Topological descriptors for 3D surface analysis

We investigate topological descriptors for 3D surface analysis, i.e. the classification of surfaces according to their geometric fine structure. On a dataset of high-resolution 3D surface reconstructions we compute persistence diagrams for a 2D cubical filtration. In the next step we investigate different topological descriptors and measure their ability to discriminate structurally different 3D surface patches. We evaluate their sensitivity to different parameters and compare the performance of the resulting topological descriptors to alternative (non-topological) descriptors. We present a comprehensive evaluation that shows that topological descriptors are (i) robust, (ii) yield state-of-the-art performance for the task of 3D surface analysis and (iii) improve classification performance when combined with non-topological descriptors.Comment: 12 pages, 3 figures, CTIC 201

Associations between preschool attendance and developmental impairments in pre-school children in a six-year retrospective survey

BACKGROUND: Many school-aged children suffer physical and mental impairments which can adversely affect their development and result in significant morbidity. A high proportion of children in western countries attend pre-school, and it is likely that the preschool environment influences the prevalence and severity of these impairments. Currently there is insufficient data available on the prevalence of these impairments and their causal associations. The influence that location of a pre-school and the duration of preschool attendance have on the prevalence of these impairments is not known. METHODS: In a retrospective survey spanning six years (1997–2002) we reviewed the records of 6,230 preschool children who had undergone routine school entry assessments. These children had been assessed utilising a modified manual of the "Bavarian Model" for school entry examinations. This model outlines specific criteria for impairments of motor, cognitive, behavioural and psychosocial functioning. Prevalence rates for physical and behavioural impairments were based on the results of these assessments. The relationship between the prevalence of impairments and the duration of preschool attendance and the location of the preschool attended was estimated utilizing logistic regression models. RESULTS: We found that 20.7% of children met the criteria for at least one type of impairment. Highest prevalence rates (11.5%) were seen for speech impairments and lowest (3.5%) for arithmetic impairments. Boys were disproportionately over represented, with 25.5% meeting the criteria for impairment, compared to 13.0% for girls. Children who had attended preschool for less than one year demonstrated higher rates of impairment (up to 19.1% for difficulties with memory, concentration or perseverance) compared to those who had attended for a longer duration (up to 11.6% for difficulties with pronouncation). Children attending preschool in an urban location had slightly elevated rates of impairment (up to 12.7%), compared to their rural counterparts (up to 11.1%). CONCLUSION: Our results demonstrate that there are high prevalence rates for physical and mental impairments among preschool children. Furthermore, children without preschool experience are a risk group for struggling with educational successes. The associations between the duration of preschool attendance and location of preschool attended and rates of impairment need replication and further exploration. Larger prospective studies are needed to examine if these relationships are causal and may therefore lend themselves to specific intervention strategies

Keep them alive! Design and Evaluation of the “Community Fostering Reference Model”

Firms host online communities for commercial purposes, for example in order to integrate customers into ideation for new product development. The success of these firm-hosted online communities depends entirely on the cooperation of a high number of customers that constantly produce valuable knowledge for firms. However, in practice, the majority of successfully implemented communities suffers from stagnation and even a decrease of member activities over time. Literature provides numerous guidelines on how to build and launch these online communities. While these models describe the initial steps of acquiring and activating a community base from scratch very well and explicitly, they neglect continuous member activation and acquistion after a successful launch. Against this background, the authors propose the Community Fostering Reference Model (CoFoRM), which represents a set of general procedures and instruments to continuously foster member activity. In this paper, the authors present the theory-driven design as well as the evaluation of the CoFoRM in a practical use setting. The evaluation results reveal that the CoFoRM represents a valuable instrument in the daily working routine of community managers, since it efficiently helps activating community members especially in the late phases of a community’s LifeCycle

