bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biochemical mechanisms of methoxyfenozide resistance in the cotton leafworm Spodoptera littoralis
Authors: Mosallanejad Hadi , Smagghe Guy 
Published: April 2009

AbstractBACKGROUND: Methoxyfenozide is a lepidopteran‐specific insecticide that belongs to a new group of insecticides, the non‐steroidal ecdysteroid agonists, also called moulting accelerating compounds (MACs). To investigate the risk of resistance and possible mechanisms conferring resistance to methoxyfenozide, the authors selected in the laboratory for a resistant strain of the cotton leafworm Spodoptera littoralis (Boisd.), which is a representative lepidopteran model and an important pest in cotton and vegetables worldwide, with a high risk for resistance development.RESULTS: After selection with methoxyfenozide during 13 generations, toxicity data showed that the selected strain developed fivefold resistance to methoxyfenozide in comparison with the susceptible strain. Measurement of the detoxification enzymes demonstrated that the monooxygenase (MO) activity was 2.1 times higher in the selected strain, whereas there was no change for esterases and glutathione‐S‐transferases. When the inhibitors piperonyl butoxide (PBO), S,S,S‐tributyl phosphorotrithioate (DEF) and diethyl maleate were tested as synergists, the respective synergistic ratios were 0.97, 0.96 and 1.0 for the susceptible strain, and 2.2, 0.96 and 1.1 for the resistant strain. The significant synergistic effect by PBO concurs with the increased MO activity in the selected strain.CONCLUSION: Taken overall, the present study supports the importance of MO‐mediated metabolism in resistance to methoxyfenozide, directing tactics to fight against resistance development for this novel group of insecticides. Copyright © 2009 Society of Chemical Industry
An analysis of the persistence and potency of film‐coated seed protectant as influenced by various storage parameters
Authors: Jacob Sherry Rachel , Arunkumar MB , Gopal Madhuban , Srivastava Chitra , Sinha SN 
Published: April 2009

AbstractBACKGROUND:An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid onLycopersicon esculentum(L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages.RESULTS:High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg−1of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide.CONCLUSION:Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry
Influence of surfactants on the leaching of bentazone in a sandy loam soil
Authors: Hua Rimao , Spliid Niels H , Heinrichson Kirsten , Laursen Bente 
Published: April 2009

AbstractBACKGROUND: Surfactants are very often used for more efficient pesticide spraying, but knowledge about their influence on the leaching potential for pesticides is very limited. In the present study, the leaching of the herbicide bentazone [3‐isopropyl‐1H‐2, 1,3‐benzothiadiazin‐4(3H)‐one 2,2‐dioxide] was measured in columns with sandy loam soil with or without the addition of a non‐ionic surfactant, octylphenol ethylene oxide condensate (Triton X‐100, Triton), and an anionic surfactant, sodium dodecylbenzenesulfonate (SDBS), and in the presence of both surfactants (SDBS + Triton).RESULTS: The mobility of bentazone (B) increased in the following order: B + Triton (slowest) < B + SDBS + Triton < B < B + SDBS (fastest). When Triton X‐100 was applied to the soil together with bentazone, the leaching of bentazone in the soil decreased significantly compared with leaching of bentazone without the addition of surfactant. SDBS and Triton X‐100 neutralised their influence on the leaching speed of bentazone in the soil columns when both surfactants were applied with bentazone.CONCLUSION: From the study it can be concluded that, depending on their properties, surfactants can enhance or reduce the mobility of bentazone. By choosing a non‐ionic surfactant, bentazone mobility can be reduced, giving time for degradation and thereby reducing the risk of groundwater pollution. Copyright © 2009 Society of Chemical Industry
Effective anisotropy field in anisotropic nanostructured ferromagnetic materials
Authors: Yao Q. , Liu W. , Zhang Z. D. 
Published: April 2009

