Universal approach for local higher-order wavefront tracing equations for complex optical systems.

Analytical wave tracing, including higher-order aberrations, is the state of the art, but at present it is only provided for single propagation or refraction. A complex optical system being a sequence of many refractive surfaces and gaps in between can only be treated by successive application of elementary wave-tracing steps, which is time-consuming for a large number of surfaces or even impossible if a system specification by surfaces is not available. Provided the ray transfer properties of a system are summarized as a nonlinear function f whose Jacobian is the ABCD matrix of the system, by multiple derivative we obtain wave-tracing equations for the wavefront's local derivatives of any desired order. The outgoing wavefront derivative of any order can be written as a sum of multinomials of derivatives of the incoming wavefront, weighted by system-dependent coefficients and by powers of the factor ß=(A-BE2)-1, where E2 is the second-order aberration of the incoming wavefront. Compared to stepwise wave tracing, this approach is extremely efficient when tracing many different wavefronts through one fixed optical system.

Monoamine oxidase A polymorphism moderates stability of attention problems and susceptibility to life stress during adolescence.

Attention problems affect a substantial number of children and adolescents and are predictive of academic underachievement and lower global adaptive functioning. Considerable variability has been observed with regard to the individual development of attention problems over time. In particular, the period of adolescence is characterized by substantial maturation of executive functioning including attentional processing, with the influence of genetic and environmental factors on individual trajectories not yet well understood. In the present investigation, we evaluated whether the monoamine oxidase A functional promoter polymorphism, MAOA-LPR, plays a role in determining continuity of parent-rated attention problems during adolescence. At the same time, a potential effect of severe life events (SLEs) was taken into account. A multi-group path analysis was used in a sample of 234 adolescents (149 males, 85 females) who took part in an epidemiological cohort study at the ages of 11 and 15 years. Attention problems during early adolescence were found to be a strong predictor of attention problems in middle adolescence. However, in carriers of the MAOA-LPR low-activity variant (MAOA-L), stability was found to be significantly higher than in carriers of the high-activity variant (MAOA-H). Additionally, only in MAOA-L carriers did SLEs during adolescence significantly impact on attention problems at the age of 15 years, implying a possible gene × environment interaction. To conclude, we found evidence that attention problems during adolescence in carriers of the MAOA-L allele are particularly stable and malleable to life stressors. The present results underline the usefulness of applying a more dynamic GxE perspective.

First fusion proton measurements in TEXTOR plasmas using activation technique.

MeV particle loss measurements from fusion plasmas, in particular alpha particles, remain difficult in large fusion devices and further R&D is needed for ITER. This paper describes the first attempt to measure 3 MeV escaping fusion protons emitted from TEXTOR tokamak plasmas using activation technique. This technique was successfully demonstrated, initially, in 2006 on the JET tokamak. An ion camera equipped with a collimator and several types of activation detectors was installed inside the TEXTOR vacuum vessel to perform these measurements. After irradiation, the detectors were analyzed using ultra low level gamma-ray spectrometry at the HADES underground laboratory. 3 MeV escaping fusion protons were detected in larger number -~6 times more--compared to earlier measurements using this technique on JET. Another major progress was the reduction of the cooling time by a factor of 50, which made possible to detect radionuclides with half-life of less than 90 min.

Increasing association between a neuropeptide Y promoter polymorphism and body mass index during the course of development.

OBJECTIVE: To investigate the association of the neuropeptide Y (NPY) promoter polymorphism rs16147 with body mass index (BMI) during the course of development from infancy to adulthood. DESIGN: Longitudinal, prospective study of a German community sample. SUBJECTS: n = 306 young adults (139 males, 167 females). MEASUREMENTS: Participants' body weight and height were assessed at the ages of 3 months and 2, 4.5, 8, 11, 15 and 19 years. NPY rs16147 was genotyped. RESULTS: Controlling for a number of possible confounders, homozygote carriers of the rs16147 C allele exhibited significantly lower BMI scores when compared with individuals carrying the T allele. In addition, a significant genotype by age interaction emerged, indicating that the genotype effect increased during the course of development. CONCLUSIONS: This is the first longitudinal study to report an association between rs16147 and BMI during childhood and adolescence. The finding that this effect increased during the course of development may either be due to age-dependent alterations in gene expression or to maturation processes within the weight regulation circuits of the central nervous system.

