bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of peer collaboration on children's problem‐solving ability
Authors: Fawcett Lillian M. , Garton Alison F. 
Published: July 2005

Background.A Vygotskian framework links cognitive change to collaborative interaction with a more competent partner whereas a Piagetian perspective supports the view that cognitive conflict arising from peer interaction leads to cognitive change.Aims.The study investigated the effect of collaborative learning on children's problem‐solving ability and whether differences in knowledge status or the use of explanatory language were contributing factors.Sample.Participants were 100 Year 2 children (aged between 6 and 7 years), from schools in high socio‐economic areas, who individually completed a pre‐ and post‐test comprising a block sorting task.Method.During the experimental phase, children completed a card sorting activity, either individually or in same‐gender dyads. The dyads consisted of same or different ability children who operated under either a ‘talk’ or ‘no‐talk’ condition.Results.It was found that children who collaborated collectively obtained a significantly higher number of correct sorts than children who worked individually. However, post‐testing indicated that only those children of lower sorting ability who collaborated with higher sorting ability peers showed a significant improvement in sorting ability from pre‐test scores. In addition, it was found that when analysis was limited to this particular group, only those children who were required to explain the sort for their partner to carry out improved significantly from pre‐ to post‐test.Conclusion.It is suggested that perhaps the two theoretical positions are not as mutually exclusive as they are often portrayed. Implications of these findings for teachers and children's learning are also discussed.
Explaining individual differences in scholastic behaviour and achievement
Authors: Petrides K. V. , Chamorro‐Premuzic Tomas , Frederickson Norah , Furnham Adrian 
Published: July 2005

Background. This paper presents results from the first wave of a longitudinal study examining the effects of various psychosocial variables on scholastic achievement and behaviour at school.Aims. The main aim is to investigate the nature and strength of the effects of major individual difference dimensions on important outcome variables at school level, including academic performance, truancy, and antisocial behaviour.Samples. Data were collected from a sample of 901 pupils on verbal ability (as a proxy for cognitive ability), personality traits, and a number of behavioural indices, including academic performance at 14 and 16 years, number of authorized and unauthorized absences, and exclusions from school due to antisocial conduct.Methods. During the first stage of the study, seven schools participated in all three phases. Teachers administered a questionnaire battery in class according to a detailed protocol. Additional data were collected from school archives.Results. Analysis of the data through multi‐group (male and female puplis) structural equation modelling indicated a very strong effect of verbal ability on academic performance. Extraversion and psychoticism were negatively related to academic performance, although their effects were weak and moderated by gender. Verbal ability, extraversion, and psychoticism predicted absenteeism, truancy, and exclusions from school due to disruptive conduct. The latter three were negatively associated with academic performance.Conclusions. The findings indicate that major individual difference dimensions like verbal ability and personality traits, have a strong influence on important outcome variables at school level, including academic performance, truancy, and antisocial behaviour. Without fully acknowledging the crucial role of individual differences in shaping behaviour and achievement at school, the timely identification of pupils at risk, and the development of effective intervention schemes will be difficult.
Pupils' liking for school: Ability grouping, self‐concept and perceptions of teaching
Authors: Ireson Judith , Hallam Susan 
Published: July 2005

Background. Research indicates that affective aspects of development provide a basis for autonomous learning. Pupils' liking for school may be a useful indicator of their relationships with teachers and the school.Aims. The aim of the research reported in this paper is to establish the properties of a measure of pupils' liking for school and to examine associations between this measure, pupils' experiences in lessons, their self‐concepts and the amount of setting implemented in school.Sample. A stratified sample of 45 mixed secondary comprehensive schools was selected for the research. Schools represented a variety of ability‐grouping practices in the lower school (Years 7–9), from completely mixed‐ability to setting in all academic subjects. All Year 9 pupils were included in the sample.Methods. Pupils completed a questionnaire containing items on their self‐concept, liking for school, and their perceptions of teaching in English, mathematics, and science. Data on pupils' gender, ethnic origin, social disadvantage and attainment was also collected.Results and conclusions. The properties and correlates of scales indicating pupils' liking for school and their perceptions of teaching in English, mathematics, and science are established. Liking for school is greater among girls, pupils with higher academic self‐concepts, and those with more positive perceptions of teaching. Pupils are more positive about teaching they experience in English than in mathematics or science. When other variables are statistically controlled, there is no significant effect of the extent of ability grouping in the school as a whole. Affective aspects of learning should not be neglected in the drive to raise standards.
Reception class predictors of literacy skills
Authors: Simpson Jennifer , Everatt John 
Published: July 2005

