bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing narrative comprehension in young children
Authors: PARIS ALISON H. , PARIS SCOTT G.
Published: June 2004

ABSTRACTS

This article explains the creation and validation of the Narrative Comprehension of Picture Books task (NC task), an assessment of young children's comprehension of wordless picture books. Study 1 explored developmental changes among 158 K‐2 children in narrative comprehension and the correlations among children's performance on the NC task and other measures of early reading. There was significant improvement with increasing age on NC task measures. Significant concurrent validity was found between the NC task and oral reading comprehension for readers and between the NC task and several prereading skills for prereaders. Study 2 tested the generalizability of the NC task by giving a sub‐sample of students (n= 91) two additional picture books using the NC task procedures. Intertask correlations showed that children were consistent on each of the NC task dependent variables across the three books. The same developmental trends by grade and reading ability were evident on all three versions of the task. Study 3 confirmed the generalizability of the NC task across children, books, and testers, and it revealed sensitivity to longitudinal growth in children's comprehension skills. There was little evidence of practice effects influencing NC scores. Study 3 also revealed significant concurrent and predictive validity between NC measures and other assessments of early reading skills such as the Gates McGinitie Reading Test and the Iowa Test of Basic Skills. The NC task is a valid quantitative measure of young children's comprehension that is sensitive to developmental changes and adaptable to various books. We discuss how narrative comprehension is fundamental to beginning reading and how the NC task may be used for classroom instruction and assessment.
Language proficiency and reading ability in first‐ and second‐language learners
Authors: DROOP MIENKE , VERHOEVEN LUDO
Published: June 2004

ABSTRACTS

The purpose of the present study was to investigate the development of and interrelations between the language proficiencies and reading abilities of children learning to read in either a first language or a second language. The authors compared the reading‐comprehension, word‐decoding, and oral‐language skills of both high and low SES Dutch third and fourth graders to the skills of low SES minority third and fourth graders from a Turkish or Moroccan background living in the Netherlands. Several tests of reading comprehension, word decoding, oral text comprehension, morphosyntactic knowledge, and vocabulary knowledge were administered at the beginning of third grade, the end of third grade, and the end of fourth grade. The results showed the minority children to be faster decoders than the Dutch low SES children. With respect to reading comprehension and oral language proficiency, however, the minority children were found to lag behind the Dutch children in all respects. With respect to the interrelations between oral‐language skills and reading skills, the development of reading comprehension was found to be influenced more by top‐down comprehension‐based processes than by bottom‐up word‐decoding processes for both the first‐ and second‐language learners. The oral Dutch skills of the minority children played a more prominent role in the explanation of their reading‐comprehension skills than the oral‐language skills of the Dutch children, however.
Critical policy analysis: Researching the roles of cultural models, power, and expertise in reading policy
Authors: WOODSIDE‐JIRON HAYLEY
Published: June 2004

Book reviewed in this article:

America Reads: A Critical Policy Analysis. Jacqueline Edmondson. 2000.

Misreading Reading: The Bad Science That Hurts Children. Gerald Coles. 2000.
Achieving the goal of a quality teacher of reading for every classroom: Divest, test, or invest?
Authors: HOFFMAN JAMES V.
Published: June 2004

Book reviewed in this article:

Learning to Teach Reading: Setting the Research Agenda. Edited by Cathy Roller. 2001.

Meeting the Highly Qualified Teachers Challenge: The Secretary's Annual Report on Teacher Quality. 2002. U.S. Department of Education, Office of Postsecondary Education, Office of Policy Planning and Innovation.

No Dream Denied: A Pledge to America's School Children. 2003. National Commission on Teaching and America's Future.

Quality Counts 2003: “If I Can't Learn From You….” 2003. Education Week.

Teacher Certification Reconsidered: Stumbling for Quality. 2001. The Abell Foundation.
Gender effects in spatial orientation: cognitive profiles and mental strategies
Authors: Bosco Andrea , Longoni Anna M. , Vecchi Tomaso
Published: June 2004

Experimental evidence and meta‐analyses offer some support for gender‐related differences in visuo‐spatial ability. However, few studies addressed this issue in an ecological context and/or in everyday tasks implying spatial abilities, such as geographical orientation. Moreover, the relation of specific strategies and gender is still unclear. In the present investigation, we compared men and women in a newly designed battery of spatial orientation tasks in which landmark, route and survey knowledge were considered. In addition, four visuo‐spatial working memory (VSWM) tasks were presented. Significant differences favouring men in VSWM tasks were reported, supporting existing evidence. However, men and women did not significantly differ in orientation tasks performance. The patterns of correlation between working memory and spatial orientation tasks indicated that men and women used somewhat different strategies in carrying out the orientation tasks. In particular, active processes seem to play a greater role in females' performance, thus confirming the importance of this variable in interpreting gender effect in VSWM tasks. Altogether, results indicate that gender effects could well result from differences in cognitive strategies and support data indicating that adequate training could reduce or eliminate them. Copyright © 2004 John Wiley & Sons, Ltd.
Interviewing young children with props: prior experience matters
Authors: Nigro Georgia N. , Wolpow Sarah I.
Published: June 2004

This study investigated the effects of prior experience with props used during an interview on young children's recall of an event. In a one‐way design, we interviewed 4‐year‐old children 1 to 2 days after they participated in a staged event. One group of children played with toy replicas of items from the event prior to an interview with the toy props. Another group matched toy replicas to real items from the event prior to an interview with the toy props. A third group coloured before an interview with the toy props, and a fourth coloured before an interview with the real items. Finally, a fifth group coloured before an interview with no props, only verbal cues about the items that had been present. Results indicated that the condition in which children played with toy props prior to the interview had the lowest verbal accuracy during the interview. Children who saw toys for the first time during the interview behaviourally enacted the highest volume of correct information about the event. Implications for interviewing children are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Memory distortions in coerced false confessions: a source monitoring framework analysis
Authors: Henkel Linda A. , Coffman Kimberly J.
Published: June 2004

