bluuebunny/crossref_metadata_2025 huggingface dataset:
Reinforcement of Si3N4 nanoparticles in polypropylene single fibers through melt extrusion process and their properties
Authors: Rangari Vijaya K. , Shaik Yousuf M. , Mohammad Ghouse M. , Jeelani Shaik
Published: March 2011

We have successfully aligned/dispersed the rod and spherical‐shaped Si3N4 nanoparticles in the polypropylene (PP) fibers through melt extrusion process to fabricate polymer nanocomposite (PNC) single fibers. The alignment/dispersion of Si3N4 nanoparticles in PP/Si3N4 PNC fibers has been carried out in a systematic manner to produce uniform single fibers. The PNC fibers were first uniformly stretched and stabilized using a two‐set Godet machine. The as‐extruded single PNC fibers were tested for their thermal and tensile properties. The test results of PNC fibers were compared to neat PP polymer single fibers fabricated using the same procedure as PNC fibers. These results show that the PNC fibers are much (307%) higher in tensile strength and modulus (>1000%) when compared with the neat PP polymer single fibers. The field emission scanning electron microscope results clearly show the alignment of rod‐Si3N4 nanoparticles in polymer matrix. The differential scanning calorimetry results show ∼ 12% increase in crystallinity for rod‐Si3N4 PNCs when compared with the neat PP single fibers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Crystallization of isotactic polypropylene in the presence of a β‐nucleating agent based on a trisamide of trimesic acid
Authors: Varga József , Stoll Klaus , Menyhárd Alfréd , Horváth Zsuzsanna
Published: March 2011

Tris‐2,3‐dimethyl‐hexylamide of trimesic acid (TATA) is an new type of β‐nucleating agent for isotactic polypropylene (iPP). The crystallization, melting characteristics, and the supermolecular structure of iPP nucleated with TATA were studied on the samples crystallized under nonisothermal and isothermal conditions. The β‐nucleating ability of TATA was rather high even at low concentration. It was established that TATA possessed dual nucleating ability generating samples with mixed (α and β) polymorphic compositions. The β‐content showed an maximum value at low concentrations (10–100 ppm) of TATA. The β‐content decreased with increasing concentration of TATA in the higher concentration range. The highest β‐content (about 80%) was achieved at the crystallization temperature Tc = 110–120°C at low concentration of TATA. The crystallization curves registered at constant cooling rate or under isothermal condition have a single peak in spite of the formation of two polymorphic modifications. The crystallization isotherms cannot be linearized according to the Avrami equation because of simultaneous crystallization of the α‐and β‐forms, having different nucleation and growth rate. It was also found that the β‐content increased with increasing conversion during isothermal crystallization because of the higher growth rate of the β‐phase. The β‐phase formed in the presence of TATA consist of lamellar crystallites. In the early stage of the crystallization, hedritic structure is formed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation and properties of water‐borne polyurethane with branched straight aliphatic chains
Authors: Liu Fang , Han Dong
Published: March 2011

Water‐borne polyurethane with branched straight aliphatic chains (CWPU) was prepared and characterized by FTIR and TEM. The relationship between structure and water‐resistance of CWPU was studied. The results showed that the particle size of CWPU emulsion increases and the round particle turns into the spindle‐shaped particle with increasing of content of branched straight aliphatic chains. However, the particle size of CWPU emulsion is not sensitive to the increases of length of branched straight aliphatic chains. The water‐resistance and hydrophobic property of CWPU film increase with the increase of content and length of branched straight aliphatic chains. It is attributed to the hydrophobic layer of aliphatic chains enriched on the surface of CWPU film. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Physical properties and cure characteristics of natural rubber/nanoclay composites with two different compatibilizers
Authors: Doğan Mehmet , Oral Demet Dengiz , Yılmaz Betül , Savu Melih , Karahan Selçuk , Bayramlı Erdal
Published: March 2011

The effects of epoxidized natural rubber (ENR) and maleic anhydride‐grafted polybutadiene (PB‐g‐MA) as compatibilizers to rubber formulations with and without organo‐modified layered silicates are investigated. The physical properties and curing characteristics of composites are studied by moving die rheometer, rubber process analyzer, tensile, tear, and hardness testing. The state of organoclay intercalation was determined by X‐ray diffraction method. The addition of compatibilizers, especially ENR 50, results in further intercalation or exfoliation of the organoclay that increased the clay dispersion in the rubber matrix. ENR 50 with organo‐modified clay improves the physical properties and changes the curing profile. The addition of PB‐g‐MA without organoclay increases the tensile strength (σmax) by increasing the stock viscosity of the rubber compound. Interestingly, simultaneous increase in hardness and σmax is achieved in the presence of both compatibilizers, a characteristic that is difficult to achieve and sometimes required in rubber processing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Rheological behaviors and molecular weight distribution characteristics of bimodal high‐density polyethylene
Authors: Shen Hong‐Wang , Luan Tao , Xie Bang‐Hu , Yang Wei , Yang Ming‐Bo
Published: March 2011

A series of bimodal high density polyethylene (PE) with different molecular weight distributions (MWDs) were prepared by melt blending, and the fitting multipeaks on Gaussian were used to analyze the MWD curves, and the ratio of the areas under unimodal curves was as a tool to characterize the MWD; the phase behaviors and rheological behaviors were studied by dynamic rheological. The results showed that homogeneous bimodal high density PEs could be successfully prepared via melt blending, and the bimodal characteristic could be adjusted as expected. For samples with the MWD peak positions unvaried, the storage modulus, complex viscosity, and zero‐shear viscosity decreased rapidly with the value of AL/U increasing. Especially in the low frequency region, the loss modulus surpassed the storage modulus (G″ > G′) when AL/U > 10.17 and the dynamic cross‐point Gx appeared and increased with increasing AL/U, with an increasing extent much larger than that due to the width of MWD. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Development of ultrafine chitosan fibers through modified wetspinning technique
Authors: Pati Falguni , Adhikari Basudam , Dhara Santanu
Published: March 2011

