bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antenatal diagnosis and palliative treatment of non‐immune hydrops fetalis secondary to fetal parvovirus B19 infection
Authors: Naides Stanley J. , Weiner Carl P. 
Published: March 2007

AbstractHydrops fetalis was diagnosed at 22 weeks. An ultrasound examination demonstrated cardiomegaly and a fetal blood specimen obtained by cordocentesis revealed thrombocytopenia, anaemia, and neutropenia. Fetal paracentesis yielded straw‐coloured fluid with electrolytes indicative of a transudate. Non‐enveloped icosahedral viral particles approximately 23 mm in diameter were visualized in the ascitic fluid by electron microscopy. Immune electron microscopy confirmed human parvovirus B19. Direct fetal digitalization led to a reduction in umbilical artery resistance, a decline in the abdominal circumference from 20·3 to 17·8 cm, and resolution of the ascites within 72 h. Despite this dramatic response to therapy, fetal death occurred on day 5 of treatment. The initial maternal serum was positive for anti‐B19 IgM and IgG antibodies. Electron microscopy of fetal cardiac tissue obtained post‐mortem revealed intranuclear viral particles typical of B19, confirming the antenatal diagnosis of myocarditis. This case demonstrates that direct viral identification is applicable to prenatal diagnosis. To our knowledge, this is the first reported case of the antenatal diagnosis and palliative treatment of fetal viral infection.
Fetal two‐dimensional doppler echocardiography (colour flow mapping) and its place in prenatal diagnosis
Authors: Gembruch U. , Hansmann M. , Redel D. A. , Bald R. 
Published: March 2007

AbstractOne hundred and fifty fetuses between 16 and 38 weeks of gestation were studied by fetal echocardiography using colour‐coded two‐dimensional Doppler echocardiography. Two‐dimensional, M‐mode, and Doppler spectral analyses were also performed. In 14 fetuses, structural and/or functional abnormalities were detected. Abnormalities were correctly ruled out in all the other fetuses. The advantages of two‐dimensional Doppler echocardiography are (1) rapid screening for flow abnormalities in the fetal heart, and thus shortening of the Doppler examination time; (2) rapid diagnosis of valvular regurgitation, valvular stenosis, and abnormal shunting of blood across the interatrial and interventricular septa; and (3) facilitation of the diagnosis of complex congenital heart defects which in certain cases is possible only by using two‐dimensional Doppler echocardiography.
Prenatal diagnosis of chinese homozygous α‐thalassaemia 1 and haemoglobin H disease by analysis of α‐ and φζ‐globin genes in chorionic villi and amniocytes
Authors: Ko Tsang‐Ming , Hsieh Fon‐Jou , Hsu Pi‐Mei , Lee Tzu‐Yao 
Published: March 2007

AbstractEighty‐eight high‐risk pregnancies, 81 for homozygous α‐thalassaemia 1 and 7 for haemoglobin (Hb) H disease, were collected in this study. Chorionic villus sampling (CVS) was done in 63 cases and amniocentesis in 25 cases to obtain fetal cells. Southern blotting and DNA hybridization with α‐ and φζ‐globin gene probes were used to determine the α‐globin gene status. In two non‐informative families with non‐deletional mutations, DNA analysis failed to rule out the affected condition, and fetal blood sampling (FBS) and Hb electrophoresis were used for the final diagnosis.In the 81 fetuses at risk for homozygous α‐thalassaemia 1, 17 (13 by CVS and 4 by amniocentesis) were afffected, 30 were α‐thalassaemia 1 heterozygotes, 19 were normal, and the remaining 15 were either normal or heterozygous. In the seven fetuses at risk for Hb H disease, one was normal, three were α‐thalassaemia 1 heterozygotes, two were α‐thalassaemia 2 heterozygotes, and one was affected with Hb H disease and developed hydrops fetalis. DNA analysis on fetal cells enabled us to diagnose prenatally severe α‐thalassaemias, to prevent the birth of infants with Hb H disease, and to minimize maternal obstetrical complications from harbouring a fetus with Hb Bart's hydrops fetalis.
In utero ultrasonographic features of campomelic dysplasia
Authors: Cordone Massimo , Lituania Mario , Zampatti Caterina , Passamonti Ubaldo , Magnano Gian Michele , Tomà Paolo 
Published: March 2007

