bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spin polarized transport of iron nitride Fe4N: Analysis using a combination of first principles calculation and model calculation
Authors: Kokado Satoshi , Fujima Nobuhisa , Harigaya Kikuo , Shimizu Hisashi , Sakuma Akimasa 
Published: July 2006

AbstractTo propose a ferromagnet exhibiting a highly spin‐polarized transport, we analyze the spin polarization ratio of the bulk Fe4N (Curie temperature: 761 K), which is focused on by taking into account the fact that a ferromagnetic electrode containing Fe and a light element enhances the tunnel magnetoresistance effect at room temperature. The spin polarization ratio is here defined by P = (σ ↑ – σ ↓)/(σ ↑ + σ ↓), with σ ↑ (σ ↓) being the conductivity at zero temperature of up spin (down spin). The conductivity is obtained using the Kubo formula and the Slater‐Koster tight binding model, where parameters are determined by fitting the band structure of the model to that of the first principles calculation. In the vicinity of the Fermi energy, |P | takes almost 1.0, which is 5.0 times as large as that of bcc‐Fe. It may suggest that Fe4N is very effective as a spin injection electrode. Also, by comparing Fe4N to fcc‐Fe in the ferromagnetic state with the equilibrium lattice constant of Fe4N, it is shown that N plays an important role in increasing |P |. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First principles calculation of electric and magnetic properties of UIn3 intermetalic compound
Authors: Nourbakhsh Z. , Pourghazi A. 
Published: July 2006

AbstractThe electronic and magnetic properties of UIn3 have been calculated in the presence of spin orbit coupling using density functional theory (DFT) by the Wien2k package, and an anti‐ferromagnetic ground state structure has been found for this compound. The spin and orbital magnetic moments has been found for this compound. The spin and orbital magnetic moment have been calculated, and it has been shown the orbital magnetic moment is directed opposite to the spin magnetic moment. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spontaneous polarization in the tetragonal, orthorhombic and rhombohedral phases of KNbO3
Authors: Toumanari Ahmed , El‐frikhe Es‐saïd , Khatib Driss 
Published: July 2006

AbstractThe spontaneous polarization and the refractive indices in the tetragonal, orthorhombic and rhombohedral phases of KNbO3 are discussed quantitatively from the microscopic consideration. The shift of the Nb ion situated at the centre of the lattice is calculated at various temperatures from the mean field approximation model. The spontaneous polarization has been calculated by the dipole‐dipole model using the calculated values of the shift of the Nb ions, the vertical strains and the shearings. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Developing New Cleavage Strategies in a Fluorous Phase Pummerer Cyclative‐Capture Approach for the Synthesis of N‐Heterocycles
Authors: McCormick Rosemary A. , James Karen M. , Willetts Nigel , Procter David J. 
Published: August 2006

AbstractAn efficient, oxidative cleavage of a sulfur linker has been developed for the fluorous phase synthesis of N‐heterocycles. The new cleavage strategy facilitates the synthesis of products containing diverse structural features.
Density matrix calculations of gaseous and adsorbate dynamics in electronically excited molecular systems
Authors: Micha David A. 
Published: August 2006

AbstractThis contribution deals with two approaches for localized phenomena in excited many‐atom systems. The first approach develops a quantum quasi‐classical treatment for the density operator, including all atoms. It is based on a partial Wigner representation and is illustrated with applications to photodissociation of NaI, and to light emission of excited Li interacting with a He cluster. This second application describes the direct dynamics with a time‐dependent electronic density matrix, expanded in a basis set of atomic functions. It shows that such an approach can deal with electronically excited many‐atom systems involving tens of quantum states and hundreds of classical variables. The second approach makes use of the reduced density operator description for a system in a medium. This allows for dissipative dynamics, which can be instantaneous or delayed. An application is presented for femtosecond photodesorption using a Markovian dissipation and construction of the density operator from density amplitudes, for CO/Cu(001). A second application of a reduced density operator has been made to vibrational relaxation of adsorbates, solving integrodifferential equations to compare delayed, instantaneous, and Markovian dissipation. It is concluded that delayed dissipation is needed at short times and that a Markovian treatment is suitable for the interpretation of cross‐sectional measurements that involve long‐term dynamics. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
U‐PVC gelation level assessment, part 2: Optimization of the differential scanning calorimetry technique
Authors: Fillot Louise‐Anne , Hajji Philippe , Gauthier Catherine 
Published: July 2006

