bluuebunny/crossref_metadata_2025_split huggingface dataset:
Women's Views of Pregnancy Ultrasound: A Systematic Review
Authors: Garcia Jo , Bricker Leanne , Henderson Jane , Martin Marie‐Anne , Mugford Miranda , Nielson Jim , Roberts Tracy 
Published: February 2003

ABSTRACT: Background: Ultrasound has become a routine part of care for pregnant women in most countries with developed health services. It is one of a range of techniques used in screening and diagnosis, but it differs from most others because of the direct access that it gives parents to images of the fetus. A review of women's views of ultrasound was commissioned as part of a larger study of the clinical and economic aspects of routine antenatal ultrasound use.Methods: Studies of women's views about antenatal screening and diagnosis were searched for on electronic databases. Studies about pregnancy ultrasound were then identified from this material. Further studies were found by contacting researchers, hand searches, and following up references. The searches were not intentionally limited by date or language. Studies that reported direct data from women about pregnancy ultrasound were then included in a structured review. Studies were not excluded on the basis of methodological quality unless they were impossible to understand. They were read by one author and tabulated. The review then addressed a series of questions in a nonquantitative way.Results: The structured review included 74 primary studies represented by 98 reports. Studies from 18 countries were included, and they employed methods ranging from qualitative interviewing to psychometric testing. The review included studies from the very early period of ultrasound use up to reports of research on contemporary practice. Ultrasound is very attractive to women and families. Women's early concerns about the safety of ultrasound were rarely reported in more recent research. Women often lack information about the purposes for which an ultrasound scan is being done and the technical limitations of the procedure. The strong appeal of diagnostic ultrasound use may contribute to the fact that pregnant women are often unprepared for adverse findings.Conclusions: Despite the highly varied study designs and contexts for the research included, this review provided useful information about women's views of pregnancy ultrasound. One key finding for clinicians was the need for all staff, women, and partners to be well informed about the specific purposes of ultrasound scans and what they can and cannot achieve. (BIRTH 29:4 December 2002)
Racial and Ethnic Disparities in Breastfeeding among United States Infants: Third National Health and Nutrition Examination Survey, 1988–1994
Authors: Li Ruowei , Grummer‐Strawn Laurence 
Published: February 2003

ABSTRACT: Background: The studies suggesting that blacks are less likely to initiate and maintain breastfeeding than whites in the United States are limited either by the representativeness of the sample or by the ambiguousness of attribution of racial and ethnic disparities to generally poor socioeconomic status among blacks. The purpose of this study was to examine racial and ethnic disparities in breastfeeding rates among U.S. infants using national representative data.Methods: We analyzed breastfeeding data reported by parents of children ages 12 to 71 months at the time of interview from the Third National Health and Nutrition Examination Survey (1988–1994). Breastfeeding data were stratified by both race and ethnicity, and by a series of sociodemographic and health‐related characteristics.Results: The proportion of children ever breastfed was 60 percent among non‐Hispanic whites, 26 percent among non‐Hispanic blacks, and 54 percent among Mexican Americans. By 6 months postpartum, the proportion still breastfed decreased to 27, 9, and 23 percent, correspondently. Blacks also had a significantly lower rate of exclusive breastfeeding at 4 months than whites (14%). In addition, the differentials in breastfeeding rates between high and low socioeconomic classes were most substantial among blacks.Conclusions: Blacks had consistent lower breastfeeding rates than whites regardless of their sociodemographic status. The large differentials between high and low socioeconomic classes among blacks suggest that socioeconomic status has a bigger impact on breastfeeding practices among blacks. Therefore, blacks, particularly those who are poor or less educated, need to be targeted for promotion, protection, and support of breastfeeding. (BIRTH 29:4 December 2002)
Home versus Hospital Breastfeeding Support for Newborns: A Randomized Controlled Trial
Authors: McKeever Patricia , Stevens Bonnie , Miller Karen‐Lee , MacDonell Jo Watson , Gibbins Sharyn , Guerriere Denise , Dunn Michael S. , Coyte Peter C. 
Published: February 2003

