bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exact elliptic compactons in generalized Korteweg–De Vries equations
Authors: Cooper Fred , Khare Avinash , Saxena Avadh 
Published: August 2006

AbstractUsing the action principle, and assuming a solitary wave of the generic form u(x,t) = AZ(β(x + q(t)), we derive a general theorem relating the energy, momentum, and velocity of any solitary wave solution of the generalized Korteweg‐De Vries equation K*(l,p). Specifically we find that
${\dot q}=r(l,p)H/P$, where l,p are nonlinearity parameters. We also relate the amplitude, width, and momentum to the velocity of these solutions. We obtain the general condition for linear and Lyapunov stability. We then obtain a two‐parameter family of exact solutions to these equations, which include elliptic and hyper‐elliptic compacton solutions. For this general family we explicitly verify both the theorem and the stability criteria. © 2006 Wiley Periodicals, Inc. Complexity 11: 30–34, 2006
Co‐existence of Poisson and non‐Poisson processes in ordered parallel multilane pedestrian traffic
Authors: Bantang Johnrob , Saloma Caesar 
Published: August 2006

AbstractWe show that non‐Poisson and Poisson processes can coexist in ordered parallel multilane pedestrian traffic, in the presence of lane switching which asymmetrically benefits the switchers and nonswitchers. Pedestrians join at the tail end of a queue and transact at the opposite front end. Their aim is to complete a transaction within the shortest possible time, and they can transfer to a shorter queue with probability ps. Traffic is described by the utilization parameter U = λ〈ts〉/N, where λ is the average rate of pedestrians entering the system, 〈ts〉 is the average transaction time, and N is the number of lanes. Using an agent‐based model, we investigate the dependence of the average completion time 〈tc〉 with variable K = 1 + (1 − U)−1 for different N and 〈ts〉 values. In the absence of switching (ps = 0), we found that 〈tc〉 ∝ Kτ, where τ ≈ 1 regardless of N and 〈ts〉. Lane switching (ps = 1) reduces 〈tc〉 for a given K, but its characteristic dependence with K differs for nonswitchers and switchers in the same traffic system. For the nonswitchers, 〈tc〉 ∝ Kτ, where τ < 1. At low K values, switchers have a larger 〈tc〉 that also increases more rapidly with K. At large K, the increase rates become equal for both. For nonswitchers, the possible tc values obey an exponentially decaying probability density function p(tc). The switchers on the other hand, are described by a fat‐tailed p(tc) implying that a few are penalized with tc values that are considerably longer than any of those experienced by nonswitchers. © 2006 Wiley Periodicals, Inc. Complexity 11: 35–42, 2006
Social percolation in relations between activists and supporters
Authors: Takahashi Kazuyuki Ikko , Murai Ryousuke 
Published: August 2006

AbstractThis article is a study of the relations between activists with a strong belief and their passive supporters. In order to achieve a fuller understanding of these relations the authors make use of bond percolation theory. The theories hold that when the size of a group's communication in a given society exceeds a critical threshold; that is, when the size of the cluster of supporters' bonds becomes practically infinite within the society by virtue of the work of activists, subsequently supporters and activists come to hold key positions in society. A graph is generated indicating the probability of activists' bonds with respect to the probability of supporters' bonds within a lattice, when the biggest cluster of supporters' bonds becomes infinite. Simulations have been undertaken, and when a case is found in which infinite clusters emerge, this value of the probability of both supporters' and activists' bonds is isolated. A graph can then be generated a graph on which to plot these values as points. After that, these results can be discussed at length and some conclusions are derived from them. © 2006 Wiley Periodicals, Inc. Complexity 11: 51–56, 2006
Quantitative assessment of right and left reaching movements in infants: A longitudinal study from 6 to 36 months
Authors: Rönnqvist Louise , Domellöf Erik 
Published: August 2006

