Provenance of Jurassic Sediments from Yuqia Sandstone-Type Uranium Deposits in the Northern Margin of Qaidam Basin, China and Its Implications for Uranium Mineralization

The Yuqia uranium deposit is a newly discovered sandstone-type uranium deposit in the northern margin of the Qaidam Basin. Concerning the sources of sediment in the basin, most scholars have focused on the study of Cenozoic sediment sources in the northern part of the basin, rather than on the study of Jurassic provenance and its implications for uranium mineralization. In this paper, the Jurassic sandstones in the area were selected for petrography, petrogeochemistry and electron microprobe analysis (EPMA), and the significance of sedimentary provenance and uranium metallogeny were further discussed, based on the previous data of detrital zircon chronology. It is reported here for the first time that coffinite and pitchblende are the main contributors. Independent uranium minerals in the region mainly occur in strawberry pyrite, xenotime, and margins or of quartz. The rocks in the source area, Jurassic sandstones, were mainly formed under the tectonic setting of the active continental margin; however, the sediments are mainly derived from the Indosinian and Paleozoic granitoids exposed in the northern margin of the Qaidam Basin. The uranium-rich granites in the source area led to the preconcentration of uranium in the sandstone of the target layer, and the uranium was brought into the ore-bearing target layer through uranium-bearing oxygenated water. The reduction reaction occurred under the action of reducing matter, and finally, the U6+ was reduced to U4+ in the formation of coffinite and pitchblende.

Effect of Different Cavity Disinfectants on Microleakage

BACKGROUND Cavity disinfectants are frequently used for the elimination of bacteria that remain in the cavity, which are shown as the cause of secondary caries. However, its effect on microleakage from the tooth-restoration interface is still under investigation. The purpose of this study was to compare and evaluate the effects of the use of three different cavity disinfectants on microleakage in Class V composite restorations. METHODS For this study, 28 permanent third molar teeth without caries and restoration were used. Class V cavities of 4 mm x 3 mm x 3 mm were prepared on the buccal surfaces of each tooth. The teeth were randomly divided into 4 groups, with 7 teeth in each group. No cavity disinfectant was applied to the teeth in group 1. Tubulicid Red Label (Dental Therapeutics AB, Sweden) cavity disinfectant was applied to the 2nd group teeth, Cavity Cleanser (BISCO Inc., USA) cavity disinfectant to the 3rd group teeth, and Oxygenated Water (Dermosept, Turkey) cavity disinfectant to the 4th group teeth. Composite resin with universal adhesive and nanohybrid filler was applied to all samples in the groups in accordance with the recommendations of the manufacturers, and finishing and polishing processes were performed. Then, the thermal cycle (NOVA, Konya, Turkey) procedure was applied. After the restorations were covered with nail polish, they were kept in a 5 % basic fuchsin solution. The teeth were cut vertically in the buccolingual direction and examined with a stereomicroscope at x 40 magnification. The results were statistically evaluated with Kruskal-Wallis and Mann-Whitney U tests. RESULTS When the microleakage scores were compared between the control group and the groups treated with Tubulicid Red Label (p:0.204), Cavity Cleanser (p:0.204) and Oxygenated Water (P: 0.788), it was determined that there was no statistically significant difference (P > 0.05). CONCLUSİONS It was determined that different cavity disinfectants applied in Class V cavities did not have a negative effect on microleakage and the closest results to the control group were seen in the group where cavity cleanser disinfectant containing 2 % chlorhexidine digluconate was applied. KEY WORDS Cavity Disinfectants, Class V Cavity, Microleakage.

Retracing hypoxia in Eckernförde Bight (Baltic Sea)

An increasing number of dead zoning (hypoxia) has been reported as a consequence of declining levels of dissolved oxygen in coastal oceans all over the globe. Despite substantial efforts a quantitative description of hypoxia up to a level enabling reliable predictions has not been achieved yet for most regions of societal interest. This does also apply to Eckernförde Bight (EB) situated in the Baltic Sea, Germany. The aim of this study is to dissect underlying mechanisms of hypoxia in EB, to identify key sources of uncertainties, and to explore the potential of existing monitoring programs to predict hypoxia by developing and documenting a workflow that may be applicable to other regions facing similar challenges. Our main tool is an ultra-high spatially resolved general ocean circulation model based on a code framework of proven versatility in that it has been applied to various regional and even global simulations in the past. Our model configuration features a spacial horizontal resolution of 100 m (unprecedented in the underlying framework which is used in both global and regional applications) and includes an elementary representation of the biogeochemical dynamics of dissolved oxygen. In addition, we integrate artificial “clocks” that measure the residence time of the water in EB along with timescales of (surface) ventilation. Our approach relies on an ensemble of hindcast model simulations, covering the period from 2000 to 2018, designed to cover a range of poorly known model parameters for vertical background mixing (diffusivity) and local oxygen consumption within EB. Feed-forward artificial neural networks are used to identify predictors of hypoxia deep in EB based on data at a monitoring site at the entrance of EB. Our results consistently show that the dynamics of low (hypoxic) oxygen concentrations in bottom waters deep inside EB is, to first order, determined by the following antagonistic processes: (1) the inflow of low-oxygenated water from the Kiel Bight (KB) – especially from July to October – and (2) the local ventilation of bottom waters by local (within EB) subduction and vertical mixing. Biogeochemical processes that consume oxygen locally are apparently of minor importance for the development of hypoxic events. Reverse reasoning suggests that subduction and mixing processes in EB contribute, under certain environmental conditions, to the ventilation of the KB by exporting recently ventilated waters enriched in oxygen. A detailed analysis of the 2017 fish-kill incident highlights the interplay between westerly winds importing hypoxia from KB and ventilating easterly winds which subduct oxygenated water.

