bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recognition of psychiatric disorders, and self‐perceived problems. A follow‐up study from age 8 to age 18
Authors: Sourander Andre , Haavisto Antti , Ronning John A. , Multimäki Petteri , Parkkola Kai , Santalahti Päivi , Nikolakaros Georgios , Helenius Hans , Moilanen Irma , Tamminen Tuula , Piha Jorma , Kumpulainen Kirsti , Almqvist Fredrik 
Published: September 2005

Objective: To study the rate of, and factors associated with, recognition of psychiatric disorders and self‐perceived problems among 18‐year‐old adolescent boys.Method: The study population consisted of 2347 Finnish boys born during 1981 attending military call‐up (79.7% of the original sample). At age 8, the boys were evaluated by parental and teacher Rutter scales and by self‐reports using the Child Depression Inventory (CDI). At military call‐up 10 years later, the boys filled in the Young Adult Self‐Report (YASR). Information about psychiatric disorders recognized at the military call‐up health examination was obtained from the national military register.Results: About 4.6% of boys were recognized as having a psychiatric disorder at the military call‐up medical examination. In addition, 23.1% of boys reported emotional, behavioral or relational difficulties but were not recognized as having an ICD 10 psychiatric diagnosis at the military call‐up medical examination. A higher level of psychopathology, problems across different life domains and early onset of problems were more strongly associated with recognition of psychiatric disorder than with self‐reports of difficulties without a recognized psychiatric disorder. All informant sources, parents, teachers and children themselves at age 8, independently predicted recognition of psychiatric disorders and perceived difficulties 10 years later.Conclusions: Only a minority of adolescents with psychiatric problems are recognized as having a psychiatric disorder in the health services. Efforts to prevent psychiatric disturbance in early life are emphasized. The use of screening methods in school health settings to detect children in need of child mental health services is justified.
Bivariate linkage scan for reading disability and attention‐deficit/hyperactivity disorder localizes pleiotropic loci
Authors: Gayán J. , Willcutt E.G. , Fisher S.E. , Francks C. , Cardon L.R. , Olson R.K. , Pennington B.F. , Smith S.D. , Monaco A.P. , DeFries J.C. 
Published: September 2005

Background:  There is a growing interest in the study of the genetic origins of comorbidity, a direct consequence of the recent findings of genetic loci that are seemingly linked to more than one disorder. There are several potential causes for these shared regions of linkage, but one possibility is that these loci may harbor genes with manifold effects. The established genetic correlation between reading disability (RD) and attention‐deficit/hyperactivity disorder (ADHD) suggests that their comorbidity is due at least in part to genes that have an impact on several phenotypes, a phenomenon known as pleiotropy.Methods:  We employ a bivariate linkage test for selected samples that could help identify these pleiotropic loci. This linkage method was employed to carry out the first bivariate genome‐wide analysis for RD and ADHD, in a selected sample of 182 sibling pairs.Results:  We found evidence for a novel locus at chromosome 14q32 (multipoint LOD = 2.5; singlepoint LOD = 3.9) with a pleiotropic effect on RD and ADHD. Another locus at 13q32, which had been implicated in previous univariate scans of RD and ADHD, seems to have a pleiotropic effect on both disorders. 20q11 is also suggested as a pleiotropic locus. Other loci previously implicated in RD or ADHD did not exhibit bivariate linkage.Conclusions:  Some loci are suggested as having pleiotropic effects on RD and ADHD, while others might have unique effects. These results highlight the utility of this bivariate linkage method to study pleiotropy.
Collaborative analysis of DRD4 and DAT genotypes in population‐defined ADHD subtypes
Authors: Todd Richard D. , Huang Hongyan , Smalley Susan L. , Nelson Stanley F. , Willcutt Erik G. , Pennington Bruce F. , Smith Shelley D. , Faraone Stephen V. , Neuman Rosalind J. 
Published: September 2005