Multi-dimensional modeling and simulation of semiconductor nanophotonic devices

Self-consistent modeling and multi-dimensional simulation of semiconductor nanophotonic devices is an important tool in the development of future integrated light sources and quantum devices. Simulations can guide important technological decisions by revealing performance bottlenecks in new device concepts, contribute to their understanding and help to theoretically explore their optimization potential. The efficient implementation of multi-dimensional numerical simulations for computer-aided design tasks requires sophisticated numerical methods and modeling techniques. We review recent advances in device-scale modeling of quantum dot based single-photon sources and laser diodes by self-consistently coupling the optical Maxwell equations with semiclassical carrier transport models using semi-classical and fully quantum mechanical descriptions of the optically active region, respectively. For the simulation of realistic devices with complex, multi-dimensional geometries, we have developed a novel hp-adaptive finite element approach for the optical Maxwell equations, using mixed meshes adapted to the multi-scale properties of the photonic structures. For electrically driven devices, we introduced novel discretization and parameter-embedding techniques to solve the drift-diffusion system for strongly degenerate semiconductors at cryogenic temperature. Our methodical advances are demonstrated on various applications, including vertical-cavity surface-emitting lasers, grating couplers and single-photon sources

Individual development of preschool children - prevalences and determinants of delays in Germany: a cross-sectional study in Southern Bavaria

The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1471-2431/12/188 Extent: 9p.Background: Even minor abnormalities of early child development may have dramatic long term consequences. Accurate prevalence rates for a range of developmental impairments have been difficult to establish. Since related studies have used different methodological approaches, direct comparisons of the prevalence of developmental delays are difficult. The understanding of the key factors affecting child development, especially in preschool aged children remains limited. We used data from school entry examinations in Bavaria to measure the prevalence of developmental impairments in pre-school children beginning primary school in 1997–2009. Methods: The developmental impairments of all school beginners in the district of Dingolfing- Landau, Bavaria were assessed using modified “Bavarian School Entry Model” examination from 1997 to 2009 (N=13,182). The children were assessed for motor, cognitive, language and psychosocial impairments using a standardised medical protocol. Prevalence rates of impairments in twelve domains of development were estimated. Using uni- and multivariable logistic regression models, association between selected factors and development delays were assessed. Results: The highest prevalence existed for impairments of pronunciation (13.8%) followed by fine motor impairments (12.2%), and impairments of memory and concentration (11.3%) and the lowest for impairments of rhythm of speech (3.1%). Younger children displayed more developmental delays. Male gender was strongly associated with all developmental impairments (highest risk for fine motor impairments = OR 3.22, 95% confidence interval 2.86-3.63). Preschool children with siblings (vs. children without any siblings) were at higher risk of having impairments in pronunciation (OR 1.31, 1.14-1.50). The influence of the non-German nationality was strong, with a maximum risk increase for the subareas of grammar and psychosocial development. Although children with non-German nationality had a reduced risk of disorders for the rhythm of speech and pronunciation, in all other 10 subareas their risk was increased. Conclusions: In preschool children, most common were delays of pronunciation, memory and concentration. Age effects suggest that delays can spontaneously resolve, but providing support at school entry might be helpful. Boys and migrant children appear at high risk of developmental problems, which may warrant tailored intervention strategies.Heribert L Stich, Bernhard Th Baune, Riccardo N Caniato, Rafael T Mikolajczyk and Alexander Kräme

Grenze der Operabilität bei Hauttumoren: ein Fallbeispiel

Einleitung: Das PEC der Haut ist der zweit-häufigste maligne Hauttumor. In 5% der Fälle kommt es zu einer Metastasierung, dann liegt die mediane Überlebenszeit bei 2 Jahren. Anamnese und Klinik: Ein 82-jähriger Patient stellt sich erstmals 11/2012 mit einem R1-resezierten Rezidiv eines PEC der Ohrmuschel (pT1L1) vor. Therapie: Wir führten eine Ablatio auris und Teilparotid-ektomie durch. Hier ergab sich folgende Tumorklassifikation: pT3pN2(2/3)G3L0V0, weshalb eine Radiatio eingeleitet wurde. Nach Applikation von 16Gy (5x2Gy/Wo) zeigte sich ein Rezidiv parotideal. Es erfolgte eine erneute Resektion, Restparotidektomie (M1) mit Neck diss.(N2(2/10)). Im Anschluss wurde die Radiatio bis zu einer Gesamtdosis von 66Gy fortgeführt. Bereits 3 Wochen später zeigten sich rezidivierend neue Hautmetastasen, weshalb 5-7/2012 3 Eingriffe folgten. Im Rahmen der Tumorkonferenz wurde eine palliative systemische Therapie eingeleitet und zunächst mit 2 Zyklen 5-FU (1000mg/m2 d1-5) und Cisplatin (80mg/m2 d1) begonnen. Bei klinisch sehr guter partieller Remission wurde ab dem 4. Zyklus zusätzlich Cetuximab (450mg abs.) infundiert, ab dem 9. Zyklus alleinig, wobei dieses aufgrund der Dermatotoxizität zeitweise pausiert werden mußte. Hierunter kam es 7/2014 erneut zu einem Tumorprogress, weshalb Cisplatin und 5-FU hinzugegeben wurde. Ab 4/2015 Pausierung der Therapie bei stable disease. bei Metastasierung 10/2015 wurde die Therapie, auch auf Wunsch des Patienten, bei gutem Allgemeinzustand, wieder aufgenommen. Diskussion: Die Grenze zur Palliation bei komplexen Hauttumoren ist schwer zu ziehen. Dieser Fall zeigt, dass durch eine Chemotherapie eine adäquate Lebensqualität erzielt werden kann.Der Erstautor gibt keinen Interessenkonflikt an

