas chromatography separation
Authors: Wu Ye-Yu , Yang Cheng-Xiong , Yan Xiu-Ping
Published: February 2015

Zeolite imidazolate framework-90 (ZIF-90) bonded capillary column was fabricated via an in situ growth approach. The prepared ZIF-90 bonded capillary column acts as a weak polar stationary phase and gave baseline separation of apolar and polar compounds.
Simultaneous and highly sensitive determination of PCBs and PBDEs in environmental water and sediments by gas chromatography coupled to high resolution magnetic sector mass spectrometry
Authors: Barco-Bonilla Nieves , Nieto-García Antonio José , Romero-González Roberto , Martínez Vidal José Luis , Frenich Antonia Garrido
Published: February 2015

Sensitive and simultaneous determination of PCBs and PBDEs in environmental samples (water and sediments) using high resolution magnetic sector mass spectrometry.
A biocompatible porous Mg-gallate metal–organic framework as an antioxidant carrier
Authors: Cooper Lucy , Hidalgo Tania , Gorman Martin , Lozano-Fernández Tamara , Simón-Vázquez Rosana , Olivier Camille , Guillou Nathalie , Serre Christian , Martineau Charlotte , Taulelle Francis , Damasceno-Borges Daiane , Maurin Guillaume , González-Fernández África , Horcajada Patricia , Devic Thomas
Published: February 2015

The slow release of gallic acid from a biocompatible porous MOF lead to a strong antioxidant activity.
Promiscuous hydroxylases for the functionalization of polycyclic tetramate macrolactams – conversion of ikarugamycin to butremycin
Authors: Greunke Christian , Antosch Janine , Gulder Tobias A. M.
Published: February 2015

Application of PTM hydroxylases facilitates the selective late-stage functionalization of complex PTM core structuresin vivoandin vitro.
A huge diamondoid metal–organic framework with a neo-mode of tenfold interpenetration
Authors: Tseng Tien-Wen , Luo Tzuoo-Tsair , Tsai Chen-Chuan , Lu Kuang-Lieh
Published: February 2015

A huge diamondoid framework with edge distances of the adamantane cages of up to 25.95 Å, is reported. This MOF displays a tenfold interpenetration, which is constructed from bulky and elongated aromatic-rigid dicarboxylate scaffolds, exhibits a self-catenated net with a point symbol of {(62.84)(64.8.10)2}.
p-Cyanophenylalanine and selenomethionine constitute a useful fluorophore–quencher pair for short distance measurements: application to polyproline peptides
Authors: Mintzer Mary Rose , Troxler Thomas , Gai Feng
Published: February 2015

The fluorescence of p-cyanophenylalanine is quenched by selenomethionine through an electron transfer process occurring at short distances.
Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems
Authors: Andrade Xavier , Strubbe David , De Giovannini Umberto , Larsen Ask Hjorth , Oliveira Micael J. T. , Alberdi-Rodriguez Joseba , Varas Alejandro , Theophilou Iris , Helbig Nicole , Verstraete Matthieu J. , Stella Lorenzo , Nogueira Fernando , Aspuru-Guzik Alán , Castro Alberto , Marques Miguel A. L. , Rubio Angel
Published: February 2015

We explore how strategies to simulate various phenomena of electronic systems have been implemented in the Octopus code, using the versatility and performance of real-space grids.
Nanoparticle assembly following Langmuir–Hinshelwood kinetics on a Langmuir film and chain networks captured in LB films
Authors: Maganti Lasya , Jash Madhuri , Nair Anju , Radhakrishnan T. P.
Published: February 2015

Negatively charged metal nanoparticles assemble as chain networks through Langmuir–Hinshelwood kinetics on a Langmuir film of positively charged amphiphiles. The extension of the networks captured in Langmuir–Blodgett films is tuned by the deposition pressure.
Towards superior volumetric performance: design and preparation of novel carbon materials for energy storage
Authors: Zhang Chen , Lv Wei , Tao Ying , Yang Quan-Hong
Published: February 2015

The design and fabrication of carbon materials are highlighted for high volumetric performance of EES devices.
Promoting catalysis and high-value product streams by in situ hydroxyapatite crystallization during hydrothermal liquefaction of microalgae cultivated with reclaimed nutrients
Authors: Roberts Griffin W. , Sturm Belinda S. M. , Hamdeh Umar , Stanton Gabriel E. , Rocha Alejandra , Kinsella Tiffany L. , Fortier Marie-Odile P. , Sazdar Shayan , Detamore Michael S. , Stagg-Williams Susan M.
Published: February 2015