Background. In the last decade, there has been a growing interest, both in the UK and abroad, in developing early screening tests for dyslexia that can be used with very young children. In addition to measures of literacy achievement, such screening tests typically aim to identify underlying difficulties, such as phonological deficits, that might hinder a child's educational progress. The Dyslexia Early Screening Test (DEST; Nicolson & Fawcett, 1996) is an example of such a test that combines attainment and diagnostic indicators.Aim. The study reported assessed the ability of the DEST to predict future literacy skills in contrast with the prediction afforded by school‐based measures, such as letter knowledge.Sample. Participants were 45 boys attending a reception class, with a mean age of 4.87 years at the start of the study and 6.63 years at the end.Methods. Measures of literacy skills, phonological awareness, verbal memory, motor skill, and auditory processing were assessed using the DEST as the initial screening tool at Phase 1. Measures of letter knowledge, non‐word reading, and rhyme judgment were taken at Phase 2. Phase 3 measures, 14 months after the start of the study, comprised single‐word reading and spelling. At Phase 4, some 22 months after the beginning of the study, measures of reading and spelling ability were assessed again.Results. Individual subtests of the DEST were more predictive of later literacy skills than the global screening test's score (the ‘at risk quotient’). Better predictors were the DEST subtest of sound order and rapid automatized naming, together with the school attainment measure of letter knowledge.Conclusions. Although some DEST subtests did offer predictors of future literacy skills, school‐based measures of letter knowledge may be equally valid as assessment measures. Additionally, the results question the usefulness of combining measures to form an ‘at risk’ index of future literacy difficulties, particularly in the age range assessed.
The social skills problems of victims of bullying: Self, peer and teacher perceptions
Authors: Fox Claire L. , Boulton Michael J. 
Published: July 2005

Background. A small number of prior studies have found that victims of school bullying tend to exhibit poor social skills. Few of these have examined this issue from multiple perspectives, and there has been a focus on a restricted range of social skills.Aims. To determine the extent to which self, peers, and teachers regard victims as having poorer social skills than non‐victims across 20 behaviours/competencies.Sample. A convenience sample of 330 pupils aged between 9 and 11 years (162 girls and 168 boys) provided self‐report and peer‐report data. They were drawn from 12 classes from 6 junior schools in the UK. Additionally, 11 of the class teachers provided data.Method. Three separate methods were employed and in each case, participants were provided with 20 short statements that described a different social skill: (1) participants who were classified as either ‘victims’ or ‘non‐victims’ (using peer nominations) rated themselves on a 3‐point scale in terms of how like them each description was, (2) participants were asked to think of a victim and a non‐victim in their class and to rate both of these people on each description, and (3) teachers were asked to rate a previously identified victim and a non‐victim from their class on each description.Results. Using a direct discriminant function analysis of the self‐ratings, six of the social skills items were found to discriminate between victims and non‐victims, and the discriminant function was able to correctly classify 80% of the participants. For 18 of the items, peer ratings indicated significantly more pronounced social skills problems for victims than for non‐victims. Teacher ratings were significant for eight of the social skill items, and in each case, victims were rated as having greater problems.Conclusion. The finding that victims are perceived by three different sources to have poor social skills has important implications for interventions to support victims of bullying.
NMR verification of single droplet freezing models
Authors: Hindmarsh J. P. , Wilson D. I. , Johns M. L. , Russell A. B. , Chen X. D. 
Published: July 2005

