bluuebunny/crossref_metadata_2025 huggingface dataset:
Survey of the year 2008: applications of isothermal titration calorimetry
Authors: Falconer Robert J. , Penkova Anita , Jelesarov Ilian , Collins Brett M.
Published: March 2010

Isothermal titration calorimetry (ITC) is a fast, accurate and label‐free method for measuring the thermodynamics and binding affinities of molecular associations in solution. Because the method will measure any reaction that results in a heat change, it is applicable to many different fields of research from biomolecular science, to drug design and materials engineering, and can be used to measure binding events between essentially any type of biological or chemical ligand. ITC is the only method that can directly measure binding energetics including Gibbs free energy, enthalpy, entropy and heat capacity changes. Not only binding thermodynamics but also catalytic reactions, conformational rearrangements, changes in protonation and molecular dissociations can be readily quantified by performing only a small number of ITC experiments. In this review, we highlight some of the particularly interesting reports from 2008 employing ITC, with a particular focus on protein interactions with other proteins, nucleic acids, lipids and drugs. As is tradition in these reviews we have not attempted a comprehensive analysis of all 500 papers using ITC, but emphasize those reports that particularly captured our interest and that included more thorough discussions we consider exemplify the power of the technique and might serve to inspire other users. Copyright © 2010 John Wiley & Sons, Ltd.
Do all patients with carcinoma of the esophagus benefit from treatment at teaching facilities?
Authors: Cheung Michael C. , Koniaris Leonidas G. , Yang Relin , Zhuge Ying , MacKinnon Jill A. , Byrne Margaret M. , Franceschi Dido
Published: March 2010

Background

We sought to determine whether patients with esophageal carcinoma benefit from regionalization of care.

Methods

The Florida Cancer Data System (FCDS) and the Agency for Health Care Administration data sets (1998–2002) were merged and queried.

Results

A total of 5,041 patients (87.6% Caucasian vs. 11.1% African American (AA)) demonstrated a median survival time of 9.8 months overall and 23.4 months following surgical resection (P < 0.001). Adenocarcinoma arose predominantly in Caucasian patients (98.1%). Patients with adenocarcinoma (n = 2,248) derived a treatment benefit at a TF (HR = 1.35, P = 0.003), including an improved 90‐day mortality following surgery (2.1% vs. 4.0%, P < 0.001). Squamous cell carcinoma (SCC) arose predominantly in AA patients (91.6%). No overall survival benefit at TF was observed (HR = 1.01, P = 0.915), however a trend for reduced 90‐day surgical mortality was observed at TF (1.9% vs. 5.2%, P = 0.062). Multivariate analysis for adenocarcinoma demonstrates that poverty, lack of chemotherapy or surgery, and failure to provide treatment at a TF are independent predictors of worse survival. For SCC patients, AA race was a significant predictor of poorer survival while TF and poverty level were not.

Conclusions

These data suggest no benefit from potential regionalized care for patients with squamous histology, which disproportionately affects AA. J. Surg. Oncol. J. Surg. Oncol. 2010;102:18–26. © 2010 Wiley‐Liss, Inc.
Association of the C677T polymorphism in the methylenetetrahydrofolate reductase gene with sudden sensorineural hearing loss
Authors: Uchida Yasue , Sugiura Saiko , Ando Fujiko , Shimokata Hiroshi , Nakashima Tsutomu
Published: March 2010

Objectives/Hypothesis:

To investigate the recently reported association of the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene with sudden sensorineural hearing loss (SSNHL), we analyzed data from a community‐based Japanese population.

Study Design:

Nested case‐control study.

Methods:

Among 2,174 adults (1,096 males and 1,078 females) aged 40 to 79 years old who participated in the National Institute for Longevity Sciences–Longitudinal Study of Aging, we compared 33 cases of prevalent SSNHL, defined as a self‐reported otolaryngologist diagnosis, with the other cases. Multiple logistic regression was used to obtain odds ratios (ORs) for SSNHL in subjects with the MTHFR C677T polymorphism, with adjustment for other possibly influential factors under additive, dominant, and recessive genetic models.

Results:

The per‐allele ORs for SSNHL risk were 1.687 (95% confidence interval [CI], 1.023–2.780) in model 1, with adjustment for age and sex, and 1.654 (CI, 1.003–2.728) in model 2, with adjustment for smoking status, body mass index, histories of heart disease, hypertension, and diabetes, in addition to the factors in model 1. In model 3, a significant association between SSNHL and the C677T polymorphism was observed under all genetic models independent of factors including folic acid and homocysteine, although there were only 25 cases and 1,677 controls due to the addition of moderating factors.

Conclusions:

Our results suggest that the T allele of MTHFR C677T could be associated with susceptibility to SSNHL, and even imply that this mutation could be a risk factor that is independent of blood folic acid and homocysteine. Laryngoscope, 2010
Viscoelastic properties of phonosurgical biomaterials at phonatory frequencies
Authors: Kimura Miwako , Mau Ted , Chan Roger W.
Published: March 2010

Objectives/Hypothesis:

The purpose of this study was to examine the functional biomechanical properties of several injectable biomaterials currently or potentially used for vocal fold augmentation.

Study Design:

Rheometric investigation of phonosurgical materials in vitro.