Confessions are routinely offered as evidence and are potentially damning to defendants. However, not all confessions are truthful. Suspects can be coerced into falsely confessing to crimes that they did not commit, and in a subset of cases, the confessors come to genuinely believe they committed the crimes and sometimes create vivid ‘memories’ of their activities. Against the backdrop of a model of cognitive processes involved in correct and incorrect remembering known as the source monitoring framework, this paper examines how coercive tactics routinely used in interrogations may give rise to memory illusions and distortions that can contribute to false confessions in which individuals believe they are guilty and create false memories to support those beliefs. Copyright © 2004 John Wiley & Sons, Ltd.
Feigning amnesia undermines memory for a mock crime
Authors: Oorsouw Kim Van , Merckelbach Harald
Published: June 2004

Using scripts, previous studies by Christianson and co‐workers have suggested that simulating amnesia undermines memory. Relying on a more realistic mock crime paradigm, the current study examined whether feigning amnesia has memory‐undermining effects. After committing a mock crime, one group of participants (n = 21) was instructed to simulate amnesia for the event. Their performance on immediate free recall tests was compared to that of participants (n = 20) who were instructed to respond honestly during free recall. After one week, simulators, honestly responding controls, and a second control group (n = 20) that had not undergone immediate memory testing after the pertinent event completed free recall tests. This time, all participants were instructed to perform as well as they could.

At the follow‐up free recall test, both ex‐simulators and controls who underwent the memory testing for the first time performed significantly worse than the honestly responding controls. Thus, the current study supports the idea that simulating amnesia in order to evade responsibility for a crime has detrimental effects on true memory of the crime. Our results also suggest that this effect can best be understood in terms of lack of rehearsal. Copyright © 2004 John Wiley & Sons, Ltd.
Assumptions: Taking Chemistry in New Directions
Authors: Whitesides George M.
Published: June 2004

Is thinking about the future an important thing to do or just a diversion? Science periodically requires society to discard important assumptions, with profound consequences. Failed assumptions are easy to identify with hindsight, but can they be predicted? In this Essay, the author discusses assumptions society accepts, and the potential of science to disprove them.
Functional analysis and treatment of low rate problem behavior in individuals with developmental disabilities
Authors: Tarbox Jonathan , Wallace Michele D. , Tarbox Rachel S. F. , Landaburu Heidi J. , Williams W. Larry
Published: June 2004

Extensive research has validated the standard functional analysis as a useful technology for identifying the function of problem behavior in individuals with developmental disabilities. The assessment of low rate problem behavior is one area that has yet to receive a significant amount of research. Some problem behaviors may occur at rates too low to be observed during a standard functional analysis, despite the fact that they may be highly destructive behaviors. The current study evaluated the effectiveness of initiating functional analysis sessions contingent on the occurrence of bursts of problem behavior for producing interpretable functional analysis results. While a standard functional analysis did not produce definitive results with respect to behavioral function, the ‘low rate’ functional analysis produced interpretable results for all three participants. Two of the three participants were available for the evaluation of treatments based on their functional analysis results. Function‐based treatments suppressed rates of problem behavior for both participants. Copyright © 2004 John Wiley & Sons, Ltd.
Modifications to basic functional analysis procedures in school settings: a selective review
Authors: Ellis Janet , Magee Sandy
Published: June 2004

This review describes applied behavioral research involving functional analyses conducted in public school settings. Functional analyses in public school settings often require added conditions. The modified conditions described herein include changes to experimental designs, antecedent changes that include task variation, tasks included, idiosyncratic variables, physiological conditions, and modified escape conditions. Finally, consequent modifications cover peer attention, tangibles, varied attention, and altered escape. Copyright © 2004 John Wiley & Sons, Ltd.
A further comparison of external control and problem‐solving interventions to teach social skills to adults with intellectual disabilities
Authors: O'Reilly Mark F. , Lancioni Giulio E. , Sigafoos Jeff , Green Vanessa A. , Ma Chia‐Hui , O'Donoghue Deirdre
Published: June 2004

We compared the effectiveness of a problem‐solving and an external control intervention to teach social skills to two adults with mild intellectual disabilities. Each participant received the problem‐solving intervention with one social skill and the external control intervention with another social skill. The comparative effectiveness of the social skill training protocols was evaluated using individual participant alternating treatment designs. Overall, there seemed to be little difference between the interventions in terms of acquisition, generalization, or maintenance of social skills with either participant. Limitations of the current study and issues for future research are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
The neurodevelopmental outcome in infants who have sustained a subdural haemorrhage from non‐accidental head injury
Authors: Karandikar Swati , Coles Lisa , Jayawant Sandeep , Kemp Alison M.
Published: June 2004