ABSTRACT: Background: The advantages of breastfeeding have been well established for both mothers and their infants. Existing research reports equivocal effects of early discharge and postpartum home care on breastfeeding success. The purpose of this study was to compare the effects of breastfeeding support offered in hospital and home settings on breastfeeding outcomes and maternal satisfaction for mothers of term and near‐term newborns who experienced standard or early discharge.Methods: In a randomized controlled trial with prognostic stratification for gestational age, 101 term and 37 near‐term (35–37 weeks’ gestational age) mother‐newborn pairs were randomized to either a standard care group (standard care and standard length of hospitalization) or an experimental group (standard hospital care with early discharge and home support from nurses who were certified lactation consultants). Data collection occurred before randomization, at discharge from hospital, and from 5 to12 days postpartum. Primary outcomes included breastfeeding rates and maternal satisfaction.Results: More mothers of term newborns in the experimental group were breastfeeding exclusively at follow‐up (p=0.02) compared with the control group. No significant breastfeeding differences occurred among mothers with near‐term newborns in the experimental and standard care groups.Conclusions: In‐home lactation support appears to facilitate positive breastfeeding outcomes for mothers of term newborns. This may also be a beneficial model of postpartum care for mothers of near‐term newborns; however, further research is required. The findings suggest implications for health caregivers and policy makers with respect to postpartum lactation and health care services. (BIRTH 29:4 December 2002)
Immigrant Women's Views About Care During Labor and Birth: An Australian Study of Vietnamese, Turkish, and Filipino Women
Authors: Small Rhonda , Yelland Jane , Lumley Judith , Brown Stephanie , Liamputtong Pranee 
Published: February 2003

ABSTRACT: Background: Few studies of immigrant women's views of maternity care in their new homelands have been conducted. In Victoria, Australia, approximately 1 woman in 7 giving birth was born overseas in a non‐English speaking country. This paper examines the views of three groups of immigrant women about the care they received in hospital for the birth of their babies and compares the findings with a population‐based statewide survey.Methods: Mothers in a New Country was a study of 318 Vietnamese, Turkish, and Filipino women interviewed about their maternity care experiences by bicultural interviewers 6 months after giving birth in Melbourne, Australia. The interview schedule was adapted from the 1994 Victorian Survey of Recent Mothers, a population‐based postal survey of 1336 women.Results: Of the 3 groups, 27 percent of Vietnamese, 48 percent of Turkish, and 39 percent of Filipino women reported their care during labor and birth as “very good,” figures significantly lower than for the statewide survey, in which 61 percent of women experiencing similar models of care described their care as “very good.” This significant differential in views about care was also present for many individual aspects of care. In the current study of mothers in a new country, comments about aspects of care with which women were particularly happy and unhappy highlighted their appreciation of care that was safe, kind, supportive, and respectful, and conversely, illustrated how distressed women were when care failed to meet these basic standards.Conclusions: What immigrant women wanted from their maternity care proved to be extremely similar to what Australian‐born women—and women the world over—want. Unfortunately, immigrant women were much less likely to experience care that gave them what they wanted. (BIRTH 29:4 December 2002)
Effect of Maternal Confidence on Breastfeeding Duration: An Application of Breastfeeding Self‐Efficacy Theory
Authors: Blyth Rosemary , Creedy Debra K. , Dennis Cindy‐Lee , Moyle Wendy , Pratt Jan , De Vries Susan M. 
Published: February 2003

