Morphology and Histology of Lattice-like Ossified Epaxial Tendons in Psittacosaurus(Dinosauria:Ceratopsia)

Epaxial tendons play an important role in the study of the musculoskeletal system and locomotory style of dinosaurs. Although the ossified epaxial tendon lattice is fairly well known in Iguanodontoidea, only recently has knowledge of this complex been extended to ceratopsians. This study concerns the gross morphology and microstructure of the tendon lattice in Psittacosaurus, a basal ceratopsian. As in the neoceratopsian Chasmosaurus, the ossified tendons of Psittacosaurus form a three -layered, lattice-like structure. The microstructure of the tendons in large psittacosaur individuals retains an early stage of ossification, as in juvenile birds and nestling hadrosaurs, suggesting a slow developmental rate of ossification of the tendons in psittacosaur ontogeny. Comparative study indicates that a lattice-like arrangement of three-layered epaxial tendons is widely distributed in Cerapoda. This pattern also extends to Ankylosauria, implying a similar pattern of the epaxial muscles through the ornithischian clade. In addition, comparison with crocodiles implies that the different morphology of ossified tendons in dinosaurs may be associated with adaptive aspects of their paleobiology, not simply a side effect of skeletal ossification. In contrast to the short tendons in quadrupedal Chasmosaurus and Protoceratops, the elongated tendons in Psittacosaurus may be related to the bipedal locomotion characteristic of this taxon.

加拿大不列颠哥伦比亚省温哥华岛纳奈莫群的帆翼龙类化石(英文)

An unusual jaw found in a calcite nodule from Collishaw Point,Hornby Island,British Columbia(off the east coast of Vancouver Island)represents the first definitive

翼龙类和驰龙类尾的前关节突和脉弧棒的趋同演化及翼龙类和鸟类尾部肌肉退化的平行模式(英文)

The caudal morphology of dromaeosaurid dinosaurs and most "rhamphorhynchoid" pterosaurs is a striking example of convergent evolution.

Anatomical Study of Cretaceous,Permineralized,Bennettitalean Fossils from Heilongjiang Province,NE China

Well-preserved Cretaceous trunk fragments of Cycadeoidea(Cycadeoidaceae)were recently found in Keshan County,Heilongjiang Province,Northeast China.These fossils represent important evidence of the distribution of this group of plants in East Asia.In these trunk fragments,the stem cortices and leaf bases with cones are preserved.The leaf bases are rhombic with cones infrequently distributed among leaf bases.The cortex is broad and consists of fundamental parenchyma cells,numerous secretory ducts and C-shaped leaf traces with adaxial secondary xylem and abaxial secondary phloem.The genus Cycadeoidea,which is widely distributed in the Cretaceous deposits of East Asia,North America and Western Europe,was an important component of Cretaceous floras.Bennettitalean trunk fossils with well-preserved anatomical structures are rarely known from China.These fossils are important for studies of the evolution of genus Cycadeoidea and for stratigraphic correlation.

Hydration and Slag-attack Resistance of Dense MgO-dolomite Refractory Grains in Relation to Their Phase Composition and Microfabric

This work aims at optimizing densification parameters as well as resistance to hydration and slag attack of MgO-Dolomite refractory grains, processed from Egyptian dolomitc-magnesite raw material up to firing for 1-4 h at 1400-1600 ℃, in relation to their phase composition and microfabric. Minor amount of natural ilmenite mineral (0-2 wt%), separated from Egyptian black sands was used in doping the dolomitc-magnesite.

A New Species of Rhodoleia(Hamamelidaceae) from the Upper Pliocene of West Yunnan, China and Comments on Phytogeography and Insect Herbivory

In Europe, fossil fruits and seeds of Rhodoleia（Hamamelidaceae） have been described from the Upper Cretaceous to the Miocene, whereas no fossil record of Rhodoleia has been reported in Asia, where the modern species occur.Herein, 21 fossil leaves identified as Rhodoleia tengchongensis sp.nov.are described from the Upper Pliocene of Tengchong County, Yunnan Province, Southwest China.The fossils exhibit elliptic lamina with entire margins, simple brochidodromous major secondary veins, mixed percurrent intercostal tertiary veins, and looped exterior tertiaries.The leaf cuticle is characterized by pentagonal or hexagonal cells, stellate multicellular trichomes, and paracytic stomata.The combination of leaf architecture and cuticular characteristics suggests that the fossil leaves should be classified into the genus Rhodoleia.The fossil distributions indicate that the genus Rhodoleia might originate from Central Europe, and that migrated to Asia prior to the Late Pliocene.Additionally, insect damage is investigated, and different types of damage, such as hole feeding, margin feeding, surface feeding, and galling, are observed on the thirteen fossil leaves.Based on the damage frequencies for the fossil and extant leaves, the specific feeding behavior of insects on Rhodoleia trees appears to have been established as early as the Late Pliocene.The high occurrence of Rhodoleia insect herbivory may attract the insect-foraging birds, thereby increasing the probability of pollination.