AbstractA prenatal diagnosis of campomelic dysplasia in a primigravida is described. First level fetal ultrasonography demonstrated bowing and shortening of lower limbs. Second level examination allowed the correct diagnosis by demonstrating several skeletal anomalies pathognomonic of campomelic dysplasia.
Amniotic fluid acetylcholinesterase measurement in the prenatal diagnosis of open neural tube defects. Second report of the collaborative acetylcholinesterase study
Authors: Wald Nicholas , Cuckle Howard , Nanchahal Kiran 
Published: March 2007

AbstractSeventeen centres from Australia, Britain, France, and the United States collaborated in a study to compare amniotic fluid acetylcholinesterase (AChE) determination by gel electrophoresis and amniotic fluid alpha‐fetoprotein (AFP) measurement as diagnostic tests for open neural tube defects. The study was based on 32 642 women with singleton pregnancies (including 428 with open spina bifida and 238 with anencephaly) who had an amniocentesis at 13–24 weeks' gestation. The AChE test yielded a detection rate for open spina bifida of 99 per cent (95 per cent confidence interval 98–100 per cent), 98 per cent for anencephaly (95 per cent confidence interval 96–100 per cent), and a false‐positive rate of 0.34 per cent (95 per cent confidence interval 0.28–0.40 per cent) excluding miscarriages, intrauterine death, and serious fetal abnormalities. The false‐positive rate was 0.30 per cent among the 13 centres that used a specific AChE inhibitor in the test. Comparable rates for the AFP test were less favourable. (For example, the open spina bifida detection rate was 90 per cent and the false‐positive rate was 0.46 per cent using the cut‐off levels specified in the U.K. Collaborative AFP Study.) The AChE false‐positive rate was lower in samples that were not bloodstained (0.16 per cent) than in those that were (2.4 per cent). It was higher in women who had an amniocentesis on account of a raised maternal serum AFP level (0.56 per cent) than in those who had one for other reasons (0.29 per cent). The best results were obtained by a combination of the two tests, an effective and economical policy being to perform the AFP measurement on all amniotic fluid samples and an AChE test on samples with AFP levels greater than or equal to 2.0 multiples of the normal median (about 5 per cent of all samples). Using this policy, the open spina bifida detection rate was 96 per cent and the false‐positive rate was 0.14 per cent (0.06 per cent for samples that were not bloodstained and 1.2 per cent for those that were; 0.40 per cent for women with raised serum AFP levels and 0.09 per cent for other women). This policy offers a useful improvement to the prenatal diagnosis of open spina bifida.
Prenatal diagnosis of a craniopharyngioma using ultrasonography and magnetic resonance imaging
Authors: Bailey Wendy , Freidenberg Gary R. , James Hector E. , Hesselink John R. , Jones Kenneth Lee 
Published: March 2007

AbstractWe report an infant with a craniopharyngioma which was detected in utero. Maternal uterine ultrasonography, done at 27 weeks because of polyhydramnios, revealed a 4 cm midline mass near the base of the fetal skull. At 31 weeks, magnetic resonance imaging of the maternal abdomen confirmed the presence of a mass in the region of the third ventricle and revealed hydrocephalus. Two days post‐partum a computed tomography (CT)‐guided needle biopsy of the mass was performed and recovered tissue which was histologically consistent with a craniopharyngioma. The infant' s postnatal period was complicated by seizures, which were treated with phenobarbital, and by progressive hydrocephalus, necessitating placement of a ventriculo‐peritoneal shunt. He also received therapy for central hypothyroidism and diabetes insipidus. The infant' s parents refused permission for attempted resection of the tumour and he died at 8 weeks of age.This represents the second reported case of an antenatally detected craniopharyngioma. Four other cases of different intracranial tumours have been detected in utero using ultrasound, with no reported survivors past 3 days of age. There is a uniformly poor prognosis of such infants, but earlier diagnosis and intervention may change this result.
Synthesis and properties of solvent absorptive methyl methacrylate‐divinylbenzene copolymer beads
Authors: Aungsupravate Ornsiri , Kangwansupamonkon Wiyong , Chavasiri Warinthorn , Kiatkamjornwong Suda 
Published: March 2007