A substituted, phase tunable hydroxyapatite is synthesized in situ during the hydrothermal liquefaction of algae.
Magnetophoresis ‘meets’ viscoelasticity: deterministic separation of magnetic particles in a modular microfluidic device
Authors: Del Giudice Francesco , Madadi Hojjat , Villone Massimiliano M. , D'Avino Gaetano , Cusano Angela M. , Vecchione Raffaele , Ventre Maurizio , Maffettone Pier Luca , Netti Paolo A.
Published: February 2015

Deflection of magnetic beads in a microfluidic channel can be improved through viscoelastic focusing.
First total synthesis of the marine natural products clavulolactones II and III
Authors: Miller Charlotte M. , Benneche Tore , Tius Marcus A.
Published: February 2015

The first total synthesis of the marine prostanoids clavulolactones II and III is presented from an easily accessible chiral, non-racemic cyclopentenone intermediate.
Functionalized triazolopeptoids – a novel class for mitochondrial targeted delivery
Authors: Althuon Daniela , Rönicke Franziska , Fürniss Daniel , Quan Jasmin , Wellhöfer Isabelle , Jung Nicole , Schepers Ute , Bräse Stefan
Published: February 2015

Here we introduce linear 1,4-triazolopeptoids as a novel class of cell penetrating peptidomimetics suitable as organ targeting molecular transporters of bioactive cargo.
Frequency control of crossover reactions in concurrent cationic vinyl-addition and ring-opening copolymerization of vinyl ethers and oxiranes: specific roles of weak Lewis bases and solvent polarity
Authors: Kanazawa Arihiro , Aoshima Sadahito
Published: February 2015

Weak Lewis bases and solvent polarity affected the frequency of the crossover reactions in the concurrent cationic vinyl-addition and ring-opening copolymerization of vinyl ethers and oxiranes.
l-Amino acid derived pyridinium-based chiral compounds and their efficacy in chiral recognition of lactate
Authors: Ghosh Kumaresh , Majumdar Anupam
Published: February 2015

A series ofl-amino acid derived pyridinium-based chiral compounds have been designed and synthesized. Among them, somel-valine derivatives show enantioselective recognition ofd-lactate in fluorescence.
Metal- and base-free syntheses of aryl/alkylthioindoles by the iodine-induced reductive coupling of aryl/alkyl sulfonyl chlorides with indoles
Authors: Kumaraswamy Gullapalli , Raju Ragam , Narayanarao Vykunthapu
Published: February 2015

Iodine-induced reductive coupling of aryl/alkyl sulfonyl chlorides with indoles leading to various substituted aryl/alkylthioindoles has been accomplished.
Application of classification models to identify solvents for single-walled carbon nanotubes dispersion
Authors: Salahinejad M.
Published: February 2015

In this study, a list of classification models was developed to categorise organic solvents with respect to their dispersibility of single-walled carbon nanotubes (SWNTs).
Plasma sprayed alumina–nanosilver antibacterial coatings
Authors: Gao Jinjin , Li Chunxia , Zhou Jingfang , Lu Liqiang , Zhao Chengjian , Zhu Yingchun
Published: February 2015

Plasma sprayed Al2O3/Ag hydrophobic coatings with no less than 10 ppm nanosilver exhibited strong anti-adhesive and antibacterial property.
Effects of peripheral substitutions on the singlet oxygen quantum yields of monophthalocyaninato ytterbium(iii) complexes
Authors: Zhang Quanquan , Cheng Guoe , Ke Hanzhong , Zhu Xunjin , Zhu Nianyong , Wong Wai-Yeung , Wong Wai-Kwok
Published: February 2015

A new monophthalocyaninato ytterbium(iii) complex5has been prepared and characterized. The effects of substituents on the relative singlet oxygen quantum yields of monophthalocyaninato ytterbium(iii) complexes have been investigated.
The development of artificial porphyrinoids embedded with functional building blocks
Authors: Zhou Zhikuan , Shen Zhen
Published: February 2015

The synthesis and applications of artificial porphyrinoids containing various functional building blocks by replacement of the pyrrole subunit have been summarized.
Achieving a large contrast, low driving voltage, and high stability electrochromic device with a viologen chromophore
Authors: Kao Sheng-Yuan , Kawahara Yuta , Nakatsuji Shin’ichi , Ho Kuo-Chuan
Published: February 2015

An electrochromic device that utilizes N,N,N′,N′-tetramethyl-p-phenylenediamine and the viologen radical salt (VRS) exhibits an extremely low driving voltage of 0.4 V, high transmittance change (>60% at 620 nm) and enhanced write–erase ability.
Iron alters cell survival in a mitochondria-dependent pathway in ovarian cancer cells
Authors: Bauckman Kyle , Haller Edward , Taran Nicholas , Rockfield Stephanie , Ruiz-Rivera Abigail , Nanjundan Meera
Published: February 2015

