bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative analysis of polymeric proanthocyanidins in birch leaves with normal‐phase HPLC
Authors: Karonen Maarit , Ossipov Vladimir , Sinkkonen Jari , Loponen Jyrki , Haukioja Erkki , Pihlaja Kalevi 
Published: April 2006

AbstractThe proanthocyanidin composition and content in the leaves of nine birch species (Betula albosinensis, B. ermanii, B. maximowicziana, B. nana, B. papyrifera, B. pendula, B. platyphylla, B. pubescens, and B. pubescens ssp. czerepanovii) were studied with different methods including colorimetric assay, HPLC coupled with PAD or ESI/MS and NMR. Total proanthocyanidin content was determined using the acid butanol assay. A normal phase‐HPLC method was applied for the analysis of polymeric proanthocyanidins. The content of polymeric proanthocyanidins was estimated from a late eluting peak in the chromatogram. With this HPLC method, quantitative analysis of polymeric proanthocyanidins could be performed directly from leaf extracts: no additional purification or preparation steps were required. It was shown that birch leaves contained mainly polymeric proanthocyanidins with a degree of polymerisation greater than 10. Total proanthocyanidin content (expressed as dry weight) was found to vary from 44 mg/g (B. papyrifera) to 145 mg/g (B. nana), and polymeric proanthocyanidin content from 39 mg/g (B. pendula) to 119 mg/g (B. nana). Copyright © 2006 John Wiley & Sons, Ltd.
On Different Approaches to Estimate the Mass Fractal Dimension of Coal Aggregates
Authors: Liao Jimmy Y. H. , Selomulya Cordelia , Bushell Graeme , Bickert Götz , Amal Rose 
Published: April 2006

AbstractSeveral methods to measure the structures of coal aggregates are compared. Loose and compact coal aggregates were generated through flocculation of ultrafine coal particles (mean volume diameter of 12 μm) under specific shearing conditions. Aggregate structure in terms of mass fractal dimension, Df, was determined using various methods; namely 2D and 3D image analysis, interpretation of intensity patterns from small angle light scattering, changes in aggregation state through light obscuration, and settling behavior. In this study, the measured values of Df ranged from 1.84–2.19 for coal aggregates with more open structures, and around 2.27–2.66 for the compact ones. All of these approaches could distinguish structural differences between aggregates, albeit with variation in Df values estimated by the different techniques. The discrepancy in the absolute values for fractal dimension is due to the different physical properties measured by each approach, depending on the assumptions used to infer Df from measurable parameters. In addition, image analysis and settling techniques are based on the examination of individual aggregates, such that a large number of data points are required to yield statistically representative estimations. Light scattering and obscuration measure the aggregates collectively to give average Df values of the particulate systems; consequently ignoring any structural variation between the aggregates, and leaving possible small contaminations undetected (e.g. by dust particles or air bubbles). Appropriate utilization of a particular method is thus largely determined by system properties and required data quality.
Extrapolation methods for improving convergence of spherical Bessel integrals for the two‐center Coulomb integrals
Authors: Safouhi Hassan , Bouferguene Ahmed 
Published: April 2006

AbstractMulti‐center two‐electron Coulomb integrals over Slater‐type functions are required for any accurate molecular electronic structure calculations. These integrals, which are numerous, are to be evaluated rapidly and accurately. Slater‐type functions are expressed in terms of the so‐called B functions, which are best suited to apply the Fourier transform method. The Fourier transform method allowed analytic expressions for these integrals to be developed. Unfortunately, the analytic expressions obtained turned out to be extremely difficult to evaluate accurately due to the presence of highly oscillatory spherical Bessel integrals. In this work, we used techniques based on nonlinear transformation and extrapolation methods for improving convergence of these oscillatory spherical Bessel integrals. These techniques, which led to highly efficient and rapid algorithms for the numerical evaluation of three‐ and four‐center two‐electron Coulomb and exchange integrals, are now shown to be applicable to the two‐center two‐electron Coulomb integrals. The numerical results obtained for the molecular integrals under consideration illustrate the efficiency of the algorithm described in the present work compared with algorithms using the epsilon (ε) algorithm of Wynn and Levin's u transform. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Genetic and environmental sources of egg size, fecundity and body size in the migrant skipper, Parnara guttata guttata (Lepidoptera: Hesperiidae)
Authors: Seko Tomokazu , Miyatake Takahisa , Fujioka Shinsuke , Nakasuji Fusao 
Published: April 2006