Methods:

Linear viscoelastic shear properties of 3% bovine collagen (atelocollagen), micronized AlloDerm (Cymetra; LifeCell Corp., Branchburg, NJ), calcium hydroxylapatite (CaHA) (Radiesse; BioForm Medical, San Mateo, CA), and 2.4% cross‐linked hyaluronic acid (HA) gel (Juvéderm; Allergan, Inc., Irvine, CA) were quantified as functions of frequency covering the phonatory range, and compared to those of the human vocal fold cover. Measurements of elastic shear modulus (G′) and dynamic viscosity (η′) were made at up to 250 Hz with a controlled‐strain simple‐shear rheometer. Linear least‐squares regression was conducted to curve‐fit log G′ and log η′ versus log frequency, and statistical analysis was performed with one‐way analysis of variance.

Results:

Radiesse and Cymetra were found to be the stiffest and the most viscous materials, followed by Juvéderm and atelocollagen. There were significant differences in the magnitudes of G′ and η′ among the phonosurgical materials and the normal human vocal fold cover (p < .001), whereas there was no significant difference in the frequency dependence of G′ and η′ among the materials. Post hoc Tukey tests revealed significant differences (p < .05) in pairwise comparisons of the magnitudes of G′ and η′ among all materials and the vocal fold cover.

Conclusions:

These findings suggested that although these biomaterials may be injected lateral to the lamina propria for the treatment of glottic insufficiency, none of them are rheologically optimal for the functional reconstruction of the vocal fold lamina propria. Laryngoscope, 2010
Botulinum toxin injections for new onset bilateral vocal fold motion impairment in adults
Authors: Ekbom Dale C. , Garrett C. Gaelyn , Yung Katherine C. , Johnson Felicia L. , Billante Cheryl R. , Zealear David L. , Courey Mark S.
Published: March 2010

Objectives/Hypothesis:

Review of clinical experience and results using botulinum toxin type A (BTX) for the management of adult patients with respiratory compromise due to new onset bilateral vocal fold motion impairment (BVFMI).

Study Design:

Retrospective case series.

Methods:

The records of 11 patients from two institutions with respiratory compromise due to bilateral vocal fold motion impairment were reviewed. Age, sex, etiology of motion impairment, subjective response to BTX injections, changes in pulmonary function studies pre‐ and postinjection when available, the dosage of botulinum toxin required to achieve response, the number of injections per patient, and complications were reported.

Results:

All patients were over 18 years old. There were three male and eight female subjects. The etiology of BVFMI was due to previous anterior cervical surgery in nine patients and prolonged intubation in two. Ten patients reported symptomatic improvement and returned for an average of nine injections over the 10‐year period of study. The most common interval between injections was 3 months. In all patients the dose required to achieve symptomatic improvement was at least 2.5 mouse units injected into each vocal fold. One patient without relief of symptoms had bilateral cricoarytenoid joint fixation. Complications were limited to moderate dysphagia in one patient and breathy dysphonia in all patients.

Conclusions:

BTX injection into the vocal folds provides temporary relief of symptoms in airway obstruction in adult patients with BVFMI. Patients require an average of 2.5 units of botulinum injection into each vocal fold and have an average length of response of 3 months. BTX injection may be used as a form of temporary relief of airway obstruction in patients wishing to avoid ablative surgery or tracheotomy. Laryngoscope, 2010
Ambulatory pediatric otolaryngologic procedures in the United States: Characteristics and perioperative safety
Authors: Bhattacharyya Neil
Published: March 2010

Objectives/Hypothesis:

Determine the prevalence and safety of pediatric ambulatory otolaryngologic procedures in the United States.

Study Design:

Historical cohort study.

Methods:

All cases of pediatric otolaryngologic surgery were extracted from the National Survey of Ambulatory Surgery 2006 release. The population was characterized according to age, sex, and individual procedures performed. Rates of immediate perioperative complications were determined for arrest, malignant hyperthermia, hemorrhage, blood transfusion, and postoperative nausea/vomiting. Discharge status and unexpected medical return visits were tabulated. Complication rates for patients younger than 3 years were compared to the remaining cohort.

Results:

An estimated 1,410,546 ± 246,009 (± standard error) children underwent one or more pediatric otolaryngologic procedures in 2006 (mean age, 6.23 ± 0.19 years; 50.9% ± 2.2% male). The most common primary procedures performed were myringotomy and tube (551,222 cases), tonsillectomy with adenoidectomy (480,343 cases), adenoidectomy (81,048 cases), tonsillectomy (56,606 cases), myringotomy alone (27,691 cases), tympanostomy tube removal (21,446 cases), and close reduction of nasal fracture (15,230 cases). There were no reported cases of cardiac arrest, malignant hyperthermia, or blood transfusion. Postoperative nausea, vomiting, and perioperative bleeding occurred in 1.4%, 0.9%, and 0.2% of cases, respectively. Children younger than 4 years undergoing tonsillectomy were more likely to return to the surgery center (2.5%, P < .001) or have an unplanned admission (9.28%, P = .011) than older children.