Subdural haemorrhage (SDH) in infants arises most commonly from non‐accidental head injury (NAHI) from shaking. Patients present with a varied severity of illness and a variety of symptoms and signs. Data on long‐term outcome of the survivors are not widely reported. The aim of this paper is to describe the physical and educational outcomes of children <2 years diagnosed with non‐accidental head injury and formulate guidelines on follow‐up. Data on 65 children <2 years with non‐accidental head injury and subdural haemorrhage diagnosed on CT/MRI/postmortem were extracted from the hospital and community notes and education reports. The Kings Outcome Scale for Childhood Head Injury (KOSCHI) was used. Sixteen children died (24.6%), 13 within 6 weeks and three 5 years after the injury. Of the 45 children followed up (follow‐up time 21.7–103 months), 25 had a good outcome, six were moderately disabled and 11 were severely disabled, while three were in persistent vegetative state. Problems identiﬁed included cerebral palsy—16, ongoing seizures—5, visual problems—11, speech and language problems—17 and behavioural problems—13. Of the 29 children of school age on whom data were available, 12 children had a statement of educational needs. In conclusion, young children who survive non‐accidental head injury can have signiﬁcant physical, cognitive and behavioural problems. Regular follow‐up by a multidisciplinary team, which includes a community paediatrician, therapists, school health personnel and ophthalmologic services, until the child is established in school may facilitate early identiﬁcation of emerging problems and optimize management. Care must be taken not to discharge children with good outcomes, as behavioural and cognitive problems can emerge with time. Only a prospective study will help outline the subtle problems that can emerge with time in children with a so‐called good outcome. Copyright © 2004 John Wiley & Sons, Ltd.
Structure Determination of an Organometallic 1‐(Diazenylaryl)ethanol: A Novel Toxin Subclass from the Web of the Spider Nephila clavipes
Authors: Marques Maurício Ribeiro , Mendes Maria Anita , Tormena Cláudio Francisco , Souza Bibiana M. , Ribeiro Susan P. , Rittner Roberto , Palma Mario S.
Published: June 2004

A novel chemical subclass of toxin, [1‐(3‐diazenylphenyl)ethanol]iron, was identified among the compounds present in the web of the spider Nephila clavipes. This type of compound is not common among natural products, mainly in spider‐venom toxins; it was shown to be a potent paralytic and/or lethal toxin applied by the spider over its web to ensure prey capture only by topical application. The structure was elucidated by means of ESI mass spectrometry, 1H‐NMR spectroscopy, high‐resolution (HR) mass spectrometry, and ICP spectrometry. The structure of [1‐(3‐diazenylphenyl)ethanol]iron and the study of its insecticidal action may be used as a starting point for the development of new drugs for pest control in agriculture.
Copper(II) Complexes Containing N,N‐Donor Ligands and Dipeptides Act as Hydrolytic DNA‐Cleavage Agents
Authors: Reddy Pulimamidi R. , Rao Kandibanda S. , Mohan Sepuru K.
Published: June 2004

Copper(II) complexes are known to play a significant role in both naturally occurring biological systems and pharmaceutical agents. Recently, CuII complexes have gained importance in DNA cleavage essential for the development of anticancer drugs and chemotherapeutic agents. Therefore, we have designed small molecules, consisting of a metal ion, N,N‐donor ligands, and dipeptides, to probe their DNA‐cleaving potential. Accordingly, the interaction of CuII with ethylenediamine, histamine and the dipeptides histidylglycine, histidylalanine, and histidylleucine has been investigated. The binding modes, stabilities, and geometries of these complexes were determined by various physicochemical techniques. Their DNA‐binding abilities were probed by absorption and fluorescence spectroscopy, and their DNA‐cleavage potential was tested by electrophoresis.
Enantiospecific Syntheses of C(5)‐Functionalized Precursors of Artemisinin Derivatives
Authors: Cravero Raquel M. , Labadie Guillermo R. , Sierra Manuel Gonzalez , Mc Chesney James D.
Published: June 2004

Enantiomerically pure compounds as precursors for the synthesis of hydroxylated derivatives of artemisinin/arteether have been prepared from (+)‐(S)‐carvone and (+)‐car‐2‐ene.
Synthesis, Spectral Properties, and Antitumor Activity of a New Axially Substituted Phthalocyanine Complex of Zirconium(IV) with Citric Acid
Authors: Tomachynski Larisa A. , Chernii Victor Y. , Gorbenko Helena N. , Filonenko Valeriy V. , Volkov Sergey V.
Published: June 2004

The new axially substituted phthalocyanine (pc) complex of zirconium(IV) with citric acid is reported. It has been shown that the replacement of two Cl‐atoms with two citric acid fragments takes place as the result of the reaction between [ZrCl2(pc)] and citric acid. The complex [Zr(citrate)2(pc)] was formed. The spectroscopic properties of the synthesized compound in DMSO, RPMI 1640 medium with and without fetal calf serum (FCS), H2O, and buffer (Tris) solutions have been described. Antitumor activity of this compound has been studied. The cytostatic activity was observed in the concentration range of 6.1–9.0×109 molecules [Zr(citrate)2(pc)]/cell and occurred in 4–6 h after treatment with [Zr(citrate)2(pc)] solution.
Cancer Chemopreventive Activity of Serratane‐Type Triterpenoids from Picea jezoensis
Authors: Tanaka Reiko , Minami Toshifumi , Ishikawa Yohei , Tokuda Harukuni , Matsunaga Shunyo
Published: June 2004

To search for cancer chemopreventive agents from natural sources, 13α,14α‐epoxy‐21α‐methoxyserratan‐3‐one, 21α‐methoxyserrat‐13‐en‐3‐one, and 21α‐hydroxy‐3β‐methoxyserrat‐14‐en‐30‐al isolated from the cuticle of Picea jezoensis (Sieb. et Zucc.) Carr. var. jezoensis (Pinaceae) were investigated for inhibitory effects in a two‐stage mouse skin carcinogenesis test on mouse skin with 7,12‐dimethylbenz[a]anthracene (DMBA) as initiator and 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) as promoter. 21α‐hydroxy‐3β‐methoxyserrat‐14‐en‐30‐al and 13α,14α‐epoxy‐21α‐methoxyserratan‐3‐one were found to exhibit strong antitumor‐promoting activities in the in vivo carcinogenesis test.
DNA Minor‐Groove Recognition by 3‐Methylthiophene/Pyrrole Pair
Authors: Doss Raymond M. , Marques Michael A. , Foister Shane , Dervan Peter B.
Published: June 2004

