bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular epidemiology of carbapenem‐resistant Acinetobacter spp. from XiangYa Hospital, in Hunan Province, China
Authors: Chen Zhenhua , Liu Wenen , Zhang Yunli , Li Yanbing , Jian Zijuan , Deng Hongli , Zou Mingxiang , Liu Yuanyuan
Published: May 2012

Carbapenem‐resistant Acinetobacter baumannii has been known as an opportunistic pathogen that causes a variety of illness worldwide. In this study, we characterize the molecular epidemiology of 174 non‐repetitive clinical isolates of A. baumannii collected from January to June 2009 from Xiangya Hospital, in Hunan Province, China, including an outbreak period of A. baumannii. These 174 isolates harbored A. baumannii intrinsic gene OXA‐51. They were resistant to multiple antibiotics with resistance rates as 49.4% to imipenem, 48.3% to meropenem, 46.6% to ampicillin‐sulbactam, 6.9% to cefoperazone‐sulbactam, and 6.3% to minocycline. 74 out of 174 isolates were identified as carbapenemase‐producing strains, among which blaOXA‐23 gene was found in 71 isolates. These 74 carbapenemase expression strains could be divided into four genotypes by enterobacterial repetitive intergenic consensus (ERIC)‐PCR, with 19, 17, 33 and 5 clones in each group. We also found four imipenem resistant isolates carrying OXA‐23 gene without showing carbapenemase phenotype. Our findings show that the blaOXA‐23 gene is the common carbapenemase gene among carbapenem‐resistant Acinetobacter spp. isolates, suggesting that clonal spread of carbapenemase‐producing isolates may be one important factor which results in the high carbapenem resistance rate in the local hospital in Hunan Province, China.
The expression of LytM is down‐regulated by RNAIII in Staphylococcus aureus
Authors: Chunhua Mu , Yu Liu , Yaping Gao , Jie Dong , Qiang Lu , Xiaorong Tan , Guang Yang
Published: May 2012

LytM is one kind of autolysin expressed in Staphylococcus aureus. It can hydrolyze peptide bond of pentaglycine, which is the component of cell wall. Until now, the regulation on the expression of LytM is still unclear. Here, we found that the level of LytM in the RNAIII mutant was increased. RNAIII is an important small regulatory RNA in S. aureus. Our further investigation revealed that RNAIII can interact with the 5′UTR of lytM mRNA and block the ribosome binding sites [RBS]. So our results identified that LytM was the new target of RNAIII. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Glucose released by hydrolytic activity of amylase influences the pigment synthesis in Penicillium sp NIOM‐02
Authors: Puttananjaiah Mohan‐Kumari H. , Dhale Mohan A.
Published: May 2012

Carbon catabolite repression is generally considered as a regulatory mechanism to ensure sequential synthesis of secondary metabolites. In this study we made an attempt to understand the influence of amylase activity on pigment synthesis in Penicillium sp NIOM‐02. The amylase activity is inversely proportional to pigment production. The high performance liquid chromatography analysis of amylase reaction revealed glucose as the major product of starch hydrolysis. The fungus grown in acarbose (inhibitor of amylase) incorporated media produced higher quantities of pigments. Apparently, glucose released due to amylase activity influenced the pigment synthesis by cAMP signaling pathway.
Genotypic intraspecies heterogeneity of Enterococcus italicus: data from dairy environments
Authors: Borgo Francesca , Ferrario Chiara , Ricci Giovanni , Fortina Maria Grazia
Published: May 2012

The diversity of a collection of 19 Enterococcus italicus strains isolated from different dairy sources was explored using a molecular polyphasic approach, comprising random amplification of polymorphic DNA (RAPD‐PCR), repetitive element PCR (REP‐PCR), plasmid profiling and ribotyping. The data obtained showed a high‐level of biodiversity, not always correlated to the niche of isolation. Particularly, REP‐PCR with primer BOXA1R and plasmid profiling allowed the best discrimination at strain level. Exploiting the genome shotgun sequence of the type strain of the species, available in public database, genes related to insertion sequences present on enterococcal Pathogenic Islands (ISEf1, IS905), determinants related to virulence factors (codifying for hemolysin and cell wall surface proteins), exogenously DNA (conjugal transfer protein, replication plasmid protein, pheromone shutdown protein, phage integrase/recombinase) and penicillin binding proteins system were detected. The presence of most of these genes seemed a common genetic trait in the Enterococcus genus, sur gene (cell wall surface protein) was only detected in strains of E. italicus. To our knowledge, this is the first time that specific primers, with the expection of the species‐specific probe targeted to 16S rRNA gene, have been designed for this species.
Characterization of the microbial diversity in production waters of mesothermic and geothermic Tunisian oilfields
Authors: Mnif Sami , Bru‐Adan Valérie , Godon Jean‐Jacques , Sayadi Sami , Chamkha Mohamed
Published: May 2012