The role of iron in the development of cancer remains unclear. We previously reported that iron reduces cell survival in a Ras/mitogen-activated protein kinase (MAPK)-dependent manner in ovarian cells; however, the underlying downstream pathway leading to reduced survival was unclear. Although levels of intracellular iron, ferritin/CD71 protein and reactive oxygen species did not correlate with iron-induced cell survival changes, we identified mitochondrial damage (via TEM) and reduced expression of outer mitochondrial membrane proteins (translocase of outer membrane: TOM20 and TOM70) in cell lines sensitive to iron. Interestingly, Ru360 (an inhibitor of the mitochondrial calcium uniporter) reversed mitochondrial changes and restored cell survival in HEY ovarian carcinoma cells treated with iron. Further, cells treated with Ru360 and iron also had reduced autophagic punctae with increased lysosomal numbers, implying cross-talk between these compartments. Mitochondrial changes were dependent on activation of the Ras/MAPK pathway since treatment with a MAPK inhibitor restored expression of TOM20/TOM70 proteins. Although glutathione antioxidant levels were reduced in HEY treated with iron, extracellular glutamate levels were unaltered. Strikingly, oxalomalate (inhibitor of aconitase, involved in glutamate production) reversed iron-induced responses in a similar manner to Ru360. Collectively, our results implicate iron in modulating cell survival in a mitochondria-dependent manner in ovarian cancer cells.
Proline dehydrogenase 2 (PRODH2) is a hydroxyproline dehydrogenase (HYPDH) and molecular target for treating primary hyperoxaluria
Authors: Summitt Candice B. , Johnson Lynnette C. , Jönsson Thomas J. , Parsonage Derek , Holmes Ross P. , Lowther W. Todd
Published: February 2015

The primary hyperoxalurias (PH), types 1–3, are disorders of glyoxylate metabolism that result in increased oxalate production and calcium oxalate stone formation. The breakdown of trans-4-hydroxy-L-proline (Hyp) from endogenous and dietary sources of collagen makes a significant contribution to the cellular glyoxylate pool. Proline dehydrogenase 2 (PRODH2), historically known as hydroxyproline oxidase, is the first step in the hydroxyproline catabolic pathway and represents a drug target to reduce the glyoxylate and oxalate burden of PH patients. This study is the first report of the expression, purification, and biochemical characterization of human PRODH2. Evaluation of a panel of N-terminal and C-terminal truncation variants indicated that residues 157–515 contain the catalytic core with one FAD molecule. The 12-fold higher kcat/Km value of 0.93 M−1·s−1 for Hyp over Pro demonstrates the preference for Hyp as substrate. Moreover, an anaerobic titration determined a Kd value of 125 μM for Hyp, a value ~1600-fold lower than the Km value. A survey of ubiquinone analogues revealed that menadione, duroquinone, and CoQ1 reacted more efficiently than oxygen as the terminal electron acceptor during catalysis. Taken together, these data and the slow reactivity with sodium sulfite support that PRODH2 functions as a dehydrogenase and most likely utilizes CoQ10 as the terminal electron acceptor in vivo. Thus, we propose that the name of PRODH2 be changed to hydroxyproline dehydrogenase (HYPDH). Three Hyp analogues were also identified to inhibit the activity of HYPDH, representing the first steps toward the development of a novel approach to treat all forms of PH.
Regulation of IGFBP-2 expression during fasting
Authors: Kang Hye Suk , Kim Mi-Young , Kim Seung-Jae , Lee Jae-Ho , Kim Yong-Deuk , Seo Young-Kyo , Bae Jae-Hoon , Oh Goo-Taeg , Song Dae-Kyu , Ahn Yong-Ho , Im Seung-Soon
Published: February 2015

Insulin-like growth factor (IGF)-binding protein-2 (IGFBP-2) is known to attenuate the biological action of IGF-1, but its regulatory mechanism remains unclear. We demonstrate the transcriptional regulation of the hepatic Igfbp-2 gene by peroxisome-proliferator-activated receptor (PPAR) α during fasting. We also show how PPARα controls IGF-1 signalling through IGFBP-2.
Pancreatic β-cell identity, glucose sensing and the control of insulin secretion
Authors: Rutter Guy A. , Pullen Timothy J. , Hodson David J. , Martinez-Sanchez Aida
Published: February 2015