Hairpin polyamides are synthetic oligomers, which fold and bind to specific DNA sequences in a programmable manner. Internal side‐by‐side pairings of the aromatic amino acid residues 1‐methyl‐1H‐pyrrole (Py), 1‐methyl‐1H‐imidazole (Im), and 3‐hydroxy‐1‐methyl‐1H‐pyrrole (Hp) confer the ability to distinguish between all four WatsonCrick base pairs in the minor groove of B‐form DNA. In a broad search to expand the heterocycle repertoire, we found that when 3‐methylthiophene (Tn), which presents a S‐atom to the minor groove, is paired with Py, it exhibits a modest threefold specificity for T⋅A>A⋅T presumably by shape‐selective recognition. In this study, we explore the scope and limitations of this lead by incorporating multiple Tn residues within a single hairpin polyamide. It was found that hairpin polyamides containing more that one Tn/Py pair exhibit lowered affinities and specificities for their match sites. It appears that little deviation is permissible from the parent five‐membered ring 1‐methyl‐1H‐pyrrole‐2‐carboxamide scaffold for DNA recognition.
Enzymatic Baeyer–Villiger Oxidation as the Key Step in Decano‐4‐lactone and Decano‐5‐lactone Degradation by Sporobolomyces odorus
Authors: Garbe Leif‐A. , Tressl Roland
Published: June 2004

The biosyntheses of aroma active γ‐ and δ‐lactones have been previously characterized in yeasts and plants by incubation of labeled fatty acid derivatives. The lactones were considered as end products. Liquid cultures of the lactone‐producing yeast Sporobolomyces odorus were used to investigate catabolic pathways of the lactones by incubation of ethyl (±)‐5‐hydroxy(1‐13C1)decanoate ((13C)‐1b) and methyl (±)‐4‐hydroxy(1‐13C1)decanoate ((13C)‐7a). Aliquots of the culture broth were analyzed with GC/MS after CH2N2 derivatization. S. odorus degraded (13C)‐1b to 5‐oxo(1‐13C1)decanoic acid ((13C)‐2c) and, subsequently, to pentyl (1‐13C1)pentanedioate ((13C)‐3c) and 3‐[(1‐13C1)carboxypropyl] hexanoate ((13C)‐4c) by a BaeyerVilliger‐type oxidation (BVO). In addition, the oxidation of (13C)‐7a to 4‐oxo(1‐13C1)decanoic acid ((13C)‐8c) and a BVO of (13C)‐8c to hexyl (1‐13C1)butanedioate ((13C)‐9c) is reported. So far, BVO has been observed in bacteria and some fungi; the data presented indicate a BVO catalyzed by the yeast S. odorus in the course of endogenous lactone metabolism.
Wedge‐Shaped Molecules with a Sulfonate Group at the Tip—A New Class of Self‐Assembling Amphiphiles
Authors: Zhu Xiaomin , Tartsch Bernd , Beginn Uwe , Möller Martin
Published: June 2004

The synthesis of 4‐N‐[3′,4′,5′‐tris(dodecyloxy)benzamido]benzene‐4‐sulfonic acid (1) and 4′‐[3′′,4′′,5′′‐tris(dodecyloxy)benzoyloxy]azobenzene‐4‐sulfonic acid (2) is described. Pure acid 1 is stable, while 2 can be stored only in solution. Both acids were obtained from their sodium salts and were quantitatively transformed into the pyridinium salts. The phase behavior of these acids, as well as the sulfonates was investigated by differential scanning calorimetry and polarizing optical microscopy. The investigated compounds exhibit columnar mesophases. The formation of columnar superstructures was demonstrated for the sodium sulfonates by scanning force microscopy, gelation experiments, and proton magnetic resonance spectroscopy.
Copper‐Free Monomeric and Dendritic Palladium Catalysts for the Sonogashira Reaction: Substituent Effects, Synthetic Applications, and the Recovery and Re‐Use of the Catalysts
Authors: Heuzé Karine , Méry Denise , Gauss Dominique , Blais Jean‐Claude , Astruc Didier
Published: June 2004

A series of bis(tert‐butylphosphine)‐ and bis(cyclohexylphosphine)‐functionalized PdII monomers and polyamino (DAB) dendritic catalysts were synthesized and investigated for Sonogashira carbon–carbon coupling reactions in a copper‐free procedure. The influence of phosphine substituents (tBu versus Cy) on the reaction kinetics was investigated by a GPC technique to monitor the reactions. The dendritic catalysts containing the cyclohexylphosphine ligands could be recovered and reused without loss of efficiency until the fifth cycle. The dendritic PdII catalysts show a negative dendritic effect, that is, the catalyst efficiency decreases as the dendrimer generation increases.
Solvation of Uranyl(II), Europium(III) and Europium(II) Cations in “Basic” Room‐Temperature Ionic Liquids: A Theoretical Study
Authors: Chaumont Alain , Wipff Georges
Published: June 2004

We report a molecular dynamics study of the solvation of UO22+, Eu3+ and Eu2+ ions in two “basic” (Lewis acidity) room‐temperature ionic liquids (IL) composed of the 1‐ethyl‐3‐methylimidazolium cation (EMI+) and a mixture of AlCl4− and Cl− anions, in which the Cl−/AlCl4− ratio is about 1 and 3, respectively. The study reveals the importance of the [UO2Cl4]2− species, which spontaneously form during most simulations, and that the first solvation shell of europium is filled with Cl− and AlCl4− ions embedded in a cationic EMI+ shell. The stability of the [UO2Cl4]2− and [EuIIICl6]3− complexes is supported by quantum mechanical calculations, according to which the uranyl and europium cations intrinsically prefer Cl− to the AlCl4− ion. In the gas phase, however, [EuIIICl6]3− and [EuIICl6]4− complexes are predicted to be metastable and to lose two to three Cl− ions. This contrasts with the results of simulations of complexes in ILs, in which the “solvation” of the europium complexes increases with the number of coordinated chlorides, leading to an equilibrium between different chloro species. The behavior of the hydrated [Eu(OH2)8]3+ complex is considered in the basic liquids; the complex exchanges H2O molecules with Cl− ions to form mixed [EuCl3(OH2)4] and [EuCl4(OH2)3]− complexes. The results of the simulations allow us to better understand the microscopic nature and solvation of lanthanide and actinide complexes in “basic” ionic liquids.
Interstitial Zn Atoms Do the Trick in Thermoelectric Zinc Antimonide, Zn4Sb3: A Combined Maximum Entropy Method X‐ray Electron Density and Ab Initio Electronic Structure Study
Authors: Cargnoni Fausto , Nishibori Eiji , Rabiller Philippe , Bertini Luca , Snyder G. Jeffrey , Christensen Mogens , Gatti Carlo , Iversen Bo Brummerstadt
Published: June 2004