AbstractThis longitudinal study aimed to explore the early presence and developmental pattern of laterality in reaching kinematics and its relationship to side use. In order to do so, 3‐D kinematic measurements as well as 2‐D video recordings of right‐left reaching movements were successively carried out for 17 infants at the ages of 6, 9, 12, and 36 months. Additional investigations of hand preference were made at 36 months. As four infants were prematurely born, their outcomes were compared to those of the fullterm participants. While most of the infants in the early ages showed a rather inconsistent preference in terms of frequency and distributions of right‐left side use, the analyses of reaching kinematics revealed a more consistent pattern of fewer movements units (MUs) and straighter right‐sided reaching for the majority of infants at all tested ages. However, reaching kinematics from the preterm infants were generally more variable and less side consistent. It is proposed that the development of human handedness originates from an early right arm rather than hand preference in that representations of asymmetry in bilateral projections (involved in arm movements) developmentally precede contralateral projections (involved in refined hand/finger movements). © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 444–459, 2006.
Agenesis of the corpus callosum and the establishment of handedness
Authors: Sacco Silvia , Moutard Marie‐Laure , Fagard Jacqueline 
Published: August 2006

AbstractThe goal of this study was to check whether an isolated agenesis of the corpus callosum, detected in utero with ultrasound recording, would impair the early development of unimanual and bimanual handedness. Twelve infants with isolated agenesis of the corpus callosum, either total (TACC) or partial (PACC) were tested for handedness at the end of their first year, and were compared to infants with typical development (TD), matched for age and sex. A majority of infants showed right‐handedness at the unimanual grasping tasks, with no significant difference between the TD and ACC groups. When the object was presented to the left, the TACC infants were more likely to grasp the object with their right hand (with or without the left hand) than both the TD and the PACC infants who used mostly the ipsilateral left hand. The only significant difference between TD and ACC infants concerned bimanual coordination, as less ACC infants (especially TACC) succeeded at the bimanual task, compared with TD infants. In addition, the strategy of the former tended to be less right‐handed than that of the latter. Our results confirm the role of the CC in bimanual coordination, indicating that the early emergence of bimanual coordination and, if confirmed, bimanual handedness, are likely to be delayed in the absence of corpus callosum, especially if agenesis is total. They do not support the idea that the CC is necessary for the early onset of handedness. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 472–481, 2006.
Laterality in persons with intellectual disability II. Hand, foot, ear, and eye laterality in persons with Trisomy 21 and Williams‐Beuren syndrome
Authors: Gérard‐Desplanches Aude , Deruelle Christine , Stefanini Silvia , Ayoun Catherine , Volterra Virginia , Vicari Stefano , Fisch Gene , Carlier Michèle 
Published: August 2006

AbstractLaterality (hand, foot, ear, and eye) was assessed in participants with Trisomy 21 (62) and Williams–Beuren syndrome (WBS) (39). Handedness was also assessed in a card reaching task. The comparison group included 184 typically developing persons. Two independent age sub‐groups were formed: 7 to 10 years old and 11 to 34 years old. We confirmed previous data: individuals with T21 were more frequently left‐ or mixed‐handed than typically developing persons; individuals with WBS had intermediate scores. The two groups with genetic disorders had less right foot preference. Manual and foot inconsistencies characterized both groups with genetic disorders. Cross hand–foot preference was lower in the typically developing group. Differences in IQ levels did not correlate with differences in laterality scores. Overall laterality profiles were not the same in the two groups with genetic disorders: the greatest differences were observed between typically developing persons and persons with Trisomy 21. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 482–491, 2006.
Parental and perinatal factors influencing the development of handedness in captive chimpanzees
Authors: Hopkins William D. , Wesley Michael J. , Russell Jamie L. , Schapiro Steven J. 
Published: August 2006

AbstractIt has been proposed that human right handedness is determined by genetic factors associated with the emergence of language, whereas non‐human primate handedness is determined by random, non‐genetic factors. These different mechanisms account for differences in the distribution of handedness between human and non‐human primates. Here we report evidence that genetic factors play a role in the determination of handedness in chimpanzees. We further report that differential rearing has no influence on the expression of handedness in related individuals. Contrary to many theories of the origin of handedness, these results indicate that genetic factors have a significant influence on handedness in chimpanzees. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 428–435, 2006.
Dyslexia at a behavioural and a cognitive level
Authors: Helland Turid 
Published: August 2006

