bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combining differential quadrature method with simulation technique to solve non‐linear differential equations
Authors: Girgin Zekeriya 
Published: January 2008

AbstractNowadays, most of the ordinary differential equations (ODEs) can be solved by modelica‐based approaches, such as Matlab/Simulink, Dymola and LabView, which use simulation technique (ST). However, these kinds of approaches restrict the users in the enforcement of conditions at any instant of the time domain. This limitation is one of the most important drawbacks of the ST. Another method of solution, differential quadrature method (DQM), leads to very accurate results using only a few grids on the domain. On the other hand, DQM is not flexible for the solution of non‐linear ODEs and it is not so easy to impose multiple conditions on the same location. For these reasons, the author aims to eliminate the mentioned disadvantages of the simulation technique (ST) and DQM using favorable characteristics of each method in the other. This work aims to show how the combining method (CM) works simply by solving some non‐linear problems and how the CM gives more accurate results compared with those of other methods. Copyright © 2008 John Wiley & Sons, Ltd.
Application of the higher‐order Cauchy–Born rule in mesh‐free continuum and multiscale simulation of carbon nanotubes
Authors: Sun Yuzhou , Liew K. M. 
Published: January 2008

AbstractThis paper investigates the application of a recently proposed higher‐order Cauchy–Born rule in the continuum simulation and multiscale analysis of carbon nanotubes (CNTs). A mesh‐free computational framework is developed to implement the numerical computation of the hyper‐elastic constitutive model that is derived from the higher‐order Cauchy–Born rule. The numerical computation reveals that the buckling pattern of a single‐walled carbon nanotube (SWCNT) can be accurately displayed by taking into consideration the second‐order deformation gradient, and fewer mesh‐free nodes can provide a good simulation of homogeneous deformation. The bridging domain method is employed to couple the developed mesh‐free method and the atomistic simulation. The coupling method is used to simulate the bending buckling of an SWCNT and the tensile failure of an SWCNT with a single‐atom vacancy defect, and good computational results are obtained. Copyright © 2008 John Wiley & Sons, Ltd.
Automated technologies and novel techniques to accelerate protein crystallography for structural genomics
Authors: Manjasetty Babu A. , Turnbull Andrew P. , Panjikar Santosh , Büssow Konrad , Chance Mark R. 
Published: January 2008

AbstractThe sequence infrastructure that has arisen through large‐scale genomic projects dedicated to protein analysis, has provided a wealth of information and brought together scientists and institutions from all over the world. As a consequence, the development of novel technologies and methodologies in proteomics research is helping to unravel the biochemical and physiological mechanisms of complex multivariate diseases at both a functional and molecular level. In the late sixties, when X‐ray crystallography had just been established, the idea of determining protein structure on an almost universal basis was akin to an impossible dream or a miracle. Yet only forty years after, automated protein structure determination platforms have been established. The widespread use of robotics in protein crystallography has had a huge impact at every stage of the pipeline from protein cloning, over‐expression, purification, crystallization, data collection, structure solution, refinement, validation and data management‐ all of which have become more or less automated with minimal human intervention necessary. Here, recent advances in protein crystal structure analysis in the context of structural genomics will be discussed. In addition, this review aims to give an overview of recent developments in high throughput instrumentation, and technologies and strategies to accelerate protein structure/function analysis.
Kinetics and mechanism of the reaction between 4‐hexadecylbenzenediazonium ions and vitamin C in emulsions: further evidence of the formation of diazo ether intermediates in the course of the reaction
Authors: Pastoriza‐Gallego María José , Fernández‐Alonso Alejandra , Losada‐Barreiro Sonia , Sánchez‐Paz Verónica , Bravo‐Díaz Carlos 
Published: January 2008