The microbial diversity of production waters of five Tunisian oilfields was investigated using Single Strand Conformation Polymorphism (SSCP) technique followed by cloning‐sequencing. Dynamics of bacterial populations in production waters collected from four wellheads were also evaluated. For all production water samples collected, DNA from Archaea and Eucarya was not sufficiently abundant to permit detection rRNA genes from these groups by PCR‐SSCP. In contrast, the bacterial rRNA genes were detected in all samples, except for samples from DOULEB12 and RAMOURA wells. SSCP profiles attested that two of the studied geothermic wells (ASHTART47 and ASHTART48) had shown a clear change over time, whereas a stable diversity was found with the mesophilic DOULEB well (DL3). PCR amplification of rRNA genes was unsuccessful with samples from DOULEB (DL12) at all three sampling time. The bacterial diversity present in production waters collected from pipelines of SERCINA and LITAYEM oilfields was high, while production waters collected from wellheads (ASHTART and DOULEB) exhibited lower diversity. The partial study of the biodiversity showed a dominance of uncultured bacteria and Pseudomonas genus (class of the Gammaproteobacteria) in three of the studied oilfields (ASHTART47, ASHTART48 and DOULEB3). However, for LITAYEM oilfield, a significant dominance of 5 phyla (Proteobacteria, Thermotogae, Firmicutes, Synergistetes, Bacteroidetes) was shown. Our study gives a real picture of the microbiology of some Tunisian oilfield production waters and shows that some of the sequenced bacterial clones have a great similarity to previous sequenced clones described from other oilfields all over the world, indicating that these ecosystems harbour specific microbial communities. These findings can be considered as an indirect indication of the indigenous origin of these clones.
An efficient protocol for isolating melanised chaetothyrialean anamorphic fungi associated with plant‐ants
Authors: Ruiz‐González Mario X. , Lauth Jérémie , Leroy Céline , Jauneau Alain , Gryta Hervé , Jargeat Patricia , Dejean Alain , Orivel Jérôme
Published: May 2012

Because of their ecological characteristics, slow growth rates and the presence of contaminants, Chaetothyriales fungi associated with structures built by tropical plant‐ants can be difficult to isolate with standard procedures. Here, we describe an easy‐to‐use protocol for obtaining pure cultures by using cotton as a first substrate. We have further found by means of fluorescent stains that nuclei concentrate either in young hyphae or in the tips of the hyphae.
Impact of esophageal invasion on clinicopathological characteristics and long‐term outcome of adenocarcinoma of the subcardia
Authors: Tokunaga Masanori , Tanizawa Yutaka , Bando Etsuro , Kawamura Taiichi , Tsubosa Yasuhiro , Terashima Masanori
Published: May 2012

Backgrounds and Objectives

A different classification system was used in the 7th edition of the TNM classification for adenocarcinoma of the subcardia either with or without esophageal invasion. The aim of this study was to clarify the clinicopathological and survival impact of esophageal invasion.

Methods

The present study included 351 patients who underwent gastrectomy for adenocarcinoma located within 5 cm of the esophagogastric junction. The clinicopathological characteristics and survival curves were compared between patients with esophageal invasion [E (+) group, n = 125] and without esophageal invasion [E (−) group, n = 226].

Results

Patients in the E (+) group had more advanced disease. The 5‐year survival rate following macroscopic curative resection was significantly better in the E (−) group (80.8%) than in the E (+) (48.7%, P < 0.001), even after stratification by the pathological stage and nodal status. Multivariate analysis identified esophageal invasion (hazard ratio; 3.323, 95% confidential interval; 1.815–6.082) as one of the independent prognostic factors.

Conclusions

Esophageal invasion affected the clinicopathological characteristics and long‐term outcome of patients. Further study is necessary to clarify whether patients with esophageal invasion should be classified using the system for esophageal cancer or by another method. J. Surg. Oncol. 2012; 106:856–861. © 2012 Wiley Periodicals, Inc.
The correlations between the expression of FGFR4 protein and clinicopathological parameters as well as prognosis of gastric cancer patients
Authors: Ye Yan‐Wei , Zhang Xiefu , Zhou Ye , Wu Jianghong , Zhao Chunlin , Yuan Lin , Wang Guojun , Du Chunyan , Wang Chunmeng , Shi Yingqiang
Published: May 2012

Background

Fibroblast growth factor receptor 4 (FGFR4) was seldom investigated in gastric cancer (GC). The purpose of the study was to elucidate the expression of FGFR4 protein in GC and related clinical significance.

Methods

Ninety‐four paraffin‐embedded tumor specimens were obtained from Cancer Hospital, Fudan University. The expression of FGFR4 as well as p53, p21, EGFR, neu, c‐myc, and PCNA were detected by immunohistochemical method. Then, correlation analysis and survival analysis were performed.

Results

The expression rate of FGFR4 protein in GC tissues and normal stomach tissues was 93.6% and 30.8%, respectively (P = 0.000). The expression of FGFR4 was positively correlated with the expression of p21, neu and PCNA (P‐value was 0.009, 0.012, and 0.018, respectively). Subgroup analysis showed that compared to low expression group, the prognosis of patients with III/IV stage and negative expression of p21 in high expression group of FGFR4 were worse (P = 0.048, 0.041, respectively). Multivariate analysis showed that TNM stage was the independent prognostic factor in high expression group (HR, 11.593; 95% CI, 3.532–18.058;P = 0.000).

Conclusions

High expression of FGFR4 protein, accelerating the progression of advanced GC, might be associated with a poor prognosis in patients with advanced FC. J. Surg. Oncol. 2012; 106:872–879. © 2012 Wiley Periodicals, Inc.
From Producer to Purchaser of IT Services: interactional Knowledge
Authors: Yakhlef Ali , Sié Laurent
Published: May 2012

