Minor Remnants Research Articles

Histomorphological assessment of the germanium-doped calcium phosphate ceramics on reparative osteogenesis in rabbits with systemic osteoporosis

Bone fractures are mostly urgent in nature, complex in pathogenetic, diagnostic and therapeutic aspects, and reparative osteogenesis is multimodal and depends on the balanced and reciprocal interaction of many factors. The results of histological studies for osteoreplacement of bone defects in rabbits with systemic osteoporosis are presented. The purpose of the work is histomorphological evaluation of bone regenerates after osteoreplacement with germanium-doped hydroxyapatite ceramics in rabbits with secondary osteoporosis. Experimental osteoporosis in rabbits (n=18) was induced by administration of 0.4% dexamethasone solution. In animals of the experimental group, bone defects were replaced with granules of hydroxyapatite ceramics doped with germanium, and in animals of the control group, they healed under a blood clot. Histological sections were made on a rotary microtome with a thickness of 5 to 10 μm and stained with Weigert's iron hematoxylin and 1% alcohol-based eosin solution (manufactured by Diapath, Italy). On the 60th day of reparative osteogenesis in the animals of the experimental group, the site of the bone defect was flled with compact bone tissue with minor remnants of spongy bone tissue. Slightly expanded Haversian canals were noted. In the control group, the defect site was flled with coarse and spongy bone tissue. Bone beams of various thicknesses with a small number of osteoblasts and single walled osteocytes were visualized. A signifcant number of osteocyte lacunae were empty due to the process of osteocyte lysis. Haversian canals are signifcantly dilated with a small number of vessels. Also, lacunae of bone tissue resorption and acellular areas were observed on histological specimens. Histomorphological assessment of bone regenerates confrms the realization of osteoconductive, osteointegrative and osteoinductive properties of calcium-phosphate ceramics doped with germanium in conditions of osteoporotic fractures of tubular bones. Keywords: systemic osteoporosis, bone fractures, cancellous and compact bone tissue, histological sections, histomorphological changes, rabbits.

Effect of Heat Treatment on the Microstructure and Mechanical Properties of 18Ni-300 Maraging Steel Produced by Additive-Subtractive Hybrid Manufacturing.

The present work investigates the effectiveness of two heat treatment cycles-solution treatment + aging (STA) and direct aging (DA)-on optimizing the microstructure and enhancing the mechanical properties of 18Ni-300 maraging steel (300 MS) produced by additive-subtractive hybrid manufacturing (ASHM). The STA treatment led to a fully martensitic microstructure with minor remnants of the cellular substructures associated with the solidification conditions in ASHM. DA resulted in some reverted austenite and partial dissolution of the cellular morphologies into shorter fragments. Despite the contrasting microstructures, the tensile strength and the macro- and micro-hardness were comparable between STA and DA conditions. By contrast, the potential for improving the ductility was higher with the DA heat treatment. This is attributed to the higher reverted austenite content in the samples treated by DA, i.e., up to a maximum of 13.4% compared to less than 3.0% in the STA samples. For the DA sample with the highest reverted austenite content of 13.4%, the highest local and global fracture strain values of 30.1 and 5.9 ± 0.6% were measured, while the respective values were 23.4 and 4.4 ± 0.1% for the corresponding STA sample. This work suggests that DA of 300 MS produced by ASHM is sufficient to achieve comparable hardness and tensile strength to STA, whilst maintaining reasonable ductility. Avoiding the solution treatment cycle, with its appreciably higher temperatures, could benefit the dimensional stability and surface quality that are important for ASHM of 300 MS parts.

Exploratory mapping of structures controlling mineralization in Southeast Nigeria using high resolution airborne magnetic data

High resolution airborne magnetic data of some regions of Southeast Nigeria were analyzed to map structures controlling mineralization. Such data can be used for mineral assessment programs, surficial geologic boundaries, hydrocarbon exploration at reconnaissance stage, mapping of hydrothermally altered rock zones and geologic structures. First and second vertical derivatives, upward continuation, source edge detection, analytical signal, Centre for Exploration Targeting (CET) and standard Euler deconvolution operations were done to delineate the spatial distributions and depths to the different magnetic sources. The enhanced maps showed major and minor magnetic anomaly centres in the Lower Benue Trough (LBT) and Ikom-Mamfe Rift (IMR) characterized by thin (151–745 m) sedimentation. Also, within these areas there exist some isolated pockets of intermediate depths (745–1634 m) occurring in the neighborhood of these magnetic anomalies. The Calabar Flank (CF) characterized by minor remnants of post-Cretaceous intrusions has sedimentation of over 6126 m in some locations. The 2000 m upward continued TMI map revealed the existence of major deep-seated weak zones believed to have originated during the rifting episode connected with the formation of the Benue Trough. The abundance of intrusive bodies in the LBT and IMR render these parts of the study area unattractive for hydrocarbon exploration. Nevertheless, they possess high base metal mineralization potential while CF is a favorable site for hydrocarbon search.