Derivation of the refraction equations for higher-order aberrations of local wavefronts at oblique incidence.

From the literature the calculation of power and astigmatism of a local wavefront after refraction at a given surface is known from the vergence and Coddington equations. For higher-order aberrations (HOAs) equivalent analytical equations do not exist. Since HOAs play an increasingly important role in many fields of optics, e.g., ophthalmic optics, it is the purpose of this study to extend the "generalized Coddington equation" to the case of HOA (e.g., coma and spherical aberration). This is done by local power series expansions. In summary, with the results presented here, it is now possible to calculate analytically the local HOA of an outgoing wavefront directly from the aberrations of the incoming wavefront and the refractive surface.

Early predictors of antisocial developmental pathways among boys and girls.

OBJECTIVE: We investigated in a high-risk sample the differential impact of biological and psychosocial risk factors on antisocial behaviour pathways. METHOD: One hundred and thirty-eight boys and 155 girls born at differing degrees of obstetric and psychosocial risk were examined from birth until adolescence. Childhood temperament was assessed by a highly-structured parent-interview and standardized behavioural observations, adolescent temperament was measured by self-report. Neurodevelopmental variables were assessed by age-specific developmental tests. Emotional and behaviour problems were measured at the ages of 8 and 15 by the Achenbach scales. RESULTS: In both genders, psychosocial adversity and early self-control temperament were strongly associated with early-onset persistent (EOP) antisocial behaviour. Psychosocial adversity and more severe externalizing problems differentiated the EOP from childhood-limited (CL) pathway. In girls, adolescent-onset (AO) antisocial behaviour was strongly associated with novelty seeking at 15 years. CONCLUSION: Our findings emphasize the need for early support and intervention in psychosocially disadvantaged families.

Association between ADHD and smoking in adolescence: shared genetic, environmental and psychopathological factors.

The present study aimed to examine the extent to which the co-occurrence of ADHD and smoking in adolescents could be attributed to common genetic, environmental and psychopathological factors. Data are from an ongoing prospective study of the outcome of early risk factors. At age 15 years, 305 adolescents completed self-report questionnaires measuring tobacco consumption and deviant peer affiliations. Lifetime psychiatric diagnoses were obtained using standardized interviews. DNA was genotyped for the dopamine D4 receptor (DRD4) gene exon III polymorphism. Adolescents with a lifetime diagnosis of ADHD displayed significantly higher smoking activity than non-ADHD controls. A major component of this association could be accounted for by deviant peer affiliations and the comorbidity with oppositional-defiant and conduct disorder, while a minor part was attributable to DRD4 in males but not in females. These findings suggest that the association of ADHD with smoking relies on risk factors shared by the two behaviors.

[Depressive disorders and conduct disorders in childhood and adolescence. Prevalence, course, and risk factors]. / Depressive Störungen und aggressiv-dissoziale Störungen im Kindes- und Jugendalter. Prävalenz, Verlauf und Risikofaktoren.

Mental disorders belong to the most frequent disorders in the community and lead to noticeable functional impairments. The lifetime prevalence of clinical depression (ICD-10 diagnoses F33, F34) up to age 25 is 12.7%, showing a female-male ratio of 2:1. From adolescence onwards, persistence rates of depressive disorders are comparably as high as those found in externalizing disorders. Subclinical depression (ICD-10 subthreshold disorders) at ages 8 and 13 increases the risk for later clinically relevant mental disorders. Conduct disorders (ICD-10 diagnoses F91, F92) are the most frequent mental disorders in children and adolescents with lifetime prevalence rates of 22.4% up to age 25. Conduct disorders show unfavorable courses beginning at preschool age. Precursors of later disorders can be detected as early as toddlerhood. Adverse family factors in childhood and early externalizing problems of the child were most predictive for later conduct disorders. Therefore, the need for early prevention of conduct disorders is highlighted. The focus should be on families with low socioeconomic status (objective: strengthening family and child resources). For depressive disorders, we recommend testing and evaluating the indicated prevention programs in adolescence (objective: strengthening the resources of the adolescent).