The experimental electron density of the high‐performance thermoelectric material Zn4Sb3has been determined by maximum entropy (MEM) analysis of short‐wavelength synchrotron powder diffraction data. These data are found to be more accurate than conventional single‐crystal data due to the reduction of common systematic errors, such as absorption, extinction and anomalous scattering. Analysis of the MEM electron density directly reveals interstitial Zn atoms and a partially occupied main Zn site. Two types of Sb atoms are observed: a free spherical ion (Sb3−) and Sb24−dimers. Analysis of the MEM electron density also reveals possible Sb disorder along thecaxis. The disorder, defects and vacancies are all features that contribute to the drastic reduction of the thermal conductivity of the material. Topological analysis of the thermally smeared MEM density has been carried out. Starting with the X‐ray structure ab initio computational methods have been used to deconvolute structural information from the space‐time data averaging inherent to the XRD experiment. The analysis reveals how interstitial Zn atoms and vacancies affect the electronic structure and transport properties of β‐Zn4Sb3. The structure consists of an ideal A12Sb10framework in which point defects are distributed. We propose that the material is a 0.184:0.420:0.396 mixture of A12Sb10, A11BCSb10and A10BCDSb10cells, in which A, B, C and D are the four Zn sites in the X‐ray structure. Given the similar density of states (DOS) of the A12Sb10, A11BCSb10and A10BCDSb10cells, one may electronically model the defective stoichiometry of the real system either by n‐doping the 12‐Zn atom cell or by p‐doping the two 13‐Zn atom cells. This leads to similar calculated Seebeck coefficients for the A12Sb10, A11BCSb10and A10BCDSb10cells (115.0, 123.0 and 110.3 μV K−1atT=670 K). The model system is therefore a p‐doped semiconductor as found experimentally. The effect is dramatic if these cells are doped differently with respect to the experimental electron count. Thus, 0.33 extra electrons supplied to either kind of cell would increase the Seebeck coefficient to about 260 μV K−1. Additional electrons would also lowerσ, so the resulting effect on the thermoelectric figure of merit of Zn4Sb3challenges further experimental work.
Cover Picture: Organic Spin Clusters: Annelated Macrocyclic Polyarylmethyl Polyradicals and a Polymer with Very High Spin S=6–18 (Chem. Eur. J. 13/2004)
Authors: Rajca Andrzej , Wongsriratanakul Jirawat , Rajca Suchada , Cerny Ronald L.
Published: June 2004

The cover picture shows structures of organic spin clusters, based upon Gomberg's triarylmethyl compounds. The clusters are related to the first conjugated polymer with magnetic ordering. For more details see the article by A. Rajca et al. on p. 3144 ff.
Dueling experts in mediation and negotiation: How to respond when eager expensive entrenched expert egos escalate enmity
Authors: Wade John H.
Published: June 2004

Having dueling experts is a predictable problem for negotiators and mediators. A routine process in response is set out: normalizing, reframing, and turning the barrier into a standard problem‐solving question. Twelve standard responses (each with inevitable advantages and disadvantages) are systematized for mediators and negotiators to learn and possibly add value to any negotiation.
Traditional mediation practices: Are we throwing the baby out with the bath water?
Authors: Chia Ho‐Beng , Lee‐Partridge Joo Eng , Chong Chee‐Leong
Published: June 2004

This article examines the mediation practices of the Chinese and Malay communities in Singapore and highlights the role of cultural and community values, beliefs, and religion in shaping the mediation process. A comparison of traditional Chinese, Malay, and newly institutionalized practices shows the differences in approaches and the role of “neutral” community members in the mediation process.
Conflict, peace, and education: A tangled web
Authors: Tidwell Alan
Published: June 2004

In this article the author examines peace education in zones of conflict. Central to his thesis is that peace education, though returning valuable service to a conflict‐affected community, must take into account the local conflict conditions. It is important to understand the range of ways in which conflict can affect provision of education; many of these ways are identified.
Civil conflict, education, and the work of schools: Twelve propositions
Authors: Williams James H.
Published: June 2004

Education and civil conflict are deeply intertwined in complex ways. The author posits a series of hypotheses about interrelationships by which schools are a natural arena for conflict—attracting violence, sometimes helping to prevent it, and fostering it as well. Violence affects schools at multiple levels; attacking individuals, communities, and systems, and weakening their sense of agency.
In their own words: Contextualizing the discourse of (war) trauma and healing
Authors: Fuertes Al B.
Published: June 2004

This article highlights community‐based conceptions and articulations of warviews and coping mechanisms among refugees in a camp along the Thailand‐Burma border. The author asserts that, no matter how victimized they may feel about themselves, the refugees are capable of naming and responding to their collective sense of reality and can be active participants in their own healing and community building.
Bridging theory and practice in peace education: The Notre Dame University peace education experience
Authors: Bacani Benedicto R.
Published: June 2004

