bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid and simultaneous detection of linear chromosome and large plasmids in Proteobacteria
Authors: Ramírez‐Bahena Martha Helena , Nesme Xavier , Muller Daniel 
Published: February 2012

AbstractBacterial genomic architectures are complex and play important roles in genome evolution. While most bacterial lineage genomes contain a single chromosome often accompanied by plasmids, more and more genomes are described as harboring a linear or a second chromosome. Thus, the development of bacterial genomics leads to the study of bacterial genome architectures. In order to avoid laborious techniques combining several methods, we developed an original plug‐free pulsed field gel electrophoresis procedure, that enabled us to co‐characterize reproducibly the presence of linear chromosomes and plasmids ranging between 30 kb and 2000 kb in various proteobacterial lineages. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flagella and bacterial pathogenicity
Authors: Duan Qiangde , Zhou Mingxu , Zhu Liqian , Zhu Guoqiang 
Published: February 2012

AbstractAs locomotive organelles, flagella allow bacteria to move toward favorable environments. A flagellum consists of three parts: the basal structure (rotary motor), the hook (universal joint), and the filament (helical propeller). For ages, flagella have been generally regarded as important virulence factors, mainly because of their motility property. However, flagella are getting recognized to play multiple roles with more functions besides motility and chemotaxis. Recent evidence has pinpointed that the bacterial flagella participate in many additional processes including adhesion, biofilm formation, virulence factor secretion, and modulation of the immune system of eukaryotic cells. This mini‐review summarizes data from recent studies that elucidated how flagella, as a virulence factor, contribute to bacterial pathogenicity.
Characterization of an antifungal compound produced by Bacillus sp. strain A5F that inhibits Sclerotinia sclerotiorum
Authors: Kumar Ankit , Saini Sandeep , Wray Victor , Nimtz Manfred , Prakash Anil , Johri B. N. 
Published: February 2012

AbstractA potential antagonist, Bacillus sp. strain A5F was isolated from soybean rhizosphere following in vitro dual plate screening. The bacterium displayed strong inhibitory activity in vitro against soybean stem rot pathogen, Sclerotinia sclerotiorum. The culture supernatant of strain A5F completely suppressed the mycelial growth of the pathogen, indicating that suppression was due to the presence of antifungal compounds in the culture filtrate. The culture filtrate also suppressed other phytopathogenic fungi including Fusarium oxysporum and Macrophomina phaseolina, in vitro suggesting a broad spectrum antagonistic activity against fungal pathogens. Chemical extraction followed by chromatographic analysis resulted in two antifungal fractions. The high resolution‐electron spin ionization‐mass spectrometry (HR‐ESI‐MS) and Nuclear Magnetic Resonance (1D and 2D1H) spectra of these antifungal fractions revealed the presence of antifungal compounds, one of which showed similarity to bacillomycin D. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimization of indigo production by a newly isolated Pseudomonas sp. QM
Authors: Qu Yuanyuan , Ma Qiao , Zhang Xuwang , Zhou Hao , Li Xinliang , Zhou Jiti 
Published: February 2012

AbstractOptimization of indigo production process from indole using a newly isolated phenol‐degrading bacterial strain was performed by Plackett‐Burman design and response surface methodology. The strain designated as QM was identified as Pseudomonas sp. according to 16S rDNA analysis. Spectrum analysis of indole biotransformation products revealed the presence of indigo and a by‐product indirubin. To improve indigo yield, Plackett‐Burman design was used to select significant factors from 8 viriables. Then response surface methodology based on a 23 central composite design was used to further optimize the transformation process. Under the optimal conditons, strain QM can produce 27.20 mg/l indigo after 24 h cultivation at 30 °C, which was 151.3% higher than that from the initial conversion condition. The results indicated that Pseudomonas sp. QM should be a potential candidate for indigo industial production. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genetic epidemiology and heritability of AIS: A study of 415 Chinese female patients
Authors: Tang Nelson L.S. , Yeung Hiu‐Yan , Hung Vivian W.Y. , Di Liao Chen , Lam Tsz‐Ping , Yeung Hau‐Man , Lee Kwong‐Man , Ng Bobby Kin‐Wah , Cheng Jack Chun‐Yiu 
Published: February 2012

