bluuebunny/crossref_metadata_2025 huggingface dataset:
Plasma Leakage from the Centrifugal Magnetospheres of Magnetic B-Type Stars
Authors: Shultz Matt , Wade Gregg , Rivinius Thomas , Grunhut Jason , Petit Véronique ,   the MiMeS Collaboration
Published: January 2015

Magnetic B-type stars are often host to Centrifugal Magnetospheres (CMs). Here we describe the results of a population study encompassing the full sample of known magnetic early B-type stars, focusing on those with detectable CMs. We present revised rotational and magnetic parameters for some stars, clarifying their positions on the rotation-confinement diagram, and find that plasma densities within their CMs is much lower than those predicted by centrifugal breakout.
Accretion Signatures on Massive Young Stellar Objects
Authors: Navarete F. , Damineli A. , Barbosa C. L. , Blum R. D.
Published: January 2015

We present preliminary results from a survey of molecular H2 (2.12 μm) emission in massive young stellar objects (MYSO) candidates selected from the Red MSX Source survey. We observed 354 MYSO candidates through the H2 S(1) 1-0 transition (2.12 μm) and an adjacent continuum narrow-band filters using the Spartan/SOAR and WIRCam/CFHT cameras. The continuum-subtracted H2 maps were analyzed and extended H2 emission was found in 50% of the sample (178 sources), and 38% of them (66) have polar morphology, suggesting collimated outflows. The polar-like structures are more likely to be driven on radio-quiet sources, indicating that these structures occur during the pre-ultra compact H ii phase. We analyzed the continuum images and found that 54% (191) of the sample displayed extended continuum emission and only ~23% (80) were associated to stellar clusters. The extended continuum emission is correlated to the H2 emission and those sources within stellar clusters does display diffuse H2 emission, which may be due to fluorescent H2 emission. These results support the accretion scenario for massive star formation, since the merging of low-mass stars would not produce jet-like structures. Also, the correlation between jet-like structures and radio-quiet sources indicates that higher inflow rates are required to form massive stars in a typical timescale less than 105 years.
Asteroseismology of Massive Stars: Some Words of Caution
Authors: Noels A. , Godart M. , Salmon S. J. A. J. , Gabriel M. , Montalbán J. , Miglio A.
Published: January 2015

Although playing a key role in the understanding of the supernova phenomenon, the evolution of massive stars still suffers from uncertainties in their structure, even during their “quiet” main sequence phase and later on during their subgiant and helium burning phases. What is the extent of the mixed central region? In the local mixing length theory (LMLT) frame, are there structural differences using Schwarzschild or Ledoux convection criterion? Where are located the convective zone boundaries? Are there intermediate convection zones during MS and post-MS phase, and what is their extent and location? We discuss these points and show how asteroseismology could bring some light on these questions.
Is Islam a Cure for Ethnic Conflict? Evidence from Turkey
Authors: Gurses Mehmet
Published: January 2015

Turkish Islamists have long attributed the root causes of the Kurdish conflict in Turkey to the anti-religious Turkish nationalism promulgated by the secular Kemalist republican elite in the 1920s. As a result, they lay emphasis on “Islamic brotherhood” as the glue that holds numerous ethnic nationalities together. This article examines this claim and argues that Islam's role as a peacemaker has been overstated. The data from in-depth interviews with dozens of Kurdish Islamists in Turkey conducted in the summer of 2013 indicate that Kurdish Islamists in principle agree with the peacemaking potential of Islam. Distrustful of the “Islamic brotherhood” discourse however, they describe this allegedly new policy as yet another tactic to undermine the Kurdish struggle for equal rights
Does rat fetal DNA induce preeclampsia in pregnant rats?
Authors: Konečná B. , Borbélyová V. , Celec P. , Vlková B.
Published: January 2015

Cell-free fetal DNA in maternal circulation is higher during preeclampsia. It is unclear whether it is the cause or the consequence of the disease. The aim of this study was to prove whether injected rat fetal DNA induces preeclampsia-like symptoms in pregnant Wistar rats. They received daily i.p. injections of water or rat fetal DNA (400 μg) from gestation day 14 to 18. Blood pressure, proteinuria, placental and fetal weight were measured at gestation day 19. Plasma DNase activity, proteinuria and creatinine clearance were assessed. There was no significant difference in any of the measured parameters. The results of this study do not confirm the hypothesis that fetal DNA might induce preeclampsia. This is in contrast to others using human fetal DNA in mice. Further studies should be focused on the effects of fetal DNA from the same species protected from DNase activity.
Genomic assays for Epstein–Barr virus-positive gastric adenocarcinoma
Authors: Gulley Margaret L
Published: January 2015

A small set of gastric adenocarcinomas (9%) harbor Epstein–Barr virus (EBV) DNA within malignant cells, and the virus is not an innocent bystander but rather is intimately linked to pathogenesis and tumor maintenance. Evidence comes from unique genomic features of host DNA, mRNA, microRNA and CpG methylation profiles as revealed by recent comprehensive genomic analysis by The Cancer Genome Atlas Network. Their data show that gastric cancer is not one disease but rather comprises four major classes: EBV-positive, microsatellite instability (MSI), genomically stable and chromosome instability. The EBV-positive class has even more marked CpG methylation than does the MSI class, and viral cancers have a unique pattern of methylation linked to the downregulation of CDKN2A (p16) but not MLH1. EBV-positive cancers often have mutated PIK3CA and ARID1A and an amplified 9p24.1 locus linked to overexpression of JAK2, CD274 (PD-L1) and PDCD1LG2 (PD-L2). Multiple noncoding viral RNAs are highly expressed. Patients who fail standard therapy may qualify for enrollment in clinical trials targeting cancer-related human gene pathways or promoting destruction of infected cells through lytic induction of EBV genes. Genomic tests such as the GastroGenus Gastric Cancer Classifier are available to identify actionable variants in formalin-fixed cancer tissue of affected patients.
Microbial dark matter ecogenomics reveals complex synergistic networks in a methanogenic bioreactor
Authors: Nobu Masaru K , Narihiro Takashi , Rinke Christian , Kamagata Yoichi , Tringe Susannah G , Woyke Tanja , Liu Wen-Tso
Published: January 2015

