bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐temperature oxidation of aniline to highly ordered polyaniline–sulfate salt with a nanofiber morphology and its use as electrode materials in symmetric supercapacitors
Authors: Palaniappan Srinivasan , Sydulu Singu Bal , Prasanna Taneeru Lakshmi , Srinivas Pabba 
Published: November 2010

AbstractIn this study, for the first time, aniline was oxidized by ammonium persulfate (APS) at higher temperatures without any protic acid, and APS acted as an oxidizing agent and a protonating agent. During the oxidation of aniline by APS, sulfuric acid formation occurred, and the sulfuric acid was incorporated into polyaniline (PANI) as a dopant. PANI–sulfate samples were characterized by IR spectroscopy, X‐ray diffraction, and scanning electron microscopy techniques. In this methodology, a highly ordered PANI–sulfate salt (H2SO4) with a nanofiber morphology was synthesized. Interestingly, a PANI base was also obtained with a highly ordered structure with an agglomerated netlike nanofiber morphology. PANI–H2SO4 was used as an electrode material in a symmetric supercapacitor cell. Electrochemical characterization, including cyclic voltammetry (CV), charge–discharge (CD), and impedance analysis, was carried out on the supercapacitor cells. In this study, the maximum specific capacitance obtained was found to be 273 F/g at 1 mV/s. Scan rate from cyclic voltammetry and 103 F/g at 1 mA discharge current from CD measurement. Impedance measurement was carried out at 0.6 V, and it showed a specific capacitance of 73.2 F/g. The value of the specific capacitance and energy and power densities for the PANI–H2SO4 system were calculated from CD studies at a 5‐mA discharge rate and were found to be 43 F/g, 9.3 W h/kg, and 500 W/kg, respectively, with 98–100% coulombic efficiency. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Thermal and mechanical properties of anhydride‐cured epoxy resins with different contents of biobased epoxidized soybean oil
Authors: Altuna F. I. , Espósito L. H. , Ruseckaite R. A. , Stefani P. M. 
Published: November 2010

AbstractThermosetting resins were synthesized by the partial replacement of the synthetic epoxy prepolymer based on diglycidyl ether of bisphenol A (DGEBA) with increasing amounts of epoxidized soybean oil (ESO) with methyltetrahydrophthalic anhydride as a crosslinking agent and 1‐methyl imidazole as an initiator. Calorimetric studies showed a drop in the reaction heat with ESO content; this was associated with the lower reactivity of oxirane rings in ESO due to steric constrains. The effects of the replacement of increasing amounts of synthetic DGEBA with ESO on the network properties, such as the storage modulus (E′) in the glassy and rubbery regions, glass‐transition temperature (Tg), and impact and compressive properties were examined. All formulations were transparent, although phase‐separated morphologies were evidenced by scanning electron microscopy observations. The intensity of the transmitted light passed to a minimum at a short reaction time associated with the cloud point and then increased continuously until the refractive index of the dispersed phase approximated that of the continuous phase at complete conversion. The combination of DGEBA with 40 wt % ESO resulted in a resin with an optimum set of properties; E′ in the glassy state was 93% of that of the neat DGEBA resin, Tg decreased only about 11°C, and the impact strength increased about 38% without a loss of transparency. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of annealing on the crystallization and properties of electrospun polylatic acid and nylon 6 fibers
Authors: Cho Ah‐Ra , Shin Dong Myeong , Jung Hyun Wook , Hyun Jae Chun , Lee Joo Sung , Cho Daehwan , Joo Yong Lak 
Published: November 2010

