bluuebunny/crossref_metadata_2025 huggingface dataset:
Acetylenchemie 12. Mitt.: Weitere studien über die phasentransfer‐katalysierte umsetzung des 9(10H)‐acridinons mil alkinylhalogeniden
Authors: Reisch Johannes , Salehi‐Artimani Reza A.
Published: May 2010

Bei der phasentransfer‐katalysierten Umsetzung von 9(10H)‐Acridinon mil 1‐Brom‐2‐propin entsteht 10‐(2‐Propinyl)‐9(10H)‐acridinon. Aus diesem bilden sich via Prototropie 10‐(1,2‐Propadienyl)‐9(10H) acridinon und 10‐(1‐Propinyl)‐9(10H)‐acridinon. Unter den genannten Bedingungen führt 1‐Brom‐2‐butin zu 10‐(2‐Butinyl)‐9(10H)‐acridinon, 2‐Chlor‐3‐butin zu 10‐(l‐Methyl‐1,2‐propadienyl)‐9(10H)‐acridinon, 10‐(1‐Methyl‐2‐propinyl)‐9(10H)‐acridinon, 9‐(1‐Methyl‐2‐propinyloxy)‐acridin und 10‐[1‐Methyl‐3‐(3,4‐di‐methylphenyl‐2‐propinyl)]‐9(10H)‐acridinon. Die Entstehungsweise der Produkte wird experimentell abgesichert und mit früheren Befunden verglichen.
The reactions of C‐methylheterocycles with thionyl chloride. Part 3. The transformation of some five‐and six‐membered heterocycles
Authors: Al‐Shaar Adnan H. M. , Gilmour David W. , Lythgoe David J. , Mcclenaghan Ian , Ramsden Christopher A.
Published: May 2010

Reactions of various five‐and six‐membered C‐methylheterocycles with hot thionyl chloride gave chlorothio intermediates which were not characterized but which gave 1,2,4‐thiadiazole derivatives when reacted with amidines and gave thioamides when reacted with amines. When 2,3‐dimethyl‐6‐ethoxycarbonylimidazo‐[4,5‐b]pyridine (26) was treated with thionyl chloride a trisulphane 27 was isolated.
10th international symposium on the synthesis and applications of isotopes and isotopically labelled compounds—applications of isotopes in agriculture, nutrition and environmental research Session 11, Wednesday, June 17, 2009
Authors: McKillican Bruce , White Franklin
Published: May 2010

The preparation of carbon‐14 labeled compounds and their use in discovery and development of agrochemicals was discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Characterization of conformational changes and noncovalent complexes of myoglobin by electrospray ionization mass spectrometry, circular dichroism and fluorescence spectroscopy
Authors: Lin Xin , Zhao Wenjie , Wang Xian
Published: May 2010

Electrospray ionization mass spectrometry (ESI‐MS) was employed to monitor the heme release and the conformational changes of myoglobin (Mb) under different solvent conditions, and to observe ligand bindings of Mb. ESI‐MS, complemented by circular dichroism and fluorescence spectroscopy, was used to study the mechanism of acid‐ and organic solvent‐induced denaturation by probing the changes in the secondary and the tertiary structure of Mb. The results obtained show that complete disruption of the heme–protein interactions occurs when Mb is subjected to one of the following solution conditions: pH 3.2–3.6, or solution containing 20–30% acetonitrile or 40–50% methanol. Outside these ranges, Mb is present entirely in its native state (binding with a heme group) or as apomyoglobin (i.e. without the heme). Spectroscopic data demonstrate that the denaturation mechanism of Mb induced by acid may be significantly different from that by the organic solvent. Low pH reduces helices in Mb, whereas certain organic content level in solution results in the loss of the tertiary structure. ESI‐MS conditions were established to observe the H2O‐ and CO‐bound Mb complexes, respectively. H2O binding to metmyoglobin (17 585 Da), where the heme iron is in the ferric oxidation state, is observed in ESI‐MS. CO binding to Mb (17 595 Da), on the other hand, can be only observed after the heme iron is reduced to the ferrous form. Therefore, ESI‐MS combined with spectroscopic techniques provides a useful means for probing the formation of ligand‐binding complexes and characterizing protein conformational changes. Copyright © 2010 John Wiley & Sons, Ltd.
Interspecies comparison of mucosal wave properties using high‐speed digital imaging
Authors: Regner Michael F. , Robitaille Mark J. , Jiang Jack J.
Published: May 2010

Objectives/Hypothesis:

The purpose of this study was to compare the vocal fold vibratory characteristics of ex vivo bovine, canine, ovine, and porcine larynges to human male and female vocal fold vibrations to determine the best model organism for laryngeal studies concerning vibratory and kinetic characteristics.

Study Design:

Prospective experimental.

Methods:

High‐speed videos of phonation were gathered at 4,000 frames per second (fps) in the animal models and human high‐speed endoscopy data were gathered at 2,000 fps. Videos were converted into kymograms, and the amplitude, oscillation frequency, and phase difference of vocal fold vibration were measured.

Results:

No statistically significant differences were found with respect to frequency, amplitude, or phase difference between canines and humans. Porcines were not significantly different from human females but did have an oscillation frequency significantly different from human males. Ovine vibrational amplitudes were significantly different from humans, and bovine frequency and amplitude differed significantly from humans.

