bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic Memory Effect of Nanocomposites
Authors: Razzaq M. Y. , Behl M. , Lendlein A.
Published: October 2011

The magnetic memory effect (MME) is the ability of magneto‐sensitive materials to remember the magnetic field strength (Hdef), at which they were deformed recently. They respond close to Hdef either by recovering their initial shape at a switching magnetic field strength Hsw under stress‐free conditions or by building up stress with a peak maximum at Hσ,max under constant strain conditions. This paper explores whether such a MME can be created for polymer‐based nanocomposites. The concept is based on temperature‐memory polymers (TMP) as matrix, in which silica coated iron(III)oxide nanoparticles (mNP) are dispersed. The MME was explored in a cyclic magneto‐mechanical test, in which the nanocomposite sample was elongated to ϵm while being exposed to an alternating magnetic field at Hdef. The magnetic memory was read out by determining Hσ,max or Hsw. A linear correlation between Hσ,max (or Hsw) and Hdef in a range from 15 to 23 kA m−1 at a fixed frequency of f = 258 kHz is observed and demonstrates the excellent magnetic memory properties of the investigated nanocomposites containing either crystallizable or amorphous, vitrifiable domains as controlling units. The deformation ϵm at Hdef can be fixed with an accuracy of more than 72% and the initial shape can be recovered almost completely by more than 86%. The MME allows the design of magnetically programmable devices such as switches or mechanical manipulators.
Polydiphenylamine–polyethylene oxide blends as methanol sensing materials
Authors: Permpool Tharaporn , Supaphol Pitt , Sirivat Anuvat , Wannatong Ladawan , Sirivat Anuvat
Published: October 2011

This work aims to investigate the electrical conductivity sensitivity of polydiphenylamine (PDPA) pellets, films, and fibers when they are exposed to methanol vapor. PDPA was synthesized via chemical oxidative polymerization and washed with NH4OH solution to obtain the de‐doped‐PDPA (De‐PDPA). De‐PDPA pellets were doped with hydrochloric acid at various doping ratios. PDPA and its blends with polyethylene oxide (PEO) added at various ratios were successfully fabricated into fibers by electrospinning and cast into films. The De‐PDPA pellet doped at the doping ratio of 100 has the highest electrical conducitivity sensitivity toward methanol vapor. The electrical conductivity sensitivity of the PDPA electrospun fiber is relatively lower than those of the D‐PDPA cast films under methanol vapor. The methanol vapor induces a higher degree of crystallinity in the conductive polymer matrix and resultant higher electron mobility. The adsorption of methanol vapors is investigated via FTIR and the interaction is irreversible. © 2011 Wiley Periodicals, Inc. Adv Polym Techn 31: 401–413, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.20263
Perioperative care in functional endoscopic sinus surgery: a survey study
Authors: Portela Rafael Antonio , Hootnick Jessica , McGinn Johnathan
Published: October 2011

Background:

Functional endoscopic sinus surgery (FESS) is largely viewed as the standard of care in the treatment of chronic rhinosinusitis (CRS) refractory to medical treatment. While there is an understanding regarding the importance of some form of routine postoperative FESS care, no consensus currently exists regarding what the specific management routine should include. The authors of this survey study did not intend to examine the efficacy of such treatment protocols, but rather to determine and report on the current practice patterns of perioperative FESS care among otolaryngologists.

Methods:

This survey study was designed in accordance with and approved by our institutional review board. The online‐based survey was designed using the online product SurveyMonkey®. A total of 859 otolaryngologists were identified and email addresses were obtained from the American Academy of Otolaryngology‐Head and Neck Surgery (AAO‐HNS) website directory. Responses were collected anonymously.

Results:

Our survey response rate was 32%. Multiple parameters of the otolaryngologists' perioperative care were collected. Among the data, some consistent patterns emerged: 93.2% of respondents use nasal saline irrigations postoperatively; 86.8% of otolaryngologists surveyed prescribe antibiotics in the immediate postoperative period; and office‐based endoscopic sinus debridements are performed by a majority (87.9%) of those surveyed.

Conclusion:

This survey study demonstrates that current practices in perioperative FESS care can vary widely among otolaryngologists, and are not uniformly based on evidence‐based outcomes research. Despite the lack of absolutes regarding the specific perioperative care in FESS, practice patterns emerge from the data regarding typical perioperative management among current otolaryngologists. © 2011 ARS‐AAOA, LLC.
Artificial ageing of wood finishes monitored by IR analysis and color measurements
Authors: Irmouli Youcef , George Béatrice , Merlin André
Published: October 2011

Photocurable finishes appear now as very attractive products for industrial wood joinery for reducing volatile organic compounds (VOC). Nevertheless their poor durability is currently reported. In this study, we aimed to enhance stability of advanced formulations based on photoinitiators working under UV‐visible light by introducing UV absorbers, the absorption band of which is shifted compared to the band of initiators. We tested the efficiency of these stabilizers for two curable coatings applied onto oak and spruce. Modifications of samples at molecular and macroscopic scales were quantified after an accelerated ageing process by FTIR spectroscopy, measurements of color variations, apparition of cracks. It appears that both UV absorbers tested do not greatly improve the durability of systems and the results obtained allow to better understand the causes of the poor characteristics of the finishing systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis, characterization, and thermal analysis of two polymeric chromium ternary complexes with nitrilotriacetic acid and alanine or glycine
Authors: Ismail Eman H. , Souaya Eglal R. , Mohamed Amr A.
Published: October 2011