AbstractGenetic and environmental sources of egg size, fecundity and body size (forewing length) were examined in the butterfly, Parnara guttata guttata. Phenotypic and genetic correlation and heritability were estimated for these traits under different day‐length and temperature conditions. Egg size and fecundity had relatively high heritabilities, and body sizes in males and females had moderate and high heritability, respectively. Negative phenotypic and genetic correlations between egg size and fecundity were estimated in treatments corresponding to the natural conditions during larval development of the first and second generations. Phenotypic and genetic correlations between body size and egg size differed considerably between insects reared under long and short day‐lengths. Next, genotype–environment interactions were estimated by comparing reaction norms to day‐length or temperature of these traits among families. ANOVA analysis revealed significant genotype–environment interactions in egg size and forewing length in both sexes for day‐length and temperature. These results suggested that a large additive genetic variance for egg size might have been maintained by a genetic trade‐off and/or by genotype–environment interactions in P. g. guttata.
U/Th age constraints on the absence of ice in the central Inn Valley (eastern Alps, Austria) during Marine Isotope Stages 5c to 5a
Authors: Spötl Christoph , Mangini Augusto 
Published: April 2006

AbstractCalcitic flowstones are present in fractures of a Pleistocene breccia near Innsbruck, Austria, and record periods of carbonate precipitation in the unsaturated zone between 101,500 ± 1500 and 70,300 ± 1800 yr, constrained by U-series disequilibrium dates. The occurrence of these speleothems, their low carbon isotopic composition, and the lack of infiltrated siliciclastic material demonstrate that the central Inn valley – which harbored one of the most extensive valley glaciers during the last glacial maximum – was ice-free during Marine Isotope Stages 5c to 5a. Climatically warm periods are separated by distinct drops in the oxygen isotopic composition of the speleothem calcite, attributed to strong and possibly seasonally biased atmospheric cooling. During these intervening stadials, which mirror those identified in the Greenland ice cores and marine sea-surface temperature records, calcite deposition apparently came to a halt, but the Inn Valley remained ice-free. The youngest calcite layer formed between ∼74,000 and ∼70,000 yr and places a maximum age limit on the likely expansion of alpine glaciers during the Marine Isotope Stage 5/4 transition, consistent with other speleothem records.
Fetal and perinatal risk factors for inflammatory bowel disease
Authors: Aspberg Sara , Dahlquist Gisela , Kahan Thomas , Källén Bengt 
Published: April 2006

Abstract Aim: To study the influence of specific factors and events during pregnancy and the perinatal period on the risk of children developing inflammatory bowel disease. Methods: Population‐based national register study. Linkage between the Swedish Medical Birth Register and the Swedish Hospital Discharge Register during the period 1987 to 2000 identified 455 singleton infants who later developed inflammatory bowel disease. Data for these children were compared with data for all children born in Sweden during the same period. Results: Smoking during early pregnancy reduced the risk of inflammatory bowel disease (odds ratio (OR) 0.71, 95% CI 0.55–0.91). For ulcerative colitis the odds ratio was 0.70 (95% CI 0.56–0.86), and for Crohn's disease 0.73 (95% CI 0.58–0.94). Infections during the neonatal period seemed to increase the risk of inflammatory bowel disease (OR 17.6, 95% CI 3.6–51.6), but the number of observed events was small. The other factors examined did not influence the risk of inflammatory bowel disease.Conclusion: Maternal smoking during early pregnancy reduces the risk for the child to be hospitalized with a diagnosis of inflammatory bowel disease. Severe neonatal infections may increase the risk. Thus, some exposures during the fetal and neonatal period seem to affect the risk of inflammatory bowel disease later in life.
Physical outcome and school performance of very‐low‐birthweight infants treated with minimal handling and early nasal CPAP
Authors: Dahl Marianne , Kamper Jens 
Published: April 2006