AbstractDifferential scanning calorimetry (DSC) is one of the best techniques for assessing PVC gelation level. Thus, it is of great interest to understand and optimize the different aspects of the DSC method. In the present study, DSC experiments were carried out on PVC dryblend samples that were previously heat‐treated at different temperatures. Practical aspects such as sample preparation, heating rate, and ending temperature are described. Then, the obtained DSC patterns are compared and analyzed to clarify the origin of the measured events. The effects of PVC reprocessing on DSC patterns are presented, as well as the effects of heterogeneity issues (i) at the scale of a PVC window profile and (ii) at the scale of a PVC DSC sample. The method used for the determination of the gelation level is then analyzed. The choice of the integration limits that strongly affect the melting enthalpy values is discussed. Different ways of calculating the gelation level, including the conventional definition involving the ratio A/A + B as well as new approaches, are proposed. J. VINYL. ADDIT. TECHNOL. 12:108–114, 2006. © 2006 Society of Plastics Engineers.
Critical assessment of chitotriosidase analysis in the rational laboratory diagnosis of children with Gaucher disease and Niemann–Pick disease type A/B and C
Authors: Ries Markus , Schaefer Ellen , Lührs Till , Mani Latha , Kuhn Jana , Vanier Marie T. , Krummenauer Frank , Gal Andreas , Beck Michael , Mengel Eugen 
Published: July 2006

SummaryLaboratory diagnosis of lysosomal storage disorders, especially sphingomyelinase deficiency (Niemann–Pick disease type A/B) and Niemann–Pick disease type C (NPC) can be challenging. We therefore aimed to analyse the feasibility of first‐step screening with specific chitotriosidase cut‐off values in children ≤ 10 years of age with visceral organomegaly (hepatomegaly, splenomegaly, or hepatosplenomegaly) in whom a storage disorder was suspected. We conducted a retrospective, cross‐sectional, referral, single‐centre study to assess diagnostic test properties in 106 individuals. Median chitotriosidase activity was 12 655 nmol/h per ml (interquartile range 4693–20982) in Gaucher disease (GD); 780 (465–1298) in SMD (sphingomyelinase deficiency); 925 (319–1215) in NPC and 50 (29–54) in patients with miscellaneous diseases. To restrict the differential diagnosis to GD, SMD or NPC, chitotriosidase activity above 200 nmol/h per ml had a sensitivity of 96%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 95%. For GD alone, chitotriosidase activity above 4000 nmol/h per ml had a sensitivity of 77%, specificity of 100%, PPV of 100% and NPV of 92%. Of the 44 patients analysed, 4.5% were homozygous and 36.4% heterozygous for chitotriosidase gene duplication. Adjusting for the chitotriosidase genotype, chitotriosidase activities were higher in GD type III than in GD type I. We conclude that, in the above setting, the degree of elevation of chitotriosidase activity can be applied to increase the likelihood of GD, SMD, or NPC and guide the choice of the appropriate confirmatory assay.
Reaction time, inhibition, working memory and ‘delay aversion’ performance: genetic influences and their interpretation
Authors: KUNTSI JONNA , ROGERS HANNAH , SWINARD GREER , BÖRGER NORBERT , MEERE JAAP van der , RIJSDIJK FRUHLING , ASHERSON PHILIP 
Published: August 2006

Background. For candidate endophenotypes to be useful for psychiatric genetic research, they first of all need to show significant genetic influences. To address the relative lack of previous data, we set to investigate the extent of genetic and environmental influences on performance in a set of theoretically driven cognitive-experimental tasks in a large twin sample. We further aimed to illustrate how test–retest reliability of the measures affects the estimates.Method. Four-hundred 7- to 9-year-old twin pairs were assessed individually on tasks measuring reaction time, inhibition, working memory and ‘delay aversion’ performance. Test–retest reliability data on some of the key measures were available from a previous study.Results. Several key measures of reaction time, inhibition and working-memory performance indicated a moderate degree of genetic influence. Combining data across theoretically related tasks increased the heritability estimates, as illustrated by the heritability estimates of 60% for mean reaction time and 50% for reaction-time variability. Psychometric properties (reliability or ceiling effects) had a substantial influence on the estimates for some measures.Conclusions. The data support the usefulness of several of the variables for endophenotype studies that aim to link genes to cognitive and motivational processes. Importantly, the data also illustrate specific conditions under which the true extent of genetic influences may be underestimated and hence the usefulness for genetic mapping studies compromised, and suggest ways to address this.
Psychiatric and psychosomatic symptoms are increasing problems among Swedish schoolchildren
Authors: Cederquist Åse Victorin 
Published: August 2006

