bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrocatalytic and Analytical Response of Cobalt Phthalocyanine Modified Carbon Paste Electrodes Towards Antimalarial Endoperoxide Artemisinin
Authors: Debnath Chhanda , Saha Pijus , Ortner Astrid 
Published: February 2009

AbstractA cobalt phthalocyanine modified carbon paste electrode was constructed for the analysis of artemisinin in Artemisia annua plant. Artemisinin, a sesquiterpene endoperoxide, is a novel, important antimalarial drug and is used in the therapy against Plasmodium falciparum. The developed cobalt phthalocyanine modified electrode exhibited a significant electrocatalytic activity in presence of artemisinin when using cyclic and differential pulse voltammetry. Under optimized conditions in phosphate buffer of pH 7 a well defined voltammetric peak appeared at about −500 mV vs. Ag/AgCl. The differential pulse voltammetric peak current of artemisinin was increased linearly with the concentration range of 2.1×10−5 to 5.3×10−4 M (R=0.9997). The limit of detection (LOD) was found to be 6.5×10−6 M. The modified electrode was successfully tested for detecting artemisinin in complex plant materials.
Quantification of Binary and Ternary Mixtures of Homologous Nonylphenol Polyethoxylates Using the Potentiometric Sensor Array
Authors: Makarova Natalia Mikhailovna , Kulapina Elena Grigorevna 
Published: February 2009

AbstractThe electronic tongue system based on the potentiometric sensor array for the determination of nonionic surfactants was developed. Multivariate statistical analysis techniques as partial least squares (PLS) method and backpropagation artificial neural networks (ANN) were used for data processing. The proposed system was applied for the quantitative analysis of homologous polyoxyethylated nonylphenols in complex multicomponent model mixtures and natural water samples. The least relative errors of detection were obtained for artificial neural network. Proposed approach could be applied to further analyze of sewage waters and commercial technical samples.
Application of Multiway Chemometric Techniques for Analysis of AC Voltammetric Data
Authors: Jaworski Aleksander , Wikiel Hanna , Wikiel Kazimierz 
Published: February 2009

AbstractThree multiway calibration techniques have been applied for determining of the suppressor concentration in industrial copper electrometallization baths used in semiconductor manufacturing. Parallel factor analysis (PARAFAC) for multiway array decomposition coupled with inverse least squares (ILS) regression (PARAFAC/ILS), direct trilinear decomposition (DTLD) coupled with ILS (DTLD/ILS), and multilinear partial least squares (N‐PLS) regression were employed to develop and test calibration models based on trilinear AC voltammetric data. All techniques employed comparatively produce reliable calibration model and provide quantitative information about its robustness.
Molecularly Imprinted Polymer‐Based Sensors for Amperometric Determination of Nonelectroactive Substances
Authors: Pesavento Maria , D'Agostino Girolamo , Biesuz Raffaela , Alberti Giancarla 
Published: February 2009

AbstractAmperometric sensors for nonelectroactive substances have been obtained by contacting glassy carbon or graphite electrodes with molecularly imprinted polymeric (MIP) membranes, 300–0.6 μm thick. The thicker membranes were self standing membranes while the thinner ones were prepared by drop coating on a graphite electrode. Cyanuric acid and atrazine were the target compounds. Determinations were carried out at −850 mV (vs. Ag/AgCl(sat)) in aqueous solution at pH 1.5, followed by a step at +500. The current linearly depends on the concentration of the template molecule in aqueous solution up to 10−4 M. For atrazine the current increases with the concentration, while for cyanuric acid the current intensity decreases. Not any current variation was observed on bare carbon electrodes, nor on electrodes covered with a nonimprinted membrane. The detection limit was 9×10−7 M for atrazine and 2×10−5 M for cyanuric acid. The sensors response was very fast and selective for the corresponding template.
Determination of Bisulfites in Wines with an Electronic Tongue Based on Pulse Voltammetry
Authors: Labrador Roberto H. , Olsson John , Winquist Fredrik , Martínez‐Máñez Ramón , Soto Juan 
Published: February 2009