AbstractA theoretical model has been set up to investigate analytically the effective anisotropy field of the single‐phase and anisotropic nanostructured ferromagnetic materials with uniaxial magnetocrystalline anisotropy. It is revealed that the effective anisotropy field decreases with the grain alignment by the increased deviation of the magnetization from the easy‐axis in the transition region and the enhanced suppressing effect of the intergrain exchange coupling on the anisotropy. It is suggested that magnetic properties such as the soft magnetic properties could be improved by controlling the crystallographic orientation and the intergrain or interlayer exchange coupling. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Half‐metallic ferromagnetism of MnSn compound
Authors: Wang Pei‐ji , Kao Hong , Zhang Chang‐wen , Dong Jian‐min , Zhou Zhong‐xiang 
Published: April 2009

AbstractThe electronic and magnetic properties of MnSn with various crystal structures are investigated by using full‐potential linearized augmented plane‐wave method within density‐functional theory. The results show that both zinc‐blende and wurtzite structure are half‐metallic with a magnetic moment 3.0μB per formula unit, whereas the NaCl and NiAs structures are of typical metallic character. The half‐metallicity is also found to be robust with respect to the lattice compression and is maintained up to the lattice constant contraction of 8% and 9% for ZB and WZ structures, respectively. Due to the robustness of half‐metallicity with respect to the lattice change and being compatible with the semiconductors, the half‐metallic ferromagnets, when realized experimentally, would be useful in spintronic and other applications. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Design of control charts with m‐of‐m runs rules
Authors: Lim Tae‐Jin , Cho Moonsoo 
Published: April 2009

AbstractThis paper investigates economic–statistical properties of the X̄ charts supplemented with m‐of‐m runs rules. An out‐of‐control condition for the chart is either a point beyond a control limit or a run of m‐of‐m successive points beyond a warning limit. The sampling process is modeled by a Markov chain with 2m states. The steady‐state probability for each state and the average run length (ARL) from each state of the Markov chain are derived in explicit formulas. Then the stationary average run length (SALR) is derived so as to develop an economic–statistical model. Using this model, the design parameters are optimized by minimizing the cost function with constraints on the average time to signal (ATS). The X̄ chart supplemented with m‐of‐m runs rules is compared with the Shewhart X̄ chart in terms of the SARL and the cost function. Sensitivity of the design parameters with respect to the cost function is also analyzed. General guidelines for implementing the X̄ chart with m‐of‐m runs rules are presented from those observations. It should be emphasized that supplementing run rules may provide feasible and efficient solutions even if the sample size is limited, while the Shewhart X̄ chart may not. Copyright © 2009 John Wiley & Sons, Ltd.
Theoretical and applicative properties of the correlation and G‐particle‐hole matrices
Authors: Valdemoro C. , Alcoba D. R. , Tel L. M. , Pérez‐Romero E. 
Published: April 2009

AbstractWe have recently (Valdemoro et al., Sixth International Congress of the International Society for Theoretical Chemical Physics, 2008; Alcoba et al., Int J Quantum Chem, in press) reported the form of the G‐particle‐hole hypervirial equation, which can be identified with the anti‐Hermitian part of the correlation contracted Schrödinger equation (Alcoba, Phys Rev A, 2002, 65, 032519), as a tool to obtain the second‐order reduced density matrix of an N‐electron system without previous knowledge of the wave‐function. The results which have been obtained when solving the G‐particle‐hole hypervirial equation with an iterative method also described in (Valdemoro et al., Sixth International Congress of the International Society for Theoretical Chemical Physics, 2008; Alcoba et al., Int J Quantum Chem, in press) have been highly accurate. The convergence of these test calculations has been very smooth, though rather slow. One of the factors which determines the performance of the method is the accuracy with which the 3‐order correlation matrices (3‐CM) involved in the calculations are approximated. It is, therefore, necessary to optimize to the utmost the construction algorithms of these 3‐order matrices in terms of the 2‐CM. In this article, the main theoretical features of the p‐CM are described. Also, some aspects of the correlation contracted Schrödinger equation and of the G‐particle‐hole hypervirial equation are revisited. A new theorem, concerning the sufficiency of the hypervirial of the 3‐order correlation operator to guarantee a correspondence between its solution and that of the Schrödinger equation, and some preliminary results concerning the constructing algorithms of the 3‐CM in terms of the 2‐CM, are reported in the second part of this article. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
The electronically excited states of RDX (hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine): Vertical excitations
Authors: Borges Itamar , Aquino Adélia J. A. , Barbatti Mario , Lischka Hans 
Published: April 2009