Balancing Purification and Ultrastructure of Naturally Derived Bone Blocks for Bone Regeneration: Report of the Purification Effort of Two Bone Blocks.

The present publication reports the purification effort of two natural bone blocks, that is, an allogeneic bone block (maxgraft®, botiss biomaterials GmbH, Zossen, Germany) and a xenogeneic block (SMARTBONE®, IBI S.A., Mezzovico-Vira, Switzerland) in addition to previously published results based on histology. Furthermore, specialized scanning electron microscopy (SEM) and in vitro analyses (XTT, BrdU, LDH) for testing of the cytocompatibility based on ISO 10993-5/-12 have been conducted. The microscopic analyses showed that both bone blocks possess a trabecular structure with a lamellar subarrangement. In the case of the xenogeneic bone block, only minor remnants of collagenous structures were found, while in contrast high amounts of collagen were found associated with the allogeneic bone matrix. Furthermore, only island-like remnants of the polymer coating in case of the xenogeneic bone substitute seemed to be detectable. Finally, no remaining cells or cellular remnants were found in both bone blocks. The in vitro analyses showed that both bone blocks are biocompatible. Altogether, the purification level of both bone blocks seems to be favorable for bone tissue regeneration without the risk for inflammatory responses or graft rejection. Moreover, the analysis of the maxgraft® bone block showed that the underlying purification process allows for preserving not only the calcified bone matrix but also high amounts of the intertrabecular collagen matrix.

Safety and completeness of using indocyanine green videoangiography combined with digital subtraction angiography for aneurysm surgery in a hybrid operating theater.

This study aimed to evaluate the safety and completeness of using intraoperative indocyanine green videoangiography (ICGV) combined with intraoperative angiography (IOA) for aneurysm clipping in a hybrid operating room (hOR). All patients who underwent microsurgical clipping in the hOR were identified from prospectively maintained neurosurgical databases. Medical charts and operative videos with ICGV and IOA were reviewed to determine the adequacy of clipping, and clinical and angiographic outcomes were retrospectively analyzed. Fifty-four cerebral aneurysms (ruptured, 31; unruptured, 23) in 50 patients (mean age, 59.4 ± 10.9 y; M:F, 22:28) were evaluated with ICGV and IOA during clipping. Additional IOA led to a clip adjustment during surgery in 9/54 (16.7%) aneurysms for which ICGV had been initially performed. Post-clip perforator compromise occurred in two (3.7%) cases, with a patient with an unruptured aneurysm experiencing permanent injury (grade 3 hemiparesis) and patient with a ruptured aneurysm experiencing transient deficit. Post-clip parent vessel stenosis occurred in one (1.9%) case; however, an ischemic event did not occur because the flow patency was identified by IOA. No other patients with unruptured aneurysms developed new neurologic deficits at discharge. Favorable outcomes (Glasgow Outcome Score [GOS], 4 or 5) were observed in 26/31 patients with ruptured aneurysms. Five patients had unfavorable outcomes (GOS, 2 or 3) from the initial insult. Post-treatment angiography within 1week showed complete occlusion in 52 (96.3%) aneurysms and minor remnants in two (3.7%) aneurysms. Using combined ICGV and IOA in a hOR may improve the safety and completeness of microsurgical aneurysm clipping.

