bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intramolecular hydrogen bonding in derivatives of 3‐amino‐propenethial
Authors: Raissi H. , Jalbout A. F. , Fazli M. , Yoosefian M. , Ghiassi H. , Wang Z. , de Leon A. 
Published: February 2009

AbstractIntramolecular H‐bonds existing for derivatives of 3‐amino‐propenethial have been studied using the B3LYP/6‐311++G** level of theory. The nature of these interactions, known as resonance assisted hydrogen bonds, has been discussed. The topological properties of the electron density distributions for N—H—S intramolecular bridges have been analyzed in terms of the Bader theory of atoms in molecules. Correlations between the H‐bond strength and topological parameters have been also studied. Furthermore, we obtained the exact value of the intramolecular hydrogen bond energies by the related rotamers method. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Intramolecular hydrogen bonding in 3‐imino‐propenylamine: Theoretical investigations
Authors: Raissi H. , Jalbout A. F. , Farsi H. , Abbasi B. , de Leon A. , Moghiminia S. 
Published: February 2009

AbstractIntramolecular H‐bonds existing for derivatives of 3‐imino‐propenylamine have been studied using the B3LYP/6‐311++G** level of theory. The nature of these interactions, known as resonance‐assisted hydrogen bonds, has been discussed. Vibrational frequencies for α‐derivatives were calculated at the same level of theory. The topological properties of the electron density distributions for NH···N intramolecular bridges have been analyzed in terms of the Bader theory of atoms in molecules (AIM). Calculation for 3‐imino‐propenylamine derivatives in water solution were also carried out at B3LYP/6‐311++G** level of theory. Finally, the analysis of hydrogen bond in this molecule and their derivatives by quantum theory of natural bond orbital methods fairly support the ab initio results. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Hybrid density functional calculations of nuclear magnetic shieldings using Slater‐type orbitals and the zeroth‐order regular approximation
Authors: Krykunov Mykhaylo , Ziegler Tom , Lenthe Erik van 
Published: February 2009

AbstractWe report the implementation of an algorithm for the calculation of the exact Hartree–Fock exchange with Slater‐type orbitals (STOs). Similar to the article of Watson et al., J Chem Phys, 2003, 119, 6475, it is based on the fitting of each atomic orbital pair. However, our algorithm avoids the evaluation of three‐center two‐electron integrals and, as a result, makes it possible to carry out hybrid DFT calculations for larger size molecules and compounds with heavy elements. For the first time, the NMR chemical shifts of transition metal complexes have been calculated with STOs and hybrid density functionals. To take into account the relativistic effects, we have employed the zeroth‐order regular approximation. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
On variational estimates for exchange‐correlation interaction obtained within super‐CI approach to MCSCF approximation
Authors: Gusarov Sergey , Fedorova Tatiana A. , Dmitriev Yuri Yu. , Kovalenko Andriy 
Published: February 2009

AbstractVariation approximations for the exchange‐correlation interaction are considered which can be obtained when necessary conditions of the generalized Brillouin's theorem are fulfilled. It is done in the post‐Hartree–Fock approach to the electronic structure theories. The corresponding approximations appear within the two‐step Super‐CI self‐consistent procedure of the MCSCF one‐particle optimization. The basic formalism used is in close connection with the formalism of the extended Koopmans' theorem but here the extended Koopmans' matrix itself is calculated in a self‐consistent way. It is based on the singular value decomposition of the Koopmans' matrix. The final hermitian Koopmans' matrix satisfies the conditions of the generalized Brillouin's theorem. It commutes with the density matrix and equations for self‐consistent orbitals are transformed to the generalized Hartree–Fock equations with additional hermitian exchange correlation matrix. This matrix is interpreted as a matrix of the exchange‐correlation interaction. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
A model to predict the response of the benthic macroalga Spirogyra to reduced base flow in the tropical Australia
Authors: Townsend S. A. , Padovan A. V. 
Published: February 2009