Two chromium ternary complexes with nitrilotriacetic acid as a primary ligand and alanine or glycine as secondary ligand were prepared in slightly acidic medium. The structure of these two complexes was characterized using elemental, thermal analysis, FTIR spectra, and the two complexes mass spectra. The spectroscopy data suggest that these two complexes were in polymeric form and have the monomeric unit H[Cr(HNTA)(Hala)(SO4)] and H[Cr(HNTA)(Gly)(SO4)] in which sulfate group act as a bidentate ligand linked between each monomeric unit for the same complex. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Intumescent flame retardant TPO composites: Flame retardant properties and morphology of the charred layer
Authors: Wang Xu , Feng Na , Chang Suqin , Zhang Guixia , Li Hong , Lv Hongfei
Published: October 2011

Intumescent flame retardant thermoplastic polyolefin (TPO) composites were prepared to study the relationships between their structure of charred layer (including of the multicellular intumescent layer and the charry layer) and flame retardant properties. They were characterized using the LOI and UL‐94 test, which indicated that the best fire retardant behavior (V‐0 rating and LOI reach to 28.1%) was obtained at the formulation of TPO/ammonium dihydrogen phosphate/starch (100/60/20). Thermal gravimetric analysis demonstrated that the presence of ammonium dihydrogen phosphate/starch promoted the esterification and carbonization process in lower temperature range while enhancing the thermal stability of intumescent flame retardant TPO in high‐temperature range. Scanning electron microscope and optical microscope were shown that, with combustion time prolonged, the intumescent layers obtained greater number of cells, and the charry layer became more compact while the size of the carbon granules became smaller on the surface. Introduction of starch had an obvious effect on the structure of the intumescent and charry layers. The charry layer of the composites with the content of 20 phr starch was more compact and uniform than that of the composites with 50 phr. The weight ratio of ammonium dihydrogen phosphate to starch in the intumescent flame retardant was fixed as 3 : 1 which cooperated with each other well to promote a compact charry layer and to obtain the better flame retardancy performance. Therefore, the better the charred layers produced, and the better flame retardant properties they obtained. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of colloidal β‐cyclodextrins–Fe3O4 magnetic nanoparticles on the chemiluminescence enhancement of luminol–Ag(III) complex for rapid and sensitive determination of cysteine in human serum
Authors: Rezaei B. , Ensafi A. A. , Zarei L. , Kameli P.
Published: October 2011

Colloidals solution of Fe3O4 magnetic nanoparticles (MNPs), capped with β‐cyclodextrins (β‐CD) as inclusion complexes, were found to enhance the chemiluminescence (CL) intensity of the luminol–diperiodatoargentate(III) (DPA) system. On injection of cysteine into the luminol–DPA–β‐CD–Fe3O4 MNPs inclusion complexes system, the CL intensity is strongly enhanced. The enhanced CL signal is ascribed to the catalytic effect of Fe3O4 MNPs capped with β‐CD, which is assumed to stabilize the CL intermediate. Based on these findings, a rapid and sensitive assay was developed for the determination of cysteine in human serum. The effects of analytical variables on the CL signal were studied and optimized. Under the optimum conditions, the CL intensity was directly proportional to the concentration of cysteine in the range 8.0 × 10–9–1.0 × 10–6 mol/L. The detection limit was 2.8 × 10–9 mol/L (3 Sb/m) and the relative standard deviation (RSD) for 10 replicate determinations of 1.0 × 10–7 mol/L cysteine was 3.5%. The proposed method was applied to the sensitive determination of cysteine in human serum samples, and compared with the Ellman method with satisfactory results. Copyright © 2011 John Wiley & Sons, Ltd.
Steam reforming of ethanol on a Ni/Al2O3 catalyst coupled with a hydrotalcite‐like sorbent in a multilayer pattern for co2 uptake
Authors: Cunha A. F. , Wu Y. J. , Díaz Alvarado F. A. , Santos J. C. , Vaidya P. D. , Rodrigues A. E.
Published: October 2011

Steam reforming of ethanol (SRE) on a Ni/Al2O3 catalyst was studied. The effects of the operating conditions and catalyst nature on the course of reaction were evaluated. Hydrogen was generated in the temperature range between 100 and 600°C. A mechanism was used to explain the reaction pathways. A commercial hydrotalcite‐like sorbent arranged in a multilayer pattern of catalyst and sorbent was used for CO2‐uptake to enhance hydrogen production. The concept of sorption enhanced reaction process on SRE is illustrated by the operation of catalyst and CO2‐sorbent at 400°C. A lower flow rate regime and multilayer pattern system enhances hydrogen production in the initial breakthrough periods. CO appears in traces in the product gas stream. © 2011 Canadian Society for Chemical Engineering
Extraction and Determination of Quercetin and Myricetin from Chamaecyparis obtusa by Ionic Liquids‐based Monolithic Cartridge
Authors: Zhu Tao , Bi Wentao , Row Kyungho
Published: October 2011

A short ionic liquids (ILs)‐based monolithic cartridge was prepared and used as the selective extraction sorbent. After the material was evaluated by field emission‐scanning electron microscopy (FE‐SEM), a new approach for the extraction and determination of quercetin and myricetin from Chamaecyparis obtusa (C. obtusa) by using ILs‐based, monolithic cartridge system was developed. Chromatographic analysis was conducted on a C18 column with UV detection at 372 nm, an eluting solution consisting of acetonitrile‐water (25/75,V/V) as the mobile phase, and a flow rate of 0.7 mL·min−1. A good linear relationship was demonstrated when the concentrations of quercetin and myricetin were in the range of 0.5–100.0 µg·mL−1. The recoveries ranged from 101.6% to 104.6% and the inter‐ and intra‐day relative standard deviations (RSD) were less than 5.0%. This method effectively removed the impurities and avoided tedious pretreatment. It provided a fast, economic and effective method for assaying trace drugs from natural plants.
Robust CoAl Alloy: Highly Active, Reusable and Green Catalyst in the Hydrogenolysis of Glycerol
Authors: Guo Xiaoyang , Yin Anyuan , Guo Xiaodong , Guo Xiuying , Dai Weilin , Fan Kangnian
Published: October 2011

