bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time trends in twin perinatal mortality in northern England, 1982–94
Authors: Glinianaia Svetlana V , Rankin Judith , Renwick Marjorie ,   on behalf of the Northern Region Perinatal Mortality Survey Steering Group
Published: March 2007

AbstractThe dynamics of perinatal mortality rates (PNMR) and causes of death in twin pregnancies over 13 years in the Northern Region of the National Health Service in England is described. All twin perinatal deaths occurring between 1982–1994 were identified from the Northern Region Perinatal Mortality Survey. The twinning rate increased from 9.9 per 1000 maternities in 1982 to 12.0 in 1994. There was a total of 10734 twin pregnancies and of these 421 resulted in 530 perinatal deaths. The perinatal mortality rate in twins significantly decreased over time (1982–87, 55.4 per 1000; 1988–94, 44.4 per 1000; P = 0.01). The PNMR was significantly higher for twins from like-sexed than from unlike-sexed pairs (53.5 and 34.4 per 1000 respectively, P < 0.001). Despite no improvement in birthweight distribution in the twin population, birthweight-specific perinatal mortality rates for both like and unlike-sexed twins decreased for each birthweight category in 1988–94 compared with 1982–87. Twins with very low birthweight ( < 1500 g) comprised 69%, and preterm twins ( < 37 completed weeks of gestation) 74.9% of all twin perinatal deaths. The major immediate cause of early neonatal death was pulmonary immaturity (63%); antepartum anoxia caused 76.9% of antenatal deaths. Unexplained preterm labour and intrauterine death were the leading obstetric factors underlying death in twins. Despite a decrease over the 13 years, the perinatal mortality rate in twins in the Northern Region remains high. Continued monitoring of trends in twinning and mortality rates is needed to inform health care planning.
Maternal smoking and twinning
Authors: Källén Karin 
Published: March 2007

AbstractIn order to investigate a possible association between maternal smoking during pregnancy and twinning, information on 1 096 330 single births and 12 342 twin births in 1983–95 was obtained from the Swedish Medical Birth Registry (MBR). All odds ratios (OR) were estimated after stratification for year of birth and maternal age, parity, and educational level. Smoking women, compared with non-smoking women, were at increased risk of having dizygotic (DZ) twins, but the risk increase was only evident among multiparas. A strong association between previous involuntary childlessness and dizygotic (DZ) twinning (especially in primiparas) was found. The strongest association between maternal smoking and DZ twinning was found among multiparas without any history of involuntary childlessness (OR: 1.35, 95%CI:1.22–1.49), whereas among women who had experienced involuntary childlessness, the opposite was seen (OR: 0.82, 95%CI:0.66–1.00, no difference between parity strata). Weinberg's differential method was used to estimate the number of monozygotic (MZ) twins, and a method of estimating stratified ORs among mothers of MZ twins was presented. No association was found between MZ twinning and maternal smoking (OR: 0.96, 95%CI:0.86–1.07), and no confounding by parity or previous involuntary childlessness was indicated. Several non-causal explanations to the positive association between DZ twinning and maternal smoking among multiparas were discussed, but homogeneity over strata indicated that maternal smoking may be a true risk factor for double ovulation.
No paternal effect on monozygotic twinning in the Swedish Twin Registry
Authors: Lichtenstein Paul , Källén Bengt , Köster Max 
Published: March 2007

AbstractPrevious research has provided evidence for a genetic effect in monozygotic twinning, indicated by an increased risk for monozygotic women to have monozygotic offspring. However, since the biological mechanism for this trait is unknown, it is not clear if there exists a paternal inheritance. In this study we investigated twin pregnancies in offspring born in 1941–1996 to male twins in the Swedish Twin Registry and population controls born in 1926–1980. In total 4 225 331 offspring, of which 89 286 were twins, were studied. There was neither an increase in the probability for monozygotic men to have like-sexed twin offspring risk ratio (RR = 0.95; 95% CI = 0.77–1.13) nor an increase in the estimated number of monozygotic twin births. Thus, there is no evidence for a paternal effect on monozygotic twinning, suggesting that the gene(s) increasing the liability for division of the embryo are expressed in the mother and not in the fertilised egg.
Nature vs nurture: Are leaders born or made? A behavior genetic investigation of leadership style
Authors: Johnson Andrew M , Vernon Philip A , McCarthy Julie M , Molson Mindy , Harris Julie A , Jang Kerry L 
Published: March 2007