AbstractA model was developed to predict the impact of reduced dry season base flow, due to groundwater and river extraction, on the standing crop of Spirogyra along an 18 km reach of the Daly River, located in the Australian wet/dry tropics. The alga can constitute up to 40% of the primary producer standing crop and is a food source for turtles. Outputs from a two‐dimensional hydrodynamic model and the observed maximum biomass of Spirogyra for a range of shear velocities were used to predict the maximum potential standing crop (MPSC) of Spirogyra. With reduced flow, hydraulic conditions became less favourable for the growth of Spirogyra, whilst the area of suitable substrata was not as responsive. The MPSC of Spirogyra was predicted for the minimum dry season flow for a 47 year period of hydrographic record using two hypothetical extraction scenarios. Both scenarios produced MPSCs that were frequently less than the minimum crop under natural flows and underscored the need for a minimum flow to maintain a MPSC that exceeded the historic minimum. The MPSC, however, is unlikely to be attained due to autogenic sloughing, nutrient supply and other factors, thus the model is best considered an index of the impact of reduced river flows. The model communicates a reduction in the standing crop of Spirogyra due to reduced dry season base flows and an inferred impact on its dependent fauna and the river's nutrient dynamics. The model demonstrates the utility of applying a benthic algal model to evaluate the ecological impact of modified flow regimes and contribute to environmental flow recommendations. Copyright © 2009 John Wiley & Sons, Ltd.
Phylogenomic Relationships of Rice Oxalate Oxidases to the Cupin Superfamily and Their Association with Disease Resistance QTL
Authors: Carrillo Maria Gay C. , Goodwin Paul H. , Leach Jan E. , Leung Hei , Vera Cruz Casiana M. 
Published: February 2009

Abstract
Rice oxalate oxidase genes (OXO) may play a role in resistance to Magnaporthe oryzae. Genome analyses showed four tandemly duplicated OXO genes, OsOXO1–OsOXO4, which mapped to a blast resistance QTL in chromosome 3. These genes have >90% nucleotide and amino acid identity, but they have unique gene structures, conserved motifs, and phylogeny compared to the 70 other members of the cupin superfamily in the Nipponbare genome, which were divided into several classes. In resistant and susceptible Vandana/Moroberekan advanced backcross lines, only OsOXO4 was expressed during rice–M. oryzae interactions, and its expression increased earlier in resistant than susceptible lines. The earlier expression of OsOXO4 in resistant lines correlated with a 26-bp promoter insertion containing an additional copy of the bacterial responsive nodulation cis-element. Our results showed that OsOXO1–4 are in a separate class of rice cupin genes and supports a role for the promoter variant of OsOXO4 in resistance to M. oryzae.
Cross‐cultural invariance of the Academic Expectations Stress Inventory: Adolescent samples from Canada and Singapore
Authors: Ang Rebecca P. , Klassen Robert M. , Chong Wan Har , Huan Vivien S. , Wong Isabella Y.F. , Yeo Lay See , Krawchuk Lindsey L. 
Published: February 2009

ABSTRACTWe provide further evidence for the two‐factor structure of the 9‐item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross‐cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross‐cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t‐tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross‐cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations.
Subgrouping low back pain: A comparison of the STarT Back Tool with the Örebro Musculoskeletal Pain Screening Questionnaire
Authors: Hill Jonathan C. , Dunn Kate M. , Main Chris J. , Hay Elaine M. 
Published: February 2009

AbstractIntroduction Clinicians require brief, practical tools to help identify low back pain (LBP) subgroups requiring early, targeted secondary prevention. The STarT Back Tool (SBT) was recently validated to subgroup LBP patients into early treatment pathways.Aim: To test the SBT's concurrent validity against an existing, popular LBP subgrouping tool, the Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ), and to compare the clinical characteristics of subgroups identified by each tool.Methods: Two hundred and forty‐four consecutive ‘non‐specific’ LBP consulters at 8 UK GP practices aged 18–59 years were invited to complete a questionnaire. Measures included the ÖMPSQ and SBT, disability, fear, catastrophising, pain intensity, episode duration and demographics. Instruments were compared using Spearman's correlations, tests for subgroup agreement and discriminant analysis of subgroup characteristics according to reference standards.Results: Completed SBT (9‐items) and ÖMPSQ (24‐items) data was available for 130/244 patients (53%). The correlation of SBT and ÖMPSQ scores was ‘excellent (rs = 0.80). Subgroup characteristics were similar across the low, medium and high subgroups, but, the proportions allocated to ‘low’, ‘medium’ and ‘high’ risk groups were different, with fewer patients in the SBT's high risk group. Both instruments similarly discriminated for reference standards such as disability, catastrophising, fear, comorbid pain and time off work. The ÖMPSQ was better at discriminating pain intensity, while the SBT was better for discriminating bothersomeness of back pain and referred leg pain.Conclusions: The SBT baseline psychometrics performed similarly to the ÖMPSQ, but the SBT is shorter and easier to score and is an appropriate alternative for identifying high risk LBP patients in primary care.
A 12-week lutein supplementation improves visual function in Chinese people with long-term computer display light exposure
Authors: Ma Le , Lin Xiao-Ming , Zou Zhi-Yong , Xu Xian-Rong , Li Ying , Xu Rui 
Published: February 2009