CoAl alloy catalyst is found, for the first time, to be highly active, selective and reusable for the synthesis of diols via the hydrogenolysis of glycerol under mild conditions. The products and the catalyst could be self‐separated from the reaction system through a simple reactor.
Eco‐friendly and Efficient Synthesis of 2,3‐Dihydroquinazolin‐4(1H)‐ones
Authors: Majid Ghashang , Kobra Azizi , Hamed Moulavi‐Pordanjani , Hamid Reza Shaterian
Published: October 2011

A simple and facile method for the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐ones through the direct cyclocondensation of one‐pot three‐component cyclocondensation of isatoic anhydride, ammonium acetate (or primary amines) and aldehydes; and anthranilamide and aldehydes using silica supported ferric chloride (SiO2‐FeCl3) as catalyst under solvent‐free conditions is described.
(+)‐Tartaric Acid‐Catalyzed High Regio‐ and Stereoselective Aminobromination of Olefins
Authors: Chen Zhanguo , Wei Junfa , Li Wenli , Wang Yun , Zhao Pengfei , Shi Xianying
Published: October 2011

(+)‐Tartaric acid‐catalyzed aminobromination of α,β‐unsaturated ketones, α,β‐unsaturated esters and simple olefins utilizing TsNH2/NBS as the nitrogen/halogen sources at room temperature without protection of inert gases achieved good yields (up to 92% yield) of vicinal haloamino products with excellent regio‐ and stereoselectivity, even just 10% of (+)‐tartaric acid was used as catalyst. The regio‐ and stereochemistry was unambiguously confirmed by X‐ray structural analysis of products 2b and 12c. The electron‐rich and deficient olefins show significant differences in activity to the aminobromination reaction and give the opposite regioselectivities. The 21 cases have been investigated which indicated that our protocol has the advantage of a large scope of olefins. Additionally, tartaric acid as catalyst has the advantage of avoiding any hazardous metals retained in products.
Effect of Poly(ethylene glycol)‐400 and Carbon on MoO3 Nanocomposite Materials and Its Catalytic Activity
Authors: Navgire Madhukar , Yelwande Ajeet , Arbad Balasaheb , Lande Machhindra
Published: October 2011

The effect of addition of poly(ethylene glycol)‐400 (PEG‐400) and carbon (0, 1, 2 and 3 wt%) as substrates were investigated systematically to get the desired phase of carbon‐doped MoO3 material. The carbon source was prepared from the Acacia arabica plant wood. The resulting samples were calcined at 500°C. The effect of PEG‐400 and carbon composite on the structure, particle size and morphology were investigated. The prepared samples were characterized by XRD, SEM‐EDS and FT‐IR techniques. The samples with PEG‐400 and carbon addition give better control of particle size and porosity. The prepared catalysts were tested for the synthesis of 3,4‐dihydropyrimidones via the Biginelli‐type condensation reaction. This new method consistently has the advantage of excellent yields (88%–93%) and short reaction times (1.5–3 h) than do classical Biginelli reaction conditions.
Mn(III)‐Mediated Chlorination of Conjugated Ketones
Authors: Liu Xingchao , Wang Lu , Zou Jianping
Published: October 2011

Mn(III)‐Cl formed by the reaction of Mn(OAc)3 and hydrochloric acid in situ, reacted with α,β‐unsaturated ketones readily to afford α,β‐dichloroketones in good yields under mild conditions. The products are key precursors for synthesis of conjugated alkynones and other organic compounds.
Microwave‐Assisted Aqueous Synthesis: A Rapid Approach to Poly‐functionalized Indoline‐Spiro Benzofurodiazepines
Authors: Wang Shuliang , Cheng Chuang , Gong Feng , Wu Feiyue , Jiang Bo , Zhou Jianfeng , Tu Shujiang
Published: October 2011

New cycloaddition has been established for the synthesis of indoline‐spiro benzofurodiazepine derivatives. Those reactions were conducted by reacting readily available and inexpensive starting materials, such as benzene‐1,2‐diamines, tetronic acid and indoline‐2,3‐diones, in aqueous solution under microwave irradiation. When mono‐substituted benzene‐1,2‐diamines as an amine component was employed, the reaction regioselectively resulted in the poly‐functionalized indoline‐spiro benzofurodiazepine with good yields. The present green synthesis shows attractive characteristics such as the use of water as reaction media, concise one‐pot conditions, short reaction periods, easy work‐up/purification and reduced waste production without the use of any strong acids or metal promoters.
Convenient Synthesis of 3,5‐Biscarbamoyl‐pyridine Derivatives
Authors: Wang Xiayun , Zhu Yiwen , Zhang Min , Lu Dongliang , Qian Qun , Chen Yali , Cao Weiguo , Song Liping , Deng Hongmei
Published: October 2011

An efficient and convenient method for synthesis of 3,5‐bis‐carbamoyl‐2,6‐dimethylpyridine derivatives was achieved in good to excellent yields by reaction of anilines with 3,5‐bis(3′,5′‐dimethyl‐1′‐pyrazolyl‐carbonyl)‐2,6‐dimethylpyridine, in which pyrazoles served as leaving groups. The structures of products were confirmed by spectra data and microanalysis.
Determination of Parathion‐methyl in Vegetables by Fluorescent‐Labeled Molecular Imprinted Polymer
Authors: Sun Qian , Yao Qianqian , Sun Zhoulin , Zhou Tianshu , Nie Dongxia , Shi Guoyue , Jin Litong
Published: October 2011