AbstractAn electronic tongue (ET) based on pulse voltammetry is used to predict concentrations of bisulfites in wine samples. The ET array consists of four working electrodes (gold, rhodium, platinum and stainless steel) encapsulated into a stainless steel cylinder used at the same time as both the body of the ET system and the pseudoreference/counter electrode. The ET device is additionally equipped with a self‐polishing system. Multivariate analysis including Cross validation and partial least square (PLS) techniques are applied for data management and prediction models building. Ascorbic acid and histamine have also been included in the predictive analysis.
Determination of Trace of Cobalt in Complex Matrices by Adsorptive Stripping Voltammetry at a Lead Film Electrode
Authors: Tyszczuk Katarzyna , Rutyna Iwona , Korolczuk Mieczyslaw 
Published: February 2009

AbstractAn adsorptive stripping voltammetric procedure for the determination of cobalt in a complex matrices at an in situ plated lead film electrode was described. The procedure exploits the enhancement effect of a cobalt peak observed in the system Co(II)–nioxime–piperazine‐1,4‐bis(2‐ethanesulfonic acid)–cetyltrimethylammonium bromide. The calibration graph was linear from 5×10−10 to 2×10−8 mol L−1 and from 1×10−10 to 1×10−9 mol L−1 for the accumulation times 120 and 600 s, respectively. The detection limit (based on the 3 σ criterion) for Co(II) following accumulation time of 600 s was 1.1×10−11 mol L−1. The interference of high concentrations of foreign ions and surfactants was studied.
Electrochemical Behavior of o‐Nitrophenol at Hexagonal Mesoporous Silica Modified Carbon Paste Electrodes
Authors: Zhou Changli , Liu Zhen , Dong Yanmin , Li Dongmei 
Published: February 2009

AbstractA hexagonal mesoporous silica (HMS) modified carbon paste electrode (CPE) was fabricated and characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods (ferrocene as a probe). The electrochemical behavior of nitrophenol (o‐NP) at the HMS modified electrode (HMSCPE) was investigated. Compared with CPE, a well‐defined reduction peak and a remarkably peak current response was observed. It is indicated that mesoporous HMS exhibited remarkable enhancement effects on the electrochemical reduction of o‐NP. The electrochemical reduction mechanism was also discussed. Consequently, a simple and sensitive electrochemical method was proposed for the determination of o‐NP, which was used to determine o‐NP in waste water samples.
Safety evaluation of sewage‐sludge‐derived fuels by comparison with other fuels
Authors: Li Xin‐Rui , Lim Woo‐Sub , Iwata Yusaku , Koseki Hiroshi 
Published: February 2009

AbstractThe utility of sewage sludge as a biomass fuel is taken as a new approach to recycle unwanted wastes as renewable energy and deal with global warming. However, safety caring of this new type of fuel is a premise before it is practically used in boilers. Thermal behaviors of four sludge‐derived fuels which are under development were examined by several calorimeters (such as thermogravimetry/differential thermal analysis, C80 and thermal activity monitor) at temperature ramp and isothermal conditions. Heat generation at relatively low temperatures was observed. The corresponding spontaneous ignition was detected in an adiabatic spontaneous ignition tester at 80∘C in some sludge species. Moreover, a certain amount of gaseous evolution was accompanied when the sludge fuels were stored at room temperature and at 60∘C. Oxidation is mainly responsible for the heat and gas release from the sludge fuels. The hazards of the sewage sludge fuels were also compared with a bituminous coal and a refuse‐derived fuel, which have the main feature of spontaneous ignition. Copyright © 2009 John Wiley & Sons, Ltd.
Removal of second branchial cleft cysts using a retroauricular approach
Authors: Chen Wei‐Liang , Fang Si‐Lian 
Published: February 2009

AbstractBackgroundSecond branchial cleft cysts (also called cervical lymphoepithelial cysts) usually present in adulthood, and cosmesis of surgical access is an important issue. This study was performed to assess the feasibility and outcome of a retroauricular approach for removing second branchial cleft cysts.MethodsEight patients underwent removal of second branchial cleft cysts using a retroauricular approach.ResultsAll 8 second branchial cleft cysts were removed successfully, and the wounds healed uneventfully. None of the patients suffered from weakness of the great auricular nerve. Marginal nerve palsy did not occur postsurgery. Average follow‐up period was 14.5 months (range, 6–20 months) with no tumor recurrence. The incision scars were invisible.ConclusionSecond branchial cleft cyst resection using a retroauricular approach is a feasible method that provides an acceptable cosmetic outcome. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Playing a brass instrument after total laryngectomy: A case report
Authors: Cavalot Andrea Luigi , Schindler Antonio , Juliani Elsa , Schindler Oskar , Cortesina Giorgio 
Published: February 2009