We aimed to examine the effect of different doses of lutein supplementation on visual function in subjects with long-term computer display light exposure. Thirty-seven healthy subjects with long-term computer display light exposure ranging in age from 22 to 30 years were randomly assigned to one of three groups: Group L6 (6 mg lutein/d, n 12); Group L12 (12 mg lutein/d, n 13); and Group Placebo (maltodextrin placebo, n 12). Levels of serum lutein and visual performance indices such as visual acuity, contrast sensitivity and glare sensitivity were measured at weeks 0 and 12. After 12-week lutein supplementation, serum lutein concentrations of Groups L6 and L12 increased from 0·356 (sd 0·117) to 0·607 (sd 0·176) μmol/l, and from 0·328 (sd 0·120) to 0·733 (sd 0·354) μmol/l, respectively. No statistical changes from baseline were observed in uncorrected visual acuity and best-spectacle corrected visual acuity, whereas there was a trend toward increase in visual acuity in Group L12. Contrast sensitivity in Groups L6 and L12 increased with supplementation, and statistical significance was reached at most visual angles of Group L12. No significant change was observed in glare sensitivity over time. Visual function in healthy subjects who received the lutein supplement improved, especially in contrast sensitivity, suggesting that a higher intake of lutein may have beneficial effects on the visual performance.
Writing dictated words and picture names: Syllabic boundaries affect execution in Spanish
Authors: ÁLVAREZ CARLOS J. , COTTRELL DAVID , AFONSO OLIVIA 
Published: February 2009

ABSTRACTTwo experiments examined the role of syllables in writing Spanish words. In Experiment 1, participants had to write single words that were aurally presented. The interletter intervals (ILIs) between critical letters were measured. Longer ILIs were found in the intersyllabic than the intrasyllabic condition. In Experiment 2, the inputs were pictures to remove any potential phonological bias stemming from the input stimulus. Results suggested that the linguistic nature of the input is not determining the output. Post hoc analyses revealed that other characteristics of the stimuli cannot explain the results. These results indicate that syllables are essential units of processing in writing Spanish and that central processes related to spelling and the graphemic buffer affect peripheral processes at movement execution.
A cross-linguistic and bilingual evaluation of the interdependence between lexical and grammatical domains
Authors: SIMON-CEREIJIDO GABRIELA , GUTIÉRREZ-CLELLEN VERA F. 
Published: February 2009

ABSTRACTThe purpose of this study was to examine within- and across-language relationships between lexical and grammatical domains by focusing on measures of lexical diversity and grammatical complexity in Spanish and English. One hundred ninety-six preschool and school-aged Latino children with different levels of English and Spanish proficiencies and different language abilities produced narratives in Spanish, English, or both. Analyses revealed strong associations between lexical (number of different words and number of different verbs) and grammatical measures (mean length of utterances in words and use of ditransitive predicates), supporting the domain interdependence hypothesis within a language. Cross-linguistic comparisons indicate a greater diversity of verbs and ditransitive predicates in Spanish compared to English for this population. In the language samples of children who produced narratives in the two languages, there was no relationship between the two domains across languages. The lack of cross-language correlations may be related to other variables influencing lexical and semantic development in bilingual learners. Methodological issues to be considered in future studies with bilingual speakers are discussed.
Food choices of the mountain gorilla in Bwindi Impenetrable National Park, Uganda: the influence of nutrients, phenolics and availability
Authors: Ganas Jessica , Ortmann Sylvia , Robbins Martha M. 
Published: February 2009

Abstract:The factors that influence food choice have implications for animal survival, reproduction and population growth. We conducted a 1-y study of food choice by four mountain gorilla groups that consumed herbs and fruit at two locations differing spatially and temporally in food availability in Bwindi Impenetrable National Park, Uganda. We collected data on 45 important foods consumed by the gorillas, the availability of those foods in each gorilla group's home range and their corresponding nutrient and phenolic concentrations. Employing a linear multiple regression, we tested three hypotheses regarding the influence of food availability and the nutritional and phenolic concentrations of food on food choice. Regardless of changes in herb availability, the choice of herbs was positively influenced by their abundance and sugar concentrations and negatively influenced by their fibre, condensed tannin and protein concentrations. Furthermore, regardless of changes in fruit availability, the choice of fruit was positively influenced by its abundance and negatively influenced by its condensed tannin concentrations. During periods of low fruit availability, the gorillas did not increase the consumption of herbs high in fibre and sugar. The choice of herbs low in fibre had less of an influence on food choice at the location with lower fruit availability than the other location. Our results underscore the importance of incorporating both availability and nutrient concentrations into studies of food choice; by doing so we found Bwindi gorillas were able to choose abundant, relatively high-quality foods year round.
Emerging temporality: past tense and temporal/aspectual markers in Spanish-speaking children's intra-conversational narratives
Authors: UCCELLI PAOLA 
Published: February 2009

