bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk of Infant Mortality Among Twins in Relation to Placental Abruption: Contributions of Preterm Birth and Restricted Fetal Growth
Authors: Ananth Cande V. , Smulian John C. , Srinivas Neela , Getahun Darios , Salihu Hamisu M. 
Published: May 2007

AbstractWhile preterm birth and restricted fetal growth are strongly associated with infant mortality, the extent to which these associations are modified by placental abruption remains unknown. A retrospective cohort study was carried out to examine the risk of infant mortality among twins in relation to abruption, and explore the independent contributions of preterm birth and restricted fetal growth to these associations. The study was restricted to women who had delivered twins at 22 weeks' gestation or more and fetuses weighing 500 grams or more in the United States (1989–2000). Risks of preterm birth (less than 37 weeks' gestation), fetal growth restriction and infant mortality, in relation to placental abruption, were evaluated. All analyses were adjusted for potential sociodemographic confounding factors. The association between restricted twin fetal growth and abruption was the strongest among the most severely growth-restricted babies (i.e., less than 1 centile), with the strength of association diminishing with increasing birthweight centiles. The risk of preterm birth among pregnancies with and without abruption were 80.1% and 51.9%, respectively (relative risk [RR] 1.5, 95% confidence interval [CI] 1.4–1.6). The risk of small-for-gestational-age (SGA; birthweight of less than the 10th centile for gestational age) among abruption and nonabruption births was 11.7% and 9.2%, respectively (RR 1.3, 95% CI 1.2–1.4). Compared with twins of the appropriate growth delivered at term, the relative risks for infant mortality in the presence of abruption were 9.9 (95% CI 5.4–18.2) for term-SGA, 25.0 (95% CI 22.3–28.1) for preterm-non-SGA, and 36.2 (95% CI 28.4–46.1) for preterm-SGA births. The association between infant mortality and abruption among twins appears largely mediated through preterm birth, and to a lesser extent, through SGA. The association between fetal growth and abruption is strongest among the severely growth-restricted babies, suggesting that the origins of placental abruption may develop in early pregnancy.
Causal Hypothesis for Some Congenital Anomalies
Authors: Pharoah Peter O. D. 
Published: May 2007

AbstractCongenital anomalies are a major cause of fetal and neonatal death and of childhood morbidity. Chromosomal and other genetic abnormalities, environmental teratogens and some nutritional deficiencies account for some congenital anomalies but the majority are of unknown etiology. The hypothesis is here proposed that a significant proportion of congenital anomalies and cerebral palsy of unknown etiology are attributable to a monozygotic multiple conception with monochorionic placentation and that these anomalies, even in singletons, may be explained by early, unrecognized or unrecorded loss of one conceptus in a monochorionic monozygotic conception. The pathological mechanism is hemodynamic instability with episodes of acute feto–fetal transfusion that produce ischemic organ impairment in either or both twins. The resultant clinical abnormality will depend on range of severity (fetal death, infant death, congenital anomaly, normal infant), site or combination of sites (which organ[s] present[s] with the congenital anomaly) and timing (early, middle or late in gestation as shown by variation in brain pathology that is observed).
Problems With Using Sum Scores for Estimating Variance Components: Contamination and Measurement Noninvariance
Authors: Neale Michael C. , Lubke Gitta , Aggen Steven H. , Dolan Conor V. 
Published: May 2007

AbstractTwin studies of complex traits, such as behavior or psychiatric diagnoses, frequently involve univariate analysis of a sum score derived from multiple items. In this article, we show that absence of measurement invariance across zygosity can bias estimates of genetic and environmental components of variance. Specifically, if the item responses are considered as multiple indicators of a latent factor, and the aim is to partition the variance in the latent factor, then the factor loadings relating the items to the factor should be equal for monozygotic (MZ) and dizygotic (DZ) twins. While it seems unlikely, a priori, that these loadings should differ as a function of zygosity, certain special measurement situations are cause for concern. Ratings by parents, or self-ratings of pheno- types which are more easily observed in others than via introspection, may be tainted by the co-twin's phenotype to a greater extent in MZ than DZ pairs. We also show that the analysis of sum scores typically biases both MZ and DZ correlations compared to the true latent trait correlation. These two sources of bias are quantified for a range of values and are shown to be especially acute for sum scores based on binary items. Solutions to these problems include formal tests for measurement invariance across zygosity prior to analysis of the sum or scale scores, and multivariate genetic analysis at the individual item or symptom level.
Parameterization of Sex-Limited Autosomal Linkage Analysis for Mx
Authors: Medland Sarah E. 
Published: May 2007