Conclusions:

Pediatric otolaryngologic surgery is not only common but very safe in the ambulatory setting, with relatively minor complications occurring at rates of approximating 1%. Life‐threatening complications are exceedingly rare. Ambulatory tonsillectomy in children younger than 4 years requires careful selection. Laryngoscope, 2010
Miller fisher syndrome presents as an acute voice change to hypernasal speech
Authors: Howell Rebecca J. , Davolos Alexandra G. , Clary Matthew S. , Frake Paul C. , Joshi Arjun S. , Chaboki Houtan
Published: March 2010

The authors describe a 38‐year‐old man who presented with hypernasality, perioral and acroparesthesia, dyspnea, and dysphagia. Further evaluation revealed a diagnosis of Miller‐Fisher syndrome (MFS). MFS is a variant of Guillain‐Barré syndrome previously described in neurology and critical care journals; however, there is a paucity of work concerning this disease in the otolaryngology literature. An acute change in voice usually occurs secondary to inflammatory processes as seen after intubation and infection, but can occur as part of a more complex disease entity such as Guillain‐Barré or Miller‐Fisher syndrome. As such, clinicians should consider this in their evaluation of rhinolalia aperta. Laryngoscope, 2010
Solitary pulmonary nodule in the liver transplant candidate: Importance of diagnosis and treatment
Authors: Concejero Allan M. , Yong Chee-Chien , Chen Chao-Long , Lu Hung-I , Wang Chih-Chi , Wang Shih-Ho , Liu Yueh-Wei , Yang Chin-Hsiang , Cheng Yu-Fan , Jawan Bruno
Published: March 2010

Our objectives were to define the incidence and etiology of solitary pulmonary nodules (SPNs) in patients undergoing living donor liver transplantation (LDLT), describe a diagnostic approach to the management of SPNs in LDLT, and define the impact of SPNs on the overall survival of adult LDLT recipients. Nine patients (9/152, 5.9%) were diagnosed with an SPN on the basis of chest radiography findings during the pretransplant survey. All were male. The mean age was 52 years. All the patients had hepatitis B virus–related cirrhosis with hepatocellular carcinoma. All were asymptomatic for the lung lesion. All underwent contrast-enhanced chest computed tomography (CT) to verify the presence and possible etiology of the SPNs. In 3 cases, CT was used to definitely determine that there was no pulmonary nodule; in 2, CT led to a definite diagnosis of pulmonary tuberculosis. In 4, CT led to a definite identification of an SPN but not to an etiological diagnosis. Two patients underwent outright thoracoscopy and biopsy of their SPNs. Biopsy showed cryptococcosis in both patients. One received a therapeutic trial of an antituberculosis treatment, and repeat CT after 1 month showed a regression in the size of the SPN. A diagnosis of tuberculosis was made. One patient had an inconclusive whole body positron emission tomography scan and subsequently underwent thoracoscopy where biopsy showed tuberculosis. A concomitant malignancy, either primary lung cancer or metastasis from the liver tumor, was not identified. All patients were surviving with their original grafts and were lung infection–free. The overall mean posttransplant follow-up was 54 months (range = 33-96 months). Liver Transpl 16:760-766, 2010. © 2010 AASLD.
Gray matter correlations of cognition in incident Parkinson's disease
Authors: Dalaker Turi O. , Zivadinov Robert , Larsen Jan P. , Beyer Mona K. , Cox Jennifer L. , Alves Guido , Bronnick Kolbjorn , Tysnes Ole‐Bjorn , Antulov Ronald , Dwyer Michael G. , Aarsland Dag
Published: March 2010

We aimed to investigate whether mild cognitive impairment (MCI) in Parkinson's disease (PD) is characterized by region‐specific gray matter (GM) atrophy and to explore correlations between GM and cognition in PD. Magnetic resonance images of 42 newly diagnosed PD patients (of which 11 had MCI) and 37 normal controls were analyzed using voxel‐based morphometry. Analyses comparing groups showed no regional atrophy, and in patients there were no significant correlations between cognitive domain test performance and GM loss. In conclusion, GM atrophy does not seem to be a major feature of cognitive dysfunction in incident PD. © 2010 Movement Disorder Society
Progression of Parkinson's disease as evaluated by Hoehn and Yahr stage transition times
Authors: Zhao Ying Jiao , Wee Hwee Lin , Chan Yiong‐Huak , Seah Soo Hoon , Au Wing Lok , Lau Puay Ngoh , Pica Emmanuel Camara , Li Shu Chuen , Luo Nan , Tan Louis C.S.
Published: March 2010

This study was carried out to evaluate progression in Parkinson's disease (PD) by analyzing time taken to transit from one Hoehn and Yahr (H&Y) stage to the next stage and to investigate the variables that would be associated with H&Y transition times using a large PD database that contained prospectively collected information. Data were obtained from the movement disorder database of the National Neuroscience Institute in Singapore. Kaplan‐Meier (KM) survival analysis was adopted to investigate the time taken to progress through various H&Y stages. Cox regression analysis was used to examine the association between the baseline variables at the entry point of each H&Y stage and the progression to the next stage. A total of 695 patients (mean age: 65.2, male: 57.3%) were studied. Using KM analysis, the median time taken to transit from H&Y stage 1 to 2, 2 to 2.5, 2.5 to 3 were 20, 62, and 25 months, respectively; whereas the median time taken to progress from stage 3 to 4 and 4 to 5 were 24 and 26 months, respectively. Cox regression analysis revealed that older age‐at‐diagnosis, longer PD duration, and higher Unified Parkinson's Disease Rating Scale (UPDRS) motor scores at baseline were associated with a significantly faster progression through various H&Y stages. Gender and ethnicity were not associated with disease progression. In conclusion, H&Y transition time is a useful measure of disease progression in PD and may be utilized in clinical studies evaluating therapeutic interventions and prognostic factors in PD. © 2010 Movement Disorder Society
Ancient representation of Meige's syndrome in the Moche culture in the pre‐Columbian Peru
Authors: Martinez‐Castrillo Juan Carlos , Mariscal Ana , Garcia‐Ruiz Pedro
Published: March 2010

The Moches were a pre‐Columbian culture from Peru, who had a fine ceramic technique and used to represent diseases. One example is the potter presented here which represents a man with a probable Meige's syndrome and may be the first artistic representation of this disease. © 2010 Movement Disorder Society.
Agreement between self‐reported and pharmacy data on medication use in the Northern Finland 1966 Birth Cohort
Authors: Haapea Marianne , Miettunen Jouko , Lindeman Sari , Joukamaa Matti , Koponen Hannu
Published: March 2010

Objective: To compare self‐reported (SR) medication use and pharmacy data for major psychoactive medications and three classes of medications used for different indications, and to determine the socio‐economic factors associated with the congruence.