Amidst a raging war in Central Mindanao and the historical biases and prejudices between Muslims and Christians, peace education as a curricular offering, pioneered by Notre Dame University, seeks to educate students to be more open and tolerant of diversity and to promote active nonviolence as an effective means for positive change.
Assessment of volume of fluid and immersed boundary methods for droplet computations
Authors: Lörstad Daniel , Francois Marianne , Shyy Wei , Fuchs Laszlo
Published: June 2004

The volume of fluid (VOF) and immersed boundary (IB) methods are two popular computational techniques for multi‐fluid dynamics. To help shed light on the performance of both techniques, we present accuracy assessment, which includes interfacial geometry, detailed and global fluid flow characteristics, and computational robustness. The investigation includes the simulations of a droplet under static equilibrium as a limiting test case and a droplet rising due to gravity for Re⩽1000. Surface tension force models are key issues in both VOF and IB and alternative treatments are examined resulting in improved solution accuracy. A refined curvature model for VOF is also presented. With the newly developed interfacial treatments incorporated, both IB and VOF perform comparably well for the droplet dynamics under different flow parameters and fluid properties. Copyright © 2004 John Wiley & Sons, Ltd.
Expanding the Genetic Alphabet: Pyrazine Nucleosides That Support a DonorDonorAcceptor Hydrogen‐Bonding Pattern
Authors: von Krosigk Ulrike , Benner Steven A.
Published: June 2004

The 6‐aminopyrazin‐2(1H)‐one, when incorporated as a pyrimidine‐base analog into an oligonucleotide chain, presents a H‐bond donordonoracceptor pattern to a complementary DNA or RNA strand. When paired with the corresponding acceptoracceptordonor purine in oligonucleotides, the heterocycle selectively contributes to the stability of the duplex, presumably by forming a base pair of WatsonCrick geometry joined by a nonstandard H‐bonding pattern, expanding the genetic alphabet. Reported here is a short, high yielding, β‐D‐selective synthesis of a 6‐aminopyrazin‐2(1H)‐one nucleoside via the glycine riboside derivative 28. The key steps include a WittigHorner reaction of an appropriately protected ribose derivative (Scheme 10, 19→21) followed by a Michael‐like ring closure (Scheme 12, 30→1a and 32→1b). Thus, a variety of pyrazine nucleosides (Scheme 13) including the target 6‐aminopyrazin‐2(1H)‐one riboside 1a, and its 5‐methyl derivative 1b, 6‐amino‐5‐methylpyrazin‐2(1H)‐one riboside, are obtained.
Oligo(triacetylene) Derivatives with Pendant Long Alkyl Chains
Authors: Nierengarten Jean‐François
Published: June 2004

Substituted (E)‐2‐(ethynyl)but‐2‐ene and (E)‐hex‐3‐ene‐1,5‐diyne derivatives 6 and 10, respectively, were prepared by dicyclohexylcarbodiimide(DCC)‐mediated esterification of tris(dodecyloxy)benzoic acid (4) with (E)‐2‐[(triisopropylsilyl)ethynyl]but‐2‐ene‐1,4‐diol (3) and (E)‐2,3‐bis[(trimethylsilyl)ethynyl]but‐2‐ene‐1,4‐diol (8), respectively, followed by deprotection with Bu4NF in wet THF (Schemes 1 and 2). Oligomerization reactions of diyne derivative 10 were attempted by treatment with the Hay catalyst in the presence of mono‐alkyne 6 as an end‐capping reagent. Under these conditions, only compound 7 resulting from the homocoupling of 6 (Scheme 1), and polymers of 10 were obtained due to the difference in reactivity of the alkyne groups in 6 and 10. In contrast, when phenylacetylene was used as the stopper, the oligomerization of 10 afforded a mixture of end‐capped oligomers, from which 11–13 were isolated by column chromatography (Scheme 3). The poly(triacetylenes) (PTA) 16–18 were prepared in a similar manner starting from diol 8 and stearic acid (Schemes 4 and 5). Whereas the end‐capped monomers and dimers 11, 12, 16, and 17 with pendant long alkyl chains do not exhibit any liquid‐crystalline behavior, the trimeric derivatives 13 and 18 show mesomorphic properties, thus demonstrating that the poly(triacetylene) backbone can behave as a mesogenic unit.
Annosqualine: a Novel Alkaloid from the Stems of Annona squamosa
Authors: Yang Yu‐Liang , Chang Fang‐Rong , Wu Yang‐Chang
Published: June 2004

Annosqualine (=(10′bR)‐1′,5′,6′,10′b‐tetrahydro‐9′‐hydroxy‐7′,8′‐dimethoxyspiro[cyclohexa‐2,5‐diene‐1,2′‐pyrrolo[2,1‐a]isoquinoline]‐3′,4‐dione; 1), a novel alkaloid with an unprecedented skeleton, and a new amide, dihydrosinapoyltyramine (=3‐(4‐hydroxy‐3,5‐dimethoxyphenyl)‐N‐[2‐(4‐hydroxyphenyl)ethyl]propanamide; 2), were isolated from the stems of Annona squamosa L., together with six known alkaloids. The structures of all compounds were elucidated spectroscopically by means of optical rotation, 1H‐, 13C‐, and 2D‐NMR, and by EI‐MS, or by comparison with the spectral data of authentic samples. A possible biogenetical pathway towards annosqualine (1) is proposed.
Studies under Continuous Irradiation of Photochromic Spiro[fluorenopyran‐thioxanthenes]
Authors: Salvador Maria A. , Coelho Paulo J. , Burrows Hugh D. , Oliveira M. Manuel , Carvalho Luis M.
Published: June 2004