Accelerated Soft and Hard Tissue Healing In Extraction Sockets Augmented With Bone Allograft and Amnio- Fluid, Clinical and Histological Report of Ten Cases

Preservation of the dental extraction sockets through bone grafting has been a key procedure to maintain the volumetric aspect of the bone walls. This has been proven successful in bone preservation for future implant insertion or prosthetic treatment. Several materials of bone allograft, xenografts, synthetics and membranes were successful in socket preservation however the healing duration and the outcome of bone formed differs. Ten patients selected with posterior extraction sockets for the augmentation procedure, the bone graft mass mixed with Amnio-Spark fluid (Salvin Dental Specialties, Charlotte, NC, USA) and the wound secured with sutures and left to heal with no covering membrane. Post-operative visits scheduled at two, four and twelve weeks’ intervals for monitoring of the healing and core biopsies were harvested from the augmented extraction sockets and examined histologically at the twelve’s week. At two weeks, there was considerable formation of tissue covering the bone graft material which continued to progress into keratinized tissue in four weeks. Core bone biopsies taken at twelve weeks demonstrated a pattern of viable bone formation with minor remnants of the bone graft material. This case series will demonstrate the effectiveness of the amnio- fluid in rapid formation of gingival tissue on top of the augmented extraction socket wounds. Additionally, it will histologically confirm expedited bone remodeling into the extraction socket following the augmentation

Pedology of archaeological soils in tells of the Judean foothills, Israel

Tells (archaeological mounds) predominantly consist of poorly consolidated to unconsolidated sediments, and soils that are highly anthropogenic. This study examines pedogenic processes related to carbonate mobilization in tells in comparison with their peripheral soils (reference soil profiles). The key objective of this study is to test the hypothesis that tell deposits evolve through concurrent processes of sedimentation and pedogenesis (synlithogenic pedogenesis), and further explain it. Case studies are presented from three tells in semi-arid and Mediterranean climatic zones of the Levant. The methods applied included field survey, analyses of particle size distribution, pH, %CaCO3 and organic carbon content, and soil micromorphology. Soils of the tells contain miscellaneous cultural materials that derive mainly from degraded mud bricks, pottery and burnt wood. Chemical data show basic pH values, high CaCO3 content, and minor amounts of organic carbon. Field observations and lab analyses both indicate high similarity amongst the tells and their reference soil profiles. Buried tell soils show same characteristics as near-surface soils. However, the reference soil profiles show incipient horizonation, slightly darker colours, and more developed structure. Micromorphology of both the tells and the reference profiles show cohesively welded peds in a vughy microstructure, groundmass with an open porphyric c/f-related distribution, and discontinuous carbonate recrystallization. Relative rates of soil formation in the tells can be estimated when archaeological records are established. Contrary to the tells, the reference soil profiles show lower porosity and only minor remnants related to earth construction materials. We classify the soils of the studied tells as archaeological Calcareous Anthraltic Xerorthents. The correlative WRB classification would be Calcic Urbic Technosols (Archaic). The anthropogenic materials are as calcareous as the natural soils, but due to human action, carbonates in the tells are distributed differently. Based on these observations, ancient human actions and the dry climate have led to very little mobilization and accumulation of carbonates. The information provided in this study adds to the pedological understanding of archaeological environments. Specifically, it can be useful for the study of site formation processes of tells.

Pollution distribution in floodplain structure visualised by electrical resistivity imaging in the floodplain of the Litavka River, the Czech Republic

Shape and position of modern polluted sediment bodies in the floodplain internal structure can provide insight into past and future erosional/deposition behaviour of fluvial systems. Extensive field works needed for such studies can be mitigated by the use of geophysical imaging, originally developed for engineering practice but still rather sparsely used in floodplain research. We demonstrate the performance of electrical resistivity tomography (ERT), dipole electromagnetic profiling (DEMP), and X-ray fluorescence spectroscopy for identification of subsurface sediment bodies of contrasting lithology, age, and pollution status; we found minor remnants of unpolluted (ancient) floodplain segments that would likely have been overlooked in arbitrary “blind” sampling. Pollution chemostratigraphy of floodplains based on the concentrations of certain risk elements can be affected by post-depositional migration. We thus identified signatures related to mining and smelting that are carried by coarser particles (gangue, fly ash) not expected to undergo post-depositional translocations in alluvium: the local enrichment factor of Zr (LEF Zr) and mass-specific magnetic susceptibility (χ). The LEF Zr differentiated pre-mining floodplain sediments which originated from erosion of Zr-rich catchment loess soils from Zr-poor, gangue-derived material. χ exhibits a step-like increase above the threshold value of approximately 25·10−8 m3/kg in severely polluted sediments; we assign that χ step to the replacement of charcoal and wood by coke in smelting technology during the late 19th century. The shape of the unpolluted sedimentary bodies, as well as bodies of historically changing pollution extent, indicate considerable recent lateral river instability. A mild aggradation flattened the floodplain surface and prevented the identification of buried sedimentary bodies by surface topography, but did not restrict the power of the geophysical imaging.

