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REAPORÂź - Sintered open-pore glass foam as a high-strength sound absorber
The market for sound insulation products and Services, accounting for some 6000 mill. DM per annum in Germany alone, is covered to the extent of more than 90% by developments which are over 40 years old. Experts at the Fraunhofer Insdtute for Building Physics (IBP) (Director: Prof Dr. Dr. h. c. mult. Dr. E. h. mult. K. Gertis) have, together with an increasing number of small to medium-sized licensees, concentrated on the development of alternative, fibre-free absorbers (ALFA). The aim is to thus reduce noise pollution with more efficient sound-proofing technologies even in cases where traditional sound insulation materials are at a disadvantage as regards fitting and durabihty
On the number of simple cycles in planar graphs
Let CG denote the number of simple cycles of a graph G and let Cn be the maximum of CG over all planar graphs with n nodes We present a lower bound on Cn constructing graphs with at least n cycles Applying some probabilistic arguments we prove an upper bound of n We also discuss this question restricted to the subclasses of grid graphs bipartite graphs and of colorable triangulated graph
Pyeloplasty in children: is there a difference in patients with or without crossing lower pole vessel?
Introduction: Most of the children with hydronephrosis do not require any surgical intervention. However, in individual cases, irreversible loss of renal function can develop. Predictive criteria have been proven ineffective so far in determining in which children obstruction will lead to renal damage. The aim of our retrospective study was to determine the role of a crossing lower pole vessel (CV) in children undergoing pyeloplasty. Materials and methods: Between 1996 and 2003, 137 patients (age between 6weeks and 16years) with unilateral ureteropelvic junction obstruction and no associated urological pathologies underwent Anderson-Hynes dismembered pyeloplasty. A total of 112 patients were evaluated with complete data. One of the following criteria was considered to be indication for surgery in children with grade 4 hydronephrosis: differential renal function (DRF) 10% and washout patterns II or III b according to O'Reilly. We looked at the age during surgery and the kind of presentation. DRF was measured using diuretic renography preoperatively and 1year postoperatively. A postoperative change in DRF of group A (children without CV, n=84) was compared to that in group B (children with CV, n=28). Results: Median age at the time of surgery was 5months in group A compared to 23months in group B. Only in 21.4% of the children with CV compared to 60.7% without CV hydronephrosis was diagnosed by ultrasound examination antenatally. We found a preoperative DRF of 42.4%±11.2 SD in group A, and of 38.9%±11.7 SD in group B. The percentage of postoperative improvement was 3.3% in group A and 15.4% in group B. Conclusions: Children with ureteropelvic junction obstruction and CV received a delayed surgical treatment and showed a greater reduction in differential renal function preoperatively, in contrast to patients without CV. Our data show that CV is a risk factor for deterioration of renal function in children with hydronephrosis and we advocate for an early pyeloplasty in these children, especially if they have a high-grade dilatation and equivocal washout patterns in diuretic renographies. Further prospective studies are necessary in order to understand the natural history of CV and to reveal the importance of the crossing lower pole vessel as a structural anomaly lacking maturatio
Zur PunitivitÀt in Deutschland
'Ausgangsfrage ist, wieweit PunitivitĂ€t in Deutschland und anderen kontinentaleuropĂ€ischen LĂ€ndern zugenommen hat, oder ob diese Tendenz lediglich in den USA und GroĂbritannien festzustellen ist. Vor allem wurde die Situation in Deutschland betrachtet: Anhand verschiedener Quellen konnte festgestellt werden, dass die Sanktionierungspraxis in Deutschland hĂ€rter geworden ist, wobei besonders SexualstraftĂ€ter im Fokus des Interesses stehen. Oftmals ist jedoch unklar, welche Aspekte des Konstrukts PunitivitĂ€t ĂŒberhaupt angesprochen bzw. gemessen werden. Die methodische Erfassung ist bislang eher rudimentĂ€r, neuere Studien konnten zeigen, dass besonders bei Einstellungsuntersuchungen teils mit erheblichen Verzerrungen zu rechnen ist. Was die Sanktionseinstellung der Bevölkerung angeht, so weisen zahlreiche Ergebnisse auf eine gestiegene PunitivitĂ€t hin, dabei spielt besonders eine einseitige Medienberichterstattung eine wichtige Rolle. Auf der Ebene der Gesetzgebung sind im Laufe der Zeit zwar einzelne Liberalisierungstendenzen festzustellen, insgesamt ĂŒberwiegen jedoch, gerade in neuerer Zeit, deutlich GesetzesverschĂ€rfungen insbesondere im Hinblick auf SexualstraftĂ€ter. Auch anhand der Sanktionierungspraxis zeigt sich eine Zunahme hĂ€rterer Sanktionen, bei gleichzeitigem RĂŒckgang einer vorzeitigen Entlassungspraxis aus dem Strafvollzug. Insgesamt weisen somit die auf verschiedenen Ebenen gefundenen Resultate auf eine gestiegene PunitivitĂ€t in Deutschland wie auch in anderen europĂ€ischen LĂ€ndern hin, wenngleich US-amerikanische VerhĂ€ltnisse nicht erreicht werden und auch, zumindest in absehbarer Zeit, nicht zu erwarten sind.' (Autorenreferat)'The main question of the paper is whether punitivity in Germany and other continental European countries has increased, or whether such a tendency can only be observed for the USA and Great Britain. Regarding the situation in Germany, different sources showed that sanctioning became harsher, and that especially sex offenders entered the focus of interest. But often it is unclear which aspects of the construct punitivity are addressed or measured at all. In this respect survey methodology is rather rudimental, and recent studies showed that especially the measurement of punitive attitudes is flawed. Several survey results indicate an increased punitivity among the public; here, biased media reporting plays an important role. According to legislation, there are certainly some tendencies towards liberalization, but generally, especially in recent times, a strengthening of laws, particularly concerning sex offender, dominates. Furthermore, the development of sanctioning shows an increase in harsher sanctions along with a simultaneous decrease in early release practise from prison facilities. All together, results on different levels indicate an increased punitivity in Germany as well as in other European countries, although all such countries are far from the situation in the United States and it may not be expected that an equalization will occur in the foreseeable future.' (author's abstract)
