The active zone is a specialized region of the presynaptic plasma membrane where synaptic vesicles dock and fuse. In this study, we have investigated the cellular mechanism underlying the transport and recruitment of the active zone protein Piccolo into nascent synapses. Our results show that Piccolo is transported to nascent synapses on an approximately 80 nm dense core granulated vesicle together with other constituents of the active zone, including Bassoon, Syntaxin, SNAP-25, and N-cadherin, as well as chromogranin B. Components of synaptic vesicles, such as VAMP 2/synaptobrevin II, synaptophysin, synaptotagmin, or proteins of the perisynaptic plasma membrane such as GABA transporter 1 (GAT1), were not present. These studies demonstrate that the presynaptic active zone is formed in part by the fusion of an active zone precursor vesicle with the presynaptic plasma membrane.

As bleeding in the neck region is a potentially life-threatening complication, we found it imperative to concretize the frequency and to identify possible reasons for this complication. A national database of all thyroid surgery performed inside the specialty of ENT Head and Neck Surgery (THYKIR) was established in January 2001. This nationwide cohort study represents 5,490 patients included until December 2007. Overall hemorrhage frequency was 4.2% with a wide variation among departments. Multiple regression analysis identified age, male gender, malignant histology and extent of surgery as independent risk factors for hemorrhage. Increased hospital stay and infection rates were found in patients treated with drainage. The median time for onset of postoperative hemorrhage was 3 h (range 0-105). Compared with international literature our incidence of post-thyroidectomy hemorrhage is relatively high. Improvement might be reached by the exchange of experience between departments with focus on adequate surgical technique and careful hemostasis.

Postinflammatory, acquired atresia of the external auditory meatus is a relatively rare consequence of chronic otitis media or recurrent external otitis with an annual incidence of 0.6 cases per 100,000 inhabitants. Primary and late results after operative treatment of this condition in 53 ears over 27 years are presented. Perioperative findings are described, and an outline of applied surgical technique is given. Six patients had bilateral involvement. The male-to-female ratio was 1:2, median age at surgery was 46 years, and the median follow-up period was 5 years (range, 4 mo to 13 y). In 11% of the cases, recurrent atresia developed. Early operation is recommended, because cholesteatoma behind the atresia was found in 9%. Hearing improvement has been considerable after removal of the atresia with primary closure of airbone gap within 20 dB in 90% of the cases.

Children start school with differing levels of skills. Thus, children of different social origin have different probabilities of educational success right from the start of their school career. This paper analyses how the gap in language abilities of children with different social backgrounds develops from age three to five. A focus lies on the question whether pre-school education can help to close this gap. The data of the UK Millennium Cohort Study (MCS) show that children's score on a standardized vocabulary test strongly depends on their parents' education. These social differences remain stable or even increase slightly over the two-year period. Using fixed effect models, it is demonstrated that children of higher educated parents can improve their vocabulary more strongly than children whose parents have a lower educational level. Participation in an early education institution positively affects the vocabulary development of children with lower educated parents while there is no significant pre-school effect for children of higher educated parents. The results indicate that pre-school attendance does not lead to a catching-up process of children with lower educated parents. But without pre-school attendance, the gap between children of higher and lower educated parents widens even further.

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The paper compares several generational groups of Turkish children in Germany with respect to cognitive skills and German language skills at an early age. Empirically, children of inter-marriages outperform the other groups of Turkish children in both tests while children with a first generation mother and a second generation father score worse than all others. All group differences regarding children’s cognitive skills can be explained by the families’ socio-economic status and educational resources. In contrast, with respect to children’s language skills also parents’ endowment with receiving country specific resources (e.g., parental German language proficiency) needs to be taken into account.

A lot of research has been devoted to explaining immigrants' acquisition of the language of the receiving country. However, less attention has been paid to explaining the acquisition of the heritage language among children of immigrants. The most important determinant for young children is exposure to the language. Language exposure can occur in various contexts, such as within the family, during preschool, through peers or via media. Our empirical analysis therefore explores which of these contexts is most statistically significant for the acquisition of the heritage language among children of Turkish immigrants. Using data from the project Preschool Education and Educational Careers among Migrant Children, we show that all contexts are important at different age levels but the acquisition of the heritage language is mainly determined by the exposure to it within the family.

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