Ecogenomic investigation of a methanogenic bioreactor degrading terephthalate (TA) allowed elucidation of complex synergistic networks of uncultivated microorganisms, including those from candidate phyla with no cultivated representatives. Our previous metagenomic investigation proposed that Pelotomaculum and methanogens may interact with uncultivated organisms to degrade TA; however, many members of the community remained unaddressed because of past technological limitations. In further pursuit, this study employed state-of-the-art omics tools to generate draft genomes and transcriptomes for uncultivated organisms spanning 15 phyla and reports the first genomic insight into candidate phyla Atribacteria, Hydrogenedentes and Marinimicrobia in methanogenic environments. Metabolic reconstruction revealed that these organisms perform fermentative, syntrophic and acetogenic catabolism facilitated by energy conservation revolving around H2 metabolism. Several of these organisms could degrade TA catabolism by-products (acetate, butyrate and H2) and syntrophically support Pelotomaculum. Other taxa could scavenge anabolic products (protein and lipids) presumably derived from detrital biomass produced by the TA-degrading community. The protein scavengers expressed complementary metabolic pathways indicating syntrophic and fermentative step-wise protein degradation through amino acids, branched-chain fatty acids and propionate. Thus, the uncultivated organisms may interact to form an intricate syntrophy-supported food web with Pelotomaculum and methanogens to metabolize catabolic by-products and detritus, whereby facilitating holistic TA mineralization to CO2 and CH4.
Ecophysiology of uncultivated marine euryarchaea is linked to particulate organic matter
Authors: Orsi William D , Smith Jason M , Wilcox Heather M , Swalwell Jarred E , Carini Paul , Worden Alexandra Z , Santoro Alyson E
Published: January 2015

Particles in aquatic environments host distinct communities of microbes, yet the evolution of particle-specialized taxa and the extent to which specialized microbial metabolism is associated with particles is largely unexplored. Here, we investigate the hypothesis that a widely distributed and uncultivated microbial group—the marine group II euryarchaea (MGII)—interacts with living and detrital particulate organic matter (POM) in the euphotic zone of the central California Current System. Using fluorescent in situ hybridization, we verified the association of euryarchaea with POM. We further quantified the abundance and distribution of MGII 16 S ribosomal RNA genes in size-fractionated seawater samples and compared MGII functional capacity in metagenomes from the same fractions. The abundance of MGII in free-living and >3 μm fractions decreased with increasing distance from the coast, whereas MGII abundance in the 0.8–3 μm fraction remained constant. At several offshore sites, MGII abundance was highest in particle fractions, indicating that particle-attached MGII can outnumber free-living MGII under oligotrophic conditions. Compared with free-living MGII, the genome content of MGII in particle-associated fractions exhibits an increased capacity for surface adhesion, transcriptional regulation and catabolism of high molecular weight substrates. Moreover, MGII populations in POM fractions are phylogenetically distinct from and more diverse than free-living MGII. Eukaryotic phytoplankton additions stimulated MGII growth in bottle incubations, providing the first MGII net growth rate measurements. These ranged from 0.47 to 0.54 d−1. However, MGII were not recovered in whole-genome amplifications of flow-sorted picoeukaryotic phytoplankton and heterotrophic nanoflagellates, suggesting that MGII in particle fractions are not physically attached to living POM. Collectively, our results support a linkage between MGII ecophysiology and POM, implying that marine archaea have a role in elemental cycling through interactions with particles.
Evidence for a small hole pocket in the Fermi surface of underdoped YBa2Cu3Oy
Authors: Doiron-Leyraud N. , Badoux S. , René de Cotret S. , Lepault S. , LeBoeuf D. , Laliberté F. , Hassinger E. , Ramshaw B. J. , Bonn D. A. , Hardy W. N. , Liang R. , Park J.-H.. , Vignolles D. , Vignolle B. , Taillefer L. , Proust C.
Published: January 2015

In underdoped cuprate superconductors, the Fermi surface undergoes a reconstruction that produces a small electron pocket, but whether there is another, as yet, undetected portion to the Fermi surface is unknown. Establishing the complete topology of the Fermi surface is key to identifying the mechanism responsible for its reconstruction. Here we report evidence for a second Fermi pocket in underdoped YBa2Cu3Oy, detected as a small quantum oscillation frequency in the thermoelectric response and in the c-axis resistance. The field-angle dependence of the frequency shows that it is a distinct Fermi surface, and the normal-state thermopower requires it to be a hole pocket. A Fermi surface consisting of one electron pocket and two hole pockets with the measured areas and masses is consistent with a Fermi-surface reconstruction by the charge–density–wave order observed in YBa2Cu3Oy, provided other parts of the reconstructed Fermi surface are removed by a separate mechanism, possibly the pseudogap.
Site- and allele-specific polycomb dysregulation in T-cell leukaemia
Authors: Navarro Jean-Marc , Touzart Aurore , Pradel Lydie C. , Loosveld Marie , Koubi Myriam , Fenouil Romain , Le Noir Sandrine , Maqbool Muhammad Ahmad , Morgado Ester , Gregoire Claude , Jaeger Sebastien , Mamessier Emilie , Pignon Charles , Hacein-Bey-Abina Salima , Malissen Bernard , Gut Marta , Gut Ivo G. , Dombret Hervé , Macintyre Elizabeth A. , Howe Steven J. , Gaspar H. Bobby , Thrasher Adrian J. , Ifrah Norbert , Payet-Bornet Dominique , Duprez Estelle , Andrau Jean-Christophe , Asnafi Vahid , Nadel Bertrand
Published: January 2015