Chitosan has been extensively exploited in biomaterials research because of easy tailorable properties. Chitosan fibers are produced through either wetspinning or electrospinning. However, it is difficult to produce few microns fibers using either of these techniques. Present study focuses on production of ultrafine chitosan fibers through modified wetspinning technique by injecting homogenous chitosan solution through a very fine hole of silicone tube into either sodium tripolyphosphate (STPP) or sodium hydroxide (NaOH) bath by applying positive pressure. The gelation behavior of the chitosan was evaluated with STPP and NaOH solution through rheological study for comparative spinnability of chitosan in STPP and NaOH bath. Although gel strength of chitosan–NaOH system (240 Pa) was four times higher than that of chitosan–STPP system, gel breakdown rate was higher in previous case. From Fourier infrared spectroscopy (FTIR) analysis, ionic cross‐linking between TPP and chitosan molecules in chitosan–TPP fibers was confirmed. Scanning electron micrographs showed fine chitosan fibers with average diameter of ∼ 10 μm. These nonwoven fibers/scaffolds with interconnected porosity may find potential biomedical applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Thermal properties and morphology of isotactic polypropylene/acrylonitrile–butadiene rubber blends in the presence and absence of a nanoclay
Authors: Razavi‐Nouri Mohammad , Naderi Ghasem , Parvin Ali , Ghoreishy Mir Hamid Reza
Published: March 2011

A thermoplastic elastomer (TPE) nanocomposite based on polypropylene (PP), acrylonitrile–butadiene rubber (NBR), and a nanoclay (NC) was prepared in a laboratory mixer with a 54/40/6 weight ratio. The effects of NC on the thermal properties, crystalline structure, and phase morphology of the TPE nanocomposite were studied in this work. The results obtained from the nonisothermal crystallization of PP, PP/NBR, and PP/NBR/NC, which was carried out with differential scanning calorimetry, revealed that the overall rate of crystallization of PP decreased with the addition of NBR to PP and increased when NC was incorporated into the nanocomposite. In addition, the crystallite size distribution was more uniform for the PP phase crystallized in the nanocomposite versus the PP itself. Also, although the PP in the reference blend (PP/NBR) crystallized only in the α form, the crystalline structure of the PP incorporated into the nanocomposite was a mixture of α‐ and γ‐crystalline forms. The effects of NC on the phase morphology of PP/NBR blends prepared with three different cooling methods (quenching in liquid nitrogen, cooling between two metal plates at room temperature, and molding at a high temperature in a hot press) were studied. For the samples quenched in liquid nitrogen or cooled between metal plates, a particulate–cocontinuous morphology formed. However, for the samples prepared under a hot press, a laminar‐like morphology was observed. In all three cases, a similar particulate–cocontinuous morphology formed for the reference blend, but the rubber inclusions were always smaller than those of the TPE nanocomposite. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Passivity‐based control for large‐signal stability of high‐order switching converters
Authors: Leyva R. , Olalla C. , Queinnec I. , Tarbouriech S. , Alonso C. , Martinez‐Salamero L.
Published: March 2011

This article presents a new passivity‐based control law that stabilizes the output voltage of a high‐order DC‐DC converter. Such nonlinear control law assures robust large‐signal stability, provides zero steady‐state error despite uncertainty in converter parameters and has enough degree of freedom to satisfy the usual transient specifications of DC‐DC converters. This new integral control is derived in three steps. First, a static law is obtained. Second, a positive semidefinite storage function is synthesized to guarantee zero steady‐state error of the output voltage. Finally, the storage functions of the first two steps are combined to derive the new control law for high‐order DC‐DC converters.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Development of waxy cassava with different Biological and physico‐chemical characteristics of starches for industrial applications
Authors: Zhao Shan‐Shan , Dufour Dominique , Sánchez Teresa , Ceballos Hernan , Zhang Peng
Published: March 2011

The quality of cassava starch, an important trait in cassava breeding programs, determines its applications in various industries. For example, development of waxy (having a low level of amylose) cassava is in demand. Amylose is synthesized by granule‐bound starch synthase I (GBSSI) in plants, and therefore, down‐regulation ofGBSSIexpression in cassava might lead to reduced amylose content. We produced 63 transgenic cassava plant lines that express hair‐pin dsRNAs homologous to the cassavaGBSSIconserved region under the control of the vascular‐specific promoter p54/1.0 from cassava (p54/1.0::GBSSI‐RNAi) or cauliflower mosaic virus (CaMV) 35S (35S::GBSSI‐RNAi). After the screening storage roots and starch granules from field‐grown plants with iodine staining, the waxy phenotype was discovered: p54/1.0::GBSSI‐RNAi line A8 and 35S::GBSSI‐RNAi lines B9, B10, and B23. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis showed that there was no detectable GBSSI protein in the starch granules of plants with the waxy phenotype. Further, the amylose content of transgenic starches was significantly reduced (<5%) compared with the level in starch granules from the wild‐type (about 25%). The inner structure of the waxy starch granules differed from that of the untransformed ones, as revealed by transmission electron microscopy analysis as well as morphological changes in the iodine–starch complex. Endothermic enthalpy was reduced in waxy cassava starches, according to differential scanning calorimeter analysis. Except B9, all waxy starches displayed the A‐type X‐ray diffraction pattern. Amylogram patterns of the waxy cassava starches were analyzed using a rapid viscosity analyzer and found to have increased values for clarity, peak viscosity, gel breakdown, and swelling index. Setback, consistency, and solubility were notably reduced. Therefore, waxy cassava with novel starch in its storage roots was produced using the biotechnological approach, promoting its industrial utilization. Biotechnol. Bioeng. 2011; 108:1925–1935. © 2011 Wiley Periodicals, Inc.
Bioproduction of butanol in bioreactors: New insights from simultaneous in situ butanol recovery to eliminate product toxicity
Authors: Mariano Adriano Pinto , Qureshi Nasib , Filho Rubens Maciel , Ezeji Thaddeus Chukwuemeka
Published: March 2011