ABSTRACT: Background: Although much research has focused on identifying factors that influence breastfeeding initiation and duration, many high‐risk factors are nonmodifiable demographic variables. Predisposing factors for low breastfeeding duration rates that are amenable to supportive interventions should be identified. The purpose of this study was to assess the effect of maternal confidence (breastfeeding self‐efficacy) on breastfeeding duration.Method: A prospective survey was conducted with 300 women in the last trimester of pregnancy recruited from the antenatal clinic of a large metropolitan hospital in Brisbane, Australia. Telephone interviews were conducted at 1week and 4 months postpartum to assess infant feeding methods and breastfeeding confidence using the Breastfeeding Self‐Efficacy Scale.Results: Although 92 percent of participants initiated breastfeeding, by 4 months postpartum almost 40 percent of mothers discontinued and only 28.6 percent were breastfeeding exclusively; the most common reason for discontinuation was insufficient milk supply. Antenatal and 1‐week Breastfeeding Self‐Efficacy Scale scores were significantly related to breastfeeding outcomes at 1 week and 4 months. Mothers with high breastfeeding self‐efficacy were significantly more likely to be breastfeeding, and doing so exclusively, at 1 week and 4 months postpartum than mothers with low breastfeeding self‐efficacy.Conclusions: Maternal breastfeeding self‐efficacy is a significant predictor of breastfeeding duration and level. Integrating self‐efficacy enhancing strategies may improve the quality of care that health care professionals deliver and may increase a new mother's confidence in her ability to breastfeed, and to persevere if she does encounter difficulties. (BIRTH 29:4 December 2002)
Barriers to Implementing the Group B Streptococcal Prevention Guidelines
Authors: Cárdenas Vicky , Davis Robert L. , Hasselquist Mary Beth , Zavitkovsky Ann , Schuchat Anne 
Published: February 2003

ABSTRACT: Background: Group B streptococcal disease is the leading cause of neonatal sepsis in the United States. We assessed predictors of compliance with the consensus guidelines for perinatal group B streptococcus disease prevention at two Group Health Cooperative hospitals.Methods: A descriptive and cohort analysis was conducted of failure to comply with the screening‐based approach to group B streptococcus prevention among singleton birth pregnancies in two Group Health Cooperative hospitals, September 1, 1996 to December 31, 1997. We studied determinants of failure to screen pregnant women for group B streptococcus at 35 to 37 weeks’ gestation and failure to deliver intrapartum antibiotic prophylaxis to Group B streptococcus‐positive women.Results: Nearly 28 percent of 1969 women delivering at two Group Health Cooperative hospitals were not screened appropriately for group B streptococcus. Women who were not screened properly were more likely to be in their teens. A short length of hospital stay before delivery was the strongest predictor of the lack of administration of intrapartum antibiotic prophylaxis to infected multiparas at delivery. Group B streptococcus‐positive women without pregnancy complications were less likely to receive intrapartum antibiotic prophylaxis than infected women with complications.Conclusions: The findings of this study suggest that to improve group B streptococcus disease prevention, screening efforts should focus on teenage women, and intrapartum antibiotic prophylaxis delivery efforts should be aimed at low‐risk women with precipitous labor. (BIRTH 29:4 December 2002)
Alignment-free sequence comparison—a review
Authors: Vinga Susana , Almeida Jonas 
Published: February 2003

Abstract
Motivation: Genetic recombination and, in particular, genetic shuffling are at odds with sequence comparison by alignment, which assumes conservation of contiguity between homologous segments. A variety of theoretical foundations are being used to derive alignment-free methods that overcome this limitation. The formulation of alternative metrics for dissimilarity between sequences and their algorithmic implementations are reviewed.
Results: The overwhelming majority of work on alignment-free sequence has taken place in the past two decades, with most reports published in the past 5 years. Two main categories of methods have been proposed—methods based on word (oligomer) frequency, and methods that do not require resolving the sequence with fixed word length segments. The first category is based on the statistics of word frequency, on the distances defined in a Cartesian space defined by the frequency vectors, and on the information content of frequency distribution. The second category includes the use of Kolmogorov complexity and Chaos Theory. Despite their low visibility, alignment-free metrics are in fact already widely used as pre-selection filters for alignment-based querying of large applications. Recent work is furthering their usage as a scale-independent methodology that is capable of recognizing homology when loss of contiguity is beyond the possibility of alignment.
Availability: Most of the alignment-free algorithms reviewed were implemented in MATLAB code and are available at http://bioinformatics.musc.edu/resources.html
Contact: almeidaj@musc.edu; svinga@itqb.unl.pt
* To whom correspondence should be addressed.
An information theoretic approach for analyzing temporal patterns of gene
expression
Authors: Kasturi Jyotsna , Acharya Raj , Ramanathan Murali 
Published: February 2003

