bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling and stress–strain characteristics of the mechanical properties of carbon‐nanotube‐reinforced poly(vinyl acetate) nanocomposites
Authors: Merijs Meri Remo , Bitenieks Juris , Kalnins Martins , Maksimov Robert 
Published: August 2011

AbstractPolymer/carbon nanotube (CNT) composites are one of the most perspective advanced materials developed in recent years. The properties of CNT‐reinforced polymer composites, however, strongly depend on structural aspects of the nanostructured filler and on its dispersion quality in a polymer matrix. Consequently, this research was devoted to the investigation of multiwalled‐CNT‐modified poly(vinyl acetate) (PVAc) composites with respect to the mechanical property dependence on some structural characteristics of CNTs. PVAc/CNT nanocomposites were obtained with a solution casting technique. The amount of CNTs was changed from 0.01 up to 2 wt %. The stress–strain characteristics of PVAc/CNT nanocomposites clearly revealed remarkable reinforcing effects of the CNT additions already at 0.01 wt %. At this CNT concentration, the elastic modulus (E) and tensile yield stress increased by 12.5 and 60%, respectively. Special attention was paid to the change of E with respect to some structural characteristics of CNTs. A corresponding mathematical model for the prediction of the elastic properties of CNT polymer nanocomposites is proposed, showing that elastic constants of the nanocomposites largely depend on the agglomeration of CNTs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Influence of the stacking sequence on the porosity in carbon fiber composites
Authors: Toscano C. , Vitiello C. 
Published: August 2011

AbstractSeveral composite laminate structures with different stacking sequences were manufactured to study how the special orientation of the fibers can influence the porosity distribution in the material. Different amounts of porosity were introduced into the laminate during autoclave curing through the application of pressures that differed from the prescribed one. All of the obtained structures were analyzed by ultrasonic inspection to measure the attenuation undergone by the signal through crossing within the material. Subsequently, the attenuation variations were associated with the induced porosity. The obtained results were corroborated by an estimation of the percentage of porosity introduced into the composites structures through the application of a standard method for density measurement. The results prove that there are stacking sequences much more subject to trap air with the consequent formation of the porosity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Poly(vinyl chloride)/CaCO3 nanocomposites: Influence of surface treatments on the properties
Authors: Bonadies Irene , Avella Maurizio , Avolio Roberto , Carfagna Cosimo , Errico Maria Emanuela , Gentile Gennaro 
Published: August 2011

AbstractPoly(vinyl chloride) (PVC)‐based nanocomposites containing calcium carbonate nanoparticles (CaCO3) were prepared. Different nanoparticle surface modifiers were selected and tested to promote matrix/filler interactions and, consequently, to obtain high‐ performance materials. In particular, the nanoparticles were modified with poly(acrylic acid) (PAA) and poly (butadiene‐co‐acrylonitrile‐co‐acrylic acid) (PBAA). For comparison, PVC‐based materials, with the addition of commercial neat and stearic acid modified CaCO3, were also prepared. The influence of CaCO3 and surface modifiers on the gelation, thermal properties, thermal stability, and mechanical properties of PVC was studied. The gelation time of the rigid PVC/CaCO3 composites decreased as a function of the percentage and surface treatment of CaCO3. Morphological analysis proved the effectiveness of PAA and PBAA as surface modifiers; they obtained for the corresponding materials a typical nanostructured morphology. A significant improvement in the PVC thermal stability was recorded with the addition of neat and stearic acid modified CaCO3. Finally, mechanical tests showed an increase in the flexural strength and toughness of PVC as a function of the nanoparticle surface modifier. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Interleukin‐17A induction of angiogenesis, cell migration, and cytoskeletal rearrangement
Authors: Moran Ellen M. , Connolly Mary , Gao Wei , McCormick Jennifer , Fearon Ursula , Veale Douglas J. 
Published: August 2011