AbstractThe kinetics and mechanism of the reaction between hydrophobic 4‐hexadecylarenediazonium ions, 16‐ArN and vitamin C, VC, in a model emulsion prepared by mixing octane, acidic (HCl) water and the non‐ionic surfactant hexaethyleneglycol monododecyl ether, C12E6, were investigated. Because emulsions are opaque, linear sweep voltammetry, LSV, was employed to monitor the reaction. Voltammograms of 16‐ArN in emulsions show two reduction peaks as in aqueous systems. The half‐life for the spontaneous decomposition of 16‐ArN in the emulsion was estimated as t1/2 = 14.5 h at T = 25 °C. Upon addition of VC to the system, the first reduction peak of 16‐ArN disappears almost immediately and a new reduction peak is detected at Ep = −0.25 V. Electrochemical titration of 16‐ArN shows that the new peak corresponds to the formation of a 1:1 adduct. The iP(Ep = −0.25 V) values can be linearly correlated with [16‐ArN] and the observed rate constants, kobs, were determined by fitting the (ip, t) data to the integrated first order equation. The variation of kobs with [VC] follows a saturation kinetics profile, consistent with the formation of an intermediate in a pre‐equilibrium step. All the evidence is consistent with a reaction mechanism comprising two competitive pathways, the spontaneous DN + AN mechanism and the unimolecular decomposition of a transient diazo ether (DE) formed in a pre‐equilibrium step. The data allowed estimations of the interfacial rate constant for the reaction between 16‐ArN and VC− but did not allow the determination of the equilibrium constant for the DE formation. Copyright © 2008 John Wiley & Sons, Ltd.
Identification of 2,3‐dimethyl‐2,3‐diisobutyl succinonitrile in laser printer emissions
Authors: Barrero‐Moreno Josefa M. , Tirendi Salvatore , Reniero Fabiano , Giordano Giuseppe , Kotzias Dimitrios 
Published: January 2008

Abstract2,3‐Dimethyl‐2,3‐diisobutyl succinonitrile was identified as the main volatile organic compound (>90%) emitted from laser printers during the printing process. Experiments were carried out in a large environmental chamber of 30 m3, where the printers were placed and working simulating ‘real office setting’ conditions. Air samples were taken on Tenax TA adsorbent cartridges in the vicinity of the printers and further analyzed by thermal desorption gas chromatography/mass spectrometry (TDGC/MS). The structure of the compound has been determined and is presented in this study. Additional data obtained by nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, and liquid chromatography/tandem mass spectrometry (LC/MS/MS) support the proposed structure, with no reported CAS number, as 2,3‐dimethyl‐2,3‐diisobutyl succinonitrile. It is a byproduct of the thermal decomposition of 2,2′‐azobis(2,4‐dimethyl valeronitrile), a commercially available free radical polymerization initiator used in polymerization processes during the manufacture of the toners. By means of head‐space GC/MS, 15 toners used in black & white and colour printers have been investigated. Six of them contained 2,3‐dimethyl‐2,3‐diisobutyl succinonitrile, which has also been detected in the respective processed paper. Copyright © 2008 John Wiley & Sons, Ltd.
On the globally defined sensorless control of induction motors
Authors: Guerrero C. , Espinosa‐Pérez G. , Moreno J. A. , Álvarez‐Salas R. 
Published: January 2008

AbstractThe sensorless control problem of induction motors imposes a current challenge since the nonlinear model of this kind of machines does not exhibit global observability properties, i.e. there are some operation regimes for which speed observability is lost. One way for dealing with this unavoidable limitation, and at the same time provide globally defined controllers, is to consider that the rotor variables are estimated via an open‐loop observer. In this paper a globally defined passivity‐based speed controller that belongs to the aforementioned class is presented. It is shown that the structure of previously reported passivity‐based controllers, developed under the assumption that the mechanical variables are available for measurement, can be extended to operate under sensorless conditions if a speed observer is included in the control scheme. Since the controller design methodology leads to inherent drawbacks regarding robustness issues, to evaluate the usefulness of the proposed scheme a numerically based study is included that cover topics such as parameters and disturbance (load torque) uncertainty. The advantages and limitations of the proposed scheme are established with respect to other globally defined sensorless controllers. Copyright © 2008 John Wiley & Sons, Ltd.
A new controller for the inverted pendulum on a cart
Authors: Gordillo F. , Aracil J. 
Published: January 2008

AbstractThis paper presents a complete solution to the problem of swinging‐up and stabilization of the inverted pendulum on a cart, with a single control law. The resulting law has two parts: first, an energy‐shaping law is able to swing and maintain the pendulum up. Then, the second part introduces additional control to stop the cart and it is based on forwarding control with bounded input. The resulting control law is the sum of both parts and does not commute between different laws although there exist switches inside the controller. Copyright © 2008 John Wiley & Sons, Ltd.
ANODIC formation of thin Cu(I) and Ag(I) oxide films on Cu‐Au and Ag—Au alloys
Authors: Vvedenskii Alexander , Grushevskaya Svetlana , Kudryashov Dmitrii 
Published: January 2008