Simultaneous acetone butanol ethanol (ABE) fermentation by Clostridium beijerinckii P260 and in situ product recovery was investigated using a vacuum process operated in two modes: continuous and intermittent. Integrated batch fermentations and ABE recovery were conducted at 37°C using a 14‐L bioreactor (7.0 L fermentation volume) containing initial substrate (glucose) concentration of 60 g/L. The bioreactor was connected in series with a condensation system and vacuum pump. Vacuum was applied continuously or intermittently with 1.5 h vacuum sessions separated by 4, 6, and 8 h intervals. A control ABE fermentation experiment was characterized by incomplete glucose utilization due to butanol toxicity to C. beijerinckii P260, while fermentation coupled with in situ recovery by both continuous and intermittent vacuum modes resulted in complete utilization of glucose, greater productivity, improved cell growth, and concentrated recovered ABE stream. These results demonstrate that vacuum technology can be applied to integrated ABE fermentation and recovery even though the boiling point of butanol is greater than that of water. Biotechnol. Bioeng. 2011; 108:1757–1765. © 2011 Wiley Periodicals, Inc.
An anatomic study using three‐dimensional reconstruction for pterygopalatine fossa infiltration via the greater palatine canal
Authors: Hwang Se Hwan , Seo Jae Hyun , Joo Young Hoon , Kim Byung Guk , Cho Jin Hee , Kang Jun Myung
Published: March 2011

The pterygopalatine fossa (PPF) is accessed via the greater palatine canal (GPC) in an attempt to reduce bleeding during paranasal sinus surgery. This study aims to investigate the anatomy of the greater palatine foramen (GPF), GPC, and the PPF, with reference to PPF infiltration using three‐dimensional reconstruction of computer tomographic (CT) scan measurements. The CT scans of 50 patients were retrospectively evaluated. The morphology of the GPF, GPC, and the PPF was assessed in a three‐dimensional model. The thickness of the mucosa over the GPF was evaluated in the parasagittal plane. The mean length of the GPC was 13.8 ± 2.0 mm, and the mean height of the PPF was 21.0 ± 3.4 mm. The mean angles of the GPC in relation to the hard palate and the PPF were 67.4° ± 6.9° and 159.8° ± 7.1°, respectively. The GPF was 16.2 ± 1.3 mm lateral to the sagittal plane of the posterior nasal spine (PNS) and 6.1 ± 1.7 mm anterior to the coronal plane of the PNS. The mean volume of the PPF was 1039.9 ± 280.0 mm3. The mean thickness of the mucosa overlying the GPF was 10.7 ± 1.8 mm. We recommend that the PNS may be used as the bony landmark to locate the position of the GPF during PPF infiltration. The needle delivering the anesthetic should be bent 25 mm from the tip at a 45° angle, and a 1‐ml injection of anesthetic should be administered in adults. Clin. Anat. 24:576–582, 2011. © 2011 Wiley‐Liss, Inc.
Accessory spleens at autopsy
Authors: Unver Dogan Nadire , Uysal Ismihan Ilknur , Demirci Serafettin , Dogan Kamil Hakan , Kolcu Giray
Published: March 2011

Accessory spleens (AS) may be formed during embryonic development when some of the cells from the developing spleen are deposited along the path from the midline, where the spleen forms, over to its final location on the left side of the abdomen. An accessory spleen is usually near the spleen's hilum, but it may be embedded partly or wholly in the tail of the pancreas. The aim of this study was to investigate the incidence and distribution of AS during routine forensic autopsies. AS were investigated in 720 consecutive autopsy cases. Fifty‐four AS were found in 48 (6.7%) cases. AS were found in hilum of the main spleen in 28 cases, the great omentum in 13 cases, the pancreas in 5 cases, and the pelvis in 2 cases. There were two AS in two cases and three AS in another two cases. Awareness of the possible presence of AS is important because when splenectomy is performed for some conditions such as immune thrombocytopenic purpura, failure to remove the AS may result in the failure of the condition to resolve. Additionally, during medical imaging, AS may be confused for enlarged lymph nodes or neoplastic growths. In conclusion, autopsy series are useful for determining the incidences and the other features of AS in different populations, in addition to those studies using CT scans and those studies obtained during laparoscopic or open surgeries. Clin. Anat. 24:757–762, 2011. © 2011 Wiley‐Liss, Inc.
Myo‐InositolTrisPyroPhosphate Treatment Leads to HIF‐1α Suppression and Eradication of Early Hepatoma Tumors in Rats
Authors: Aprahamian Marc , Bour Gaétan , Akladios Chérif Y. , Fylaktakidou Konstantina , Greferath Ruth , Soler Luc , Marescaux Jacques , Egly Jean‐Marc , Lehn Jean‐Marie , Nicolau Claude
Published: March 2011