AbstractAcquiring temporal solid/liquid fraction data of a freezing system is advantageous for verifying theoretical solidification models. Nuclear magnetic resonance (NMR) spectrometry was used to obtain liquid fraction data of droplets of either water or sucrose solution undergoing freezing. The data obtained were used to verify numerical models of this solidification process. For water droplets, good agreement was observed between the experimental and model predictions of the temporal change in the water fraction over the range of air temperatures studied, whereas for the sucrose solution good agreement was observed only at the highest air temperature. At lower air temperatures, the discrepancies of the model were attributed to the possible crystallization of sucrose at temperatures above its reported glass‐transition temperature. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Thermal effects of CO2 absorption in aqueous solutions of 2‐amino‐2‐methyl‐1‐propanol
Authors: Camacho F. , Sánchez S. , Pacheco R. , Sánchez A. , La Rubia M. D. 
Published: July 2005

AbstractIn this work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 2‐amino‐2‐methyl‐1‐propanol (AMP), with respect to the thermal effects involved. The experiments were carried out in a stirred tank reactor with a plane and known interfacial area. The variables considered were the AMP concentration and the temperature, within the ranges 0.1–3.0 kmol/m3 and 288–313 K, respectively. From the results, we deduce that the absorption process of pure carbon dioxide into aqueous solutions of AMP takes place in the instantaneous nonisothermal regime at low concentrations, whereas at high concentrations the regime may be fast. In the experiments at low amine concentrations, we propose an equation, which not only relates the experimental results to the initial amine concentration but at the same time enables the evaluation of the rise in temperature in the gas–liquid interface. From the results at high concentrations, we determined a reaction order of one with respect to the amine and an expression for the kinetic constant valid throughout the entire range of temperatures and concentrations assayed: k = 4.8 × 1012exp(−8186.9/T). © 2005 American Institute of Chemical Engineers AIChE J, 2005
Synthesis of 6‐(3,5‐Dichlorobenzyl) Derivatives as Isosteric Analogues of the HIV Drug 6‐(3,5‐Dimethylbenzyl)‐1‐(ethoxymethyl)‐5‐isopropyluracil (GCA‐186)
Authors: Sørensen Esben R. , El‐Brollosy Nasser R. , Jørgensen Per T. , Pedersen Erik B. , Nielsen Claus 
Published: July 2005

AbstractThe HIV‐1 inhibitors described in this paper is closely related to 6‐(3,5‐dimethylbenzyl)‐1‐(ethoxy methyl)‐5‐isopropyluracil (GCA‐186) an anti‐HIV‐1 drug that is highly active against both wild type and mutated HIV‐1 strains. The two methyl groups on the 6‐benzyl moiety have been shown to improve the binding stability of the drug to the NNRTI‐binding site in reverse transcriptase of drug mediated mutant HIV‐1 viruses. The methyl groups are replaced with isosteric chloro‐atoms to avoid metabolism due to the two methyl groups. However, the isosteric chloro derivatives show tenfold less activity against HIV‐1 than their corresponding methyl derivatives. The synthesis and the antiviral activities of the corresponding 1‐(allyloxy‐ and indanyloxy)methyl‐6‐(3,5‐dichlorobenzyl)‐5‐ethyluracil derivatives are also reported.
Biopsy of resectable colorectal liver metastases causes tumour dissemination and adversely affects survival after liver resection
Authors: Jones O M , Rees M , John T G , Bygrave S , Plant G 
Published: July 2005

Abstract

Background
Liver resection is increasingly being performed for metastatic colorectal cancer. This study assessed the need for preoperative biopsy of suspected metastases and whether biopsy has any effect on long-term survival.