AbstractBackgroundA brass instrument is a musical instrument in which the tone is produced by vibration of the lips as the player blows into a tubular resonator. The case of a professional brass player who continued his activity after total laryngectomy, with insertion of a voice prosthesis in a tracheoesophageal shunt, is reported.MethodsA videoendoscopic and videofluoroscopic study of the patient during brass playing was conducted.ResultsA nonvibrating, open neoglottis during brass playing was found on videoendoscopy. Videofluorography revealed an enlarged hypopharynx, a thick neoglottis while playing at lower tone; at higher pitch the tongue base was retracted, the neoglottis was thin and stretched, and the subneoglottic area was extremely enlarged.ConclusionThe case reported shows that the insertion of a voice prosthesis in a tracheoesophageal shunt seems to create a regulating airflow system sufficiently advanced to play a brass instrument, further reducing the disability of laryngeal speakers. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Retropharyngeal nodal metastasis related to higher rate of distant metastasis in patients with N0 and N1 nasopharyngeal cancer
Authors: Tham Ivan Weng‐Keong , Hee Siew Wan , Yap Swee Peng , Tuan Jeffrey Kit‐Loong , Wee Joseph 
Published: February 2009

AbstractBackgroundRetropharyngeal lymph node (RLN) staging in nasopharyngeal carcinoma (NPC) can be controversial.MethodsWe retrospectively reviewed all patients with T2–4, N0–1 NPC treated between 1992 and 1994 to examine if RLN metastasis resulted in an increased incidence of distant metastases.ResultsOf the 667 patients with NPC, 395 had T2–4, N0–1 disease, 140 had N0, and 255 had N1. All had staging CT scans and were treated with radiotherapy. Median follow‐up was 8.3 years. Seventy‐four percent showed undifferentiated histology. In this cohort, 187 (47%) had RLN metastases. Multivariate analysis showed that RLN conferred a higher hazard for distant metastasis (p = .04). Using the Kaplan–Meier method, patients with N0 disease and RLN had a similar hazard for distant metastases as patients with N1 disease when compared with patients with N0 disease and without RLN.ConclusionPatients with N0 disease and RLN appear to share a similar prognosis to patients with N1 disease. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Stability of dimeric interface in banana lectin: Insight from molecular dynamics simulations
Authors: Gupta Garima , Vishveshwara Saraswathi , Surolia Avadhesha 
Published: February 2009

AbstractBanana lectin (Banlec) is a homodimeric non‐glycosylated protein. It exhibits the β‐prism I structure. High‐temperature molecular dynamics simulations have been utilized to monitor and understand early stages of thermally induced unfolding of Banlec. The present study elucidates the behavior of the dimeric protein at four different temperatures and compares the structural and conformational changes to that of the minimized crystal structure. The process of unfolding was monitored by following the radius of gyration, the rms deviation of each residue, change in relative solvent accessibility and the pattern of inter‐ and intra‐subunit interactions. The overall study demonstrates that the Banlec dimer is a highly stable structure, and the stability is mostly contributed by interfacial interactions. It maintains its overall conformation during high‐temperature (400–500 K) simulations, with only the unstructured loop regions acquiring greater momentum under such condition. Nevertheless, at still higher temperatures (600 K) the tertiary structure is gradually lost which later extends to loss of secondary structural elements. The pattern of hydrogen bonding within the subunit and at the interface across different stages has been analyzed and has provided rationale for its intrinsic high stability. © 2009 IUBMB IUBMB Life 61(3): 252–260, 2009
Spiral and square microstructured surfaces: The effect of the decreasing size of photo‐immobilized hyaluronan domains on cell growth
Authors: Di Canio Clara , Lamponi Stefania , Barbucci Rolando 
Published: February 2009