Abstract
Motivation: Arrays allow measurements of the expression levels of thousands of mRNAs to be made simultaneously. The resulting data sets are information rich but require extensive mining to enhance their usefulness. Information theoretic methods are capable of assessing similarities and dissimilarities between data distributions and may be suited to the analysis of gene expression experiments. The purpose of this study was to investigate information theoretic data mining approaches to discover temporal patterns of gene expression from array-derived gene expression data.
Results: The Kullback–Leibler divergence, an information-theoretic distance that measures the relative dissimilarity between two data distribution profiles, was used in conjunction with an unsupervised self-organizing map algorithm. Two published, array-derived gene expression data sets were analyzed. The patterns obtained with the KL clustering method were found to be superior to those obtained with the hierarchical clustering algorithm using the Pearson correlation distance measure. The biological significance of the results was also examined.
Availability: Software code is available by request from the authors. All programs were written in ANSI C and Matlab (Mathworks Inc., Natick, MA).
Contact: jkasturi@cse.psu.eduacharya@cse.psu.edu
* To whom correspondence should be addressed.
Comparisons and validation of statistical clustering techniques for
microarray gene expression data
Authors: Datta Susmita , Datta Somnath 
Published: February 2003

Abstract
Motivation: With the advent of microarray chip technology, large data sets are emerging containing the simultaneous expression levels of thousands of genes at various time points during a biological process. Biologists are attempting to group genes based on the temporal pattern of their expression levels. While the use of hierarchical clustering (UPGMA) with correlation‘ distance’ has been the most common in the microarray studies, there are many more choices of clustering algorithms in pattern recognition and statistics literature. At the moment there do not seem to be any clear-cut guidelines regarding the choice of a clustering algorithm to be used for grouping genes based on their expression profiles.
Results: In this paper, we consider six clustering algorithms (of various flavors!) and evaluate their performances on a well-known publicly available microarray data set on sporulation of budding yeast and on two simulated data sets. Among other things, we formulate three reasonable validation strategies that can be used with any clustering algorithm when temporal observations or replications are present. We evaluate each of these six clustering methods with these validation measures. While the ‘best’ method is dependent on the exact validation strategy and the number of clusters to be used, overall Diana appears to be a solid performer. Interestingly, the performance of correlation-based hierarchical clustering and model-based clustering (another method that has been advocated by a number of researchers) appear to be on opposite extremes, depending on what validation measure one employs. Next it is shown that the group means produced by Diana are the closest and those produced by UPGMA are the farthest from a model profile based on a set of hand-picked genes.
Availability: S+ codes for the partial least squares based clustering are available from the authors upon request. All other clustering methods considered have S+ implementation in the library MASS. S+ codes for calculating the validation measures are available from the authors upon request. The sporulation data set is publicly available at http://cmgm.stanford.edu/pbrown/sporulation
Supplementary information: http://www.mathstat.gsu.edu/~matsnd/clustering/supp.htm
Contact: sdatta@mathstat.gsu.edu
* To whom correspondence should be addressed.
Survey of Continuities of Curves and Surfaces
Authors: Veltkamp Remco C. 
Published: February 2003

AbstractThis survey presents an overview to various types of continuity of curves and surfaces, in particular parametric (Cn), visual or geometric (Cn, Gn), Frenet frame (Fn), and tangent surface continuity (Tn), and discusses the relation with curve and surface modeling, visibility of (dis) continuities, and graphics rendering algorithms. It is the purpose of this paper to provide an overview of types of continuity, and to put many terms and definitions on a common footing in order to give an understanding of the subject.1991 Computing Reviews Classification:I.3.5 [Computer Graphics] Computational geometry and object modeling.I.3.7 [Computer Graphics] Three‐Dimensional Graphics and Realism.
User Interface Management Systems for Engineering Applications
Authors: Sastry Lakshmi 
Published: February 2003

