bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of nitrile functionalized graphene on the properties of poly(arylene ether nitrile) nanocomposites
Authors: Yang Xulin , Zhan Yingqing , Yang Jian , Tang Hailong , Meng Fanbing , Zhong Jiachun , Zhao Rui , Liu Xiaobo 
Published: February 2012

AbstractIn this study, novel nitrile functionalized graphene (GN‐nitrile)/poly(arylene ether nitrile) (PEN) nanocomposites were prepared by an easy solution‐casting method and investigated for the effect of surface modification on the dielectric, mechanical and thermal properties. Graphene (GN) was first functionalized by introduction of nitrile groups onto the GN plane, which was confirmed by scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, thermogravimetric analysis and dispersibility research. Compared with pure GN, the grafted nitrile groups on the GN‐nitrile can interact with nitrile groups in PEN and lead to flat but better dispersion and stronger adhesion in/to the PEN matrix. Consequently, GN‐nitrile had a more significant enhancement effect on the properties of PEN. The dielectric constant of the PEN/GN‐nitrile nanocomposite with 5 wt% GN‐nitrile reaches 11.5 at 100 Hz, which is much larger than that of the pure PEN matrix (3.1). Meanwhile, dielectric loss is quite small and stable and the dielectric properties showed little frequency dependence. For 5 wt% GN‐nitrile reinforced PEN composites, increases of 17.6% in tensile strength, 26.4% in tensile modulus and 21 °C in Td5% were obtained. All PEN/GN‐nitrile nanocomposite films can stand high temperature, up to 480 °C. Hence, novel dielectric PEN/GN‐nitrile nanocomposite films with excellent mechanical and thermal properties can be used as dielectric materials under some critical circumstances such as high wear and temperature. Copyright © 2012 Society of Chemical Industry
All the fundamental massless fields in bosonic string theory
Authors: Manoukian E.B. 
Published: February 2012

AbstractA systematic analysis of the massless fields in the mass spectra of bosonic strings is carried in arbitrary spacetime dimension D > 2. The emphasis is put on the derivations of their propagators, their polarization aspects and the underlying constraints involved. The treatment is given, in the presence of external sources, in the celebrated Coulomb gauge for the second rank tensors and vector fields, which ensures positivity – a result which is also established in the process. No constraints are imposed on the external sources so that their components may be varied independently generating complete expressions for the propagators. This latter condition is an important one in the generation of dynamical theories with constraints involving such modifications as Faddeev‐Popov factors.
Non‐perturbative gauge couplings from holography
Authors: Billò M. , Frau M. , Giacone L. , Lerda A. 
Published: February 2012

AbstractWe show how D‐instanton corrections modify the dilaton‐axion profile emitted by an O7/D7 system turning it into the non‐singular F‐theory background which corresponds to the effective coupling on a D3 probe.
Asymptotically Lifshitz black holes in Einstein‐Maxwell‐dilaton theories
Authors: Tarrio J. 
Published: February 2012

AbstractWe study Einstein‐Maxwell‐dilaton theories with a cosmological constant and U(1)N gauge symmetry, considering metrics asymptotically approaching the Lifshiftz metric. We study the dependence of the phase diagram on the value of the dynamical exponent. Along the way, we apply holographic renormalization and propose a counterterm valid for arbitrary dimension and dynamical exponent in our setup.
Dimethyl disulfide is an induced systemic resistance elicitor produced by Bacillus cereus C1L
Authors: Huang Chien‐Jui , Tsay Jia‐Fang , Chang Shu‐Yu , Yang Hsiu‐Ping , Wu Wen‐Shi , Chen Chao‐Ying 
Published: February 2012

AbstractBACKGROUND: Bacillus cereus C1L is a plant growth‐promoting rhizobacterium and can elicit induced systemic resistance (ISR) in plants against necrotrophic pathogens. However, little is known about ISR elicitors produced by B. cereus C1L, and no ISR elicitor has been identified and characterised. Therefore, the objective of this study is to identify volatile ISR elicitor(s) produced by B. cereus C1L.RESULTS: The volatile metabolites produced by B. cereus C1L were extracted, separated and identified by solid‐phase microextraction, gas chromatography and mass spectrometry. Dimethyl disulfide (DMDS) was the only separated metabolite being determined. Afterwards, application of DMDS by means of soil drench significantly protected tobacco and corn plants against Botrytis cinerea and Cochliobolus heterostrophus, respectively, under greenhouse conditions. The results reveal that DMDS could play an important role in ISR by B. cereus C1L.CONCLUSION: This is the first report of DMDS as an elicitor produced by an ISR‐eliciting B. cereus strain and its ability to suppress plant fungal diseases under greenhouse conditions. It is suggested that DMDS has potential for practical use in controlling plant foliar diseases besides soil fumigation. Copyright © 2012 Society of Chemical Industry
Effects of non‐repellent termiticides on the tunneling and walking ability of the eastern subterranean termite (Isoptera: Rhinotermitidae)
Authors: Quarcoo Franklin Y , Hu Xing Ping , Appel Arthur G 
Published: February 2012