AbstractThe aim of this study was to see whether patterns of neuro‐cognitive assets and deficits seen in dyslexia also would lead to different patterns of reading and writing. A group of dyslexic children was subgrouped by language comprehension and mathematics skills in accordance with the definition of the British Dyslexia Association of 1998. This yielded three subgroups that showed three distinct neuro‐cognitive profiles depicted within the Multi‐Component Model of Working Memory. The participants were tested with single word reading and spelling tasks. The scores varied only to a minor degree between the subgroups. The results were discussed in view of developmental phases into literacy. Only one subgroup could be defined within the orthographic phase, while the other two were within the alphabetic phase. Thus, patterns at the neuro‐cognitive level seen in the subgroups were to a limited degree reflected at the behavioural level. The results were also discussed in view of different orthographies. Since using information from phonological testing only, as currently appears to be common practice in many contexts, may result in intervention with little effect for some dyslexics, it was concluded that assessing neuro‐cognitive assets and deficits targeting dyslexia is essential to intervention and the understanding of dyslexia. Copyright © 2006 John Wiley & Sons, Ltd.
Language‐related differences between discrepancy‐defined and non‐discrepancy‐defined poor readers: a longitudinal study of dyslexia in New Zealand
Authors: Tunmer William E. , Chapman James W. 
Published: August 2006

AbstractLanguage‐related differences between discrepancy‐defined and non‐discrepancy‐defined poor readers were examined in a three‐year longitudinal study that began at school entry. The discrepancy‐defined (dyslexic) poor readers (n = 19) were identified in terms of poor reading comprehension and average or above average listening comprehension performance, and the non‐discrepancy‐defined (non‐dyslexic) poor readers (n = 19) in terms of both poor reading and listening comprehension performance. The two poor reader groups and a group of normally developing readers (n = 55) were given several oral language, phonological processing, and reading performance measures at six testing occasions. Results indicated that in addition to expected differences on the oral language measures, the non‐discrepancy‐defined poor readers also showed greater phonological processing deficits than the dyslexic poor readers. The results are discussed in terms of the lack of official recognition of dyslexia in New Zealand, the whole language orientation of classroom reading instruction, and the inadequacy of Reading Recovery for minimizing reading problems. Copyright © 2006 John Wiley & Sons, Ltd.
La17Si9Al4N32–xOx (x ≤ 1): A Nitridoaluminosilicate with Isolated Si/Al‐N/O Clusters
Authors: Pilet Guillaume , Grins Jekabs , Edén Mattias , Esmaeilzadeh Saeid 
Published: August 2006

AbstractA nitrogen‐rich aluminosilicate with nominal composition La17Si9Al4N33 has been synthesised at 1500–1650 °C under a N2 atmosphere by reaction of La metal, AlN and Si3N4. Its crystal structure was solved and refined in space group F3m, with a = 15.4279(6) Å and Z = 4, to Rf = 1.9 %. The structure contains two novel types of discrete tetrahedral aluminosilicate clusters, with respective nominal compositions Al4Si4N17 and Si5N16, with La atoms in between. Bulk samples were also investigated by powder X‐ray and electron diffraction. The 29Si and 27Al solid‐state NMR results indicate that the phase contains minor amounts of oxygen and has a narrow compositional range with probable end limits La17Si9Al4N33 and La16.67Si9Al4N32O.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Electroluminescence Properties of fac‐Tris(2‐phenylpyridine)iridium Derivatives Containing Hole‐Trapping Moieties
Authors: Ono Katsuhiko , Joho Michitoshi , Saito Katsuhiro , Tomura Masaaki , Matsushita Yosuke , Naka Shigeki , Okada Hiroyuki , Onnagawa Hiroyoshi 
Published: August 2006

AbstractIn order to investigate an effective method for carrier injection into the phosphor of organic electroluminescent (EL)devices, we synthesized fac‐tris(2‐phenylpyridine)iridium [Ir(ppy)3] derivatives containing hole‐trapping moieties, such as diphenylamine, carbazole, and phenoxazine. Their photoluminescent maxima were observed around the maximum of Ir(ppy)3. These values were slightly shifted depending on the hole‐trapping moieties: redshifted due to diphenylamine and blueshifted due to carbazole and phenoxazine. Further, these moieties affected the oxidation potentials of Ir complexes in cyclic voltammetry. EL devices using an Ir complex with diphenylamine exhibited high EL performance because 1,1‐bis[4‐(di‐p‐tolylamino)phenyl]cyclohexane (TAPC) was employed as a hole‐transporting layer. The maximum external quantum efficiency (ηext) was recorded as 12.2 %. This value is comparable to that observed in a device using Ir(ppy)3. These results indicate that the diphenylamino substituent is favorable to serve as a hole‐trapping moiety of Ir(ppy)3. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Galactose Oxidase Models: Creation and Modification of Proton Transfer Coupled to Copper(II) Coordination Processes in Pro‐Phenoxyl Ligands
Authors: Michel Fabien , Thomas Fabrice , Hamman Sylvain , Philouze Christian , Saint‐Aman Eric , Pierre Jean‐Louis 
Published: August 2006

