Radiologische Analyse eines Knochendefektmodells zur Lokalapplikation von Medikamenten am osteoporotisch induzierten Rattenfemur - Eine Pilotstudie

Die Osteoporose gehört aufgrund ihrer Häufigkeit weltweit zu den Volkskrankheiten. Durch den Anstieg der Lebenserwartung wird die Inzidenz der Osteoporose und damit der Osteoporose-bedingten Frakturen in den kommenden Jahren weiter ansteigen. Da-her zählt die Verbesserung der Prophylaxe, Diagnostik und Therapie der Osteoporose zu den medizinischen Herausforderungen des 21. Jahrhunderts. In der vorliegenden Studie wurde erstmals der Effekt einer lokalen Applikation von Os-teoprotegerin (OPG) in den Knochenspalt bei der Frakturheilung im Modell der osteo-porotischen Ratte (Wistar-Hannover) untersucht. Die Studie diente zusätzlich als Pilot-studie zur Überprüfung der Eignung der Methodik für den nachfolgenden Hauptver-such. Eingeschlossen wurden drei Versuchsgruppen (ovarektomierte Ratten ohne OPG (OV-OPG), ovarektomierte Ratten mit OPG (OV+OPG), nicht-ovarektomierte Ratten ohne OPG (Kontrollgruppe), jeweils n = 10). Den Ratten wurde im rechten Femur ein Osteotomiespalt (1 mm) gesetzt, in den das OPG über eine Trägermatrix (Spongos-tan®) implantiert wurde. Als Osteosynthese diente ein Fixateur externe. Nach vier Wo-chen wurden die Tiere euthanasiert. Die Frakturbereiche wurden post mortem mittels peripherer quantitativer Computertomografie (pQCT), bildgebenden Verfahren (Nativ-Röntgen, Mikro-Computertomografie (µCT) und histologischer (Toluidinblau-, Masson-Goldner-Trichrom-Färbung) Verfahren analysiert. Die Anlage des Fixateur externe und die Platzierung des Spongostans® in den Osteo-tomiespalt verlief problemlos. Die mehrheitlich bei ovarektomierten Rattten auftreten-den Narkoseprobleme ließen sich am ehesten auf eine langsamere Verstoffwechselung der i. m. applizierten Narkoemedikamente bei höherem Körperfettanteil zurückführen. Ein bei 10 % der Tiere auftretender Versatz der Femurenden unterstreicht die Wichtig-keit von regelmäßigen Röntgenkontrollen der regelrechten Lage des Fixateur externe. Die hochauflösenden 3D µCT-Aufnahmen stellten das Gewebe im Frakturspalt detail-liert dar. Eine deutlichere Durchbauung des Spongostans® und eine Ausbildung von Knochenspangen kennzeichneten die bessere Knochenwundheilung in der OV+OPG-Gruppe. Die pQCT-Befunde deuten an, dass OPG bei der Osteoporose die Knochen-fläche und Knochenmasse, nicht jedoch die Knochendichte erhöht. Die histologische Analyse bestätigte die µCT-Befunde und erlaubte einen detaillierten Einblick in die Ge-schehnisse im Knochenspalt (Zellinfiltration, Angiogenese, Durchbau des Spongos-tans®, Bildung von Knochengewebe und Knochenspangen, fehlende Nekrosen). Die geringe Subgruppenbesetzung sowie der enge Versuchszeitraum von vier Wochen limitierte die Aussagekraft der Pilotstudie. Vermutlich lassen sich die Aussagen zur Wirksamkeit des OPG in der geplanten Hauptstudie durch eine Erhöhung der Ver-suchstierzahl sowie einer Verlängerung des Versuchszeitraums validieren

Телекоммуникационные системы для мониторинга и охраны лесных ресурсов России

Излагаются результаты разработки и полномасштабного внедрения телекоммуникационных систем семейства "Ясень" для мониторинга и охраны лесных ресурсов России, составляющих более четверти ресурсов мира. Описаны модификации систем семейства "Ясень" для федерального, регионального уровней и для подразделений, в которых предусмотрена интеграция каналов связи (наземных, радио, сотовых, спутниковых), документированная связь, геоинформационный мониторинг и сопровождение подвижных объектов

Sedimentary facies reconstruction and kinematic restoration of an Upper Permian tight gas field, north-western Germany