T-cell acute lymphoblastic leukaemias (T-ALL) are aggressive malignant proliferations characterized by high relapse rates and great genetic heterogeneity. TAL1 is amongst the most frequently deregulated oncogenes. Yet, over half of the TAL1+ cases lack TAL1 lesions, suggesting unrecognized (epi)genetic deregulation mechanisms. Here we show that TAL1 is normally silenced in the T-cell lineage, and that the polycomb H3K27me3-repressive mark is focally diminished in TAL1+ T-ALLs. Sequencing reveals that >20% of monoallelic TAL1+ patients without previously known alterations display microinsertions or RAG1/2-mediated episomal reintegration in a single site 5′ to TAL1. Using ‘allelic-ChIP’ and CrispR assays, we demonstrate that such insertions induce a selective switch from H3K27me3 to H3K27ac at the inserted but not the germline allele. We also show that, despite a considerable mechanistic diversity, the mode of oncogenic TAL1 activation, rather than expression levels, impact on clinical outcome. Altogether, these studies establish site-specific epigenetic desilencing as a mechanism of oncogenic activation.
Suppression of Mic60 compromises mitochondrial transcription and oxidative phosphorylation
Authors: Yang Rui-Feng , Sun Li-Hong , Zhang Ran , Zhang Yuan , Luo Yu-Xuan , Zheng Wei , Zhang Zhu-Qin , Chen Hou-Zao , Liu De-Pei
Published: January 2015

Precise regulation of mtDNA transcription and oxidative phosphorylation (OXPHOS) is crucial for human health. As a component of mitochondrial contact site and cristae organizing system (MICOS), Mic60 plays a central role in mitochondrial morphology. However, it remains unclear whether Mic60 affects mitochondrial transcription. Here, we report that Mic60 interacts with mitochondrial transcription factors TFAM and TFB2M. Furthermore, we found that Mic60 knockdown compromises mitochondrial transcription and OXPHOS activities. Importantly, Mic60 deficiency decreased TFAM binding and mitochondrial RNA polymerase (POLRMT) recruitment to the mtDNA promoters. In addition, through mtDNA immunoprecipitation (mIP)-chromatin conformation capture (3C) assays, we found that Mic60 interacted with mtDNA and was involved in the architecture of mtDNA D-loop region. Taken together, our findings reveal a previously unrecognized important role of Mic60 in mtDNA transcription.
Rapid identification of edible oil and swill-cooked dirty oil by using near-infrared spectroscopy and sparse representation classification
Authors: Zhou Yang , Liu Tiebing , Li Jinrong , Chen Zhengwei
Published: January 2015

Rapid identification of edible oil and swill-cooked dirty oil is a challenging and important task in the field of food safety.
Emergence of tunable resistive pulse sensing as a biosensor
Authors: Blundell Emma L. C. J. , Mayne Laura J. , Billinge Emily R. , Platt Mark
Published: January 2015

A review and tutorial on tunable resistive pulse sensors used as biosensors.
Ultrasensitive, highly specific, colorimetric recognition of sulfide ions [S2−] in aqueous media: applications to environmental analysis
Authors: Kondekar Uttam R. , Walekar Laxman S. , Gore Anil H. , Anbhule Prashant V. , Han Sung H. , Patil Shivajirao R. , Kolekar Govind B.
Published: January 2015

Herein, we have demonstrated the simple, ultrasensitive and highly specific colorimetric assay for the detection of sulfide ions (S2−) based on interaction of the surface capped gold nanoparticles with S2− in aqueous media.
Liquid–liquid interface-mediated room-temperature synthesis of amorphous NiCo pompoms from ultrathin nanosheets with high catalytic activity for hydrazine oxidation
Authors: Wang Hui , Ma Yanjiao , Wang Rongfang , Key Julian , Linkov Vladimir , Ji Shan
Published: January 2015

NixCoyalloy pompoms formed by the aggregation of nano ultrathin sheets were prepared by simultaneous reduction of NiCl2and CoCl2with NaBH4viaa liquid–liquid interface reaction.
Exploring excited states of Pt(ii) diimine catecholates for photoinduced charge separation
Authors: Scattergood Paul A. , Jesus Patricia , Adams Harry , Delor Milan , Sazanovich Igor V. , Burrows Hugh D. , Serpa Carlos , Weinstein Julia A.
Published: January 2015

Photoacoustic calorimetry investigates electron injection into semiconductors from Pt(ii) diimine catecholates incorporated into DSSCs.
Design, optical and antimicrobial properties of extremely thin alumina films colored with silver nanospecies
Authors: Jagminas A. , Žalnėravičius R. , Rėza A. , Paškevičius A. , Selskienė A.
Published: January 2015

Extremely thin alumina films gold-colored by silver nm-scaled species possess a low refractive index and antimicrobial efficiency.
Promoted C–C bond cleavage over intermetallic TaPt3 catalyst toward low-temperature energy extraction from ethanol
Authors: Kodiyath Rajesh , Ramesh Gubbala V. , Koudelkova Eva , Tanabe Toyokazu , Ito Mikio , Manikandan Maidhily , Ueda Shigenori , Fujita Takeshi , Umezawa Naoto , Noguchi Hidenori , Ariga Katsuhiko , Abe Hideki
Published: January 2015