Insulin release from pancreatic β-cells is required to maintain normal glucose homoeostasis in man and many other animals. Defective insulin secretion underlies all forms of diabetes mellitus, a disease currently reaching epidemic proportions worldwide. Although the destruction of β-cells is responsible for Type 1 diabetes (T1D), both lowered β-cell mass and loss of secretory function are implicated in Type 2 diabetes (T2D). Emerging results suggest that a functional deficiency, involving de-differentiation of the mature β-cell towards a more progenitor-like state, may be an important driver for impaired secretion in T2D. Conversely, at least in rodents, reprogramming of islet non-β to β-cells appears to occur spontaneously in models of T1D, and may occur in man. In the present paper, we summarize the biochemical properties which define the ‘identity’ of the mature β-cell as a glucose sensor par excellence. In particular, we discuss the importance of suppressing a group of 11 ‘disallowed’ housekeeping genes, including Ldha and the monocarboxylate transporter Mct1 (Slc16a1), for normal nutrient sensing. We then survey the changes in the expression and/or activity of β-cell-enriched transcription factors, including FOXO1, PDX1, NKX6.1, MAFA and RFX6, as well as non-coding RNAs, which may contribute to β-cell de-differentiation and functional impairment in T2D. The relevance of these observations for the development of new approaches to treat T1D and T2D is considered.
Non-small-cell lung cancer and miRNAs: novel biomarkers and promising tools for treatment
Authors: Feng Bing , Zhang Kai , Wang Rui , Chen Longbang
Published: February 2015

Lung cancer is the leading cause of cancer-related death worldwide, with approximately 80–85% of cases being non-small-cell lung cancer (NSCLC). The miRNAs are small non-coding RNAs that regulate gene expression at a post-transcriptional level by either degradation or inhibition of the translation of target genes. Evidence is mounting that miRNAs exert pivotal effects in the development and progression of human malignancies, including NSCLC. A better understanding of the role that miRNAs play in the disease will contribute to the development of new diagnostic biomarkers and individualized therapeutic tools. In the present review, we briefly describe the role of miRNAs in NSCLC as well as the possible future of these discoveries in clinical applications.
Single‐input multiple‐output visible light optical wireless communications supporting quality of service
Authors: Chen Shih‐Hao , Chow Chi‐Wai
Published: February 2015

Visible light optical wireless communication supporting single‐input multiple‐output quality of service (QoS) by using an indoor light‐emitting diode, a mobile‐phone camera and a photodetector is proposed and demonstrated for the first time. The proposed system can support two fixed‐rate QoS transmissions for two different applications. By employing the rolling shutter effect of the mobile‐phone camera, the data rate of the first data link can be greatly enhanced. The experimental result shows that the proposed system can support the first data link operated at 300 bit/s by using a mobile‐phone camera and the second data link at 38.4 kbit/s by using a photodetector.
Reduced‐order model for MEMS PZT vibrational energy harvester exhibiting buckling bistability
Authors: Scerri J. , Grech I. , Gatt E. , Casha O.
Published: February 2015

Estimating the behaviour of buckling clamped–clamped beams entails solving nonlinear partial differential equations (PDEs). Several techniques are found in the literature that deal with such PDEs; techniques that also take into account initial curvatures and/or imperfections. However, when the system configuration is different from that of one single beam it becomes more involved. In this Letter, a buckling energy harvester is presented. Owing to the nature of its design, a nonlinear differential equation (not a PDE) capable of capturing all the salient characteristics of its behaviour could be developed. The effectiveness of the model is validated using finite element analysis. The energy harvester is designed using the SINTEF piezoVolume process and operated in the d31 mode. With electrical damping only, the device, designed for validation purposes, achieved a power density of 0.13 mW cm−3 at 3.5 g ms−2 at 560 Hz and produced d31 open‐circuit voltages of 0.6 V.
True random number generator resistant to frequency injection attacks
Authors: Wieczorek P.Z.
Published: February 2015

True random number generators (TRNGs) based on flip‐flop (FF) metastability can suffer from sensitivity to frequency injection attacks. A dedicated attack can interfere with a FF's initial condition and influence the logical state or resolve time. These, in turn might result in significant keyspace reduction. Therefore, a novel TRNG utilising random timing of metastable FF is proposed. In this concept, a programmable delay line driven by a pseudo‐random generator with a random seed, changes continuously the phase between triggering signals (data and clock) and the global system clock. Nevertheless, the relative interval of clock and data active slopes remains constant and violates FF timing to ensure metastable (truly random) operation.
Coherently integrated cubic phase function for multiple LFM signals analysis
Authors: Su Jia , Tao Hai‐hong , Rao Xuan , Xie Jian , Guo Xiao‐lu
Published: February 2015