AbstractRecent familial segregation studies supported a multifactorial genetic model for the etiology of adolescent idiopathic scoliosis (AIS). However, the extent of quantitative genetic effects, such as heritability, have not been fully evaluated. This genetic epidemiology study examined the sibling recurrent risk and heritability of AIS in first‐degree relatives of 415 Chinese female patients, which is up to now the largest cohort. They were first diagnosed by community screening program and compared to 203 age‐matched normal controls. Out of the total 531 sibs of AIS cases, 94 sibs had scoliosis (sibling recurrence risk = 17.7%). The prevalence of AIS among male and female sibs of an index case were 11.5% (95% CI = 7.5–15.5) and 23.0% (95% CI = 18.1–27.9), respectively. Female sibs of an index case had an increased risk of 8.9‐fold (95% CI = 3.2–34.4) for developing AIS. These recurrent risks were significantly higher than the risk in the control group (p < 0.0001). Overall, heritability was estimated to be 87.5 ± 11.1%. The results confirmed the prevailing impression of strong genetic influence on the risk of AIS. Here we provided a large‐scale study for the genetic aggregation estimates in an Asian population for the first time. The finding also positioned AIS among other common disease or complex traits with a high heritability. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1464–1469, 2012
Obligate crayfish burrow use and core habitat requirements of crawfish frogs
Authors: Heemeyer Jennifer L. , Williams Perry J. , Lannoo Michael J. 
Published: February 2012

AbstractCrawfish frogs (Lithobates areolatus) have experienced declines across large portions of their former range. These declines are out of proportion to syntopic wetland‐breeding amphibian species, suggesting losses are resulting from unfavorable aspects of non‐breeding upland habitat. Crawfish frogs get their common name from their affinity for crayfish burrows, although the strength of this relationship has never been formally assessed. We used radiotelemetry to address 4 questions related to upland burrow dwelling in crawfish frogs: 1) what burrow types are used and how do they function to affect crawfish frog survivorship; 2) what are the physical characteristics and habitat associations of crawfish frog burrows; 3) what are the home range sizes of crawfish frogs when burrow dwelling; and 4) where are crawfish frog burrows situated with respect to breeding wetlands? We tracked crawfish frogs to 34 burrows, discovered another 7 occupied burrows, and therefore report on 41 burrows. Crawfish frogs exclusively occupied crayfish burrows as primary burrows, which they inhabited for an average of 10.5 months of the year. With one exception, crawfish frogs also used crayfish burrows as secondary burrows—temporary retreats occupied while exhibiting breeding migrations or ranging forays. Burrows were exclusively located in grassland habitats, although crawfish frogs migrated through narrow woodlands and across gravel roads to reach distant grassland primary burrow sites. Home range estimates while inhabiting burrows were 0.05 m2(the area of the burrow entrance plus the associated feeding platform) or 0.01 m3(the estimated volume of their burrow). Crawfish frog burrows were located at distances up to 1,020 m from their breeding wetlands. To protect crawfish frog populations, we recommend a buffer (core habitat plus terrestrial buffer) of at least 1.2 km around each breeding wetland. Within this buffer, at least 3 critical habitat elements must be present: 1) extensive grasslands maintained by prescribed burning and/or logging, 2) an adequate number of upland crayfish burrows, and 3) no soil disturbance of the sort that would destroy crayfish burrow integrity. © 2012 The Wildlife Society.
Music and lexical tone perception in chinese adult cochlear implant users
Authors: Wang Shuo , Liu Bo , Dong Ruijuan , Zhou Yun , Li Jing , Qi Beier , Chen Xueqing , Han Demin , Zhang Luo 
Published: February 2012