AbstractElectrospinning experiments for solutions of two polymers with different crystallization rates, polylatic acid (PLA), and nylon 6 solutions have been carried out. Hexafluoroisopropanol (HFIP) was used as a common solvent to dissolve both PLA and nylon 6. Using the fact that nylon 6 has the faster crystallization rate than PLA, the effect of thermal annealing conditions on the crystal structures of two electrospun fibers has mainly been studied via thermal and mechanical analysis. First, optimal conditions for the formation of uniform nanofibers have been determined by observing their morphology and rheological properties. Thermal analysis revealed that PLA as‐spun fiber exhibits cold crystallization due to insufficient crystal growth in spinline. Also, the effect of thermal annealing on the structural change of nylon 6 fibers including the degree of flow‐induced crystallization is totally different from that of PLA fibers. Finally, tensile measurements of annealed fibers show that the ultimate tensile strength and Young's modulus gradually increases with increasing annealing time for both PLA and nylon 6 mats, resulting from the further growth of crystal structures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Model‐based linear clustering
Authors: Yan Guohua , Welch William J. , Zamar Ruben H. 
Published: November 2010

AbstractThe authors propose a profile likelihood approach to linear clustering which explores potential linear clusters in a data set. For each linear cluster, an errors‐in‐variables model is assumed. The optimization of the derived profile likelihood can be achieved by an EM algorithm. Its asymptotic properties and its relationships with several existing clustering methods are discussed. Methods to determine the number of components in a data set are adapted to this linear clustering setting. Several simulated and real data sets are analyzed for comparison and illustration purposes. The Canadian Journal of Statistics 38: 716–737; 2010 © 2010 Statistical Society of Canada
Optimal estimation in surrogate outcome regression problems
Authors: Duan Xiaogang , Qin Jing , Wang Qihua 
Published: November 2010

AbstractThe authors consider a double robust estimation of the regression parameter defined by an estimating equation in a surrogate outcome set‐up. Under a correct specification of the propensity score, the proposed estimator has smallest trace of asymptotic covariance matrix whether the “working outcome regression model” involved is specified correct or not, and it is particularly meaningful when it is incorrectly specified. Simulations are conducted to examine the finite sample performance of the proposed procedure. Data on obesity and high blood pressure are analyzed for illustration. The Canadian Journal of Statistics 38: 633–646; 2010 © 2010 Statistical Society of Canada
Heterosynaptic enhancement of the excitability of hippocampal mossy fibers by long‐range spill‐over of glutamate
Authors: Uchida Takeshi , Fukuda Satoshi , Kamiya Haruyuki 
Published: November 2010

AbstractSeveral classes of ionotropic receptors have been reported to depolarize the axonal membrane of hippocampal mossy fibers. Both kainate receptors and GABAA receptors are localized on axons and/or presynaptic terminals, and these receptors have been known to be activated by synaptically released glutamate and GABA which spill out from the synaptic clefts. However the relative contribution of these two receptors in modulating the excitability of mossy fiber axon was not reported so far. In this study, we revealed that glutamate spilled out from commissural/associational synapses evoked the facilitation of antidromic population spikes of mossy fibers. Increase in amplitude and decrease in latency of population spikes suggest that the number of recruited mossy fibers increases by depolarization of axonal membrane. Application of non‐NMDA receptor antagonist CNQX (10 μM) almost abolished this effect. TBOA (30 μM), an inhibitor of glutamate transporter, prolonged the duration of heterosynaptic facilitation. These results suggest that glutamate released from distant commissural/associational synapses spills out from synaptic cleft and activates the kainate receptors on the mossy fibers of CA3 region, and plays a major role in modulating presynaptic excitability than GABA. © 2010 Wiley Periodicals, Inc.
Nutritional reference values for Opuntia ficus‐indica determined by means of the boundary‐line approach
Authors: Blanco‐Macías Fidel , Magallanes‐Quintanar Rafael , Valdez‐Cepeda Ricardo D. , Vázquez‐Alvarado Rigoberto , Olivares‐Sáenz Emilio , Gutiérrez‐Ornelas Erasmo , Vidales‐Contreras Juan A. , Murillo‐Amador Bernardo 
Published: November 2010