[Analysis of EEG coherence in examination of an automation deficit in reading-spelling disorder--a pilot study]. / EEG-Kohärenzanalyse zur Untersuchung eines Automatisierungsdefizits bei Lese-Rechtschreibstörung--eine Pilotstudie.

OBJECTIVES: Do dyslexic children exhibit a general automatizational deficit as well as a phonological deficit? METHODS: In 16 children aged 9-11 years the reaction time, the number of mistakes and EEG (19 scalp electrodes) were measured in three experiments (verbal and nonverbal). The EEG data was baseline-corrected and after a fast fourier transformation, analyzed with the coherence tool of the Brainvision Software. RESULTS: The dyslexic group made more mistakes than the control group on all tasks but their reaction times were significantly longer only on the verbal tasks. There were no coherence differences on the nonverbal task. On the language-dependent tasks the dyslexics showed higher total-frontal and lower left-frontal coherences only in the theta-frequency range, while in the alpha and beta frequency ranges coherences did not differ. CONCLUSIONS: A language-dependent cognitive automatizational deficit in the dyslexic group is assumed that is depicted by the higher synchronization of total-frontal coherences (involvement of the central executive) and is based on the less established functional coupling of cortical subsystems for language processing.

The management of chronic tinnitus: comparison of an outpatient cognitive-behavioral group training to minimal-contact interventions.

OBJECTIVE: Using a randomized group design, the efficacy of an outpatient cognitive-behavioral Tinnitus Coping Training (TCT) was compared to two minimal-contact (MC) interventions. METHODS: TCT was conducted in a group format with 11 sessions (total n=43). One MC [MC-E (education), n=16] consisted of two group sessions in which education on tinnitus was presented and self-help strategies were introduced. The second MC [MC-R (relaxation), n=16] comprised four sessions. Besides education, music-supported relaxation was suggested as self-help strategy and audiotapes with relaxing music were provided. Furthermore, a waiting-list control group was installed (WC, n=20). Data were assessed at baseline (pretherapy) and at posttherapy period. Only TCT was additionally evaluated at a 6-month and a 12-month follow-up. Several outcome variables (e.g., awareness of tinnitus) were recorded in a tinnitus diary. Tinnitus coping and disability due to tinnitus were assessed by questionnaires. Subjective ratings of improvement were also requested from the patients. Furthermore, inventories of psychopathology were given to the patients. RESULTS: Findings reveal highly significant improvements in TCT in comparison to the control group (WC). MC interventions do not differ significantly from each other, but are superior to WC in a few domains of outcome. Outcome in TCT is somewhat superior to combined MC interventions in two domains of data, but not regarding disability reduction. Effect sizes, nevertheless, indicate distinct differences in degree of improvement, with TCT achieving the best results. CONCLUSIONS: A sequential scheme for the treatment of chronic tinnitus is discussed on the basis of cost-effectiveness considerations.

[Motor, cognitive and socio-emotional development of 11-year-olds with early childhood risk factors: late sequelae]. / Motorische, kognitive und sozial-emotionale Entwicklung von 11-Jährigen mit frühkindlichen Risikobelastungen: späte Folgen.

OBJECTIVES: The investigation of the impact of early childhood risk factors on developmental outcome at the age of 11 years. METHODS: The onset and course of developmental and behavioral disturbances were examined in a prospective longitudinal study of a sample of 362 children born with different risks. Organic (obstetric complications) and psychosocial risks (family adversity) were varied in a two-factorial design. Measures of motor, cognitive and social-emotional outcome were obtained from 341 children aged 11 years (168 boys, 173 girls, corresponding to 94.2% of the initial sample). Previous assessments had been conducted at the ages of 3 months, and again at the ages of 2, 4 1/2 and 8 years. RESULTS: The negative impact of early risk factors persisted into late childhood. Rates of developmental and behavioral disturbances in high-risk children were up to three times higher than in non-risk children. Both organic and psychosocial risks contributed to adverse outcomes. While organic complications were related to disturbances in motor and cognitive development, the detrimental effects of psychosocial adversity pertained to social-emotional functioning. Late sequelae of pre- and perinatal complications were found especially in cognitive outcome and school performance. The cumulative effect of early risks was best explained by summing up the single risk effects. CONCLUSIONS: Early risk factors have specific and long-term sequelae resulting in adverse school outcomes at later ages.