Background:  It has been proposed that some of the variability in reporting of associations between attention deficit hyperactivity disorder (ADHD) and candidate genes may result from mixing of genetically heterogeneous forms of ADHD using DSM‐IV criteria. The goal of the current study is to test whether population‐based ADHD subtypes defined by latent class analysis help resolve issues of variable findings across individual gene association studies.Methods:  Three studies which had previously reported no associations between polymorphisms of the DRD4 and DAT genes and DSM‐IV defined ADHD were reanalyzed using population‐based and DSM‐IV defined ADHD subtypes.Results:  Across studies no significant associations were found for either DRD4 or DAT polymorphisms using DSM‐IV ADHD subtypes. In contrast, a significant association was found between the combined data set for the 440 base pair 3′ DAT VNTR polymorphism and population‐defined severe combined ADHD (OR = 1.25, p = .01). A marginally significant association was also found between the 7 repeat DRD4 allele and population‐defined severe combined ADHD.Conclusion:  Use of alternative population‐based defined ADHD subtypes may help resolve some of the variable results presented for candidate gene association studies in ADHD.
High sibling correlation on methylphenidate response but no association with DAT1‐10R homozygosity in Dutch sibpairs with ADHD
Authors: van der Meulen Emma M. , Bakker Steven C. , Pauls David L. , Oteman Nicole , Kruitwagen Cas L.J.J. , Pearson Peter L. , Sinke Richard J. , Buitelaar Jan K. 
Published: September 2005

Background:  A minority of patients with attention‐deficit hyperactivity disorder (ADHD) do not respond favorably to methylphenidate. This has been partially associated with homozygosity for the Dopamine transporter (DAT1) 10‐repeat allele and the presence of one or two Dopamine D4 receptor (DRD4) 7‐repeat alleles. This study examined the sibling correlation of methylphenidate response rate and the possible association between response rate and these risk alleles.Methods:  A sample of 82 Dutch children with ADHD, from 54 families, (including 30 singletons and 28 sib pairs), who used methylphenidate, was phenotyped according to DSM‐IV criteria. Patients were members of affected sib pairs and were genotyped for DAT1 and DRD4. The sibling Intraclass Correlation Coefficient for methylphenidate response rate was calculated. The association between individual response rates and the risk alleles was examined using linear regression techniques.Results:  The Intraclass Correlation Coefficient was significant (r = .563, p = .001). No evidence was found establishing an association between methylphenidate response and DAT1‐homozygosity. There was a positive trend towards association with the presence of one or two DRD4‐7R alleles.Conclusions:  The sibling correlation may indicate a familial clustering of methylphenidate response. This response is possibly associated with the presence of one or two alleles at the DRD4‐7R locus, but not with DAT1‐10R homozygosity in the Dutch population.
Introductory guide to the language of molecular genetics
Authors: Eley Thalia C. , Craig Ian W. 
Published: September 2005

Background: This special section on molecular genetics was invited in order to raise awareness of the potential of molecular genetic approaches to inform child psychologists, psychiatrists and related professionals. As much of the terminology is specific to the field, this introductory guide aims to aid readers who may be unfamiliar with the approaches of this discipline.Methods: Basic terminology and genetic processes are described, with sections covering ‘The Human Genome’ and ‘Genetic Markers’.Results: The range of genetic markers is growing all the time, but those that are thought to be functional and/or are highly variable are particularly useful.Conclusions: Genotyping approaches that offer high efficiency, thus allowing for large numbers of genotypes on large numbers of individuals, are likely to come to the fore in the next few years.
Introductory guide to the statistics of molecular genetics
Authors: Eley Thalia C. , Rijsdijk Frühling 
Published: September 2005

Background:  This introductory guide presents the main two analytical approaches used by molecular geneticists: linkage and association.Methods:  Traditional linkage and association methods are described, along with more recent advances in methodologies such as those using a variance components approach.Results:  New methods are being developed all the time but the core principles of linkage and association remain the same. The basis of linkage is the transmission of a marker along with a disease within families, whereas association is based on the comparison of marker frequencies in case and control groups.Conclusions:  It is becoming increasingly clear that effect sizes of individual markers on diseases and traits are likely to be very small. As such, much greater power is needed, and correspondingly greater sample sizes. Although non‐replication is still a problem, molecular genetic studies in some areas such as attention deficit/hyperactivity disorder (ADHD) are starting to show greater convergence. Epidemiologists and other researchers with large well‐characterized samples will be well placed to use these methods. Inter‐disciplinary studies can then ask far more interesting questions such as those relating to developmental, multivariate and gene–environment interaction hypotheses.
In vitro fertilisation in Sweden: obstetric characteristics, maternal morbidity and mortality
Authors: Källén Bengt , Finnström Orvar , Nygren K.G. , Otterblad Olausson Petra , Wennerholm Ulla‐Britt 
Published: September 2005

