Evaluation der potenziellen Regeneratschädigung bei der Kallusumformung nach Distraktionsosteogenese der Mandibula: Eine experimentelle Untersuchung am Tiermodell

Zusammenfassung: Ziel: Bei der Korrektur dreidimensionaler Deformitäten des Gesichtsskelettes mit der Distraktionsosteogenese werden Umformungsvorgänge des Regenerates einerseits als Bestandteil des Behandlungsplans, andererseits im Falle eines Verlustes der Kontrolle über den Distraktionsvektor vorgenommen. Die vorliegende Untersuchung hatte das Ziel, die Grenzen der Kallusmanipulation zu beurteilen. Dazu wurden die Auswirkungen komprimierender sowie dehnender Einflüsse am gleichen Regenerat untersucht. Material und Methode: Bei 15Beagle-Hunden wurde mit speziell angefertigten bidirektionalen Distraktoren eine lineare Distraktion von 10mm beidseits im Unterkieferwinkel vorgenommen. Der neu gebildete Kallus wurde in einem Schritt um 20° anguliert, was im vorliegenden Modell einer Verkürzung/Verlängerung von ca. 35% der Ausgangslänge des Regenerates gleichkommt. Die Position des Rotationszentrums erlaubte es, das Regenerat gleichzeitig zu komprimieren und zu dehnen. Die Auswirkungen dieser mechanischen Einflüsse auf die Ossifikation des Regenerates wurden nach 6 bzw. 13Wochen beurteilt und mit einer Kontrollgruppe, bei der lediglich eine lineare Distraktion durchgeführt worden war, verglichen. Ergebnisse: Die radiologischen und histologischen Untersuchungen ergaben keinen statisch signifikanten Unterschied zwischen dem komprimierten und gedehnten Regenerat. Es zeigten sich jedoch im gedehnten Sektor des Kallus Zonen unvollständiger Ossifikation nach 6-wöchiger Konsolidierungszeit. Unter stabilen Verhältnissen wurde die verzögerte Knochenheilung im weiteren Verlauf kompensiert und eine vollständige Ossifikation nach 13Wochen erreicht. Schlussfolgerung: Unter stabilen Verhältnissen kann ein durch Distraktion gebildetes frisches Regenerat in einem beträchtlichen Ausmaß umgeformt werden, ohne die knöcherne Heilung bleibend zu kompromittieren. Die Dehnung des Kallus kann jedoch zu einer Verzögerung oder dem Ausbleiben des Ossifikationsprozesses führen und sollte vermieden werden. Dies lässt sich durch eine Überkorrektur der Regeneratlänge oder durch eine graduelle Angulation während des Distraktionsvorgangs erreiche

Phylogeography of Japanese encephalitis virus:genotype is associated with climate

The circulation of vector-borne zoonotic viruses is largely determined by the overlap in the geographical distributions of virus-competent vectors and reservoir hosts. What is less clear are the factors influencing the distribution of virus-specific lineages. Japanese encephalitis virus (JEV) is the most important etiologic agent of epidemic encephalitis worldwide, and is primarily maintained between vertebrate reservoir hosts (avian and swine) and culicine mosquitoes. There are five genotypes of JEV: GI-V. In recent years, GI has displaced GIII as the dominant JEV genotype and GV has re-emerged after almost 60 years of undetected virus circulation. JEV is found throughout most of Asia, extending from maritime Siberia in the north to Australia in the south, and as far as Pakistan to the west and Saipan to the east. Transmission of JEV in temperate zones is epidemic with the majority of cases occurring in summer months, while transmission in tropical zones is endemic and occurs year-round at lower rates. To test the hypothesis that viruses circulating in these two geographical zones are genetically distinct, we applied Bayesian phylogeographic, categorical data analysis and phylogeny-trait association test techniques to the largest JEV dataset compiled to date, representing the envelope (E) gene of 487 isolates collected from 12 countries over 75 years. We demonstrated that GIII and the recently emerged GI-b are temperate genotypes likely maintained year-round in northern latitudes, while GI-a and GII are tropical genotypes likely maintained primarily through mosquito-avian and mosquito-swine transmission cycles. This study represents a new paradigm directly linking viral molecular evolution and climate