New indeno‐fused spiro[benzopyran‐thioxanthenes] were synthesized (see 3a–d in Scheme 3) and their photochromic properties evaluated under continuous irradiation (Table 1). When submitted to irradiation for several minutes with a Xe lamp, the system behaved as one constituted by two open colored forms with different thermal bleaching rates and different susceptibilities to degradation. An increase in irradiation time led to significant degradation and to the apparent predominance of the open colored form with the faster bleaching rate.
Cyclic Seven‐Membered Ketene Imines from Hindered ‘Thiocarbonyl Ylides’ and 2,3‐Bis(trifluoromethyl)fumaronitrile: Properties and Surprising Reactions
Authors: Huisgen Rolf , Langhals Elke , Polborn Kurt , Karaghiosoff Konstantin
Published: June 2004

‘Thiocarbonyl ylide’ 2B is accessible from 1,1,3,3‐tetramethylindanthione and CH2N2, and subsequent N2 extrusion at 40–50°. In situ cycloaddition of the sterically hindered 2B with 2,3‐bis(trifluoromethyl)fumaronitrile ((E)‐3) affords the isolable spirocyclic ketene imine 4B in high yield. X‐Ray analysis discloses angle deformation, with ring strain being responsible for the high reactivity of 4B. In CDCl3 at 40°, 4B isomerizes to the trans‐spirothiolane 6B and fragments to 1,2‐bis(trifluoromethyl)cyclopropane‐1,2‐dicarbonitrile (12) (+thioketone 11B) in parallel reactions with a ratio of ca. 4:1. Van der Waals strain limits the thermal stability of 6B, which, at 60° in CDCl3, is slowly converted to 11B and 12. Kinetics studies are in accordance with the zwitterionic intermediate 5B in gauche and anti conformations. In CD3CN, 4B enters into a third parallel reaction, which leads to a formal adduct with CD3CN. X‐Ray analysis reveals the amidine 13; this deep‐seated, unexpected structural change is rationalized with the assumption of a nine‐membered cyclic intermediate. In CD3CN at 80°, 13 and 12 (+11B) are stable and occur in a ratio of ca. 1 : 1. Hindered ‘thiocarbonyl ylides’ 2C and 2D produce, in reactions with (E)‐3 or (Z)‐3, the cyclic ketene imines 4C and 4D, respectively, which likewise isomerize to trans‐thiolanes 6C and 6D. In contrast to 6B and 6C, the less‐hindered thiolane 6D is thermostable and does not fragment; it undergoes trans⇌cis equilibration in PhCN at 139°. Structural assignments of thiolanes are based on 19F‐NMR spectroscopy.
Eudesmane‐Type Sesquiterpene Derivatives from Saussurea conica
Authors: Fan Cheng‐Qi , Zhan Zha‐Jun , Li Hui , Yue Jian‐Min
Published: June 2004

Four new eudesmane‐type sesquiterpene derivatives, 3β‐[(β‐D‐glucopyranosyl)oxy]‐11αH‐eudesm‐4(14)‐en‐12,8β‐olide (1), (3β)‐eudesma‐4(14),11(13)‐diene‐3,12‐diol (2), 3β‐[(β‐D‐glucopyranosyl)oxy]eudesma‐4(14),11(13)‐dien‐12‐ol (3), and 3β‐[(β‐D‐glucopyranosyl)oxy]eudesm‐4(14)‐en‐11‐ol (4), together with the known (3β)‐eudesm‐4(14)‐ene‐3,11‐diol (5) were isolated from Saussurea conica, and their structures were elucidated both spectroscopically and by chemical methods.
FN+Cl Ions from Ionized F2NCl: a Computational Investigation on the Structure and Reactivity toward H2O
Authors: Borocci Stefano , Bronzolino Nicoletta , Grandinetti Felice
Published: June 2004

We have used various ab initio methods and basis sets to ascertain that the FN+Cl cation has a singlet ground state, 1A′, which is more stable than the triplet state 3A″ by ca. 30 kcal mol−1. We have subsequently used the Gaussian‐3 (G3) theory to explore the potential‐energy profile for the reaction between singlet FN+Cl and H2O. The process commences by the effortless formation of a FN+Cl/H2O complex, which, in principle, can undergo several alternative processes, including isomerization to N‐protonated FN(Cl)OH, 1,2‐elimination of HX (X=F or Cl), and 1,1‐loss of H2. However, the energy barriers of all these processes are invariably larger than the energy (+18.1 kcal mol−1) required for the formation of FN+Cl/H2O from FN+Cl and H2O, thus suggesting that, under gas‐phase thermal conditions, FN+Cl should be essentially unreactive toward H2O. Comparing these theoretical findings with those concerning the reaction between FN+H, ClN+H, F2N+, and H2O, the reactivity order FN+H>F2N+>ClN+H>FN+Cl, was derived, which parallels the trend we recently found by G2MS calculations concerning the Lewis acidity of these ions. This suggests the conceivable occurrence of correlations between the reactivity and thermochemical properties of these simple halonitrenium ions.
Effective High‐Pressure Cleavage of Sterically Hindered Steroid Esters
Authors: Kroszczyński Wojciech , Olszewska Ewa , Sałański Piotr , Jurczak Janusz
Published: June 2004

A simple and effective method to deprotect of sterically hindered steroid esters is described. Deprotection was carried out in MeOH in the presence of a catalytic amount of Et3N under high‐pressure conditions. Enzymatic, anionite, and high‐pressure methods are compared.
Acetylene Sorption Dynamics in Carbon Nanotubes
Authors: Onyestyák György , Ötvös Zsolt , Valyon József , Kiricsi Imre , Rees Lovat V. C.
Published: June 2004