Differential development of infants at risk for psychopathology: the moderating role of early maternal responsivity.

The development of behaviour problems in infants born with biological risk (low birthweight) and psychosocial risk (psychosocially disadvantaged family) was studied in a sample of 347 children (171 males, 176 females) at the ages of 2, 4:6, and 8 years. In the search for factors that moderate the effects of early risks, the role of early responsive caregiving was examined. Results indicate that infants at psychosocial risk exhibited both more externalizing and internalizing problems across ages than infants not at psychosocial risk, while no overall differences were apparent between normal- and low-birthweight groups. With one exception, no interactions between biological and psychosocial risk factors emerged, suggesting that their simultaneous effect is largely additive. Maternal responsivity was found to moderate the effects of low birthweight on hyperkinetic and internalizing problems as well as to influence the consequences of family disadvantage on total problems. These findings stress the importance of early parenting in the behavioural development of at-risk children.

Child development after maternal tocolysis with beta-sympathomimetic drugs.

The psycho-social development of both preterm and term children whose mothers reported tocolytic treatment was assessed at the ages of 2, 4.5, and 8 years. Term children exposed to tocolysis showed a higher rate of psychiatric disorders as well as poorer cognitive and motor performance than controls. In the preterm children no adverse impact of tocolysis could be found. The results are discussed concerning possible ways in which tocolytic treatment may influence child development. Restrictions because of the preliminary character of this study and the need of further prospective studies to clarify the developmental impact of tocolysis are also considered.

[Mother-child interaction and externalizing disorders in elementary schoolchildren]. / Mutter-Kind-Interaktion und externalisierende Störungen bei Kindern im Grundschulalter.

OBJECTIVES: The behavior of eight-year-old children with externalizing disorders (ADHD and CD) in interaction with their mothers was examined. METHODS/RESULTS: Mothers of ADHD children were more restrictive and negative towards their children and showed less adequate control than did mothers of normal children. ADHD children paid less attention, were less assertive and helpless, and were more impulsive than controls. CD children were more negative towards their mothers, and were more aggressive and provocative than normal children, while their mothers were more impatient. CONCLUSIONS: An interaction between aggressive child behavior and maternal restrictiveness contributed to increased conduct problems. Hyperactivity was enhanced by the interaction between the impulsive behavior of the child and the aversive maternal response.

Epidemiology and prognosis of specific disorders of language and scholastic skills.

Data from a prospective longitudinal study on the development of children born at biological and psychosocial risk were utilised to examine language and learning abilities of 320 children at ages 4.5 and 8 years. Following the research criteria of the ICD-10, specific developmental disorders of speech and language and specific developmental disorders of scholastic skills were diagnosed. Data were also provided for a clinical and general low achievement group according to less stringent criteria. Frequencies in the risk population were low for specific disorders (ICD-10) (0.6%-3.7% depending on age and type of disorder). Higher frequencies were found when a clinical definition (0.6%-13.6%) or overall low achievement score (0.6%-18.6%) was chosen. The impact of well-documented organic and psychosocial risks was analysed. Organic risk affected language abilities at 4.5 years of age but neither language nor learning abilities at 8 years of age. Psychosocial aspects of a child's environment proved to be associated with both specific language and learning abilities. Stability of language disorders, association between language and reading/spelling disorders as well as gender effects were investigated.

Behavioral sequelae of perinatal insults and early family adversity at 8 years of age.