The cubic phase function (CPF) based estimator is efficient in estimating the parameters for mono‐component linear frequency‐modulated (LFM) signals. However, it suffers from cross‐terms and spurious peaks when dealing with multi‐component LFM signals. Aimed at this identifiability problem, a coherently integrated CPF (CICPF) algorithm is proposed to enhance the auto‐terms and suppress spurious peaks. Comparisons with several existing algorithms are made, which show that the CICPF not only solve the identifiability problem for multi‐component LFM signals, but also acquires high anti‐noise performance.
Transmitter noise considerations in super‐Nyquist FMCW radar design
Authors: Ash M. , Brennan P.V.
Published: February 2015

A design consideration for super‐Nyquist frequency modulated continuous‐wave (FMCW) radar systems relating to transmitter to receiver noise leakage is introduced. Phase noise curves comparing the fundamental direct digital synthesisers frequency and its second super‐Nyquist image show a significant increase in relative noise level at all offsets from the carrier. This results in a reduced transmitter signal‐to‐noise ratio. It is shown with a simple example that this can lead to a significant degradation in receiver sensitivity if not managed properly. A design rule‐of‐thumb that can be used by radar designers to avoid or mitigate this problem is provided.
Mountainous terrain coverage in mobile sensor networks
Authors: Kim Kyungjun
Published: February 2015

The sensing field on three‐dimensional (3D) terrains that is supposed to be fully covered by deployed nodes may not be covered because of random aerial deployment. Non‐uniform coverage has a negative impact upon that their lifetime and performance get short and worse, respectively. Mobile sensor networks (MSNs) are introduced to improve a coverage problem from sensor malfunction by an obstacle or the terrestrial environment. Providing coverage in a mountainous terrain has become critical issues in MSNs. This work proposes a 3D coverage method that can consider a physical feature, such as slope, in a mountainous terrain, that is, a 3D spiral model that allows mobile sensors to move freely in spiral lines devised using the height and radius of a concaved terrain. In the proposed model, the reasonable number of sensors to be deployed and the designated sensing points achieve full coverage. This paper focuses on full coverage for which the spiral model challenges the reasonability in the number of sensors. The experimental results show that the proposed method provides improved performance in terms of coverage ratios and expected coverage time; in addition, this has higher accuracy in lower power cost and better expansibility.
Estimation of induction machine inductances using three‐dimensional magnetic equivalent circuit
Authors: Faiz Jawad , Ghasemi‐Bijan Mahmud
Published: February 2015

Estimation of inductances is one of the key points in a successful simulation of induction machines. These inductances are under the influences of different factors, such as winding distribution, stator and rotor slots, skewed slots of rotor, saturation of magnetic materials and asymmetries caused by eccentricities faults. This study introduces a method for a precise estimation of induction machine inductances based on three‐dimensional (3D) modelling using a magnetic equivalent circuit and considering the above‐mentioned factors. Furthermore, in 3D model, the axial flux ignored in the two‐dimensional model, is included. Enhancement of the accuracy of the tooth flux, precise modelling of the air gap and taking into account the skewed slots of rotor are the advantages of the 3D model. Also, the impact of different eccentricities fault upon the estimated inductances of the induction machine is addressed.
Modelling and verifying the load behaviour of electric vehicle charging stations based on field measurements
Authors: Leou Rong‐Ceng , Teng Jen‐Hao , Su Chun‐Lien
Published: February 2015

This study measures the long‐term electric energy data of an electric vehicle (EV) charging station, and uses these field measurements to analyse and construct the load behaviour model of an EV charging station. According to the statistics of field measurements, the state of charge of EV battery pack at the start of charging and the number of EVs starting charging in each time interval can be modelled using Poisson distribution, Roulette wheel selection and uniform distribution. The load behaviour of an EV charging station can be modelled and analysed accordingly. To validate the accuracy of the proposed load behaviour model, a portion of field measurements is reserved for load behaviour model verification. The proposed load behaviour model can also be used to analyse the impacts of EV charging stations on distribution systems. Test results show that the load behaviour model proposed in this study has higher accuracy and the impacts of EV charging stations on distribution systems can be analysed more effectively and precisely.
Wind generation as a reserve provider
Authors: Dvorkin Yury , Ortega‐Vazuqez Miguel A. , Kirschen Daniel S.
Published: February 2015

Wind generation is notorious for its high intermittency and limited predictability. To account for the uncertainty induced by wind in day‐ahead planning, system operators provide additional reserve by scheduling controllable generators at a less than optimal output, therefore increasing the operating cost and, in some cases, negating the benefits of relatively cheap wind generation. This study proposes a day‐ahead decision‐making framework that minimises the operating cost by derating the wind production and, consequently, reducing the reserve requirements. The headroom in wind generation that this deration creates is used to provide upward reserve. This deration also decreases the reserve requirement because it reduces the uncertainty of wind power generation. The proposed methodology has been tested on a modified 24‐bus IEEE Reliability Test System with different reserve policies under different wind penetration levels. This case study is based on the mixed‐integer linear unit commitment model, which enables exploring economic benefits of the proposed methodology while the technical constraints on the power system generation are duly enforced. The results demonstrate that the proposed methodology reduces the total operating cost, even when wind power producers are compensated for the reserve provision by their lost opportunity cost.
Enhancing the clustering process in the category model load profiling
Authors: Panapakidis Ioannis P. , Alexiadis Minas C. , Papagiannis Grigoris K.
Published: February 2015