AbstractIncorporation of sex-limitation (genotype-sex interaction) effects into a model of quantitative trait loci (QTL) analysis has been shown to increase the power to detect linkage when analyzing traits in which sex limitation is present (Towne et al., 1997). The present note provides a parameterization of the nonscalar sex-limitation ACE model incorporating autosomal sex-limited QTL effects for use with the Mx matrix algebra program (Neale et al., 2002). An example script designed for use with extended sib- ships that takes advantage of the versatile treatment of covariates within Mx is included.
The Etiology of Mathematical and Reading (Dis)ability Covariation in a Sample of Dutch Twins
Authors: Markowitz Ezra M. , Willemsen Gonneke , Trumbetta Susan L. , van Beijsterveldt Toos C. E. M. , Boomsma Dorret I. 
Published: May 2007

AbstractThe genetic etiology of mathematical and reading (dis)ability has been studied in a number of distinct samples, but the true nature of the relationship between the two remains unclear. Data from the Netherlands Twin Register was used to determine the etiology of the relationship between mathematical and reading (dis)ability in adolescent twins. Ratings of mathematical and reading problems were obtained from parents of over 1500 twin pairs. Results of bivariate structural equation modeling showed a genetic correlation around .60, which explained over 90% of the phenotypic correlation between mathematical and reading ability. The genetic model was the same for males and females.
Sex-Limited Genome-Wide Linkage Scan for Body Mass Index in an Unselected Sample of 933 Australian Twin Families
Authors: Cornes Belinda K. , Medland Sarah E. , Ferreira Manuel A. R. , Morley Katherine I. , Duffy David L. , Heijmans Bastiaan T. , Montgomery Grant W. , Martin Nicholas G. 
Published: May 2007

AbstractGenes involved in pathways regulating body weight may operate differently in men and women. To determine whether sex-limited genes influence the obesity-related phenotype body mass index (BMI), we have conducted a general non- scalar sex-limited genome-wide linkage scan using variance components analysis in Mx (Neale, 2002). BMI measurements and genotypic data were available for 2053 Australian female and male adult twins and their siblings from 933 families. Clinical measures of BMI were available for 64.4% of these individuals, while only self-reported measures were available for the remaining participants. The mean age of participants was 39.0 years of age (SD 12.1 years). The use of a sex-limited linkage model identified areas on the genome where quantitative trait loci (QTL) effects differ between the sexes, particularly on chromosome 8 and 20, providing us with evidence that some of the genes responsible for BMI may have different effects in men and women. Our highest linkage peak was observed at 12q24 (–log10p = 3.02), which was near the recommended threshold for suggestive linkage (–log10p = 3.13). Previous studies have found evidence for a quantitative trait locus on 12q24 affecting BMI in a wide range of populations, and candidate genes for non- insulin-dependent diabetes mellitus, a consequence of obesity, have also been mapped to this region. We also identified many peaks near a –log10p of 2 (threshold for replicating an existing finding) in many areas across the genome that are within regions previously identified by other studies, as well as in locations that harbor genes known to influence weight regulation.
Association Between Dopamine D4 Receptor Exon III Polymorphism and Emotional Reactivity as a Temperamental Trait
Authors: Oniszczenko Wlodzimierz , Dragan Wojciech L. 
Published: May 2007