OBJECTIVE: This prospective longitudinal study investigated the simultaneous impact of early biological and psychosocial risk factors on behavioral outcome at school age. METHOD: A cohort of 362 children born between 1986 and 1988 with different biological (perinatal insults) and psychosocial risk factors (family adversity) was followed from birth to school age. When their children were aged 8 years, parents of 89.0% of the initial sample completed the Child Behavior Checklist (CBCL). RESULTS: More externalizing as well as internalizing problems were found in children born into adverse family backgrounds, whereas no differences at broad-band syndrome level were apparent between groups with varying obstetric complications. Children with family risk factors had higher scores on 5 of the 8 CBCL scales (including attention, delinquent, and aggressive problems), whereas children with perinatal risk factors had more social and attention problems than children in the nonrisk groups. With one exception, no interactions between risk factors emerged, indicating that perinatal and family risk factors contributed independently to outcome. The differences between risk groups applied irrespective of gender. CONCLUSIONS: The adverse impact of family adversity clearly outweighed the influence of obstetric complications in determining behavioral adjustment at school age.

Mutagenic properties of 1,2,3,4-tetrahydronaphthaline-1-hydroperoxide, a model compound for organic peroxides in Diesel exhaust.

The genotoxicity of the organic peroxide 1,2,3,4-tetrahydronaphthaline-1-hydroperoxide (or tetraline-1-hydroperoxide, THP) was investigated in the Ames assay without a metabolic activating system using Salmonella typhimurium strains TA 98, TA 100, and TA 102. THP served as a model compound for higher organic peroxides, which can arise from autoxidation of hydrocarbons, e.g. in Diesel exhaust. While THP induced no mutagenic response in S. typhimurium TA 98, it was directly mutagenic in strains TA 100 and TA 102. These data, along with findings on mutagenic properties of other alkyl hydroperoxides, suggest that such compounds deserve further investigation regarding their genotoxic potential and occurrence in the environment.

[Risks and protective factors in early childhood development: empirical findings]. / Risiko- und Schutzfaktoren der frühkindlichen Entwicklung: Empirische Befunde.

A common result of many studies of children at risk for developmental disorder is the heterogeneity of individual reactions to adversity. One attempt to explain the differential outcome of children at risk lies in the assumption of protective factors. In a prospective study of 362 infants the significance of pre- and perinatal complications (early biological risks) and of adverse family living circumstances (early psychosocial risks) on child development at 4 1/2 years was examined. Additionally, to study the interplay between risk and protective factors a number of mother-child and family characteristics potentially favourable to early development were assessed. Results indicated that early risk factors made a significant contribution to child development at preschool age. Using multiple risk indices, between 10 and 20% of the variance of the developmental outcome at 4 1/2 years was explained. Significant predictors of later developmental disorders were neonatal seizures and very low birth weight among the biological risks and low educational level of the parents, early parenthood and unwanted pregnancy among the psychosocial risks. The contribution of early protective factors to developmental outcome, however, was only limited. The high overlap with risk factors, the low specific predictive power and the lack of a moderator effect question the theoretical usefulness of a global concept of protective factors. However, when interactions between specific risk and protective factors were studied, there was evidence of a buffer effect of a successful early mother child interaction.

At risk for language disorders? Correlates and course of language disorders in preschool children born at risk.

The language abilities of 324 children of an at-risk population were investigated at age 2 and 4.5 y. Modified research criteria of the ICD-10 for specific developmental disorders of speech and language were applied. Frequencies between 4% and 7%, depending on age and type of disorder, were diagnosed among children whose performance on the language measure was only 1 instead of ICD-10's 2 SD below group mean, but the discrepancy measure of 1 SD between non-verbal language score and language measure was retained. Psychosocial aspects of a child's environment proved to be better predictors of later language disorders than obstetric complications. Stability of specific language disorders was on the whole fairly low, but children who perform below age level on language measures remained at risk. Gender differences are almost compensated by the age 4.5 y.

Developmental outcome of infants born with biological and psychosocial risks.

The significance of prenatal and perinatal complications (biological risk) and of family adversity (psychosocial risk) on early child development was examined in a prospective study. Developmental outcome of 350 infants was assessed by measures of motor, cognitive, and social-emotional functioning at 3, 24, and 54 months. Results indicated a differential impact of risk factors on specific outcomes. Whereas psychosocial risks became more prominent with growing age and were related to poorer child outcome in all areas of functioning, biological risks decreased in influence and predominantly resulted in poorer motor development. The contributions of biological and psychosocial risks on outcomes were additive. A number of individual risk factors emerged as significant predictors of later maladaptation.