AbstractMethyl methacrylate‐divinylbenzene copolymer beads were synthesized by radical suspension polymerization. The effects of the divinylbenzene concentration and the composition of the toluene/heptane diluent were studied with regard to the polymer bead formation, surface morphology, solvent swelling ratio, and absorption kinetics. The crosslinking density and diluent composition were responsible for solvent swelling. The interaction between the polymer and the diluents is attributed to phase separation, which controls the formation of a network‐type or pore‐type polymer, or a combination. For the optimum bead swelling in toluene, a combined morphology of more flexible polymer networks and a small amount of pores is essential for the desired absorption–desorption behavior. Dynamic swelling behavior of the polymer beads was elucidated. The mechanism of toluene transport into the beads became more a relaxation control. POLYM. ENG. SCI., 47:447–459, 2007. © 2007 Society of Plastics Engineers.
An investigation on the application of predictive control for controlling screw position and velocity on an injection molding machine
Authors: Dubay Rickey , Pramujati Bambang , Han Jianguo , Strohmaier Franz 
Published: March 2007

AbstractInjection velocity is one of the key parameters in the injection molding process that has significant effect on part quality, influencing common problems, such as flashing and short shots. Different products require specific molding conditions, including mold and melt temperatures, velocity profiles, and polymers, making the injection velocity dynamics vary significantly and difficult for high precision velocity control. Two predictive controllers were developed to control the screw injection velocity. The first approach uses a position sensor as feedback and a simplified predictive controller to track an injection velocity setpoint profile. The controller was developed and implemented utilizing single‐step change and multistep change open loop tests. The second strategy uses a multimodel dynamic matrix predictive controller to overcome the nonlinear characteristics of the injection velocity dynamics as the mold is being filled. Velocity feedback is provided by high speed processing of the position analog signal. This approach utilizes several open loop injection velocity profiles to generate corresponding dynamic matrices for the controller. As a result, this controller is modified or retuned automatically when setpoint changes in injection velocity occur, as well as when using different polymers and molds. The close loop results for both simulations and real time control have demonstrated that the two predictive controllers provided good setpoint tracking performance for wide ranging position and velocity profiles. POLYM. ENG. SCI., 47:390–399, 2007. © 2007 Society of Plastics Engineers.
Semiempirical equations for the viscosity of amphiphilic polymer solutions: A critical examination
Authors: Durand A. 
Published: March 2007

AbstractThe associative behavior of amphiphilic polysaccharides derived from dextran, a neutral bacterial polysaccharide, is studied in dilute and moderately concentrated aqueous solutions using viscosity measurements. It is shown that the viscosity of the aqueous solutions can be conveniently depicted over a wide concentration range by several semiempirical equations. The Martin equation as well as the Matsuoka‐Cowman equation is shown to depict conveniently the experimental results. These two equations involve only viscometric parameters determined in the dilute range (intrinsic viscosity and Huggins constant). The modification of Lyons and Tobolsky is discussed. The Fedors equation is shown to be similar to the Heller equation over a large concentration domain. Their respective empirical parameters are correlated and can be calculated from the Huggins coefficient. POLYM. ENG. SCI., 47:481–488, 2007. © 2007 Society of Plastics Engineers.
Study of the magnetic microstructure of high‐coercivity sintered SmCo5 permanent magnets with the conventional Bitter pattern technique and the colloid‐SEM method
Authors: Szmaja Witold 
Published: March 2007