A novel sensor for the determination of parathion‐methyl based on couple grafting of functional molecular imprinted polymers (MIPs) was fabricated which is developed by anchoring the MIP layer on surfaces of silica particles embedded CdSe quantum dots by surface imprinting technology. The synthesized molecular imprinted silica nanospheres (CdSe@SiO2@MIP) allow a high selectivity and sensitivity of parathion‐methyl via fluorescence intensity decreasing when the MIP material rebinding the parathion‐methyl molecule. Compared with the MIP fabricated in traditional method, the template of parathion‐methyl was easier to remove from the CdSe@SiO2@MIP imprinted material. Under optimal conditions, the fluorescence intensity of parathion‐methyl at the imprinted sensor was detected by spectrofluorophotometer. The relative fluorescence intensity of CdSe@SiO2@MIP decreased linearly with the increasing concentration of parathion‐methyl ranging from 0.013 mg·kg−1 to 2.63 mg·kg−1 with a detection limit (3δ) of 0.004 mg·kg−1 (S/N=3), which is lower than the MIP in tradition. The imprinted film sensor was applied to detect parathion‐methyl in vegetable samples without the interference of other organophosphate pesticides and showed a prosperous application in the field of food safety.
Preconcentration/Separation of Some Metal Ions Using Sodium Dodecyl Sulfate Coated Alumina Modified with Bis(5‐bromo‐2‐hydroxy‐benzaldehyde)‐2‐methyl‐1,5‐pentane Diimine (BBHBPDI) Prior to Their Flame‐AAS Determination
Authors: Ghaedi Mehrorang , Montazerozohori Morteza , Marahel Farzaneh , Nejati Biareh Mehdi , Soylak Mostafa
Published: October 2011

Preconcentration/separation of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions using bis(5‐bromo‐2‐hydroxy‐benzaldehyde)‐2‐methyl‐1,5‐pentane diimine (BBHBPDI) on SDS coated alumina has been reported. The influences of the analytical parameters including pH, ligand and SDS amount, type and concentration of eluent and sample volume on metal ions recoveries were investigated. At optimum values of all variables the relative standard deviation are between 2.5–2.7 and preconcentration factor was 375, while recoveries for all understudy metal ions are higher than 95%, determination limits are between 1.5–2.7. The method has been successfully applied to determination of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions content in some real samples.
A Sensitive Simultaneous Determination of Adrenalin and Paracetamol on a Glassy Carbon Electrode Coated with a Film of Chitosan/Room Temperature Ionic Liquid/Single‐Walled Carbon Nanotubes Nanocomposite
Authors: Babaei Ali , Babazadeh Mitra , Afrasiabi Mohammad
Published: October 2011

The present work demonstrates that simultaneous determination of adrenalin (AD) and paracetamol (PAR) can be performed on single‐walled carbon nanotube/chitosan/ionic liquid modified glassy carbon electrode (SWCNT‐CHIT‐IL/GCE). The electro‐oxidations of AD and PAR were investigated with cyclic voltammetry (CV), differential pulse voltammetry (DPV) and also chronoamperometry (CA) methods. DPV experiments showed that the oxidation peak currents of AD and PAR are proportional to the corresponding concentrations over the 1–580 μmol/L and 0.5–400 μmol/L ranges, respectively. The RSD at a concentration level of 15 μmol/L AD and 15 μmol/L PAR were 1.69% and 1.82%, respectively. Finally the modified electrode was used for simultaneous determination of AD and PAR in real samples with satisfactory results.
Influence from Thermal Elimination Temperature of Precursor Polymer and Film‐forming Methods on the Photophysics of the Poly(2,5‐didodecyloxy‐p‐phenylenevinylene)
Authors: Wang Shangli , Zhao Wei , Xu Xiaoqian , Cheng Si , Fan Lijuan
Published: October 2011

A series of poly(p‐phenylenevinylene)s (PPVs) with good solubility were synthesized from thermal elimination of precursor poly(2,5‐didodecyloxy‐p‐phenylenevinylene) at different temperature via Wessling method. The polymer photophysics were influenced by the thermal elimination condition, which was consistent with NMR and IR characterizations. The additional absorption peak at longer wavelength and the red‐shifted emission maximum both in solution and in film, for PPVs obtained at high elimination temperature, indicated the existence of longer conjugated blocks in these systems. The emission maximum for drop‐cast film (436 nm) for PPV obtained under 200°C (PPV200) was 16 nm blue shifted to the spin‐coated films (452 nm) or 29 nm to the solution (465 nm). The SEM study showed drop‐cast film had the morphology of isolated conjugated particles in the matrix while blurry linear structure was found for spin‐coated film, which was consistent with the photophysics. The discussion about this difference was carried out based on the consideration of the flexibility of the polymer chains and different conjugated length of PPV in different states.
Prognostic value of positive human epidermal growth factor receptor 2 status and negative hormone status in patients with T1a/T1b, lymph node‐negative breast cancer
Authors: Livi Lorenzo , Meattini Icro , Saieva Calogero , Franzese Ciro , Di Cataldo Vanessa , Greto Daniela , Franceschini Davide , Scotti Vieri , Bonomo Pierluigi , Nori Jacopo , Sanchez Luis , Vezzosi Vania , Bianchi Simonetta , Cataliotti Luigi , Biti Giampaolo
Published: October 2011

BACKGROUND:

The objective of this study was to evaluate prognostic factors of local and distant recurrence in patients diagnosed with T1a and T1b, lymph node‐negative breast carcinoma (BC) with emphasis on human epidermal growth factor receptor 2 (HER2) status.

METHODS:

The authors reviewed 704 women with T1aT1bN0M0 BC who received treatment at the Radiation‐Oncology Center of Florence University between November 2002 and December 2008. Patients with ductal carcinoma in situ or recurrent BC at presentation and patients who received adjuvant chemotherapy were excluded from the analysis.

