bluuebunny/crossref_metadata_2025_split huggingface dataset:
H∞ Guaranteed Cost Control for LPV Systems Subject to The Gain Constraint
Authors: Zhao Yangyang , Yang Jianying , Lei Zhengdong 
Published: March 2013

AbstractThis paper deals with the problem of H∞ guaranteed cost control for linear parameter varying (LPV) systems subject to the gain constraint. Specifically, our main goal is to design a controller such that the closed‐loop system is exponentially stable with the H∞ performance index, the quadratic performance index, and the gain within the desired constraints over the entire parameter region. In order to achieve this goal, less conservative and more practical sufficient conditions for the existence of the state feedback controller are proposed by introducing the parameter dependent Lyapunov function and many extra freedom degrees in terms of linear matrix inequalities and a free parameter matrix. The parameter matrix aspecially can regulate the gain freely without the influence of the desired performance to meet the additional design criteria enhancing the practicability and the design flexibility. As a special case, relevant results are extended to design a static output feedback controller. One numerical example is used to show advantages of the proposed approach.
Consensus of Fractional‐Order Uncertain Multi‐Agent Systems Based on Output Feedback
Authors: Yin Xiuxia , Hu Songlin 
Published: March 2013

AbstractThis paper is devoted to the consensus protocol design for a set of agents with fractional‐order uncertainty dynamics where the fractional order α satisfies 0 < α < 2. For multi‐agent systems (MASs) with fixed undirected topology, a distributed static output feedback protocol is proposed with an undetermined system matrix. Based on model transformation and fractional‐order stability theory, sufficient conditions are derived to ensure the consensus of MASs in terms of linear matrix inequalities (LMIs). Finally, a simulation example is employed to validate the effectiveness of the proposed consensus protocol.
Robust Finite‐Time Stability and Stabilization of Linear Uncertain Time‐Delay Systems
Authors: Stojanovic Sreten B. , Debeljkovic Dragutin Lj. , Antic Dragan S. 
Published: March 2013

AbstractRobust finite‐time stability and stabilization problems for a class of linear uncertain time‐delay systems are studied. The concept of finite‐time stability is extended to linear uncertain time‐delay systems. Based on the Lyapunov method and properties of matrix inequalities, a sufficient condition that ensures finite‐time stability of linear uncertain time‐delay systems is given. By virtue of the results on finite‐time stability, a memoryless state feedback controller that guarantees that the closed‐loop system is finite time stable, is proposed. The controller design problem is solved by using the linear matrix inequalities and the cone complementarity linearization iterative algorithm. Numerical examples verify the efficiency of the proposed methods.
Interaction studies of muts and mutl with DNA containing the major cisplatin lesion and its mismatched counterpart under equilibrium and nonequilibrium conditions
Authors: Sedletska Yuliya , Culard Françoise , Midoux Patrick , Malinge Jean‐Marc 
Published: March 2013

ABSTRACTThe DNA mismatch repair (MMR) system participates in cis‐diamminedichloroplatinum (II) (cisplatin) cytotoxicity through signaling of cisplatin DNA lesions by yet unknown molecular mechanisms. It is thus of great interest to determine whether specialized function of MMR proteins could be associated with cisplatin DNA damage. The major cisplatin 1,2‐d(GpG) intrastrand crosslink and compound lesions arising from misincorporation of a mispaired base opposite either platinated guanine of the 1,2‐d(GpG) adduct are thought to be critical lesions for MMR signaling. Previously, we have shown that cisplatin compound lesion with a mispaired thymine opposite the 3′ platinated guanine triggers new Escherichia coli MutS ATP‐dependent biochemical activities distinguishable from those encountered with DNA mismatch consistent with a role of this lesion in MMR‐dependent signaling mechanism. In this report, we show that the major cisplatin 1,2‐d(GpG) intrastrand crosslink does not confer novel MutS postrecognition biochemical activity as studied by surface plasmon resonance spectroscopy. A fast rate of MutS ATP‐dependent dissociation prevents MutL recruitment to the major cisplatin lesion in contrast to cisplatin compound lesion which authorized MutS‐dependent recruitment of MutL with a dynamic of ternary complex formation distinguishable from that encountered with DNA mismatch substrate. We conclude that the mode of cisplatin DNA damage recognition by MutS and the nature of MMR post‐recognition events are lesion‐dependent and suggest that MMR signaling through the major cisplatin lesion is unlikely to occur. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 636–647, 2013.
Characterization of the melanoma brain metastatic niche in mice and humans
Authors: Amit Moran , Laider‐Trejo Leonor , Shalom Vardit , Shabtay‐Orbach Ayelet , Krelin Yakov , Gil Ziv 
Published: March 2013