AbstractPaediatricians and other professionals in Sweden note that the amount of children with psychiatric and psychosomatic symptoms is growing in number. Suicide attempts among the young (15–24 y) increased by more than 30% from 1998–2003. The Swedish National Board for Health and Welfare's 2004 guidelines for school healthcare shed light on this increasing problem among schoolchildren. An article in this issue of Acta Paediatrica, “Living conditions and psychosomatic complaints in Swedish schoolchildren”, analyses economic stress as a causative factor leading to psychosomatic symptoms such as headache, abdominal pain and difficulty in falling asleep. Living conditions, however, most likely include other factors related to our modern and ever‐changing society that also have an impact on the growing child.Conclusion: Psychiatric health is changing for the worse among Swedish schoolchildren. The cause is multifactorial. Economic stress is one factor, but there are also other possible causes related to modern society that correlate to the increase of psychosomatic problems among schoolchildren. Three major problems are among those suspected: impaired education and deficient working environment in Swedish schools, a general lack of adult contact and guidance, and excessive computer and TV use.
Activated Osteoclasts with CD51/61 Expression in Otosclerosis
Authors: Karosi Tamás , Jókay István , Kónya József , Petkó Mihály , Szabó László Z. , Pytel József , Jóri József , Sziklai István 
Published: August 2006

AbstractHypothesis: Stapes ankylosis is supposed to be a disease with variable histopathology caused by otosclerosis or pseudo‐otosclerosis. Persistent measles virus infection of the otic capsule could induce reactivation of quiescent embryonic osteoclasts in otosclerosis.Background: Presence of measles virus RNA was demonstrated in the footplates of otosclerotic patients by reverse‐transcription polymerase chain reaction (RT‐PCR). Histology of active otosclerosis is featured by the presence of numerous osteoclasts with unknown phenotype.Methods: Nucleic acid was extracted from stapes footplates of clinically otosclerotic patients (n = 261). Genomic RNA of measles virus was amplified by RT‐PCR. Amplification results were correlated to postoperative histologic and CD51/61 specific immunohistologic findings. A parallel alcalic phosphatase activity assessment was performed to evaluate the metabolic activity of osteoclasts in each section.Results: Among 261 stapes fixation cases, 175 otosclerotic stapes contained measles virus RNA. Histology for virus negative stapes (n = 86) represented nonotosclerotic, degenerative disorders. Histologically confirmed otosclerosis was featured by the presence of osteoclasts with renewed, embryonic phenotype. In otosclerosis, alcalic phosphatase activity was significantly higher compared with nonotosclerotic stapes ankylosis (P < .001).Conclusion: The presence of CD51/61 positive osteoclasts in otosclerotic bone containing viral sequences provides the basis for an inflammatory bone remodeling disorder. Otosclerosis is a disease caused by persistent measles virus infection and reactivation of resting embryonic osteoclasts in the otic capsule.
Divergence of Fine and Gross Motor Skills in Prelingually Deaf Children: Implications for Cochlear Implantation
Authors: Horn David L. , Pisoni David B. , Miyamoto Richard T. 
Published: August 2006