Abstract The magnetic microstructure of high‐coercivity sintered SmCo5 permanent magnets was studied with the conventional Bitter pattern technique, and also for the first time with the colloid‐scanning electron microscopy (colloid‐SEM) method. Both techniques were supported by digital image acquisition, enhancement and analysis. Thanks to this, it was possible to obtain high‐contrast and clear images of the magnetic microstructure and to analyze them in detail, and consequently also to achieve improvements over earlier results. In the thermally demagnetized state the grains were composed of magnetic domains. On the surface perpendicular to the alignment axis, the main domains forming a maze pattern and surface reverse spikes were observed. Investigations on the surface parallel to the alignment axis, especially by the colloid‐SEM technique, provided a detailed insight into the orientation of grains. The alignment of grains was good, but certainly not perfect; there were also strongly misaligned grains, although generally very rare. In most cases the domain structures within grains were independent of their neighbors, but in some cases (not so rare) the domain walls were observed to continue through the grain boundaries, indicating significant magnetostatic interaction between neighboring grains. Studies of the behavior of the magnetic microstructure under the influence of an external magnetic field, performed for the first time on the surface parallel to the alignment axis (with the conventional Bitter pattern method), showed that the domain walls move easily within the grains and that the magnetization reversal mechanism is mainly related to the nucleation and growth of reverse domains, i.e. that sintered SmCo5 magnets are nucleation‐dominated systems. Groupwise magnetization reversal of adjacent magnetically coupled grains was observed, an unfavorable effect for high‐coercivity magnets. Images obtained by the colloid‐SEM technique and the conventional Bitter pattern method were compared and some aspects related to the observation of magnetic microstructures by these two techniques were also discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recombination processes in rare‐earth doped MAl2O4 (M = Ca, Sr) persistent phosphors investigated by optically‐detected magnetic resonance
Authors: Schweizer S. , Henke B. , Rogulis U. , Yen W. M. 
Published: March 2007

AbstractSingle crystalline MAl2O4 (M = Ca and Sr) persistent phosphors, which are nominally pure or additionally doped with Eu and Nd or Dy, respectively, were investigated for their recombination luminescence (RL) and microwave‐induced changes in the RL at low temperatures. The analysis of the optically‐detected electron paramagnetic resonance (EPR) spectra, recorded after ultraviolet excitation at 4.2 K, shows that intrinsic donor and acceptor centres are involved in the recombination process. Spectral dependent RL‐EPR measurements on undoped CaAl2O4 (CAO) and SrAl2O4 (SAO) show that we deal with only one donor but at least two different acceptors. The g value of the donor is 1.99 in CAO and 1.97 in SAO; the g value of the acceptors is about 2.02. The donor–acceptor recombination energy is either emitted directly (undoped samples) or almost completely transferred to the rare‐earth activators (doped samples). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence from europium, europium–chromium, erbium, samarium and terbium‐activated powder, ceramic and polycrystalline cubic boron nitride
Authors: Shishonok E. M. , Leonchik S. V. , Steeds J. W. 
Published: March 2007

AbstractA wide range of luminescent materials has been produced based on cubic boron nitride and studied by photoluminescence spectroscopy at room temperature and 7 K. These materials were in the form of micropowders, ceramic compacts and polycrystalline aggregates. The luminescence was excited by 325 nm or 488 nm excitation of Eu, Eu–Cr, Er, Sm and Tb additions to the various preparations. Eu–Cr pair emission has been discovered for the first time with its main line at 686 nm in Eu and Cr codoped polycrystalline cBN. The emitted light, which was quite intense in some cases, spanned a wide range of the visible spectrum. It was often highly structured and could be related to the well‐known emission characteristics of the 3+ charge states of the relevant ions. The materials have potential applications as phosphors that are required to operate in extreme environmental conditions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Calorimetric study and Landau analysis of the phase transitions in PbZr1–xSnxO3 single crystals with 0 ≤ x ≤ 0.4
Authors: Jankowska‐Sumara Irena 
Published: March 2007