AbstractBrain metastases occur in 15% of patients with melanoma and are associated with a dismal prognosis. Here, we investigate the architectural phenotype and stromal reaction of melanoma brain metastasis in mice and humans. A syngeneic, green fluorescence protein (GFP)‐expressing murine B16‐F1 melanoma clone was introduced via intracardiac injection, and was examined in vivo in comparison with human specimens. Immunofluorescence analyses of the brain metastases revealed that F4/80+ macrophages/microglia were most abundant at the tumor front, but rare in its core, where they were found only around blood vessels (P = 0.01). Similar pattern of infiltration was found in CD3+ T cells (P < 0.01). Infiltrating T cells were prominently CD4+ compared with CD8+ T cells (P < 0.001). Blood vessels (CD31+) were less abundant at the tumor front than in its center (12 ± 1 vs. 4 ± 0.6 vessels per high‐power field [HPF], P < 0.001). In contrast, there were few vessels at the tumor front, but their diameter was significantly larger at the front (8236 μm2 vs. 4617 μm2 average cross‐sectional area, P < 0.005). This is the first comparative analysis of melanoma brain metastases showing similar stromal reaction in murine models and human specimens. Our results validate the utility of this murine model of melanoma brain metastases for investigating the mechanism of the human disease.
Knowledge Extraction from Catalysis of the Past: A Case of Selective CO Oxidation over Noble Metal Catalysts between 2000 and 2012
Authors: Günay M. Erdem , Yildirim Ramazan 
Published: March 2013

AbstractThe objective of this work is to demonstrate that some valuable knowledge can be extracted from past publications by using various data mining tools so that the continuously growing experience accumulated in the literature over the years can be used in a more effective manner. Selective CO oxidation over noble metal catalysts is chosen as a case to test the validity of this approach because a considerable number of papers were published on this subject in the last decade. Thus, 249 papers published in the last 12 years have been inspected, 80 of which were used to form a database containing 5610 data points. First, the database was analyzed by using decision tree classification to determine the conditions that lead to high CO conversion. Then, the relative importance of various catalyst preparation and operational variables for CO conversion were determined by using artificial neural networks. Finally, the database was separated into smaller clusters by using a genetic algorithm‐based clustering technique, and the data in each cluster was modeled by artificial neural networks to predict the effects of individual catalyst preparation and operational conditions on the catalytic activity. All these analyses were effective in the extraction of knowledge from the literature and the deduction of some useful trends, rules, and correlations, which are otherwise not easily comprehensible.
Sol–Gel Coordination Chemistry: Building Catalysts from the Bottom‐Up
Authors: Serrano Elena , Linares Noemi , Garcia‐Martinez Javier , Berenguer Jesús. R. 
Published: March 2013

AbstractThe development of synthetic routes for the tailoring of efficient silica‐based heterogeneous catalysts functionalized with coordination complexes or metallic nanoparticles has become a important goal in chemistry. Most of these techniques have been based on postsynthetic treatments of preformed silicas. Nevertheless, there is an emerging approach, so‐called sol–gel coordination chemistry, based on co‐condensation during the sol–gel preparation of the hybrid material of the corresponding complex or nanoparticle modified with terminal trialkoxysilane groups with a silica source (such as tetraethoxysilane) and in the presence of an adequate surfactant. This method leads to the production of new mesoporous metal complex‐silica materials, with the metallic functionality incorporated homogeneously into the structure of the hybrid material, improving the stability of the coordination complex (which is protected by the silica network) and reducing the leaching of the active phase. This technique also offers the actual possibility of functionalizing silica or other metal oxides for a wider range of applications, such as photonics, sensing, and biochemical functions.
Copper Versus Thioether‐Centered Oxidation: Mechanistic Insights into the Non‐Innocent Redox Behavior of Tripodal Benzimidazolylaminothioether Ligands
Authors: Martínez‐Alanis Paulina R. , Sánchez Eguía Brenda N. , Ugalde‐Saldívar Víctor M. , Regla Ignacio , Demare Patricia , Aullón Gabriel , Castillo Ivan 
Published: March 2013