AbstractWith the recent resurgence in popularity of trait theories of leadership, it is timely to consider the genetic determination of the multiple factors comprising the leadership construct. Individual differences in personality traits have been found to be moderately to highly heritable, and so it follows that if there are reliable personality trait differences between leaders and non-leaders, then there may be a heritable component to these individual differences. Despite this connection between leadership and personality traits, however, there are no studies of the genetic basis of leadership using modern behavior genetic methodology. The present study proposes to address the lack of research in this area by examining the heritability of leadership style, as measured by self-report psychometric inventories. The Multifactor Leadership Questionnaire (MLQ), the Leadership Ability Evaluation, and the Adjective Checklist were completed by 247 adult twin pairs (183 monozygotic and 64 same-sex dizygotic). Results indicated that most of the leadership dimensions examined in this study are heritable, as are two higher level factors (resembling transactional and transformational leadership)derived from anobliquely rotated principal components factors analysis of the MLQ. Univariate analyses suggested that 48% of the variance in transactional leadership may be explained by additive heritability, and 59% of the variance in transformational leadership may be explained by non-additive (dominance) heritability. Multi-variate analyses indicatedthat most ofthe variables studiedshared substantial genetic covariance, suggesting a large overlap in the underlying genes responsible for the leadership dimensions.
Book Reviews
Authors: Baumgarten Linda 
Published: March 2007

American Artifacts of Personal Adornment, 1680‐1820 by Carolyn L. White. Lanham, MD: AltaMira Press, 2005. 160 pp.Linda Baumgarten is Curator of Textiles and Costumes at the Colonial Williamsburg Foundation where she has worked since 1978. She is the author of What Clothes Reveal: The Language of Clothing in Colonial and Federal America (Yale University Press, 2002) and (with John Watson) Costume Close‐Up: Clothing Construction and Pattern, 1750–1790 (Quite Specific Media Group, 2000).
Book Reviews
Authors: Arnoldi Mary Jo 
Published: March 2007

Unwrapping the Textile Traditions of Madagascar by Chapurukha M. Kusimba, J. Claire Odland, and Bennet Bronson, eds. Los Angeles: Fowler Museum of Cultural History, 2004. 196 pp. (Co‐published with the Field Museum.)Mary Jo Arnoldi is a curator for African ethnology and arts in the Department of Anthropology, National Museum of Natural History. She is the author of Playing with Time: Art and Performance in Central Mali (Indiana University Press, 1995) and was the lead curator on the permanent exhibition African Voices that opened at the Smithsonian in 1999.
Declines in Low Birth Weight and Preterm Birth Among Infants Who Were Born to HIV-Infected Women During an Era of Increased Use of Maternal Antiretroviral Drugs: Pediatric Spectrum of HIV Disease, 1989–2004
Authors: Schulte Joann , Dominguez Ken , Sukalac Thomas , Bohannon Beverly , Fowler Mary Glenn ,   for the Pediatric Spectrum of HIV Disease Consortium
Published: March 2007

OBJECTIVE. Our goal was to determine trends in low birth weight and preterm birth among US infants born to HIV-infected women.METHODS. We used data from the longitudinal Pediatric Spectrum of HIV Disease, a large HIV cohort, to assess trends in low birth weight and preterm birth from 1989 to 2004 among 11321 study infants. Among women with prenatal care, we also assessed risk factors, including maternal antiretroviral therapy during pregnancy, that were predictive of low birth weight and preterm birth using univariate and multivariate logistic regression models.RESULTS. Overall, 11231 of 14464 infants who were enrolled in Pediatric Spectrum of HIV Disease were tested during the neonatal period. From 1989 to 2004, testing increased from 32% to 97%. The proportion of HIV-exposed infants who had low birth weight decreased from 35% to 21% and occurred in all racial/ethnic groups. Prevalence of preterm birth decreased from 35% to 22% and occurred in all groups. Any maternal antiretroviral therapy use increased from 2% to 84%. Among 8793 women who had prenatal care, low birth weight was associated with a history of illicit maternal drug use, unknown maternal HIV status before delivery, symptomatic maternal HIV disease, black race, Hispanic ethnicity, and infant HIV infection. Antiretroviral therapy or lack of it was not associated with low birth weight. Among women with prenatal care, preterm birth was associated with a history of illicit maternal drug use, symptomatic maternal HIV disease, no antiretroviral therapy, receipt of a 3-drug highly active antiretroviral therapy regimen with protease inhibitors, black race, and infant HIV infection.CONCLUSIONS. The proportion of infants who had low birth weight or were born preterm declined during an era of increased maternal antiretroviral therapies. These Pediatric Spectrum of HIV Disease trends differ from the overall increases in both outcomes among the US population.
Efficacy of a Pill-Swallowing Training Intervention to Improve Antiretroviral Medication Adherence in Pediatric Patients With HIV/AIDS
Authors: Garvie Patricia A. , Lensing Shelly , Rai Shesh N. 
Published: March 2007