Myo‐inositol trispyrophosphate (ITPP), a synthetic allosteric effector of hemoglobin, increases the regulated oxygen‐releasing capacity of red blood cells (RBCs), leading to suppression of hypoxia‐inducible factor 1α (HIF‐1α) and to down‐regulation of hypoxia‐inducible genes such as vascular endothelial growth factor (VEGF). As a consequence, tumor growth is markedly affected. The effect of weekly intravenous injection of ITPP on an orthotopic, syngenic rat hepatocellular carcinoma (HCC) model was compared to that for untreated animals and animals subjected to conventional Doxorubicin chemotherapy. The longitudinal examination of HCC was performed by microCT imaging, and the cellular and molecular changes were evaluated by histology and Western blotting analysis of HIF‐1α, VEGF, and caspase‐3 gene expression in the tumor and in the surrounding liver. Hematologic impact was evaluated by blood cell‐count measurement and determination of P50 (oxygen partial pressure for a 50 % oxygen saturation of hemoglobin). The HCC evaluation by microCT revealed a high potency of ITPP for tumor growth inhibition, thus allowing long‐term survival and even cure of almost all the treated animals. The P50 value of hemoglobin in RBCs underwent a shift of 30 % following ITPP injection. Under these conditions, HIF‐1α activity was strongly decreased, VEGF expression was down‐regulated, and apoptosis was induced in HCC and surrounding liver cells, as indicated by Caspase‐3 expression. ITPP did not affect hematologic parameters during treatment. The observations of in vivo tumor eradication suggest a significant clinical potential for ITPP in cancer therapy.
STEM HAADF Tomography of Molybdenum Disulfide with Mesoporous Structure
Authors: Nan Feihong , Song Chaojie , Zhang Jiujun , Hui Rob , Chen Jinwen , Fairbridge Craig , Botton Gianluigi A.
Published: March 2011

A highly ordered mesoporous molybdenum disulfide has been developed for catalysis in heavy oil refining. The morphology, structure, and composition of the material have been systematically characterized with advanced electron microscopy techniques. Scanning transmission electron microscopy with high‐angle annular dark field tomography has been used to investigate the porous structure to give spatial information on the nanometre scale, and offer a direct view of individual porous particles in three‐dimensions. The pore‐size distribution, connectivity of the pores, and the mesoporous surface area have also been analyzed and offer useful information towards catalyst design.
The direct oxidation of hydrogen sulphide over activated carbons prepared from lignite coal and biochar
Authors: Azargohar R. , Dalai A. K.
Published: March 2011

Physically (steam) and chemically (KOH) activated carbons prepared from Luscar coal and biochar were used for removal of low concentrations of hydrogen sulphide (1 mol%) in methane. A modification method including acid treatment and thermal desorption in an inert atmosphere was used and the effects of this modification on the porous structure, surface chemistry, and ash content were studied. It increased total pore volume of activated carbons prepared from coal and biochar by 43% and 11%, respectively. Acid treatment changed the surface chemistry of activated carbons. Also, thermal desorption removed most of the acidic groups, especially carboxylic groups. The break‐through times corresponding to 80% removal of H2S using modified activated carbons prepared from coal and biochar were increased to 102 and 131 min, respectively. Also, the production of SO2 as an undesirable by‐product was less than 1.9% of H2S fed into the reactor.
Solids suspension with angle‐mounted agitators in unbaffled vessels
Authors: Myers Kevin J. , Herr Jonathan P. , Janz Eric E.
Published: March 2011

Solids suspension using an angle‐mounted axial‐flow impeller in an unbaffled tank relies on proper placement of the impeller in the vessel such that swirling flow does not occur. Even with proper placement, the just‐suspended speed of an angle‐mounted agitator is often 75% higher than with vertical mounting on the centreline in a baffled tank, leading to torque and power requirements that average more than twice and five times higher, respectively. Angle‐mounted turbulent power numbers of axial‐flow impellers are generally similar to, but lower than the corresponding power numbers with vertical mounting on the centreline of a baffled tank.
Removal of strontium and barium from aqueous solutions by adsorption onto expanded perlite
Authors: Torab‐Mostaedi Meisam , Ghaemi Ahad , Ghassabzadeh Hamid , Ghannadi‐Maragheh Mohammad
Published: March 2011

The adsorption of strontium and barium from aqueous solution onto expanded perlite (EP) has been investigated as a function of pH, contact time, adsorbent dosage, and temperature. Sorption experiments indicated that the sorption capacity was dependent on operating variables and the process was strongly pH‐dependent. Equilibrium isotherm data were analysed using Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models. The adsorption was well described by Langmuir isotherm model. The maximum adsorption capacity was found to be 1.14 and 2.486 mg/g for Sr (II) and Ba (II) from the Langmuir isotherm model at 20°C, respectively. Two simplified kinetic models viz. pseudo‐first‐order and pseudo‐second‐order models were tested to describe the adsorption process. The kinetic data indicated that adsorption fitted well with the pseudo‐second‐order kinetic model. Using the equilibrium constant value obtained at four (20, 30, 40, and 50°C) different temperatures, the thermodynamic parameters of the adsorption (ΔG°, ΔH°, and ΔS°) were also determined. The results showed that the adsorption of Sr (II) and Ba (II) ions on EP was exothermic and spontaneous.
Wettability of porous two‐dimensional ZnO nanocrystal films
Authors: Shi D. , Wang X. C. , Yao Z. W. , Liu F. , Zhang X. B. , Cheng J. P.
Published: March 2011

Large‐scale two‐dimensional ZnO nanocrystal films on aluminum substrate were fabricated by a one‐step hydrothermal method under mild conditions, where all the ZnO nanocrystals had a lamellar structure generally perpendicular to the substrates and formed network‐like porous configurations. The morphologies of the films were dependent on both the reaction temperature and concentration of zinc. The wettability of the ZnO films was assessed by measuring the water contact angle without any surface functionalisation. The porous structures of the as‐prepared films could effectively enhance its hydrophobicity and the water contact angle ranged from 40° to 135° depending on the surface morphology and the arrangement of ZnO planes, indicating a simple and promising route to make aluminum surface waterproof and even self‐cleaning. The hydrophobic ZnO surface could be switched to hydrophilic state by UV irradiation.
Ab initio Study of Electronic Structure and Properties of Crystalline of 1,5‐Diamino‐1,2,3,4‐tetrazole
Authors: Shang Jing , Zhang Jianguo , Zhang Tonglai , Shu Yuanjie , Zhang Shaowen , Huang Huisheng
Published: March 2011