AbstractA series of Cu+ complexes with ligands that feature varying numbers of benzimidazole/thioether donors and methylene or ethylene linkers between the central nitrogen atom and the thioether sulfur atoms have been spectroscopically and electrochemically characterized. Cyclic voltammetry measurements indicated that the highest Cu2+/Cu+ redox potentials correspond to sulfur‐rich coordination environments, with values decreasing as the thioether donors are replaced by nitrogen‐donating benzimidazoles. Both Cu2+ and Cu+ complexes were studied by DFT. Their electronic properties were determined by analyzing their frontier orbitals, relative energies, and the contributions to the orbitals involved in redox processes, which revealed that the HOMOs of the more sulfur‐rich copper complexes, particularly those with methylene linkers (NCH2S), show significant aromatic thioether character. Thus, the theoretically predicted initial oxidation at the sulfur atom of the methylene‐bridged ligands agrees with the experimentally determined oxidation waves in the voltammograms of the NS3‐ and N2S2‐type ligands as being ligand‐based, as opposed to the copper‐based processes of the ethylene‐bridged Cu+ complexes. The electrochemical and theoretical results are consistent with our previously reported mechanistic proposal for Cu2+‐promoted oxidative CS bond cleavage, which in this work resulted in the isolation and complete characterization (including by X‐ray crystallography) of the decomposition products of two ligands employed, further supporting the novel reactivity pathway invoked. The combined results raise the possibility that the reactions of copper–thioether complexes in chemical and biochemical systems occur with redox participation of the sulfur atom.
Detection of Hg2+ and F− Ions by Using Fluorescence Switching of Quantum Dots in an Au‐Cluster–CdTe QD Nanocomposite
Authors: Paramanik Bipattaran , Bhattacharyya Santanu , Patra Amitava 
Published: March 2013

AbstractA single probe of an Au nanocluster–CdTe quantum dots nanocomposite has been developed by using tripeptide‐capped CdTe quantum dots (QD) and bovine serum albumin (BSA) protein‐conjugated Au25 nanocluster (NC) for detection of both Hg2+ ion and F− ion. The formation of Au‐NC–CdTe QD nanocomposite has been confirmed by TEM, steady state and time resolved spectroscopy, CD and FTIR studies. A significant signal off (74 % PL quenching at 553 nm) phenomenon of this nanocomposite is observed in presence of 6.56×10−7 M Hg2+ ion, due to salt‐induced aggregation. However, a dramatic PL enhancement (128 %) of the Au‐NC–CdTe QD nanocomposite is observed in presence of 8.47×10−7 M F− anion. The calculated limit of detections (LOD) of Hg2+ ion concentration and F− ion concentration are found to be 9 and 117 nM, respectively, which are within the safety range set by the United States Environment Protection Agency. Thus, the simple Au‐NC–CdTe QD optical‐based sensor is very useful to detect both toxic cations and anions.
Electrospun Porous NiCo2O4 Nanotubes as Advanced Electrodes for Electrochemical Capacitors
Authors: Li Linlin , Peng Shengjie , Cheah Yanling , Teh Peifen , Wang Jin , Wee Grace , Ko Yahwen , Wong Chuiling , Srinivasan Madhavi 
Published: March 2013

AbstractNovel, porous NiCo2O4 nanotubes (NCO‐NTs) are prepared by a single‐spinneret electrospinning technique followed by calcination in air. The obtained NCO‐NTs display a one‐dimensional architecture with a porous structure and hollow interiors. The effect of precursor concentration on the morphologies of the products is investigated. Due to their unique structure, the prepared NCO‐NT electrode exhibits a high specific capacitance (1647 F g−1 at 1 A g−1), excellent rate capability (77.3 % capacity retention at 25 A g−1), and outstanding cycling stability (6.4 % loss after 3000 cycles), which indicates it has great potential for high‐performance electrochemical capacitors. The desirable enhanced capacitive performance of NCO‐NTs can be attributed to the relatively large specific surface area of these porous and hollow one‐dimensional nanostructures.
Lanthanide Contraction within a Series of Asymmetric Dinuclear [Ln2] Complexes
Authors: Aguilà David , Barrios Leoní A. , Velasco Verónica , Arnedo Leticia , Aliaga‐Alcalde Núria , Menelaou Melita , Teat Simon J. , Roubeau Olivier , Luis Fernando , Aromí Guillem 
Published: March 2013