AbstractThe RDX molecule, hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine, is a key component for several energetic materials, which have important practical applications as explosives. A systematic study of the electronic excited states of RDX in gas phase using time‐dependent density functional theory (TDDFT), algebraic diagrammatic construction through second order method [ADC (2)], and resolution of the identity coupled‐cluster singles and doubles method (RI‐CC2) was carried out. Transition energies and optical oscillator strengths were computed for a maximum of 40 transitions. RI‐CC2 and ADC (2) predict a spectrum shaped by three intense π‐π* transitions, two with charge transfer and one with localized character. TDDFT fails in the description of the charge transfer states. The low‐energy band of the experimental UV spectrum of RDX is assigned to the first charge transfer state. Two alternative assignments of the high‐energy band are proposed. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Inverse problems in quantum chemistry
Authors: Karwowski Jacek 
Published: April 2009

AbstractInverse problems constitute a branch of applied mathematics with well‐developed methodology and formalism. A broad family of tasks met in theoretical physics, in civil and mechanical engineering, as well as in various branches of medical and biological sciences has been formulated as specific implementations of the general theory of inverse problems. In this article, it is pointed out that a number of approaches met in quantum chemistry can (and should) be classified as inverse problems. Consequently, the methodology used in these approaches may be enriched by applying ideas and theorems developed within the general field of inverse problems. Several examples, including the RKR method for the construction of potential energy curves, determining parameter values in semiempirical methods, and finding external potentials for which the pertinent Schrödinger equation is exactly solvable, are discussed in detail. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Hydrogen and silyl bridges in group 13 and 14 atom containing molecules
Authors: Petrov Klára Tarcsay , Veszprémi Tamás 
Published: April 2009

AbstractGroup 13 and group 14 atom containing small hydrides were investigated by quantum chemical methods to characterize their possible nonclassical bridged isomers. A robust set of methods were used like NBO analysis, topological analysis of ELF, AIM theory, several bond indices (Mayer bond order, fuzzy atoms bond order, Wiberg bond index, atom–atom overlap weighted NAO bond order), and geometry. The hydrogen bridges can be interpreted by 2 electron – 3 center bonds in NBO analysis, trisynaptic X1‐Hb‐X2valence cores in ELF, and two X‐Hbbond critical points in AIM theory. The bond orders of the X‐Hbbonds are always around half of that in a classical bond, and the sum of the bond orders for the two bridging bonds is always around one. Bonding interaction between the pillar X1‐X2atoms exists in several cases, suggested by NBO analysis, ELF, the geometry and the bond orders. In the AIM picture, however, the X1‐X2pillar bond or one of the X‐Hbbridging bond is missing. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Improving reptation quantum Monte Carlo
Authors: Yuen Wai Kong , Oblinsky Daniel G. , Giacometti Robert D. , Rothstein Stuart M. 
Published: April 2009