Several researchers have sought to establish the drivers behind and effects of outsourcing on organizations (nations and economies at large). Less research, however, has concerned itself with the changing role that firms go through—from a producer of information technology services to a purchaser of those services—and the form of knowledge that this new role requires. The present paper describes this process of going from consumer to purchaser of information technology services, focusing on the form of knowledge that emerges in this process. As an illustration, the paper draws on case study material gleaned from four firms that have outsourced parts or all of their information technology activities. Becoming a purchaser, it is found, presupposes the development of “interactional knowledge”. Interactional knowledge or expertise involves a new language related to standardized monitoring performance and quality measurements, detailed contracts in the form of service level agreements—all of which facilitate communication, enable exchange, reduce transaction costs, and give birth to a new market. Several questions concerning the effects of outsourcing on firms can be revisited, and new research directions are suggested. Copyright © 2012 John Wiley & Sons, Ltd.
In vivo O‐Space imaging with a dedicated 12 cm Z2 insert coil on a human 3T scanner using phase map calibration
Authors: Stockmann Jason P. , Galiana Gigi , Tam Leo , Juchem Christoph , Nixon Terence W. , Constable R. Todd
Published: May 2012

Recently, spatial encoding with nonlinear magnetic fields has drawn attention for its potential to achieve faster gradient switching within safety limits, tailored resolution in regions of interest, and improved parallel imaging using encoding fields that complement the sensitivity profiles of radio frequency receive arrays. Proposed methods can broadly be divided into those that use phase encoding (Cartesian‐trajectory PatLoc and COGNAC) and those that acquire nonlinear projections (O‐Space, Null space imaging, radial PatLoc, and 4D‐RIO). Nonlinear projection data are most often reconstructed with iterative algorithms that backproject data using the full encoding matrix. Just like conventional radial sequences that use linear spatial encoding magnetic fields, nonlinear projection methods are more sensitive than phase encoding methods to imperfect calibration of the encoding fields. In this work, voxel‐wise phase evolution is mapped at each acquired point in an O‐Space trajectory using a variant of chemical shift imaging, capturing all spin dynamics caused by encoding fields, eddy currents, and pulse timing. Phase map calibration is then applied to data acquired from a high‐power, 12 cm, Z2 insert coil with an eight‐channel radio frequency transmit‐receive array on a 3T human scanner. We show the first experimental proof‐of‐concept O‐Space images on in vivo and phantom samples, paving the way for more in‐depth exploration of O‐Space and similar imaging methods. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Three New Natural Compounds from the Root Bark Essential Oil from Xylopia aethiopica
Authors: Yapi Thierry Acafou , Boti Jean Brice , Attioua Barthelemy Koffi , Ahibo Antoine Coffy , Bighelli Ange , Casanova Joseph , Tomi Félix
Published: May 2012

Introduction

In the course of on‐going work on the characterisation of aromatic plants from the Ivory Coast we investigated the composition of the root oil from Xylopia aethiopica.

Objectives

The aim of this work was to investigate the chemical composition of X. aethiopica root oil and elucidate the structure of two new compounds.

Methodology

Analysis of the essential oil was carried out using a combination of chromatographic (CC, GC with retention indices) and spectroscopic techniques (MS, 13C‐NMR, 2D‐NMR).

Results

Twenty seven components, accounting for 95.6% of the whole composition, were identified including various compounds for which spectroscopic data were absent on commercial computerised MS libraries. Three compounds are reported for the first time as natural compounds and the structure of two new compounds, 4,4‐dimethyl‐2‐vinylcyclohexene and endo‐5‐methoxy‐3‐patchoulene, has been elucidated using extensive two‐dimensional NMR spectroscopy.

Conclusion

The composition of X. aethiopica root oil is dominated by two dimethylvinylcyclohexene isomers. It differs drastically from the composition of leaf and fruit oils of the same plant. The combination of analytical techniques appeared crucial for a fruitful analysis. Copyright © 2012 John Wiley & Sons, Ltd.
One‐step Preparative Separation of Two Polyhydroxystilbenes from Rheum likiangense Sam. by High‐speed Counter‐current Chromatography
Authors: Wang Xiaoyan , Wang Honglun , Ding Chenxu , Suo Yourui
Published: May 2012

Introduction

The official rhubarb species have frequently been investigated for their hydroxyanthraquinone components and associated pharmacological properties. However, other unofficial rhubarb species were rarely studied until polyhydroxystilbenes (PHS), which commonly occur in the unofficial rhubarb, revealed a range of potential bioactivities. Hence, there has been increasing interest in the efficient preparation of high‐purity PHS for pharmacological and clinical trials.

Objective

To develop a suitable method for large‐scale preparative separation of PHS from the rhizome of Rheum likiangense Sam. by high‐speed counter‐current chromatography (HSCCC).

Results

Two PHS compounds were isolated successfully within 440 min using a solvent system consisting of methanol:n‐butanol:chloroform:water (2:0.5:3:3, v/v/v/v). Eighty‐four milligrams of desoxyrhaponticin with 98.2% purity and 148 mg of rhaponticin with 95.3% purity were respectively yielded from 1.5 g of crude extract in the single, one‐step operation.

Conclusion

An optimised HSCCC method has been established for large‐scale preparative separation of PHS compounds from Rheum likiangense Sam. Copyright © 2012 John Wiley & Sons, Ltd.
DNA sequencing of maternal plasma to identify Down syndrome and other trisomies in multiple gestations
Authors: Canick Jacob A. , Kloza Edward M. , Lambert‐Messerlian Geralyn M. , Haddow James E. , Ehrich Mathias , van den Boom Dirk , Bombard Allan T. , Deciu Cosmin , Palomaki Glenn E.
Published: May 2012

Objective

Studies on prenatal testing for Down syndrome (trisomy 21), trisomy 18, and trisomy 13 by massively parallel shotgun sequencing (MPSS) of circulating cell free DNA have been, for the most part, limited to singleton pregnancies. If MPSS testing is offered clinically, it is important to know if these trisomies will also be identified in multiple pregnancies.