Intermetallic TaPt3 nanoparticles promote C–C bond cleavage in ethanol and exhibit much higher catalytic performance than traditional catalysts for the ethanol electrooxidation.
Copper tolerance and virulence in bacteria
Authors: Ladomersky Erik , Petris Michael J.
Published: January 2015

Copper (Cu) is an essential trace element for all aerobic organisms.
Comment on “The role of electrostatic induction in secondary isotope effects on acidity” by E. A. Halevi, New J. Chem., 2014, 38, 3840
Authors: Perrin Charles L.
Published: January 2015

We reject Halevi's interpretation and reaffirm our conclusion that secondary deuterium isotope effects on acidity are due to n–σ* delocalization.
Solvent-free carbonylation of glycerol with urea using metal loaded MCM-41 catalysts
Authors: Kondawar S. E. , Potdar A. S. , Rode C. V.
Published: January 2015

Reacting glycerol with urea is the most attractive option for the production of glycerol carbonate (GC), as it utilizes two inexpensive chemicals readily available in the chemical cycle.
Thermal responsive fluorescent nanocomposites based on carbon dots
Authors: Zhao Xiaohuan , Zhu Shoujun , Song Yubin , Zhang Junhu , Yang Bai
Published: January 2015

PNIPAM & CDs composites have been used as a sensor of temperature. At around 32 °C, the fluorescent intensity decrease sharply because of CDs' self-quenching effect.
The hypersaline synthesis of titania: from powders to aerogels
Authors: Nisticò R. , Magnacca G.
Published: January 2015

This paper deals with the titania powders and aerogels production using inorganic water-soluble salts as porogens (salt-templating via hypersaline medium).
Development of hypoxia-triggered prodrug micelles as doxorubicin carriers for tumor therapy
Authors: Liu Hongmei , Zhang Ruilong , Niu Yunwei , Li Yan , Qiao Chenmeng , Weng Jie , Li Jun , Zhang Xiaoning , Xiao Zuobing , Zhang Xin
Published: January 2015

Hypoxia-responsive prodrug micelles to deliver anticancer drug, which can selectively release the drugs to treat hypoxic tumor cells.
Nickel oxide nanopetal-decorated 3D nickel network with enhanced pseudocapacitive properties
Authors: Cheng Guanhua , Bai Qingguo , Si Conghui , Yang Wanfeng , Dong Chaoqun , Wang Hao , Gao Yulai , Zhang Zhonghua
Published: January 2015

Calcination of anodized nickel foam has been used to synthesize NiO nanopetals electrodes with enhanced electrochemical performance.
Simultaneous extraction of bisphenol A and tetrabromobisphenol A from milk by microwave-assisted ionic liquid microextraction
Authors: Kang Haiyan , Wang Xianli , Zhang Yan , Wu Junfeng , Wang Hongqiang
Published: January 2015

A rapid, simple and efficient method was first applied to the simultaneous analysis of BPA and TBBPA in commercial milk.
Multiwall carbon nanotube-modified electrode as a nanosensor for electrochemical studies and stripping voltammetric determination of an antimalarial drug
Authors: Ghoreishi Sayed Mehdi , Attaran Abdol Mohammad , Amin Atiyeh Moqadam , Khoobi Asma
Published: January 2015

MWCNTs/CPE exhibited excellent effect towards the oxidation of hydroxychloroquine.
Ni(ii) source as a pre-catalyst for the cross-coupling of benzylic pivalates with arylboronic acids: facile access to tri- and diarylmethanes
Authors: Chen Qiang , Fan Xin-Heng , Zhang Li-Peng , Yang Lian-Ming
Published: January 2015

Various di- and triarylmethanes were synthesized via NiII–(σ-aryl) complex-catalyzed Suzuki–Miyaura cross-coupling of benzylic pivalates with arylboronic acids under mild conditions.
Dynamical effects on the magnetic properties of dithiazolyl bistable materials
Authors: Vela Sergi , Deumal Mercè , Shiga Motoyuki , Novoa Juan J. , Ribas-Arino Jordi
Published: January 2015

Using 1,3,5-trithia-2,4,6-triazapentalenyl material as a proof of concept, we demonstrate that vibrations of radicals can play a prime role in defining the magnetic properties of certain organic magnets.
Visualizing order in dispersions and solid state morphology with Cryo-TEM and electron tomography: P3HT : PCBM organic solar cells
Authors: Wirix Maarten J. M. , Bomans Paul H. H. , Hendrix Marco M. R. M. , Friedrich Heiner , Sommerdijk Nico A. J. M. , de With Gijsbertus
Published: January 2015

Building blocks for organic solar cells are made from P3HT in a P3HT : PCBM solution in toluene and used to tune the morphology of the photoactive layer.
Composition-dependent activity of Cu–Pt alloy nanocubes for electrocatalytic CO2 reduction
Authors: Zhao Xueyu , Luo Binbin , Long Ran , Wang Chengming , Xiong Yujie
Published: January 2015

A protocol has been developed for the synthesis of Cu–Pt alloy nanocubes with a relatively broad range of composition ratios, enabling the investigation of their composition-dependent activity for electrocatalytic CO2 reduction.
Encapsulation of VEGF165into magnetic PLGA nanocapsules for potential local delivery and bioactivity in human brain endothelial cells
Authors: Carenza E. , Jordan O. , Martínez-San Segundo P. , Jiřík R. , Starčuk jr Z. , Borchard G. , Rosell A. , Roig A.
Published: January 2015

New drug delivery systems based on biodegradable magnetic nanocapsules for targeted delivery of pro-angiogenic proteins, potentially useful in therapeutic angiogenesis, are reported.
Cerium dioxide nanoparticles protect against oxidative stress induced injury through modulation of TGF-β signalling
Authors: Guo Chang , Smith Rachel , Gant Timothy W. , Leonard Martin O.
Published: January 2015