Methods: Postal questionnaire data collected in 1997 were compared with the register of the Social Insurance Institution of Finland on the reimbursed prescriptions purchased during 1997. Altogether 7625 subjects were included in this study. Drugs were categorized according to the Anatomical Therapeutic Chemical (ATC) system.

Results: Kappa values were 0.77, 0.68, 0.84, 0.92 and 0.55 for antipsychotics, antidepressants, antiepileptics, antidiabetics and beta‐blocking agents, respectively. Prevalence‐adjusted and bias‐adjusted kappa values were almost perfect (0.98–1.00). Reliability of antipsychotics use was better for married subjects than for those who were not married; and of antidepressants use for highly educated and married subjects than for those who were less educated and were not married. Altogether 414 (5.4%) responders and 285 (7.1%) non‐responders had used at least one of the selected medications.

Conclusion: Agreement between the SR and pharmacy data was moderate for psychoactive medication use. Even though data collected by postal questionnaire may underestimate the prevalence of medication use due to non‐participation it can be assumed accurate enough for study purposes. Copyright © 2010 John Wiley & Sons, Ltd.
Standardized protocol for a depletion of intramyocellular lipids (IMCL)
Authors: Ith Michael , Huber Philipp M. , Egger Andrea , Schmid Jean‐Paul , Kreis Roland , Christ Emanuel , Boesch Chris
Published: March 2010

Intramyocellular lipids (IMCL) are flexible fuel stores that are depleted by physical exercise and replenished by fat intake. IMCL or their degradation products are thought to interfere with insulin signaling thereby contributing to insulin resistance. From a practical point of view it is desirable to deplete IMCL prior to replenishing them. So far, it is not clear for how long and at which intensity subjects have to exercise in order to deplete IMCL. We therefore aimed at developing a standardized exercise protocol that is applicable to subjects over a broad range of exercise capacity and insulin sensitivity and allows measuring reliably reduced IMCL levels.

Twelve male subjects, including four diabetes type 2 patients, with wide ranges of exercise capacity (VO2peak per total body weight 27.9–55.8 ml*kg−1*min−1), insulin sensitivity (glucose infusion rate per lean body mass 4.7–15.3 mg*min−1*kg−1), and BMI (21.7–31.5 kg*m−2), respectively, were enrolled. Using 1H magnetic resonance spectroscopy (1H‐MRS), IMCL was measured in m.tibialis anterior and m.vastus intermedius before and during a depletion protocol of a week, consisting of a moderate additional physical activity (1 h daily at 60% VO2peak) and modest low‐fat (10–15%) diet.

Absolute IMCL‐levels were significantly reduced in both muscles during the first 3 days and stayed constant for the next 3 days of an identical diet/exercise‐scheme. These reduced IMCL levels were independent of insulin sensitivity, yet a tendency to lower depleted IMCL levels has been observed in subjects with higher VO2peak.

The proposed protocol is feasible in subjects with large differences in exercise capacity, insulin sensitivity, and BMI, leading to reduced IMCL levels that neither depend on the exact duration of the depletion protocol nor on insulin sensitivity. This allows for a standardized preparation of IMCL levels either for correlation with other physiological parameters or for replenishment studies. Copyright © 2010 John Wiley & Sons, Ltd.
Leukocyte adhesion deficiency‐III in an African‐American patient
Authors: Sabnis Himalee , Kirpalani Anjali , Horan John , McDowall Alison , Svensson Lena , Cooley Anthony , Merck Tara , Jobe Shawn , Hogg Nancy , Briones Michael
Published: March 2010

Leukocyte adhesion deficiency‐III (LAD‐III) is a rare disorder characterized by abnormal signaling to β integrins, leading to defective leukocyte adhesion and chemotaxis and platelet aggregation. Here we present the first case of an African‐American female infant with this disorder. She had history of multiple infections, bleeding, and leukocytosis since birth. She was successfully treated with allogeneic bone marrow transplant using a reduced intensity‐conditioning regimen. Mutations in KINDLIN‐3 have been described in LAD‐III but the mutations in KINDLIN‐3 in her case are unique. Pediatr Blood Cancer 2010;55:180–182. © 2010 Wiley‐Liss, Inc.
Self‐limiting sternal tumors of childhood (SELSTOC)
Authors: te Winkel M.L. , Lequin M.H. , de Bruyn J.R. , van de Ven C.P. , de Krijger R.R. , Pieters R. , van den Heuvel‐Eibrink M.M.
Published: March 2010

Background

Because a sternal mass is often alarming, it is important to identify the clinical features of benign processes.

Procedure

Data on clinical presentation, diagnostics, treatment and outcome of pediatric patients presenting with a sternal tumor between 2001 and 2009 were collected from medical records.