Conclusions:

Canine and porcine larynges are the most appropriate model specimens for laryngeal studies contingent on vibratory or kinetic properties of phonation.
Comparison of salvage and planned pharyngolaryngectomy with jejunal transfer for hypopharyngeal carcinoma after chemoradiotherapy
Authors: Kadota Hideki , Fukushima Junichi , Nakashima Torahiko , Kumamoto Yoshihiko , Yoshida Sei , Yasumatsu Ryuji , Shiratsuchi Hideki , Morita Masaru , Komume Shizuo
Published: May 2010

Objectives/Hypothesis:

Salvage surgery after definitive chemoradiotherapy is often associated with a higher rate of perioperative complications and poor prognosis. The objective of this study is to examine the safety and efficacy of free jejunal transfer after salvage pharyngolaryngectomy for patients with locally recurrent hypopharyngeal carcinoma after definitive chemoradiotherapy.

Study Design:

A retrospective analysis of patients with advanced hypopharyngeal carcinoma who underwent pharyngolaryngectomy and reconstruction using free jejunum.

Methods:

Forty patients who underwent pharyngolaryngectomy with jejunal transfer were included in this study. Fourteen patients underwent surgery after definitive chemoradiotherapy (the salvage‐surgery group), whereas 26 patients underwent surgery after planned preoperative chemoradiotherapy (the planned‐surgery group). The perioperative conditions, mortality, morbidity, functional outcomes, and oncologic outcomes in each group were compared.

Results:

The patients in the salvage‐surgery group lost an average of 9 kg in weight before surgery, which thus indicated a malnourished condition. However, the incidence of all perioperative complications did not differ significantly between the groups. All patients in both groups achieved oral intake without tube feeding, and the intervals to start oral intake were 12.8 days in the salvage‐surgery group and 15.6 days in the planned‐surgery group, which was not significantly different. The 5‐year disease‐free survival was 57.1% in the salvage‐surgery group and 50.4% in the planned‐surgery group, which was not significantly different.

Conclusions:

Salvage pharyngolaryngectomy and jejunal transfer can be performed safely and reliably for patients with locally recurrent hypopharyngeal carcinoma, and it is an excellent option after a failure of definitive chemoradiotherapy.
Cut‐off value for needle washout thyroglobulin in athyrotropic patients
Authors: Lee Young Hen , Seo Hyung Suk , Suh Sang‐il , Lee Nam Joon , Kim Jung Hyuk , Seol Hae Young , Lee Ju‐Han , Kwon Soon‐Young , Kim Nan Hee , Seo Ji A. , Yang Kyung‐Sook
Published: May 2010

Objectives/Hypothesis:

The purpose of this study was to determine the appropriate cut‐off value for fine needle aspiration‐thyroglobulin (FNA‐Tg) associated with postoperative recurrences and validate the diagnostic efficacy of FNA‐Tg in patients after total thyroidectomy compared with concomitant cytology (C).

Study Design:

Retrospective.

Methods:

We retrospectively evaluated the results of ultrasound‐guided FNAs performed for suspicious cervical lesions of 40 patients (male:female = 10:30; mean age, 44.0 years) after total thyroidectomy (mean duration, 89.1 months), to acquire the material for Tg and C analysis. After collection of the cytologic sample, we rinsed the same needle with 1 mL of normal saline for Tg radioimmunoassay.

Results:

Of 40 lesions (mean size, 0.89 cm; range, 0.3–3.5cm), 21 were confirmed as recurrences and 19 were nonrecurrences. The rates of nondiagnostic sampling and sensitivity and specificity of FNA‐C when diagnostic sampling was obtained were 40% (16/40), 100% (14/14), and 90.0% (9/10), respectively. According to receiver operating characteristic analysis, the optimal cut‐off value of FNA‐Tg was 4.1 ng/mL (sensitivity, 100% [21/21]; specificity, 100% [19/19], P < .05). Furthermore, in 16 inconclusive lesions due to nondiagnostic cytologic results, the FNA‐Tg results coincided with a final diagnosis (seven recurrences and nine nonrecurrences). The cases with maximum diameters <1 cm showed a significantly increased rate of nondiagnostic cytologic results, and the FNA‐Tg results were more helpful than lesions ≥1 cm in diagnosing a recurrence (P < .05).

Conclusions:

Measurement of FNA‐Tg is helpful for distinguishing recurrent from nonrecurrent lesions in the majority of patients who were previously treated for well‐differentiated papillary thyroid carcinoma.
Is the width of the labyrinthine portion of the fallopian tube implicated in the pathophysiology of Bell's palsy?: A prospective clinical study using computed tomography
Authors: Kefalidis Georgios , Riga Maria , Argyropoulou Paraskevi , Katotomichelakis Michael , Gouveris Charalampos , Prassopoulos Panos , Danielides Vasilios
Published: May 2010

Objectives/Hypothesis:

The pathogenetic mechanisms underlying Bell's palsy remain obscure, despite the extensive relevant research. Magnetic resonance imaging (MRI) studies have strongly indicated that facial nerve edema cannot be regarded as the sole etiologic factor, because it might persist long after full clinical recovery, or might be demonstrated in the clinically unaffected side or healthy controls. The aim of this study was to investigate the hypothesis that a narrow facial canal might be implicated in the pathophysiology of Bell's palsy.

Study Design:

Prospective clinical study.

Methods:

A high‐resolution computerized tomography of the temporal bone with 1‐mm thick contiguous axial sections was performed in 25 patients with unilateral Bell's palsy. The width of the fallopian tube was measured at the meatal foramen and the middle part of its labyrinthine segment.

Results:

When using paired Student t tests, the measured width of the affected ear was found significantly smaller than that of the unaffected side, both at the meatal foramen (P = .007) and at the middle part of the labyrinthine segment (P = .03).