Density functional method was applied to study 1,5‐diamino‐1,2,3,4‐tetrazole (DAT, CH4N6) in both gaseous and bulk states. The banding and electronic structures of crystalline have been investigated at DFT‐B3LYP/ 6‐311G** level of theory. Relaxed crystal structure compares well with experimental data. The light fluctuation of the frontier orbital, which is mainly formed by atomic orbital of N(4) (heterocycle), is the most reactive part of the molecule, which is in good agreement with the experimental results. The energy gap is 9.035 eV, which indicates that DAT is an insulator. The distribution of electrostatic potential is uniform, indicating DAT is insensitive. The charge density of the intermolecular regions in the plane is not overlaid, indicating that the intermolecular interaction between the neighboring molecules along this direction in the bulk is very weak. The overlap populations of N(1)N(2) bonds are much less than those of other bonds, therefore the N(1)N(2) bonds first rupture by external stimuli.
Crystal Structure and Theoretical Calculation of 1,4‐Bis‐(1‐ferrocenesulfonyl‐2‐benzimidazolyl) Butane
Authors: Yue Kefen , Zhuo Fei , Zhai Gaohong , Hou Lei , Hou Yibo , Yin Bing , Wang Yaoyu
Published: March 2011

A N,N′‐bisferrocenesulfonyl bisbenzimidazole compound 1,4‐bis(1‐ferrocenesulfonyl‐2‐benzimidazolyl) butane was prepared. Its crystal structure was determined. The crystal belongs to triclinic with space group P‐1 and a=0.87241(13) nm, b=0.97553(15) nm, c=1.4120(2) nm, and α=83.041(2) °, β=72.454(2)°, γ=69.732(2)°, the unit cell volume V=1.0746(3) nm3, the molecule number in one unit cell Z=1, the absorption coefficient μ=1.191 mm−1, the calculated density Dc=1.584 g/cm3. The theoretical investigation of the compound as a structure unit was fully optimized by B3LYP/6‐31G method in Gaussian 03 package, and the most stable structure of the compound in theory was obtained. The two results were compared. The optimized structure was in accordance with the crystal structure in the main, suggesting that the molecular geometry optimization of the structures was reliable and the calculation method used was reliable. The distribution of atomic charges and the energy, and composition of frontier molecular orbits were analyzed. Thermal analysis indicated that it is stable before melting.
Highly Efficient Hydrogenation of Methyl Propionate to Propanol over Hydrous Zirconia Supported Ruthenium
Authors: Fan Guangyin , Zhou Yafen , Fu Haiyan , Ye Xiaoli , Li Ruixiang , Chen Hua , Li Xianjun
Published: March 2011

Hydrous zirconia supported ruthenium catalyst Ru/ZrO2·xH2O, prepared by co‐precipitating ruthenium trichloride and zirconium oxychloride with ammonia, was able to catalyze efficiently methyl propionate to propanol under the mild conditions. In aqueous system, the propanol yield of >99% was achieved under the conditions of reaction temperature of 150°C and hydrogen pressure of 5.0 MPa, while in non‐aqueous system the maximum propanol yield was only 47.0%. FTIR spectra and hydrogenation results indicated that the high catalytic performance of Ru/ZrO2·xH2O in aqueous phase results from the cooperation effect between water as a solvent and hydroxyl groups on the surface of carrier.
Synthesis, Crystal Structure and Optical Properties of Europium Trifluoroacetate Complexes with 1,10‐Phenanthroline and 2,2′‐Bipyridine
Authors: She Jiangbo , Cui Xiaoxia , Hou Chaoqi , Gao Chao , Wei Wei , Peng Bo
Published: March 2011

Two europium trifluoroacetate complexes, Eu(CF3COO)3·phen (1) and Eu(CF3COO)3·bpy (2) (where phen=1,10‐phenanthroline, bpy=2,2′‐bipyridine), were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy (FT‐IR), photoluminescence (PL) spectroscopy and thermogravimetric analysis (TA). Single‐crystal X‐ray structure has been determined for the complex [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH. The crystal structure of [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH shows that two different coordination styles with europium ions coexist in the same crystal and have entirely different coordination geometries and numbers. This crystal can be considered as an 1:1 adduct of [Eu(CF3COO)3·(Phen)2·H2O]·EtOH (9‐coordination part) and Eu(CF3COO)3·phen·H2O (8‐coordination part). The excitation spectra of the two complexes demonstrate that the energy collected by "antenna ligands" is transferred to Eu3+ ions efficiently. The room‐temperature PL spectra of the complexes are composed of the typical Eu3+ ions red emission, due to transitions between 5D0→7FJ(J=0→4). The lifetimes of 5D0 of Eu3+ in the complexes were examined using time‐resolved spectroscopic analysis, and the lifetime values of Eu(CF3COO)3·phen and Eu(CF3COO)3·bpy were fitting with bi‐exponential (2987 and 353 µs) and monoexponential (3191 µs) curves, respectively. In order to elucidate the energy transfer process of the europium complexes, the energy levels of the relevant electronic states had been estimated. The thermal analyses indicate that they are all quite stable to heat.
Investigation of the Effect of Metallic Lewis Acid on the Nitrolysis of [3,7‐Diacetyl‐1,3,5,7‐tetraazabicyclo(3.3.1)‐nonane] and Hexamine
Authors: Shi Liangwei , Yu Menglong , Zhang Yazhu , Qin Guangming , Lü Jian , Zhao Gang
Published: March 2011