Results

Among the 1,700 children who were referred to our pediatric‐oncology center, 14 presented with a rapidly growing sternal mass. All patients (10 males) were Caucasian and median age was 16 (range: 7–50) months. Reported symptoms were local pain (n = 7) and/or raised body temperature (n = 5). No major preceding traumas were reported. Physical examination revealed solid tumors with a median diameter of 3 (range: 1–4.5) cm in a pre‐sternal/para‐sternal location. Half of the patients showed red/blue discoloration of the skin. On radiology, dumbbell‐shaped lesions extended to the area behind the sternal bone, involving the cartilage, leading to increased distance between ossification centers. Histopathology at diagnosis was available from five patients and showed aspecific chronic or acute inflammation (n = 4) and a reactive osteochondromatous lesion (n = 1). Laboratory infection parameters were not/only slightly raised and microbiologic cultures were negative in all patients. All tumors decreased in size within 1 month, in both patients with and without antibiotics. On physical examination the tumors disappeared within 6 months.

Conclusions

This study reports 14 young children with a rapidly growing sternal mass due to aseptic inflammation, that we named self‐limiting sternal tumor of childhood (SELSTOC). To prevent invasive diagnostic interventions and unnecessary treatment, we advocate a wait‐and‐see approach with close follow‐up in the first weeks. Pediatr Blood Cancer 2010;55:81–84. © 2010 Wiley‐Liss, Inc.
Strategy for comprehensive identification of human N‐myristoylated proteins using an insect cell‐free protein synthesis system
Authors: Suzuki Takashi , Moriya Koko , Nagatoshi Kei , Ota Yoshinobu , Ezure Toru , Ando Eiji , Tsunasawa Susumu , Utsumi Toshihiko
Published: March 2010

To establish a strategy for the comprehensive identification of human N‐myristoylated proteins, the susceptibility of human cDNA clones to protein N‐myristoylation was evaluated by metabolic labeling and MS analyses of proteins expressed in an insect cell‐free protein synthesis system. One‐hundred‐and‐forty‐one cDNA clones with N‐terminal Met‐Gly motifs were selected as potential candidates from ∼2000 Kazusa ORFeome project human cDNA clones, and their susceptibility to protein N‐myristoylation was evaluated using fusion proteins, in which the N‐terminal ten amino acid residues were fused to an epitope‐tagged model protein. As a result, the products of 29 out of 141 cDNA clones were found to be effectively N‐myristoylated. The metabolic labeling experiments both in an insect cell‐free protein synthesis system and in the transfected COS‐1 cells using full‐length cDNA revealed that 27 out of 29 proteins were in fact N‐myristoylated. Database searches with these 27 cDNA clones revealed that 18 out of 27 proteins are novel N‐myristoylated proteins that have not been reported previously to be N‐myristoylated, indicating that this strategy is useful for the comprehensive identification of human N‐myristoylated proteins from human cDNA resources.
Preparation of isotactic‐rich poly(dimethyl vinylphosphonate) and poly(vinylphosphonic acid) via the anionic polymerization of dimethyl vinylphosphonate
Authors: Kawauchi Takehiro , Ohara Minori , Udo Masaru , Kawauchi Mariko , Takeichi Tsutomu
Published: March 2010

A vinylphosphonate monomer, dimethyl vinylphosphonate (DMVP), has been polymerized by anionic initiators. Anionic polymerization of DMVP with tert‐butyllithium (t‐BuLi) in combination with a Lewis acid, tributylaluminum (n‐Bu3Al), in toluene proceeded smoothly to give an isotactic‐rich poly(dimethyl vinylphosphonate) (PDMVP) with relatively narrow molecular weight distribution. Although all the PDMVPs were soluble in water, the isotactic‐rich PDMVP was insoluble in acetone and in chloroform which are good solvents for an atactic PDMVP prepared by radical polymerization. The isotactic‐rich PDMVP showed higher thermal property than that of the atactic PDMVP. Moreover, we successfully prepared poly(vinylphosphonic acid) (PVPA) through the hydrolysis of the isotactic‐rich PDMVP, which formed a highly transparent, self‐standing film. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1677–1682, 2010
Effect of conjugated core building block dibenzo[a,c]phenazine unit on π‐conjugated electrochromic polymers: Red‐shifted absorption
Authors: Unver Elif Kose , Tarkuc Simge , Udum Yasemin Arslan , Tanyeli Cihangir , Toppare Levent
Published: March 2010

A comparative investigation was undertaken for the electrosynthesis and electrochemical properties of three different electroactive polymers having a conjugated core building block, dibenzo[a,c]phenazine. A series of monomers has been synthesized as regards to thiophene based units; thiophene, 3‐hexyl thiophene, and 3,4‐ethylenedioxythiophene. The effects of different donor substituents on the polymers' electrochemical properties were examined by cyclic voltammetry. Introducing highly electron‐donating (ethylene dioxy) group to the monomer enables solubility while also lowering the oxidation potential. The planarity of the monomer unit enhances π‐stacking and consequently lowering the Eg from 2.4 eV (PHTP) to 1.7 (PTBP). Cyclic voltammetry and spectroelectrochemical measurements revealed that 2,7‐bis(4‐hexylthiophen‐2‐yl)dibenzo[a,c]phenazine (HTP) and 2,7‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)dibenzo[a,c]phenazine (TBP) possessed electrochromic behavior. The colorimetry analysis revealed that while PTBP have a color change from red to blue, PHTP has yellow color at neutral state and blue color at oxidized state. Hence the presence of the phenazine derivative as the acceptor unit causes a red shift in the polymers' absorption to have a blue color. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1714–1720, 2010
Synthesis and characterization of ionic conducting sulfonated polybenzimidazoles
Authors: Jouanneau Julien , Gonon Laurent , Gebel Gérard , Martin Vincent , Mercier Régis
Published: March 2010