AbstractSpiral and squared micropatterned surfaces of decreasing dimensions were realized by photo‐immobilizing a photoreactive hyaluronan (Hyal) derivative on silanized glass substrates. The microstructured surfaces were observed by atomic force microscope and scanning electron microscope. Scanning electron microscope analysis revealed the presence of a spiral (ranging from 100 μm down to 1 μm in the central part) and a square pattern consisting of a central square of 100 μm × 100 μm and squares of different dimensions decreasing from the centre to the edges of the micropatterned area (2 μm × 1 μm). Three cell types were tested on all the microstructured surfaces: human coronary artery endothelial cells (HCAEC), human dermal fibroblasts (C54), and NIH 3T3 fibroblasts. Cell adhesion analysis demonstrated that HCAEC and C54 did not adhere to the immobilized Hyal on silanized glass but adapted their shape to the different sizes of the square and spiral patterns. Also, in both geometric patterns, the reduction of the adhesive glass width induced C54 to create bonds amongst themselves. NIH 3T3 cells adhered inside the squares and the spiral but reducing the adhesive glass width induced NIH 3T3 to adhere to immobilized Hyal. This fact is explained by the interactions between the cells and the immobilized Hyal as a consequence of the CD44/Hyal binding. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Exogenous crosslinking recovers the functional integrity of intervertebral disc secondary to a stab injury
Authors: Chuang Shih‐Youeng , Lin Leou‐Chyr , Tsai Yi‐Chian , Wang Jaw‐Lin 
Published: February 2009

AbstractExogenous crosslinking was proved to improve the fatigue resistance of anulus fibrosus and the stability of motion segment. The effect of crosslinking on the recovery of stab‐injured discs, however, was less studied. The purpose of this study is to find if the exogenous crosslinking can increase the mechanical function of injured discs. Fresh healthy porcine discs (T2/T9) from 6‐month‐old swine were obtained immediately following death. Anular puncture using 16 and 18 G spinal needle were used to create medium and large disc stab injury models. Three treatments were designed for each injury model. The first one is the injured discs without treatment. The second one is the injured discs soaked with phosphate buffered solution for 2 days. The third one is the injured discs soaked with 0.33% genipin solution for 2 days. The disc integrity was evaluated using quantitative discomanometry (QD) apparatus. Four QD parameters, that is, the leakage pressure and volume, and the saturate pressure and volume, were analyzed to find the efficacy of treatment. We found that soaking of genipin solution recovered the disc leakage pressure from 1.3 to 1.8 MPa in 16 G‐injury‐model and from 2.3 to 3.2 MPa in 18 G‐injury‐model, and recovered the saturate pressure from 1.6 to 2.0 MPa in 16 G‐injury‐model and from 2.7 to 3.7 MPa in 18 G‐injury‐model. The improvement of disc integrity by soaking with genipin solution indicate that the exogenous crosslinking may help the biomechanical performance of an injured disc. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Surface modification of PCL‐TCP scaffolds improve interfacial mechanical interlock and enhance early bone formation: An in vitro and in vivo characterization
Authors: Yeo A. , Wong W. J. , Khoo H. H. , Teoh S. H. 
Published: February 2009

AbstractPretreatment of polycaprolactone‐20% tricalcium phosphate (PCL‐TCP) scaffolds under alkaline conditions can be utilized to alter surface characteristics for enhanced early bone formation. PCL‐TCP scaffolds were treated with sodium hydroxide (NaOH) at various time intervals (group A: untreated, group B: 3M NaOH for 48 h, and group C: 3M NaOH for 96 h). In vitro results showed a greater degree of physical changes in the NaOH‐treated scaffolds (B and C) than the untreated group (A). Clearly, the NaOH‐treated scaffolds showed an increased surface roughness than the untreated ones. A significantly large number of “channel‐like” pits and greater average pit sizes were detected in groups B (14.51 ± 10.9 μm) and C (20.27 ± 14.3 μm); and absent in group A. In addition, treated scaffolds had a significant reduction of the water contact angle (40.9–58.2%). Favorably, the pore dimensions and scaffold rod thickness remained unchanged throughout the experiment. When implanted in the calvaria of rabbits, NaOH‐treated scaffolds reported greater early matrix deposition and bone formation from scanning electron images and Micro‐computed tomography analyses. In conclusion, pretreatment of PCL‐TCP scaffolds with NaOH increases the wettability and surface area for initial matrix deposition and early bone ingrowth. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Glycolic acid modulates the mechanical property and degradation of poly(glycerol, sebacate, glycolic acid)
Authors: Sun Zhi‐Jie , Wu Lan , Huang Wei , Chen Chang , Chen Yan , Lu Xi‐Li , Zhang Xiao‐Lan , Yang Bao‐Feng , Dong De‐Li 
Published: February 2009