Conclusions:

Bell's palsy seems to usually coincide with the narrower fallopian tube of the patient. This anatomical detail, supported by previous MRI studies, seems to indicate that an asymmetry between the right and left fallopian tube might be a necessary pathogenetic mechanism for the development of a facial nerve edema into Bell's palsy in the narrower fallopian canal. More studies on large healthy populations are needed before a notable facial canal asymmetry is linked to a higher risk for developing Bell's palsy.
Neck and shoulder disability following reconstruction with the pectoralis major pedicled flap
Authors: Moukarbel Roger V. , Fung Kevin , Franklin Jason H. , Leung, Andrew , Rastogi Ravi , Anderson Cathy M. , Yoo John H.
Published: May 2010

Objectives/Hypothesis:

To conduct a comprehensive assessment of shoulder and neck function following the pectoralis major pedicled flap (PMPF) for head and neck reconstruction.

Design:

Case‐control study.

Methods:

The study group consisted of laryngectomized patients who underwent PMPF and a control group of those who underwent standard laryngectomy. Bilateral quantitative measurements of shoulder strength and range of motion (ROM) and neck ROM by a blinded physiotherapist and subjective quality‐of‐life assessment using the Shoulder Pain and Disability Index (SPADI) and Neck Disability Index (NDI) questionnaires were collected. Lateral cervical radiographs in the neutral, flexion, and extension positions were evaluated by a blinded neuroradiologist. The main outcome measures were shoulder ROM, strength, and SPADI scores; physical and radiologic measurements of neck ROM; and NDI Score.

Results:

Shoulder analysis showed a significantly reduced flexion angle (P = .043) and combined internal/external rotation angle on the operated side (P = .027) and a significant strength reduction for the flexion, external rotation, and adduction domains (P < .05). SPADI score analysis showed a significantly higher disability score (P = .017) and total score (P = .009) on the PMPF side. Neck physical analysis showed significant differences in extension (P = .013) and total ROM distances (P = .002) but not flexion (P = .184). The total flexion/extension angular ROM was reduced in the PMPF population (P = .05) due to a reduced neck extension excursion angle from a neutral position (P = .04).

Conclusions:

The PMPF for head and neck reconstruction is associated with a limitation in neck ROM attributed to a loss in extension and reduced shoulder strength and ROM.
Organ preservation surgery for laryngeal squamous cell carcinoma: Low incidence of thyroid cartilage invasion
Authors: Hartl Dana M. , Landry Guillaume , Hans Stéphane , Marandas Patrick , Brasnu Daniel F.
Published: May 2010

Objectives/Hypothesis:

Determine the incidence and risk factors for thyroid cartilage invasion in early and midstage laryngeal cancer.

Study Design:

Retrospective review.

Methods:

A retrospective review was carried out of tumors treated by open surgery with at least partial resection of thyroid cartilage from 1992 to 2008. Preoperative laser, radiation therapy, or chemotherapy were excluded. Tumor stage, anterior commissure involvement, vocal fold (VF) mobility, computed tomography (CT) scan, and pathological cartilage status were recorded.

Results:

Three hundred fifty‐eight patients were treated for tumors staged cT1 (32%), cT2 (53%), and cT3 (15%) by vertical (26%), supracricoid (62%), or supraglottic partial laryngectomy (12%). The thyroid cartilage was invaded in 8.9% of cases. Abnormal VF mobility was significantly related to thyroid cartilage invasion (Fisher exact test, P = .0002). Neither anterior commissure involvement nor CT scan were related to cartilage invasion.

Conclusions:

Thyroid cartilage invasion was rare but increased if VF mobility was impaired. This has implications for transoral resection, which unlike open surgery avoids unnecessary cartilage resection.
A novel inner ear monitoring system for evaluating ototoxicity of gentamicin eardrops in guinea pigs
Authors: Yang Ting‐Hua , Liu Shing‐Hwa , Young Yi‐Ho
Published: May 2010

Objective/Hypothesis:

Although most studies have identified damage in the cochlea and semicircular canals as the primary sites of aminoglycoside toxicity, little attention has been devoted to the toxic effects on the otolithic organs. This study aimed to assess the toxic effect of gentamicin eardrops on the inner ear end organs via a novel inner ear monitoring system combined with morphological examination.

Study Design:

Prospective study.

Methods:

Guinea pigs were treated with 50 μL saline (n = 10) and 50 μL gentamicin (40 mg/mL; n = 10) on the right and left round window membranes, respectively. An inner ear monitoring system, including auditory brainstem response (ABR), caloric, ocular vestibular‐evoked myogenic potential (oVEMP), and cervical VEMP (cVEMP) tests, was used to assess ototoxicity in guinea pigs at 2 weeks after treatment. The animals were then sacrificed for morphological study via confocal microscopy.

Results:

Normal results in ABR, caloric, cVEMP, and oVEMP tests were shown in all saline‐treated ears, whereas elevated ABR threshold and absent responses in caloric, oVEMP, and cVEMP tests were noted in all gentamicin‐treated ears. The cochlear and vestibular explants harvested from the gentamicin‐treated ears revealed substantial loss of hair cells.

Conclusions:

The inner ear monitoring system, including ABR, caloric, oVEMP, and cVEMP tests, might help to evaluate toxicity information of the topical eardrops or agents on the inner ear end organs, including cochlea, semicircular canals, utricle, and saccule.
Multiple and sign‐changing solutions for the multivalued p ‐Laplacian equation
Authors: Carl Siegfried , Motreanu Dumitru
Published: May 2010

We consider a class of elliptic inclusions under Dirichlet boundary conditions involving multifunctions of Clarke's generalized gradient. Under conditions given in terms of the first eigenvalue as well as the Fučik spectrum of the p ‐Laplacian we prove the existence of a positive, a negative and a sign‐changing solution. Our approach is based on variational methods for nonsmooth functionals (nonsmooth critical point theory, second deformation lemma), and comparison principles for multivalued elliptic problems. In particular, the existence of extremal constant‐sign solutions plays a key role in the proof of sign‐changing solutions (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flavan‐3‐ol C‐glycosides – Preparation and model experiments mimicking their human intestinal transit
Authors: Hasslauer Iris , Oehme Anett , Locher Sanja , Valotis Anagnostis , van't Slot Gordon , Humpf Hans‐Ulrich , Schreier Peter
Published: May 2010