OBJECTIVE. We aimed to retrospectively assess the efficacy of pill-swallowing training provided as a clinical intervention to referred pediatric patients with HIV in relation to improved adherence and subsequent related health outcomes. The primary goal of this study was to demonstrate participation in pill-swallowing training is associated with improved medication adherence as documented by routine pharmacy pill counts. Secondary objectives were to assess corresponding improvements in clinically observed biologic indicators of adherence, specifically, immunologic functioning (CD4+ T-cell%) and viral load, over time.
PATIENTS AND METHODS. A retrospective chart review of 23 pediatric patients with HIV aged 4 to 21 years who were clinically referred for pill-swallowing training by an experienced pediatric psychologist for either noted difficulties with currently prescribed antiretroviral regimens and/or desire to change the child's regimen/formulary. Patient demographics, reason(s) for pill-swallowing training referral, number of pill-swallowing training sessions required to attain success, adherence, CD4+ T-cell%, and viral load were abstracted at baseline and at ∼3 and 6 months posttraining.
RESULTS. Modal number of sessions required to acquire the pill-swallowing skill was 1 session. Younger children (aged 4–5 years) required a median of 2 training sessions, while older children required ≥3 sessions. A significant improvement in adherence from baseline to 6 months post–pill-swallowing training completion was observed, as were significant related improvements in CD4+ T-cell% and viral load.
CONCLUSIONS. Participation in pill-swallowing training related to improved medication adherence at 6 months posttraining. Subsequent improvements in related CD4+ T-cell% and viral load were noted over time, most significantly at 6 months postintervention. These preliminary findings provide justification for additional study via a prospective, randomized, controlled clinical trial. Pill-swallowing training potentially is a successful time-limited, cost-effective intervention to improve adherence to antiretroviral therapies, and thus medical status, in children with HIV.
Influence of tamper weight shape on dynamic compaction
Authors: Arslan H. , Baykal G. , Ertas O. 
Published: March 2007

This paper presents the effect of tamper weight shape on the dynamic compaction method in granular soils. Although the dynamic compaction method appears to be very simple, it requires careful design of the compaction process. The aim of this study is to improve the efficiency and decrease the cost of deep compaction by using cylinder-shaped tamper weights. The influence of the shape of the bottom of the tamper weight on dynamic compaction efficiency was evaluated experimentally on sandy soils. Sands of three different densities were used to evaluate the compaction efficiency. Conical-bottom tamper weights were studied with the conic angle approximately the same values as the internal friction angles of the three different densities of soil. Also, in order to compare results, a flat-bottom tamper was used with the same weight. The results indicated significant increases of the amount of ground improvement by using a conical rather than a flat-bottom load. Cet article traite de l'effet de la forme du poids de dameuse sur la méthode de compactage dynamique sur les sols granulaires. Bien que cette méthode apparaisse très simple, elle demande une conception soignée du processus de compactage. Cette étude a pour objectif d'améliorer l'efficacité et de réduire le coût du compactage profond en utilisant des poids de dameuse de forme cylindrique. Elle évalue expérimentalement l'influence de la forme de la base du poids de dameuse sur l'efficacité du compactage dynamique pour des sols sablonneux. Des sables de trois densités différentes ont été utilisés pour déterminer l'efficacité du compactage. L'étude porte sur des poids de dameuse de forme conique avec un angle conique correspondant approximativement aux mêmes valeurs que les angles de frottement interne des trois différentes densités de sable. Une dameuse de base plate, de même poids, a également été utilisée en vue d'établir une comparaison. Les résultats indiquent une augmentation significative de l'amélioration du sol lorsque l'on utilise une charge à base conique plutôt que plate.
Transient Response Simulation of an Off-Road Motorcycle with Conventional and Multicell Tire Inflation Mechanisms
Authors: Richards Christopher M. , Summers Thomas Wade 
Published: March 2007