AbstractThe anodic dissolution of Cu, Ag and their alloys with gold under the conditions of the formation of copper or silver oxides was examined by the technique of cyclic voltammetry, chronoammetry and photopotential measurements. The anodic formation and cathodic reduction of Cu(I) oxide on copper and Cu‐Au alloys or Ag(I) oxide on silver and Ag‐Au alloys with XAu≤30 at.% are controlled by migration in the oxide film. The peculiarity of Ag‐Au system is connected with the duplex structure of the oxide film and the initial selective dissolution of silver from Ag15Au and Ag30Au alloys. Ag2O oxide is an n‐type semiconductor with an excess of silver atoms. Oxide layers formed on monocrystalline silver are more stoichiometric than the layer formed on polycrystalline Ag. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation, Crystal Structure, Physical Properties and Electronic Band Structure of TlScQ2 (Q = S, Se and Te)
Authors: Teske Christoph L. , Bensch Wolfgang , Mankovsky Sergey , Ebert Hubert 
Published: January 2008

AbstractThe title compounds were prepared by reaction of Tl2Q (Q = S, Se and Te) Sc and Q in the temperature range of 200 to 500 °C. The structures of the selenide and the telluride adopt the α‐NaFeO2 type, while TlScS2 crystallizes in the β‐RbScO2 type structure. The space group is $\rm R{\bar 3}\rm m$ for TlScSe2 and TlScTe2 with a = 3.9370(4) Å, c = 23.194(5) Å, and a = 4.2129(4) Å, c = 24.099(3) Å, respectively. The sulphide crystallizes in P63/mmc with a = 3.761(3) Å and c = 14.942(4) Å. The crystal chemical relations between the three chalcogenides are discussed. According to the electrical measurements and the band structure calculations, the compounds are semiconductors or poor metals.
Trivalent‐Intermediate Valent Cerium Ordering in Ce2RuZn4
Authors: Mishra Ratikanta , Hermes Wilfried , Rodewald Ute Ch. , Hoffmann Rolf‐Dieter , Pöttgen Rainer 
Published: January 2008

AbstractThe new intermetallic cerium compound Ce2RuZn4 was synthesized from the elements in a sealed tantalum tube in a water‐cooled sample chamber of an induction furnace. Ce2RuZn4 crystallizes with a new structure type: P4/nmm, Z = 2, a = 719.6(1), c = 520.2(1) pm, wR2 = 0.0816, 273 F2 values and 15 variables. The structure contains two crystallographically independent cerium atoms: Ce1 with CN 16 (12 Zn + 4 Ce) and Ce2 with CN 14 (2 Ru + 8 Zn + 4 Ce). Based on the interatomic distances the two sites can be assigned to trivalent Ce1 and intermediate valent Ce2. The trivalent‐intermediate valent cerium ordering is underlined by magnetic susceptibility measurements. Ce2RuZn4 shows modified Curie‐Weiss behaviour in the temperature range 10–290 K with an experimental magnetic moment of 2.57(1) μB per formula unit. Thus only half of the cerium atoms are trivalent in Ce2RuZn4. A remarkable feature of the Ce2RuZn4 structure are short Ce2–Ru distances of 260 pm. The crystal chemistry of Ce2RuZn4 is discussed.
Supramolecular Stuctures from Mononuclear, Binuclear and 2D Net of Copper(II) Complexes with 6‐Hydroxypicolinic Acid
Authors: Sun Chang‐Yan , Zhou Jie , Li Wen‐Jun , Jin Lin‐Pei 
Published: January 2008

AbstractFirst examples of transition metal complexes with HpicOH [Cu(picOH)2(H2O)2] (1), [Cu(picO)(2,2′‐bpy)]·2H2O (2), [Cu(picO)(4,4′‐bpy)0.5(H2O)]n (3), and [Cu(picO)(bpe)0.5(H2O)]n (4) (HpicOH = 6‐hydroxy‐picolinic acid; 2,2′‐bpy = 2,2′‐bipyridine; 4,4′‐bpy = 4,4′‐bipyridine; bpe = 1,2‐bis(4‐pyridyl)ethane) have been synthesized and characterized by single‐crystal X‐ray diffraction. The results show that HpicOH ligand can be in the enol or ketonic form, and adopts different coordination modes under different pH value of the reaction mixture. In complex 1, HpicOH ligand is in the enol form and adopts a bidentate mode. While in complexes 2–4, as the pH rises, HpicOH ligand becomes in the ketonic form and adopts a tridentate mode. The coordination modes in complexes 1–4 have not been reported before. Because of the introduction of the terminal ligands 2,2′‐bpy, complex 2 is of binuclear species; whereas in complexes 3 and 4, picO ligands together with bridging ligands 4,4′‐bpy and bpe connect CuII ions to form 2D nets with (123)2(12)3 topology.
Synthesis and Crystal Structure of an Oligomeric Lithium Bis(amido)hydridooxidoaluminate Cluster, [{Li(C14H30N2)AlHO1/2}4]
Authors: Gardiner Michael G. , Raston Colin L. 
Published: January 2008