In order to study the human intestinal transit of flavan‐3‐ol C‐glycosides, several C‐glycosyl derivatives were prepared by non‐enzymatic reaction of (+)‐catechin with α‐D‐glucose, α‐D‐galactose and α‐D‐rhamnose, respectively. In contrast to literature data, we propose that the reaction mechanism proceeds in analogy to the rearrangement of flavan‐3‐ols during epimerization under alkaline conditions. Four of the 12 synthesized flavan‐3‐ol C‐glycosides were incubated under aerobic conditions at 37°C using saliva (2 min) and simulated gastric juice (3 h). To simulate human intestine, the C‐glycosides were also incubated under anaerobic conditions at 37°C both in human ileostomy fluid (10 h) and colostomy fluid (24 h), respectively. The flavan‐3‐ol C‐glycosides under study, i.e. (+)‐epicatechin 8‐C‐β‐D‐glucopyranoside (1a), (+)‐epicatechin 6‐C‐β‐D‐glucopyranoside (1d), (+)‐catechin 6‐C‐β‐D‐galactopyranoside (2b), (+)‐catechin 6‐C‐β‐D‐rhamnopyranoside (3b) were analyzed in the incubation samples by HPLC‐DAD and HPLC‐DAD‐MS/MS. They were found to be stable in the course of incubation in saliva, simulated gastric juice and ileostomy fluid and underwent degradation in colostomy fluid. While the 6‐C‐β‐D‐glucopyranoside 1d was completely metabolized between 2 and 4 h, decomposition of the 6‐C‐β‐D‐galactopyranoside 2b reached only 16±2% within 4 h of incubation. Linear degradation rates of 1d and 2b in colostomy fluid differed significantly. As microbial metabolism of flavan‐3‐ols is known not to be influenced by the stereochemistry of the aglycon, varying degradation rates are ascribed to the effect of the sugar moiety. Based on these results we assume that flavan‐3‐ol C‐glycosides pass through the upper gastrointestinal tract (oral cavity, stomach and small intestine) unmodified and are then metabolized by the colonic microflora.
Correlation between proton transfer and 35Cl NQR frequency as well as molecular geometry of chloranilic acid in co‐crystals with some organic bases
Authors: Asaji Tetsuo , Seliger Janez , Žagar Veselko , Ishida Hiroyuki
Published: May 2010

Proton transfer in hydrogen‐bonded organic co‐crystals of chloranilic acid with some organic bases was investigated by nuclear quadrupole resonance (NQR) spectroscopy. The 35Cl NQR frequencies of chloranilic acid molecule as well as 14N NQR frequencies of the organic base molecule were measured with the conventional pulse methods as well as double‐resonance methods, respectively. The extent of proton transfer in the O···H···N hydrogen bond was estimated from Townes–Dailey analysis of the 14N NQR parameters. The 35Cl NQR frequency and molecular geometry of chloranilic acid are correlated to the extent of proton transfer in the protonation process of the organic base molecule. It is shown that the hydrogen bond affects the π‐electron system of chloranilic acid. Geometry dependence of the O···H···N hydrogen bond, i.e. the HN valence bond order versus the hydrogen‐bond geometry correlation is also discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of polymerically‐modified clay structure on the morphology and properties of UV‐cured polyurethane acrylate/clay nanocomposites
Authors: Chen Dan , Xu Yuanhua , Zang Yangling , Su Shengpei
Published: May 2010

Polyurethane acrylate (PUA)/clay nanocomposites were prepared by UV‐curing from a series of styrene‐based polymerically‐modified clays and PUA resin. Effect of the chemical structure of the polymeric surfactants on the morphology and tensile properties of nanocomposites has been explored. X‐ray diffraction (XRD) and transmission electron microscopy (TEM) experimental results indicated that surfactants having hydroxyl or amino groups show better dispersion and some of the clay platelets were fully exfoliated. However, the composites formed from pristine clay and other polymerically‐modified clays without hydroxyl or amino groups typically contained both tactoids and intercalated structure. The mechanical properties of PUA composites were greatly improved where the organoclays dispersed well. Thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) were carried out to examine the thermal properties of the composites. The results showed that the loading of polymerically‐modified clays do not effect the thermal stability, but increased the Tgs of PUA/clay composites. Copyright © 2010 John Wiley & Sons, Ltd.
An environmental friendly approach for recycling of post‐vulcanized fluoroelastomer scraps through high‐shear mechanical milling
Authors: Zhang Xinxing , Lu Canhui , Zheng Qingyu , Liang Mei
Published: May 2010

An environmental friendly approach for partial de‐crosslinking of post‐vulcanized fluoroelastomer (FKM) scraps through high‐shear mechanical milling has been developed for recycling of the FKM. The method not only overcomes the expensive use and recovery of organic solvents but also gives rise to reclaimed rubbers with superior mechanical properties. After 32 cycles of milling, the gel fraction of FKM decreased from its original 97.8% to 79.7%. The appearance of the –CF2‐associated peaks C1s spectra after mechanical milling confirmed the partial de‐crosslinking of FKM. The structure change of FKM sol part before and after mechanical milling was also investigated by Fourier transform infrared (FTIR) analysis and gel permeation chromatography (GPC) measurements. The reclaimed FKM exhibited excellent mechanical and thermal properties, indicating a strong potential for future applications. The tensile strength of FKM re‐vulcanizates is 6.6 MPa, retaining about 84% properties of virgin FKM vulcanizates (7.9 MPa), and the elongation at break was increased from 337.1% to 368.7%. Copyright © 2010 John Wiley & Sons, Ltd.
Elastic properties of large‐open‐mesh 2D braided composites: Model predictions and initial experimental findings
Authors: Ayranci Cagri , Romanyk Daniel , Carey Jason P
Published: May 2010