AbstractThe association between high and low levels of emotional reactivity (ER) as a temperamental trait and the dopamine D4 receptor (DRD4) exon III polymorphism in healthy men aged 18 to 27 (M= 21.03,SD= 2.23) was examined. ER, measured by the Formal Characteristics of Behavior–Temperament Inventory (FCB-TI), is defined as a tendency to react intensively to emotion-generating stimuli and is expressed in high emotional sensitivity and in low emotional endurance. Data analysis demonstrated a statistically significant difference in the distribution of genotypic frequencies between the low and high ER groups:χ2= 4.88;df= 1;p= .027, odds ratio (OR) =2.85, 95% confidence interval (CI) = 1.11–7.32. An insignificant difference in allele frequencies between the two groups was noted:χ2= 7.47;df= 3;p= .058; OR = 2.9, 95% CI = 1.29–6.53. These findings suggest a role of the DRD4 exon III polymorphism in the modulation of ER as a temperamental trait. Due to the preliminary nature of our findings, replication is necessary.
Temperature-Mediated Differences in Bacterial Kidney Disease Expression and Survival in Renibacterium salmoninarum-challenged Bull Trout and Other Salmonids
Authors: Jones Darin T. , Moffitt Christine M. , Peters K. Kenneth 
Published: May 2007

Abstract
Resource managers considering restoration and reconnection of watersheds to protect and enhance threatened populations of bull trout Salvelinus confluentus have little information about the consequences of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum. To better understand the response of bull trout to R. salmoninarum challenge, we conducted several laboratory experiments at two water temperatures. The extent, severity, and lethality of BKD in bull trout were compared with those of similarly challenged lake trout S. namaycush, Arctic char S. alpinus, Chinook salmon Oncorhynchus tshawytscha, and rainbow trout O. mykiss. The lethal dose of bacterial cells necessary to induce 50% mortality (LD50) was 10-fold lower at the 15°C challenge than at the 9°C challenge. Of the species tested, bull trout were relatively resistant to BKD, Arctic char were the most susceptible among Salvelinus species, and Chinook salmon were the most susceptible among Oncorhynchus species tested. Mean time to death was more rapid for all fish tested at 15°C than for fish challenged at 9°C. These results suggest that infection of bull trout with BKD likely poses a low risk to successful restoration of threatened populations.
Seasonal Natural and Fishing Mortality of Striped Bass in a Southeastern Reservoir
Authors: Thompson Jessica S. , Waters D. Scott , Rice James A. , Hightower Joseph E. 
Published: May 2007

Abstract
Reliable estimates of natural and fishing mortality are important for management of exploited fish populations, but these components of the total mortality rate can be difficult to determine by traditional fisheries methods. We used telemetry data to determine seasonal instantaneous fishing (F) and natural mortality (M) rates of subadult and adult striped bass Morone saxatilis in Badin Lake, North Carolina. Our analyses were based on the fates of 64 fish implanted with sonic transmitters and released and tracked for 2 years. Natural mortality was low and constant during the course of the study (M ± SE = 0.10 ± 0.01) and was similar to estimates for other reservoir populations of striped bass. A natural mortality rate of 0.09–0.16 may be a reasonable approximation for populations across the southeastern United States. Fishing mortality varied seasonally and was highest in the spring and summer of 2002 and the summer and fall of 2003; annual fishing mortality (F ± SE) was 0.65 ± 0.08 in 2002 and 0.77 ± 0.08 in 2003. Due to these high harvest rates, estimated annual survival rates were low for the Badin Lake population (47% in 2002; 42% in 2003). Results of a yield-per-recruit model suggest that harvest of older, larger individuals can be increased in Badin Lake with a decrease in fishing mortality or a moderate increase in the minimum size limit, even when the effect of catch-and-release mortality of fish below the size limit is considered. Our results also indicate important considerations for researchers using this method in the future, including the need to estimate downstream emigration and delay the inclusion of newly tagged fish in analysis to avoid biasing estimates of fishing mortality.
Evaluating Creel Survey Efficiency for Estimating Walleye Fishery Metrics in Northern Wisconsin Lakes
Authors: Deroba Jonathan J. , Hansen Michael J. , Nate Nancy A. , Hennessy Joseph M. 
Published: May 2007

