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Cyclicity of the Lower Buntsandstein in the eastern part of the Central European Basin:implications for Early Triassic palaeogeography and for geochronological calibration

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Journal of Palaeogeography 2024年第2期13卷 252-292页

作者： Anna becker Polish Geological Institute-National Research Institute 4 Rakowiecka str.00-975 WarsawPoland

Lower Buntsandstein small—scale cycles recognized in the Central European Basin(CEB) are readily used for astrochronological calibration of the Early Triassic time scales,although they are not well studied *** borehole sections from the eastern part of the CEB,forming a south-north transect perpendicular to the basin axis,were studied in terms to better understand the depositional history of the Lower Buntsandstein developed as the Baltic Formation in the studied Polish part of the *** sedimentary facies were recognized,based on lithological and sedimentological investigations of 655.7 m of drill cores from the Otyń IG 1,Gorzów Wielkopolski IG 1 and Kamień Pomorski IG 1 *** facies can be grouped according to a lithological criterion into facies of predominantly siliciclastic lithology(including 9facies types) and facies of predominantly carbonate lithology(including 2 facies types).Facies analysis allowed to distinguish 8 facies associations of:1) alluvial fan,2) playa,3) sandy-muddy coastal plain,4)embayment and distal delta,5) lagoon,6) sand bars or shoals,7) ooidal shoals or bars,and 8) ***-upward(DC) and shallowing-upward(SC) sedimentary cycles were recognized in parts of the Baltic Formation,with DCs dominating in the southernmost located Otyń IG 1,and SCs dominating in Gorz ow Wielkopolski IG 1,located in the axial part of the *** cycles are very *** statistical significance of the sedimentary cycles is relatively low according to markov-chain analysis conducted with the phpSedistat software of Stanova et al.(2009).Analysis of small—scale cycles performed on well logs of investigated boreholes and additional boreholes in the vicinity of Otyń IG 1,implementing the earlier study of becker(2005),showed that the correlation of well-log cycles(GR cycles) and sedimentary cycles is not *** cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),refle

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

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metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar m.Patel Oseeyi I.Daudu Donald F.becker Jonathan L.Robinson Jens Nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

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A computational framework for improving genetic variants identification from 5,061 sheep sequencing data

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2332-2344页

作者： Shangqian Xie Karissa Isaacs Gabrielle becker Brenda m.murdoch Department of Animal Veterinary&Food SciencesUniversity of IdahoMoscowIDUSA Superior Farms CaliforniaUSA

Background Pan-genomics is a recently emerging strategy that can be utilized to provide a more comprehensive characterization of genetic *** calling is routinely used to combine identified variants across multiple related ***,the improvement of variants identification using the mutual support information from mul-tiple samples remains quite limited for population-scale *** In this study,we developed a computational framework for joint calling genetic variants from 5,061 sheep by incorporating the sequencing error and optimizing mutual support information from multiple samples’*** variants were accurately identified from multiple samples by using four steps:(1)Probabilities of variants from two widely used algorithms,GATK and Freebayes,were calculated by Poisson model incorporating base sequencing error potential;(2)The variants with high mapping quality or consistently identified from at least two samples by GATK and Freebayes were used to construct the raw high-confidence identification(rHID)variants database;(3)The high confidence variants identified in single sample were ordered by probability value and controlled by false discovery rate(FDR)using rHID database;(4)To avoid the elimination of potentially true variants from rHID database,the vari-ants that failed FDR were reexamined to rescued potential true variants and ensured high accurate identification *** results indicated that the percent of concordant SNPs and Indels from Freebayes and GATK after our new method were significantly improved 12%-32%compared with raw variants and advantageously found low frequency variants of individual sheep involved several traits including nipples number(GPC5),scrapie pathology(PAPSS2),sea-sonal reproduction and litter size(GRm1),coat color(RAB27A),and lentivirus susceptibility(TmEm154).Conclusion The new method used the computational strategy to reduce the number of false positives,and simulta-neously improve the identifi

关键词： Computational framework Genetic variants multiple samples Sheep

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Role of receptor tyrosine kinases in gastric cancer: New targets for a selective therapy

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World Journal of Gastroenterology 2006年第21期12卷 3297-3305页

作者： JC becker C müller-Tidow H Serve W Domschke T Pohle Department of medicine B University of münster D-48129 MünsterGermany Department of medicine A University of münster D-48129 MünsterGermany

Receptor tyrosine kinases （RTKs） such as the epidermal growth factor receptor family participate in several steps of tumor formation including proliferation and metastatic spread. Several known RTKs are upregulated in gastric cancer being prime targets of a tailored therapy. Only preliminary data exist, however, on the use of the currently clinically available drugs such as trastuzumab, cetuximab, bevacizumab, gefitinib, erlotinib, and imatinib in the setting of gastric cancer. Preclinical data suggest a potential benefit of their use, especially in combination with ＂conventional＂ cytostatic therapy. This review summarizes the current knowledge about their use in cancer therapy as well as new approaches and drugs to optimize treatment success.