Objective  To investigate obstetric characteristics, maternal morbidity and mortality among Swedish women giving birth after in vitro fertilisation (IVF) treatment.Design  Register study.Setting  Nationwide study in Sweden.Sample  All women known to have had IVF in Sweden 1982–2001.Methods  Using Swedish health registers, women who had given birth after IVF were identified from all Swedish IVF clinics and compared with all women who gave birth. Analysis was performed with the Mantel–Haenszel technique.Main outcome measures  Diagnoses during pregnancy, at delivery and at re‐admission within 60 days after delivery and risk of cancer.Results  IVF women had an increased risk of bleeding in early pregnancy [odds ratio (OR) = 4.59, 95% confidence interval (95% CI) 4.08–5.15] and of ovarian torsion during pregnancy (OR = 10.6, 5.69–10.7). They were also more likely to encounter pre‐eclampsia (OR = 1.63, 1.53–1.74), placental abruption (2.17, 1.74–2.72), placenta praevia (3.65, 3.15–4.23), bleeding in association with vaginal delivery (1.40, 1.38–1.50) and premature rupture of membranes (PROM) (2.54, 2.34–2.76). Interventions including caesarean sections (1.38, 1.32–1.43) and induction of labour (1.37, 1.29–1.46) in singleton pregnancies was more frequent. The type of IVF method had little effect on these results, but there was a tendency for women who had received intra‐cytoplasmatic sperm injection (ICSI) to have slightly fewer complications than women having standard IVF. There was a significant decrease in cancer risk after IVF (0.79, 0.69–0.91) but a suggested increase in the risk of ovarian cancer both before (2.70, 1.49–4.91) and after (2.08, 1.15–3.76) IVF. No change in mortality was observed.Conclusions  Women treated with IVF had an increased obstetric morbidity. This seems to contribute little to the well‐known increased risk of preterm delivery.
The outcomes of pregnancy among imprisoned women: a systematic review
Authors: Knight Marian , Plugge Emma 
Published: September 2005

Objective  To investigate the association between maternal imprisonment during pregnancy and perinatal outcomes.Design  Systematic review and meta‐analysis.Setting  Prisons in developed countries.Population  Imprisoned pregnant women.Methods  Two reviewers extracted the data independently according to a fixed protocol. Studies were included if they were cohort or case–control studies with women identified as being imprisoned at any point during pregnancy and if they included a comparison group of women who had not been imprisoned. Case series without a comparison group of women who were not imprisoned were excluded, as were studies that did not include information on the pre‐specified outcomes.Main outcome measures  Perinatal or infant death, stillbirth, preterm delivery, low birthweight, fetal anomalies and use of breast milk substitutes.Results  Of 28 relevant papers, 10 met the inclusion criteria, involving 1960 imprisoned pregnant women and 10,858 controls. There were significant differences in results between studies comparing imprisoned women with population controls and those making comparisons with disadvantaged control women. Imprisoned women are more likely to deliver prematurely and have a low birthweight baby than population control women. However, when compared with a similarly disadvantaged group, imprisoned woman are less likely to have a stillbirth or low birthweight baby, suggesting imprisonment may have a beneficial effect.Conclusions  Particular perinatal outcomes appear to be improved in imprisoned women compared with similarly disadvantaged women. Imprisonment of the mother has a beneficial effect on the birthweight of her baby.
First trimester threatened miscarriage treatment with human chorionic gonadotrophins: a randomised controlled trial
Authors: Qureshi N.S. , Edi‐Osagie E.C. , Ogbo V. , Ray S. , Hopkins R.E. 
Published: September 2005