By copolymerization of the disodium‐2,2′‐disulfonate‐4,4′‐oxydibenzoic acid (SODBA), the 4,4′‐oxybis(benzoic acid) (OBBA) with the bis 3,4‐(diaminophenyl)sulfone (BDAPS), a series of high molecular weight sulfonated polybenzimidazoles (sPBI) were prepared by varying the ratio of monomers SODBA/OBBA. Polymers with ion exchange capacity (IEC) ranging from 0 to 3.2 meqH+/g were obtained. The chemical structure of the sPBI was confirmed by NMR, Fourier‐transform infra‐red (FTIR). Although the sPBI display a very poor solubility in organic solvents, they are, in the ammonium salt form, soluble in polar aprotic solvents such as DMF, NMP, or DMSO. Tough and ductile membranes from solution casting method were prepared. The water uptake and the ionic conductivity were determined at 30 and 90 °C. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1732–1742, 2010
A facile strategy to modify TiO2 nanoparticles via surface‐initiated ATRP of styrene
Authors: Wang Wenping , Cao Hengming , Zhu Guojun , Wang Peng
Published: March 2010

A core‐shell hybrid nanocomposites, possessing a hard core of nano titanium dioxide (n‐TiO2) and a soft shell of brushlike polystyrene (PS), were successfully prepared by surface‐initiated atom transfer radical polymerization (ATRP) at 90 °C in anisole solution using CuBr/PMDETA as the catalyst, in the presence of sacrificial initiator. FTIR, 1H NMR, XPS, TEM, SEM, TGA, and DSC were used to determine the chemical structure, morphology, thermal properties, and the grafted PS quantities of the resulting products. TEM images of the samples provided direct evidence for the formation of a core‐shell structure. The thermal stabilities of the grafted polymers were dramatically elevated relative to that of pristine PS according to TGA results. DSC results demonstrated that the TiO2‐PS nanocomposites exhibited higher glass transition temperature (Tg) compared with pristine PS. The molecular weights of the free polymers formed by sacrificial initiator, which were similar to that of surface‐attached polymers were measured by GPC instrument which showed that the molecular weights of PS were well controlled with a relatively narrow polydispersity index (PDI < 1.2). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1782–1790, 2010
Facile electrochemical preparation of poly(9,9‐dichlorofluorene), a new polyfluorene derivative as green light emitter
Authors: Nie Guangming , Guo Qingfu , Wang Song , Zhang Shusheng
Published: March 2010

High‐quality poly(9,9‐dichlorofluorene) (PDCF), a new part soluble polyfluorene derivative, was easily synthesized electrochemically by direct anodic oxidation of 9,9‐dichlorofluorene (DCF) in boron trifluoride diethyl etherate (BFEE) containing 15% (by volume) trifluoroacetic acid (TFA). It was hard for DCF to deposit on the electrode in neutral solvents such as CH3CN system. This methodology may help promotion of researches to reveal unknown properties and applications of polyfluorene materials. PDCF films with conductivity of 3.3 × 10−2 S cm−1 obtained from this media show good redox activity and thermal stability. The structure and morphology of the polymer were studied by UV–vis, FTIR, 1H NMR spectra, and scanning electron microscopy, respectively. The results of quantum chemistry calculations and the spectroscopies of dedoped PDCF indicate that the polymerization of DCF mainly occurs via C(2) and C(7) position. Fluorescent spectral studies indicate that PDCF film with high fluorescence quantum yields and photochemical stability is a novel green light emitter. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1791–1799, 2010
Immobilization of capsaicin onto silica nanoparticle surface and stimulus properties of the capsaicin‐immobilized silica
Authors: Yamauchi Takeshi , Saitoh Tomoya , Shirai Kumi , Fujiki Kazuhiro , Tsubokawa Norio
Published: March 2010

To prepare silica nanoparticle having biorepellent activity, the immobilization of capsaicin onto hyperbranched poly(amidoamine) (PAMAM)‐grafted silica was investigated. Grafting of PAMAM onto a silica surface was achieved in a solvent‐free dry system using PAMAM dendrimer synthesis methodology. The immobilization of capsaicin was achieved by the reaction of hydroxyl groups of capsaicin with isocyanate groups of Silica‐PAMAM, which were introduced by the reaction of terminal amino groups of Silica‐PAMAM with hexamethylene diisocyanate. The immobilization of capsaicin was confirmed by thermal decomposition GC‐MS. The amount of capsaicin immobilized onto PAMAM‐grafted silica was determined to be 0.10 mmol/g. Capsaicin‐immobilized Silica‐PAMAM (Silica‐PAMAM‐Cap) was dispersed uniformly in water and Tyrode solution. Stimulus activity of Silica‐PAMAM‐Cap was estimated using two stimulus tests, that is a magnus test and a paw licking test, to sensory nerve of mice. As the result of magnus test, it was found that the Silica‐PAMAM‐Cap shows stimulus activity. It was found that elution of capsaicin could be depressed by immobilizing capsaicin onto Silica‐PAMAM from the result of paw licking test. In addition, the stimulus property of Silica‐PAMAM‐Cap to the human skin could be observed and it was found that Silica‐PAMAM‐Cap had acrid taste. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1800–1805, 2010
New colorless substrates based on polynorbornene‐chlorinated polyimide copolymers and their application for flexible displays
Authors: Choi Myeon‐Cheon , Hwang Jae‐Chul , Kim Chiwan , Ando Shinji , Ha Chang‐Sik
Published: March 2010