Load profiling based consumer categorisation is a procedure that involves stages such as the proper representation of the load data, the selection of one or more pattern recognition algorithms, the assessment of their performance, the formation of daily load curve clusters for each consumer and the formation of the final consumer clusters. This study proposes improvements for every stage, while a new stage is introduced to enhance the whole procedure. All the pattern representation techniques of the load profiling related literature are examined together with the most widely used clustering algorithm, namely the K‐means. Two novel modified forms of the algorithm are introduced, specially designed by the authors for the problem under study. The aim is to optimally group together similar daily demand patterns to provide exploitable information to the utilities and the retailers for the efficient design and implementation of innovative energy services, targeted to the different consumer categories.
Deterministic methodologies for the quantification of voltage unbalance propagation in radial and interconnected networks
Authors: Jayatunga Upuli , Perera Sarath , Ciufo Phil , Agalgaonkar Ashish P.
Published: February 2015

Voltage unbalance propagation is an important aspect in relation to the voltage unbalance management process which aims to maintain acceptable voltage unbalance levels in the power system. The IEC Technical Report IEC/TR 61000‐3‐13:2008 incorporates the effects of voltage unbalance propagation in the voltage unbalance emission allocation methodology by introducing the voltage unbalance transfer coefficient, in order to evaluate the influence made by background voltage unbalance at the point of evaluation. However, no comprehensive approaches exist in the literature to evaluate these coefficients and the IEC work follows some approximations, which are deduced based on simulations and practical measurements. Recent work completed on voltage unbalance emission assessment at the post‐connection stage of unbalanced installations allows separation of the voltage unbalance emission contribution made by upstream/surrounding unbalance sources as a constituent component of the resultant voltage unbalance emission level at the point of evaluation. These new methodologies implicitly deal with the important aspects of voltage unbalance propagation and allow the quantification of coefficients associated with voltage unbalance propagation, which is the main thrust of this study. The theoretical work completed by considering different types of loads in radial and interconnected networks is supplemented by the simulation results.
Automated on‐line fault prognosis for wind turbine pitch systems using supervisory control and data acquisition
Authors: Chen Bindi , Matthews Peter C. , Tavner Peter J.
Published: February 2015

Current wind turbine (WT) studies focus on improving their reliability and reducing the cost of energy, particularly when WTs are operated offshore. A supervisory control and data acquisition (SCADA) system is a standard installation on larger WTs, monitoring all major WT sub‐assemblies and providing important information. Ideally, a WT's health condition or state of the components can be deduced through rigorous analysis of SCADA data. Several programmes have been made for that purposes; however, the resulting cost savings are limited because of the data complexity and relatively low number of failures that can be easily detected in early stages. This study proposes a new method for analysing WT SCADA data by using an a priori knowledge‐based adaptive neuro‐fuzzy inference system with the aim to achieve automated detection of significant pitch faults. The proposed approach has been applied to the pitch data of two different designs of 26 variable pitch, variable speed and 22 variable pitch, fixed speed WTs, with two different types of SCADA system, demonstrating the adaptability of the approach for application to a variety of techniques. Results are evaluated using confusion matrix analysis and a comparison study of the two tests is addressed to draw conclusions.
Increasing renewable penetration on islanded networks through active network management: a case study from Shetland
Authors: Gill Simon , Dolan Michael , Emhemed Abdullah , Kockar Ivana , Barnacle Malcolm , Ault Graham , Mathieson Colin
Published: February 2015

The drive to reduce reliance on fossil fuel generation in meeting power system demand is encouraging network operators to develop new methods managing network capacity while maintaining stability and security. Challenges relating to network stability are particularly acute on islanded networks. The Northern Isles New Energy Solutions (NINES) project is implementing techniques to manage the power network on the Shetland Islands in the UK. Active network management (ANM) is used to monitor and control generation in real time, and flexible demand is scheduled to minimise the use of conventional generation by reducing wind curtailment and minimising system losses. The flexible demand has the ability to respond to frequency and support system stability. This study presents the development of two modelling techniques used in the design and deployment of NINES – an ‘envelope of stability wind generation’ and the use of dynamic optimal power flow to schedule flexible demand. A case study is presented which shows that an ANM scheme managing flexible demand has the potential to increase wind capacity connected on Shetland from the existing 4 MW to 16.1 MW. Demand flexibility is shown to be capable of contributing up to 16.6 GWh towards reducing conventional generation.
Shielding effectiveness analysis of an infinite cylindrical structure with a lateral aperture by modal method of moments
Authors: Delafkar Hamideh , Dehkhoda Parisa , Tavakoli Ahad
Published: February 2015