Single‐walled and multi‐walled carbon nanotubes (SWNT and MWNT, resp.) were prepared by applying the catalytic chemical vapor deposition (CCVD) technique. Different nanotube samples were obtained from the as‐synthesized carbon/catalyst composites by treatments applied to remove the catalyst and the amorphous carbon. The dynamic and equilibrium adsorption properties of the samples were compared. Acetylene was used as an adsorptive probe. The sorption mass‐transport properties have been characterized by applying the frequency response (FR) technique. Results reflected that the surface functional groups, generated by an oxidative treatment, have significant influence on both the static and the dynamic acetylene sorption properties of the carbon nanotube materials. The rate of acetylene mass transport was governed by the rate of sorption in all the samples, except in MWNT after oxidative treatment, where the intracrystalline diffusion in the nanotubes was the rate‐controlling process.
DFT Calculations Indicate that 1,4‐Dihydropyridine Is a Promising Lead Antioxidant
Authors: Wang Lan‐Fen , Zhang Hong‐Yu , Kong Ling , Chen Zhi‐Wei , Shi Jian‐Guo
Published: June 2004

By density‐functional‐theory (DFT) calculations, 1,4‐dihydropyridine (1) was found to be a powerful lead antioxidant with high H‐atom‐donating ability and relatively low pro‐oxidant activity. Moreover, two ethoxycarbonyl (EtOCO) substituents at C(2) and C(6) should further enhance its H‐atom‐donating ability due to resonance effects.
Transition‐Metal‐Based Lewis Acid Catalysis of Aza‐Type Michael Additions of Amines to α,β‐Unsaturated Electrophiles in Water
Authors: Xu Li‐Wen , Li Lyi , Xia Chun‐Gu
Published: June 2004

Several transition‐metal‐based Lewis acid catalysts, especially FeCl3⋅7 H2O, CrCl3⋅6 H2O, and SnCl4⋅4 H2O, were shown to be highly effective for aza‐type Michael reactions between electrophilic α,β‐unsaturated compounds and both aliphatic and aromatic amines in aqueous solution. Advantages of the new protocol include 1) high‐yielding reactions that can be conducted at ambient temperature; 2) the use of inexpensive, stable transition‐metal salts as catalysts; and 3) plain H2O as an environmentally benign solvent.
Crystal Structure of 3,4,5,6‐Tetrahydrophthalic Anhydride at 150 K
Authors: Fredj Arij Ben , Bagieu‐Beucher Muriel , Rejeb Sadok Ben , Lakhdar Zohra Ben
Published: June 2004

The crystal structure of 3,4,5,6‐tetrahydrophthalic anhydride, (=4,5,6,7‐tetrahydroisobenzofuran‐1,3‐dione; 1; C8H8O3) was determined and refined by an analysis of three‐dimensional X‐ray‐diffraction data at 150 K. This bicyclic compound crystallizes in space group Pbca with two symmetry‐independent molecules I and II per asymmetric unit. The cyclohexene ring in both molecules adopts a half‐chair conformation. The obtained conformational descriptions of the six‐membered rings in the crystal phase are consistent with conformational data derived from molecular‐orbital calculations. The structure analysis evidences considerable distorsion of the partially hydrogenated six‐membered ring; the furan ring is flattened in molecule I and slightly deviated from planarity in molecule II. The short intermolecular distances found for CO⋅⋅⋅CO are interpreted as evidence for nonbonded interactions of the dipole–dipole type. The rather long O⋅⋅⋅H distances indicate that the C(sp3)‐H⋅⋅⋅O interactions are weak.
Nine Triterpene Dimers from Maytenus chuchuhuasca
Authors: Shirota Osamu , Sekita Setsuko , Satake Motoyoshi , Morita Hiroshi , Takeya Koichi , Itokawa Hideji
Published: June 2004

Nine regioisomeric and stereoisomeric triterpene dimers, named xuxuarine Hα (1), xuxuarine Hβ (2), xuxuarine Iα (3), xuxuarine Iβ (4), isoxuxuarine Hα (5), 7,8‐dihydroisoxuxuarine Hα (6), 7,8‐dihydroisoxuxuarine Iα (7), xuxuarine Jα (8), and xuxuarine Kα (9), were isolated from the Brazilian medicinal plant ‘xuxuá’ (Maytenus chuchuhuasca Raymond‐Hamet et Colas). Their structures were elucidated on the basis of several spectroscopic analyses including 2D‐NMR experiments, mass spectra, and circular dichroism (CD) studies.
Properties and Reactions of Substituted 1,2‐Thiazetidine 1,1‐Dioxides: Functionalization and Reactions at C(4) of the β‐Sultam
Authors: Plagge Herbert , Manicone Nico , Otto Hans‐Hartwig
Published: June 2004

The introduction of functional groups at the 4‐position of the β‐sultam ring was realized by the synthesis of mono‐ and disubstituted derivatives by reactions of N‐silylated β‐sultams with electrophiles in the presence of BuLi or LDA. As electrophiles, ketones, chlorosilanes, a β‐sultam, CO2, chloroformiate, halogen, azodicarboxylate, phenyltriazoledione, tosyl azide, 1,3,5‐triazine, propyl nitrate, and phenyl isocyanate were used. Furthermore, a number of derivatives of these substitution products were synthesized. All products were characterized by standard spectroscopic methods, and conformations were studied, supported by calculation.
Five New Quassinoids from the Bark of Picrasma quassioides
Authors: Yang Sheng‐Ping , Yue Jian‐Min
Published: June 2004

Five new quassinoids, named picraqualides A–E (1–5), together with eleven known ones, nigakilactone E (6), nigakilactone F (7), kusulactone (8), javanicin U (9), 12‐norquassin (10), quassin (11), 2,3‐didehydropicrasin B (12), nigakilactone B (13), nigakilactone C (14), picrasin B (15), and simalikalacton C (16), were isolated from the EtOH extract of the bark of Picrasma quassioides (D. Don) Benn. Their structures were determined mainly by spectroscopic methods, especially by 2D‐NMR techniques and circular dichroism (CD). Some empirical rules were summarized on the basis of 13C‐NMR spectral analysis to distinguish between OH (or Ac) groups attached at C(11) vs. C(13).