31 research outputs found
A self-potential investigation of submarine massive sulfides: Palinuro Seamount, Tyrrhenian Sea
The self-potential (SP) method detects naturally occurring electric fields which may be produced by electrically conductive mineral deposits such as massive sulfides. Recently, there has been increasing interest in applying this method in a marine environment to explore for seafloor massive sulfide (SMS) deposits which may contain economic resources of base and precious metals. While SMS sites that are associated with active venting and are not buried under sediment cover are known to produce an SP signal, the effectiveness of the method at detecting inactive and sediment-covered deposits remained an outstanding question. We built an instrument capable of recording SP data in a marine setting. We carried out a test of the instrument at the Palinuro Seamount in the Tyrrhenian Sea. Palinuro is one of only a few known sites containing an SMS occurrence which is buried under sediment and not associated with active hydrothermal venting, although diffuse seepage of hydrothermal fluids is known to occur at the site. Elevated electric field strengths recorded in and near the site of previously drilled massive sulfide samples are on the order of 1–3 mV/m. A second zone of high field strengths was detected by us to the north of the drilling area where gravity coring later confirmed the existence of massive sulfides. Our observations indicate that an SP signal can be observed at the site of SMS mineralization even when the mineralized zone is shallowly buried and active hydrothermal venting is not present. These observations could aid in the planning of future marine research expeditions which use the SP method in the exploration of seafloor massive sulfides
Синтез полиномиальных регуляторов с учетом возмущений
Статья посвящена исследованию компенсационного метода синтеза полиномиальных регуляторов с учетом изменений в управляемости и наблюдаемости замкнутой системы. Проанализирован алгоритм получения регуляторов по методу желаемой передаточной функции, позволяющий получить близкие показатели качества как по управлению, так и по возмущению
Alterations of Gab2 signalling complexes in imatinib and dasatinib treated chronic myeloid leukaemia cells
The atypical kinase RIOK1 promotes tumor growth and invasive behavior
Despite being overexpressed in different tumor entities, RIO kinases are hardly characterized in mammalian cells. We investigated the role of these atypical kinases in different cancer cells. Using isogenic colon-, breast- and lung cancer cell lines, we demonstrate that knockdown of RIOK1, but not of RIOK2 or RIOK3, strongly impairs proliferation and invasiveness in conventional and 3D culture systems. Interestingly, these effects were mainly observed in RAS mutant cancer cells. In contrast, growth of RAS wildtype Caco-2 and Bcr-Abl-driven K562 cells is not affected by RIOK1 knockdown, suggesting a specific requirement for RIOK1 in the context of oncogenic RAS signaling. Furthermore, we show that RIOK1 activates NF-κB signaling and promotes cell cycle progression. Using proteomics, we identified the pro-invasive proteins Metadherin and Stathmin1 to be regulated by RIOK1. Additionally, we demonstrate that RIOK1 promotes lung colonization in vivo and that RIOK1 is overexpressed in different subtypes of human lung- and breast cancer. Altogether, our data suggest RIOK1 as a potential therapeutic target, especially in RAS-driven cancers
Axitinib and sorafenib are potent in tyrosine kinase inhibitor resistant chronic myeloid leukemia cells
Using self-potential to explore for submarine massive sulfides: Palinuro Seamount, Tyrrhenian Sea
Syndiospecific polymerization catalysts for styrene based on rare earth metal half-sandwich complexes
Microplastics in two German wastewater treatment plants: Year-long effluent analysis with FTIR and Py-GC/MS
Microplastics (MP) have been recorded in various environments around the globe. For a better understanding of distribution patterns and for providing a basis for risk assessments, detailed data on MP concentrations and polymer compositions are required. This study investigated the effluents of two German wastewater treatment plants (WWTP) monthly over one year, in order to better understand their temporal input of MP into the receiving river systems. MP item data down to 11 μm were obtained by means of Fourier Transform Infrared (FTIR) spectroscopy under the application of an improved polymer database. Complementary mass data were obtained by pyrolysis gas chromatography–mass spectrometry (Py-GC/MS) (for one WWTP). Both FTIR and Py-GC/MS analysis revealed a homogeneous polymer composition over the year, with a general dominance of polyolefins. Elevated MP item and mass concentrations (maximum: 3 × 104 items m−3 and 3.8 × 103 μg m−3) were observed during winter months and were accompanied by either heavy rainfall (increased discharge and total organic carbon) or elevated turbidity values. These observations emphasize the need for the assessment of background parameters in future MP monitoring studies. By providing monthly data over one year on MP items and masses in WWTP effluents, this study helps enhancing the understanding of temporal MP dynamics and can act as a valuable reference point for future assessments
Microplastics in Waste Water Treatment Plants: Monthly analysis with FTIR and Py-GC/MS and methodological improvements
Microplastics (MP) were shown to be present in various environments around the world. In order to better understand distribution patterns and to provide a solid basis for risk assessments of this organic pollutant, comprehensive datasets on MP concentrations and chemical compositions are needed. This study focussed on the effluents of two German wastewater treatment plants (WWTP) and investigated the temporal input of MP into the receiving river systems by performing a year-long sampling campaign with monthly sampling events. MP item data (minimum size: 11 μm) were generated using Fourier Transform Infrared (FTIR) spectroscopy, under the application of an improved polymer database. The database adaptation allowed for an improved data quality, as it counteracted matrix interferences due to residual plant material on measurement filters. Beside item data, complementary MP mass data were gained by the application of pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) (for one WWTP). Both item and mass data showed homogeneous polymer compositions over the sampling year, generally dominated by polyolefins. Elevated MP item and mass concentrations occurred during winter months, and were accompanied by either heavy rainfall (resulting in increased discharge), total organic carbon or elevated turbidity values. These findings underline the necessity for the integration of background parameters in MP monitoring studies. Finally, by providing monthly data over one year on MP masses and items, this work contributes to the current knowledge on temporal MP dynamics in WWTP effluents, and can therefore be a useful baseline for future monitoring studies