AbstractThe lithium bis(amido)hydridooxidoaluminate cluster [{Li(C14H30N2)AlHO1/2}4] has been synthesized during systematic metallation/hydrometallation studies of a series of 1,4‐diazabut‐1‐enes with lithium aluminiumhydride. Formation of the complex is presumably derived from partial hydrolysis of the related lithium bis(amido)dihydridoaluminate and has been characterized using single crystal X‐ray diffraction. The complex crystallizes in the monoclinic space group C2/c (No. 15) with a = 25.012(2) Å, b = 10.673(2) Å, c = 28.673(3) Å, β = 115.855(7)°, V = 6887(1) Å3, Z = 4. The complex exhibits an oligomeric structure of crystallographic C2 symmetry, comprised of complex multicyclic units arising from extensive metal, hydride, oxide and ligand bridging interactions. These associations give rise to edge‐fused, non‐planar NAlOLi four‐membered rings tightly binding two of the diamido‐chelated aluminate units, with these in turn aggregating further via two of the μ2‐hydrides involving lithium atoms.
Synthesis, Crystal Structure, and Emission Spectra of Lanthanum(III) Coordination Polymer with 1,5‐Naphthalenedisulfonate Ligand
Authors: Deng Zhao‐Peng , Gao Shan , Zhu Zhi‐Biao , Huo Li‐Hua 
Published: January 2008

AbstractThe first two‐dimensional lanthanum(III) coordination polymer, [La(1,5‐NDS)1.5(H2O)5]n (1) (1,5‐NDS2− = 1,5‐naphthalenedisulfonate), was synthesized and structurally characterized by single‐crystal X‐ray diffraction analysis. The disulfonate ligands act in the η1:η1:μ2 and η1:η1:η1:μ3 binding modes to link the LaO9 tricapped trigonal prisms into a lamellar structure. It exhibits strong purple emission in the solid state.
Clinical Application of Layered Anastomosis During Esophagogastrostomy
Authors: Zhu Zi‐Jiang , Zhao Yong‐Fan , Chen Long‐Qi , Hu Yang , Liu Lun‐Xu , Wang Yun , Kou Ying‐Li 
Published: January 2008

AbstractThe aim of this study was to compare the operative results in regard to reducing anastomotic leakage and stricture formation using a newly designed layered manual esophagogastric anastomosis versus a stapler esophagogastrostomy versus the conventional hand‐sewn whole‐layer anastomosis after resection for esophageal or gastric cardiac carcinoma. From January 2004 to September 2006, a total of 1024 patients with esophageal or gastric cardia carcinoma underwent a layered esophagogastric anastomosis with the assistance of a three‐leaf clipper in a single university medical center. The mucosal layers of the esophagus and stomach were sutured continuously with 4/0 Vicryl plus antibacterial suture (polyglyconate). From May 2002 to December 2003, there were also 170 patients and 69 patients who underwent stapler and conventional whole‐layer anastomosis, respectively; they served as control groups. The results were analyzed retrospectively. The operative mortality rate was 0.7% in the layered group compared to 5.9% and 7.2% for the stapler group and the whole‐layer group (p < 0.01), The anastomotic leakage rates were 0%, 3.5%, and 5.8% for the layered group, stapler group, and whole‐layer group, respectively (p < 0.01). All patients were followed postoperatively. Six patients in the layered group (0.6%) developed mild stricture formation compared to 16 patients in stapled group (9.9%) and 5 patients in the conventional whole‐layer group (7.8%) (p < 0.01). The application of layered esophagogastric anastomosis could reduce the incidence of anastomotic leakage and stricture after esophagectomy compared with the stapler and whole‐layer manual anastomoses. It is easy to apply and could be used as an alternative for esophagogastric anastomosis after resection for esophageal or cardiac carcinoma.
Bacterial population dynamics and faecal short-chain fatty acid (SCFA) concentrations in healthy humans
Authors: McOrist Alexandra L. , Abell Guy C. J. , Cooke Caroline , Nyland Kerry 
Published: January 2008