AbstractBACKGROUND: Non‐repellent insecticides, including fipronil and indoxacarb, are becoming increasingly important for soil treatments to manage the eastern subterranean termite, Reticulitermes flavipes (Kollar). The effects of these insecticides on termite walking and tunneling behavior could significantly reduce their efficacy against colonies.RESULTS: Groups of R. flavipes were exposed to several concentrations of commercial formulations of fipronil and indoxacarb, and the ability of treated termites to tunnel in soil and walk was assessed. Increasing insecticide concentration resulted in a reduction in the ability of R. flavipes to walk, tunnel and form tunnel branches; the importance of these effects on the use of non‐repellent insecticides is discussed.CONCLUSION: Exposure of R. flavipes to 1, 10 or 50 mg L−1 of fipronil or 50, 100 or 200 mg L−1 of indoxacarb significantly reduced termite walking and tunneling and the number of tunnel branches. Distance walked (ca 73 mm) by untreated control termites did not change over time for at least 16 h after treatment; control termites formed ca 150 cm of tunnels with ca 40 branches. Copyright © 2012 Society of Chemical Industry
Evaluation of dazomet as fumigant for the control of brown root rot disease
Authors: Fu Chuen‐Hsu , Hu Bau‐Yuan , Chang Tun‐Tschu , Hsueh Kai‐Leen , Hsu Wei‐Tse 
Published: February 2012

AbstractBACKGROUND: Brown root rot disease caused by Phellinus noxius is widespread in approximately 216 tree and plant species in tropical and subtropical countries. No direct means of protection against P. noxius infection have thus far been developed. Therefore, in this field survey, a method was developed for preventing and controlling brown root rot disease using fumigation with dazomet.RESULTS: Tracers were used to monitor the effect of dazomet fumigation. The results from field surveys and phytotoxicity tests showed that dazomet is able to kill P. noxius without any side effects on plants.CONCLUSION: The use of an environmentally friendly agent to control brown root rot disease is needed, and prevention of the disease is more important than treatment. Hence, chemical fumigation with 60 g m−2 of 98% dazomet may be a possible means of preventing P. noxius incursion in agriculture, gardening and agroforestry. Copyright © 2012 Society of Chemical Industry
Entropy‐change measurement of electrocaloric effect of BaTiO3 single crystal
Authors: Bai Yang , Ding Kai , Zheng Guang‐Ping , Shi San‐Qiang , Qiao Lijie 
Published: February 2012

AbstractWe demonstrated a characterization method of entropy‐change measurement for the study of the electrocaloric effect (ECE). After the specific heat capacity was measured under different applied fields using a differential scanning calorimeter (DSC) accompanied with DC power supply, the electrocaloric ΔS was calculated from the temperature integral of specific heat capacities based on the basic definition of entropy. The ΔS–T curve of BaTiO3 single crystal showed a sharp peak around Tc, which increased gradually and shifted to higher temperature with the rise of applied field. A high ECE with ΔS = 1.9 J/kg K and ΔT = 1.6 K is achieved under a quite low field of 10 kV/cm. The results agreed with the thermodynamic calculation. It provides a direct, precise, and time‐efficient method for the electrocaloric studies.
Design and maskless fabrication of ultrathin suspended membranes of GaN
Authors: Tiginyanu I. M. , Popa V. , Stevens‐Kalceff M. A. , Gerthsen D. , Brenner P. , Pavlidis D. 
Published: February 2012

AbstractWe report the maskless fabrication of ultrathin suspended GaN membranes designed by focused ion beam treatment of the GaN epilayer surface with subsequent photoelectrochemical etching. This technological approach allows the fabrication of ultrathin membranes, as well as supporting micro/nanocolumns in a controlled fashion. The analysis of the spatial and spectral distribution of microcathodoluminescence demonstrates that the membranes exhibit mainly yellow luminescence. These results pave the way for the fabrication of ultrathin suspended GaN membranes for MEMS/NEMS applications.magnified image(© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Time‐dependent schrödinger equation with Markovian outgoing wave boundary conditions: Applications to quantum tunneling dynamics and photoionization
Authors: Chou Chia‐Chun , Wyatt Robert E. 
Published: February 2012