AbstractObjectiveTo examine the ability of interleukin‐17A (IL‐17A) to stimulate angiogenesis, cell migration, and cytoskeletal rearrangement.MethodsThe effect of IL‐17A on microvascular tube formation and extracellular matrix invasion by human dermal endothelial cells (HDECs) was assessed using Matrigel matrix and Transwell Matrigel invasion chambers. IL‐17A–induced growth‐related oncogene α (GROα) and monocyte chemotactic protein 1 (MCP‐1) production in rheumatoid arthritis synovial fibroblasts (RASFs) and HDECs was measured by enzyme‐linked immunosorbent assay. IL‐17A–induced migration was assessed using peripheral blood mononuclear cell (PBMC) migration assays and wound‐repair scratch assays, with or without anti‐GROα and anti–MCP‐1 antibodies. Binding of β1 integrin receptors was assessed using integrin binding assays. Cytoskeletal assembly/disassembly in RASFs and HDECs were assessed by immunofluorescence staining for F‐actin. IL‐17A–induced cell migration and cytoskeletal disassembly were assessed in the presence of a Rac1 inhibitor (NSC23766). Rac1 activation following IL‐17 stimulation in the presence or absence of anti‐GROα, anti–MCP‐1, or IgG control was assessed by Rac GTPase pull‐down assays and Western blotting.ResultsIL‐17A significantly up‐regulated angiogenesis and endothelial cell invasion. It significantly induced GROα and MCP‐1 expression in RASFs. Migration of PBMCs, RASFs, and HDECs was induced by IL‐17A; these effects were blocked by anti‐GROα or anti–MCP‐1 antibodies. IL‐17A significantly up‐regulated β1 integrin receptor binding and induced cytoskeletal disassembly in RASFs and HDECs. Rac1 activation was directly induced by IL‐17A. IL‐17A–induced wound repair and actin rearrangement were inhibited by a pharmacologic inhibitor of Rac1 (NSC23766). Anti‐GROα or anti–MCP‐1 antibodies had no effect on IL‐17A–induced Rac1 activation.ConclusionIL‐17A induces angiogenesis, cell migration, and cell invasion, all of which are key processes in the pathogenesis of rheumatoid arthritis and ones that are mediated in part through chemokine‐ and cytoskeleton‐dependent pathways.
Antibacterial Agents and Cystic Fibrosis: Synthesis and Antimicrobial Evaluation of a Series of N‐Thiomethylazetidinones
Authors: Galletti Paola , Cocuzza Clementina E. A. , Pori Matteo , Quintavalla Arianna , Musumeci Rosario , Giacomini Daria 
Published: August 2011

AbstractThe increasing emergence of multidrug‐resistant microorganisms is one of the greatest challenges in the clinical management of infectious disease. New antimicrobial agents are therefore urgently required, particularly in the treatment of chronic and recurrent infections often associated with antibiotic‐resistant pathogens, as in the case of cystic fibrosis (CF) patients. This study reports the antibacterial activity of a series of monocyclic β‐lactams with an alkylidenecarboxyl chain or electron‐withdrawing groups such as 4‐OAc, 4‐SAc, and 4‐SO2Ph at the C4 position of the ring. N‐Unsubstituted and N‐thiomethyl derivatives were compared. A total of 33 azetidinones were tested for their activity against Gram‐positive and Gram‐negative bacterial clinical isolates. The combination of an N‐thiomethyl group and a benzyl ester on the 4‐alkylidene side chain were found to increase the potency against Gram‐positive bacteria. The N‐thiomethyl group clearly elevated the activity of 4‐acetoxyazetidinones relative to the corresponding NH derivatives. The most active compounds showed minimum inhibitory concentration (MIC) values of 4 and 8 mg L−1 against methicillin‐resistant Staphylococcus aureus isolated from pediatric patients with CF.
Casting a net on dendritic spines: The extracellular matrix and its receptors
Authors: Dansie Lorraine E. , Ethell Iryna M. 
Published: August 2011

AbstractDendritic spines are dynamic structures that accommodate the majority of excitatory synapses in the brain and are influenced by extracellular signals from presynaptic neurons, glial cells, and the extracellular matrix (ECM). The ECM surrounds dendritic spines and extends into the synaptic cleft, maintaining synapse integrity as well as mediating trans‐synaptic communications between neurons. Several scaffolding proteins and glycans that compose the ECM form a lattice‐like network, which serves as an attractive ground for various secreted glycoproteins, lectins, growth factors, and enzymes. ECM components can control dendritic spines through the interactions with their specific receptors or by influencing the functions of other synaptic proteins. In this review, we focus on ECM components and their receptors that regulate dendritic spine development and plasticity in the normal and diseased brain. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 71: 956‐981, 2011
Motoneuron programmed cell death in response to proBDNF
Authors: Taylor Anna R. , Gifondorwa David J. , Robinson Mac B. , Strupe Jane L. , Prevette David , Johnson James E. , Hempstead Barbara , Oppenheim Ronald W. , Milligan Carolanne E. 
Published: August 2011