Novel polynorbornene (PNB)‐polyimide (PI) copolymers were synthesized based on poly(N‐phenyl‐exo‐norbornene‐5,6‐dicarboximide) (PPhNI) and chlorinated PI (BPDA/TCDB). Polynorbornene copolymers (PNCs) with diverse compositions of anhydride were synthesized via ring opening metathesis polymerization (ROMP) of N‐phenyl‐exo‐norbornene‐5,6‐dicarboximide (PhNI) and exo‐7‐oxanorbornene‐5,6‐dicarboxylic anhydride(exo‐NA), followed by copolymerization through a reaction with aromatic dianhydride (3,3′,4,4′‐biphenyltetra‐carboxylic dianhydride, BPDA) and tetrachlorinated diamine (2,2′,5,5′‐tetrachlorobenzidine, TCDB). The copolymer (PNIC) films exhibited good optical transparency with a transmittance of around 70% at 400 nm and a good thermal stability with a glass transition temperature at 276–300 °C. These flexible films also resisted most organic solvents and chemicals, such as methanol, acetone, tetrahydrofuran, N‐methylpyrrolidone, ethyl acetate, hydrochloric acid, sodium hydroxide, and hydrogen peroxide, etc. Indium tin oxide (ITO) coated thin films were prepared at various substrate deposition temperatures with a radio frequency (r.f.) planar magnetron sputtering system. The ITO thin films that were deposited onto the PNIC copolymer substrates had good electrical and optical properties. An organic light‐emitting device (OLED) was fabricated using the PNIC copolymer substrate with a structure of PNIC08/ ITO (anode)/hole‐transporting layer (HTL)/emitting & electron‐transporting layer (EM&ETL)/aluminum (cathode). The flexible OLED fabricated on the ITO‐grown PNIC substrate exhibited a performance that was comparable to corresponding ITO‐grown glass substrates. Therefore, the ITO‐grown PNIC substrate could possibly be a promising candidate as a substrate for flexible displays. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1806–1814, 2010
Combination of transition metal carbonyls and silanes: New photoinitiating systems
Authors: Tehfe Mohamad‐Ali , Lalevée Jacques , Gigmes Didier , Fouassier Jean Pierre
Published: March 2010

The recently developed silyl radical chemistry is used in combination with transition metal carbonyls MC (dimanganese(0) decacarbonyl; dirhenium decacarbonyl; cyclopentadienyl iron(II) dicarbonyl dimer) for both free radical promoted cationic photopolymerization (FRPCP) and free radical photopolymerization (FRP). The newly developed photoinitiating systems (MC/silane and MC/silane/iodonium salt) are highly efficient under air. Photopolymerization profiles obtained upon a visible light irradiation delivered by a xenon lamp show that high conversion can be easily achieved after a 400 s exposure. Sunlight irradiations under air can also lead to tack free coatings. The processes associated with the metal carbonyl radical/silane interactions are investigated by Laser Flash Photolysis (LFP) and ESR‐Spin Trapping (ESR‐ST) experiments. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1830–1837, 2010
Valero–McKee refinery propane release and fire
Authors: Holmstrom Donald , Lay James , Banks Johnnie , Kaszniak Mark , MacKenzie Cheryl , Parasram Vidisha
Published: March 2010

On February 16, 2007 a massive propane release occurred at the Propane Deasphalting Unit (PDA) of the Valero–McKee Refinery near Sunray, Texas. The resulting vapor cloud ignited, burning four workers, destroying the PDA, and causing significant knock‐on damage to adjacent pipe racks and equipment.

The US Chemical Safety and Hazard Investigation Board (CSB) investigation determined that water trapped in a piping dead‐leg froze during cold weather, cracking a 10″ diameter liquid propane line, and causing the initial release when warmer weather returned. The CSB identified dead‐leg identification and management, freeze protection, emergency isolation capability, and structural steel fire protection as key issues contributing to the incident.

Two near‐misses were associated with this incident; the release of over 2.5 tons of chlorine from containers adjacent to the PDA, and the inability of workers to access manual deluge valves protecting a nearby LPG storage sphere, which was impacted by the fire.

The CSB made recommendations to Valero, the American Petroleum Institute, the McKee Refinery, and the United Steelworkers and their local. © 2010 American Institute of Chemical Engineers Process Saf Prog 2010
Irradiation‐induced defects in InN and GaN studied with positron annihilation
Authors: Reurings Floris , Tuomisto Filip , Egger Werner , Löwe Benjamin , Ravelli Luca , Sojak Stanislav , Liliental‐Weber Zuzanna , Jones Rebecca E. , Yu Kin M. , Walukiewicz Wladek , Schaff William J.
Published: March 2010

We use positron annihilation to study 2‐MeV 4He+ irradiated and subsequently rapid‐thermal‐annealed InN grown by molecular‐beam epitaxy and GaN grown by metal‐organic chemical‐vapour deposition. The irradiation fluences were in the range 5 × 1014–2 × 1016 cm−2. In vacancies are introduced in the irradiation at a low rate of 100 cm−1, with their concentration saturating in the mid‐1017 cm−3 range at an irradiation fluence of 2 × 1015 cm−2. The annealing, performed at temperatures between 425 and 475 °C, is observed to result in an inhomogeneous redistribution of the In vacancies. The behaviour is opposite to GaN, where Ga vacancies are introduced at a much higher rate of 3600 cm−1 showing no detectable saturation. About half of the Ga vacancies are found to recover in the annealing, in agreement with previous studies, while the remaining Ga vacancies undergo no spatial redistribution.
The effects of concentration on the electronic and optical properties in CdxZn1−xS ternary alloys
Authors: Korozlu N. , Colakoglu K. , Deligoz E.
Published: March 2010