ABSTRACTThis study describes how young Spanish-speaking children become gradually more adept at encoding temporality using grammar and discourse skills in intra-conversational narratives. The research involved parallel case studies of two Spanish-speaking children followed longitudinally from ages two to three. Type/token frequencies of verb tense, temporal/aspectual markers and narrative components were analyzed to explore interrelationships among grammatical and discourse skills. Children progressed from scattered unsystematic means of encoding temporality to mastering a basic linguistic system that included devices to mark location of events, temporal relations and aspectual meanings. The consolidation of perfective past tense to express narrative events marked a crucial developmental point which preceded an explosion of additional verb tenses and temporal markers. The value of spontaneous language data, and the need to study grammar and discourse simultaneously to construct a comprehensive developmental picture are highlighted. Results are discussed in relation to theoretical proposals on the development of temporality.
Grammaticality judgments in autism: Deviance or delay
Authors: EIGSTI INGE-MARIE , BENNETTO LOISA 
Published: February 2009

ABSTRACTLanguage in autism has been the subject of intense interest, because communication deficits are central to the disorder, and because autism serves as an arena for testing theories of language acquisition. High-functioning older children with autism are often considered to have intact grammatical abilities, despite pragmatic impairments. Given the heterogeneity in language skills at younger ages, this assumption merits further investigation. Participants with autism (n=21, aged nine to seventeen years), matched on chronological age, receptive vocabulary and IQ, to 22 typically developing individuals, completed a grammaticality judgment task. Participants with autism were significantly less sensitive than controls, specifically for third person singular and present progressive marking. Performance interacted with sentence length, with lower sensitivity to errors occurring at the end of the longest stimulus sentences. Performance sensitivity was associated with onset of single word and phrase speech, and with severity of autistic symptomatology. Implications of findings are discussed.
Informing surveillance programmes by investigating spatial dependency of subclinicalSalmonellainfection
Authors: BENSCHOP J. , STEVENSON M. A. , DAHL J. , MORRIS R. S. , FRENCH N. P. 
Published: February 2009

SUMMARYThe aim of this paper is to investigate local spatial dependency with regard toSalmonellaseropositivity in data from the Danish swine salmonellosis control programme and its application in informing surveillance strategies. We applied inhomogeneous and observed-differenceK-function estimation, and geo-statistical modelling to data from the Danish swine salmonellosis control programme. Slaughter-pig farm density showed large variation at both the country-wide and local level in Denmark (median 0·23, range 0·02–0·47 farms/km2). The spatial distribution of pig farms followed a random inhomogeneous Poisson process but was not aggregated. We found evidence for aggregation ofSalmonellacase farms over that of all farms at distances of up to 6 km and semivariogram analyses ofSalmonellaseropositivity revealed spatial dependency between pairs of farms up to 4 km apart. The strength of the spatial dependency was positively associated with slaughter-pig farm density. We proposed sampling more intensively those farms within a 4 km radius of farms that were identified with a highSalmonellastatus, and reduced sampling of farms that are within this radius of ‘Salmonella-free’ farms. Our approach has the potential to optimize sampling strategies while maintaining consumer confidence in food safety and also has potential to be used for other zoonotic disease surveillance systems.
Nest protectors provide a cost-effective means of increasing breeding success in Giant Ibis Thaumatibis gigantea
Authors: KEO OMALISS , COLLAR NIGEL J. , SUTHERLAND WILLIAM J. 
Published: February 2009

SummaryA main cause of nestling loss of the ‘Critically Endangered’ Giant Ibis Thaumatibis gigantea appeared to be mammalian predation. Predator-exclusion devices were added to a randomly selected half of 52 nesting trees, with the other half acting as controls. The number of young fledged per nest was 50% higher for protected nests than control nests. Each protected nest produced almost two-thirds (0.63) of an extra chick. During the nestling period, the daily nestling survival rate was (99.9%) (equivalent to 90% survival over the nestling period) for protected nests and 99.3% (61.3% survival over the whole period) for control nests. Nest protection devices cost US$5 per tree. Each extra nestling fledged as a result of this intervention therefore cost $8. If it was also necessary to pay to locate the nests, then the cost of protecting each nest would be $140 and the cost of producing each extra chick $224. Trees with protectors added were significantly more likely to be reused in the next year than unprotected trees.