Objective  To determine whether administration of exogenous human chorionic gonadotrophin (hCG) treatment improve the pregnancy outcome in first trimester threatened miscarriages.Design  A prospective, double blind, randomised, placebo‐controlled trial.Setting  The Early Pregnancy Assessment Unit, Royal Bolton Hospital, Bolton, United Kingdom.Population  One hundred and eighty‐three women with vaginal bleeding and a viable fetus seen on ultrasound scan (USS) in the first 12 weeks of pregnancy.Methods  The patients were randomised to receive either hCG or placebo treatment until 14 weeks of gestation.Main outcome measures  The primary objective of the trial was to determine the miscarriage rate in the hCG arm compared from the placebo arm.Results  Of the 183 cases, 87 were randomised to treatment with hCG while 96 were randomised to receive a placebo. Forty‐seven (25%) did not comply with the study protocol. The mean [SD] gestational age at presentation was 7 [1.33] weeks. The mean [SD] age of women in study was 27 [5] years in the placebo and 28 [5] in the hCG group. The mean body mass index (kg/m2) was 25 [5] in the study. The number of patients actively bleeding per vaginum at presentation was 85 (93%) in placebo group and 79 (96%) in the hCG group. The median number of hCG or placebo injections for both groups was 7. Ten women (11%) in the placebo group proceeded to have a complete miscarriage, as did 10 women (12%) in the hCG group, relative risk (RR) [95% confidence interval (CI)] of 1.1 (0.63–1.6).Conclusion  Our study showed no evidence of a difference in the outcome of threatened miscarriages when treated with hCG in the first trimester, this may be because our study sample size was small and follow up was suboptimal. A large, randomised, multicentre trial is still needed to establish the usefulness of hCG treatment in cases of threatened miscarriage.
Mode of delivery and severe stress incontinence. A cross‐sectional study among 2625 perimenopausal women
Authors: Fritel Xavier , Ringa Virginie , Varnoux Noëlle , Fauconnier Arnaud , Piault Stéphanie , Bréart Gérard 
Published: September 2005

Objective  To estimate the prevalence of severe stress urinary incontinence (SUI) among perimenopausal women and to examine potential obstetric risk factors.Design  Mail survey of female volunteers for epidemiological research.Setting  Postal questionnaire on SUI.Population  Three thousand one hundred and fourteen women aged 49–61 years who comprised the GAZEL cohort.Methods  Logistic regression using data from the entire cohort to estimate the impact of risk factors. A second logistic regression using data from women who had given birth included obstetric history.Main outcome measure  Prevalence of severe SUI defined by the response ‘often’ or ‘all the time’ to the question ‘Does urine leak when you are physically active, cough or sneeze?’Results  Two thousand six hundred and twenty‐five women (85%) completed and returned the questionnaire The frequency of SUI reported in the preceding four weeks was as follows: ‘never’ 32%, ‘occasionally’ 28%, ‘sometimes’ 26%, ‘often’ 10% and ‘all the time’ 5%. Prevalence of severe SUI was lowest among nulliparous women (7%), but it was similar among parous women regardless of birth number (14–17%). The prevalence of severe SUI was not associated with mode of delivery (14% for women delivered by caesarean only vs 16% for vaginal births). Significant risk factors for severe SUI were high body mass index (BMI >30), diabetes mellitus, previous incontinence surgery, parity and first delivery under the age of 22 years.Conclusion  Previous pregnancy itself is a risk factor for severe SUI among women who reach the age of 50. In this age group the impact of the mode of delivery (spontaneous, forceps or caesarean) on severe SUI is slight.
Recurrence risk in hyperemesis gravidarum
Authors: Trogstad Lill I.S. , Stoltenberg Camilla , Magnus Per , Skjærven Rolv , Irgens Lorentz M. 
Published: September 2005