AbstractObjectives/Hypothesis:The present study's aim was to assess the music perception ability for Chinese adult cochlear implant users and to investigate the correlation between music and Mandarin‐Chinese lexical tone perception.Study Design:Case‐control study.Methods:Twenty normal‐hearing and 21 adult cochlear implant users participated in the Musical Sounds in Cochlear Implants (MuSIC) perception test, including six objective and two subjective musical subtests. The comparison of music perception performance was made between normal‐hearing and cochlear implant subjects. Sixteen of the 21 cochlear implant users also performed a tone identification test to investigate the correlation between music and tone perception.Results:Cochlear implant users performed significantly worse than normal‐hearing subjects on pitch discrimination, instrument identification, and instrument detection tests, whereas close to normal‐hearing subjects on melody discrimination, chords discrimination, rhythm discrimination, and emotion and dissonance rating subtests. Lexical tone perception was significantly correlated with pitch discrimination, melody discrimination, and instrument identification tests. Duration of hearing aid use was found to be correlated with pitch discrimination ability of cochlear implant users.Conclusions:Chinese postlingually deafened cochlear implant users performed significantly poorer in pitch discrimination and timbre perception tasks than normal‐hearing listeners. Lexical tone perception was found to be significantly correlated with music pitch perception, supporting the notion that tone and music perception may share a similar pitch perception mechanism.
Competitive Cellular Uptake of Nanoparticles Made From Polystyrene, Poly(methyl methacrylate), and Polylactide
Authors: Höcherl Anita , Dass Martin , Landfester Katharina , Mailänder Volker , Musyanovych Anna 
Published: February 2012

AbstractThe uptake behavior of negatively charged fluorescent nanoparticles made from different polymers (PS, PMMA, and PLLA) is studied on HeLa cells. All particles are obtained by the miniemulsion process using sodium dodecylsulfate as anionic surfactant. The size of the particles is in the range 105–125 nm. Cell uptake is analyzed by flow cytometry and reveals a higher uptake of PLLA particles compared to PMMA and PS particles. In competitive uptake studies two different types of particles are co‐incubated with the HeLa cells; the results indicate a mutual influence of the particles on their uptake behavior. A reduced internalization of PLLA particles in the presence of PS particles is observed, although neither the co‐incubation of PMMA and PLLA nor of PMMA and PS shows similar effect.magnified image
Preparation of Biodegradable Polylactide Microparticles via a Biocompatible Procedure
Authors: Levato Riccardo , Mateos‐Timoneda Miguel A. , Planell Josep A. 
Published: February 2012

AbstractPLA MPs are prepared via a novel and toxic‐chemical‐free fabrication route using ethyl lactate, a green solvent and FDA‐approved aroma. MPs are obtained by a solution jet break‐up and solvent displacement method. Adjusting flow parameters allows the tuning of MPs size between 60 and 180 µm, with reduced polydispersity. Morphological analysis shows microporous particles with Janus‐like surface. A fluorophore is successfully loaded into the MPs during their formation step. This versatile green solvent‐based procedure is proven to be suitable for drug encapsulation and delivery applications. The method may be extended to different droplet generation techniques.magnified image
Influence of SWNTs on the Preferential Alignment of Molecular Moieties in PVA Fibers
Authors: Ford Ericka Nicole Johnson , Minusa Marilyn Lillith , Liu Tao , Choi Ji Il , Jang Seung Soon , Kumar Satish 
Published: February 2012

AbstractThe alignment of electron‐donating moieties in SWNT‐embedded PVA fibers is characterized using infrared dichroism and polarized Raman spectroscopy. The SWNT alignment is found to influence the preferential alignment of PVA functional groups and solvent molecules with respect to the fiber axis. Furthermore, the fraction of oriented functional moieties depends more on the SWNT alignment than on the PVA chain orientation. Charge transfer between functional moieties and SWNTs results in molecular adhesion between the SWNTs and interacting groups, as confirmed by DFT calculations.
Ethylene‐co‐Norbornene Copolymers Grafted Carbon Nanotube Composites by In Situ Polymerization
Authors: Boggioni Laura , Scalcione Giulia , Ravasio Andrea , Bertini Fabio , D'Arrigo Cristina , Tritto Incoronata 
Published: February 2012

AbstractVinyl functionalized multiwalled carbon nanotubes (MWCNT‐vinyl) are synthesized and used as monomers to prepare poly(ethylene‐co‐norbornene)‐grafted carbon nanotube composites by in situ polymerization with [Ti(η5‐C5Me5)(NCtBu2)Cl2] activated with methylalumoxane (MAO). The glass transition temperatures (Tg) of grafted MWCNT composites are more than 30 °C higher than those of copolymers. This difference is rationalized by the immobilization of the copolymer chain to the MWCNT surface by a covalent bond. The Young's modulus is shown to increase by more than 200% compared to poly(ethylene‐co‐norbornene) by incorporating 3.4 wt% functionalized MWCNT.
Fast copper catalyzed living radical polymerization of acrylonitrile utilizing a high concentration of radical initiator
Authors: Liu Xiao‐hui , Wang Jin , Yang Jian‐shi , An Shu‐lin , Ren Yuan‐lin , Yu Yun‐hai , Chen Peng 
Published: February 2012