AbstractA complete isostructural series of dinuclear asymmetric lanthanide complexes has been synthesized by using the ligand 6‐[3‐oxo‐3‐(2‐hydroxyphenyl)propionyl]pyridine‐2‐carboxylic acid (H3L). All complexes have the formula [Ln2(HL)2(H2L)(NO3)(py)(H2O)] (Ln=La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Tm (12), Yb (13), Lu (14), Y (15); py=pyridine). Complexes of La to Yb and Y have been crystallographically characterized to reveal that the two metal ions are encapsulated within two distinct coordination environments of differing size. Whereas one site maintains the coordination number (nine) through the whole series, the other one increases from nine to ten owing to a change in the coordination mode of an NO3− ligand. This series offers a unique opportunity to study in detail the lanthanide contraction within complexes of more than one metal. This analysis shows that various representative parameters proportional to this contraction follow a quadratic decay as a function of the number n of f electrons. Slater’s model for the atomic radii has been used to extract, from these decays, the shielding constant of 4f electrons. The average of O⋅⋅⋅O distances within the coordination polyhedra shared by both metals and of the Ln⋅⋅⋅Ln separations follow also a quadratic decay, therefore showing that such dependence holds also for parameters that receive the contribution of two lanthanide ions simultaneously. The magnetic behavior has been studied for all nondiamagnetic complexes. It reveals the effect of the spin–orbit coupling and a weak antiferromagnetic interaction between both metals. Photoluminescent studies of all the complexes in the series reveal a single broad emission band in the visible region, which is related to the coordinated ligand. On the other hand, the Nd, Er, and Yb complexes show features in the near‐IR region due to metal‐based transitions.
Microwave‐Induced In Situ Synthesis of Zn2GeO4/N‐Doped Graphene Nanocomposites and Their Lithium‐Storage Properties
Authors: Zou Feng , Hu Xianluo , Sun Yongming , Luo Wei , Xia Fangfang , Qie Long , Jiang Yan , Huang Yunhui 
Published: March 2013

AbstractZn2GeO4/N‐doped graphene nanocomposites have been synthesized through a fast microwave‐assisted route on a large scale. The resulting nanohybrids are comprised of Zn2GeO4 nanorods that are well‐embedded in N‐doped graphene sheets by in situ reducing and doping. Importantly, the N‐doped graphene sheets serve as elastic networks to disperse and electrically wire together the Zn2GeO4 nanorods, thereby effectively relieving the volume‐expansion/contraction and aggregation of the nanoparticles during charge and discharge processes. We demonstrate that an electrode that is made of the as‐formed Zn2GeO4/N‐doped graphene nanocomposite exhibits high capacity (1463 mAh g−1 at a current density of 100 mA g−1), good cyclability, and excellent rate capability (531 mAh g−1 at a current density of 3200 mA g−1). Its superior lithium‐storage performance could be related to a synergistic effect of the unique nanostructured hybrid, in which the Zn2GeO4 nanorods are well‐stabilized by the high electronic conduction and flexibility of N‐doped graphene sheets. This work offers an effective strategy for the fabrication of functionalized ternary‐oxide‐based composites as high‐performance electrode materials that involve structural conversion and transformation.
Dimeric Rare‐Earth BINOLate Complexes: Activation of 1,4‐Benzoquinone through Lewis Acid Promoted Potential Shifts
Authors: Robinson Jerome R. , Booth Corwin H. , Carroll Patrick J. , Walsh Patrick J. , Schelter Eric J. 
Published: March 2013

AbstractReaction of p‐benzoquinone (BQ) with a series of rare‐earth metal/alkali metal/1,1′‐BINOLate (REMB) complexes (RE: La, Ce, Pr, Nd; M: Li) results in the largest recorded shift in reduction potential observed for BQ upon complexation. In the case of cerium, the formation of a 2:1 Ce/BQ complex shifts the two‐electron reduction of BQ by greater than or equal to 1.6 V to a more favorable potential. Reactivity investigations were extended to other REIII (RE=La, Pr, Nd) complexes where the resulting highly electron‐deficient quinone ligands afforded isolation of the first lanthanide quinhydrone‐type charge‐transfer complexes. The large reduction‐potential shift associated with the formation of 2:1 Ce/BQ complexes illustrate the potential of Ce complexes to function both as a Lewis acid and an electron source in redox chemistry and organic‐substrate activation.
The Study of Biological Soil Crusts: Hotspots and Prospects
Authors: Bu Chongfeng , Wu Shufang , Xie Yongsheng , Zhang Xingchang 
Published: March 2013