Cerium oxide nanoparticles attenuate oxidative stress induced alterations in TGF-β signalling pathway members.
Preparation of nanodiamonds from carbon nanoparticles at atmospheric pressure
Authors: Kamali Ali Reza , Fray Derek J.
Published: January 2015

A route for producing diamond nanocrystals is reported in this paper.
Reversible C–C coupling in phenanthroline complexes of divalent samarium and thulium
Authors: Nocton Grégory , Ricard Louis
Published: January 2015

The phenanthroline adducts of organosamarium and organothulium fragments feature a reversible C–C bond on the phenanthroline ligand.
Correction: Utilizing the bioorthogonal base-pairing system of l-DNA to design ideal DNA nanocarriers for enhanced delivery of nucleic acid cargos
Authors: Kim Kyoung-Ran , Lee Taemin , Kim Byeong-Su , Ahn Dae-Ro
Published: January 2015

Correction for ‘Utilizing the bioorthogonal base-pairing system of l-DNA to design ideal DNA nanocarriers for enhanced delivery of nucleic acid cargos’ by Kyoung-Ran Kim et al., Chem. Sci., 2014, 5, 1533–1537.
Evaluating Language Environment Analysis System Performance for Chinese: A Pilot Study in Shanghai
Authors: Gilkerson Jill , Zhang Yiwen , Xu Dongxin , Richards Jeffrey A. , Xu Xiaojuan , Jiang Fan , Harnsberger James , Topping Keith
Published: January 2015

Purpose

The purpose of this study was to evaluate performance of the Language Environment Analysis (LENA) automated language-analysis system for the Chinese Shanghai dialect and Mandarin (SDM) languages.

Method

Volunteer parents of 22 children aged 3–23 months were recruited in Shanghai. Families provided daylong in-home audio recordings using LENA. A native speaker listened to 15 min of randomly selected audio samples per family to label speaker regions and provide Chinese character and SDM word counts for adult speakers. LENA segment labeling and counts were compared with rater-based values.

Results

LENA demonstrated good sensitivity in identifying adult and child; this sensitivity was comparable to that of American English validation samples. Precision was strong for adults but less so for children. LENA adult word count correlated strongly with both Chinese characters and SDM word counts. LENA conversational turn counts correlated similarly with rater-based counts after the exclusion of three unusual samples. Performance related to some degree to child age.

Conclusions

LENA adult word count and conversational turn provided reasonably accurate estimates for SDM over the age range tested. Theoretical and practical considerations regarding LENA performance in non-English languages are discussed. Despite the pilot nature and other limitations of the study, results are promising for broader cross-linguistic applications.
High‐resolution inverse synthetic aperture radar imaging of manoeuvring targets with sparse aperture
Authors: Xu Gang , Xing Mengdao , Bao Zheng
Published: January 2015

In high‐resolution radar imaging, there is inevitable migration through range cells (MTRCs) in an inverse synthetic aperture radar (ISAR) image due to the manoeuvrability of the target. In the case of sparse aperture (SA) measurement, it is generally difficult to accurately correct MTRCs to degrade the imaging performance. An approach of SA‐imaging jointly with MTRC correction for manoeuvring targets is presented. Under a chirp‐Fourier dictionary by involving MTRCs, the ISAR image formation is treated as a sparse‐driven optimisation to overcome the SA. Experiments based on the measured data are performed to confirm the effectiveness of the proposed algorithm.
Fast superpixel segmentation by iterative edge refinement
Authors: Zhu Song , Cao Danhua , Jiang Shixiong , Wu Yubin , Hu Pan
Published: January 2015

The superpixel, as an important pre‐processing technique, has been successfully used in many vision applications. Introduced is a fast superpixel method called iterative edge refinement (IER). The image was first initialised as regular grids, and then concentration was on unstable pixels and relabelling them iteratively so called unstable pixels, are edge pixels around the moving boundary. It is found that the unstable pixels decrease rapidly during the iterative process, which results in a high speed‐up. Experimental results on the Berkeley BSDS500 dataset show that IER achieves a segmentation performance comparable with the state‐of‐the‐art, and moreover, runs in real‐time on a single Intel i3 CPU at 2.5 GHz.
Pre‐study to detect cancer with RF coil: brain and breast
Authors: Kim Ayrum , Yoo Hyoungsuk
Published: January 2015

With the rising number of elderly people, the cancer rate is also increasing. Thus, to detect cancer in its early stages is very important for increasing survival rates because cancer is one of the leading causes of death. Therefore, diagnosing cancer with a radio frequency (RF) coil that is used to obtain high‐quality medical images from magnetic resonance imaging (MRI) systems is proposed in order to reduce the cost and time needed for the test. Specifically, an RF coil can sense a change in the electrical characteristics of body tissue, such as permittivity and conductivity. This pre‐study shows that RF coils without an MR magnet can be used to determine the difference between normal and abnormal tissues (i.e. a tumour).
Compact lowpass filter with wide stopband using coupled rhombic stubs
Authors: Zhang Bo , Li Shaosheng , Huang Jianming
Published: January 2015

A compact and high selective lowpass filter (LPF) with wide stopband is presented using coupled rhombic stubs. The proposed LPF unit is constructed by loading a rhombic stub on a transmission line. Then, a folded three‐element LPF is proposed to achieve compact size and high selectivity by introducing coupling between adjacent rhombic stubs. The operating mechanism of the filter is investigated and explained, by adopting the physically‐based LC‐equivalent circuit model. The implemented final LPF exhibits a wide stopband of up to 11.5 fc with a rejection level of better than 35 dB. Furthermore, the final LPF features a compact size of 0.12λg × 0.10λg, where λg is the guide wavelength of fc, and a very high figure‐of‐merit (FOM) of 27 142.
Spectrum sensing method based on likelihood ratio goodness‐of‐fit test
Authors: Teguig D. , Le Nir V. , Scheers B.
Published: January 2015