RESULTS:

In total, 75 patients had HER2‐positive BC (10.7%). At a mean follow‐up of 4.9 years (standard deviation, 2.6 years; range, 0.5‐10.8 years), 19 events were identified, including 10 distant recurrences. Patients with HER2‐positive BC had worse distant recurrence‐free survival (DRFS) than patients with HER2‐negative BC (hazard ratio, 3.66; 95% confidence interval, 0.94‐14.69; P = .045). Negative hormone receptor (HR) status was associated significantly with worse DRFS (hazard ratio, 0.26; 95% confidence interval, 0.07‐0.93; P = .026). In multivariate analysis, younger age was the only significant risk factor for an event of recurrence (hazard ratio, 0.61;95% confidence interval, 0.20‐1.82; P = .029).

CONCLUSIONS:

The current results indicated that patients with T1a/T1b, lymph node‐negative BC have a low risk of distant and local recurrence, but younger age is a significant risk factor for events occurrence. Young women with HER2‐positive and HR‐negative status have a significant risk of distant recurrence and should be considered for future clinical trials with anti‐HER2 adjuvant therapy. Cancer 2011. © 2011 American Cancer Society.
Single‐stage single‐switch PFC converter for wide‐input extreme step‐down voltage applications
Authors: Ismail Esam H. , Al‐Saffar Mustafa A. , Sabzali Ahmad J. , Zerai Adel A.
Published: October 2011

This paper presents a new single‐stage single‐switch high power factor correction AC/DC converter suitable for low‐power applications (< 150 W) with a universal input voltage range (90–265 Vrms). The proposed topology integrates a buck–boost input current shaper followed by a buck and a buck–boost converter, respectively. As a result, the proposed converter can operate with larger duty cycles compared with the existing single‐stage single‐switch topologies, hence, making them suitable for extreme step‐down voltage conversion applications. Several desirable features are gained when the three integrated converter cells operate in discontinuous conduction mode. These features include low semiconductor voltage stress, zero‐current switch at turn‐on, and simple control with a fast well‐regulated output voltage. A detailed circuit analysis is performed to derive the design equations. The theoretical analysis and effectiveness of the proposed approach are confirmed by experimental results obtained from a 100‐W/24‐Vdc laboratory prototype. Copyright © 2011 John Wiley & Sons, Ltd.
The (β‐Diketiminato)bismuth(III) Complex [LBiCl(μ‐Cl)]2 {L = HC[(CMe)(NAr)]2, Ar = 2,6‐iPr2C6H3} and Its Derivatives: The Presence of Versatile Ligand Ligation Modes
Authors: Li Yan , Zhu Hongping , Tan Gengwen , Zhu Tao , Zhang Jinyuan
Published: October 2011

The reaction of BiCl3 with LLi {L = HC[(CMe)(NAr)]2, Ar = 2,6‐iPr2C6H3} in a molar ratio of 1:1 was carried out under various conditions and afforded [LBiCl(μ‐Cl)]2 (1), [L′BiCl(μ‐Cl)]2 [4; L′ = N(Ar)=C(Me)CH=C(NHAr)CH2], and L″Bi2Cl4 [5; L″ = N(Ar)=C(Me)CC(Me)=N(Ar)]. Compounds 1 and 4 are isomers, and a thermal conversion of 1 to 4 was realized. In this reaction system, when a little excess nBuLi and BiCl3 were used, [LBiCl(μ‐Cl)Bi(nBu)Cl(μ‐Cl)]2 (2) was isolated as side product after the isolation of 1. The reaction of 1 with AgOOCCF3 in the absence of light from –15 °C to room temperature generated LBi(OOCCF3)2 (3). Finally, the solvent‐free reaction of BiCl3 and LH at elevated temperature (125 °C) under vacuum gave [LH2]+[BiCl4(THF)]– (6) in a low yield. The formulations of all these complexes have been confirmed by 1H and 13C NMR spectroscopy and X‐ray crystallography, except for 6, which was only identified by X‐ray crystallography due to its insolubility in organic solvents. These complexes exhibit versatile L ligation modes at the metal atom and reveal the complexity of the reaction between BiCl3 and LLi.
Motion, deformation and aggregation of two cells in a microchannel by dielectrophoresis
Authors: Ye Ting , Li Hua , Lam Khin Yong
Published: October 2011

The dynamic behavior of two cells in a microchannel subject to a nonuniform electric field is simulated numerically by a two‐fluid model in the present work. Owing to the presence of nonuniform electric field, usually the cells are polarized and then the dielectrophoresis occurs. The dielectrophoretic force induces the movement and deformation of cells in the microchannel. Meanwhile, the cell membrane develops a mechanical force to resist the cell deformation. In addition, the intercellular interaction becomes dominant when the cell–cell distance is short enough such that an intercellular force is generated. The three forces are taken into account in the two‐fluid model to characterize the dynamic behavior of cells. In order to validate the present model, the cell deformation is calculated and compared with the experimental results published previously, where a quantitative agreement is achieved. It is demonstrated by simulations that the cell conductivity mainly determines the motion and deformation of cells at low frequency. Instead of the cell conductivity however, the cell permittivity plays a critical and leading role at high frequency. These phenomena are consistent with the experimental observations. Furthermore, the intercellular interaction may cause the change in the dynamic behavior of cells.
Tumor microenvironment composition in pediatric classical Hodgkin lymphoma is modulated by age and Epstein‐Barr virus infection
Authors: Barros Mário Henrique M. , Vera‐Lozada Gabriela , Soares Fernando A. , Niedobitek Gerald , Hassan Rocio
Published: October 2011