Conventional applications of two‐dimensional tubular braided composites mostly require closed‐mesh braiding; however, some stiffness‐critical applications may require use of open‐mesh braiding. Most likely candidates for the open‐mesh braided composites are in the medical field, such as braided catheters and stents. Analytical and experimental investigation of the open‐mesh braided tubular composites is very limited in the open literature; therefore, this study is an initial attempt to close this gap. The article investigates elastic properties of the open‐mesh braided composites (e.g., braided catheters) and open‐mesh composites with holes (i.e., stent‐like structures). Analytical results are also compared with that of experimental results. Findings may be used in design of braided medical tubular composites. POLYM. COMPOS., 31:2017–2024, 2010. © 2010 Society of Plastics Engineers
Facile synthesis of magnetic nanoparticle–coated single‐walled carbon nanotubes and its functional modification in epoxy resin
Authors: Shen Jianfeng , Qin Chen , Hu Yizhe , Li Na , Ye Mingxin
Published: May 2010

Magnetic single‐walled carbon nanotubes (SWCNTs) were synthesized in a process consisting of two steps: (a) covalent in situ polymerization and grafting of poly (acrylic acid) (PAA) on the surface of SWCNTs, followed by (b) thermal decomposition of ferric triacetylacetonateto produce magnetite nanoparticles on the PAA‐grafted SWCNTs. It was demonstrated that magnetic nanoparticle–coated SWCNTs dispersed in water by sonication would respond to an external magnetic field. On such functionalization, the reorientation of SWCNTs in an epoxy matrix could be produced using a magnet. This endowed the composites with desirable magnetic and mechanical properties. POLYM. COMPOS., 31:2035–2041, 2010. © 2010 Society of Plastics Engineers
Studies on heterogeneous nucleation effect of dispersing intercalated montmorillonite clay platelets in polyaniline matrix
Authors: Cheng Hsiu‐Yu , Weng Chang‐Jian , Liou Shir‐Joe , Yeh Jui‐Ming , Liu Sung‐Po
Published: May 2010

In this article, a series of nanocomposite materials that consisted of emeraldine base (EB) of polyaniline (PANI) and montmorillonite (MMT) clay were prepared by effectively dispersing the inorganic MMT clay platelets into organic PANI matrix via in situ chemically oxidative polymerization. Organic aniline monomers were first intercalated into the interlayer regions of organophilic clay hosts and followed by an one‐step oxidative polymerization with ammonium persulfate as oxidant. The as‐synthesized PANI‐clay nanocomposite (PCN) materials were characterized by Fourier‐Transformation infrared spectroscopy and transmission electron microscopy. It should be noted that the EB of PANI in the presence of dispersed intercalated MMT clay platelets was found to display an observable enhancement in polymer crystallinity as compared with that of neat PANI based on series of investigations of wide‐angle powder X‐ray diffraction patterns and differential scanning calorimetric studies. This remarkable increase of polymer crystallinity might be resulted from the effective heterogeneous nucleation effect of dispersed clay platelets existed in PCN materials. The surface morphology study of PCN materials was further evaluated by polarizing optical microscopy, scanning electron microscopy, and atomic force microscopy. POLYM. COMPOS., 31:2049–2056, 2010. © 2010 Society of Plastics Engineers
Effects of curing agent and carbon black filler loading on carbonization behavior of phenolic‐carbon black composites
Authors: Ravikumar N.L. , Kar Kamal K. , Sarkar S. , Sathiyamoorthy D.
Published: May 2010

The effects of curing agent (p‐toluene sulfonic acid, PTSA) concentration, i.e., 1.0, 1.5, 2.0, 2.5, and 3.0 wt% on neat phenolic resin (in absence of carbon black) were investigated through the measurement of density, weight loss, linear shrinkage, and mechanical properties under compression mode to understand the carbonization behavior of carbon–carbon composite. The study was carried out after curing, postcuring, and carbonization. Also, thermogravimetric analysis was used to study the effects of curing agent concentration on thermal stability and kinetic parameters (i.e., activation energy, order of decomposition, pre‐exponential term, etc). The kinetic parameters were evaluated by using four single heating rate techniques namely Friedman, Coats‐Redfern, Freeman‐Carroll, and Chang methods. Further, to study the effects of both carbon black filler loading and carbonization temperature, phenolic‐carbon black composites were prepared at the loading of 10, 20, 30, 40 wt% using 1.5 wt% of PTSA. These were also investigated through density, weight loss, and shrinkage measurements after curing, postcuring, and carbonizing at the temperature of 600, 1000, and 1400°C in nitrogen atmosphere. To analyze the evolution of carbon phase X‐ray diffraction study was carried out for the carbonized samples. Finally, cured, postcured and carbonized composite samples were subjected to compression tests to study the compression strength and modulus. POLYM. COMPOS., 31:2069–2078, 2010. © 2010 Society of Plastics Engineers
8th HUPO World Congress: The Human Disease Glycomics/Proteomics Initiative (HGPI) Session 26 September 2009, Toronto, Canada
Authors: Narimatsu Hisashi
Published: May 2010