AbstractMarkovian outgoing wave boundary conditions are introduced as an approximate method to reduce the size of the computational grid for time integration of the time‐dependent Schrödinger equation. The ratio and polynomial methods developed as open boundary conditions are applied to the wave function at the boundaries of the computational grid. This computational method is used to study the wave packet dynamics for a metastable well, a double well, and strong‐field ionization of a model atom. Accurate results demonstrate that this method can significantly reduce the number of grid points required in a dynamical calculation for quantum dynamical problems. © 2012 Wiley Periodicals, Inc.
Reactivity of amines with hypochlorous acid: Computational study of steric, electronic, and medium effects
Authors: Tarade Tena , Vrček Valerije 
Published: February 2012

AbstractN‐Chlorination reactions of alkyl‐, cycloalkyl‐, heterocyclic, and aromatic amines by HOCl have been investigated in the gas and aqueous phase. Density functional (B3LYP), double hybrid (B2PLYPD), and composite theoretical model (G3B3) have been used to assess steric, electronic, and solvent effects on the reactivity of different families of amines toward HOCl. When solvent effects are included by using CPCM/UAHF model, all computational methods predict the same order of reactivity within each group of amines. In agreement with experimental data, heterocyclic amines have the highest reactivity, with energy barriers calculated between 160 and 225 kJ mol−1 (B2PLYPD/AUG‐cc‐pVTZ//B3LYP/6‐31G(d) level). The substituted anilines are the least reactive species, with energy barriers calculated as high as 300 kJ mol−1. Two different reaction mechanisms of N‐chlorination have been considered in the gas phase: the one which includes the transition state TSa with cyclic arrangement of four atoms (N, Cl, O, and H) involved in an intramolecular rearrangement, and the second in which the hydrogen‐bridged structure TSb is characterized with the linear NClO moiety. The former is energetically more feasible (ca. 120 kJ mol−1) for alkyl‐, cycloalkyl‐, and heterocyclic amines, whereas the latter is operative in the case of aromatic amines. If two water molecules are explicitly included in the calculations, the rate‐determining transition state TSw has been located for N‐chlorination of all amines under study. It is characterized by eight‐membered ring geometry in which water molecules assist the simultaneous transfer of the three hydrogen atoms coupled with the NCl bond formation. To reproduce the experimentally observed trends in reactivity of amines, the inclusion of bulk and specific solvent effects is mandatory. Steric effects have been found to govern the reactivity of alkylamines, that is, more bulkier amines react slower with HOCl. It has been found that electronic structure parameters (HOMO–LUMO gap, natural bond orbital occupancy, and NPA charge on N atom) can be successfully used as descriptors for the reactivity of heterocyclic and aromatic amines. These results indicate the predictive power of our computational approach, which can be applied to calculate nucleophilic reactivities of more complex structures of environmentally or biologically relevant amines. © 2012 Wiley Periodicals, Inc.
Theoretical studies on structural and spectroscopic properties of photoelectrochemical cell ruthenium sensitizers, derivatives of AR20
Authors: Chen Jie , Wang Jian , Bai Fu‐Quan , Pan Qing‐Jiang , Zhang Hong‐Xing 
Published: February 2012

AbstractSpecial efforts were devoted to improve the absorption behavior of AR20 in visible region. Density functional theory (DFT)‐based approaches were applied to explore the electronic structure properties of AR20 and its derivatives. Time‐dependent DFT results indicate that the ancillary ligand controls the molecular orbital (MO) energy levels and masters the absorption transition nature. The deprotonation of anchoring ligand not only affects the frontier MO energy levels but also determines the energy gaps of highest occupied MO–lowest unoccupied MO (LUMO) and LUMO–LUMO+1. Introducing thiophene groups into ancillary ligands would enhance the efficiency of the final dye‐sensitized solar cell (DSSC). The absorption intensity of the thiophene substituted derivatives of AR20 is irrelevant with environment circumstance change, such as pH value. This special nature prognosticates the thiophene‐substituted derivatives of AR20 which would have a broad application in DSSC. © 2012 Wiley Periodicals, Inc.
Combination of approximate spin‐projection and spin‐restricted calculations based on ONIOM method for geometry optimization of large biradical systems
Authors: Kitagawa Y. , Yasuda N. , Hatake H. , Saito T. , Kataoka Y. , Matsui T. , Kawakami T. , Yamanaka S. , Okumura M. , Yamaguch K. 
Published: February 2012