Osteoinduction and -conduction through absorbable bone substitute materials based on calcium sulfate: in vivo biological behavior in a rabbit model.

Calcium sulfate (CS) can be used as an antibiotically impregnated bone substitute in a variety of clinical constellations. Antibiotically loaded bone substitutes find specific application in orthopedic and trauma surgery to prevent or treat bone infections especially in relation to open bone defects. However, its use as a structural bone graft reveals some concerns due to its fast biodegradation. The addition of calcium carbonate and tripalmitin makes CS formulations more resistant to resorption leaving bone time to form during a prolonged degradation process. The aim of the present study was the evaluation of biocompatibility and degradation properties of newly formulated antibiotically impregnated CS preparations. Three different types of CS bone substitute beads were implanted into the tibial metaphysis of rabbits (CS dihydrate with tripalmitin, containing gentamicin (Group A) or vancomycin (Group B); Group C: tobramycin-loaded CS hemihydrate). Examinations were performed by means of x-ray, micro-computed tomography (micro-CT) and histology after 4, 6, 8 and 12 weeks. Regarding biocompatibility of the formulations, no adverse reactions were observed. Histology showed formation of vital bone cells attached directly to the implanted materials, while no cytotoxic effect in the surrounding of the beads was detected. All CS preparations showed osteogenesis associated to implanted material. Osteoblasts attached directly to the implant surface and revealed osteoid production, osteocytes were found in newly mineralized bone. Group C implants (Osteoset®) were subject to quick degradation within 4 weeks, after 6-8 weeks there were only minor remnants with little osteogenesis demonstrated by histological investigations. Group A implants (Herafill®-G) revealed similar degradation within atleast 12 weeks. In contrast, group B implants (CaSO4-V) were still detectable after 12 weeks with the presence of implant-associated osteogenesis atlatest follow-up. In all of these preparations, giant cells were found during implant degradation on surface and inside of resorption lacunae. None of the analyzed CS preparations triggered contact activation. All implants demonstrated excellent biocompatibility, with implants of Group A and B showing excellent features as osteoconductive and -inductive scaffolds able to improve mechanical stability.

Endoscopic submucosal dissection for superficial Barrett's esophageal cancer in the Japanese state and perspective.

The incidence of Barrett's esophageal cancer is one of the most rapidly increasing among all cancers in the West, and it is also expected to increase in Japan. The optimal treatment for early Barrett's esophageal cancer remains controversial. En bloc esophagectomy with regional lymph node dissection has been considered the standard therapy. Endoscopic therapies are currently being evaluated as alternatives to esophagectomy because they can provide the least postoperative morbidity and the best quality of life. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) allow for removal of visible lesions and histopathologic review of resected tissue, which help in diagnostic staging of the disease. EMR is limited with respect to resection size, and large lesions must be resected in several fragments. Piecemeal resection of lesions is associated with high local recurrence rates, probably because of minor remnants of neoplastic tissue being left in situ. ESD provides larger specimens than does EMR in patients with early Barrett's neoplasia. This in turn allows for more precise histological analysis and higher en bloc and curative resection rates, potentially reducing the incidence of recurrence. Detailed endoscopic examination to determine the invasion depth and spread of Barrett's esophageal cancer is essential before ESD. The initial inspection is usually conducted with white-light imaging followed by narrow-band imaging. The ESD procedure is similar to that for lesions in other parts of the gastrointestinal tract. However, the narrow space of the esophagogastric junction and contraction of the lower esophageal sphincter sometimes disturb the visual field and endoscopic control. Skilled endoscope handling, sometimes including retroflexion, is required during ESD for Barrett's esophageal cancer. Previous reports have shown that ESD achieves en bloc resection in >80% of lesions. Although promising short-term results are reported, a long-term, large-scale study is required for better understanding of ESD for Barrett's esophageal cancer.