Classical Hodgkin lymphoma (cHL) is characterized by a small number of neoplastic cells in a background of reactive cells. Children and adults differ in constitution and functionality of the immune system and it is possible that there may be age‐related differences in tumor microenvironment composition in cHL. One hundred children with pediatric cHL were studied. Tumor‐infiltrating lymphocytes were analyzed by immunohistochemistry (IHC) and image analysis. Epstein‐Barr virus (EBV) status was determined by EBER‐specific in situ hybridization and IHC. Results were analyzed in the context of age‐group, histological characteristics and clinical follow‐up. EBV‐status was not associated with age‐group. Children <10 years and EBV+ cases were characterized by a more intense T cell infiltrate, exhibiting a cytotoxic/Th1 profile, characterized by higher numbers of CD3+, CD8+, TIA1+ and TBET+ lymphocytes. Extranodal disease (p = 0.016) and high number of GranzymeB+ lymphocytes (p = 0.04) were independently associated with reduced progression‐free survival (PFS). Yet, in EBV+ cases, improved outcome was observed in cases with low numbers of FOXP3+ lymphocytes (p = 0.046), FOXP3/CD8 ratio < 1 (p = 0.021) and TBET/CMAF ratio < 1 (p = 0.017). By contrast, in EBV− cases, poor survival was observed in cases with extranodal disease (p = 0.028), MC subtype (p = 0.009) and high numbers of TIA1+ (p = 0.044) and GranzymeB+ (p = 0.04) lymphocytes. The results suggest that in EBV+ cHL an effective immune response directed against viral or tumor antigens may be triggered in the tumor microenvironment and that physiological and age‐related changes of the immune system may also modulate the tumor microenvironment in pediatric cHL.
Practices of Productive Adult Book Clubs
Authors: Beach Richard , Yussen Steven
Published: October 2011

This article examines two adult book club members’ responses to literary texts over a 23‐month period to identify practices that contribute to productive book club participation. Members were interviewed regarding their book selection procedures, preparation for and perceptions of the discussions, and what they valued about the discussions. Discussions were analyzed in terms of book club members drawing on their knowledge and expertise to interpret texts, developing topics based on the number of different turns per topic, and adopting “point‐driven” versus “story‐driven” stances. Three basic factors are identified as contributors to productive book club participation: (1) the use of codified, vetted selection procedures; (2) collaborative sharing of knowledge and expertise to provide insights into books in ways that transcend members’ individual responses; and (3) the development of discussion topics through building on members’ interpretations.
Classroom Remix: Patterns of Pedagogy in a Techno‐Literacies Poetry Unit
Authors: Callahan Meg , King Jennifer M.
Published: October 2011

Researchers collaborated with two high school creative writing teachers to consider how a particular use of technology—PowerPoint poetry interpretations—would function in their creative writing classes. Their findings encouraged them to consider three kinds of “classroom remix” related to the introduction of techno‐literacy practices into the curricular activities: (1) “composition remix,” which refers to the blending of visual, linguistic, and auditory composition elements afforded by PowerPoint technology; (2) “mindset remix,” which refers to the way teachers and students create a collage of insider and outsider mindsets; and (3) “participation remix,” which refers to the distribution of knowledge, expertise, and agency. In all cases, the classroom remix created a new blend of patterns and hierarchies that led the teachers, students, and researchers to challenge assumptions and raise new questions about how language arts classrooms function in the digital age.
Aneugenic potential of the anticancer drugs melphalan and chlorambucil. The involvement of apoptosis and chromosome segregation regulating proteins
Authors: Efthimiou Maria , Stephanou Georgia , Demopoulos Nikos A. , Nikolaropoulos Sotiris S.
Published: October 2011

Previous findings showed that the anticancer drugs p‐N,N‐bis(2‐chloroethyl) amino‐l‐phenylalanine (melphalan, MEL) and p‐N,N‐bis(2‐chloroethyl)aminophenylbutyric acid (chlorambucil, CAB) belonging to the nitrogen mustard group, in addition to their clastogenic activity, also exert aneugenic potential, nondisjunction and chromosome delay. Their aneugenic potential is mainly mediated through centrosome defects. To further investigate their aneugenicity we (a) studied whether apoptosis is a mechanism responsible for the elimination of damaged cells generated by MEL and CAB and (b) investigated if proteins that regulate chromosome segregation are involved in the modulation of their aneugenic potential. Apoptosis was studied by Annexin‐V/Propidium Iodide staining and fluorescence microscopy. The involvement of apoptosis on the exclusion of cells with genetic damage and centrosome disturbances was analyzed by DAPI staining and immunofluorescence of β‐ and γ‐tubulin in the presence of pan‐caspase inhibitor. The expressions of Aurora‐A, Aurora‐B, survivin and γ‐tubulin were studied by western blot. We found that (a) apoptosis is not the mechanism of choice for selectively eliminating cells with supernumerary centrosomes, and (b) the proteins Aurora‐A, Aurora‐B and survivin are involved in the modulation of MEL and CAB aneugenicity. These findings are important for the understanding of the mechanism responsible for the aneugenic activity of the anticancer drugs melphalan and chlorambucil. Copyright © 2011 John Wiley & Sons, Ltd.
A functional haplotype in EIF2AK3, an ER stress sensor, is associated with lower bone mineral density
Authors: Liu Jie , Hoppman Nicole , O'Connell Jeffrey R , Wang Hong , Streeten Elizabeth A , McLenithan John C , Mitchell Braxton D , Shuldiner Alan R
Published: October 2011