Probing RS scenarios of flavour at LHC via leptonic channels

We study a purely leptonic signature of the Randall-Sundrum scenario with Standard Model fields in the bulk at LHC: the contribution from the exchange of Kaluza-Klein (KK) excitations of gauge bosons to the clear Drell-Yan reaction. We show that this contribution is detectable (even with the low luminosities of the LHC initial regime) for KK masses around the TeV scale and for sufficiently large lepton couplings to KK gauge bosons. Such large couplings can be compatible with ElectroWeak precision data on the Zff coupling in the framework of the custodial O(3) symmetry recently proposed, for specific configurations of lepton localizations (along the extra dimension). These configurations can simultaneously reproduce the correct lepton masses, while generating acceptably small Flavour Changing Neutral Current (FCNC) effects. This LHC phenomenological analysis is realistic in the sense that it is based on fermion localizations which reproduce all the quark/lepton masses plus mixing angles and respect FCNC constraints in both the hadron and lepton sectors.Comment: 15 pages, 6 Figures, Latex fil

Kaon pair production in proton-nucleus collisions at 2.83 GeV kinetic energy

The production of non-phi K+K- pairs by protons of 2.83 GeV kinetic energy on C, Cu, Ag, and Au targets has been investigated using the COSY-ANKE magnetic spectrometer. The K- momentum dependence of the differential cross section has been measured at small angles over the 0.2--0.9 GeV/c range. The comparison of the data with detailed model calculations indicates an attractive K- -nucleus potential of about -60 MeV at normal nuclear matter density at a mean momentum of 0.5 GeV/c. However, this approach has difficulty in reproducing the smallness of the observed cross sections at low K- momenta.Comment: 7 pages, 5 figures, 1 tabl

Minimal Universal Extra Dimensions in CalcHEP/CompHEP

We present an implementation of the model of minimal universal extra dimensions (MUED) in CalcHEP/CompHEP. We include all level-1 and level-2 Kaluza-Klein (KK) particles outside the Higgs sector. The mass spectrum is automatically calculated at one loop in terms of the two input parameters in MUED: the radius of the extra dimension and the cut-off scale of the model. We implement both the KK number conserving and the KK number violating interactions of the KK particles. We also account for the proper running of the gauge coupling constants above the electroweak scale. The implementation has been extensively cross-checked against known analytical results in the literature and numerical results from other programs. Our files are publicly available and can be used to perform various automated calculations within the MUED model.Comment: 32 pages, 4 figures, 6 tables, invited contribution for New Journal of Physics Focus Issue on 'Extra Space Dimensions', the model file can be downloaded from http://home.fnal.gov/~kckong/mued

Cosmic ray tests of the D0 preshower detector

The D0 preshower detector consists of scintillator strips with embedded wavelength-shifting fibers, and a readout using Visible Light Photon Counters. The response to minimum ionizing particles has been tested with cosmic ray muons. We report results on the gain calibration and light-yield distributions. The spatial resolution is investigated taking into account the light sharing between strips, the effects of multiple scattering and various systematic uncertainties. The detection efficiency and noise contamination are also investigated.Comment: 27 pages, 24 figures, submitted to NIM

Tevatron-for-LHC Report: Preparations for Discoveries

This is the "TeV4LHC" report of the "Physics Landscapes" Working Group, focused on facilitating the start-up of physics explorations at the LHC by using the experience gained at the Tevatron. We present experimental and theoretical results that can be employed to probe various scenarios for physics beyond the Standard Model.Comment: 222 pp., additional contribution added, typos/layout correcte