Methods
Prospectively collected data on patients who underwent liver resection for colorectal metastases between 1986 and 2003 were reviewed retrospectively. The endpoints of morbidity, operative mortality and long-term survival were compared between patients who had biopsy before referral (group 1) and those who did not (group 2).

Results
Patient demographics and disease distribution were similar for 90 patients in group 1 and 508 in group 2. Seventeen patients (19 per cent) who had undergone biopsy either at the time of colorectal resection or radiologically had evidence of needle-track deposits. Operative mortality and morbidity rates in the two groups were similar. The 4-year survival rate after liver resection was 32·5 (s.e. 5·5) per cent in group 1, compared with 46·7 (2·8) per cent in group 2 (P = 0·008).

Conclusion
Needle-track deposits are common after biopsy of suspected colorectal liver metastases. Biopsy of metastases confers poorer long-term survival on patients after liver resection and cannot be justified in patients with potentially resectable disease.
Adverse effects of radiofrequency ablation of liver tumours in the Netherlands
Authors: Jansen M C , van Duijnhoven F H , van Hillegersberg R , Rijken A , van Coevorden F , van der Sijp J , Prevoo W , van Gulik T M 
Published: July 2005

Abstract

Background
Radiofrequency ablation (RFA) is a new treatment for liver tumours. Complications encountered after RFA in the Netherlands were evaluated in the present study.

Methods
Between June 1999 and November 2003 patients undergoing RFA of irresectable liver tumours in eight medical centres were registered prospectively.

Results
One hundred and forty-three RFA procedures were performed in 122 patients. RFA was combined with partial hepatectomy in 37 instances. Death occurred after two procedures (1·4 per cent), and was mainly due to concomitant partial hepatectomy. A total of 19 major complications occurred after ten procedures, including biliary tract damage (seven patients), liver failure (four), hepatic abscess (three), peritoneal infection (two), intrahepatic haematoma (one), hepatic artery aneurysm (one) and pulmonary embolism (one). Twenty-four minor complications were related to concomitant partial hepatectomy or laparotomy. The overall complication rate was 20·3 per cent and the rate of complications related directly to RFA was 9·8 per cent.

Conclusion
The procedure-specific complication rate was almost 10 per cent and it is recommended that RFA should be performed only by an experienced team comprising a hepatobiliary surgeon, gastroenterologist, hepatologist and interventional radiologist. Biliary stricture, hepatic vascular damage and hepatic abscesses were the most common major complications.
Impaired IGF‐I signalling of hypertrophic hearts in the developmental phase of hypertension in genetically hypertensive rats
Authors: Kuo Wei‐Wen , Chu Chia‐Yih , Wu Chieh‐Hsi , Lin James A. , Liu Jer‐Yuh , Hsieh Yi‐Hsien , Ueng Kwo‐Chang , Lee Shin‐Da , Hsieh Dennis Jine‐Yuan , Hsu His‐Hsien , Chen Li‐Mien , Huang Chih‐Yang 
Published: July 2005

AbstractInsulin‐like growth factor‐I (IGF‐I) signalling is reported to contribute to the modulation of blood pressure and set survival and hypertrophic responses in cardiac tissue. However, whether IGF‐I signalling normally acts in cardiac tissues of hypertensive rats is unknown. In this study, using spontaneously hypertensive rats (SHR) and stroke‐prone spontaneously hypertensive rats (SPSHR), both with early blood pressure increases, and Wistar–Kyoto (WKY) rats as controls, we measured the hypertrophic and IGF‐I signalling activity changes in rat hearts at 4, 6 and 12 weeks of age. Both SHR and SPSHR were found to have significantly increased blood pressures and ratios of heart‐ and left ventricle‐ to body weight at 12 weeks of age. However, IGF‐IR and its downstream signalling, including the protein levels of PI3K and phosphorylated Akt, known to maintain physiological cardiac hypertrophy and cardiomyocyte survival, were downregulated. The results of dot blotting showed that cardiac mRNA levels of IGF‐I in hypertensive rats were higher than those in controls starting from the age of 4 weeks. This difference suggests the increased ligand IGF‐I mRNA levels may be a compensatory response caused by the impaired IGF‐I signalling. Moreover, enhanced cardiac cytosolic cytochrome‐c, a mitochondria‐dependent apoptotic pathway component, tended to occur in both hypertensive rats, although it did not reach a significant level. These findings indicate that impaired IGF‐IR signalling occurs at early stages, and it may contribute, at least partially, to the development of hypertension and pathological cardiac hypertrophy and to cardiomyocyte apoptosis at later stages in SHR and SPSHR. Copyright © 2005 John Wiley & Sons, Ltd.
Microchemical Engineering: Components, Plant Concepts User Acceptance – Part I
Authors: Hessel V. , Löwe H. 
Published: July 2005