This study of a tight gas reservoir, located at ~4200 metres depth in the Upper Rotliegend II (Upper Permian) of north-western Germany, includes a geological framework model for the sedimentary facies distribution, which is strongly influenced by the structural grain. Research focused on unravelling the structural and sedimentary complexity of Permian (Rotliegend) tight gas fields in Central Europe requires multidisciplinary studies combining tectonic-stratigraphic interpretation of three-dimensional seismic reflection, wireline log and core data, laboratory analysis, numerical modelling and field based analogue studies. Reservoir rocks in the study area are of fluvio-aeolian origin, and include dune, fluvial and wet to dry interdune deposits. Dune and minor sandflat deposits represent the most important gas reservoir rocks of the Upper Rotliegend II. Source rocks are Westphalian coals, and the top seal is provided by Zechstein evaporites. Detailed analysis of palaeo-topography, fault activity and accommodation for strata of Permian age (Rotliegend and Zechstein groups) indicate that local depocentres developed within small-scale, fault-controlled transtensional sub-basins. Synsedimentary halfgraben development and fault activity were identified during Upper Rotliegend II deposition. Many Upper Rotliegend structures were reactivated during the Triassic, Jurassic and Cretaceous, often developing enhanced offsets and lateral extent. As a consequence, much of the original Rotliegend structures and stratigraphy were significantly displaced, ultimately re-arranging the location of former Rotliegend depocentres and associated tight gas reservoir facies. This tectonic overprint hampers the prediction of potential Rotliegend reservoirs, emphasizing the necessity of palaeo-environmental restorations in areas with multi-phase tectonic histories. In addition, the sedimentary environment and involved sedimentary processes were only punctually reconstructed from core material and log data. A field analogue study in Panamint Valley, California, United States, was carried out to improve the understanding of the interactions between the sedimentary systems and tectonic processes in graben / halfgraben structures similar to those in the Upper Rotliegend of north-western Germany. The comparison shows that both study areas are characterized by (i) synsedimentary transtensional tectonics resulting in elongated graben structures with large-scale, bounding fault zones, (ii) a fault-controlled (palaeo-)topography, which is one of the key controlling mechanisms of the sediment facies distribution, comprising different types of alluvial fans, dunes, wet and damp interdune sandflats, and ephemeral dry lake deposits, and (iii) very similar sediment sources comprising clastic input from fault zone footwalls and input from volcanics. Consequently, the field analogue-based study provides a detailed model of the sedimentary facies for the tight gas reservoir in Germany prior to multi-phase tectonic overprinting, including the composition and distribution of aeolian sandstone reservoirs and their relation to fault-induced topography. For a better understanding of the multi-phase tectonic overprinting that influenced the primarily good reservoir rocks, a sequential 2D retro-deformation of the study area with focus on the temporal differentiation of salt diapirism and its relation to regional tectonic phases was carried out. Backstripping considers sedimentation, decompaction, fault-related deformation, salt movement, thermal subsidence and isostasy to gain a better understanding of the link between tectonics and reservoir diagenesis. The modeling results of this study indicate that reactive diapirism started during the Lower Buntsandstein, followed by active diapirism starting in the Lower Keuper accompanied by salt piercement of the overburden. Since the Lower Cretaceous, the salt rises by passive diapirism. From isopach maps, fluid inclusion studies, and K/Ar ages a clear linkage between the study area’s structural evolution and the timing of diagenetic processes can be observed

Sedimentary facies reconstruction and kinematic restoration of an Upper Permian tight gas field, north-western Germany

This study of a tight gas reservoir, located at ~4200 metres depth in the Upper Rotliegend II (Upper Permian) of north-western Germany, includes a geological framework model for the sedimentary facies distribution, which is strongly influenced by the structural grain. Research focused on unravelling the structural and sedimentary complexity of Permian (Rotliegend) tight gas fields in Central Europe requires multidisciplinary studies combining tectonic-stratigraphic interpretation of three-dimensional seismic reflection, wireline log and core data, laboratory analysis, numerical modelling and field based analogue studies. Reservoir rocks in the study area are of fluvio-aeolian origin, and include dune, fluvial and wet to dry interdune deposits. Dune and minor sandflat deposits represent the most important gas reservoir rocks of the Upper Rotliegend II. Source rocks are Westphalian coals, and the top seal is provided by Zechstein evaporites. Detailed analysis of palaeo-topography, fault activity and accommodation for strata of Permian age (Rotliegend and Zechstein groups) indicate that local depocentres developed within small-scale, fault-controlled transtensional sub-basins. Synsedimentary halfgraben development and fault activity were identified during Upper Rotliegend II deposition. Many Upper Rotliegend structures were reactivated during the Triassic, Jurassic and Cretaceous, often developing enhanced offsets and lateral extent. As a consequence, much of the original Rotliegend structures and stratigraphy were significantly displaced, ultimately re-arranging the location of former Rotliegend depocentres and associated tight gas reservoir facies. This tectonic overprint hampers the prediction of potential Rotliegend reservoirs, emphasizing the necessity of palaeo-environmental restorations in areas with multi-phase tectonic histories. In addition, the sedimentary environment and involved sedimentary processes were only punctually reconstructed from core material and log data. A field analogue study in Panamint Valley, California, United States, was carried out to improve the understanding of the interactions between the sedimentary systems and tectonic processes in graben / halfgraben structures similar to those in the Upper Rotliegend of north-western Germany. The comparison shows that both study areas are characterized by (i) synsedimentary transtensional tectonics resulting in elongated graben structures with large-scale, bounding fault zones, (ii) a fault-controlled (palaeo-)topography, which is one of the key controlling mechanisms of the sediment facies distribution, comprising different types of alluvial fans, dunes, wet and damp interdune sandflats, and ephemeral dry lake deposits, and (iii) very similar sediment sources comprising clastic input from fault zone footwalls and input from volcanics. Consequently, the field analogue-based study provides a detailed model of the sedimentary facies for the tight gas reservoir in Germany prior to multi-phase tectonic overprinting, including the composition and distribution of aeolian sandstone reservoirs and their relation to fault-induced topography. For a better understanding of the multi-phase tectonic overprinting that influenced the primarily good reservoir rocks, a sequential 2D retro-deformation of the study area with focus on the temporal differentiation of salt diapirism and its relation to regional tectonic phases was carried out. Backstripping considers sedimentation, decompaction, fault-related deformation, salt movement, thermal subsidence and isostasy to gain a better understanding of the link between tectonics and reservoir diagenesis. The modeling results of this study indicate that reactive diapirism started during the Lower Buntsandstein, followed by active diapirism starting in the Lower Keuper accompanied by salt piercement of the overburden. Since the Lower Cretaceous, the salt rises by passive diapirism. From isopach maps, fluid inclusion studies, and K/Ar ages a clear linkage between the study area’s structural evolution and the timing of diagenetic processes can be observed