AbstractMotoneurons (MN) as well as most neuronal populations undergo a temporally and spatially specific period of programmed cell death (PCD). Several factors have been considered to regulate the survival of MNs during this period, including availability of muscle‐derived trophic support and activity. The possibility that target‐derived factors may also negatively regulate MN survival has been considered, but not pursued. Neurotrophin precursors, through their interaction with p75NTR and sortilin receptors have been shown to induce cell death during development and following injury in the CNS. In this study, we find that muscle cells produce and secrete proBDNF. ProBDNF through its interaction with p75NTR and sortilin, promotes a caspase‐dependent death of MNs in culture. We also provide data to suggest that proBDNF regulates MN PCD during development in vivo. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 699–712, 2012
Macroscale evolutionary patterns of flight muscle dimorphism in the carrion beetle Necrophila japonica
Authors: Ikeda Hiroshi , Sota Teiji 
Published: August 2011

AbstractSome insect species exhibit polymorphisms in flight muscles or wings, which provide opportunities for studying the factors that drive dispersal polymorphisms and the evolution of flightlessness in insects. We investigated the macroscale evolutionary pattern of flightlessness in the widespread Japanese beetle Necrophila japonica (Coleoptera: Silphidae), which exhibits flight muscle dimorphisms using phylogeographic approaches. N. japonica lives in both stable and unstable habitats, and the flight muscle dimorphisms may have been maintained through the use of these diverse habitats. We studied the distribution pattern of the proportion of individuals lacking flight muscles in relation to the genetic differentiation among geographic populations using an 842‐base pair sequence of the COI‐II gene. Both flight‐capable and flightless individuals occurred over the distribution area, and the flight muscle condition showed no significant phylogeographic pattern. Several populations comprised flight‐capable individuals only, whereas few comprised flightless ones only. Demographic expansion was suggested for major clades of COI‐II haplotypes, and the genetic differentiation showed an isolation‐by‐distance pattern among the populations in Japan. The proportion of flightless individuals was higher in a population with a higher annual mean temperature and with higher genetic diversity among individuals. These results indicate that geographic expansion occurred recently while flight muscle dimorphisms have been maintained, that flight‐capable individuals have colonized cooler (peripheral) habitats, and that flightlessness has increased in long‐persisting populations as suggested by high genetic diversity.
Synthesis and Thermal Stability Studies of CaFe4As3
Authors: Yi Tanghong , Dioguardi Adam P. , Klavins Peter , Curro Nicholas J. , Zhao Liang L. , Morosan E. , Kauzlarich Susan M. 
Published: August 2011

AbstractCaFe4As3 is a new intermetallic structure type that can be described as a framework comprising of FeAs4 tetrahedra. The structure has similarities to the 1‐2‐2 superconducting phase in that the Fe/As network is related to the ThCr2Si2 structure. In addition, this phase shows magnetic transitions associated with spin density waves. This phase was prepared from a Sn flux, and it has recently been reported that further expansion of this structure type via chemical substitution is limited. We have developed a solid‐state synthesis route for the preparation of CaFe4As3 that involves reacting a stoichiometric combination of the constituent elements. The thermal stability of this material was investigated over the 298–1473 K temperature range. An initial investigation of the Sn grown CaFe4As3 crystals showed that residual Sn that was present on the surface of the crystals reacted with the crystals at temperatures above 1173 K to form new phases. A thermal stability study of Sn‐free CaFe4As3 indicated that it decomposed to give CaFe2As2 and Fe2As. The thermal behavior of CaFe2As2 was also investigated and the data showed that it can also form CaFe4As3 at high temperatures. The solid‐state synthesis route presented herein and additional solid solution studies may provide opportunities for the prepartion of materials with this structure type with improved electronic properties.
α‐/β‐Formylated Boron–Dipyrrin (BODIPY) Dyes: Regioselective Syntheses and Photophysical Properties
Authors: Yu Changjiang , Jiao Lijuan , Yin Hao , Zhou Jinyuan , Pang Weidong , Wu Yangchun , Wang Zhaoyun , Yang Gaosheng , Hao Erhong 
Published: August 2011