EIF2AK3 is a type I transmembrane protein that functions as an endoplasmic reticulum (ER) stress sensor to regulate global protein synthesis. Rare mutations in EIF2AK3 cause Wolcott-Rallison syndrome (OMIM 226980), an autosomal recessive disorder characterized by diabetes, epiphyseal dysplasia, osteoporosis, and growth retardation. To investigate the role of common genetic variation in EIF2AK3 as a determinant of bone mineral density (BMD) and osteoporosis, we sequenced all exons and flanking regions, then genotyped six potentially functional single nucleotide polymorphisms (SNPs) in this gene in 997 Amish subjects for association analysis, and attempted replication in 887 Mexican Americans. We found that the minor allele of a nonsynonymous SNP rs13045 had borderline associations with decreased forearm BMD in both discovery and replication cohorts (unadjusted p = 0.036 and β = − 0.007 for the Amish; unadjusted p = 0.031 and β = − 0.008 for Mexican Americans). A meta-analysis indicated this association achieved statistical significance in the combined sample (unadjusted p = 0.003; Bonferroni corrected p = 0.009). Rs13045 and three other potentially functional SNPs, a promoter SNP (rs6547787) and two nonsynonymous SNPs (rs867529 and rs1805165), formed two haplotypes: a low-BMD associated haplotype, denoted haplotype B [minor allele frequency (MAF) = 0.311] and a common haplotype A (MAF = 0.676). There were no differences in mRNA expression in lymphoblastoid cell lines between the two haplotypes. However, after treating lymphoblastoid cell lines with thapsigargin to induce ER stress, cell lines with haplotype B showed increased sensitivity to ER stress (p = 0.014) compared with cell lines with haplotype A. Taken together, our results suggest that common nonsynonymous sequence variants in EIF2AK3 have a modest effect on ER stress response and may contribute to the risk for low BMD through this mechanism. © 2012 American Society for Bone and Mineral Research
Oral supplementation with 25(OH)D3 versus vitamin D3: Effects on 25(OH)D levels, lower extremity function, blood pressure, and markers of innate immunity
Authors: Bischoff-Ferrari Heike Annette , Dawson-Hughes Bess , Stöcklin Elisabeth , Sidelnikov Eduard , Willett Walter Churchill , Edel John Orav , Stähelin Hannes Balthasar , Wolfram Swen , Jetter Alexander , Schwager Joseph , Henschkowski Jana , von Eckardstein Arnold , Egli Andreas
Published: October 2011

To test the effect of 25(OH)D3 (HyD) compared to vitamin D3 on serum 25-hydroxyvitamin D levels (25(OH)D), lower extremity function, blood pressure, and markers of innate immunity. Twenty healthy postmenopausal women with an average 25(OH)D level of 13.2 ± 3.9 ng/mL (mean ± SD) and a mean age of 61.5 ± 7.2 years were randomized to either 20 µg of HyD or 20 µg (800 IU) of vitamin D3 per day in a double-blind manner. We measured on 14 visits over 4 months, 25(OH)D serum levels, blood pressure, and seven markers of innate immunity (eotaxin, interleukin [IL]-8, IL-12, interferon gamma-induced protein 10 kDa [IP-10], monocyte chemotactic protein-1 [MCP-1], macrophage inflammatory protein beta [MIP-1β], and “Regulated upon Activation, Normal T-cell Expressed, and Secreted” [RANTES]). At baseline and at 4 months, a test battery for lower extremity function (knee extensor and flexor strength, timed up and go, repeated sit-to-stand) was assessed. All analyses were adjusted for baseline measurement, age, and body mass index. Mean 25(OH)D levels increased to 69.5 ng/mL in the HyD group. This rise was immediate and sustained. Mean 25(OH)D levels increased to 31.0 ng/mL with a slow increase in the vitamin D3 group. Women on HyD compared with vitamin D3 had a 2.8-fold increased odds of maintained or improved lower extremity function (odds ratio [OR] = 2.79; 95% confidence interval [CI], 1.18–6.58), and a 5.7-mmHg decrease in systolic blood pressure (p = 0.0002). Both types of vitamin D contributed to a decrease in five out of seven markers of innate immunity, significantly more pronounced with HyD for eotaxin, IL-12, MCP-1, and MIP-1 β. There were no cases of hypercalcemia at any time point. Twenty micrograms (20 µg) of HyD per day resulted in a safe, immediate, and sustained increase in 25(OH)D serum levels in all participants, which may explain its significant benefit on lower extremity function, systolic blood pressure, and innate immune response compared with vitamin D3. © 2012 American Society for Bone and Mineral Research
Cortical porosity is higher in boys compared with girls at the distal radius and distal tibia during pubertal growth: An HR-pQCT study
Authors: Nishiyama Kyle K , Macdonald Heather M , Moore Sarah A , Fung Tak , Boyd Steven K , McKay Heather A
Published: October 2011

The aim of this study was to determine the sex- and maturity-related differences in bone microstructure and estimated bone strength at the distal radius and distal tibia in children and adolescents. We used high-resolution pQCT to measure standard morphological parameters in addition to cortical porosity (Ct.Po) and estimated bone strength by finite element analysis. Participants ranged in age from 9 to 22 years (n = 212 girls and n = 186 boys) who were scanned annually for either one (11%) or two (89%) years at the radius and for one (15%), two (39%), or three (46%) years at the tibia. Participants were grouped by the method of Tanner into prepubertal, early pubertal, peripubertal, and postpubertal groups. At the radius, peri- and postpubertal girls had higher cortical density (Ct.BMD; 9.4% and 7.4%, respectively) and lower Ct.Po (–118% and–56%, respectively) compared with peri- and postpubertal boys (all p < 0.001). Peri- and postpubertal boys had higher trabecular bone volume ratios (p < 0.001) and larger cortical cross-sectional areas (p < 0.05, p < 0.001) when compared with girls. Based upon the load-to-strength ratio (failure load/estimated fall force), boys had lower risk of fracture than girls at every stage except during early puberty. Trends at the tibia were similar to the radius with differences between boys and girls in Ct.Po (p < 0.01) and failure load (p < 0.01) at early puberty. Across pubertal groups, within sex, the most mature girls and boys had higher Ct.BMD and lower Ct.Po than their less mature peers (prepuberty) at both the radius and tibia. Girls in early, peri-, and postpubertal groups and boys in peri- and postpubertal groups had higher estimates of bone strength compared with their same-sex prepubertal peers (p < 0.001). These results provide insight into the sex- and maturity-related differences in bone microstructure and estimated bone strength. © 2012 American Society for Bone and Mineral Research
A facile synthesis of 2‐alkyl‐3‐α‐carboxy‐α‐styryl/heterylvinyl quinazolin‐4(3H)‐ones and 3‐arylidene/heterylmethylidene‐4‐aroyl‐1H‐[1,4]benzodiazepine‐2,5(3H,4H)‐diones and their transformation into novel heterocyclyl and heterocyclo analogues
Authors: Gupta Poonam , Sharma Archana , Sharma R. L.
Published: October 2011