AbstractThe reptation quantum Monte Carlo (RQMC) algorithm of Baroni and Moroni (Phys Rev Lett, 1999, 82, 4745) is a recent and promising development. In this approach, one generates a large number of reptiles: sets of electron configurations arising from consecutive drift‐diffusion moves. Within the fixed‐node approximation, one extracts estimates of the exact energy from reptiles' heads and tails (their first and last configurations of electrons, respectively), and estimates expectation values for operators that do not commute with the Hamiltonian, from their middle configurations. An advantage over conceptually equivalent algorithms is that each estimate is free from population control bias. The time‐step bias, however, may accumulate, adversely affecting one's ability to accurately estimate physical properties of atoms and molecules. For this purpose we propose an alternative algorithm, “head‐tail adjusted” reptation quantum Monte Carlo, engineered to remedy this deficiency, while still simulating the target distribution for RQMC. The effectiveness of our approach is demonstrated by an application to ground‐state LiH. We estimate the fixed‐node energy with improved reliability, without adversely affecting the quality of other, nonenergy‐related properties' estimates. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
The role of basis set superposition error in water addition reactions to Ln(III) cations
Authors: Kvamme Brandon , Wander Matthew C. F. , Clark Aurora E. 
Published: April 2009

AbstractOur goal in this work was to characterize the importance of basis set superposition error (BSSE) in the reaction energetics of water addition to highly charged metal ions that exhibit strong ion‐dipole interactions with water. The gas phase water addition reactions, M(H2O) + H2O → M(H2O) [M = La(III), Lu(III); N = 0–8] have been studied, with a particular emphasis on a posteriori methods for calculating BSSE and its constituent energetic components as a function of M(H2O) cluster size and water basis set. Because of accumulation of BSSE within the subclusters in the reaction series, the successive reaction counterpoise method for determining the BSSE correction interaction energies is advocated. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Mechanism of hydrogen activation by frustrated Lewis pairs: A molecular orbital approach
Authors: Hamza Andrea , Stirling András , András Rokob Tibor , Pápai Imre 
Published: April 2009

AbstractA detailed molecular orbital treatment of the heterolytic hydrogen splitting by bulky Lewis acid‐base pairs is presented. The frontier molecular orbitals of the proposed reactive intermediate are shown to be preorganized but otherwise practically identical to those of the free acid and base molecules. The concerted interaction of the Lewis centers with hydrogen leading to the polarization and, ultimately, to the cleavage of the HH bond is examined, and the bridge role of hydrogen molecule in the electron transfer is pointed out. The formation of the new covalent bonds is monitored by bond order and natural localized molecular orbital calculations, and found to be synchronous. The stability of the product is interpreted on the basis of favorable orbital interactions. A comparison of various hydrogen activation mechanisms emphasizes the common donation/back‐donation motifs and the different ways of making them feasible. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Interaction of monovalent cations with acetonitrile
Authors: Černušák Ivan , Aranyosiová Monika , Vollárová Ol'Ga , Velič Dušan , Kirdajová Ol'Ga , Benko Ján 
Published: April 2009

AbstractSolvation of monovalent cations (Me+) of alkali metalsNa+, K+, Rb+, and Cs+, coinage metalsCu+, Ag+, Au+, and p‐block elements Ga+, In+, and Tl+ with acetonitrile was studied by means of ab initio calculations and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The intermolecular interactions in the complexes Me+···CH3CN were investigated using the coupled clusters theory including single, double, and noniterative triple substitutions (CCSD(T)) in conjunction with the Pol and Pol‐dk basis sets. The binding energies of these donor‐acceptor complexes were estimated; taking into account the basis set superposition error, zero‐point vibrations, correlation contribution, and scalar relativistic corrections. The theoretical ΔG0298 K values based on CCSD(T)/Pol and/or CCSD(T)/Pol‐dk binding energies correlated well with experimental transfer Gibbs energies (from water to acetonitrile) for the series of cations. In the case of Au monocation, relativistic correction turned out to be extremely important. Composition of the complex of Ag+ and Na+ with acetonitrile was determined by using SIMS supporting both theoretical and experimental transfer Gibbs energies. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Collision detection and untangling for surgical robotic manipulators
Authors: Morvan Tangui , Martinsen Magnar , Reimers Martin , Samset Eigil , Elle Ole Jakob 
Published: April 2009