The effect of metallic ions on the nitrolysis of DAPT [3,7‐diacetyl‐1,3,5,7‐tetraazabicyclo(3.3.1)nonane] and HA (hexamine) was investigated by experimental and theoretical approaches. The combinatorial reagent, M(NO−3)n/Ac2/NH4NO3 (M=Mg2+, Cu2+, Pb2+, Bi3+, Fe3+ and Zr4+), was found to be efficient in the experiment of the nitrolysis of DAPT. A key intermediate during the nitrolysis of DAPT was detected by 1H NMR. The formation mechanism of the intermediate was proposed and analyzed. Some discrepant results for the nitrolysis of DAPT and HA catalyzed by different metallic nitrates were explained based on hard‐soft and acid‐base principle and stabilized energy of ion‐complex. From the latter point of view, some cations with high polarizable ligands, e.g., OSO2CF3−, (CF3SO2)2N−, and (C4F9SO2)2N−, can increase the yields. Two newly designed catalysts, Cu[(CF3SO2)2N]2 and Cu[(C4F9SO2)2N]2, were tested to be highly efficient.
An Efficient Synthesis of 3‐Alkyl‐2‐alkyliminooxazolidin‐4‐one via a Domino Reaction
Authors: Liu Yongwei , Li Zhengning , Jiang Lan , Zheng Aijun
Published: March 2011

3‐Alkyl‐2‐alkyliminooxazolidin‐4‐ones were prepared from a copper‐catalyzed domino intermolecular nucleophilic addition of α‐hydroxy‐(or mecapto) carboxylic acid ester to carbodiimide and a followed nucleophilic substitution of the formed amino group to carboxylic acid ester. The reactions could be performed under convenient conditions and good yields were achieved in most cases.
Carbohydrate Coated Polymer Particles: Preparation and Protein‐binding Studies
Authors: Sun Zicai , Wei Zheng , Chen Jianjun , Wei Kemei
Published: March 2011

A facile and effective organic synthesis route was provided for preparation of the carbohydrate coated polymer small particles. First, amino‐activated particles were prepared from PAN (polyacrylonitrile) by the heterogeneous cross‐linking method, then the amino groups on the particle were converted into hydrazide groups by N‐alkylation and hydrazine activation, meanwhile the length of linker was prolonged to the designed value. FTIR (Fourier Transform Infrared Spectroscopy) was used to study the reactions in the synthesis steps and to optimize part of the synthesis conditions. Two carbohydrates (maltose and heparin) were then directly coupled to the hydrazide‐activated particles in a relative high yield, the obtained particles were used to interact with BSA (bovine serum albumin) and typical heparin‐binding proteins. All of these particles had some nonspecific interactions with proteins and heparin coated particles showed additional strong binding ability with the heparin‐binding proteins. Data also showed that a longer linker length not only weakened nonspecific interaction but also increased the specific binding ability. As the carbohydrate coated particles are independent, flexible and easily detectable, they should be good acceptors for the diverse bioactive studies of carbohydrates.
Grafting of 4‐Vinyl Pyridine onto Nylon‐6 Initiated by Redox System
Authors: Zhou Jian , Bai Libin , Qin Hong , Liu Yinghai
Published: March 2011

The graft copolymerization of 4‐vinyl pyridine (4VP) onto nylon‐6 (PA6) was studied by using potassium diperiodatonickelate(IV) (DPN)‐PA6 redox system in alkaline medium. The structures of graft copolymers were confirmed by Fourier transfer infrared spectroscopy (FTIR) and X‐ray diffraction. The properties of graft copolymers were investigated by thermogravimetric analysis (TGA). A mechanism was proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, the ratio of 4VP to PA6, pH as well as reaction temperature and time were investigated. Graft copolymers with high grafting efficiency (>95%) were obtained, which indicated that DPN‐PA6 redox system is an efficient initiator for this graft copolymerization. The quaternized PA6‐g‐P4VP (QPAVP) was proved to be an excellent adsorbent to heavy metal ions.
Preparation of Novel Silica Nanoparticles with Controllable Fluorescence Intensity from Porphyrin‐Bridged Silsesquioxane
Authors: Guo Ximing , Guo Bin , Sun Xuemei , Zhang Qingyuan , Shi Tongshun
Published: March 2011

A method for the fabrication of an improved class of controllable fluorescence intensity, highly sensitive and photostable porphyrin doped silica nanoparticles (PDSNPs) was demonstrated. The fluorescence intensity of PDSNPs could be controlled by finely tuning self‐dissociated time of the precursor of porphyrin‐bridged silsesquioxane. Porphyrin was well dispersed into the silica matrix due to the covalent attachment in the system, thus entirely avoiding the porphyrin leakage and fluorescence quenching effects. The resultant PDSNPs with a narrow size‐distributed region and a regular spherical structure can be attained.
Effect of Organic Additives on the Performance of Nano‐sized Ru‐Zn Catalyst
Authors: Sun Haijie , Chen Zhihao , Guo Wei , Zhou Xiaoli , Liu Zhongyi , Liu Shouchang
Published: March 2011

A novel Ru‐Zn catalyst was prepared by coprecipitation. The catalyst was characterized by XRF, XRD and TEM. The effects of organic additives on the performance of the Ru‐Zn catalyst for benzene selective hydrogenation to cyclohexene were investigated. The results showed that the catalyst was composed of Ru and Zn in molar ratio of 33.8:1, and the most probable value of the Ru crystallite size in the catalyst was 5.1 nm. The modification of Ru with Zn and the small size effect were the main cause why the catalyst exhibited the high activity and the excellent cyclohexene selectivity. When PEG (polyethylene glycol) was used as an additive, the activity of the catalyst decreased, and the cyclohexene selectivity increased with the increase of the PEG molecular weight. With the addition of PEG‐20000, a cyclohexene selectivity of 78.9% at a benzene conversion of 68.7% and a maximum cyclohexene yield of 61.4% were obtained. With diethanolamine and triethanolamine as additives, cyclohexene yields were as high as 58.9% and 58.2%, respectively.
Target‐Selective Drug Delivery through Liposomes Labeled with Oligobranched Neurotensin Peptides
Authors: Falciani Chiara , Accardo Antonella , Brunetti Jlenia , Tesauro Diego , Lelli Barbara , Pini Alessandro , Bracci Luisa , Morelli Giancarlo
Published: March 2011