The structural, electronic and optical properties of CdxZn1−xS alloys have been studied using the first‐principles plane‐wave pseudopotential (PP) method within the local‐density approximations (LDAs). The effects of composition on lattice constants, bulk modulus, band gap, dielectric functions, refractive index, extinction coefficient and energy loss function are investigated. It has been found that the lattice constants and bulk modulus change as almost linear for these alloys. Calculated electronic structure and density of states (DOS) of CdxZn1−xS alloys are discussed in terms of the contribution of Zn d, Cd d and p and S s and p states. Our results agree well with the available data in the literature.
Nanostructures by diffraction mask projection laser ablation
Authors: Mäder Marisa , Höche Thomas , Gerlach Jürgen W. , Böhme Rico , Rauschenbach Bernd
Published: March 2010

The top‐down method diffraction mask projection laser ablation (DiMPLA) to produce large‐area substrate‐bound metal nanostructure matrices is discussed in detail. It involves phase mask projection and patterning of an ultra‐thin metal film. Investigations concerning the patterning process and parameter frontiers are presented along with results of different materials patterned with DiMPLA. The material combination of thin film and substrate used most is investigated precisely allowing conclusions about the structure formation process as well as possible applications. Presented possible applications include three different PVD techniques for templated nanostructure growth as well as first steps toward plasmonic applications of gold nanodot matrices.

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Top view of a gold nanodot matrix on a sapphire substrate.
Influence of substrate and temperature on the shape of deposited Fe, Co, and FeCo nanoparticles
Authors: Rosellen Wolfgang , Kleinhans Christian , Hückelkamp Volker , Bulut Furkan , Kleibert Armin , Bansmann Joachim , Getzlaff Mathias
Published: March 2010

In situ scanning tunneling measurements have been carried out on mass‐filtered supported Fe, Co, and FeCo alloy nanoparticles with diameters between 4 and 14 nm. These nanoparticles are prepared from the gas phase using a continuously working cluster source and are subsequently deposited on bare W(110) and Ni(111)/W(110) surfaces. The size and the crystallographic structure before deposition are determined by high resolution transmission electron microscopy (HRTEM), the height of the nanoparticles on the substrate by scanning tunneling microscopy (STM). Depending on the substrate the particles do not maintain their spherical shape after deposition. The melting at elevated temperatures results in an anisotropic elongation along the [001] direction of the W(110) substrate.

STM illustration of large Co nanoparticles deposited on an atomically flat W(110)‐surface.

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Displacive phase transition, structural stability, and mechanical properties of the ultra‐incompressible and hard MoN by first principles
Authors: Zhao Erjun , Wang Jinping , Wu Zhijian
Published: March 2010

The structural stability, electronic, and mechanical properties of MoN were investigated by use of the density functional theory. Nine structures were considered, i.e., hexagonal δ1‐MoN, δ2‐MoN, $\delta '_2$‐MoN, δ3‐MoN, δ4‐MoN, and wurtzite ZnS structures, cubic NaCl, zincblende, and CsCl structures. The calculated results indicated that δ3‐MoN is the ground state among the considered structures. The second‐order displacive phase transition has been found from δ3‐MoN to $\delta '_2$‐MoN with increase in pressure, in agreement with the experimental observation. $\delta '_2$‐MoN has the largest calculated bulk and shear moduli among the considered structures, followed by δ3‐MoN. The estimated hardness of $\delta '_2$‐MoN and δ3‐MoN is 34 and 29 GPa, respectively. Both of them are thermodynamically and mechanically stable. The compressibility along the c‐axis for both compounds is smaller than that for diamond and cubic boron nitride (c‐BN). The ideal strengths of $\delta '_2$‐MoN were discussed.

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The stress–strain relationship for $\delta '_2$‐MoN shows that the ideal tensile strength of 107.0 GPa along the 〈0001〉 direction is very large, which might have potential technological and industrial applications.
Using density functional theory to rationalise the mass spectral fragmentation of maraviroc and its metabolites
Authors: Wright Patricia , Alex Alexander , Nyaruwata Tsitsi , Parsons Teresa , Pullen Frank
Published: March 2010

Tandem mass spectrometry (MS/MS) is widely used for the identification of metabolites at all stages of the pharmaceutical discovery and development process. The assignment of ions in the product ion spectra can be time‐consuming and hence delay feedback of results that may influence the direction of a project. A deeper understanding of the processes involved in generation of the product ions formed via collision‐induced dissociation may allow development of chemically intelligent software to aid spectral interpretation. Current commercially available spectral interpretation software takes a mainly arithmetical approach resulting in extensive lists of numerically plausible ions, many of which may not be chemically feasible. In this study, high‐resolution MS/MS spectra were obtained for maraviroc and two of its synthetic metabolites, and structures for the product ions proposed. Density functional theory (DFT) based on in silico modelling was undertaken to investigate whether the fragmentation observed was potentially a result of bond lengthening (and hence weakening) as a consequence of protonation of the molecule at the most thermodynamically stable site(s). It was determined that for all three compounds, where the product ions resulted from simple bond cleavages (not rearrangements), the bonds that cleaved had been calculated to elongate after protonation. It was also noted that the protonated molecule may represent a mixture of singly charged protonated species and that the most basic sites in the molecule may not necessarily be the most thermodynamically stable for protonation. Copyright © 2010 John Wiley & Sons, Ltd.