In this study, an efficient and exact numerical technique based on modal method of moments (MoM) is presented to evaluate shielding effectiveness of an infinite cylindrical enclosure with a lateral aperture on its wall. To this end, modal vector wave functions are used to represent the electric field and consequently the surface magnetic current on the aperture. To calculate inside and outside magnetic fields, the circular waveguide dyadic Green's functions are utilised. The unknown magnetic current on the aperture is calculated using the MoM by enforcing the continuity of tangential magnetic field on the aperture. This method is employed for different enclosure sizes when illuminated by transverse magnetic (TM) polarised wave at two different incident angles.
Fully optimised charge simulation method by using particle swarm optimisation
Authors: Abd Elrahman Mohamed K.
Published: February 2015

Electric field intensity can be determined analytically, experimentally and numerically. Charge simulation method (CSM) is one of the most commonly used numerical methods for its many characteristics features. It can be used stand alone or in combination with other numerical methods. Sometimes optimisation techniques are used to facilitate the locating of the simulating charges as well as their values. Several optimisation techniques have emerged in the past decades that mimic biological evolution. The most representative techniques include genetic algorithms (GA) and particle swarm optimisation (PSO). Although PSO is more computationally efficient than GA, the later was used frequently to develop optimised versions of CSM during the last two decades. On the other hands, PSO technique was used recently only once to optimise the location of the simulating charges. In this study, the combination process between PSO and CSM became more convenient by optimising both charge locations and their values. This work eliminates the problems that were associated with the last trial and increases the degree of freedom that leads to solutions that are more realistic. The validity of the proposed method was verified by comparison with the analytical and numerical solutions.
Distortion measurement of exponential signal
Authors: Carnì Domenico Luca , Grimaldi Domenico , Lamonaca Francesco
Published: February 2015

Exponential voltage was proposed as a stimulus in the analog‐to‐digital converter (ADC) test because it is much more similar to the theoretical one than the sinusoidal signal. For the correct execution of the ADC test, the distortion of the exponential stimulus must be assessed by evaluating the amplitude and the time coefficient of the fundamental and the superimposed exponential components that best fit the real exponential voltage. To achieve this goal, the Prony‐like method is proposed in this paper. Two problems arise: the a priori evaluation of the degree of polynomial function that best fits the input samples, and the number of exponential components that have to be evaluated. To overcome these problems, two proper sub‐routines are pointed out allowing operation without a priori information and in accordance with the physical model of the signal. The results of experimental tests are shown in order to assess the correctness and the accuracy of the proposed procedure.
Application communication reliability of wireless sensor networks
Authors: Ehsani Zonouz Amir , Xing Liudong , Vokkarane Vinod M. , Sun Yan (Lindsay)
Published: February 2015

This paper considers application communication reliability (ACR) of wireless sensor networks (WSNs) supporting K ‐coverage in the presence of shadowing for a specific monitored area. Application communication relates to the acquisition of sensed data from a specific area and network connectivity that concerns the reliable delivery of the observed data from sensor nodes to the sink node. The analytical evaluation of ACR involves two steps: first identifying all the K ‐coverage sets, and then evaluating the communication reliability of delivering the observed data from sensor nodes within the identified K ‐coverage sets to the sink node. Two single‐path routing algorithms, shortest‐path distance algorithm and shortest‐path hop algorithm, are considered for evaluating the communication reliability during the second step. Their performances in terms of ACR and energy consumptions are compared through an empirical analysis of several examples. Results show that WSNs using the shortest‐path distance algorithm are more reliable than those using the shortest‐path hop algorithm in most cases, but consume more energy for delivering the sensed data to the sink node. Different scenarios are also considered to evaluate the impact of node density, channel condition and different monitored areas on ACR of WSNs.
Copper-Powder-Catalyzed Synthesis of Pyrimidines from β-Bromo α,β-Unsaturated Ketones and Amidine Hydrochlorides
Authors: Cho Chan , Jiao Yang , Ho Son
Published: February 2015

β-Bromo α,β-unsaturated ketones are coupled and cyclized with amidine hydrochlorides in the presence of a catalytic amount of copper powder along with a base to give the corresponding pyrimidines in good yields.
Penetrating Orbital-Cranial Injuries Management in a Limited Resource Hospital in Latin America
Authors: Estebanez Glyn , Garavito Diana , López Laura , Ortiz JuanCarlos , Rubiano Andrés M.
Published: February 2015