A Mouse Keratin 1 Mutation Causes Dark Skin and Epidermolytic Hyperkeratosis
Chemical mutagenesis in the mouse has increased the utility of phenotype-driven genetics as a means for studying different organ systems, developmental pathways, and pathologic processes. From a large-scale screen for dominant phenotypes in mice, a novel class of pigmentation mutants was identified by dark skin (Dsk). We describe a Dsk mutant, Dsk12, which models the human disease, epidermolytic hyperkeratosis (EHK). At 2 days of age, mutant animals exhibit intraepidermal blisters and erosions at sites of trauma, and by 2 weeks of age develop significant hyperkeratosis. We identified a missense mutation in mutant animals that predicts an S194P amino acid substitution in the 1A domain of Keratin 1, a known target for human mutations that cause EHK. Dsk12 recapitulates the gross pathologic, histologic, and genetic aspects of the human disorder, EHK
Broadband sound absorber for rooms with special acoustic requirements
FĂŒr RĂ€ume, die eine mĂŒhelose und ungestörte Sprachkommunikation ermöglichen sollen, gelten erhöhte akustische Anforderungen. Als besondere Herausforderung hat sich hierbei eine DĂ€mpfung der tieffrequenten Schallanteile erwiesen. HierfĂŒr geeignete, genĂŒgend breitbandig wirksame Absorber wie Verbundplatten-Resonatoren belegen jedoch eine groĂe Wand- oder DeckenflĂ€che und sind fĂŒr viele Anwendungen zu sperrig und teuer. Das hier vorgestellte, neuartige Modul, das allseitig stabil von einem nur teilweise perforierten MetallgehĂ€use umschlossen ist, weist demgegenĂŒber nicht nur eine höhere Wirksamkeit auf, sondern eignet sich aufgrund seiner modularen Bauweise und geringer Herstellungskosten fĂŒr eine Vielzahl von Raumtypen, auch fĂŒr eine NachrĂŒstung bei laufendem Betrieb. Messwerte aus dem Hallraum und von ersten raumakustischen Sanierungen bestĂ€tigen die theoretischen Erwartungen und stellen eine praktikable Lösung fĂŒr ein allgegenwĂ€rtiges Problem der Bauphysik in Aussicht.For rooms that should allow effortless and undisturbed speech communication, increased acoustic requirements apply. The damping of low-frequency sound components has proven to be a particular challenge. However, suitable absorbers with sufficient broadband effectiveness such as composite panel resonators occupy a large wall or ceiling area and are too bulky and expensive for many applications. In contrast, the new module presented here, which is enclosed on all sides by a partially perforated metal housing, is not only more effective but, due to its modular design and low manufacturing costs, is also suitable for a large number of room types, including acoustic renovation during ongoing operation. Measured values from the reverberation room and from the first room acoustic refurbishments confirm the theoretical expectations and hold out the prospect of a practicable solution to an omnipresent problem of building physics
Toolbox for the Development of Cadastral and Registration Proclamation for Second Level Certification Program in Ethiopia
Land together with its fixtures is the single most important asset in almost all societies. In Ethiopia land is also playing a pivotal role for sustainable development. Large scale cadastral projects supporting sustainable development and increased investments are planned all over the country as part of the countr
Approximate Counting via the Poisson-Laplace-Mellin Method
Approximate counting is an algorithm that provides a count of a huge number of objects within an error tolerance. The first detailed analysis of this algorithm was given by Flajolet. In this paper, we propose a new analysis via the Poisson-Laplace-Mellin approach, a method devised for analyzing shape parameters of digital search trees in a recent paper of Hwang et al. Our approach yields a different and more compact expression for the periodic function from the asymptotic expansion of the variance. We show directly that our expression coincides with the one obtained by Flajolet. Moreover, we apply our method to variations of approximate counting, too
Review of SIS Experimental Results on Strangeness
>A review of meson emission in heavy ion collisions at incident energies
around 1 -- 2 GeV is presented. It is shown how the shape of the
spectra and the various particle yields vary with system size, with centrality
and with incident energy. A statistical model assuming thermal and chemical
equilibrium and exact strangeness conservation (i.e. strangeness conservation
per collision) explains most of the observed features.
Emphasis is put onto the study of and emission. In the framework
of this statistical model it is shown that the experimentally observed equality
of and rates at threshold corrected energies is due to a crossing of two excitation functions. Furthermore,
the independence of the to ratio on the number of participating
nucleons observed between 1 and 10 GeV is consistent with this model.
The observed flow effects are beyond the scope of this model.Comment: 10 pages, 9 figures, Strangeness 2000, V International Conference on
Strangeness in Quark Matter, July, 2000, Berkeley, Californi
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