AbstractThis article first reports a fast and controlled living radical polymerization (LRP) of acrylonitrile, evidenced by 81.3% monomer conversion within 40 min and well‐defined the polymers with a narrow polydispersity index (PDI) range of 1.14−1.38. This was achieved by utilizing azobis(isobutyronitrile) as radical initiator with a high concentration up to 190 mM and CuBr2 as catalyst with a very low concentration down to 50 ppm. The polymerization displayed typical LRP characteristics, including pseudo first‐order kinetics of polymerization, the linear increase of number‐average molecular weights (MWs), low PDI values. The influence of various experimental components, radical initiator concentration, catalyst concentration, and reaction temperature, on the polymerization reaction and MW as well as PDI has been investigated in detail. 1H NMR and gel permeation chromatography analyses as well as chain extension reaction confirmed the very high chain‐end functionality of the resultant polymer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Effect of molar mass and regioregularity on the photovoltaic properties of a reduced bandgap phenyl‐substituted polythiophene
Authors: Ouhib Farid , Dupuis Guillaume , de Bettignies Rémi , Bailly Séverine , Khoukh Abdel , Martinez Hervé , Desbrières Jacques , Hiorns Roger C. , Dagron‐Lartigau Christine 
Published: February 2012

AbstractAmong the numerous reduced bandgap polymers currently being developed, poly[3‐(4‐octylphenyl)thiophene)]s (POPT) may present attractive properties for organic solar cells due to its facile preparation and improved absorption with respect to poly(3‐hexylthiophene). This article appraises methods of preparation, including the use of diphenyl ether as a reaction medium, and discusses the effects of variations in molar masses, from about 3200 to 65,000 g mol−1 and regioregularity on its optoelectronic properties. The photovoltaic properties of POPT with [6,6]‐phenyl C61 butyric acid methyl ester (PCBM) in bulk heterojunction devices are also discussed in the light of morphological variations, as indicated by atomic force microscopy characterizations. With an initial screening of conditions, namely POPT:PCBM ratios and deposition solvent, a power conversion efficiency of 1.58% was obtained using a relatively high molar mass POPT sample. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Systematic study on chemical oxidative and solid‐state polymerization of poly(3,4‐ethylenedithiathiophene)
Authors: Chen Shuai , Lu Baoyang , Duan Xuemin , Xu Jingkun 
Published: February 2012

AbstractSystematic research on the synthesis, chemical oxidative polymerization of 3,4‐ethylenedithiathiophene (EDTT) in the presence of surfactants or not, and solid‐state polymerization of 2,5‐dibromo‐3,4‐ethylenedithiathiophene (DBEDTT) and 2,5‐diiodo‐3,4‐ethylenedithiathiophene (DIEDTT) under solventless and oxidant‐free conditions has been investigated. Effects of oxidants (Fe3+ salts, persulfate salts, peroxides, and Ce4+ salts), solvents (H2O, CH3CN/H2O, and CH3CN), surfactants, and so forth on polymerization reactions and properties of poly(3,4‐ethylenedithiathiophene) (PEDTT) were discussed. Characterizations indicated that FeCl3 was more suitable oxidant for oxidative polymerization of EDTT, while CH3CN was a better solvent to form PEDTT powders with higher yields and electrical conductivities. Dispersing these powders in aqueous polystyrene sulfonic acid (PSSH) solution showed better stability and film‐forming property than sodium dodecylsulfate and sodium dodecyl benzene sulfonate. Oxidative polymerization of EDTT in aqueous PSSH solutions formed the solution processable PEDTT dispersions with good storing stability and film‐forming performance. Solvent treatment showed indistinctive effect on electrical conductivity of free‐standing PEDTT films. As‐formed PEDTT synthesized from solid‐state polymerization showed similar electrical conductivity, poorer stability, but better thermoelectric property than oxidative polymerization. Contrastingly, PEDTT synthesized from DIEDTT showed higher electrical conductivity (0.18 S cm−1) than DBEDTT which showed better thermoelectric property with higher power factor value (6.7 × 10−9 W m−1 K−2). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Preparation of main‐chain imidazolium‐functionalized amphiphilic block copolymers through combination of condensation polymerization and nitroxide‐mediated free radical polymerization and their micelle study
Authors: Li Xue , Ni Xufeng , Liang Zhenhua , Shen Zhiquan 
Published: February 2012