Method

Among a cohort of 4664 high‐risk pregnancies, maternal plasma samples were tested from 25 twin pregnancies (17 euploid, five discordant and two concordant for Down syndrome; one discordant for trisomy 13) and two euploid triplet pregnancies [Correction made here after initial online publication.]. Results were corrected for GC content bias. For each target chromosome (21, 18, and 13), z‐scores of 3 or higher were considered consistent with trisomy.

Results

Seven twin pregnancies with Down syndrome, one with trisomy 13, and all 17 twin euploid pregnancies were correctly classified [detection rate 100%, 95% confidence interval (CI) 59%–100%, false positive rate 0%, 95% CI 0%–19.5%], as were the two triplet euploid pregnancies.

Conclusion

Although study size is limited, the underlying biology combined with the present data provide evidence that MPSS testing can be reliably used as a secondary screening test for Down syndrome in women with high‐risk twin gestations. © 2012 John Wiley & Sons, Ltd.
Is fetal magnetic resonance imaging indicated when ultrasound isolated mild ventriculomegaly is present in pregnancies with no risk factors?
Authors: Parazzini Cecilia , Righini Andrea , Doneda Chiara , Arrigoni Filippo , Rustico Mariangela , Lanna Mariano , Triulzi Fabio
Published: May 2012

Objective

Ventriculomegaly (VM) is the most common brain anomaly in prenatal ultrasound (US) diagnosis. There is a general trend to perform fetal magnetic resonance imaging (MRI) when VM is severe (greater than 15 mm) and/or it is not isolated. The role of MRI is debated when VM is borderline (between 10 and 15 mm) and isolated. Some authors have subdivided borderline VM into mild (10 to 12 mm) and moderate (>12 to15 mm). The aim of the study was to evaluate the role of MR in the imaging protocol of fetal cases characterized by mild isolated VM and no risk factors.

Method

As a retrospective study, 179 fetal MRI exams (mean gestational age: 26 weeks), performed for mild, isolated VM on US, were analyzed to search additional or different findings with respect to ultrasound. The potential impact of MRI results on prenatal counselling is described.

Results

In 49/179 cases, MRI and US results differed, but only in two of these cases did MRI studies provide clinically consistent additional information. In 130/179 cases, MRI confirmed US findings.

Conclusion

In this extremely selected group of fetuses with isolated, mild VM and no risk factors, MRI may not be indicated in the prenatal imaging protocol. © 2012 John Wiley & Sons, Ltd.
Trends in antihypertensives use among Moroccan patients
Authors: Berrada El Azizi G. , Ahid S. , Ghanname I. , Belaiche A. , Hassar M. , Cherrah Y.
Published: May 2012

Purpose

In this study, we analyzed the consumption trends of antihypertensives in Morocco during the 1991–2010 period and the impacts after the institution of Mandatory Health Insurance and the marketing of generic drugs.

Methods

We used sales data from the Moroccan subsidiary of IMS Health “Intercontinental Marketing Service”. The consumption volumes were converted into defined daily doses (DDDs).

Results

Between 1991 and 2010, outpatient consumption of antihypertensives went from 4.37 to 23.14 DDD/1000 inhabitants/day, a 5.30‐fold increase. In 2010, calcium channel blockers (CCBs) and angiotensin converting enzyme inhibitors (ACEI) were the most consumed (4.97 DDD/1000 inhabitants/day) for each one, followed by diuretics (4.20 DDD/1000 inhabitants/day). The most consumed products were amlodipine (4.27 DDD/1000 inhabitants/day) followed by ramipril (3.18 DDD/1000 inhabitants /day) and indapamide (1.72 DDD/1000inhabitants/day). Between 1991 and 2010, the consumption of generic antihypertensives went from 2% to 46%.

Conclusion

Antihypertensive consumption increased between 1991 and 2010. However, despite the increase of generic drugs consumption, the levels of antihypertensive consumption remain lower than the needs of hypertensive patients. Copyright © 2012 John Wiley & Sons, Ltd.
New, organo‐soluble, thermally stable aromatic polyimides and poly(amide‐imide) based on 2‐[5‐(3,5‐dinitrophenyl)‐1,3, 4‐oxadiazole‐2‐yl]pyridine
Authors: Mansoori Yagoub , Atghia Seyed Vahid , Sanaei Somyeh Shah , Zamanloo Mohammad Reza , Imanzadeh Gholamhassan , Eskandari Habibollah
Published: May 2012

New, thermally stable polyimides and a poly(amide‐imide) containing a 1,3,4‐oxadiazole‐2‐pyridyl pendant group based on 2‐[5‐(3,5‐diaminophenyl)‐1,3,4‐oxadiazole‐2‐yl]pyridine were synthesized. The synthesis and characterization of the model compound 2‐{5‐[(3,5‐bistrimellitimido)phenyl]‐1,3,4‐oxadiazole‐2‐yl}pyridine (DIDA) were also investigated, and DIDA was used in the preparation of the poly(amide‐imide) in an ionic liquid, 1‐butyl‐3‐methylimidazolium bromide, as a polymerization solvent. The polymers were characterized by separating and characterizing the poly(amic acid) intermediates using infrared and elemental analyses. The prepared polymers were soluble in polar and aprotic solvents, such as dimethylformamide, dimethylsulfoxide, N‐methyl‐2‐pyrrolidone and dimethylacetamide. Thermal behaviour of the polymers was studied using thermogravimetric analysis and differential scanning calorimetry. The inherent viscosities of the polyimide and poly(amide‐imide) solutions were in the range 0.34–0.85 dL g−1 (in concentrated sulfuric acid with a concentration of 0.125 g dL−1 at 25 ± 0.5 °C). The removal of Co(II) from aqueous solutions was performed using one of the polyimides. It was found that this polymer had a maximum adsorption capacity and efficiency at pH = 10.0. Copyright © 2012 Society of Chemical Industry
Exploring Negotiation through Boundary Objects in Global Design Project Networks
Authors: Di Marco Melissa K. , Alin Pauli , Taylor John E.
Published: May 2012