The Human Disease Glycomics/Proteomics Initiative (HGPI) Session at the HUPO World Congress was held in Toronto on 26 September 2009. In this report, we summarize the presentation of the HGPI workshop as follows: (i) The results of the past HGPI pilot studies (first and second) in which we analyzed N‐ and O‐linked glycans using standard glycoproteins (i.e. first: N‐linked glycan analysis of transferrin and IgG; second: O‐linked glycan analysis of IgA). (ii) The recent progresses of the current HGPI third pilot study. The third analytical pilot study is in progress to perform the two tasks, which are glycan structural analysis and identification of proteins which carry specific carbohydrate antigen (Lewis X antigen) using cancer cells (i.e. L428, U937, and SK‐N‐SH), under the theme of “Glyco‐Biomarker Discovery”. Finally, recently advanced glycomic and glycoproteomic analyses were also reported.
Optical absorption losses in metal layers used in thin film solar cells
Authors: Remes Zdenek , Holovsky Jakub , Purkrt Adam , Izak Tibor , Poruba Ales , Vanecek Milan , Dagkaldiran Ümit , Yates Heather M. , Evans Philip , Sheel David W.
Published: May 2010

We apply optical transmittance and reflectance spectroscopy, photothermal deflection spectroscopy (PDS) and laser calorimetry (LC) to evaluate optical absorption losses at rough interface between thin conductive oxide (TCO) and metal films used as backreflectors and electrical contacts in thin film solar cells. The paper proposes a simple method how to model the dielectric function of rough metal layers used in thin film solar cells. We show that the rough metal layer optically behaves as a semi‐infinite layer with modified dielectric function calculated by the Landau–Lifshitz–Looyenga (LLL) model from the dielectric function of a smooth metal, the dielectric function of TCO and just one free parameter that needs to be found by fitting the total optical absorptance. This approach can be used to simplify the modelling of the optical properties of thin film solar cells.
Waveguide design of green InGaN laser diodes
Authors: Lermer Teresa , Schillgalies Marc , Breidenassel Andreas , Queren Désirée , Eichler Christoph , Avramescu Adrian , Müller Jens , Scheibenzuber Wolfgang , Schwarz Ulrich , Lutgen Stephan , Strauss Uwe
Published: May 2010

In this paper we investigate the waveguiding (WG) of direct green InGaN laser diodes grown on c‐plane GaN substrates. The problem of parasitic modes emerges due to the reduced refractive index difference between the GaN waveguide and AlGaN cladding layers for green compared to blue emitting laser diodes. We discuss several approaches to avoid substrate modes. We investigate different materials and designs for optimized WG of green InGaN laser diodes using a 1D transfer matrix simulation tool.
Laterally overgrown GaN/InGaN multi‐quantum well heterostructures: Electrical and optical properties
Authors: Polyakov Alexander , Govorkov Anatoliy , Smirnov Nikolay , Markov Alexander , Lee In‐Hwan , Ahn Haeng‐Keun , Karpov Sergey , Pearton Stephen
Published: May 2010

Multi‐quantum well (MQW) GaN/InGaN structures prepared by epitaxial lateral overgrowth were characterized by various techniques to better understand the difference of the materials properties and heterostructure operation in the wing and window regions. Detailed interpretation of the characterization data is given, invoking quantum‐mechanical simulation of the grown heterostructures.
GaN/AlGaN nanostructures for intersubband optoelectronics
Authors: Tchernycheva M. , Macchadani H. , Nevou L. , Mangeney J. , Julien F. H. , Kandaswamy P. K. , Wirthmüller A. , Monroy E. , Vardi A. , Schacham S. , Bahir G.
Published: May 2010

We have investigated intraband absorptions in GaN/AlN QDs for ultrafast all‐optical switching applications at telecommunication wavelengths. Using time‐resolved pump‐probe experiments the electron lifetime in the excited state of the QDs is measured to be 165 fs. Intraband absorption saturation experiments reveal a record low switching energy. We then investigate quantum cascade ISB photodetectors based on GaN/AlGaN QWs and show that mesa devices with 17 × 17 µm2 size provide a frequency response above 10 GHz at 1.5 µm wavelength.
Architecture of nano‐ and microdimensional building blocks
Authors: Grundmann M.
Published: May 2010

The architecture of nano‐ and microdimensional building blocks has been investigated within the research group FOR 522 funded by the Deutsche Forschungsgemeinschaft. The main results are summarized in a series of papers following this article. Nanowires have been investigated for III–V‐ and II–VI‐semiconductors and thermoelectric materials. Structures with curvature – screws, spirals, cylindrical tubes, and scrolls – have been achieved using substrate rotation during material deposition under glancing angle and employing strain, either between lattice planes in incommensurable structures or due to lattice mismatch in epitaxial heterostructures. The modification of physical properties due to conformal coverage with thin films, quantum wells, and dielectric Bragg mirrors has been investigated.

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Schematic geometry of various investigated structures: Nanowires (GaAs, InAs, GaN, ZnO, Bi2Te3), spirals (silicon), tubes (cylindrite, a sulfosalt, FePb3Sn4Sb2S14), and scrolls (InGaAs/BGaAs/GaAs), from left to right.
Theoretical study of mechanism of extraction reaction between silylene carbene and its derivatives and ethylene oxide
Authors: Lu Xiu Hui , Che Xin , Han Jun Feng , Shi Le Yi , Lian Zhen Xia
Published: May 2010