Immunotherapy Using Oxygenated Water and Tumor-Derived Exosomes Potentiates Antitumor Immune Response and Attenuates Malignancy Tendency in Mice Model of Breast Cancer

Breast cancer is one of the most common type of tumor and the leading cause of death in the world’s female population. Various therapeutic approaches have been used to treat tumors but have not led to complete recovery and have even damaged normal cells in the body. Moreover, metastatic tumors such as breast cancer are much more resistant to treatment, and current treatments have not been very successful in treating them and remain a challenge. Therefore, new approaches should be applied to overcome this problem. Given the importance of hypoxia in tumor survival, we aimed to test the antitumor effects of oxygenated water to decrease hypoxia along with tumor-derived exosomes to target tumor. The purpose of administering oxygenated water and tumor exosomes was to reduce hypoxia and establish an effective immune response against tumor antigens, respectively. For this purpose, the breast cancer mice model was induced using the 4T1 cell line in Balb/c mice and treated with oxygenated water via an intratumoral (IT) and/or intraperitoneal (IP) route and/or exosome (TEX). Oxygenation via the IT+IP route was more efficient than oxygenation via the IT or IP route. The efficiency of oxygenation via the two routes along with TEX led to the best therapeutic outcome. Antitumor immune responses directed by TEX became optimized when systemic (IP) and local (IT) oxygenation was applied compared to administration of TEX alone. Results demonstrated a significant reduction in tumor size and the highest levels of IFN-γ and IL-17 and the lowest levels of IL-4 FoxP3, HIF-1α, VEGF, MMP-2, and MMP-9 in the IT+IP+TEX-treated group. Oxygenated water on the one hand could reduce tumor size, hypoxia, angiogenesis, and metastasis in the tumor microenvironment and on the other hand increases the effective immune response against the tumor systemically. This therapeutic approach is proposed as a new strategy for devising vaccines in a personalized approach.

Effect of Hot Rolling on the Intrinsic Properties of Aluminium-Titanium Bonded by PTFE/ C -Cyanoacrylate

The concern of this study shows the effect of hot rolling on the properties of a composite sheet prepared from aluminium bonded to titanium metals sandwiching PTFE (Du Pont)/graphite emulsion in perfluoro kerosene. The metals were soaked in hot oxygenated water and dried at 80 °C for 5 - 10 minutes to create a thin film of oxide. The metals were bonded with cyanoacrylate blended to the polymer emulsion that applied to the oxidized surface of the clean metals. Two coated surfaces sandwich the polytetrafluoroethylene (PTFE)/graphite emulsion followed by ‎hot-rolling. The rolling process was matched at 500- 560 °C (≈ 150 °C, over the melting point of the PTFE) under a pressure of 150-200 KPa. The obtained composite sheet was annealed at 550 °C to remove any residual stresses. Results revealed that upon cooling, the mix microphase would separate with the OH radicals on the metal surface and the CF displaced away. The temperature and time of cyanoacrylate application enhanced the extent of adhesion to create a homogeneous composite metal sheet. The effect of the hot rolling conditions was ascribed to the PTFE underactivity and incompatibility. Rolling imparts squeezing of the metals and changes the intrinsic properties. Linear thermal expansion coefficient of the composite sheet confirms partial diffusion of the soft metal in the harder one across the adhesive. The applied technique deforms the PTFE particles without inhibiting the adhesion strength of the cyanoacrylate. The prepared sheet has physical properties that would be suitable for bailiwick and structural ‎application.

MICROCRUSTACEAN ASSEMBLAGES AND WATER QUALITY IN A HIGH-ALTITUDE POND IN SOUTH BRAZIL (PARANÁ)

The aim of this study was to assess the abundance and richness of microcrustacean, and water physical and chemical characteristics of a high-altitude pond in the Serra do Mar at State of Paraná. Water samples were collected quarterly between August 2015 and August 2016. Environmental conditions of pond were characterized by small pond size and depth, cold and well oxygenated water, and neutral or slightly acid pH. Mean total microcrustacean density was 945.0 ind m-3, whereas total taxon richness was 3.40. The most abundant species was Tropocyclops prasinus. The small size and the isolament of the pond, and the low temperatures were related to the low species richness and abundance. This study is unprecedented to the State of Paraná. Future studies attempt to understand the environmental conditions and distribution of microcrustaceans from high-altitude ponds.