AbstractFormylation has been performed on pyrrole‐unsubstituted dipyrromethanes 1 and boron–dipyrrin (BODIPY) dyes 4 based on a Vilsmeier–Haack reaction. It is highly regioselective and complementary and occurs exclusively at the α‐ and β‐position, respectively, for pyrrole‐unsubstituted dipyrromethanes 1 and BODIPY dyes 4. This regioselective formylation enables the syntheses of a variety of α‐ and β‐substituted BODIPY dyes. The installation of formyl groups affects the electronic properties of the BODIPY chromophore, resulting in red‐ and blueshifts of the absorption and emission maxima, respectively, for the α‐ and β‐formylatedBODIPYs 3 and 5.
Therapeutic plasma exchange and renal related vasculitis: Therapeutic apheresis academy 2010
Authors: Balogun Rasheed A. , Abdel‐Rahman Emaad M. 
Published: August 2011

AbstractTherapeutic plasma exchange (TPE), a form of extracorporeal therapy, has been used in the management of many systemic conditions some of which include the systemic vasculitides that affect the kidneys. The following is a mini review of what is known about renal related indications for TPE in such conditions and the evidence based literature available as presented at the Therapeutic Apheresis Academy in September 2010. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.
Biochemical, sensory and microbiological attributes of bream (Megalobrama amblycephala) during partial freezing and chilled storage
Authors: Song Yongling , Luo Yongkang , You Juan , Shen Huixing , Hu Sumei 
Published: August 2011

AbstractBACKGROUND: Bream is one of the main farmed freshwater fish species in China. This study aimed to examine the nucleotide degradation of bream during partial freezing and chilled storage and to assess the possible usefulness of nucleotide ratios (K, Ki, H, P, Fr and G values) as freshness indices in comparison with sensory assessment and total viable counts.RESULTS: Total viable counts were 5.74 and 4.66 log(colony‐forming units g−1) on the day of sensory rejection under chilled storage and partial freezing storage respectively. The inosine 5‐monophosphate decrease and inosine increase were faster in chilled storage than in partial freezing storage. Hypoxanthine levels increased continuously with time under both storage regimes. Among the nucleotide ratios, the K, Ki, P, G and Fr values were superior to the H value and provided useful freshness indicators for both storage conditions.CONCLUSION: Bream in chilled storage were sensorially acceptable only up to 10 days, compared with 33 days for bream in partial freezing storage. Partial freezing delayed the nucleotide degradation of bream. Copyright © 2011 Society of Chemical Industry
Studies on highly conducting Polypyrrole/Fe3O4 nanocomposites
Authors: Mathad Jyotsna Kiran , Rao R.M.V.G.K. 
Published: August 2011

AbstractPolypyrrole (PPy)/Fe3O4 nanocomposites were in situ synthesized using chemical oxidative polymerization in an aqueous solution of FeCl3.6H2O, in presence of different Fe3O4 loadings (0%–16.52%). These composites were characterized through a 4 Probe electrical conductivity measurement technique, Fourier Transform infrared spectroscopy, energy dispersive X‐ray spectroscopy, scanning electron microscopy, X‐ray diffraction, thermo gravimetric analysis, and vibrating sample magnetometer. Results showed maximum electrical conductivity of 75.28 S/cm for the 2.52% Fe3O4 loaded nanocomposite and with improved thermal stability compared with the host PPy. Furthermore, a linear relationship between saturated magnetization Ms and % composition of Fe3O4 in the above nanocomposites was observed, showing 6.34 emu/g at 16.52% Fe3O4/PPy nanocomposite. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Preparation and characterization of graphene composites with conducting polymers
Authors: Trang Le Kim Huyen , Thanh Tung Tran , Young Kim Tae , Yang Woo Seok , Kim Hyeongkeun , Suh Kwang S 
Published: August 2011

AbstractWe report a new route for preparing electro‐conductive composites based on reduced graphene oxide (RG‐O) and poly(3,4‐ethylenedioxythiophene) (PEDOT). The composites were prepared by in situ polymerization of EDOT in aqueous mixture containing RG‐O platelets modified with poly(sodium 4‐styrenesulfonate) (PSS). In the synthetic process, PSS molecules stabilize RG‐O in the aqueous phase and function as a polymerization template to hybridize PEDOT chains along RG‐O platelets. Compared with the RG‐O platelets, the resulting composites show an enhanced electrical conductivity of 9.2 S cm−1 with good thermal stability. Copyright © 2011 Society of Chemical Industry
Single fatherhood due to cancer
Authors: Yopp Justin M. , Rosenstein Donald L. 
Published: August 2011