Patienten mit chronisch-polypöser Rezidivsinusitis leiden gehäuft unter einer Refluxerkrankung

Einleitung: Die Refluxerkrankung als eine weitere Ursache bei verschiedenen Erkankungen der NNH wird diskutiert. Unklar ist, ob es durch den Reflux zu einer direkten Sschädigung der betroffenen Schleimhäute kommt, so daß dieser Reflux auch endoskopisch, beispielweise mittels Laryngoskopie, diagnostiziert werden kann.Methodik: Mittels 2 Kanal pH Metrie (pH Response, Fa Medtronic Xomed) wurden an 20 Patienten Normwerte für den extraösophagealen Reflux (EER) bestimmt. Die Daten wurden mit denen von 20 Patienten, die sich einer NNH-Revisionsoperation bei chronischer Rezidivsinusitis (CRS) unterzogen, verglichen.Resultate: Bei Gesunden sind EER selten (Mittel 3,3 Refluxe/24 Stunden, Index für den Refluxbereich 4,1). Bei den Patienten gab es keine signifikanten Unterschiede beim EER, allerdings waren die Daten im Ösophagus teilweise um das 10-fache erhöht, so daß hier ein ausgeprägter gastroösophagealer Reflux (GERD) vorlag.Diskussion: Patienten mit CRS litten únter einem GERD, aber nicht unter EER. Das bedeutet, das diese Erkrankung nicht im Spiegelbefund diagnostiziert werden kann (fehlende Larynxbeteiligung i.S. einerr posterioren Laryngitis). Als Mechanismus der NNH Affektion sind neuroinflammatorische Reize nach ösophagealer Stimulatiion via vagaler Reflexbögen zu diskutieren

Patienten mit chronisch-polypöser Rezidivsinusitis leiden gehäuft unter einer Refluxerkrankung

Einleitung: Die Refluxerkrankung als eine weitere Ursache bei verschiedenen Erkankungen der NNH wird diskutiert. Unklar ist, ob es durch den Reflux zu einer direkten Sschädigung der betroffenen Schleimhäute kommt, so daß dieser Reflux auch endoskopisch, beispielweise mittels Laryngoskopie, diagnostiziert werden kann.Methodik: Mittels 2 Kanal pH Metrie (pH Response, Fa Medtronic Xomed) wurden an 20 Patienten Normwerte für den extraösophagealen Reflux (EER) bestimmt. Die Daten wurden mit denen von 20 Patienten, die sich einer NNH-Revisionsoperation bei chronischer Rezidivsinusitis (CRS) unterzogen, verglichen.Resultate: Bei Gesunden sind EER selten (Mittel 3,3 Refluxe/24 Stunden, Index für den Refluxbereich 4,1). Bei den Patienten gab es keine signifikanten Unterschiede beim EER, allerdings waren die Daten im Ösophagus teilweise um das 10-fache erhöht, so daß hier ein ausgeprägter gastroösophagealer Reflux (GERD) vorlag.Diskussion: Patienten mit CRS litten únter einem GERD, aber nicht unter EER. Das bedeutet, das diese Erkrankung nicht im Spiegelbefund diagnostiziert werden kann (fehlende Larynxbeteiligung i.S. einerr posterioren Laryngitis). Als Mechanismus der NNH Affektion sind neuroinflammatorische Reize nach ösophagealer Stimulatiion via vagaler Reflexbögen zu diskutieren