Abstract
Resistance to complete loss of inflation pressure due to puncture is the primary purpose for using nonconventional multicell tire inflation mechanisms. However, recent subjective testing of one particular multicell mechanism also reveals beneficial ride performance characteristics. To gain scientific understanding of this additional benefit, an off-road motorcycle model is developed. Pneumatic stiffness behavior of a conventional inner-tube and the multicell inflation mechanism is described by a simplified tire model which has been shown to accurately predict experimentally measured static stiffness data. Numerically simulated transient response data from the vehicle model is used to evaluate ride performance characteristics when the two mechanisms are used for tire inflation. Data analysis is also performed to reveal why performance improves when the multicell mechanism is utilized. The procedure is validated using experimental data collected on a real vehicle under conditions similar to the numerical simulation.
The Impact of Plus-Sized Wheel/Tire Fitment on Vehicle Stability
Authors: Daws J. W. , Larson R. E. , Brown J. C. 
Published: March 2007

Abstract
Plus-sizing in the tire industry is the growing practice of replacing a vehicle’s original equipment wheel size with a larger diameter wheel and replacing the tire with a lower-aspect-ratio tire of the same diameter. This practice is normally associated with aftermarket sales, and there is a growing trend for vehicle dealerships to fit these larger wheels/tires to new cars. This paper discusses the general practice and its effect on some of the performance characteristics of vehicles. A vehicle taken from the NHTSA New Car Assessment Program’s rollover “Star” rating program is used to illustrate the impact of plus sizing on static stability. Some of the dynamic tire effects that could influence vehicle stability are discussed, and preliminary testing data on the dynamic impact of plus sizing are presented.
Measuring Lateral Tire Performance on Winter Surfaces
Authors: Phetteplace G. , Shoop S. , Slagle T. 
Published: March 2007

Abstract
The Army has approved and funded an Army Technology Objective (ATO) entitled “High Fidelity Ground Platform and Terrain Mechanic Modeling.” This ATO is being jointly performed by the Engineer Research and Development Center (ERDC) along with the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) and the Army Research Laboratory (ARL). Two of the ERDC laboratories are participating in the ATO: The Cold Regions Research and Engineering Laboratory (CRREL) in Hanover, NH, and the Geotechnical and Structures Laboratory in Vicksburg, MS. One of CRREL’s major milestones for the ATO is to extend two-dimensional ground contact models for the TARDEC Real-time Simulator to full three-dimensional functionality by including the lateral forces. Central to that requirement is an understanding of lateral forces on all-seasons terrain. While modeling of vehicle tire lateral force interactions for typical hard paved surfaces is well understood, there is a need to translate that understanding in a consistent manner into off-road terrain and low-friction surfaces. The experimental work described in this paper is fundamental to gaining the required understanding. The experimental work, performed with instrumented vehicles, was accomplished via a contract with the Nevada Automotive Test Center. The testing included both lateral and longitudinal traction tests on winter surfaces. The surfaces included ice, packed snow, and disaggregated snow. The two principal tires tested were an all-season LT235/75R15 that has been the subject of many tests on the CRREL instrumented vehicle, and a tire used on the military’s HMMWV, size 37×12.50R16.5. For each tire and surface, tests at a minimum of two inflation pressures were conducted. For each surface/tire/inflation variant a minimum of ten replicate data sets were obtained. This paper reports the results of the tests and the analysis conducted to date.
Endoscopic Lothrop Procedure: The University of Miami Experience
Authors: Casiano Roy R. , Livingston Jeffrey A. 
Published: March 2007