Abstract Aim: To describe physical outcome and school performance in a cohort of very‐low‐birthweight infants treated with early nasal continuous positive airway pressure (NCPAP)/minimal handling regimen with permissive hypercapnia, in comparison to siblings of normal birthweight. Material and methods: Neonatal and follow‐up data from 213 very‐low‐birthweight infants from 1983–1988 were registered and a questionnaire concerning school achievements was sent to the families of survivors and siblings attending school. Results: Mortality was 22%. Of the survivors, 4% had moderate–severe and 9% mild sequelae. Eighty‐seven per cent of VLBW children and 95% of their siblings attended regular school. Average or above‐average achievement was accomplished by 33 (65%) of the VLBW children and 34 (74%) of the siblings in mathematics, and 35 (69%) and 32 (68%), respectively, in reading/spelling. None of these differences reached statistical significance. However, the performance ratings correlated significantly with socio‐economic conditions. Conclusion: In this study of infants treated with a regimen of early NCPAP/minimal handling, we found a relatively low incidence of handicaps and impairments. Nearly 90% attended ordinary schools, with near‐average performances in mathematics and reading/spelling, which were not statistically different to their siblings. The overall results indicate that these infants fare at least as well as survivors after conventional treatment.
Glucose intolerance and insulin resistance in extremely premature newborns, and implications for nutritional management
Authors: YEUNG MELINDA Y. 
Published: April 2006

AbstractGlucose intolerance and postnatal growth retardation are commonly seen in low‐gestation newborns. In contrast to the nutrient compositions of parenteral and enteral nutrition, fetuses at equivalent gestational ages receive much more amino acids (protein) but less glucose and lipids through placental transfer. Conclusion: A nutrition regime that simulates placental nutrient delivery would potentially minimize glucose intolerance and facilitate early attainment of normal growth velocity with normal body composition after preterm birth.
Sensory and affective components of pain as recorded with the Pain‐O‐Meter (POM) among children with acute and chronic pain
Authors: Jylli Leena , Broström Eva , Hagelberg Stefan , Stenström Christina H. , Olsson Gunnar L. , Langius‐Eklöf Ann 
Published: April 2006

Abstract Aim: To explore the usefulness of the Pain‐O‐Meter sensory and affective words scale (POM‐WDS) with regard to whether children aged 6–16 who suffer from chronic and acute pain know the words and what words they chose to describe their pain. Methods: Sixty‐one children participated, mean age 11 y, suffering from acute pain (n=25) and pain associated with juvenile idiopathic arthritis (JIA, n=36). Children rated their pain intensity on the POM‐VAS (visual analogue scale, 0–10 cm). Thereafter, children were asked whether each sensory and affective word on the POM‐WDS was known to them, and whether each word described their pain experience. Results: Seventeen out of 23 words were known to at least 70% of the sample. The least recognized word was grinding. Children age 6–16 knew fewer words than the adolescents. Age was a significant determinant for whether the children knew the words grinding (odds ratio (OR) 20.08, p<0.01), gnawing (OR 5.92, p < 0.05), unbearable (OR 8.02, p<0.05), and excruciating (OR 20.17, p<0.001). Terrible (OR 33.3, p<0.05), aching (OR 44.5, p<0.05) and sore (OR 5.4, p<0.05) were selected more often by children with acute pain than with JIA. Conclusion: Further studies will be required to determine the suitability of using the POM‐WDS with children.
Difficult intubation of a child through laryngeal mask airway with two tracheal tubes
Authors: KENDIIRLI TANIL , INCE ERDAL , KAVAZ ASLI , ÇIFTÇI ERGIN , ALANOĞLU ZEKERIYA , DOĞRU ÜLKER 
Published: April 2006