A blind spectrum sensing method based on the goodness‐of‐fit (GoF) test using the likelihood ratio is studied. In the proposed method, the χ2 distribution is used for GoF testing. The performance of the method is evaluated through Monte Carlo simulations. It is shown that the proposed spectrum sensing method outperforms the GoF test using Anderson‐Darling and the conventional energy detection tests in the case of a low signal‐to‐noise ratio.
High‐resolution time of arrival estimation for OFDM‐based transceivers
Authors: Makki A. , Siddig A. , Saad M.M. , Bleakley C.J. , Cavallaro J.R.
Published: January 2015

A novel algorithm for time of arrival (TOA) estimation for OFDM‐based transceivers is presented. The algorithm processes the sampled baseband signal to obtain a high‐resolution estimate of the TOA of the OFDM symbol. In the first step, the algorithm obtains a sample‐resolution estimate of the TOA by finding the peak of the absolute value of the cross‐correlation of the in‐phase and quadrature received signals with the known transmitted symbol. In the second step, the algorithm refines this estimate to sub‐sample resolution by estimating the phase delay of the received signal based on the gradient of a linear fit to the phase difference between the transmitted and received sub‐carriers (in the frequency domain). The algorithm was applied to the long training sequence (LTS) symbol of the IEEE wireless local area network (WLAN) 802.11 g preamble. In real‐world experiments, the algorithm was found to achieve a mean TOA estimation error of 49 cm in a low multi‐path line‐of‐sight environment for ranges of 1–7 m.
Probability of complete decoding of random codes for short messages
Authors: Chong Zan Kai , Goi Bok‐Min , Ohsaki Hiroyuki , Ng Bryan , Ewe Hong Tat
Published: January 2015

A random code is a rateless erasure code with a generator matrix of randomly distributed binary values. It encodes a message of k symbols into a potentially infinite number of coded symbols. For asymptotically large k, the tail bound in Kolchin's theorem asserts that the high probability of complete decoding (PCD) is attained almost surely with k + 10 coded symbols. However, for small values of k (short messages) it is unclear if such asymptotics are useful. That the random codes achieve a high PCD with k + 10 coded symbols for small k is demonstrated. In particular, a set of lemmas is established and show that the PCD converges to five decimal digits after k = 30. A theorem extending Kolchin's work is formulated and the theorem is used to explain the complete decoding probabilities of random codes in short messages.
Compact algorithmic time‐to‐digital converter
Authors: Li Shuo , Salthouse Christopher D.
Published: January 2015

Time‐to‐digital converters (TDCs) are an important circuit block in time‐of‐flight sensors, fluorescence lifetime sensors, and self‐calibrating digital circuits. Fine‐resolution TDCs are usually built with chains of delay elements, but this architecture requires large area, conversion time, and power consumption. A novel compact TDC architecture based on the cyclic comparison algorithm is presented, which implemented and tested in the TSMC, 0.35 μm process within a 200 × 200 μm area is demonstrated that the proposed TDC achieves a conversion rate of 10 ns/bit and sub‐picosecond resolution. The measured power is 0.7 mW, taking 100 ns for each bit.
Design of dual‐band transmission line with flexible phase shifts and its applications
Authors: Ren Han , Shao Jin , Zhou Mi , Arigong Bayaner , Ding Jun , Zhang Hualiang
Published: January 2015

A novel dual‐band transmission line with flexible phase shifts is presented. To realise dual‐band operations, the proposed transmission line is constructed by series‐connected coupled lines and open‐ended stubs. Using this structure, flexible characteristic impedances and electrical lengths can be designed to operate at two frequencies. Moreover, the proposed dual‐band transmission line features a wide range of realisable frequency ratios and a flexible structure. For practical applications, a planar dual‐band 3 dB branch‐line coupler operating at 2/5.2 GHz is designed using the proposed dual‐band transmission line. The simulation and measurement results agree very well with the design theory.
Virtual line‐shafting control for permanent magnet synchronous motor systems using sliding‐mode observer
Authors: Zhang Changfan , He Jing , Jia Lin , Xu Chengjie , Xiao Yuanyuan
Published: January 2015

This study presents a novel observer‐based electronic line‐shafting control strategy for permanent magnet synchronous motor systems. Adopting the sliding‐mode variable structure technology, the proportional–integral speed controller for every servo unit is designed, followed by design of two cascades connected observers, in order to improve the system synchronisation performance when a large load disturbance occurs. The load torque observer transmits the observed load torque value instead of the calculated one back to the virtual shafting, which reflects the dynamic relationships of all the virtual or slave shafts more accurately. Another load torque derivative observer feeds the observed value forward to the corresponding sliding‐mode controller for reducing the switching gain. The proposed control system is proved stable by Lyapunov stability theory, and simulation results show the strategy is effective on reducing sliding‐mode chattering and achieving higher synchronisation precision.
Structure and dynamical intra-molecular heterogeneity of star polymer melts above glass transition temperature
Authors: Chremos Alexandros , Glynos Emmanouil , Green Peter F.
Published: January 2015