Evolution of the lithospheric mantle beneath the southeastern North China Craton: Constraints from mafic dikes in the Jiaobei terrain

Two stages of mafic dikes with ages of ~117–116Ma and ~95–87Ma, respectively, are identified in the Jiaobei terrain based on zircon U–Pb ages. The Early Cretaceous mafic-intermediate dikes (ECMDs) and Late Cretaceous mafic dikes (LCMDs) show distinct geochemical and isotopic features. The ECMDs are enriched in large ion lithophile elements (LILE, Rb, Sr, Ba, U and Th) and light rare earth elements (LREE, La, Ce, Pr, Nd, Sm and Eu) with a strong depletion in high field strength elements (HFSE, Nb, Ta, Ti and P). They show uniformly high (87Sr/86Sr)i (0.70841–0.71387), low εNd(t) values (−18.1 to −13.2), positive (206Pb/204Pb)i (17.07–17.90) and negative εHf(t) (−21.0 to −6.1) values. These rocks were derived from partial melting of an enriched lithospheric mantle, and the enrichment of the mantle source resulted from source metasomatism imparted by the melts generated from remelting of the subducted lower crust of the Yangtze Craton (YC). In contrast, the LCMDs show lower SiO2 (41.5–50.1wt.%), lack of HFSE depletion and are depleted in whole rock Nd and zircon Hf isotope. They are interpreted to have sourced from a newly accreted depleted lithospheric mantle generated through continuous erosion of older enriched lithospheric mantle by asthenospheric upwelling, leaving out minor remnants of the older mantle in the newly accreted lithospheric mantle. The geochemical and isotopic characteristics reported in our study demonstrate that the lithospheric mantle beneath the southeastern North China Craton (NCC) was generally enriched during the Early Cretaceous (~120Ma) and the mechanism of the enrichment may be related to source metasomatism caused by the subducted lower crust of the YC. However, in Late Cretaceous, the lithospheric mantle beneath southeastern NCC was highly heterogeneous, which might be related to asthenospheric non-uniform erosion. The ~116–87Ma marks the transition from enriched lithospheric mantle to depleted asthenospheric mantle.

Genome Analyses of Icelandic Strains ofSulfolobus islandicus, Model Organisms for Genetic and Virus-Host Interaction Studies

The genomes of two Sulfolobus islandicus strains obtained from Icelandic solfataras were sequenced and analyzed. Strain REY15A is a host for a versatile genetic toolbox. It exhibits a genome of minimal size, is stable genetically, and is easy to grow and manipulate. Strain HVE10/4 shows a broad host range for exceptional crenarchaeal viruses and conjugative plasmids and was selected for studying their life cycles and host interactions. The genomes of strains REY15A and HVE10/4 are 2.5 and 2.7 Mb, respectively, and each genome carries a variable region of 0.5 to 0.7 Mb where major differences in gene content and gene order occur. These include gene clusters involved in specific metabolic pathways, multiple copies of VapBC antitoxin-toxin gene pairs, and in strain HVE10/4, a 50-kb region rich in glycosyl transferase genes. The variable region also contains most of the insertion sequence (IS) elements and high proportions of the orphan orfB elements and SMN1 miniature inverted-repeat transposable elements (MITEs), as well as the clustered regular interspaced short palindromic repeat (CRISPR)-based immune systems, which are complex and diverse in both strains, consistent with them having been mobilized both intra- and intercellularly. In contrast, the remainder of the genomes are highly conserved in their protein and RNA gene syntenies, closely resembling those of other S. islandicus and Sulfolobus solfataricus strains, and they exhibit only minor remnants of a few genetic elements, mainly conjugative plasmids, which have integrated at a few tRNA genes lacking introns. This provides a possible rationale for the presence of the introns.

Components and episodic growth of Precambrian crust in the Cathaysia Block, South China: Evidence from U–Pb ages and Hf isotopes of zircons in Neoproterozoic sediments