AbstractThe development of biodegradable materials with controllable degradation properties is beneficial for a variety of applications. Poly(glycerol‐sebacate) (PGS) is a promising candidate of biomaterials; so we synthesize a series of poly(glycerol, sebacate, glycolic acid) (PGSG) with 1:2:0, 1:2:0.2, 1:2:0.4, 1:2:0.6, 1:2:1 mole ratio of glycerol, sebacate, and glycolic acid to elucidate the relation of doped glycolic acid to the degradation rate and mechanical properties. The microstructures of the polymers with different doping of glycolic acid were dissimilar. PGSG with glycolic acid in the ratio of 0.2 displayed an integral degree of ordering, different to those with glycolic acid in the ratio of 0, 0.4, 0.6, and 1, which showed mild phase separation structure. The number, ΔHm, and temperature of the PGSG melting peaks tended to decrease with the increasing ratio of doped glycolic acid. In vitro and in vivo degradation tests showed that the degradation rate of PGSG with glycolic acid in the ratio of 0.2 was slowest, but in the ratio range of 0, 0.4, and 0.6, the degradation rate increased with the increase of glycolic acid. All PGSG samples displayed good tissue response and anticoagulant effects. Our data suggest that doping glycolic acid can modulate the microstructure and degree of crosslinking of PGS, thereby control the degradation rate of PGS. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Characterization of the spatial immobilization manner of poly(ethylene glycol) to a titanium surface with immersion and electrodeposition and its effects on platelet adhesion
Authors: Tanaka Yuta , Matsuo Yuh , Komiya Takayuki , Tsutsumi Yusuke , Doi Hisashi , Yoneyama Takayuki , Hanawa Takao 
Published: February 2009

AbstractBoth terminals of a poly(ethylene glycol) (PEG) molecule were terminated with amines. The PEG was electrodeposited onto titanium (Ti) to give it the biofunctions such as blood compatibility. The effects of the amine of PEG terminals and the pH at PEG solution on the adsorption amount of PEG molecules and the thickness of PEG layer immobilized on the Ti surface were evaluated using quartz crystal microbalance technique and X‐ray photoelectron spectroscopy. The interfacial reactivity between PEG terminals and the Ti surface was the largest at pH 11, according to the interaction between the charge of terminal amines of PEG and the point of zero charge of Ti oxide. The orientations of PEG molecules immobilized on the Ti surface with immersion or electrodeposition at pH 11 were determined by Fourier transform infrared reflection absorption spectroscopy. Consequently, the terminal amines of PEG were oriented perpendicularly to the surface in electrodeposition rather than in immersion. The charged PEG randomly immobilized on the Ti surface with immersion led to platelet aggregation, whereas U‐shaped PEG molecule immobilized with electrodeposition inhibited platelet adhesion and aggregation. The immobilization manners of PEG on the Ti surface were strongly associated with a biofunction such as platelet adhesion. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
The pore size of polycaprolactone scaffolds has limited influence on bone regeneration in an in vivo model
Authors: Roosa Sara M. Mantila , Kemppainen Jessica M. , Moffitt Erin N. , Krebsbach Paul H. , Hollister Scott J. 
Published: February 2009

AbstractBone tissue engineering scaffolds should be designed to optimize mass transport, cell migration, and mechanical integrity to facilitate and enhance new bone growth. Although many scaffold parameters could be modified to fulfill these requirements, pore size is an important scaffold characteristic that can be rigorously controlled with indirect solid freeform fabrication. We explored the effect of pore size on bone regeneration and scaffold mechanical properties using polycaprolactone (PCL) scaffolds designed with interconnected, cylindrical orthogonal pores. Three scaffold designs with unique microarchitectures were fabricated, having pore sizes of 350, 550, or 800 μm. Bone morphogenetic protein‐7 transduced human gingival fibroblasts were suspended in fibrin gel, seeded into scaffolds, and implanted subcutaneously in immuno‐compromised mice for 4 or 8 weeks. We found that (1) modulus and peak stress of the scaffold/bone constructs depended on pore size and porosity at 4 weeks but not at 8 weeks, (2) bone growth inside pores depended on pore size at 4 weeks but not at 8 weeks, and (3) the length of implantation time had a limited effect on scaffold/bone construct properties. In conclusion, pore sizes between 350 and 800 μm play a limited role in bone regeneration in this tissue engineering model. Therefore, it may be advantageous to explore the effects of other scaffold structural properties, such as pore shape, pore interconnectivity, or scaffold permeability, on bone regeneration when designing PCL scaffolds for bone tissue engineering. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010