AbstractTwo tripodal ligands containing two pyridyl and one 4‐(benzimidazol‐2‐yl)‐2‐tert‐butylphenol (HLH) and one 2‐tert‐butyl‐4‐(N‐methylbenzimidazol‐2‐yl)phenol (HLMe) unit have been synthesized. They possess a N3O donor set that is known to stabilize phenoxyl radicals more efficiently than the corresponding N2O2 donor unit. Reaction of one molar equiv. of Cu(ClO4)2·6H2O with HLH or HLMe affords the zwitterionic benzimidazolium phenolate complexes [CuII(HLH)]2+ and [CuII(HLMe)]2+ via a proton transfer reaction coupled to copper(II) coordination. Addition of HClO4 to [CuII(HLH)]2+ and [CuII(HLMe)]2+ results in the formation of the benzimidazolium phenol complexes [CuII(H2LH)]3+ and [CuII(H2LMe)]2+, while addition of NEt3 affords the benzimidazol‐phenolate complexes [CuII(LH)]2+ and [CuII(LMe)]2+, respectively. The phenol’s pKa is remarkably low due to the strong withdrawing effect of the benzimidazolium substituent. X‐ray crystallographic analysis of the copper(II) complexes shows that deprotonation of the axial phenol forces the metal to move out of the square plane towards the oxygen atom, and one (or two) Cu–Npyridine equatorial bond length increases. The copper(II) phenoxyl species [CuII(HLH)]·3+ and [CuII(HLMe)]·3+ were prepared electrochemically, or by addition of two molar equiv. of copper(II) to HLH or HLMe. Under these conditions, radical formation has never been observed for tripodal ligands containing two pyridyl and one 2,4‐di‐tert‐butylphenol group. This difference is explained in terms of the proton transfer mechanism and redox potentials. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Ferrocenes Bearing Sulfinylamino Groups
Authors: Wrackmeyer Bernd , Klimkina Elena V. , Milius Wolfgang , Siebenbürger Miriam , Tok Oleg L. , Herberhold Max 
Published: August 2006

Abstract1,1′‐Diaminoferrocene (2) and 1,1′‐bis(trimethylsilylamino)ferrocene (3) have been converted into sulfinylamines by treatment with thionyl chloride in the presence of triethylamine. In the case of 2 the 1:2 reaction affords 1,1′‐bis(sulfinylamino)ferrocene (5) and the 1:1 reaction gives 6‐amino‐1‐sulfinylaminoferrocene (6). Bis(trimethylsilylamino)ferrocene reacts with thionyl chloride in a 1:1 molar ratio to give 1‐sulfinylamino‐6‐(trimethylsilylamino)ferrocene (8). In contrast, the reaction of N,N′‐dilithiobis(trimethylsilylamino)ferrocene (4) with thionyl chloride gives the [3]ferrocenophane 9, which contains an N–S(O)–N bridge, rather than sulfinylamines or a sulfur diimide. The molecular structures of 5 and 8 were determined by X‐ray analysis. The 57Fe NMR chemical shift (δ = +2597.0 ppm) for 5 indicates the strong π‐acceptor properties of the NSO groups. Dynamic 1H and 13C NMR spectra prove the hindered rotation of the NSO group about the C–N bonds in 5, 6 and 8. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
CoIII Complexes with Square‐Planar N2S2‐ and N2(SO2)2‐Type Ligands as An Active Site Structural Model for Nitrile Hydratase – Biological Implications of an Amidate Coordination
Authors: Yano Takuma , Arii Hidekazu , Yamaguchi Syuhei , Funahashi Yasuhiro , Jitsukawa Koichiro , Ozawa Tomohiro , Masuda Hideki 
Published: August 2006