AbstractIn this article, we combine the approximate spin projection (AP) and the spin‐restricted (R) calculations based on ONIOM method for a geometry optimization of large biradical systems such as polynuclear metal complexes. This two‐layer quantum mechanics/quantum mechanics′ (QM/QM′) (AP/R) method treats atoms of an inner layer around the spin sources with the AP method, whereas the whole atoms including the peripheral ligands are calculated by the R method. The AP/R method is applied for the geometry optimizations of chromium(II) ions in Cr2(O2CCH3)4(OH2)2 (1) and Cr2{O2CPh(CHMe2)3}4 (2) complexes that involve quadruple CrCr bonds. The optimized structural parameters indicate that the error of the two‐layer combination is smaller than 0.01 Å in the optimized CrCr bond length on both complexes. The error is only 12.3% of the spin contamination error and 1.7% of the static correlation correction in the complex 1. The error of the two‐layer combination in a total energy is also estimated to be lower than 1 kcal mol−1 in both complexes. © 2012 Wiley Periodicals, Inc.
On induced Folkman numbers
Authors: Dudek Andrzej , Ramadurai Reshma , Rödl Vojtěch 
Published: February 2012

AbstractIn 1970, Folkman proved that for any graph G there exists a graph H with the same clique number as G. In addition, any r ‐coloring of the vertices of H yields a monochromatic copy of G. For a given graph G and a number of colors r let f(G, r) be the order of the smallest graph H with the above properties. In this paper, we give a relatively small upper bound on f(G, r) as a function of the order of G and its clique number. © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 40, 493–500, 2012
Direct and Transmission Milling of Suspended Silicon Nitride Membranes With a Focused Helium Ion Beam
Authors: Marshall Michael M. , Yang Jijin , Hall Adam R. 
Published: February 2012

SummaryHelium ion milling of suspended silicon nitride thin films is explored. Milled squares patterned by scanning helium ion microscope are subsequently investigated by atomic force microscopy and the relation between ion dose and milling depth is measured for both the direct (side of ion incidence) and transmission (side opposite to ion incidence) regimes. We find that direct‐milling depth varies linearly with beam dose while transmission‐milling depth varies with the square of the beam dose, resulting in a straightforward method of controlling local film thickness. SCANNING 34: 101‐106, 2012. © 2012 Wiley Periodicals, Inc.
Use of Multiphoton Microscopy to Diagnose Liver Cancer and Lung Metastasis in an Orthotopic Rat Model
Authors: Yan Jun , Zhuo Shuangmu , Chen Gang , Tan Changjun , Zhu Weifeng , Lu Jianping , Fan Jia , Chen Jianxin , Zhou Jian 
Published: February 2012

SummaryLiver or lung biopsy for suspicious lesions has several disadvantages such as bleeding, bile leak or pneumothorax, needle track seeding, and time‐consuming histopathological procedure. The ability to directly observe cellular and subcellular details and then perform “optical biopsy” is a major goal in the development of new interventional techniques. Multiphoton microscopy (MPM) enables real‐time noninvasive visualization of tissue architecture and cell morphology in live tissue. We performed a study to evaluate whether MPMcan make real‐time optical diagnosis for liver cancer and lung metastasis using an orthotopic rat model with Morris hepatoma. We found that real‐time high‐resolution MPMimaging could clearly show tissue architecture and cell morphology. In the normal liver tissue, MPMimaging clearly revealed the blood‐filled sinusoids and cords of hepatocytes. In the cancerous tissue, MPMimaging clearly illustrated that cancer cells displayed marked cellular and nuclear pleomorphism. MPMimages were comparable to golden standard hematoxylin‐eosin staining images. Moreover, MPMimaging had deep penetration with the capability of optical sectioning. In short, MPMcan make real‐time optical diagnosis for liver cancer and lung metastasis. This study provides the groundwork for further using multiphoton endoscopy to perform real‐time noninvasive “optical biopsy” for liver cancer and lung metastasis in the near future. SCANNING 34: 271‐277, 2012. © 2012 Wiley Periodicals, Inc.
Second‐order competences and Schumpeterian rents
Authors: Danneels Erwin 
Published: February 2012