AbstractDifficult tracheal intubation occurs infrequently. It is estimated that difficult laryngoscopy occurs in 1–2% of patients. Tracheal intubation of especially small infants can be challenging. When faced with a difficult airway, intubation through a laryngeal mask airway is one method of obtaining a secure airway. Here, we report a 23‐mo‐old girl with chronic lung disease and severe pneumonia, who was admitted to our paediatric intensive care unit. Since the patient could not be intubated by the standard method, because her larynx was up and forward, she was intubated successfully with a laryngeal mask airway through which two consecutive tracheal tubes were inserted. Conclusion: Laryngeal mask airway has an important role as a back‐up device in case direct visualization of the larynx is not possible.
Elastic and transport properties of cellular solids derived from three-dimensional tomographic images
Authors: Knackstedt Mark A , Arns Christoph H , Saadatfar Mohammad , Senden Tim J , Limaye Ajay , Sakellariou Arthur , Sheppard Adrian P , Sok Rob M , Schrof Wolfgang , Steininger H 
Published: April 2006

We describe a three-dimensional imaging and analysis study of eight industrial cellular foam morphologies. The foam morphologies were generated by differing industrial processing methods. Tomograms are acquired on an X-ray micro-computed tomography facility at scales of approximately equal to

at resolutions down to 7 μm. The image quality is sufficient in all cases to measure local structure and connectivity of the foamed material, and the field of view large enough to calculate a range of material properties. Phase separation into solid and porous components is straightforward.

Three-dimensional structural characteristics are measured directly on the porous and solid phases of the images. A number of morphological parameters are obtained, including pore volume-to-surface-area ratio, connectivity, the pore and solid phase size distributions defined by maximal sphere openings and chord length measurements. We further calculate the pore size distribution associated with capillary pressure via simulating of mercury drainage on the digital images.
The binarized microstructures are used as a basis for calculations of transport properties (fluid permeability, diffusivity and thermal conductivity) and elastic moduli. From the data, we generate property–porosity relationships for the range of foam morphologies imaged and quantitatively analyse the effects of porosity and microstructure on the resultant properties of the foams.

We compare our numerical data to commonly used theoretical and empirical property–porosity relationships. For thermal conductivity, we find that the numerical results agree extremely well with an empirical expression based on experimental data of various foams. The upper Hashin–Shtrikman bound also provides an excellent prediction of the data across all densities. From simulation of the diffusivity, we can define the tortuosity of the pore space within the cellular solid. We find that different processing methods lead to strong variations in the tortuosity of the pore space of the foams. For elastic properties, our results show that for the Young modulus,
E
, both the differential effective medium theory and the classical correlation

give a good correlation. Assuming a constant Poisson's ratio

leads to reasonable agreement. The best correlation for

is given by assuming a slight variation in

as a linear function of porosity. The permeability of the foams varies over three orders of magnitude. Correlations for permeability based on the classical Kozeny–Carman equation lead to reasonable agreement, except at the lowest porosities. Permeability estimations based on mercury porosimetry give excellent agreement for all foams.
Increase in BrAO1 gene expression and aldehyde oxidase activity during clubroot development in Chinese cabbage (Brassica rapa L.)
Authors: ANDO SUGIHIRO , TSUSHIMA SEIYA , TAGIRI AKEMI , KAMACHI SHINICHIRO , KONAGAYA KEN‐ICHI , HAGIO TAKASHI , TABEI YUTAKA 
Published: April 2006

SUMMARYIn clubroot disease, gall formation is induced by infection with the obligate biotroph Plasmodiophora brassicae due to increased levels of auxins and cytokinins. Because aldehyde oxidase (AO) may be involved in auxin biosynthesis in plants, we isolated two AO genes (BrAO1 and BrAO2) from Chinese cabbage (Brassica rapa ssp. pekinensis cv. Muso), which are the most similar to AAO1 among Arabidopsis AO genes, and examined their expressions during clubroot development. The expression of BrAO1 was enhanced in inoculated roots from 15 days post‐inoculation (dpi) when visible clubroots were still undetectable. Thereafter, BrAO1 expression increased with clubroot development compared with uninoculated roots, although BrAO2 expression was repressed. In situ hybridization revealed that BrAO1 was strongly expressed in tissues that were invaded by immature plasmodia at 35 dpi, suggesting that BrAO1 expression was enhanced by the pathogen in order to establish its pathogenesis. In addition, we detected AO activity, as evidenced by the occurrence of at least six bands (BrAO‐a to BrAO‐f) in the roots of Chinese cabbage using an active staining method with benzaldehyde and indlole‐3‐aldehyde as the substrate. Coincidental with BrAO1 expression, the signals of BrAO‐a and BrAO‐d increased with inoculation by P. brassicae during clubroot development compared with healthy roots, resulting in an increase in total AO activity. By contrast, the band BrAO‐b decreased post‐inoculation, in parallel with the expression of BrAO2. The other bands of activity were not clearly influenced by the infection. Based on these results, we discuss the involvement of AO in auxin‐overproduction during clubroot development in Chinese cabbage.
Introgression variability among Iberian brown trout Evolutionary Significant Units: the influence of local management and environmental features
Authors: ALMODÓVAR A. , NICOLA G. G. , ELVIRA B. , GARCÍA‐MARÍN J. L. 
Published: April 2006