Over a 2-year period, 21 patients with clinical and radiologic evidence of persistent or recurrent frontal sinusitis who had a prior ethmoidectomy and/or frontal sinusotomy underwent an endoscopic Lothrop procedure. The patients’ chief complaints were headaches (13), nasal obstruction and/or purulent rhinorrhea (4), orbital abscess/cellulitis (2), anosmia (1), and cough (1). Preoperative frontal headaches were present in 19 patients. The common frontal ostium remained patent (>50% of intraoperative size) by flexible fiberoptic examination and transillumination 2–24 months postoperatively in 12 of 21 patients (57%). Eighteen of 21 patients (86%) had improved or resolved chief complaints. All but 4 of 19 patients (21%) with preoperative frontal headaches had improved or resolved symptoms. Two patients required additional surgery during the follow-up period. The endoscopic Lothrop procedure is a viable option before frontal sinus obliteration in patients with recurring frontal sinusitis who have failed conventional endoscopic techniques. The surgical technique and results will be presented.
Clinical and molecular characterization of a patient with a 2q31.2‐32.3 deletion identified by array‐CGH
Authors: Mencarelli Maria Antonietta , Caselli Rossella , Pescucci Chiara , Hayek Giuseppe , Zappella Michele , Renieri Alessandra , Mari Francesca 
Published: March 2007

AbstractWe report on a patient with a de novo interstitial deletion of the long arm of chromosome 2 involving bands 2q31.2‐2q32.3. The patient shows severe mental retardation, absence of speech, sleep disturbances, behavioral problems, and some dysmorphic features. In particular, he presents with macrocephaly, high forehead, thick and coarse hair, thick eyebrows, synophrys, increased inner and outer canthal distance, bifid nasal tip, high palate, micrognathia, dysmorphic right ear, and long and tapering fingers. Array‐CGH analysis allowed us to identify and characterize a 2q interstitial deletion of about 13 Mb, involving the segment between cytogenetic bands 2q31.2 and 2q32.3. The deletion was confirmed by quantitative PCR. We compare the phenotype of our patient with those already reported in literature. In particular, we discuss the similarities shared with two recently reported patients, studied by array‐CGH, who show an overlapping deletion. The common clinical features are: long face, high forehead, abnormal teeth and ears, midface hypoplasia, high palate, micrognathia, transparent and thin skin, high frequency of inguinal hernia, severe development impairment, and behavioral problems. Some genes located in the deleted region may be good candidates for the neurological phenotype such as ZNF533 and MYO1B, which are both involved in neuronal function. Furthermore, the GLS gene could be a good candidate in generating the behavioral phenotype in the patient. In fact, it encodes for the major enzyme yielding glutamate from glutamine and it can be implicated in behavioral disturbances in which glutamate acts as a neurotransmitter. © 2007 Wiley‐Liss, Inc.
SNP fine mapping of chromosome 8q24 in bipolar disorder
Authors: Zandi Peter P. , Avramopoulos Dimitrios , Willour Virginia L. , Huo Yuqing , Miao Kuangyi , MacKinnon Dean F. , McInnis Melvin G. , Potash James B. , DePaulo J. Raymond 
Published: March 2007

AbstractWe previously reported linkage to chromosome 8q24 in bipolar disorder (BP) with a LOD of 3.32. We fine mapped the locus with SNPs and tested for association with BP in families with evidence of linkage to the region. We genotyped 249 informative SNPs over 3.4 Mb in an initial sample of 155 nuclear families (352 affected offsprings), and followed up the best findings by genotyping six of the most significantly associated SNPs in a replication sample of 103 nuclear families (231 affected offsprings). We used FBAT and GIST for association tests. Two clusters of SNPs emerged with the strongest evidence of association. The first consisted of three SNPs, approximately 3 kb 5′ from the gene ST3GAL1. These SNPs were associated with BP in the initial sample by FBAT (best P = 0.001) and GIST (best P = 0.05) and associated in the replication sample by FBAT (best P = 0.04). The second cluster consisted of four SNPs (one of which was not genotyped in the replication sample), approximately 480 kb 5′ of ST3GAL1 in a relative gene desert. These SNPs were associated with BP in the initial sample by FBAT (best P = 0.007) and GIST (best P = 0.03), and marginally associated in the replication sample by FBAT (best P = 0.07) and GIST (P = 0.04). ST3GAL1 belongs to a family of glycosyltransferase proteins, several members of which are highly expressed in the brain and involved in neurogenesis. Several other interesting candidate genes are also located nearby. The congruence of findings across methods and samples suggests further investigation is warranted in these two targeted regions. © 2007 Wiley‐Liss, Inc.