Abstract
To determine whether creel survey efficiency can be improved in northern Wisconsin lakes, we compared estimates of effort, harvest rate, harvest, recapture rate for previously marked fish (R/C ratio), and recaptures of walleyes Sander vitreus from four reduced-sampling-effort schemes (eliminating 1 week per month, 2 weeks per month, odd-numbered weeks, and even-numbered weeks) in each month of the angling season with estimates from creel surveys during 1991–2002. Estimates of angler-hours from each reduced-sampling-effort scheme differed significantly from those from the full sampling effort in several months, and variances differed significantly in nearly all months. Estimates of walleyes harvested per hour from each reduced-sampling-effort scheme differed significantly from those from the full sampling effort only in May or June, and variances differed significantly in several months for all sampling effort schemes except that of 1 week per month. Estimates of walleye harvest from all reduced-sampling-effort schemes differed significantly from those from the full sampling effort for at most 2 months, but variances did not differ significantly in several months. Estimates of the R/C ratio from all reduced-sampling-effort schemes differed significantly from those from the full sampling effort for at most 2 months, but variances differed significantly in several months. Estimates of the number of recaptures differed significantly from those from the full sampling effort for several months with the elimination of 1 week per month and 2 weeks per month but did not differ significantly with the elimination of odd- or even-numbered weeks, and variances differed significantly in several months for all reduced-sampling-effort schemes. Creel survey efficiency cannot be improved using these sampling effort reductions without causing significant losses in accuracy and precision.
The effects of alcohol and the salience of aggressive cues on triggered displaced aggression
Authors: Denson Thomas F. , Aviles Fredy E. , Pollock Vicki E. , Earleywine Mitch , Vasquez Eduardo A. , Miller Norman 
Published: May 2007

AbstractAlcohol increases the aggression‐augmenting effects of provocation. Theories of alcohol and aggression suggest that impaired cognitive processing induced by acute intoxication leads individuals to process aggression‐inducing social cues differently depending on whether they are high or low in salience. We examined the effects of intoxication and aggressive cue salience within the triggered displaced aggression paradigm. An ethnically diverse sample of 74 primarily young adult participants (40 men and 34 women; M=23.28, SD=3.14 years) were recruited from the university community and surrounding area. All participants were provoked by an experimenter, randomly assigned to a 2 (alcohol condition: alcohol vs. placebo) × 2 (trigger salience: high vs. low salience) between‐subjects design, and then given the opportunity to aggress against the undeserving triggering agent. As expected, intoxication combined with a salient triggering cue elicited the most displaced aggression among all conditions. These results provide the first evidence that the effect of alcohol on triggered displaced aggression is moderated by the salience of the triggering event. Aggr. Behav. 34:25–33, 2008. © 2007 Wiley‐Liss, Inc.
The geometry of separation boundaries: Four‐component mixtures
Authors: Bellows Meghan , Lucia Angelo 
Published: May 2007

AbstractThe determination of distillation boundaries for four‐component mixtures that exhibit azeotropy is studied. It is shown that these distillation boundaries correspond to local maxima in surface areas under conditions of Levi‐Civita parallelism. An extension of the optimization methodology given in Lucia and Taylor is used to determine local maxima in surface areas by repeatedly computing maximum line integrals or distances in one spherical coordinate over a set of initial conditions that span the range of the second spherical coordinate. An optimization formulation that defines the determination of local maxima in surface areas subject to residue curve and stable node constraints is given. Numerical measurement of surface areas is accomplished using a triangulation procedure. Several numerical examples of varying complexity involving four‐component mixtures that exhibit azeotropes are presented to show the efficacy of the proposed optimization methodology. Geometric illustrations are used throughout to highlight key features of our methodology for determining distillation boundaries in four‐component mixtures. © 2007 American Institute of Chemical Engineers AIChE J, 2007
Compressible cake characterization from steady‐state filtration analysis
Authors: Kovalsky Peter , Gedrat Marion , Bushell Graeme , Waite T. David 
Published: May 2007