Late Cretaceous Biostratigraphy Planktonic Foraminifera of the Farokhi Formation, Iran

The Farokhi Formation is one of the informal Central Iran formations, which is located in the NW Tabas township. The Tabas area is a part of the Central Iran sedimentary basin which is located in the Yazd Province. The Farokhi stratigraphic section is located 7 km northwest from Farokhi village (33°54' 9''N and 54°52'48''E). The Bazyab, Debarso, Haftoman and Choopanan formations are well-exposed in the studied area. In this study, the Farokhi Formation is investigated in the Farokhi stratigraphic section with regard to planktonic foraminifera. The Farokhi Formation is mainly composed of thick-bedded limestones with ammonoids, thin-bedded limestone with silicified echinoids and ichnofossils, marls with nodular cherts, spherical corals and bivalves. Biostratigraphy of the Farokhi Formation at type section has been concentrated in view of planktonic foraminifera. Thickness of this formation is 251 meters. The lower and upper contacts of studied formation with Haftoman and Choopanan formations are respectively conform and inconsistent. In view of late research, it has been identified that 28 planktonic foraminifera species have a place with 9 genera in edge of 6 biozones, for example: 1) Globotruncanita elevata Partial Range Zone. 2) Globotruncana ventricosa Interval Zone. 3) Globotruncanita stuartiformis Partial Range Zone. 4) Globotruncana aegyptiaca Interval Zone. 5) Gansserina gansseri Interval Zone. 6) Contu-sotruncana contusa Interval Zone. Finally based on this research, Early Campanian-Late Maastrichtian ages for the Farokhi Formation at type locality have been determined.

Influence of Fresh Water on Microbubble Generation in an Airlift Column Applied to Aquaculture: Extraction Capacity

Bubble flows consist a liquid phase and a gaseous phase dispersed as bubbles. They occur in nature and in many industrial applications, such as oil transportation in pipelines and steam generators for power generation. Due to large difference in density between gas and liquid, the flottability force causes bubbles to rise, which in turn can generate overall motion and agitation in liquid. This use of gravity as a flow driver, which is specific to disperse phase systems, is used in process engineering (bubble columns and gasosiphon) to sparingly promote mixing and exchange between gas and liquid. In many applications, bubbles are used to agitate a liquid in order to promote mixing and transfers. This work is devoted to study of hydrodynamics of a bubble column. Experimentally, we have determined properties fluctuations of velocities inside the aquarium of rising homogeneous bubbles for different bubble sizes and vacuum rates. The interfacial area between gas and liquid phase is a crucial factor for mass transfer in bubble columns. The molecular exchange between a given volume of gas and water can be enhanced by formation of smaller bubbles, leading to a larger gas-liquid interface. This work presents the various physical phenomena that apply to bubbles, as well as associated dimensionless numbers. A state art of Micro-Bubble Generators (MBG) is then presented, presenting systems using various phenomena such as cavitation, electrolysis, or shear.

Sedimentary facies analysis of a high-frequency,small-scale,peritidal carbonate sequence in the Lower Jurassic of the Tripolis carbonate unit (central western Crete,Greece):Long-lasting emergence and fossil laminar dolocretes horizons

Abstract The study examines a Lower Jurassic （late Liassic） cyclic lagoonal-peritidal stratigraphic unit outcropping in central western Crete （Tripolis unit）, which corresponds to the eastern （internal） part of the mainland Gavrovo-Tripotis platform, the most significant external platform of the Hetlenides. The studied Tripolis carbonate sequence consists of meter-scale, shallowing-upward successions of restricted inner- carbonate platform facies, including cyclically repeated subtidal, intertidal and supratidal facies, that are separated by erosion surfaces （elementary cycles）. Each cycle starts with relatively open-marine facies, which are overlain by shallower, more restricted facies （tidal fiat progradation）. The lithofacies association includes dotomitic intraclastic-peloidal-bioclastic wackestones-packstones/floatstones and grainstones/rudstones dominated by a restricted shallow-marine fauna （bivalves, gastropods, ostracods and seldom benthic fora- minifers）, representing a shaUow subtidal to intertidal, moderately high-energy environment within an inner- platform setting （peritidal environment to restricted lagoon）. This lithofacies association has been intermit- tently subaeriaUy exposed and has undergone diagenetic processes in an inter- or supratidal environment, exhibiting features of vadose diagenesis and pedogenesis due to long-lasting exposure along certain horizons. The peritidat facies are capped by dolocretes controlled by root-activities （laminar dolocretes, petoi- dat-pisoid dolocretes and massive dotocretes）, marking the end of each depositional cycle, and, thus, dis- tinguishing the successive episodes of a prolonged subaerial exposure period and birth of pateosol horizons. Dotocretes consist a diagenetic facies, characterized by several vadose and pedogenic fabrics, including fenestral cavities with geopetal structures, ＂flower spar＂ to blocky sparry cement in primary pores, micritic coatings, crudely pelleted watts, atveotar-septat texture, infilts of rootlet moulds, inter-granular micritic bridges, meniscus cement, sinuous desiccation cracks, circum-granular cracking and in-situ brecciation. The stratigraphic distribution of the cyclothems, suggests relative sea-level control on the peritidal cyclicity controlled by uniform tectonic subsidence and eustasy （attocyctic processes）, in an inner- ramp-to-shelf carbonate setting with tidal fiat and restricted lagoon depositional environment. However, a combination of attocyctic with autocyctic processes controtting accommodation space and sediment accumutation, shoutd be atso taken in consideration. The studied high-frequency cyctes are interpreted to have been formed during the fatting stage and correspond to towstand systems tract （LST） sediments, which consists part of a regressive peak of the Lower/htiddte Jurassic Transgressive-Regressive Facies Low Frequency Cycte （2nd order）. Due to the absence of massive evaporites, dolomitization has been attributed to reflux of stightly increased-satinity marine fluids （i.e. penesatine）, that are driven into the undertying tagoonat-peritidat carbonate sediments during periods of tong term sea-fever fatl in a marginal marine setting.