The mechanism of the oxide extraction reaction between singlet silylene carbene and its derivatives [X2Si = C: (X = H, F, Cl, CH3)] and ethylene oxide has been investigated with density functional theory, including geometry optimization and vibrational analysis for the involved stationary points on the potential energy surface. The energies of the different conformations are calculated by B3LYP/6‐311G(d,p) method. From the potential energy profile, it can be predicted that the reaction pathway of this kind consists two steps, the first step is the two reactants firstly form an intermediate (INT) through a barrier‐free exothermic reaction; the second step is the INT then generates a product via a transition state (TS). This kind reaction has similar mechanism, when the silylene carbene and its derivatives [X2Si = C: (X = H, F, Cl, CH3)] and ethylene oxide close to each other, the shift of 2p lone electron pair of O in ethylene oxide to the 2p unoccupied orbital of C in X2Si = C: gives a p → p donor–acceptor bond, thereby leading to the formation of INT. As the p → p donor–acceptor bond continues to strengthen (that is, the CO bond continues to shorten), the INT generates product (P + C2H4) via TS. It is the substituent electronegativity, which mainly affects the extraction reactions. When the substituent electronegativity is greater, the energy barrier is lower, and the reaction rate is greater. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Sequence‐dependent proton‐transfer reaction in stacked GC pair III: The influence of proton transfer to conductivity
Authors: Nakanishi Yasuyuki , Matsui Toru , Shigeta Yasuteru , Kitagawa Yasutaka , Saito Toru , Kataoka Yusuke , Kawakami Takashi , Okumura Mitsutaka , Yamaguchi Kizashi
Published: May 2010

We have computed current–voltage character of natural DNA and its proton‐transferred structure by scattering theory based on density functional theory. The current is not observed if the electron path contains only hydrogen bonding such as one base pair. The current becomes larger if the electron path contains π–π stacking molecule such as two base pairs. We also found that the conductivity of pseudo‐ion pair (C+G−/G−C+), which is derived from proton‐transfer reaction in CG/GC, differs from that of the original structure. On the other hand, the current changes dramatically if the electrode connects to guanine or cytosine, which can be explained by the difference of electron affinities. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Is fullerene C60 large enough to host an aromatic molecule?
Authors: Mazurek Aleksander P. , Sadlej‐Sosnowska Nina
Published: May 2010

The endohedral complex of fullerene with benzene was studied with computational chemistry methods. The changes of structural parameters, such as bond lengths of host and guest and volume increments accompanying complex formation, were investigated, as well as the transfer of electron density between host and guest. The results obtained with three DFT functionals, which were recently designed for weak interactions, were compared. A three‐centered hydrogen bond between H atom of benzene and two atoms of fullerene was found. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
A new property of atom energies
Authors: Pearson Ralph G.
Published: May 2010

A proof is given that the total nuclear‐electron attraction energy should be constant for all the light atoms, when calculated by various trial wave functions. If hydrogenic wave functions for effective nuclear charges are picked as standards, it is easy to calculate the value of this energy. This constraint should be added to the usual constraints (minimum energy and the virial theorem) of the variation method. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Molecular frame photoelectron angular distributions for H2 ionization by single and trains of attosecond XUV laser pulses
Authors: Sanz‐Vicario J. L. , Pérez‐Torres J. F. , Morales F. , Plésiat E. , Martín F.
Published: May 2010

The delayed autoionization of H2 doubly excited states into channels of different inversion symmetry gerade and ungerade is investigated by using pulses of attosecond duration (isolated or packed in trains), linearly polarized along the molecular axis. It has been shown in previous work, by using XUV laser pulses with durations of 4 fs or longer, that the molecular frame photoelectron angular distributions (MFPAD) associated with the dissociative channel H+ + H(nℓ) are not symmetric with respect to the inversion center of the molecule. In contrast, the MFPADs become symmetric for shorter fs pulses. Here we show that, although this is still the case for pulses of attosecond duration, the combination of two of these pulses with a controlled time delay may still lead to asymmetric MFPADs. From the analysis of the time evolution of the calculated MFPADs, we propose a way to elucidate autoionization lifetimes of molecular resonant states. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2462–2471, 2010
Numerical evidence of two aligned conical intersections induced by the Renner effect in bent C2H cation
Authors: Halász G. J. , Vibók Á.
Published: May 2010

Characterizing and localizing conical intersections1 are important for the control of molecular processes. In an earlier work (see, e.g., Halász et al., J Chem Phys 2007 126, 154309), applying topological phase consideration, we showed, that the Renner effect in polyatomic molecules with more than three nuclei is necessarily accompanied by a so called symmetry‐allowed conical intersection. By using a perturbational approach Vértesi and Englman (J Phys B: At Mol Opt Phys 2008 41, 025102) pointed out that not only one as it was revealed by us, but also two aligned conical intersections will be created in the slightly bent Renner–Teller tetra‐atomic radical cation C2H. The aim of this present work is to support this finding both by symmetry arguments and by ab initio calculations. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
The subsystem functional scheme: The Armiento‐Mattsson 2005 (AM05) functional and beyond
Authors: Mattsson Ann E. , Armiento Rickard
Published: May 2010

The subsystem functional scheme (Kohn and Mattsson, Phys Rev Lett 1998, 81, 3487; Armiento and Mattsson Phys Rev B 2002, 66, 165117) is a recently proposed framework for constructing exchange‐correlation density‐functionals for use in density functional theory based calculations. The fundamental principle is to describe the physics in a real material by mapping onto model systems that exhibit the characteristic physics in each separate part of the real system. The local density approximately (LDA) functional can be seen as a subsystem functional: in all parts of the real material the assumption is that the needed physics is well described by the uniform electron gas model system. It is well known that this assumption is very accurate for surprisingly large classes of materials. The Armiento–Mattsson 2005 (AM05) (Armiento and Mattsson, Phys Rev B 2005, 72, 085108; Mattsson and Armiento, Phys Rev B 2009, 79, 155101) functional takes this a step further by distinguishing between two separate types of regions in a real material, one type that is assumed to be well described by the uniform electron gas, and the other type of region assumed to be well described by a surface model system. AM05 gives a consistent improvement over LDA. One important consequence of the subsystem functional scheme is that it is known what physics is included in a functional. Based on the performance of AM05 for a number of different systems, we discuss where the model systems included are enough and when additional physics need to be included in a new functional. Improvement of AM05 is possible by fine‐tuning the details in the construction. But a new major step in accuracy improvement is only expected if new physics is integrated in a functional via an additional model system. We discuss what type of physics would be needed and what model systems could be used for this next step beyond AM05. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
An examination of change profiles in reusable and non‐reusable software systems
Authors: Gupta Anita , Cruzes Daniela , Shull Forrest , Conradi Reidar , Rønneberg Harald , Landre Einar
Published: May 2010