AbstractOptimum concentrations and/or sufficiency ranges of nutrients are useful for a correct diagnosis and improvement of nutrient status of cultivated plants. To develop boundary‐line approach (BLA) standards for Opuntia ficus‐indica L., a database of N, P, K, Ca, and Mg concentrations in 1‐year‐old cladodes and cladodes fresh‐matter yield was used. The BLA optimum concentrations (associated with estimated maximum yield) for O. ficus‐indica were: N = 13.1 g kg–1, P = 3.2 g kg–1, K = 44.4 g kg–1, Ca = 38.1 g kg–1, and Mg = 17.3 g kg–1. The BLA sufficiency ranges at 95% yield were 8.4–20.3 g kg–1 for N, 2.4–4.2 g kg–1 for P, 38.2–50.8 g kg–1 K, 31.8–45.2 g kg–1 for Ca, and 14.3–20.9 g kg–1 for Mg. The BLA standards are comparable to those obtained in a previous study using compositional‐nutrient‐diagnosis (CND) approach.
Neotyphodium endophytes trigger salt resistance in tall and meadow fescues
Authors: Reza Sabzalian Mohammad , Mirlohi Aghafakhr 
Published: November 2010

AbstractInfection with Neotyphodium spp. endophytes increases resistance to drought stress and soil mineral imbalances in tall fescue (Festuca arundinacea Schreb. = Lolium arundinaceum (Schreb.) S. J. Darbysh.) and meadow fescue (Festuca pratensis Huds. = Lolium pratense (Huds.) Darbysh.). We hypothesized that resistance of these grasses to salinity stress may also be attributed to endophyte infection. Two tall fescue genotypes, Fa75 and Fa83, and one meadow fescue genotype, Fp60, infected (E+) with their endophytic fungi, Neotyphodium coenophialum (Glenn, Bacon and Hanlin) and N. uncinatum (Glenn, Bacon and Hanlin), respectively, and their noninfected counterparts (E–) were cultured in nutrient solution at three salinity levels of 0, 85, and 170 mM NaCl. Except for genotype Fa75, E+ plants exhibited higher leaf survival rates than E– clones at a high salinity level (170 mM). Root dry matter was higher in E+ than in E– plants, but shoot dry matter was not affected by endophyte infection. This resulted in a lower shoot‐to‐root ratio in E+ plants (1.63) compared with E– plants (2.40). Sodium (Na+) and chloride (Cl–) concentrations were greater in roots of E– than in E+ clones. In shoots, Na+ and Cl– concentrations were not affected by the endophyte. In contrast, E+ plants accumulated more potassium (K+), which resulted in a greater K+ : Na+ ratio in shoots of E+ than in those of E– plants. Our results show that endophyte infection reduced Na+ and Cl– concentrations in tall fescue and meadow fescue roots but increased K+ concentrations in the shoots. Based on these results, we conclude that endophyte‐infected grasses may thrive better in salinity‐stress environments.
Determination of the different components of cadmium short‐term uptake by roots
Authors: Redjala Tanegmart , Sterckeman Thibault , Louis Morel Jean 
Published: November 2010

AbstractAs the various components of the cadmium (Cd) root sink have not been clearly described, there is a need to precisely measure the respective contributions of apoplast and symplast to short‐term root Cd uptake and to explain the linear component of the absorption isotherms. A new method of fractionating Cd in roots was applied to two plant species with contrasting abilities to accumulate Cd: maize (Zea mays) and a Cd‐hyperaccumulating ecotype of alpine pennycress (Noccaea caerulescens). Their roots were exposed for 1 h to increasing concentrations of labeled Cd. Series of desorption baths were used to obtain the root apoplastic Cd in combination with a brief freezing step in liquid nitrogen to separate the intracellular metal from the apoplastic one. The apoplastic uptake accounted for 15% to 82% and for 48% to 96% of the total Cd uptake of maize and of alpine pennycress roots, respectively. In the case of maize, the concentration‐dependent symplastic net flux fitted a biphasic Michaelis‐Menten function, while in the case of alpine pennycress, a Michaelis‐Menten‐plus‐linear function proved a better fit. The second component of the symplastic net flux may reflect absorption through a low‐affinity transport system. Short‐term Cd uptake by roots is dominated by the high‐affinity transport system for exposure concentrations below 1 μM for maize and 0.2 μM for alpine pennycress, while cell‐wall binding prevailed for higher exposure concentrations.
Optically detunable, inductively coupled coil for self‐gating in small animal magnetic resonance imaging
Authors: Korn Matthias , Umathum Reiner , Schulz Jessica , Semmler Wolfhard , Bock Michael 
Published: November 2010