Fermentation products, SCFA, particularly butyrate, are considered a sign of ‘good’ bowel health but the influence of bacterial population composition and diet on inter-individual difference in metabolites and colonic health is poorly understood. Faecal specimens were collected weekly from eight healthy human volunteers over 12 weeks. Dietary intake was self-reported and ten macronutrient factors were analysed at selected weekly periods. Faecal weight, pH and moisture were recorded, and SCFA concentrations were measured in all samples. From each specimen, DNA was prepared and eubacterial 16S rRNA gene PCR performed. Bacterial population profiles were captured by denaturing gradient gel electrophoresis (DGGE) of PCR products, and multivariate statistical analysis was performed. Faecal weight, pH and moisture varied widely within and between individuals. Average total SCFA concentrations over 12 weeks ranged from 36·9 to 144·4 mmol/kg in 48 h specimens and faecal butyrate concentrations ranged from 1·8 to 48·5 mmol/kg. Two individuals with butyrate concentrations below 10 mmol/kg were considered to be ‘low butyrate types’ and may represent an at-risk population for bowel health. Dietary fat, sugar and carbohydrate showed weak correlation with SCFA (R− 0·612,P = 0·015;R0·607,P = 0·016;R0·610,P = 0·016, respectively) and butyrate concentrations (R− 0·593,P = 0·02;R0·504,P = 0·054;R0·528,P = 0·043, respectively). Multivariate analysis of DGGE bacterial profiles demonstrated concise and repeated grouping of intra-individual samples, but these were combined with distinct inter-individual differences (analysis of similaritiesP < 0·001,R ≥ 0·99) The exact relationship of these SCFA values to the overall bacterial profiles and SCFA-producer bacterial groups was not direct nor linear.
An arachidonic acid-enriched diet does not result in more colonic inflammation as compared with fish oil- or oleic acid-enriched diets in mice with experimental colitis
Authors: Ramakers Julian D. , Mensink Ronald P. , Verstege Marleen I. , te Velde Anje A. , Plat Jogchum 
Published: January 2008

Fish oils (FO) – rich in EPA and DHA – may protect against colitis development. Moreover, inflammatory bowel disease patients have elevated colonic arachidonic acid (AA) proportions. So far, effects of dietary AAv.FO on colitis have never been examined. We therefore designed three isoenergetic diets, which were fed to mice for 6 weeks preceding and during 7 d dextran sodium sulfate colitis induction. The control diet was rich in oleic acid (OA). For the other two diets, 1·0 % (w/w) OA was exchanged for EPA+DHA (FO group) or AA. At 7 d after colitis induction, the AA group had gained weight (0·46 (sem0·54) g), whereas the FO and OA groups had lost weight ( − 0·98 (sem0·81) g and − 0·79 (sem1·05) g, respectively;P < 0·01v.AA). The AA group had less diarrhoea than the FO and OA groups (P < 0·05). Weight and length of the colon, histological scores and cytokine concentrations in colon homogenates showed no differences. Myeloperoxidase concentrations in plasma and polymorphonuclear cell infiltration in colon were decreased in the FO group as compared with the OA group. We conclude that in this mice model an AA-enriched diet increased colonic AA content, but did not result in more colonic inflammation as compared with FO- and OA-enriched diets. As we only examined effects after 7 d and because the time point for evaluating effects seems to be important, the present results should be regarded as preliminary. Future studies should further elucidate differential effects of fatty acids on colitis development in time.
The distribution ofFasciola hepaticaandFasciola giganticawithin southern Tanzania – constraints associated with the intermediate host
Authors: WALKER S. M. , MAKUNDI A. E. , NAMUBA F. V. , KASSUKU A. A. , KEYYU J. , HOEY E. M. , PRÖDOHL P. , STOTHARD J. R. , TRUDGETT A. 
Published: January 2008

SUMMARYIn East Africa,Fasciola giganticais generally the causative agent of fasciolosis but there have been reports ofF. hepaticain cattle from highland regions of Kenya, Ethiopia, Uganda and Zaire. The topography of the Southern Highlands of Tanzania provides an environment where the climatic conditions exist for the sustenance of lymnaeid species capable of supporting bothFasciola hepaticaandF. gigantica. Theoretically this would allow interaction between fasciolid species and the possible creation of hybrids. In this report we present molecular data confirming the existence of the snail,Lymnaea truncatula, at high altitude on the Kitulo Plateau of the Southern Highlands, Tanzania, along with morphometric and molecular data confirming the presence ofF. hepaticain the corresponding area. At lower altitudes, where climatic conditions were unfavourable for the existence ofL. truncatula, the presence of its sister speciesL. natalensiswas confirmed by molecular data along with its preferred fasciolid parasite,F. gigantica. Analysis based on a 618 bp sequence of the 28S rRNA gene did not reveal the presence of hybrid fasciolids in our fluke samples.