Objectives  To compare the risk of hyperemesis gravidarum in second pregnancies in women with and without hyperemesis in their first pregnancy, and to determine if this risk changes with changes in paternity or with the interval between deliveries.Design  Cohort study.Setting  Data from the population‐based Medical Birth Registry of Norway, 1967–1998.Sample  All women in the registry with records of their first and second singleton delivery, a total of 547,238 women.Methods  The relative risk of hyperemesis in the second delivery was estimated as odds ratios (ORs) in logistic regression models, controlling for potential confounding factors.Main outcome measures  The main outcome measure was the risk of hyperemesis in the second pregnancy according to hyperemesis in the first pregnancy, interval between deliveries and change in paternity.Results  The risk of hyperemesis was 15.2% in the second pregnancy in women with and 0.7% in women without previous hyperemesis [OR = 26.4, 95% confidence interval (CI) 24.2, 28.7]. The OR did not change after adjustment for maternal age, change in paternity, period of the first delivery and time interval between deliveries. After a change in paternity, the risk of recurrent hyperemesis was 10.9% compared with 16.0% in women without a change in paternity [adjusted OR (aOR) = 0.60, 95% CI 0.39, 0.92]. The risk of hyperemesis in the second pregnancy increased with increasing time interval between deliveries, but only in women with no previous hyperemesis.Conclusions  The primary finding was the high risk of recurrence observed in women with hyperemesis in the first pregnancy. The risk was reduced by a change in paternity. For women with no previous hyperemesis, a long interval between births slightly increased the risk of hyperemesis in the second pregnancy. Further studies are needed to explore the relative impact of genetic and environmental factors and their possible interactions in hyperemesis gravidarum.
Physical activity in the post‐pubertal period is associated with maintenance of pre‐pubertal high bone density – a 5‐year follow‐up
Authors: Valdimarsson Ö. , Sigurdsson G. , Steingrímsdóttir L. , Karlsson M. K. 
Published: September 2005

Objective: To evaluate the association between physical activity (PA) and skeletal growth in girls during adolescence.Design: A 5‐year, observational, population‐based study (Reykjavik, Iceland).Subjects: Seventy‐eight Caucasian girls, mean age 13.4±1.0 (mean±SD) years at baseline.Methods: Bone mineral density (BMD, g/cm2) and bone width (cm) were measured in the forearm by single‐photon absorptiometry at baseline and with dual‐energy X‐ray absorptiometry after 3 and 5 years, when lumbar spine, femoral neck (FN) and total body were also evaluated. Half of the physically active girls were compared with the other half of less active girls.Results: BMD in physically active girls was higher in the forearm at both baseline (P=0.001) and after 5 years (P=0.04) in comparison with less active girls. BMD was higher for the total body (P=0.0001), spine L2–L4 (P=0.02) and FN (P=0.002) in the active girls at age 18. The accrual of forearm BMD and bone width from age 13 to 18 was no different when comparing the two groups.Conclusions: Pre‐pubertal PA is associated with high BMD at age 13 and continued PA is associated with maintenance of high BMD until age 18.
Abnormal Tribological Behavior of Multiwalled Nanotube Rafts Part I: Aligned Rafts
Authors: Yang Wei , Wang Hongtao , Huang Y. 
Published: September 2005

Abstract
When two material surfaces are brought into contact, the classical Amonton’s law predicts a monotonically increasing relation between the frictional force and the normal pressure. An abnormal friction law refers to the case where the friction force declines as the normal pressure increases. We investigate the possibility of abnormal tribological behavior for two surfaces coated with aligned multiwalled nanotube rafts. Part I of the investigation is devoted to the case when two contacting nanotube rafts are aligned to each other, while part II is aimed at more general case of arbitrarily oriented nanotube rafts. The analysis in part I is based on the JKR theory of adhesion and linear elasticity for aligned multiwalled carbon nanotube raft configuration. It gives rise of several interesting predictions. First, two surfaces covered by aligned nanotubes can adhere when bringing into a pressureless contact. Second, the aligned multiwalled nanotube rafts exhibit a detachment work that declines with the contacting pressure. Third, in contrast to the Amonton’s law, the frictional force would decline as the normal pressure increases.
A Self-Consistent Model for the Inelastic Deformation of
Nanocrystalline Materials
Authors: Capolungo L. , Cherkaoui M. , Qu J. 
Published: September 2005

Abstract
A self-consistent scheme is used to describe the behavior of nanocrystalline F.C.C. materials. The material is approximated as a composite with two phases. The inclusion phase represents the grain cores while the matrix phase represents both grain boundaries and triple junctions. The dislocation glide mechanism is incorporated in the constitutive law of the inclusion phase while a thermally activated mechanism accounting for the penetration of dislocations in the grain boundaries is incorporated in the constitutive law of the matrix phase. The model is applied to pure Cu and the results are compared with various experimental data.