AbstractObjective: The objective of this study was to assess relations between fine and gross motor development and spoken language processing skills in pediatric cochlear implant users.Study Design: The authors conducted a retrospective analysis of longitudinal data.Methods: Prelingually deaf children who received a cochlear implant before age 5 and had no known developmental delay or cognitive impairment were included in the study. Fine and gross motor development were assessed before implantation using the Vineland Adaptive Behavioral Scales, a standardized parental report of adaptive behavior. Fine and gross motor scores reflected a given child's motor functioning with respect to a normative sample of typically developing, normal‐hearing children. Relations between these preimplant scores and postimplant spoken language outcomes were assessed.Results: In general, gross motor scores were found to be positively related to chronologic age, whereas the opposite trend was observed for fine motor scores. Fine motor scores were more strongly correlated with postimplant expressive and receptive language scores than gross motor scores.Conclusions: Our findings suggest a disassociation between fine and gross motor development in prelingually deaf children: fine motor skills, in contrast to gross motor skills, tend to be delayed as the prelingually deaf children get older. These findings provide new knowledge about the links between motor and spoken language development and suggest that auditory deprivation may lead to atypical development of certain motor and language skills that share common cortical processing resources.
Dramatic Changes in Home‐based Enteral Nutrition Practices in Children During an 11‐year Period
Authors: Daveluy Walter , Guimber Dominique , Uhlen Stéphanie , Lescut Dominique , Michaud Laurent , Turck Dominique , Gottrand Frédéric 
Published: July 2006

ABSTRACTObjectives:Experience with pediatric home‐based enteral nutrition (HEN), in particular series including children only, has been reported only rarely. We investigated the evolution of pediatric HEN activity during an 11‐year period.Methods:All patients aged 17 years or younger who started HEN between January 1990 and December 2000 were included in this retrospective study.Results:The annual number of patients treated with HEN increased dramatically from 16 in 1990 to 200 in 2000, with more than 65 new patients every year since 1999 (P < 0.0001). The mean age at the commencement of HEN decreased from 6.2 ± 1.4 (SEM) to 4.8 ± 0.7 years (P = 0.006). The use of nasogastric tubes decreased from 63% in 1990 to 35% in 1998 (P = 0.009), and the use of gastrostomy increased from 50% to 60% from 1994 onward. The proportion of patients with digestive diseases commencing HEN in each year decreased from more than 40% before 1996 to less than 32% in 2000 (P = 0.009). Commercially manufactured pediatric diets were used increasingly (P = 0.0006).Conclusions:The evolution of HEN was marked by changes in the population treated and the modes of treatment after the emergence of gastrostomy and commercial diets. This justified the creation of a multidisciplinary, pediatric artificial nutrition unit.
Probiotic Intervention in the First Months of Life
Authors: Rinne Minna , Kalliomäki Marko , Salminen Seppo , Isolauri Erika 
Published: July 2006

ABSTRACTObjectives:To determine whether probiotics administered for 6 months postnatally affect gastrointestinal symptoms, crying and the compositional development of the gut microbiota through infancy.Methods:The study comprised of 132 newborns whose mothers were randomized to receive placebo or Lactobacillus rhamnosus GG (ATCC 53103) before delivery. The treatments of mothers/infants continued for 6 months postnatally. A specific symptom chart was used to monitor gastrointestinal symptoms and infant's crying during the 7th and the 12th weeks of life. Fluorescent in situ hybridization was used to establish the Bifidobacterium, Lactobacillus/Enterococcus, Bacteroides and Clostridium counts in fecal samples at 6, 12, 18 and 24 months of age.Results:Numbers of different types of stools, vomits and crying time were comparable between the groups during the 7th and the 12th weeks of life. Dominant microbiota consisted of bifidobacteria throughout the study. At 6 months, there were less clostridia in faeces in the placebo compared with the probiotic group (P = 0.026), whereas after long‐term follow‐up at 2 years, there were less lactobacilli/enterococci and clostridia in faeces in the probiotic group than in the placebo group (P = 0.011 and P = 0.032, respectively), reflecting the impact of clostridia as a marker of microbiota succession in healthy infants.Conclusions:Probiotic administration in the first months of life was well tolerated and did not significantly interfere with long‐term composition or quantity of gut microbiota.
What Is the Evidence on the Practice of Mucous Fistula Refeeding in Neonates With Short Bowel Syndrome?
Authors: Richardson Lydia , Banerjee Sujoy , Rabe Heike 
Published: July 2006