AbstractA numerical technique for quantifying the key material properties that describe how a flocculated suspension behaves under constant pressure filtration is presented with unrestricted compressive yield stress and permeability models used to describe these material properties. Using an iterative procedure, the optimal parameters for these models are calculated as are pressure and solid fraction distribution profiles. Input parameters to the numerical analysis are flux and final cake height data obtained from batch filtration experiments, which are driven to steady‐state. This technique is validated against piston driven filtration (odeometer) and centrifuge experiments for zirconia, soil particles, and yeast assemblages. The compressive yield stress calculated from filtration experiments agrees well with values obtained by odeometer and centrifuge studies for all particle systems studied at both the low and high solid pressure regions. Similarly, the calculated permeability agrees well with the measured permeability. © 2007 American Institute of Chemical Engineers AIChE J, 2007
The politics of lead toxicology and the devastating consequences for children
Authors: Rosner David , Markowitz Gerald 
Published: May 2007

AbstractAt virtually every step in the history of the uncovering of lead's toxic qualities, resistance was shown by a variety of industrial interests to the association of lead and toxicity. During the first half of the last century, three primary means were used to undermine the growing body of evidence: first, the lead industry sought to control lead research by sponsoring and funding university research. In the 1920s, the General Motors Company, with the aide of DuPont and Standard Oil Companies, established the Kettering Labs, a research unit at the University of Cincinnati which, for many decades was largely supported by industry funds. In the same decade, the lead industry sponsored the research of Joseph Aub at Harvard who worked on neurophysiology of lead. A second way was to shape our understanding of lead itself, portraying it as an indispensable and healthful element essential for all modern life. Lead was portrayed as safe for children to use, be around, and even touch. The third way that lead was exempted from the normal public health measures and regulatory apparatus that had largely controlled phosphorus poisoning, poor quality food and meats and other potential public health hazards was more insidious and involved directly influencing the scientific integrity of the clinical observations and research. Throughout the past century tremendous pressure by the lead industry itself was brought to bear to quiet, even intimidate, researchers and clinicians who reported on or identified lead as a hazard. This article will draw on our previous work and add new documentation of the trajectory of industry attempts to keep out of the public view the tremendous threat of lead poisoning to children. Am. J. Ind. Med. 50:740–756, 2007. © 2007 Wiley‐Liss, Inc.
The 19‐bp deletion polymorphism in intron‐1 of dihydrofolate reductase (DHFR) may decrease rather than increase risk for spina bifida in the Irish population
Authors: Parle‐McDermott Anne , Pangilinan Faith , Mills James L. , Kirke Peadar N. , Gibney Eileen R. , Troendle James , O'Leary Valerie B. , Molloy Anne M. , Conley Mary , Scott John M. , Brody Lawrence C. 
Published: May 2007

AbstractPericonceptional maternal folic acid supplementation can prevent up to 70% of pregnancies affected with neural tube defects (NTDs), including spina bifida. This has focused attention on folate‐related genes such as dihydrofolate reductase (DHFR) in a bid to identify the genetic factors that influence NTD risk through either the fetal or maternal genotype. We considered a novel intronic 19‐bp deletion polymorphism and two polymorphisms within the 3′ untranslated region (721A > T and 829C > T) of the DHFR gene as candidates for NTD risk. We studied NTD cases (n = 283), mothers of cases (n = 280), fathers of cases (n = 279), and controls (n = 256). We did not find the DHFR 829C > T polymorphism to be variable within the Irish population. The 19‐bp intron deletion and the 721A > T polymorphisms were found to be in linkage disequilibrium. In contrast to a previous study, the 19‐bp intron deletion allele did show a significant protective effect in mothers of NTD cases when present in one (relative risk 0.59 [95%CI: 0.39–0.89], P = 0.01) or two copies (relative risk 0.52 [95%CI: 0.32–0.86], P = 0.01). Analysis of mRNA levels revealed a small increase in expression (∼1.5‐fold) associated with the 19‐bp intron deletion polymorphism, but this was not significant. In conclusion, the DHFR intron 19‐bp deletion allele may be a protective NTD genetic factor by increasing DHFR mRNA levels in pregnant women. © 2007 Wiley‐Liss, Inc.