AbstractCancer is a leading cause of widowed fatherhood in the USA. Fathers whose spouses have died from cancer constitute a potentially vulnerable population as they adjust to their role as sole or primary caregiver while managing their own grief and that of their children. The importance of addressing the psychological needs of widowed fathers is underscored by data showing that father's coping and emotional availability are closely tied to their bereaved children's mental health. Surprisingly, scant attention has been given to the phenomenon of widowed fatherhood with virtually no clinical resources or research studies devoted to fathers who have lost their wives to cancer. This commentary highlights key challenges facing this underserved population of widowers and calls for development of research agendas and clinical interventions for single fathers due to cancer. Copyright © 2011 John Wiley & Sons, Ltd.
Heterogeneous solvothermal synthesis of one‐dimensional titania nanostructures on transparent conductive glasses
Authors: Jia Qiaoying , Que Wenxiu , Zhang Jin 
Published: August 2011

AbstractThe present study reports a novel method for a direct growth of one‐dimensional (1D) TiO2 nanoarchitectures on fluorine‐doped tin oxide (FTO) conductive glass by a heterogeneous solvothermal route. Results indicate that the morphologies of the obtained samples can be controlled and changed from vertically oriented single‐crystalline rutile nanowire arrays to randomly disoriented nanotubular architectures by controlling the position of the substrate and the amount of the initial precursor. At a low concentration of the precursor, dandelion‐like TiO2 comprised of large amounts of the crystalline nanorods are found on the nonconductive surface of the horizontally oriented FTO glass, which are suitable for photocatalysis, while TiO2 nanowire arrays are grown on the conductive surface of the FTO glass, which can be used as photoanodes for sensitized solar cells to enhance the electron‐transport rate. The difference in morphology is probably related to the selective adsorption of the Cl ions, the texture of the substrate, and the immiscibility between the nonpolar solvent and the aqueous solution.
A green and fast way for reduction of graphene oxide in acidic aqueous solution via microwave assistance
Authors: Lu Ting , Pan Likun , Nie Chunyang , Zhao Zhiwei , Sun Zhuo 
Published: August 2011

AbstractA facile and pollution‐free method was applied to prepare graphene nanosheets by reducing graphene oxide in acidic aqueous solution without any toxic chemicals via microwave heating. The surface morphology, structure, and composition characterizations were carried out using atomic force microscopy, field‐emission scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy, respectively. The results showed that high‐quality and large‐area reduced graphene nanosheets were obtained.
Coherent quantum transport in ferromagnet/s±‐wave superconductor/ferromagnet structures
Authors: Zhao X. L. , Tao Y. C. 
Published: August 2011

AbstractWe extend the Blonder–Tinkham–Klapwijk approach to studying the effects of barrier strength and spin polarization on coherent spin‐polarized transport in ferromagnet (FM)/iron‐pnictide‐superconductor (SC)/FM structures with s±‐paring for the SC. It is demonstrated that the effects of barrier strength and spin polarization on the particular features of oscillations of all the reflection and transmission probabilities, and differential conductances with energy in ferromagnetic and antiferromagnetic alignments of the magnetizations of the two FMs are different, which are also different from those for the s++ model.
Effects of thermal treatment on structure and magnetic properties of nonstoichiometric perovskite‐type oxides La0.67Sr0.15□0.18MnO3‐δ
Authors: Ge J. J. , Yang M. , Xue X. B. , Du J. , Wu X. S. , Tan W. S. 
Published: August 2011

AbstractThe structural and magnetic properties of La0.67Sr0.15□0.18MnO3‐δ manganites obtained with various thermal treatment conditions have been studied. X‐ray diffraction studies show that all the samples crystallize with the rhombohedral symmetry and the space group is R‐3c. No change in structural symmetry is found for all samples with thermal treatment. However, the bond angles of MnOMn and O1MnO2 deviate from 180 and 90 °, respectively, indicating the presence of Jahn–Teller type distortion in the MnO6 octahedron. And the oxygen content shows determinant affect on compound magnetic properties. With increasing oxygen content induced by thermal treatments, the Curie temperatures TC increases systematically from ∼280 to ∼303 K, showing the dependence of sample magnetic properties on sintering processes. A maximum value of |ΔSM(T, H)| is measured to be more than 5 J/kg · K near the curie temperature, indicating the potential of utilizing the strong magnetocaloric effect of these materials in magnetic refrigeration.