This paper reports on an industrial case study in a large Norwegian Oil and Gas company (StatoilHydro ASA) involving a reusable Java‐class framework and two applications that use that framework. We analyzed software changes from three releases of the reusable framework, called Java Enterprise Framework (JEF), and two applications reusing the framework, called Digital Cargo File (DCF) and Shipment and Allocation (S&A). On the basis of our analysis, we found the following: (1) Profiles of change types for the reused framework and the applications are similar, specifically, perfective changes dominate significantly. (2) Although on observing the mean value adaptive changes are more frequent and are active longer in JEF and S&A, these systems went through less refactoring than DCF. For DCF, we saw that preventive changes were more frequent and were active longer. (3) Finally, we found that designing for reuse seems to lead to a long‐term payoff in relation to non‐reusable software systems. Copyright © 2010 John Wiley & Sons, Ltd.
A comparative investigation of the packing and flow properties of sweet potato (Ipomoea batatas) starches and their potential use in solid dosage formulations
Authors: Riley Cliff K. , Adebayo Sarafadeen A.
Published: May 2010

A comparative evaluation of the flow and packing properties of starch products extracted from three sweet potato (Ipomoea batatas) cultivars grown in Jamaica was done with a view to assessing their suitability as excipients in solid dosage formulations. Significant differences were observed in the properties of the starches obtained from the different sweet potato cultivars (p<0.05). The mean granular diameter ranged from 13.4 ± 0.42 (Eustace) to 20 ± 0.85 µm (Clarendon). Clarendon starch was found to be the least cohesive and bulkiest with Compressibility Index (CI) of 32.69 ± 0.28%, angle of internal flow (θi) of 12.70 ± 0.12° and maximum volume reduction (a) of 35.65 ± 1.02%, while Eustace was the most cohesive and least bulky with CI values of 37.74 ± 1.06%, θi of 19.68 ± 0.22°, and a of 43.60 ± 0.95%. The starch powders had similar bulk densities and packing fraction (p>0.05). All other fundamental properties calculated from the projected mean diameter including surface mean diameter (dvs), Heywood equivalent diameter (de) and specific surface (Sw) varied significantly (p<0.05) in a cultivar‐dependent manner but with no consistent pattern of variation among cultivars. The results indicate intravarietal variations in the packing and cohesive properties of the starches studied which may be a result of variations in the fundamental properties of the granules. These differences in properties may prove significant when predicting the behaviour of starches during handling and pharmaceutical formulations.
Determination of the mass‐specific distribution of the substituents in cationic starch derivatives
Authors: Radosta Sylvia , Ulbrich Marco , Vorwerg Waltraud
Published: May 2010

The mass‐specific charge distribution in molar mass fractions of cationic starch derivatives was investigated. The molar mass fractions were produced by semi‐preparative SEC (SP‐SEC). The derivatives were cut into an amylopectin‐rich fraction F1, an intermediate fraction F2, containing low molar mass amylopectin and high molar mass amylose, and an amylose‐rich fraction F3. The weight‐average molar mass (Mw) and molar mass distribution (MMD) of the fractions were determined by SEC with multi‐angle laser light scattering (SEC‐MALLS). The mass‐specific charge of each fraction was calculated from the consumption of anionic titrant solution using polyelectrolyte titration (PET) in combination with particle charge detection (PCD). The difference in substituent distribution between the fractions was tested by the Student's t‐test. The weight‐average molar mass of the starch derivatives was not dependent on the degree of substitution (DS) or the derivatization process. Depending on the DS value or derivatization process, different substituent distributions were observed. The results for the mass‐specific charge distribution in different molar mass fractions of cationic starch derivatives with graded DS between 0.015 and 0.130 from the slurry process were discussed. The heterogeneity of substituent distribution decreased with increasing DS of the starch derivative. This was the case for samples from both the slurry and semi‐dry processes. The heterogeneity of derivatization was highest for low DS samples up to DS 0.03, with the amylopectin‐rich fraction incorporating more charges than the amylose‐rich fraction. This was more pronounced for the sample from the slurry process than from the semi‐dry process.
Rheological and functional properties of flours from banana pulp and peel
Authors: Bertolini Andréa C. , Bello‐Pérez Luis A. , Méndez‐Montealvo Guadalupe , Almeida Claudia A. S. , Lajolo Franco
Published: May 2010

Unripe banana flour can be an alternative to minimize post‐harvest loss and to increase the aggregate value of banana fruit. Flour from unripe banana is rich in phytosterols and resistant starch, being proposed as health food. Flours from unripe banana peel and pulp were evaluated on their composition, phytosterols content, thermal and rheological properties, and pasting profiles. High amounts of β‐sitosterol, campesterol, and stigmasterol were found in flour from banana peel. These samples showed lower viscosity values of pasting profiles, lower energy enthalpy on gelatinization, and higher temperature of gelatinization than those ones from pulp. Anti‐oxidant treatment of fruits with citric acid does not change pasting profiles of flours from pulp, but resulted in slight increase in viscosity, suggesting that structure of starch could be modified by acidification.