ABSTRACTA systematic review of literature was performed on the practice of mucous fistula refeeding in neonates with short bowel syndrome. No randomised controlled studies were identified. Case series reports of 30 infants showed improved weight gain (from −2.36 ± 1.24 to 21.06 ± 3.02 g/d) and reduced need for total parenteral nutrition. Randomised controlled trials are required to establish the benefits of mucous fistula refeeding in this condition.
Gene Transfer to the Gastrointestinal Tract After Peroral Administration of Recombinant Adeno‐associated Virus Type 2 Vectors
Authors: Shao Guohong , Greathouse Kristin , Huang Qin , Wang Chiou‐Miin , Sferra Thomas J. 
Published: July 2006

ABSTRACTObjectives:The transfer of exogenous genetic material to cells within the gastrointestinal (GI) tract has many potential therapeutic applications. An attractive feature of the GI tract for gene transfer is its accessibility through the orogastric route. In this study, we evaluated the stability of recombinant adeno‐associated virus type 2 (rAAV2) vectors within the GI tract and whether rAAV2‐mediated gene transfer could be increased through manipulation of the intraluminal environment.Methods:The stability of rAAV2 vectors carrying β‐galactosidase and enhanced green fluorescence protein transgenes was determined in the presence of hydrochloric acid, pepsin, trypsin, chymotrypsin gastric fluid and intestinal fluid and after in vivo administration. For in vivo experiments, the rAAV2 vector carrying the β‐galactosidase transgene was administered perorally to FVB/NJ mice. Groups of mice received the vector alone or in combination with sodium bicarbonate and aprotinin. Gene transfer to the stomach and small intestine was evaluated by polymerase chain reaction and histochemical assays.Results:The stability of rAAV2 was reduced by hydrochloric acid, trypsin, chymotrypsin, gastric fluid and intestinal fluid. The vector was not stable within the lumen of the GI tract. Gastric acid neutralization with sodium bicarbonate and protease inhibition with aprotinin increased the in vivo stability of the vector and the level of gene transfer to the stomach and all regions of the small bowel. In both groups of mice (vector alone and vector plus sodium bicarbonate and aprotinin), transgene‐derived protein expression (β‐galactosidase) was below the level of detection of the histochemical assay.Conclusions:Recombinant AAV2 are adversely affected by physiological conditions within the proximal GI tract. Gastric acid neutralization and inhibition of intestinal protease activity improved rAAV2 stability and increased the level of gene transfer within the GI tract. Despite these changes, transduction of the GI tract after peroral rAAV2 administration remained low.
Glucagon‐like Peptide 2 Stimulates Intestinal Nutrient Absorption in Parenterally Fed Newborn Pigs
Authors: Sangild P.T. , Tappenden K.A. , Malo C. , Petersen Y.M. , Elnif J. , Bartholome A.L. , Buddington R.K. 
Published: July 2006

ABSTRACTObjectives:Parenteral nutrition is a critically important intervention for children with intestinal dysfunctions. However, total parenteral nutrition (TPN) with no enteral feeding is associated with small intestine atrophy and malabsorption, which complicate the transition to enteral nutrition. The objective of the present study was to evaluate the therapeutic potential of the intestinotrophic peptide glucagon‐like peptide 2 (GLP‐2), which reduces TPN‐associated atrophy and maintains nutrient absorption in adult rats, for preventing nutrient malabsorption in neonates receiving TPN.Methods:Term pigs obtained by cesarean delivery received from birth TPN alone (TPN; n = 7) or TPN with GLP‐2 (25 nmol · kg−1 · d−1; GLP‐2; n = 8) or were fed sow milk enterally (n = 7). The small intestine was removed on postnatal day 6 to measure morphological responses and absorption of glucose, leucine, lysine and proline by intact tissues and brush border membrane vesicles and to quantify the abundances of mRNA and protein for enterocyte glucose transporters (SGLT‐1 and GLUT2).Results:Relative to TPN alone, administration of GLP‐2 resulted in small intestines that were larger (P < 0.01), had greater abundances of mRNA and protein for SGLT‐1, but not for GLUT2, and had higher capacities to absorb nutrients (P < 0.01). Moreover, the intestines of GLP‐2 pigs were comparable in size and absorptive capacities with those of pigs fed sow milk enterally.Conclusions:Providing GLP‐2 to neonates receiving TPN prevents small intestine atrophy, results in small intestine absorptive capacities that are comparable to when nutrients are provided enterally and may accelerate the transition from TPN to enteral nutrition.