The structure and the in vitro behavior of liposomes filled with the cytotoxic drug doxorubicin (Doxo) and functionalized on the external surface with a branched moiety containing four copies of the 8–13 neurotensin (NT) peptide is reported. The new functionalized liposomes, DOPC‐NT4Lys(C18)2, are obtained by co‐aggregation of the DOPC phospholipid with a new synthetic amphiphilic molecule, NT4Lys(C18)2, which contains a lysine scaffold derivatized with a lipophilic moiety and a tetrabranched hydrophilic peptide, NT8–13, a neurotensin peptide fragment well known for its ability to mimic the neurotensin peptide in receptor binding ability. Dynamic light scattering measurements indicate a value for the hydrodynamic radius (RH) of 88.3±4.4 nm. The selective internalization and cytotoxicity of DOPC‐NT4Lys(C18)2 liposomes containing Doxo, as compared to pure DOPC liposomes, were tested in HT29 human colon adenocarcinoma and TE671 human rhabdomyosarcoma cells, both of which express neurotensin receptors. Peptide‐functionalized liposomes show a clear advantage in comparison to pure DOPC liposomes with regard to drug internalization in both HT29 and TE671 tumor cells: FACS analysis indicates an increase in fluorescence signal of the NT4‐liposomes, compared to the DOPC pure analogues, in both cell lines; cytotoxicity of DOPC‐NT4Lys(C18)2‐Doxo liposomes is increased four‐fold with respect to DOPC‐Doxo liposomes in both HT29 and TE671 cell lines. These effects could to be ascribed to the higher rate of internalization for DOPC‐NT4Lys(C18)2‐Doxo liposomes, due to stronger binding driven by a lower dissociation constant of the NT4‐liposomes that bind the membrane onto a specific protein, in contrast to DOPC liposomes, which approach the plasma membrane unselectively.
From β‐Amino‐γ‐sultone to Unusual Bicyclic Pyridine and Pyrazine Heterocyclic Systems: Synthesis and Cytostatic and Antiviral Activities
Authors: de Castro Sonia , Familiar Olga , Andrei Graciela , Snoeck Robert , Balzarini Jan , Camarasa María‐José , Velázquez Sonsoles
Published: March 2011

Herein we describe the first successful application of the β‐amino‐γ‐sultone system as an intermediate for the synthesis of hitherto virtually unknown 3H‐[1,2]‐oxathiole [4,3‐b]pyridine and pyrazine 1,1‐dioxide bicyclic heterocyclic systems. All novel compounds were evaluated for their antiviral and cytostatic activities. Compounds 3 a, 15 a, and 21 a inhibited HIV‐1‐induced cytopathicity. Compound 7 showed remarkable cytostatic activity, and can be regarded as a potential antitumor candidate for further exploration.
Retracted: Up‐regulation of microRNA‐145 promotes differentiation by repressing OCT4 in human endometrial adenocarcinoma cells
Authors: Wu Yanjing , Liu Shupeng , Xin Hong , Jiang Jing , Younglai Edward , Sun Shuhan , Wang Huilan
Published: March 2011

Retraction: Yanjing Wu, Shupeng Liu, Hong Xin, Jing Jiang, Edward Younglai, Shuhan Sun, and Huilan Wang. Up‐Regulation of MicroRNA‐145 Promotes Differentiation by Repressing OCT4 in Human Endometrial Adenocarcinoma Cells. Cancer 2011;117:3989‐3998.

The above article, published online on March 1, 2011 in Wiley Online Library ( https://doi.org/10.1002/cncr.25944) has been retracted by agreement between the journal’s Editor‐in‐Chief, Dr. Suresh S. Ramalingam, and Wiley Periodicals LLC. The retraction has been agreed upon following concerns raised by a third party (1) regarding flaws and inconsistencies between the results presented and the experimental methods described. In addition, evidence of image manipulation was also detected. As a result, the Editor‐in‐Chief considers the conclusions of this article to be invalid.

Park Y, West RA, Pathmendra P, Favier B, Stoeger T, Capes‐Davis A, Cabanac G, Labbé C, Byrne JA. “Identification of human gene research articles with wrongly identified nucleotide sequences.” Life Sci Alliance. 2022 Jan 12;5(4):e202101203. doi: 10.26508/lsa.202101203. Print 2022 Apr.
Comparison of radiation‐induced fatigue across 3 different radiotherapeutic methods for early stage breast cancer
Authors: Taunk Neil K. , Haffty Bruce G. , Chen Sining , Khan Atif J. , Nelson Carl , Pierce Dorothy , Goyal Sharad
Published: March 2011

BACKGROUND:

Radiation‐induced fatigue is a common side effect of breast cancer radiotherapy (RT). This study compares the induction and persistence of radiation‐induced fatigue in accelerated partial breast irradiation (APBI), accelerated hypofractionated RT, and standard whole breast RT.

METHODS:

Eighty patients were treated with a novel, 3‐week accelerated regimen with 333 centigrays (cGy) for 15 fractions to 4995 cGy; of these, 45 were treated using APBI, whereas 35 patients were treated using accelerated hypofractionated RT. These patients were matched with patients receiving 200 cGy for 30 fractions using standard whole breast irradiation. Fatigue score, using Common Terminology Criteria for Adverse Events version 4.0, was obtained at 5 time points: consultation before RT, first on‐treatment visit, halfway through treatment, last on‐treatment visit, and first follow‐up.

RESULTS:

Maximum fatigue and average fatigue since treatment were calculated. Maximum fatigue was 1.5, 2.4, and 2.3, and average fatigue was 0.46, 0.81, and 0.92 for the APBI, accelerated hypofractionated RT, and standard whole breast RT groups, respectively. The accelerated schedules did not have significantly less fatigue than standard whole breast RT at first on‐treatment visit. Maximum fatigue in APBI was reduced compared with standard whole breast RT. Accelerated hypofractionated RT had fatigue trajectory similar to standard whole breast RT. Multivariate analysis found that increased age and whole breast treatment are associated with more fatigue. Chemotherapy, hormone therapy, race, and T stage were not significant predictors of maximum fatigue. Results were similar for average fatigue, except that magnitudes were smaller.