AbstractSecond‐order competences, a type of dynamic capability, enable firms to engage in a process of Schumpeterian competition. This study examines the effects of marketing and R&D second‐order competences (the abilities to create new market‐related and technological resources) on firm profitability. Based on multiple informant surveys and archival data from U.S. public manufacturing firms, competitive turbulence is found to present contrasting contingencies for the effects of these competences on return on assets (ROA). The effect of marketing competence on ROA was positive under stable and moderate competitive conditions, whereas the effect of R&D competence on ROA was positive under volatile competitive conditions. Copyright © 2012 Strategic Management Society.
Magnetic‐Nanoparticle‐Doped Carbogenic Nanocomposite: An Effective Magnetic Resonance/Fluorescence Multimodal Imaging Probe
Authors: Srivastava Sachchidanand , Awasthi Rishi , Tripathi Deepak , Rai Mohit K. , Agarwal Vikas , Agrawal Vinita , Gajbhiye Namdeo S. , Gupta Rakesh K. 
Published: February 2012

AbstractA novel and facile approach is developed to synthesize a magnetic nanoparticle (iron oxide)‐doped carbogenic nanocomposite (IO‐CNC) for magnetic resonance (MR)/fluorescence imaging applications. IO‐CNC is synthesized by thermal decomposition of organic precursors in the presence of Fe3O4 nanoparticles with an average size of 6 nm. IO‐CNC shows wavelength‐tunable fluorescence properties with high quantum yield. Magnetic studies confirm the superparamagnetic nature of IO‐CNC at room temperature. IO‐CNC shows MR contrast behavior by affecting the proton relaxation phenomena. The measured longitudinal (r1) and transverse (r2) relaxivity values are 4.52 and 34.75 mM−1 s−1, respectively. No apparent cytotoxicity is observed and the nanocomposite shows a biocompatible nature. In vivo MR studies show both T1 and T2* contrast behavior of the nanocomposite. Fluorescence imaging indicates selective uptake of IO‐CNC by macrophages in spleen.
Tumor-Initiating Label-Retaining Cancer Cells in Human Gastrointestinal Cancers Undergo Asymmetric Cell Division
Authors: Xin Hong-Wu , Hari Danielle M. , Mullinax John E. , Ambe Chenwi M. , Koizumi Tomotake , Ray Satyajit , Anderson Andrew J. , Wiegand Gordon W. , Garfield Susan H. , Thorgeirsson Snorri S. , Avital Itzhak 
Published: February 2012

Abstract
Label-retaining cells (LRCs) have been proposed to represent adult tissue stem cells. LRCs are hypothesized to result from either slow cycling or asymmetric cell division (ACD). However, the stem cell nature and whether LRC undergo ACD remain controversial. Here, we demonstrate label-retaining cancer cells (LRCCs) in several gastrointestinal (GI) cancers including fresh surgical specimens. Using a novel method for isolation of live LRCC, we demonstrate that a subpopulation of LRCC is actively dividing and exhibits stem cells and pluripotency gene expression profiles. Using real-time confocal microscopic cinematography, we show live LRCC undergoing asymmetric nonrandom chromosomal cosegregation LRC division. Importantly, LRCCs have greater tumor-initiating capacity than non-LRCCs. Based on our data and that cancers develop in tissues that harbor normal-LRC, we propose that LRCC might represent a novel population of GI stem-like cancer cells. LRCC may provide novel mechanistic insights into the biology of cancer and regenerative medicine and present novel targets for cancer treatment.
Disclosure of potential conflicts of interest is found at the end of this article.
Problem management process, filling the gap in the systems engineering processes between the risk and opportunity processes
Authors: Olson Bill A. , Mazzuchi Thomas A. , Sarkani Shahram , Forsberg Kevin 
Published: February 2012

AbstractProblem Management is not recognized as a Systems Engineering process. Unlike risk management, where risks could impact a project at some future date, problems impact the project now. Therefore, a robust Problem Management process should be established (similar to the risk management process described in Chapter 5 of the INCOSE handbook [Hamelin, Walden, and Krueger, INCOSE systems engineering handbook v3.2: Improving the process for SE practitioners, INCOSE, Seattle, WA, 2010]) early in a projects formulation. The process should be continuous throughout all phases of the project life cycle and should be included as a part of the project System Engineering Management Plan. The process should, at a minimum, address: problem identification, problem assessment, problem root cause investigation, problem corrective action planning, reporting, a roll‐up of all current problems, problem closure, and a strong interface with the project's knowledge management system. This paper proposes a Problem Management process based on the foundations of risk and opportunity management which could be used by corporations, government agencies, and programs to establish a robust problem management process for use on their projects. © 2012 Wiley Periodicals, Inc. Syst Eng