AbstractOver the last five years, many activities have focused on the unexploited field of carrying out reactions on small scales. Due to the rapid development of new components, this paper deals with recent developments only in a compressed form. An important point is the analysis of possible plant concepts for microreactors and whether these are a sensible option. Due to the enormous difference in size between the microchannels and the fluid periphera of possible components this is not just a technical question. It touches on the microtechnology concept as a whole. The direction in which the field should be developed and which measures can be taken to influence its development are questions that are addressed here with respect to the big industrial interest in microreactors.
Partial least squares, Beer's law and the net analyte signal: statistical modeling and analysis
Authors: Nadler Boaz , Coifman Ronald R. 
Published: July 2005

AbstractPartial least squares (PLS) is one of the most common regression algorithms in chemistry, relating input–output samples (xi, yi) by a linear multivariate model. In this paper we analyze the PLS algorithm under a specific probabilistic model for the relation between x and y. Following Beer's law, we assume a linear mixture model in which each data sample (x, y) is a random realization from a joint probability distribution where x is the sum of k components multiplied by their respective characteristic responses, and each of these components is a random variable. We analyze PLS on this model under two idealized settings: one is the ideal case of noise‐free samples and the other is the case of an infinite number of noisy training samples. In the noise‐free case we prove that, as expected, the regression vector computed by PLS is, up to normalization, the net analyte signal. We prove that PLS computes this vector after at most k iterations, where k is the total number of components. In the case of an infinite training set corrupted by unstructured noise, we show that PLS computes a final regression vector which is not in general purely proportional to the net analyte signal vector, but has the important property of being optimal under a mean squared error of prediction criterion. This result can be viewed as an asymptotic optimality of PLS in the limit of a very large but finite training set. Copyright © 2005 John Wiley & Sons, Ltd.
Influence of HMPA on the Stereochemical Outcome of the Addition of a Racemic Allenylzinc onto Enantiopure N‐tert‐Butanesulfinimines: Stereoselective Access to Enantiopure cis‐Ethynylaziridines
Authors: Ferreira Franck , Audouin Max , Chemla Fabrice 
Published: July 2005

AbstractIn the presence of 60 equivalents of HMPA, the condensation of the racemic allenylzinc derived from 1‐chloro‐3‐trimethylsilylpropyne onto enantiopure non‐α‐branched N‐tert‐butanesulfinimines was proven to give access to the corresponding cis‐ethynylaziridines as the major products. The good cis selectivity observed presumably resulted from a high kinetic resolution with the allenylzinc being partially configurationally labile with respect to the time scale defined by the rate of the reaction. Both single crystal X‐ray analysis and semiempirical calculations conducted at the MM2 and AM1 levels of theory proved that the reaction certainly occurred through a preferred synclinal transition state in a supra‐ or antarafacial SE2′ process. In all cases, chromatographic purification over silica gel allowed the cis‐ethynyl‐N‐tert‐butanesulfinylaziridines to be obtained as diastereo‐ and enantiomerically pure compounds (dr >98:2 and ee >99 %).