AbstractBackgroundRobotic‐assisted minimally invasive surgery provides several advantages over traditional surgery; however, it also has several drawbacks, such as possible collisions between the robotic arms and a limited field of view.MethodsA generic method for tracking the configuration of a surgical manipulator in real time is presented. It is coupled with a collision detection and dynamic simulation algorithm, allowing the operator to detect collisions between robotic arms before they happen and presenting the best possible untangling direction to get out of collisions.ResultsOur algorithm successfully tracks the configuration of the Zeus® surgical system and accurately detects possible collisions in real time. A pilot study on our system proved its efficiency in reducing the duration and severity of collisions, at the price of longer completion times.ConclusionOur system helps alleviate the collision problem by reducing the time in collision. Copyright © 2009 John Wiley & Sons, Ltd.
A laboratory training and evaluation technique for computer‐aided oral implant surgery
Authors: Widmann Gerlig , Stoffner Rudolf , Keiler Martin , Zangerl Antoinette , Widmann Roland , Puelacher Wolfgang , Bale Reto 
Published: April 2009

AbstractBackgroundNavigated oral implant surgery requires knowledge and skills in computed tomography (CT) imaging, three‐dimensional (3D) planning, and use of surgical navigation systems. To improve teaching and training, a laboratory training and evaluation technique has been developed.MethodsThe technique uses a surgical navigation system, a dental dummy and anonymous data of previously treated patients, including duplicated dental stone casts, individualized registration mouthpieces and CT scans. Training consists of definition of the prosthetic goal, 3D planning and navigated model surgery. For evaluation, a post‐surgical CT of the drilled dental stone casts is fused with the original planning CT.ResultsEach step of navigated implant surgery can be simulated and trained. Post‐surgical evaluation includes Euclidean distance, normal distance, angular deviations and damage to critical anatomical structures, such as nerves and sinuses.ConclusionsThe presented technique allows for successful laboratory training and evaluation of computer‐aided oral implant surgery. Copyright © 2009 John Wiley & Sons, Ltd.
Human cytomegalovirus targets different subsets of antigen‐presenting cells with pathological consequences for host immunity: implications for immunosuppression, chronic inflammation and autoimmunity
Authors: Varani Stefania , Frascaroli Giada , Landini Maria Paola , Söderberg‐Nauclér Cecilia 
Published: April 2009

AbstractHuman cytomegalovirus (HCMV) infection is a major cause of morbidity and mortality in patients with an impaired immune system. The virus itself can cause transitory but significant immunosuppression in immunocompetent as well as immunocompromised infected individuals. Besides immunosuppression, HCMV‐infected patients often develop other signs of immune dysfunction, such as autoimmune phenomena. Signs of active viral infection have also been identified in inflammatory lesions in a number of autoimmune diseases, highlighting the potential role of HCMV in the genesis or maintenance of such immunopathological phenomena. HCMV targets several cells of the immune system and subverts host immune functions to its own advantage. We present here an overview of the effects of HCMV infection on antigen‐presenting cells and relate in vitro data to immunopathological findings in HCMV‐infected patients. Possible mechanisms by which HCMV can induce host immunopathology will also be discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Adenovirus receptors: implications for tropism, treatment and targeting
Authors: Arnberg Niklas 
Published: April 2009

AbstractAdenoviruses (Ads) are the most frequently used viral vectors in gene therapy and cancer therapy. Obstacles to successful clinical application include accumulation of vector and transduction in liver cells, coupled with poor transduction of target cells and tissues such as tumours. Many host molecules, including coagulation factor X, have been identified and suggested to serve as mediators of Ad liver tropism. This review summarises current knowledge concerning these molecules and the mechanisms used by Ads to bind to target cells, and considers the prospects of designing vectors that have been detargeted from the liver and retargeted to cells and tissues of interest in the context of gene therapy and cancer therapy. Copyright © 2009 John Wiley & Sons, Ltd.