AbstractMain‐chain imidazolium‐functionalized amphiphilic block copolymers (PIL‐b‐PS) consisting of polyionic liquid (PIL) and polystyrene (PS) blocks have been first synthesized by condensation polymerization combined with nitroxide‐mediated free radical polymerization (NMP). The di‐functional imidazolium‐based ionic liquid (IL) having both hydroxyl and ester end groups was synthesized through Michael addition between imidazole and methylacrylate (MA) and further quaternization by 2‐chloroethanol. The HTEMPO (4‐hydroxy‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy) terminated polyionic liquid (HTEMPO‐PIL) as the hydrophilic block was prepared by condensation polymerization of di‐functional imidazolium IL and HTEMPO at a certain ratio. The hydrophobic PS block was synthesized by controlled radical polymerization of styrene using HTEMPO‐PIL through NMP, resulting PIL‐b‐PS block copolymers. The structure of block copolymers obtained has been characterized and verified by FTIR, 1H NMR, and size exclusion chromatography analyses. In addition, the morphology and size of the micelles formed by PIL‐b‐PS block copolymers in water were investigated by transmission electron microscopy and dynamic light scattering. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Fluorene‐ and benzimidazole‐based blue light‐emitting copolymers: Synthesis, photophysical properties, and PLED applications
Authors: Zhu Haifeng , Tong Hui , Gong Yongyang , Shao Shiyang , Deng Chunmei , Yuan Wang Zhang , Zhang Yongming 
Published: February 2012

AbstractBlue light‐emitting materials are receiving considerable academic and industrial interest due to their potential applications in optoelectronic devices. In this study, blue light‐emitting copolymers based on 9,9′‐dioctylfluorene and 2,2′‐(1,4‐phenylene)‐bis(benzimidazole) moieties were synthesized through palladium‐catalyzed Suzuki coupling reaction. While the copolymer consisting of unsubstituted benzimidazoles (PFBI0) is insoluble in common organic solvents, its counterpart with N‐octyl substituted benzimidazoles (PFBI8) enjoys good solubility in toluene, tetrahydrofuran, dichloromethane (DCM), and chloroform. The PFBI8 copolymer shows good thermal stability, whose glass transition temperature and onset decomposition temperature are 103 and 428 °C, respectively. Its solutions emit blue light efficiently, with the quantum yield up to 99% in chloroform. The electroluminescence (EL) device of PFBI8 with the configuration of indium‐tin oxide/poly(ethylenedioxythiophene):poly(styrene sulfonic acid)/PFBI8/1,3,5‐tris(1‐phenyl‐1H‐benzimidazole‐2‐yl)benzene/LiF/Al emits blue light with the maximum at 448 nm. Such unoptimized polymer light‐emitting diode (PLED) exhibits a maximum luminance of 1534 cd/m2 with the current efficiency and power efficiency of 0.67 cd/A and 0.20 lm/W, respectively. The efficient blue emission and good EL performance make PFBI8 promising for optoelectronic applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
ATRP of styrene catalyzed by elemental Fe(0) and Br2: An easy and economical ATRP process
Authors: Yu Huali , Zhang Zhengbiao , Cheng Zhenping , Zhu Jian , Zhou Nianchen , Zhang Wei , Zhu Xiulin 
Published: February 2012

AbstractIn this work, zero‐valent iron (Fe(0)) (powder or wire) and elemental bromine (Br2) were used as the catalysts for atom transfer radical polymerization (ATRP) of styrene (St) without any additional initiator at 110 °C. The polymerizations happened with controlled evidence at appropriate molar ratio of Fe(0) to Br2: a remarkable increase of molecular weights with St conversions, the narrow molecular weight distributions and living polymer chains end‐capped by Br. More Br2 or less Fe(0) led to a slow polymerization rate but an improved control over molecular weights. After examining the polymer chain ends by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, it was concluded that the polymerization was initiated by thermal self‐initiation, and regulated by the in situ generated FeIIIBr3. The results suggested that the Fe(0)/Br2 catalyzing polymerization was a classical ATRP process with easier operation and more economical components. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012