AbstractAn inductively coupled coil concept is presented, which improves the compensation of physiological motion by the self‐gating (SG) technique. The animal is positioned in a conventional volume coil encompassing the whole animal. A small, resonant surface coil (SG‐coil) is placed on the thorax so that its sensitive region includes the heart. Via inductive coupling the SG‐coil amplifies selectively the MR signal of the beating heart. With an optical detuning mechanism, this coupling can be switched off during acquisition of the MR image information, whereas it is active during SG data sampling to provide the physiological information. In vivo experiments on a mouse show an amplification of the SG signal by at least 40%. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
Mammalian target of rapamycin complex 1 is involved in differentiation of regenerating myofibers in vivo
Authors: Miyabara Elen H. , Conte Talita C. , Silva Meiricris T. , Baptista Igor L. , Bueno Carlos , Fiamoncini Jarlei , Lambertucci Rafael H. , Serra Carmen S. , Brum Patricia C. , Pithon‐curi Tania , Curi Rui , Aoki Marcelo S. , Oliveira Antonio C. , Moriscot Anselmo S. 
Published: November 2010

AbstractThis work was undertaken to provide further insight into the role of mammalian target of rapamycin complex 1 (mTORC1) in skeletal muscle regeneration, focusing on myofiber size recovery. Rats were treated or not with rapamycin, an mTORC1 inhibitor. Soleus muscles were then subjected to cryolesion and analyzed 1, 10, and 21 days later. A decrease in soleus myofiber cross‐section area on post‐cryolesion days 10 and 21 was accentuated by rapamycin, which was also effective in reducing protein synthesis in these freeze‐injured muscles. The incidence of proliferating satellite cells during regeneration was unaltered by rapamycin, although immunolabeling for neonatal myosin heavy chain (MHC) was weaker in cryolesion+rapamycin muscles than in cryolesion‐only muscles. In addition, the decline in tetanic contraction of freeze‐injured muscles was accentuated by rapamycin. This study indicates that mTORC1 plays a key role in the recovery of muscle mass and the differentiation of regenerating myofibers, independently of necrosis and satellite cell proliferation mechanisms. Muscle Nerve 42: 778–787, 2010
Synthesis of polyimides containing triphenylamine‐substituted triazole moieties for polymer memory applications
Authors: Wang Kun‐Li , Liu Yi‐Liang , Shih I‐Hao , Neoh Koon‐Gee , Kang En‐Tang 
Published: November 2010