AbstractDifferential scanning calorimetry experiments have been performed for PbZr1–x Snx O3 single crystals where 0 ≤ x ≤ 0.4 at the temperature range of 100–600 K. The temperatures and orders of particular phase transitions have been determined and the phase diagram was compared to dielectric measurements. The first order character of the phase transitions in PbZr1–x Snx O3 was discussed. The total transitions energy and entropy at the phase transitions were calculated. The excess specific heat and excess entropy associated with the phase transitions were analysed using Landau theory. The comparison of calorimetric data with the evolution of the order parameter indicates that the phase transitions in PbZr1–x Snx O3 single crystals seem to follow a mean field Landau potential. The results are compared to the earlier dielectric and birefringence experiments. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DFT studies on the mechanism of the reaction of C2H5S with NO2
Authors: Tang Yi‐Zhen , Sun Hao , Pan Ya‐Ru , Pan Xiu‐Mei , Wang Rong‐Shun 
Published: March 2007

AbstractThe mechanisms for the reaction of C2H5S with NO2 are investigated at the QCISD(T)/6‐311++G(d, p)//B3LYP/6‐311++G(d, p) level on both single and triple potential energy surfaces. The geometries, vibrational frequencies and zero‐point energy (ZPE) corrections of all stationary points involved in the title reaction are calculated at the B3LYP/6‐311++G(d, p) level. The results show that the reaction is more predominant on the single potential energy surface, while it is negligible on the triple potential energy surface. Without barrier height in the whole process, the major channel is R → C2H5SONO (IM1 and IM2) → P1 (C2H5SO+NO). With much heat released in the formation of C2H5SNO2 (IM3) and the transition state involved in the subsequent step more stable than reactants, P4 (CH3CHS + t‐HONO) is subdominant product energetically. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
CEGMA: a pipeline to accurately annotate core genes in eukaryotic genomes
Authors: Parra Genis , Bradnam Keith , Korf Ian 
Published: March 2007

AbstractMotivation: The numbers of finished and ongoing genome projects are increasing at a rapid rate, and providing the catalog of genes for these new genomes is a key challenge. Obtaining a set of well-characterized genes is a basic requirement in the initial steps of any genome annotation process. An accurate set of genes is needed in order to learn about species-specific properties, to train gene-finding programs, and to validate automatic predictions. Unfortunately, many new genome projects lack comprehensive experimental data to derive a reliable initial set of genes.Results: In this study, we report a computational method, CEGMA (Core Eukaryotic Genes Mapping Approach), for building a highly reliable set of gene annotations in the absence of experimental data. We define a set of conserved protein families that occur in a wide range of eukaryotes, and present a mapping procedure that accurately identifies their exon–intron structures in a novel genomic sequence. CEGMA includes the use of profile-hidden Markov models to ensure the reliability of the gene structures. Our procedure allows one to build an initial set of reliable gene annotations in potentially any eukaryotic genome, even those in draft stages.Availability: Software and data sets are available online at http://korflab.ucdavis.edu/Datasets.Contact: ifkorf@ucdavis.eduSupplementary information: Supplementary data are available at Bioinformatics online.
rh_tsp_map3.0: end-to-end radiation hybrid mapping with improved speed and quality control
Authors: Schäffer Alejandro A. , Rice Edward Stallknecht , Cook William , Agarwala Richa 
Published: March 2007

AbstractSummary: rh_tsp_map is a software package for computing radiation hybrid (RH) maps and for integrating physical and genetic maps. It solves the central mapping instances by reducing them to the traveling salesman problem (TSP) and using a modification of the CONCORDE package to solve the TSP instances. We present some of the features added between the initial rh_tsp_map version 1.0 and the current version 3.0, emphasizing the automation of many steps and addition of various checks designed to find problems with the input data. Iterations of improved input data followed by fast re-computation of the maps improves the quality of the final maps.Availability: rh_tsp_map source code and documentation including a tutorial is available at ftp://ftp.ncbi.nih.gov/pub/agarwala/rhmapping/rh_tsp_map.tar.gz. CONCORDE modified for RH mapping is available in the directory http://www.isye.gatech.edu/~wcook/rh/. The QSopt library needed for CONCORDE is available at http://www2.isye.gatech.edu/~wcook/qsopt/downloads/downloads.htmContact: richa@helix.nih.gov, FAX: 301-480-2288. (Please send email concurrently with any fax.)