AbstractEssential features of a User Interface Management System (UIMS) from the perspective of engineering applications' user interface development are described. Three commercially available UIMS are validated against this set of essential features and the results of such a categorised evaluation are reported. The proliferation of user interface design tools necessitated an initialfiltering to select these tools on the basis of their availability on a wide range of platforms currently used by engineers, supplier support for the product and the prototyping tools the UIMS offer. Graphic Modelling System (GMS), TeleUSE and USEIT were selected for their potential utility to engineering applications.An earlier version of this paper was presented at the 1991 European X User Group Annual Conference held at Queens' College, Cambridge, UK.This comparative evaluation is compiled on behalf of the UK Science and Engineering Research Council, for the benefit of the UK academic engineering research community.
A Statistical Comparison of Two Hidden Surface Techniques: the Scan‐line and Z‐buffer Algorithms
Authors: Slater Mel , Drake Kieron , Davison Allan , Kordakis Emmanouell , Billyard Adam , Miranda Eliot 
Published: February 2003

AbstractThis paper compares two image space hidden surface removal algorithms for polygonal scenes. These are the z‐buffer and scan‐line algorithms. There is first an overview of each algorithm, followed by a simulation experiment, designed to compare the number of polygons per second which can be rendered by each algorithm. The simulation varies the number of polygons in the scene, and the size and distribution of polygons over the display. The results suggest that the z‐buffer is preferred for a large enough number of polygons, however, smaller polygons and uniform distribution of polygons favour the scan‐line approach. The analysis does not take into account the complexity of the shading rule, which is likely also to favour the scan‐line method.
Integer de Casteljau Algorithm for Rasterizing NURBS Curves
Authors: Anantakrishnan Narayanan , Piegl Les A. 
Published: February 2003

AbstractAn integer version of the well‐known de Casteljau algorithm of NURBS curves is presented here. The algorithm is used to render NURBS curves of any degree on a raster device by turning on pixels that are closest to the curve. The approximation is independent of the parametrization, that is, it is independent of the weights used. The algorithm works entirely in the screen coordinate system and produces smooth rendering of curves without oversampling. Because of the integer arithmetic used, the algorithm is easily cast in hardware.
Ray Coherence Between a Sphere and a Convex Polyhedron
Authors: Horvath Tamas , Marton Gabor , Risztics Peter , Szirmay‐Kalos Laszlo 
Published: February 2003

AbstractUsing the two ray coherence theorems of Ohta and Maekawa the computation time of ray tracing algorithms for scenes of spheres and convex polyhedra can be reduced considerably. This paper presents further theorems which, together with the first two, may enable further reduction in computation time.
Requirement of the Adenovirus IVa2 Protein for Virus Assembly
Authors: Zhang Wei , Imperiale Michael J. 
Published: February 2003

ABSTRACT

The adenovirus L1 52/55-kDa protein is required for viral DNA packaging and interacts with the viral IVa2 protein, which binds to the viral packaging sequence. Previous reports suggest that the IVa2 protein plays a role in viral DNA packaging and that this function of the IVa2 protein is serotype specific. To further examine the function of the IVa2 protein in viral DNA packaging, a mutant virus that does not express the IVa2 protein was constructed by introducing two stop codons at the beginning of the IVa2 open reading frame in a full-length bacterial clone of adenovirus type 5. The mutant virus,
pm
8002, was defective for growth in 293 cells, although it replicated its DNA and produced early and late viral proteins. Electron microscopic and gradient analyses revealed that the mutant virus did not assemble any viral particles in 293 cells. In 293-IVa2 cells, which express the IVa2 protein, infectious viruses were produced, although the titer of the mutant virus was lower than that of the wild-type virus, indicating that these cells may not fully complement the mutation. The mutant viral particles produced in 293-IVa2 cells were heterogeneous in size and shape, less stable, and did not traffic efficiently to the nucleus. Marker rescue experiments with a wild-type IVa2 DNA fragment confirmed that the only mutations present in
pm
8002 were in the IVa2 gene. The results indicate that the IVa2 protein is required for adenovirus assembly and suggest that virus particles may be assembled around the DNA rather than DNA being packaged into preformed capsids.