Condensation of 2‐methyl‐/2‐ethyl‐ and 2‐phenyl‐/p‐tolyl‐4‐arylidene‐/heterylmethylidene‐2‐oxazolin‐5‐ones (γ‐azlactones) 2 with o‐aminobenzamide 1 in acetic acid resulted in the formation of two entirely different heterocyclic systems, differently substituted quinazoline compounds, 2‐methyl‐/2‐ethyl‐3‐α‐carboxy‐α‐styryl‐/β‐heteryl‐α‐carboxyvinyl‐quinazolin‐4(3H)‐ones 3a–3e and 3′a–3′e and differently substituted 1,4‐benzodiazepine compounds, 3‐arylidene‐/heteryl methylidene‐4‐aroyl‐1H‐[1,4]benzodiazepine‐2,5(3H,4H)‐diones 7a–7e and 7′a–7′e. Compounds 3a–3e and 3′a–3′e have been converted into compounds, 4a–4e and 4′a–4′e; 5a–5e, and 5′a–5′e; and 6a–6e and 6′a–6′e through different transformations. Benzodiazepines, 7a–7e and 7′a–7′e, on condensation with o‐phenylenediamine have generated three novel heterocyclic systems 8a–8e and 8′a–8′e; 9a–9e and 9′a–9′e; and 10a–10e and 10′a–10′e. J. Heterocyclic Chem., (2012).
Interfacing Living Yeast Cells with Graphene Oxide Nanosheaths
Authors: Yang Sung Ho , Lee Taemin , Seo Eunyong , Ko Eun Hyea , Choi Insung S. , Kim Byeong‐Su
Published: October 2011

The first example of the encapsulation of living yeast cells with multilayers of GO nanosheets via LbL self‐assembly is reported. The GO nanosheets with opposite charges are alternatively coated onto the individual yeast cells while preserving the viability of the yeast cells, thus affording a means of interfacing graphene with living yeast cells. This approach is expanded by integrating other organic polymers or inorganic nanoparticles to the cells by hybridizing the entries with GO nanosheets through LbL self‐assembly. It is demonstrated that incorporated iron oxide nanoparticles can deliver magnetic properties to the biological systems, allowing the integration of new physical and chemical functions for living cells with a combination of GO nanosheets.

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Measuring in vivo tumor pHe with CEST‐FISP MRI
Authors: Sheth Vipul R. , Li Yuguo , Chen Liu Qi , Howison Christine M. , Flask Chris A. , Pagel Mark D.
Published: October 2011

Paramagnetic chemical exchange saturation transfer (PARACEST) MRI contrast agents have been developed that can measure pH in solution studies, but these agents have not previously been detected in vivo. To use the PARACEST agent Yb‐DO3A‐oAA to measure the extracellular pH (pHe) in tumor tissue, a chemical exchange saturation transfer fast imaging with steady state precession MRI protocol was developed, the saturation period was optimized for sensitive chemical exchange saturation transfer (CEST) detection, and median filtering was used to remove artifacts in CEST spectra. These improvements were used to correlate pH with a ratio of two CEST effects of Yb‐DO3A‐oAA at a 7 T magnetic field strength (R2 = 0.99, standard deviation of precision = 0.011 pH units). The PARACEST agent could not be detected in tumor tissue following i.v. injection due to the low sensitivity of in vivo CEST MRI. Yb‐DO3A‐oAA was detected in tumor tissue and leg muscle after directly injecting the PARACEST agent into these tissues. The measured CEST effects were used to measure a tumor pH of 6.82 ± 0.21 and a leg muscle pH of 7.26 ± 0.14, and parametric pH maps were also generated from these tissue regions. These results demonstrated that tumor pHe can be measured with a PARACEST agent and a rapid CEST‐MRI protocol. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Barriers against the Migration of Mineral Oil from Paperboard Food Packaging: Experimental Determination of Breakthrough Periods
Authors: Fiselier Katell , Grob Koni
Published: October 2011

A method is described for determining the breakthrough periods through various types of potential functional barriers. A donor pack with a sheet of paper containing the test migrant(s) was tightly fixed to one side of the barrier. It included a blank sheet of paper as a spacer to rule out wetting contact between the donor and the barrier. A polyethylene film acted as a receptor on the other side. Periodically, a piece of the receptor film was analysed for the test migrants broken through the barrier. As benchmarks, periods were extrapolated for 1% and 10% breakthrough compared with equilibration. Tests were performed at 60°C, 40°C and ambient temperature. Acceleration by increased temperature gave reasonably adequate results for polyethylene but too short breakthrough periods for polypropylene, owing to structural changes in the polymer. The donor pack also included Sudan red 2, which is of sufficient volatility to migrate through the gas phase. It enabled visual control for gaps and holes in the barrier layers or cracks, e.g. from manipulation (such as bends or scratches), by red spots in the tested material behind the barrier or in the receptor film. Breakthrough data for mineral oil of the type typically used in cold‐set offset printing inks are provided for a selection of materials. Polyethylene terephthalate and polyamide showed no breakthrough for a period corresponding to 6.9 years. Copyright © 2011 John Wiley & Sons, Ltd.