Boundary objects have been shown to play an important role in sharing knowledge in and across firms. However, little research has examined whether boundary objects can facilitate emergence of common knowledge across national cultural boundaries. To examine this, we observed 1,428 design review interactions involving U.S. and Indian engineers. We quantitatively analyzed 419 interactions involving engineers and boundary objects and then qualitatively analyzed 67 instances of boundary object–mediated negotiation. We found that boundary objects can play a central role in negotiating complex design knowledge. We then induced a propositional theoretical model of boundary object–mediated negotiation in global design project networks.
Synthesis and characterization of original alternated fluorinated copolymers bearing glycidyl carbonate side groups
Authors: Alaaeddine Ali , Boschet Frédéric , Ameduri Bruno , Boutevin Bernard
Published: May 2012

A vinyl ether bearing a carbonate side group (2‐oxo‐1,3‐dioxolan‐4‐yl‐methyl vinyl ether, GCVE) was synthesized and copolymerized with various commercially available fluoroolefins [chlorotrifluoroethylene (CTFE), hexafluoropropylene (HFP), and perfluoromethyl vinyl ether (PMVE)] by radical copolymerization initiated by tert‐butyl peroxypivalate. Although HFP, PMVE, and vinyl ether do not homopolymerize under radical conditions, they copolymerized easily yielding alternating poly(GCVE‐alt‐F‐alkene) copolymers. These alternating structures were confirmed by elemental analysis as well as 1H, 19F, and 13C NMR spectroscopy. All copolymers were obtained in good yield (73–85%), with molecular weights ranging from 3900 to 4600 g mol−1 and polydispersities below 2.0. Their thermogravimetric analyses under air showed decomposition temperatures at 10% weight loss (Td,10%) in the 284–330°C range. The HFP‐based copolymer exhibited a better thermal stability than those based on CTFE and PMVE. The glass transition temperatures were in the 15–65°C range. These original copolymers may find potential interest as polymer electrolytes in lithium ions batteries. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Cyclodextrin functionalization: Simple routes to tailored solubilities and nanoscopic polymer networks
Authors: Gyanwali Gaumani , Hodge Mathis , White Jeffery L.
Published: May 2012

The systematic chemical modification of cyclodextrins (CDs) provides an opportunity to create new substances with novel phase transfer, guest–host, solubility, and network properties. Such materials have several potential applications in polymer science, including free‐volume modifiers, stabilizers or compatibilizers, and scaffolds or templates for synthesizing new materials. In this study, we describe simple, inexpensive, and easy purification one‐pot methods to selectively functionalize CD rings with short‐ and long‐chain alkyl derivatives of varying polarity. Using bifunctional reagents in the same reaction scheme yields CD‐based polymer networks. Particular attention is devoted to solution and solid‐state NMR experiments that reveal the type and extent of functionalization, which may be used to control solubility and swelling. Alkyl chain functionalization may be expressed as the average number of CH2 units attached per CD ring, the magnitude of which can reach at least 16 and the product still be water soluble, but products become insoluble in water at a value of 32. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Influencing the phase transition temperature of poly(methoxy diethylene glycol acrylate) by molar mass, end groups, and polymer architecture
Authors: Miasnikova Anna , Laschewsky André
Published: May 2012

The easily accessible, but virtually overlooked monomer methoxy diethylene glycol acrylate was polymerized by the RAFT method using monofunctional, difunctional, and trifunctional trithiocarbonates to afford thermoresponsive polymers exhibiting lower critical solution temperature‐type phase transitions in aqueous solution. The use of the appropriate RAFT agent allowed for the preparation and systematic variation of polymers with defined molar mass, end‐groups, and architecture, including amphiphilic diblock, symmetrical triblock, and triarm star‐block copolymers, containing polystyrene as permanently hydrophobic constituent. The cloud points (CPs) of the various polymers proved to be sensitive to all varied parameters, namely molar mass, nature, and number of the end‐groups, and the architecture, up to relatively high molar masses. Thus, CPs of the polymers can be adjusted within the physiological interesting range of 20–40 °C. Remarkably, CPs increased with the molar mass, even when hydrophilic end groups were attached to the polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Reactive polythiophenes with zincke salt structure: Synthesis, polymer reactions, and chemical properties
Authors: Yamaguchi Isao , Nakahara Takuya
Published: May 2012

Polythiophenes with reactive Zincke salt structure, such as PThThPy+DNP(Cl−)Th, were synthesized by the oxidation polymerization of 3′‐(4‐N‐(2,4‐dinitrophenyl)pyridinium chloride)‐2,2′:5′,2″‐terthiophene (ThThPy+DNP(Cl−)Th) with iron(III) chloride or copper(II) trifluoromethanesulfonate. The reaction of PThThPy+DNP(Cl−)Th with R‐NH2 (R = n‐hexyl (Hex) and phenyl (Ph)) substituted the 2,4‐dinitrophenyl group into the R group with the elimination of 2,4‐dinitroaniline to yield PThThPy+R(Cl−)Th. Similarly, model compounds, ThThPy+R(Cl−)Th (R = Hex and Ph), were also synthesized. In contrast to the photoluminescent ThThPyTh and PThThPyTh, the compounds PThThPy+DNP(Cl−)Th, PThThPy+R(Cl−)Th, and ThThPy+R(Cl−)Th showed no photoluminescence because their internal pyridinium rings acted as quenchers. Cyclic voltammetry measurements suggested that PThThPy+DNP(Cl−)Th received an electrochemical reduction of the pyridinium and 2,4‐dinitrophenyl groups and oxidation of the polymer backbone. PThThPy+DNP(Cl−)Th was electrically conductive (ρ = 2.0 × 10−6 S cm−1) in the non‐doped state. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Multilayered polycarbonate/poly(vinylidene fluoride‐co‐hexafluoropropylene) for high energy density capacitors with enhanced lifetime
Authors: Zhou Zheng , Mackey Matt , Carr Joel , Zhu Lei , Flandin Lionel , Baer Eric
Published: May 2012