CONCLUSIONS:

Field sizes and age in breast RT were positively associated with maximum radiation‐induced fatigue. Accelerated hypofractionated RT and standard whole breast RT had similar fatigue trajectories compared with APBI, which reduced fatigue at all times. Cancer 2011. © 2011 American Cancer Society.
Population‐level comparative effectiveness of laparoscopic versus open radical nephrectomy for patients with kidney cancer
Authors: Tan Hung‐Jui , Wolf J. Stuart , Ye Zaojun , Wei John T. , Miller David C.
Published: March 2011

BACKGROUND:

Because there is limited population‐based evidence supporting the comparative effectiveness of laparoscopic radical nephrectomy (LRN) after its widespread adoption, we compared trends in hospital‐based outcomes among patients with kidney cancer treated with LRN or open radical nephrectomy (ORN).

METHODS:

Using linked SEER‐Medicare data, the authors identified patients with kidney cancer who were treated with LRN or ORN from 2000 through 2005. The authors measured 4 primary outcomes: intensive care unit (ICU) admission, prolonged length of stay, 30‐day hospital readmission, and in‐hospital mortality. The authors then estimated the association between surgical approach and each outcome, adjusting for patient demographics, tumor characteristics, and year of surgery.

RESULTS:

The authors identified 2108 (26%) and 5895 (74%) patients treated with LRN and ORN, respectively. Patients treated with LRN were more likely to be white, female, of higher socioeconomic position, and to have tumor sizes of ≤4 cm (all P < .05). The adjusted probability of ICU admission and prolonged length of stay was 41% and 46% lower, respectively, for patients undergoing LRN (P < .001). Although uncommon for both groups, the adjusted probability of in‐hospital mortality was 51% higher (2.3% vs 1.5%, P = .04) for patients treated with a laparoscopic approach.

CONCLUSIONS:

At a population level, patients treated with LRN have a lower likelihood of ICU admission and prolonged length of stay, supporting the convalescence benefits of laparoscopy. In‐hospital mortality, however, was higher among patients treated with LRN. The latter finding suggests a potentially unanticipated consequence of this technique and highlights the need for long‐term monitoring during and after the widespread adoption of new surgical technologies. Cancer 2011;. © 2011 American Cancer Society.
Performance of p16INK4a immunocytochemistry as a marker of anal squamous intraepithelial lesions
Authors: Tramujas da Costa e Silva Ivan , Coelho Ribeiro Michelle , Santos Gimenez Felicidad , Dutra Ferreira Junia Raquel , Galvao Renata Silva , Vasco Hargreaves Paula Emanuelle , Gonçalves Daumas Pinheiro Guimaraes Adriana , de Lima Ferreira Luiz Carlos
Published: March 2011

BACKGROUND:

Protein p16INK4a immunocytochemistry (ICCp16) has the potential to reveal lesions at risk of progression to anal cancer. This study examined measures of diagnostic validity of ICCp16 in HIV‐positive patients treated at the Tropical Medicine Foundation of Amazonas in the coloproctology outpatient clinic.

METHODS:

One hundred ninety HIV‐positive patients were consecutively enrolled in 2007 and 2008. All patients underwent anal cytologic sampling to perform ICCp16 in conventional and GluCyte (Synermed International, Westfield, Indiana and S¸ao Paulo, Brazil) smears and also for genotyping of human papillomavirus (HPV). Patients were then subjected to anal biopsies monitored by high‐resolution anoscopy. Hematoxylin‐eosin and immunoperoxidase p16 (clone 6H12) stains were performed in slides with biopsied and cytological specimens, respectively. HPV genotyping on anal scrapings was performed by a polymerase‐chain reaction (PCR)‐based method. The immunochemical findings were compared with histopathological and PCR results in contingency tables and analyzed by nonparametric tests. Measures of diagnostic validity of ICCp16 were calculated. Statistical significance was set at P ≤ .5.

RESULTS:

There was no statistically significant association between the immunochemical results (conventional or GluCyte smears) and histopathological or HPV genotyping findings (P > .05). In the best scenario, ICCp16 presented 31% sensitivity and 81% specificity for the diagnosis of anal squamous intraepithelial lesion (ASIL) and 30% and 66%, respectively, for the diagnosis of infection with high‐risk HPV.

CONCLUSIONS:

There was no association between ICCp16 results and histopathological findings nor between ICCp16 and HPV genotyping. ICCp16 showed poor sensitivity and moderate specificity for the diagnosis of ASIL or high‐risk HPV. Cancer (Cancer Cytopathol) 2011. © 2011 American Cancer Society.
Intrinsic Mobility of Gaseous Cationic and Anionic Aggregates of Ionic Liquids
Authors: Lalli Priscila M. , Corilo Yuri E. , de Sa Gilberto F. , Daroda Romeu J. , de Souza Vanderlea , Souza Gustavo H. M. F. , Campuzano Iain , Ebeling Günter , Dupont Jairton , Eberlin Marcos N.
Published: March 2011

Travelling‐wave ion mobility mass spectrometry was used to measure the intrinsic mobility of a series of gaseous supra‐cation and supra‐anion aggregates of several ionic liquids. Close mobilities were observed in a T‐wave cell filled with helium at ca. 0.8 mbar for [(DAI)n+1(X)n]+ (DAI is the 1,3‐dialkylimidazolium cation and X is the anion) as compared to the respective anions [(DAI)n(X)n+1]− for n=0 to 9. The anomalous behavior reported before in the condensed phase seems therefore to be related to the unique structural organization of pure ionic liquids that provides both polar and non‐polar regions with directionality in which the anionic species are more retained than the cationic species in the salt network.