Summary1. A comprehensive analysis was carried out on the effects of stocking on the genetic structure of Iberian brown trout evolutionary lineages. Introgression and genetic diversity were estimated from allozyme results of 307 populations based on own data (180) and available literature (127). Stocking records, angling regulations and environmental features related to hatchery trout performance were also analysed to determine the underlying mechanisms of the introgression effects.2. Fifty per cent of analysed populations showed introgression by genes of hatchery origin. The mean introgression estimated by the single locus approach was 0.134. An increment of both heterozygosity and polymorphism was observed when introgression increased in stream‐dwelling populations, which could finally produce a homogenisation of the genetic structure of populations and a decrease of the species’ genetic diversity.3. Introgression rate varied among Iberian evolutionary lineages (Evolutionary Significant Units), and was correlated with the stocking effort, except for the North Atlantic basins. The lack of adaptations for migratory behaviour in hatchery trout could explain the low impact of stocking in North Atlantic rivers where anadromous populations occur.4. Angling regulation did not seem to influence the survival of hatchery trout. Introgression tends to be higher in heavily stocked localities with fertile waters and stable discharge, which may favour the performance of hatchery trout.5. Trout management must be based on increasing population size by means of habitat improvement and sustainability of naturally reproducing wild stocks through appropriate angling regulations.
Isolation of precise plastid deletion mutants by homology‐based excision: a resource for site‐directed mutagenesis, multi‐gene changes and high‐throughput plastid transformation
Authors: Kode Vasumathi , Mudd Elisabeth A. , Iamtham Siriluck , Day Anil 
Published: April 2006

SummaryWe describe a simple and efficient homology‐based excision method to delete plastid genes. The procedure allows one or more adjacent plastid genes to be deleted without the retention of a marker gene. We used aadA‐based transformation to duplicate a 649 bp region of plastid DNA corresponding to the atpB promoter region. Efficient recombination between atpB repeats deletes the intervening foreign genes and 1984 bp of plastid DNA (co‐ordinates 57 424–59 317) containing the rbcL gene. Only five foreign bases are present in ΔrbcL plants illustrating the precision of homology‐based excision. Sequence analysis of non‐functional rbcL‐related sequences in ΔrbcL plants indicated an extra‐plastidic origin. Mutant ΔrbcL plants were heterotrophic, pale‐green and contained round plastids with reduced amounts of thylakoids. Restoration of autotrophy and leaf pigmentation following aadA‐based transformation with the wild‐type rbcL gene ruled out mutations in other genes. Excision and re‐use of aadA shows that, despite the multiplicity of plastid genomes, homology‐based excision ensures complete removal of functional aadA genes. Rescue of the ΔrbcL mutation and autotrophic growth stabilizes transgenic plastids in heteroplasmic transformants following antibiotic withdrawal, enhancing the overall efficiency of plastid transformation. Unlike the available set of homoplasmic knockout mutants in 25 plastid genes, the rbcL deletion mutant isolated here is readily transformed with the efficient aadA marker gene. This improvement in deletion design facilitates advanced studies that require the isolation of double mutants in distant plastid genes and the replacement of the deleted locus with site‐directed mutant alleles and is not easily achieved using other methods.