AbstractBiological soil crusts (BSCs), which cover 35% of the continents and exceed 70% of the living cover in parts of region, play important ecological roles in the evolution of soil–water–plant systems in arid and semiarid areas. Since the 1980s, studies of BSCs have become hot topics in physical geography. By reviewing the last 30 years of study reports, the present paper proposes the following future research focus: (1) Understanding the function of BSCs in carbon and nitrogen fixation in the micro‐scale (block), monitoring its distribution patterns in the macro‐scale (region) by remote sensing technology and geographic information systems, and evaluate the role of carbon and nitrogen fixation in the whole ecological system. The response of BSCs to global climate change should also be evaluated. (2) Studying techniques for the artificial fast cultivation or restoration of BSCs, and implementing engineering propagation and application of artificial BSCs, and determining the appropriate parameters for environmental criteria, including light, temperature, soil water moisture, and fertilizer, among others. Artificial cultivation and rapid propagation techniques could present significant perspectives for engineering applications.
Biodegradability Assessment and Treatability of High Strength Complex Industrial Park Wastewater
Authors: Baban Ahmet 
Published: March 2013

AbstractIndustrial park wastewater (IPWW) includes complex non‐biodegradable organic compounds. A wastewater treatability study using biodegradability assessment approach was carried out for an industrial park housing mainly textile and machinery sectors. Biodegradable and inert chemical oxygen demand (COD) fractions with soluble and particulate counterparts were experimentally estimated by implementing respirometric methods. Aerobic batch test methods and oxygen uptake rate profiles were used to map kinetic parameters and COD fractions. Denitrification potential was also determined by application of anoxic batch tests. Relevant kinetic constants, stoichiometric, and design parameters were determined for biological processes. Tests were carried out for raw and physico‐chemically pre‐treated IPWW. Hence, it was aimed to assess the effects and necessity of pre‐treatment on biological processes. Biological mineralization, nitrification, and denitrification processes were also designed and tested using a bench scale continuous treatment model for pre‐treated IPWW. The sum of initial inert soluble COD fraction and production of soluble microbial products decreased about 25% for the case of pre‐treated IPWW as compared to raw IPWW. Eighty‐three percent total COD and 89% total Kjeldahl nitrogen removal efficiencies were attained for the modeling experiments of pre‐treated IPWW. Results showed the significance of pre‐treatment if complex strength industrial wastewaters are to be biologically treated.
Preparation of Nano‐Lepidocrocite and an Investigation of Its Ability to Remove a Metal Complex Dye
Authors: Sheydaei Mohsen , Aber Soheil 
Published: March 2013

AbstractLepidocrocite (γ‐FeOOH) nanoparticles were synthesized from iron(II) sulfate solution and characterized using X‐ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform‐IR (FT‐IR), nitrogen adsorption, and point of zero charge pH (pHPZC) analyses. TEM, XRD, and FT‐IR analyses proved the synthesis of nano‐lepidocrocite. Surface area and pHPZC of the synthesized lepidocrocite were 68.1 m2 g−1 and 4.8, respectively. Utilization of the synthesized lepidocrocite in the adsorption of Lanacron brown S‐GL (LBS‐GL) from aqueous solutions was investigated, and the effect of lepidocrocite dosage, pH, temperature, and contact time on this process were optimized and modeled using response surface methodology approach. The lepidocrocite dosage of 0.015 g, pH 3.5, temperature of 38°C, and contact time of 100 min were determined as optimum adsorption conditions. Isotherm and kinetics of the adsorption process were analyzed at the optimum conditions. The equilibrium data were fitted well to the Langmuir isotherm model. The maximum monolayer adsorption capacity was 528.21 mg g−1. The adsorption process was described by the pseudo‐second‐order kinetic model. Furthermore, the effect of pH on the desorption of LBS‐GL was investigated. High LBS‐GL desorption efficiency was achieved at a high pH value.