Detailed LAM-ICPMS U–Pb dating and LAM-MC-ICPMS Lu–Hf isotope analysis were carried out on zircons from nine samples of basement metamorphic rocks in the southern Cathaysia Block, South China. The chemical compositions of these metamorphic rocks and zircon morphology indicate that their protoliths were sedimentary; zircon U–Pb dating results show they mainly formed during the late Neoproterozoic. The Precambrian crust of the Cathaysia Block can be divided into two distinct tectonic domains, the Wuyishan terrane to the northeast and the Nanling-Yunkai terrane to the southwest. The nearly E–W boundary between these two terranes is also supported by geophysical, petrological and geochemical evidence, and the basement rocks of the two terranes are comprised of different components. The Wuyishan terrane is characterized by dominant Paleoproterozoic (1.86 Ga) and lesser Neoarchean magmatism, and the southern-central part of the terrane suffered strong Neoproterozoic and early Paleozoic tectonothermal reworking. The zircon data suggest that there were five important episodes of juvenile crust generation (3.6 Ga, 2.8 Ga, 2.6–2.4 Ga, 1.85 Ga and 0.8–0.7 Ga) in the Wuyishan terrane. Strong Paleoproterozoic (1.85 Ga) magmatism in northern Wuyishan and Neoproterozoic (0.8–0.7 Ga) magmatism in central and southern Wuyishan both principally involved the remelting of old crust with minor input of juvenile material. In contrast, the Nanling-Yunkai terrane contains abundant Neoarchean and Grenvillian zircons, some evidence of Mesoproterozoic activity and rare Paleo- to Meso-Archean and Neoproterozoic zircons. U–Pb ages and Hf-isotopic compositions of the detrital zircons from the late Neoproterozoic to early Paleozoic meta-sedimentary rocks in the Nanling-Yunkai area suggest that the growth of juvenile crust mainly occurred at ∼3.6 Ga, ∼3.3 Ga, 2.5–2.6 Ga, ∼1.6 Ga, ∼1.0 Ga and 0.8–0.7 Ga. Neoarchaean (2.6–2.5 Ga), Grenvillian (∼1.0 Ga) and Neoproterozoic (0.8–0.7 Ga) magmatism mainly involved the recycling of old crust. Minor remnants of ∼4.1 Ga crust may remain in the terrane. This crustal history is distinct from that of the Wuyishan terrane and analogous to those recorded for the eastern India–East Antarctic domain of northern Gondwanaland, suggesting that they probably were once linked.

Petrologic study of SJ101, a new forsterite-bearing CAI from the Allende CV3 chondrite

The forsterite-bearing Type B (FoB) CAI SJ101 consists of three major structural units: (1) light patches of sector-zoned, poikilitic Al-rich clinopyroxene (Cpx) with numerous inclusions of small spinel grains and aggregates and subordinate amounts of Mg-rich melilite (Mel) and anorthite (An) (Sp–Cpx lithology), (2) dark sinuous bands of Al-rich clinopyroxene with large (up to ∼300 × 60 μm) poikilitically enclosed euhedral forsterite (Fo) crystals (Fo–Cpx lithology), and (3) the external Cpx–Sp–An rim overlying the entire inclusion. The two major lithologies are always separated by a transition zone of clinopyroxene poikilitically enclosing both forsterite and spinel. The patches of the Sp–Cpx lithology exhibit significant textural and mineralogical variability that is size-dependent. Small patches typically consist of Cpx and spinel with minor remnants of melilite and/or its alteration products. Large patches contain Mel–An-rich cores with either equigranular–ophitic–subophitic or ‘lacy’ textures reminiscent of those in Types B or C CAIs, respectively. All silicates poikilitically enclose numerous spinel grains of identical habit. Both melilite and anorthite gradually disappear toward the boundary with the Fo–Cpx lithology. Neither the evaporation mantle of Al-rich melilite typical of other FoBs nor the Wark–Lovering rim is present. Secondary minerals include grossular, monticellite, magnetite, and a few grains of wollastonite, andradite, and nepheline. Being a rather typical FoB mineralogically and chemically, texturally SJ101 differs from other FoBs in displaying the nearly complete segregation of forsterite from spinel which occur only in the Fo–Cpx and Sp–Cpx lithologies, respectively. The complex, convoluted internal structure of SJ101 suggests that the coarse-grained Sp–An–Mel–Cpx cores and Fo–Cpx lithology represent the precursor materials of FoBs, proto-CAIs and Fo-rich accretionary rims. While the inferred chemistry and mineralogy of the Fo-rich rims are fairly typical, the high Åk content in SJ101 melilite (78.7–82.3 mol.%) implies that the SJ101 proto-CAIs represent a new type of CAIs that has not been sampled before. This type of CAIs might have formed by remelting of spinel-rich condensates. The Group II REE pattern, slightly negative δ 29Si and δ 25Mg values, and nearly solar ratios of the major elements in the bulk SJ101 suggest that its precursors, proto-CAIs and Fo-rich rims, could have formed by a non-equilibrium condensation in a closed system of solar composition somewhat depleted in a super-refractory evaporation residue. The proposed formation scenario of SJ101 invokes a non-steady cooling and condensation of the nebular gas interrupted by at least two distinct melting episodes required to account for the igneous textures of the Mel–An–Cpx-rich cores (proto-CAIs) and the Fo–Cpx lithology.