Structural and dynamical properties of star melts have been investigated with molecular dynamics simulations of a bead-spring model. Star polymers are known to be heterogeneous, but a systematic simulation study of their properties in melt conditions near the glass transition temperature was lacking. To probe their properties, we have expanded from linear to star polymers the applicability of Dobkowski’s chain-length dependence correlation function [Z. Dobkowski, Eur. Polym. J. 18, 563 (1982)]. The density and the isokinetic temperature, based on the canonical definition of the laboratory glass-transition, can be described well by the correlation function and a subtle behavior manifests as the architecture becomes more complex. For linear polymer chains and low functionality star polymers, we find that an increase of the arm length would result in an increase of the density and the isokinetic temperature, but high functionality star polymers have the opposite behavior. The effect between low and high functionalities is more pronounced for short arm lengths. Complementary results such as the specific volume and number of neighbors in contact provide further insights on the subtle relation between structure and dynamics. The findings would be valuable to polymer, colloidal, and nanocomposites fields for the design of materials in absence of solution with the desired properties.
Optical characterization and confocal fluorescence imaging of mechanochromic acrylate polymers
Authors: van Horn M. , Smith P. , Mason B. P. , Hemmer J. R. , Read de Alaniz J. , Hooper J. P. , Osswald S.
Published: January 2015

The development of mechanochromic molecules has opened new pathways for the study of localized stress and failure in polymers. Their application as stress or temperature diagnostics, however, requires suitable measurement techniques capable of detecting the force- and temperature-sensitive chemical species with high spatial resolution. Confocal imaging techniques offer excellent spatial resolution but the energy input during these measurements can itself affect the activation state of the mechanochromic species. Here, we present a systematic study of the effects of laser-based imaging on the activation and fluorescence behavior of mechanochromic spiropyran (SP) integrated into poly(methyl acrylate) (PMA) and poly(methyl methacrylate) matrices using a confocal Raman microspectrometer. Localized stress and temperature activation were studied by means of high-rate compressive loading and dynamic fracture. Laser illumination of SP in PMA revealed a strong excitation wavelength- and power-dependence. Suitable correction functions were established and used to account for the observed laser effects. The presented study demonstrates that confocal imaging using conventional Raman spectrometers is a powerful characterization tool for localized stress analysis in mechanochromic polymers, offering quantifiable information on the activation state with high spatial resolution. However, laser-mechanophore interactions must be well understood and effects of laser excitation and exposure times must be taken into consideration when interpreting the obtained results.
Anomalous Fe diffusion in Si-ion-implanted β–Ga2O3 and its suppression in Ga2O3 transistor structures through highly resistive buffer layers
Authors: Wong Man Hoi , Sasaki Kohei , Kuramata Akito , Yamakoshi Shigenobu , Higashiwaki Masataka
Published: January 2015

The thermal behavior of Fe as a compensating acceptor impurity in β-Ga2O3 (010) was studied in view of growing interests in semi-insulating Fe-doped Ga2O3 substrates for the realization of high-performance Ga2O3 field-effect transistors (FETs). An anomalous redistribution of Fe beyond the extent of intrinsic thermal diffusion was revealed by secondary ion mass spectroscopy in device-relevant structures where Ga2O3 grown homoepitaxially on Fe-doped substrates was doped by Si ion (Si+) implantation and annealed at high temperatures. The enhanced Fe diffusion was attributed to an athermal process involving intrinsic defects from the region of implantation damage. An undoped Ga2O3 buffer between the Si+-implanted layer and the Fe-doped substrate effectively suppressed Fe outdiffusion by protecting the substrate against unintentional ion damage or defects from a remote source, thereby preserving the electrical integrity of the Si-doped material. Temperature-dependent current-voltage measurements indicated that the undoped Ga2O3 buffer was highly resistive with inter-device leakage attributable to surface conduction via a variable-range hopping mechanism. The buffer scheme, together with dielectric passivation to eliminate surface leakage, was proposed to constitute an integral process module for future lateral Ga2O3 FET devices.
Sensitivity of CoSi2 precipitation in silicon to extra-low dopant concentrations. I. Experiment
Authors: Fortuna F. , Ruault M.-O. , Borodin V. A. , Ganchenkova M. G. , Kaïtasov O.
Published: January 2015

We demonstrate that the precipitation of cobalt disilicide phase in silicon during high-temperature (500 °C and 650 °C) implantation is noticeably affected by impurities of phosphorus and boron. Measurements of B-type CoSi2 cluster sizes and number densities as a function of implantation dose indicate that the number density of clusters progressively increases as the phosphorus concentration increases from 7 × 1011 to 8 × 1013 cm−3. A tentative explanation of these observations is proposed based on the previously suggested mechanism of precipitate nucleation, and on the results of first principles calculations summarized in Paper II, published as a follow-up paper. The results imply that utmost care is to be taken when dealing with transition metal precipitation during ion implantation into silicon because variations in the dopant content can affect the reproducibility of results even at extremely low dopant concentrations.
Time-dependent domain wall nucleation probability in field-coupled nanomagnets with perpendicular anisotropy
Authors: Breitkreutz Stephan , Fischer Andreas , Kaffah Silmi , Weigl Stephanie , Eichwald Irina , Ziemys Grazvydas , Schmitt-Landsiedel Doris , Becherer Markus
Published: January 2015

In this paper, the domain wall (DW) nucleation time and the DW nucleation probability of field-coupled magnets with perpendicular magnetic anisotropy are measured by experiment. A well-established Arrhenius model based on thermally activated magnetization reversal is applied to describe the time-dependent DW nucleation probability. Magneto-optical microscopy(MOKE) is used in the experiments to determine the DW nucleation time and the DW nucleation probability in a pNML inverter structure. The DW propagation speed is measured in order to calculate the required DW propagation time for entire magnetization reversal of pNML logic gates. Experimental results are compared to the derived model. Our results show that the interaction in pNML logic gates plays a significant role for the time-dependent DW nucleation probability and therefore for the reliability of field-coupled circuits.
Communication: Nanosecond folding dynamics of an alpha helix: Time-dependent 2D-IR cross peaks observed using polarization-sensitive dispersed pump-probe spectroscopy
Authors: Panman Matthijs R. , van Dijk Chris N. , Meuzelaar Heleen , Woutersen S.
Published: January 2015