20% Citric Acid its effectiveness as a chelator in endodontic treatment of temporary teeth

In endodontics, the use of a final irrigantthat has properties such as antimicrobial effect, tissue dissolution and biocompatibility is essential, since toxins are the main cause of the development and persistence of a pulp and periapical lesion. Objective: To evaluate the antimicrobial capacity of 20% citric acid as a chelating solution used during the treatment of pulpectomies in temporary dental organs. Materials and methods: The study population included 30 patients from the Pediatric Dentistry Clinical of the Facultad de Estomatologia of the Universidad Autonoma de San Luis Potosí (UASLP). The participants had an age range between 3 to 9 years of age and in terms of gender 15 male and 15 female, after information consent of the minors and signature of the informed consent of the parents. Results: Citric acid at 20% showed a reduction of microorganisms from 2.5 to 6.0 CFU (Colony Forming Units) while oxygenated water, although presenting a reduction for colony forming units, was only 1 to 2 UFC. Conclusion: Citric acid is a good irrigant, but it should continue studies.

Retracing Hypoxia in Eckernförde Bight (Baltic Sea)

In recent years, upwelling events of low-oxygenated deep water have been repeatedly observed in Eckernförde Bight (EB) situated in the Baltic Sea, Germany. Many of these events were related to massive fish-kill incidents – with negative consequences for commercial fisheries and tourism. The aim of this study is to dissect underlying mechanisms and to explore the potential of existing monitoring programs to predict these events. Our main tool is an ultra-high spatially resolved general ocean circulation model which drives an elementary representation of the biogeochemical dynamics of dissolved oxygen (dubbed MOMBE and EckO2, respectively). In addition, we integrate artificial clocks that measure the residence time of the water in EB along with timescales of (surface) ventilation. We present an ensemble of hind cast model simulations, covering the period from 2000 up to 2018, designed to cover a range of poorly known model parameters for vertical background mixing (diffusivity) and local oxygen consumption within EB. Our results indicate that the dynamics of low (hypoxic) oxygen concentrations in bottom waters deep inside EB is, to first order, determined by the following antagonistic processes: (1) the inflow of low-oxygenated water from the Kiel Bight (KB) – especially from July to October and (2) the local ventilation of bottom waters by local (within EB) subduction and vertical mixing. Biogeochemical processes that consume oxygen locally, are apparently of minor importance for the development of hypoxic events. Reverse reasoning suggests that subduction and mixing processes in EB contribute, under certain environmental conditions, to the ventilation of the KB by exporting recently-ventilated waters enriched in oxygen. A detailed analysis of the 2017 fish-kill incident highlights the interplay between westerly winds importing hypoxia from KB and ventilating easterly winds which subduct oxygenated water. Finally, we explore the capabilities of – comparably computationally cheap – feed-forward artificial neuronal networks to forecast hypoxia deep in EB based on data at a monitoring site at the entrance of EB.

Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland

The Goldenville horizon in the Baie Verte Peninsula is an important stratigraphic horizon that hosts primary (Cambrian to Ordovician) exhalative magnetite and pyrite and was a chemical trap for younger (Silurian to Devonian) orogenic gold mineralization. The horizon is overlain by basaltic flows and volcaniclastic rocks, is intercalated with variably coloured argillites and cherts, and underlain by mafic volcaniclastic rocks; the entire stratigraphy is cut by younger fine-grained mafic dykes and coarser gabbro. Lithogeochemical signatures of the Goldenville horizon allow it to be divided into high-Fe iron formation (HIF; >50% Fe2O3), low-Fe iron formation (LIF; 15-50% Fe2O3), and argillite with iron minerals (AIF; <15% Fe2O3). These variably Fe-rich rocks have Fe-Ti-Mn-Al systematics consistent with element derivation from varying mineral contributions from hydrothermal venting and ambient detrital sedimentation. Post-Archean Australian Shale (PAAS)-normalized rare earth element (REE) signatures for the HIF samples have negative Ce anomalies and patterns similar to modern hydrothermal sediment deposited under oxygenated ocean conditions. The PAAS-normalized REE signatures of LIF samples have positive Ce anomalies, similar to hydrothermal sediment deposited under anoxic to sub-oxic conditions. The paradoxical Ce behaviour is potentially explained by the Mn geochemistry of the LIF samples. The LIF have elevated MnO contents (2.0-7.5 weight %), suggesting that Mn from hydrothermal fluids was oxidized in an oxygenated water column during hydrothermal venting, Mn-oxides then scavenged Ce from seawater, and these Mn-oxides were subsequently deposited in the hydrothermal sediment. The Mn-rich LIF samples with positive Ce anomalies are intercalated with HIF with negative Ce anomalies, both regionally and on a metre scale within drill holes. Thus, the LIF positive Ce anomaly signature may record extended and particle-specific scavenging rather than sub-oxic/redox-stratified marine conditions. Collectively, results suggest that the Cambro-Ordovician Taconic seaway along the Laurentian margin may have been completely or near-completely oxygenated at the time of Goldenville horizon deposition.