The dielectric lifetime and corresponding damage morphology of polycarbonate/poly(vinylidene fluoride‐co‐hexafluoropropylene) (PC/P(VDF‐HFP)) layered systems are studied under constant direct current (DC) field. Melt blends of the two polymers are also considered for comparison. The dielectric lifetimes of the latter are systematically much shorter than the layered systems. The interfaces between the polymers act as flaws that induce up to two orders of magnitude difference between the layered and blend systems. The capacitance values versus time during breakdown progression exhibit an inversed S‐shape pattern. The three regimes in the S‐shape pattern are consecutively attributed to randomly isolated breakdowns, interconnecting breakdowns, and wearing‐out of the capacitor film. The film breakdown images during dielectric lifetime test confirmed the transition from randomly isolated breakdowns to interconnecting breakdowns. This transition was further evidenced by a bimodal distribution in the Weibull analysis. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Structural analysis of poly(amidoamine) dendrimer immobilized in crosslinked poly(ethylene glycol)
Authors: Taniguchi Ikuo , Kazama Shingo , Jinnai Hiroshi
Published: May 2012

Polymeric membranes comprised of poly(amidoamine) (PAMAM) dendrimer immobilized in a poly(ethylene glycol) (PEG) network exhibit an excellent CO2 separation selectivity over H2. The CO2 permeability increases with PAMAM dendrimer concentration in the polymeric membrane and becomes 500 times greater than H2 permeability when the dendrimer content was 50 wt % at ambient conditions (5 kPa of CO2 partial pressure). However, the detailed morphology of the membrane has not been discussed. The immiscibility of PAMAM dendrimer and PEG matrix results in phase separation, which takes place in a couple of microns scale. Especially, laser scanning confocal microscope captures a 3D morphology of the polymeric blend. The obtained 3D reconstructions demonstrate a bicontinuous structure of PAMAM dendrimer‐rich and PEG‐rich phases, which indicates the presence of PAMAM dendrimer channel penetrating the polymeric membrane, and CO2 will preferentially pass through the dendrimer channel. In addition, Fourier transform of the 3D reconstructions indicates the presence of a periodic structure. An average size of the dendrimer domain calculated is 2–4 μm in proportion to PAMAM dendrimer concentration. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Enhancing patient participation in oncology consultations: a best evidence synthesis of patient‐targeted interventions
Authors: Henselmans Inge , de Haes Hanneke C. J. M. , Smets Ellen M. A.
Published: May 2012

Objective

Because of the complexity of cancer consultations, the contribution of patients is often limited. This systematic review examined the characteristics and effectiveness of patient‐targeted interventions that aim to enhance cancer patients' participation in the consultation.

Methods

Relevant studies were selected by a search of databases until mid‐2010 (Pubmed, PsycINFO and CINAHL), citations in relevant reviews as well as backward/forward citations. A Best Evidence Synthesis was performed, taking into account the quality of studies.

Results

A total of 52 publications were included, describing 46 studies and 30 unique interventions. One‐third was delivered through either written or multimedia material, two‐thirds face to face. Most originated from English‐speaking countries. Half targeted heterogeneous cancer populations, one‐third targeted women with breast cancer. Half focussed on initial treatment‐planning consultations. Overall, there was evidence for an effect on observed patient participation. There was no evidence for an effect on patient or doctor satisfaction and insufficient evidence for an effect on psychological well‐being, physical well‐being and consultation duration. The findings turned out to be largely independent of study quality.

Conclusions

Effect of the interventions could only be demonstrated for immediate outcomes, that is, behaviour observed in the consultation. Implications for future research are discussed, including attention for gaps in the literature as well as the choice of outcome measures. Copyright © 2012 John Wiley & Sons, Ltd.
Use of PCA3 in detecting prostate cancer in initial and repeat prostate biopsy patients
Authors: Goode Roland R. , Marshall Susan J. , Duff Michael , Chevli Eric , Chevli K. Kent
Published: May 2012

BACKGROUND

The PCA3 urinary assay has shown promise in predicting the presence of prostate cancer. We evaluated the value of this test in patients undergoing initial and repeat prostate biopsy.

METHODS

PCA3 and PSA levels were obtained from 456 men with no known personal history of prostate cancer prior to prostate biopsy. Two hundred eighty‐nine men underwent an initial prostate biopsy and 167 underwent a repeat prostate biopsy. PCA3 and PSA levels were compared to the prostate biopsy results.

RESULTS

PCA3 score was shown to be independent of prostate volume (P = 0.162) and PSA level (P = 0.959). PCA3 scores were significantly higher in patients with cancer on prostate biopsy compared to patients with negative biopsy results (P < 0.0001). In logistic regression, PCA3 showed a significantly higher AUC than PSA (0.726 vs. 0.512, P = 0.0001). This difference persisted when examining the initial biopsy subgroup, with PCA3 out‐performing PSA (AUC 0.772 vs. AUC = 0.552, P < 0.0001), but not in the repeat biopsy subgroup (AUC = 0.605 vs. AUC = 0.500, P = 0.2488).