We present a simple method to measure the dynamics of cross peaks in time-resolved two-dimensional vibrational spectroscopy. By combining suitably weighted dispersed pump-probe spectra, we eliminate the diagonal contribution to the 2D-IR response, so that the dispersed pump-probe signal contains the projection of only the cross peaks onto one of the axes of the 2D-IR spectrum. We apply the method to investigate the folding dynamics of an alpha-helical peptide in a temperature-jump experiment and find characteristic folding and unfolding time constants of 260 ± 30 and 580 ± 70 ns at 298 K.
Controllable formation of nano-crystalline in Sb4Te films by Zn doping
Authors: Wang Guoxiang , Chen Yimin , Shen Xiang , Lu Yegang , Dai Shixun , Nie Qiuhua , Xu Tiefeng
Published: January 2015

We investigated the optical, electrical, and thermal properties of Zn-doped Sb4Te films for application in phase change memory. Together with well-documented results of Zn-doped Sb2Te3, Sb2Te, Sb7Te3, and Sb3Te systems, we plotted the ternary amorphous-phase forming-region of Zn-Sb-Te. Zn-doping increased the crystallization temperature and data retention ability of Sb4Te films. We identified the optimal composition as Zn28.6(Sb4Te)71.4, which presents reversible optical performance between the amorphous and crystalline states. The minimum time for onset crystallization was 15 ns and the required pulse width for complete crystallization was 165 ns at 70 mW. Furthermore, in all of the Zn-doped Sb-Te films, it was confirmed that Zn-doping can effectively control the growth of nano-crystalline grains and allows only a single phase to form during crystallization.
Note: Effect of hot liner in producing 40,48Ca beam from RIKEN 18-GHz electron cyclotron resonance ion source
Authors: Ozeki K. , Higurashi Y. , Kidera M. , Nakagawa T.
Published: January 2015

In order to produce a high-intensity and stable 48Ca beam from the RIKEN 18-GHz electron cyclotron resonance ion source, we have begun testing the production of a calcium beam using a micro-oven. To minimize the consumption rate of the material (48Ca), we introduced the “hot liner” method and investigated the effect of the liner on the material consumption rate. The micro-oven was first used to produce the 48Ca beam for experiments in the RIKEN radioisotope beam factory, and a stable beam could be supplied for a long time with low consumption rate.
Synthesis and biological activities of the amide derivative of aplog-1, a simplified analog of aplysiatoxin with anti-proliferative and cytotoxic activities
Authors: Hanaki Yusuke , Yanagita Ryo C , Sugahara Takahiro , Aida Misako , Tokuda Harukuni , Suzuki Nobutaka , Irie Kazuhiro
Published: January 2015

Aplog-1 is a simplified analog of the tumor-promoting aplysiatoxin with anti-proliferative and cytotoxic activities against several cancer cell lines. Our recent findings have suggested that protein kinase Cδ (PKCδ) could be one of the target proteins of aplog-1. In this study, we synthesized amide-aplog-1 (3), in which the C-1 ester group was replaced with an amide group, to improve chemical stability in vivo. Unfortunately, 3 exhibited seventy-fold weaker binding affinity to the C1B domain of PKCδ than that of aplog-1, and negligible anti-proliferative and cytotoxic activities even at 10−4 M. A conformational analysis and density functional theory calculations indicated that the stable conformation of 3 differed from that of aplog-1. Since 27-methyl and 27-methoxy derivatives (1, 2) without the ability to bind to PKC isozymes exhibited marked anti-proliferative and cytotoxic activities at 10−4 M, 3 may be an inactive control to identify the target proteins of aplogs.
Screening for a gene deletion mutant whose temperature sensitivity is suppressed by FK506 in budding yeast and its application for a positive screening for drugs inhibiting calcineurin
Authors: Kume Kazunori , Koyano Takayuki , Takata Junpei , Wakabayashi Ko , Mizunuma Masaki , Miyakawa Tokichi , Hirata Dai
Published: January 2015

Calcineurin, which is a Ca2+/calmodulin-dependent protein phosphatase, is a key mediator in calcium signaling in diverse biological processes and of clinical importance as the target of the immunosuppressant FK506. To identify a mutant(s) in which calcineurin is activated, inhibiting cellular growth as a result, we screened for a mutant(s) whose temperature sensitivity would be suppressed by FK506 from the budding yeast non-essential gene deletion library. We found that the temperature sensitivity of cells in which the conserved Verprolin VRP1 gene had been deleted, which gene is required for actin organization and endocytosis, was suppressed by either FK506 or by cnb1 deletion. Indeed, the calcineurin activity increased significantly in the ∆vrp1 cells. Finally, we demonstrated that the ∆vrp1 strain to be useful as an indicator in a positive screening for bioactive compounds inhibiting calcineurin.
Incorporating the patient’s voice into electronic health records through patient-reported outcomes as the “review of systems”
Authors: Chung Arlene E , Basch Ethan M
Published: January 2015

Owing to lack of standardization for eliciting patient symptoms, the limited time available during clinical encounters, and the often-competing priorities of patients and providers, providers may not appreciate the full spectrum of the patient’s symptom experience. Using electronically collected patient-reported outcomes to capture the review of system outside of the clinic visit may not only improve the efficiency, completeness, and accuracy of data collection for the review of system, but also provide the opportunity to operationalize incorporating the patient’s voice into the electronic health record. While the necessary technology is already available, multiple stakeholders, including electronic health record vendors, clinicians, researchers, and professional societies, need to align their interests before this can become a widespread reality.