The Changing Geomorphology of Danubian Floodplains in Hungary

The once extensive floodplains along the Hungarian section of the Danube have mostly disappeared by now or have been restricted to certain reaches of the river: the Szigetkoz alluvial fan, minor remnants in the environs of Budapest and the Gemenc Forest and Beda-Karapancsa area along the southernmost Hungarian section studied here (continued on Croatian territory). From ancient times floodplains have supplied valuable economic resources and, consequently, have undergone major transformations. They are now mostly under cultivation or environmental protection. In the paper their natural and man-influenced evolution is outlined with an evaluation of perspectives for rehabilitation. Floodplain topography is evaluated and mapped for features of natural and man-made origin as well for present-day functioning in the landscape. In compliance with EU directives intensive farming is envisaged to cease over large areas of lower productivity beyond flood-control dykes and these areas will be available for rehabilitation serving conservation (through landform and habitat restoration) and flood control (through flood-water storage). Locally, traditional floodplain economy (fishing, grazing, vegetable gardens and orchards) is being restored.

El'gygytgyn impact crater, Russia: Structure, tectonics, and morphology

Abstract— The 3.6 Myr old El'gygytgyn impact crater is located in central Chukotka, northeastern Russia. The crater is a well‐preserved impact structure with an inner basin about 15 km in diameter, surrounded by an uplifted rim about 18 km in diameter. The flat floor of the crater is in part occupied by Lake El'gygytgyn, 12 km in diameter, and surrounding terraces. The average profile of the rim is asymmetric, with a steep inner wall and a gentle outer flank. The rim height is about 180 m above the lake level and 140 m above the surrounding area. An outer ring feature, on average 14 m high, occurs at about 1.75 crater radii from the center of the structure.El'gygytgyn crater is surrounded by a complex network of faults. The density of the faults decreases from the bottom of the rim to the rim crest and outside the crater to a distance of about 2.7 crater radii. Lake El'gygytgyn is surrounded by a number of lacustrine terraces. Only minor remnants are preserved of the highest terraces, 80 and 60 m above the present‐day lake level. The widest of the terraces is 40 m above the current lake level and surrounds the lake on the west and northwest sides. The only outlet of the lake is the Enmivaam River, which cuts through the crater rim in the southeast. In terms of structure, El'gygytgyn is well preserved and displays some interesting, but not well understood, features (e.g., an outer ring), similar to those observed at a few other impact structures.

PETROLEUM GEOLOGY OF MIDDLE–LATE TRIASSIC AND EARLY JURASSIC SEQUENCES IN THE SIMPSON BASIN AND NORTHERN EROMANGA BASIN OF CENTRAL AUSTRALIA

Prospective Middle–Late Triassic and Early Jurassic petroleum systems are widespread in central Australia where they have only been sparsely explored. These systems are important targets in the Simpson/Eromanga basins (Poolowanna Trough and surrounds), but the petroleum systems also extend into the northern and eastern Cooper Basin.Regional deposition of Early–Middle Triassic red-beds, which provide regional seal to the Permian petroleum system, are variously named the Walkandi Formation in the Simpson Basin, and the Arrabury Formation in the northern and eastern Cooper Basin. A pervasive, transgressive lacustrine sequence (Middle–Late Triassic Peera Peera Formation) disconformably overlies the red-beds and can be correlated over a distance of 500 km from the Poolowanna Trough into western Queensland, thus providing the key to unravelling Triassic stratigraphic architecture in the region. The equivalent sequence in the northern Cooper Basin is the Tinchoo Formation. These correlations allow considerable simplification of Triassic stratigraphy in this region, and demonstrate the wide lateral extent of lacustrine source rocks that also provide regional seal. Sheet-like, fluvial-alluvial sands at the base of the Peera Peera/Tinchoo sequence are prime reservoir targets and have produced oil at James–1, with widespread hydrocarbon shows occurring elsewhere including Poolowanna–1, Colson–1, Walkandi–1, Potiron–1 and Mackillop–1.The Early Jurassic Poolowanna Formation disconformably overlies the Peera Peera Formation and can be subdivided into two transgressive, fluvial-lacustrine cycles, which formed on a regional scale in response to distal sea level oscillations. Early Jurassic stratigraphic architecture in the Poolowanna Trough is defined by a lacustrine shale capping the basal transgressive cycle (Cycle 1). This shale partitions the Early Jurassic aquifer in some areas and significant hydrocarbon shows and oil recoveries are largely restricted to sandstones below this seal. Structural closure into the depositional edge of Cycle 1 is an important oil play.The Poolowanna and Peera Peera formations, which have produced minor oil and gas/condensate on test respectively in Poolowanna–1, include lacustrine source rocks with distinct coal maceral compositions. Significantly, the oil-bearing Early Jurassic sequence in Cuttapirrie–1 in the Cooper Basin correlates directly with the Cycle–1 oil pool in Poolowanna–1. Basin modelling in the latter indicates hydrocarbon expulsion occurred in the late Cretaceous (90–100 Ma) with migration into a subtle Jurassic age closure. Robust Miocene structural reactivation breached the trap leaving only minor remnants of water-washed oil. Other large Miocene structures, bound by reverse faults and some reflecting major inversion, have failed to encounter commercial hydrocarbons. Future exploration should target subtle Triassic to Jurassic–Early Cretaceous age structural and combination stratigraphic traps largely free of younger fault dislocation.