CONCLUSIONS

PCA3 was found to be a better predictor of prostate cancer than PSA in the total population as well as the initial biopsy population, but was not superior to PSA in the repeat biopsy population. Prostate 73: 48–53, 2013. © 2012 Wiley Periodicals, Inc.
Backside‐electrode effects on current collapse in field‐plate AlGaN/GaN HEMTs
Authors: Horio Kazushige , Onodera Hiraku
Published: May 2012

Two‐dimensional transient analysis of field‐plate AlGaN/GaN HEMTs with a backside electrode is performed by considering the use of a deep donor and a deep acceptor in a buffer layer. Effects of introducing the field plate and backside electrode on buffer‐related current collapse are studied. It is shown that the introduction of field plate is effective in reducing current collapse when the acceptor density in the buffer layer is high. On the other hand, the introduction of backside electrode is shown to be effective in reducing current collapse when the acceptor density in the buffer layer is relatively low, because the fixed potential at the backside electrode reduces electron injection into the buffer layer and the resulting trapping effects (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Radiation hardness of single‐crystalline zinc oxide films
Authors: Koike Kazuto , Aoki Takahiro , Fujimoto Ryugo , Sasa Shigehiko , Yano Mitsuaki , Gonda Shun‐ichi , Ishigami Ryoya , Kume Kyo
Published: May 2012

Zinc oxide (ZnO) is a potential semiconductor to exhibit high radiation hardness since large threshold displacement energy for damage can be expected due to the small unit‐cell volume and large bandgap energy. In order to study the radiation hardness, single‐crystalline c‐axis‐oriented ZnO films with and without two‐dimensional electron gas, and bulk crystals of ZnO and gallium nitride (GaN) for comparison, were irradiated with 8 MeV protons at the wide range of fluences from 2×1013 to 1×1017 p/cm2. For both ZnO films, decrease of luminescence intensity followed by increase of electrical resistance was observed at larger fluences than ∼5×1014 p/cm2. This threshold fluence was found to be much larger and larger than those of GaN and ZnO bulk crystals, respectively, indicating that ZnO thin films should be useful for such device applications as the electronics for space satellites and nuclear reactors. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural studies of GaN1‐x Asx and GaN1‐x Bix alloys for solar cell applications
Authors: Liliental‐Weber Z. , dos Reis R. , Levander A. X. , Yu K. M. , Walukiewicz W. , Novikov S. V. , Foxon C. T.
Published: May 2012

We have discovered materials with a wide tunability of the band gap that opens the possibility to achieve a desirable material for multi‐junction solar cells. Two different alloy systems have been studied. GaN1‐xAsx alloys over the entire composition range were grown by plasma‐assisted MBE at low temperature on crystalline and amorphous (glass) substrates. For growth on sapphire the alloys are amorphous in the composition range of 0.17<x<0.75, but for growth on glass the composition range for amorphous alloys extends to x∼0.1. The bandgap of the GaN1‐xAsx alloys ranges from 3.4‐0.7 eV, covering a large part of the solar spectrum, therefore this material is potentially useful for solar energy conversion.

The substitution of N by Bi in GaN forming GaN1‐x Bix is extremely difficult since Bi and N have even larger differences in size and electronegativity. TEM studies of GaN1‐xBix with x up to 0.2 show that the alloy is not entirely amorphous. Small crystallites embedded in an amorphous matrix are observed and Bi segregation was confirmed by Electron Energy Loss studies. A strong reduction in band gap is observed in samples with increasing Bi, suggesting the formation of a random alloy but low energy absorption tail may be related to the presence of the crystallites observed by TEM (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence properties of Ag‐, Ga‐doped ZnO and ZnO‐ZnS thin films
Authors: Kushnirenko V. I. , Khomchenko V. S. , Zashivailo T. V. , Zavyalova L. V.
Published: May 2012

Thin films of ZnS were grown by metal‐organic chemical vapor deposition (MOCVD) method under atmospheric pressure onto glass substrates. ZnO–ZnS:[Ag, Ga] and ZnO:[Ag, Ga] thin films were prepared by oxidation and Ag, Ga doping of ZnS films at temperatures of 700–775 °C for 0.5–1 h. Crystalline quality and luminescent properties were investigated using X‐ray diffraction (XRD), atomic force microscopy (AFM), and photoluminescence. It is found that the doped films have a polycrystalline structure without preferred orientation and consist of small grains gathered into conglomerates. The shape of photoluminescence (PL) spectra of the films depends strongly on the preparation conditions. The ZnO–ZnS:[Ag, Ga] films exhibited the blue and green emission connected with the presence of silver and oxygen, respectively. The ZnO:[Ag, Ga] films revealed the white emission originated from different defect‐related transitions. The possible origin of radiative centers is discussed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Metalorganic vapor phase epitaxial growth of (211)B CdTe on nanopatterned (211)Si
Authors: Shintri Shashidhar , Rao Sunil , Schaper Charles , Palosz Witold , Trivedi Sudhir , Semendy Fred , Wijewarnasuriya Priyalal , Bhat Ishwara
Published: May 2012