Penetrating orbital-cranial injuries (POCIs) are difficult cases especially in hospitals in low-middle-income countries (LMIC) where resources are limited. We present a case series of POCI managed in a university hospital in such scenario. A retrospective case series was conducted including patients with POCI in 2011. Mechanism of injury, Glasgow Coma Scale score, imaging, medical and surgical management, complications, and Glasgow Outcome Scale (GOS) score were analyzed. A total of 30 patients with penetrating orbital injuries were admitted from March 2011 to December 2011. Of this group, only four patients were diagnosed with cranial penetration. Computed tomography (CT) angiography revealed orbital fractures and injury to frontal, temporal, or occipital lobes. Urgent craniotomy with isolation of ipsilateral carotid artery was performed. GOS score at discharge was 5 in three patients and 4 in one patient. POCIs are not uncommon in hospitals of LMIC. In such scenarios, a standard approach with CT angiography and early neurosurgical intervention results in good outcome.
Spontaneous toroidal flow generation due to negative effective momentum diffusivity
Authors: McMillan Ben F.
Published: February 2015

Spontaneous structure formation, and in particular, zonal flows, is observed in a broad range of natural and engineered systems, often arising dynamically as the saturated state of a linear instability. Flows in tokamaks are known to self-organise on small scales, but large scale toroidal flows also arise even when externally applied torques are zero. This has previously been interpreted as the result of small externally imposed breaking of a symmetry. However, we show that for large enough field line pitch, a robust spontaneous symmetry breaking occurs, leading to the generation of strong toroidal flow structures; parameters are typical of Spherical Tokamak discharges with reversed shear profiles. The short wavelength dynamics are qualitatively similar to the growth of poloidal flow structures, and toroidal flow gradients nonlinearly saturate at levels where the shearing rate is comparable to linear growth rate. On long wavelengths, we measure Prandtl numbers of around zero for these systems, in conjunction with the formation of structured toroidal flows, and we show that this is consistent with a model of momentum transport where fluxes act to reinforce small flow gradients: the effective momentum diffusivity is negative. Toroidal flow structures are largely unaffected by collisional damping, so this may allow toroidal bulk flows of order the ion thermal velocity to be maintained with zero momentum input. This phenomenon also provides a mechanism for the generation of localised meso-scale structures like transport barriers.
Mapping the genome of meta-generalized gradient approximation density functionals: The search for B97M-V
Authors: Mardirossian Narbe , Head-Gordon Martin
Published: February 2015

A meta-generalized gradient approximation density functional paired with the VV10 nonlocal correlation functional is presented. The functional form is selected from more than 1010 choices carved out of a functional space of almost 1040 possibilities. Raw data come from training a vast number of candidate functional forms on a comprehensive training set of 1095 data points and testing the resulting fits on a comprehensive primary test set of 1153 data points. Functional forms are ranked based on their ability to reproduce the data in both the training and primary test sets with minimum empiricism, and filtered based on a set of physical constraints and an often-overlooked condition of satisfactory numerical precision with medium-sized integration grids. The resulting optimal functional form has 4 linear exchange parameters, 4 linear same-spin correlation parameters, and 4 linear opposite-spin correlation parameters, for a total of 12 fitted parameters. The final density functional, B97M-V, is further assessed on a secondary test set of 212 data points, applied to several large systems including the coronene dimer and water clusters, tested for the accurate prediction of intramolecular and intermolecular geometries, verified to have a readily attainable basis set limit, and checked for grid sensitivity. Compared to existing density functionals, B97M-V is remarkably accurate for non-bonded interactions and very satisfactory for thermochemical quantities such as atomization energies, but inherits the demonstrable limitations of existing local density functionals for barrier heights.
Observation of the wavepacket dynamics on the 1B2(1Σu+) state of CS2 by sub-20 fs photoelectron imaging using 159 nm probe pulses
Authors: Spesyvtsev R. , Horio T. , Suzuki Y.-I. , Suzuki T.
Published: February 2015

The wavepacket dynamics of CS2 after photoexcitation to the 1B2(1Σu+) state at 198 nm are studied by time-resolved photoelectron imaging using sub-20 fs 159 nm pulses, which enable single photon ionization from the entire region of the 1B2 potential energy surface. The time-energy map of the photoelectron intensity reveals vibrational motions along the symmetric stretching and bending coordinates. The time-energy map of the photoelectron anisotropy parameter exhibits time-evolution within single oscillation periods of the ν1 and ν2 modes, which is attributed to variation of the excited state electronic character along these vibrational coordinates. The initially populated 1B2 state evolves with two time constants of 107 and 394 fs.