AbstractA series of thermally stable aromatic polyimides containing triphenylamine‐substituted triazole moieties (AZTA‐PI)s were prepared and characterized. The glass transition temperatures (Tg) of the polyimides were found to be in the range of 262–314 °C. The polyimides obtained by chemical imidization had inherent viscosities of 0.25–0.44 dL g−1 in N‐methyl‐2‐pyrrolidinone. The number average molecular weights (Mn) and weight average molecular weights (Mw) were 1.9–3.2 × 104 and 3.2–5.6 × 104, respectively, and the polydispersity indices (PDI = Mw/Mn) were in the range of 1.70–1.78. A resistive switching device was constructed from the 4,4′‐hexafluoroisopropylidenediphthalic dianhydride‐based soluble polyimide (AZTA‐PIa) in a sandwich structure of indium‐tin oxide/polymer/Al. The as‐fabricated device can be switched from the initial low‐conductivity (OFF) state to the high‐conductivity (ON) state at a switching threshold voltage of 2.5 V under either positive or negative electrical sweep, with an ON/OFF state current ratio in the order of 105 at −1 V. The device is able to remain in the ON state even after turning off the power or under a reverse bias. The nonvolatile and nonrewritable natures of the ON state indicate that the device is a write‐once read‐many times (WORM) memory. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Synthesis of a novel graft copolymer with hyperbranched poly(glycerol) as core and “Y”‐shaped polystyrene‐b‐poly(ethylene oxide)2 as side chains
Authors: Pan Mugang , Wang Guowei , Zhang Yannan , Huang Junlian 
Published: November 2010

AbstractThe graft copolymers composed of “Y”‐shaped polystyrene‐b‐poly(ethylene oxide)2 (PS‐b‐PEO2) as side chains and hyperbranched poly(glycerol) (HPG) as core were synthesized by a combination of “click” chemistry and atom transfer radical polymerization (ATRP) via “graft from” and “graft onto” strategies. Firstly, macroinitiators HPG‐Br were obtained by esterification of hydroxyl groups on HPG with bromoisobutyryl bromide, and then by “graft from” strategy, graft copolymers HPG‐g‐(PS‐Br) were synthesized by ATRP of St and further HPG‐g‐(PS‐N3) were prepared by azidation with NaN3. Then, the precursors (Bz‐PEO)2‐alkyne with a single alkyne group at the junction point and an inert benzyl group at each end was synthesized by sequentially ring‐opening polymerization (ROP) of EO using 3‐[(1‐ethoxyethyl)‐ethoxyethyl]‐1,2‐propanediol (EEPD) and diphenylmethylpotassium (DPMK) as coinitiator, termination of living polymeric species by benzyl bromide, recovery of protected hydroxyl groups by HCl and modification by propargyl bromide. Finally, the “click” chemistry was conducted between HPG‐g‐(PS‐N3) and (Bz‐PEO)2‐alkyne in the presence of N,N,N′,N″,N”‐pentamethyl diethylenetriamine (PMDETA)/CuBr system by “graft onto” strategy, and the graft copolymers were characterized by SEC, 1H NMR and FTIR in details. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Easy synthesis and ring‐opening polymerization of 5‐Z‐amino‐δ‐valerolactone: New degradable amino‐functionalized (Co)polyesters
Authors: Blanquer Sebastien , Tailhades Julien , Darcos Vincent , Amblard Muriel , Martinez Jean , Nottelet Benjamin , Coudane Jean 
Published: November 2010

AbstractNovel 5‐Z‐amino‐δ‐valerolactone (5‐NHZ‐VL) was synthesized with an aim to prepare degradable polyesters and copolyesters having amino pendant groups. Following a straightforward and efficient synthetic pathway, 5‐NHZ‐VL was obtained in only two steps and up to 50% yield. The monomer was fully characterized by 1H NMR, 13C NMR, ESI mass spectrometry, and HPLC. Various conventional conditions were tested for this lactone ring‐opening polymerization and led to the novel corresponding poly(5‐NHZ‐VL) (Mn = 7000 g/mol; PD = 1.2). Following this homopolymerization, 5‐NHZ‐VL was copolymerized with ε‐caprolactone to generate a family of copolyesters with an amino‐group content ranging from 10 to 80%. Finally, the polyelectrolyte poly(5‐NH3+‐VL) was recovered by removal of the protecting group under acidic conditions, and integrity of the polyester backbone was confirmed by 1H NMR. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Metallocene supported on a polyhedral oligomeric silsesquioxane‐modified silica: Structural characterization and catalytic activity for ethylene polymerization
Authors: García‐Orozco Ivan , Velilla Teresa , Galland Griselda B. , dos Santos Joaõ Henrique Z. , Williams Roberto J.J. , Quijada Raúl 
Published: November 2010