Textural evidence of peperites inside pillow lavas at Acicastello Castle Rock (Mt. Etna, Sicily)

Globular and microglobular peperites, with mingled sediment in millimetric to decimetric domains, are described from inside pillow lavas at Acicastello Castle Rock, Mt. Etna, Sicily for the first time. The peperites now comprise basalt and minor remnants of fine-grained detrital material, with smectite and zeolite crystallised during late hydrothermal activity. We propose that peperites formed when the magma, ascending towards the surface, intruded and intermixed with the unconsolidated wet Pleistocene bluish marly clays of the substrate. Subsequently they were transported by the uprising magma from the source region towards the surface, where they are preserved in pillow lavas.

In situ delivery of cytokines by genetically engineered Lactococcus lactis.

The development of novel approaches that allow for accurate targeting of therapeutics to the bowel mucosa is a priority in the research on inflammatory bowel disease. We have engineered Lactococcus lactis to secrete soluble, fully active, correctly processed cytokines. We have used these live, recombinant strains for the in situ delivery of mouse interleukin (mIL)-2, -6 and -10 at airway mucosa or mucosa of the colon. Strains that secrete mIL-2 or mIL-6 and produce TTFC intracellular show a higher level of anti-TTFC induction in mice following intranasal inoculation. We showed that mIL-10 producing L. lactis can prevent and cure enterocolitis in mice. The daily ingestion of this strain leads to the prevention of colitis in IL-10 -/- 129 Sv/Ev mice. The repeated addition of DSS to the drinking water of Balb/c mice leads to the induction of chronic colitis with a typical mean histological score of five points. Subsequent daily treatment with 10(8) IL-10 producing L. lactis reduced the inflammation to a score of approximately 1 in 40% of the treated mice, which is a status equal to that of healthy control mice. Most other animals from the treated group only showed minor patchy remnants of the inflammation. Killing of the IL-10 producing bacteria by UV irradiation immediately prior to inoculation abrogates this therapeutic effect. Therefore it can be attributed to the active in vivo delivery of IL-10. We have further documented this by demonstrating in situ de novo synthesis of IL-10 in the colon of IL-10 -/- mice.

The gawler ranges, South Australia: an unusual volcanic massif

SUMMARY The volcanic residuals of the Gawler Ranges together form an extensive massif that in its gross morphology differs markedly from most exposures of silicic volcanic rocks. The upland developed in two stages, the first involving differential fracture‐controlled subsurface weathering, the second the stripping of the regolith. As a result, an irregular weathering front was exposed, with domical projections prominent. These bornhardts are etch forms, and they are of considerable antiquity. The differential weathering of the rock mass reflects the exploitation of various fracture systems by shallow groundwaters. Orthogonal fracture systems at various scales, sheet fractures and columnar joints control the morphology of the bornhardts in gross and in detail. The exploitation of the structural base, which was established in the Middle Protero‐zoic, probably took place throughout the Late Proterozoic and the Palaeozoic, though only minor remnants of the Proterozoic land surface remain. The major landscape features developed during the Mesozoic. The weathering which initiated the bornhardts occurred in the Jurassic or earlier Mesozoic, and the landforms were exposed in Late Cretaceous to Early Tertiary times. Though structural forms dominate the present landscape, some major and some minor landforms are best explained in terms of climatic changes of the later Cainozoic. The palaeodrainage system, established under humid conditions by the Early Tertiary, was alluviated during the Cainozoic arid phases, and salinas were formed. The sand dunes of the region also reflect this aridity.