AbstractIn an attempt to understand the unique active site structure of nitrile hydratase, four CoIII complexes with square‐planar N2S2‐ or N2(SO2)2‐type donor sets, Na[CoIII(L:N2S2)] (1‐Na), PPh4[CoIII(L:N2S2)] (1‐PPh4), PPh4[CoIII(L:N2S2)(tBuNC)2] (2), and PPh4[CoIII{L:N2(SO2)2}(tBuNC)2] (3) were synthesized and characterized on the basis of electronic absorption spectroscopy, IR spectroscopy, cyclic voltammetry, and X‐ray structural analysis. Both of the crystal structures of complexes 1‐Na and 1‐PPh4 revealed a square planar structure with N2S2 donating atoms, and 2 exhibited an octahedral structure coordinated with two tert‐butylisocyanide (tBuNC) molecules at the axial sites of complex 1‐PPh4. Complex 3, which showed an octahedral structure with sulfinate sulfur atoms equatorially coordinated to the center, was synthesized by the treatment of 2 with a suitable oxidant. The reduction potential values from CoIII to CoII for complex 3 in solution demonstrated a larger positive shift when compared with those of complexes 1‐PPh4 and 2, which indicates that the oxygenation of the sulfur atoms increased the Lewis acidity of the CoIII center. Interestingly, the coordination equilibrium, the C=O stretching frequency, and the redox potential for 1‐PPh4 were all closely related to the acceptor number (AN) of the solvents. Furthermore, the coordination of monodentate tBuNC to the axial position of 1‐PPh4 was dependent on the solvents used. These findings indicate that an electrophilic interaction between the carbonyl oxygen atoms and the solvent molecules control the Lewis acidity of the metal ion. On the other hand, such a solvent dependence was not detected in the S=O stretching frequency of sulfinates 3. We have concluded that the increase in the redox potential/Lewis acidity of the metal center is a result of the oxygenation of sulfur, and that this increase is controlled by the interaction of the amidate carbonyl oxygen with the secondary coordination sphere. As demonstrated in previous mutation studies, this study suggests that the interaction of the nitrile hydratase active site with the functional groups from the peptide backbone is essential for the catalytic activity of the complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Quantitative Removal of Mercury(II) from Water Through Bulk Liquid Membranes by Lipophilic Polyamines
Authors: Spreti Nicoletta , Brinchi Lucia , Germani Raimondo , Vincenza Mancini Maria , Savelli Gianfranco 
Published: August 2006

AbstractTransport of mercury(II) and copper(II) ions through bulk liquid membranes has been studied, the former because of its toxicity and wide distribution in the environment, the latter for comparative purposes. The abilities of two carriers, the known N,N′‐bis[2‐(hexadecylamino)ethyl]‐N,N′‐bis(hydroxyethyl)ethylenediamine (bis‐HE16ED) and the new N,N′‐bis(p‐octyloxybenzyl)‐3,6‐dioxaoctane‐1,8‐diamine (bis‐pODODA), to complex and transport the selected metal ions are reported. Bis‐HE16ED is a good carrier for Cu2+ ions, but the high stability of the carrier/Hg2+ ion complex in the membrane results in a lack of its transport. On the other hand, the new carrier displays a very high efficiency in Hg2+ ion transport, effecting quantitative transfer of the metal ion into the receiving phase within 24 h, despite its chelating region being only slightly different from that in bis‐HE16ED. The ability of bis‐pODODA to transport 100 % of Hg2+ efficiently in consecutive cycles is also reported. This result provides a basis for future development of a decontamination process based on a carrier‐mediated transport system. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Asymmetric Ring‐Opening of Epoxides and Aziridines with Carbon Nucleophiles
Authors: Pineschi Mauro 
Published: August 2006

AbstractThree‐membered heterocyclic rings offer a powerful combination of reactivity, stability, availability, and atom economy. While heteroatom‐based nucleophiles have been successfully employed, the use of carbon‐centered nucleophiles is much less developed, yet represents a significant advance since it builds the basic carbon framework. In fact, the asymmetric ring‐opening of epoxides and aziridines with carbon‐based nucleophiles, as will be discussed in this Microreview, offers the possibility of generating valuable, chiral, nonracemic building blocks in a very simple, stereodefined manner. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)