AbstractPreliminary results on the activity of metallocene supported over a polyhedral oligomeric silsesquioxane (POSS)‐modified silica for ethylene polymerization (Bianchini et al., J Polym Sci Part A: Polym Chem 2005, 43, 5465–5476) were extended showing the effect of large variations of the amount of both POSS and metallocene on the catalyst activity. Diffuse reflectance infrared spectroscopy results showed that at low concentrations (<1 wt %), POSS was physically adsorbed on SiOH groups present in the silica surface through H‐bonds. At larger concentrations, POSS was adsorbed by covalent bonds with the silica surface. The metallocene catalyst was adsorbed either on the silica surface by interactions with residual SiOH groups or in the organic branches of the POSS. It was found that the highest contribution to the catalyst activity arose from the metallocene directly adsorbed on the silica support. The effect of POSS to increase the catalyst activity was mainly due to its effect as a horizontal spacer of metallocene molecules adsorbed on the silica surface. An optimum range of POSS and metallocene adsorbed on the silica support was found that gave catalyst activities close to the one of the homogeneous system while doubling the molar mass of the polyethylene produced. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
A novel way to numerically characterize DNA sequences and its application
Authors: Guo Ying , Wang Yan‐fang , Zhang Sheng‐li 
Published: November 2010

AbstractWe presented a novel way to numerically characterize DNA sequences based on the graphical representation for the sequences comparison and analysis. Instead of calculating the leading eigenvalues of the matrix for graphical representation, we computed curvature and torsion of curves as the descriptor to numerically characterize DNA sequences. The new method was tested on three data sets: the coding sequences of β‐globin gene, all of their exons, and 24 coronavirus geneomes from NCBI. The similarities/dissimilarities and phylogenetic tree of these species verify the validity of our method. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Clinical and biomechanical analyses to select a suture material for uvulopalatopharyngeal surgery
Authors: Huang Tsung‐Wei , Cheng Po‐Wen , Chan Yen‐Hui , Wang Chi‐Te , Fang Kai‐Min , Young Tai‐Horng 
Published: November 2010

OBJECTIVEThe selection of the degradation pattern of suture materials is critical in uvulopalatopharyngeal surgery because of the complex oral environment such as the constant presence of saliva; the microbial accumulation; and the functions related to speech, mastication, and swallowing. The aim of the study was to identify appropriate suture materials for uvulopalatopharyngeal surgery by analyzing the clinical and biomechanical results obtained using four different absorbable suture materials.STUDY DESIGNA randomized open‐label trial.SETTINGTertiary referral center.SUBJECTS AND METHODSEighty patients with obstructive sleep apnea syndrome who had undergone microdebrider‐assisted extended uvulopalatoplasty were randomized into the four suture groups: sutures of polyglycolide (Dexon) and copolymers of polyglycolide and other degradable polymers (Polysorb, Monocryl, Maxon). Handling characteristics, surgical outcomes, Young's modulus reduction, morphologic changes by scanning electron microscope, and saliva absorption test were analyzed.RESULTSMonocryl (poly(glycolide‐co‐∊‐caprolactone)) had the optimal handling characteristics and exhibited two‐stage degradation: sufficient tensile strength was maintained initially to allow wound healing, and then the suture degraded rapidly to avoid irritation. In contrast, the hydrolytic degradation of Dexon, Polysorb, and Maxon seemed to involve only an approximately single‐stage process in the oral environment. Moreover, a large amount of debris was observed among filaments in Dexon and Polysorb, whereas only some scattered debris accumulated on Monocryl and Maxon under scanning electron microscope.CONCLUSIONPoly(glycolide‐co‐∊‐caprolactone) has good handling characteristics and degrades in two stages. It is a suitable suture material for uvulopalatopharyngeal surgery.