Low‐defect density epitaxial CdTe on Si is very crucial for fabricating high performance HgCdTe IR focal planar arrays on Si. This paper discusses a novel nanopatterning technique to explore defect reduction in CdTe epitaxy on (211)Si. Nanopatterning of full 3″ (211)Si wafers was done by growing a thin layer of thermal SiO2 and patterning by molecular transfer lithography (MxL) based on water‐soluble templates. Conditions for obtaining selective Ge and CdTe were obtained in the temperature range of 575‐675 °C and 505‐520 °C respectively. X‐ray analysis of thin CdTe films grown on these substrates gave wider full‐width half‐maximum (FWHM) values when compared to the layers grown on blanket (non‐patterned) (211)Si, which is attributed to some patterning defects and spurious nucleation on oxide side walls. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Future high temperature applications for SiC integrated circuits
Authors: Zetterling Carl‐Mikael , Lanni Luigia , Ghandi Reza , Malm B. Gunnar , Östling Mikael
Published: May 2012

The main advantage of SiC is its high critical field for breakdown. This leads to much lower on‐resistance for high voltage devices compared to silicon, but at a higher price that has to be offset by system gains. However, it is not straightforward to exploit this advantage, which is clear from the many different device types that are presently being commercialized. There are other advantages of SiC yet to be fully investigated: the possibility of high temperature operating electronics and radiation hard devices. If integrated circuits in SiC are also available, the system advantage is larger. Here temperature ranges higher than that of SOI should be aimed at, and some of these new application areas will be described. An overview of IC research will be ended with a description of our selected technology operated at 300 °C (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Discrimination of surface‐scattering mechanisms in waveguides with a rough boundary of rectangular power spectrum
Authors: Rendón M. , Makarov N. M.
Published: May 2012

We study transport properties of a single‐mode waveguide with rough boundary. As is known, propagating waves in such waveguides are attenuated because of two mechanisms of surface scattering: the amplitude mecha‐ nism and the square‐gradient mechanism. While the former is known since long ago, the latter was recently predicted. In general, they compete with one another and, then, it is difficult to study them individually.

Here, by means of appropriate long‐range correlations specified by two correlation parameters and embedded in the disordered boundary of the waveguide, we man‐ age to separate these mechanisms and stop the competition. Specifically, we arrange different intervals of wave numbers in which they manifest themselves alone. This situation allows one to study the different nature of these scattering mechanisms. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dielectric properties of PMN+2%Li2O at low frequencies
Authors: Bormanis K. , Kalvane A. , Burkhanov A. I. , Tumanov I. E. , Mironova‐Ulmane N.
Published: May 2012

The reported study is focused on effects of the admixture of lithium (2% Li2O) on the low‐frequency dielectric response in lead magnesium niobate ceramics over the 100 ‐300 K range of temperature. The obtained results reveal an essential thermal broadening of the ε′(ν) spectra specific to relaxor ferroelectrics. Dispersion Δε′ = ε′1Hz‐ε′1kHz and values of ε′′(ν) in lead magnesium niobate ceramics containing Li are well described by the Cole‐Cole equation at temperatures below the ε′(T) maximum. Based on the analysis of the experimental data admixture of lithium is suggested to promote formation of domains in lead magnesium niobate ceramics (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Blanket and patterned growth of CdTe on (211)Si substrates by metal‐organic vapor phase epitaxy
Authors: Bhat Ishwara B. , Rao Sunil R. , Shintri Shashidhar , Jacobs Randolph N.
Published: May 2012

Metalorganic vapor phase epitaxy (MOVPE) of (211)B CdTe on (211)Si using intermediate Ge and ZnTe layers has been achieved for use as substrates for the growth of HgCdTe infrared detector materials. The best (211)B CdTe films grown in this study display a low X‐ray diffraction (XRD) rocking‐curve full‐width‐at‐half‐maximum (FWHM) of 64 arcs for a 12 µm thick layer and Everson etch pit density (EPD) of 3x105cm‐2. In order to reduce the threading dislocation density further, growth on patterned layer has been investigated using Si3N4 as the mask. In order to achieve selective nucleation on patterned layer, process parameters were first developed. A circular pattern was used to study the anisotropy during growth and to identify the optimum orientation for parallel stripe growth windows. The optimum growth window was then used for the growth of completely merged layers (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Studies of surface oxidation in ultrasmall magic‐sized white‐light emitting CdSe nanocrystals using X‐ray photoelectron spectroscopy
Authors: Sohel Mohammad A. , Pan Liang , Tamargo Maria C.
Published: May 2012

A large number of II‐VI and III‐V semiconductor nanocrystals (NCs) or quantum dots (QDs) have been studied over the years because of their size and band gap tunable optical properties, and their application in miniaturizing optoelectronic devices. Significant studies have been done in the synthesis and characterization of CdSe NCs, and their surface has been studied using X‐ray photoelectron spectroscopy (XPS). Recently, pyrolytically grown white‐light (WL) emitting ultra small, “magic size” CdSe NCs with an absorption feature at 414 nm and a broadband emission between 420 and 710 nm have been reported which show no band edge emission. Due to the extreme surface‐to‐volume ratio, the electrons and holes apparently interact on the surface producing a broad emission covering the entire visible spectrum. Due to the technological interest as white‐light phosphors for application in white light emitting diodes (LEDs), it is important to understand the surface coverage of the ligands on the surface of the CdSe NCs, and oxidation of these NCs. This paper reports the surface oxidation of these ultra‐small white‐light emitting CdSe NCs and effect of their relevant ratios of Cd and Se surface atoms as compared to regular CdSe NCs using X‐Ray Photoelectron Spectroscopy. Results shows that the degree of oxidation in the ultra small white light emitting NCs is quiet comparable to that of larger size NCs and makes it more suitable for application in optoelectronics and miniature of devices in white light emitting devices. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)