关键词： Gastric carcinoma EGFR Gefitinib Trastuzumab Cetuximab Imatinib Erlotinib Bevacizumab

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micro-Structured Fiber Interferometer as Sensitive Temperature Sensor

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Photonic Sensors 2013年第3期3卷 208-213页

作者： F. C. FAVERO m. becker, R. SPITTEL m. ROTHHARDT J. KOBELKE H. BARTELT Institute of Photonic Technology (IPHT) Albert-Einstein-Strafle-9 07745 Jena Germany

We report on a fast and sensitive temperature sensor using a micro-structured or photonic crystal fiber interferometer with a high germanium doped fiber core. The wavelength sensitivity for temperature variation was as high as △λ/△T= 78 pm/℃ up to 500℃, which was 6 times more sensitive than the fiber Bragg grating temperature sensitivity of △λ/△TT= 13pm/℃ at 1550nm. The sensor device was investigated conceming the sensitivity characteristics and response time.

关键词： micro-structured optical fiber fiber interferometer fiber temperature sensor

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Design and thermodynamic analysis of a pathway enabling anaerobic production of poly-3-hydroxybutyrate in Escherichia coli

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Synthetic and Systems Biotechnology 2023年第4期8卷 629-639页

作者： Karel Olavarria marco V.becker Diana Z.Sousa mark C.m.van Loosdrecht S.Aljoscha Wahl Laboratory of microbiology Wageningen University and ResearchStippenenweg 46708 WEWageningenThe Netherlands Centre for Living Technologies Eindhoven-Wageningen-Utrecht AlliancePrincetonlaan 63584 CBUtrechtThe Netherlands Department of Biotechnology Applied Sciences FacultyDelft University of Technologyvan der Maasweg 92629 HZDelftThe Netherlands Lehrstuhl für Bioverfahrenstechnik Friedrich-Alexander-Universit¨atPaul-Gordan-Strasse 391052ErlangenGermany

Utilizing anaerobic metabolisms for the production of biotechnologically relevant products presents potential advantages,such as increased yields and reduced energy ***,lower energy dissipation may indicate that certain reactions are operating closer to their thermodynamic *** stoichiometric analyses and genetic modifications are frequently employed in metabolic engineering,the use of thermodynamic tools to evaluate the feasibility of planned interventions is less *** this study,we propose a novel metabolic engineering strategy to achieve an efficient anaerobic production of poly-(R)-3-hydroxybutyrate(PHB)in the model organism Escherichia *** approach involves re-routing of two-thirds of the glycolytic flux through non-oxidative glycolysis and coupling PHB synthesis with NADH *** complemented our stoichiometric analysis with various thermodynamic approaches to assess the feasibility and the bottlenecks in the proposed engineered *** to our calculations,the main thermodynamic bottleneck are the reactions catalyzed by the acetoacetyl-CoAβ-ketothiolase(EC 2.***.1.9)and the acetoacetyl-CoA reductase(EC 1.***.1.36).Furthermore,we calculated thermodynamically consistent sets of kinetic parameters to determine the enzyme amounts required for sustaining the conversion *** the case of the engineered conversion route,the protein pool necessary to sustain the desired fluxes could account for 20%of the whole cell dry weight.

关键词： Pathway feasibility analysis Protein cost Anaerobic metabolism Engineered pathways metabolite concentrations

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Improving the haploidization toolbox:maternal factors take the stage

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molecular Plant 2023年第4期16卷 651-653页

作者： maria Flores-Tornero Helena Sapeta Jorg D.becker Instituto de Tecnologia Quimica e Biologica Universidade Nova de LisboaAv.daRepublica2780-157OeirasPortugal

Plant breeders have a great interest in obtaining plants that are genetically homogeneous as quickly as possible,with high efficiency and at low *** approaches,including selfing or backcrossing,cannot provide *** technologies,however,offer a solution and are therefore the subject of intensive research,in particular during the last decade.

关键词： breed homogeneous quickly

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Positive predictors for gastroesophageal reflux disease and the therapeutic response to proton-pump inhibitors

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World Journal of Gastroenterology 2014年第14期20卷 4017-4024页

作者： Valentin becker Stefan Grotz Christoph Schlag Simon Nennstiel Analena Beitz Bernhard Haller Roland m Schmid Alexander meining monther Bajbouj Ⅱ. medizinische Klinik und Poliklinik Technische Universit?t München Institut für medizinische Statistik und Epidemiologie Technische Universit?t München

AIm: To identify objective and subjective predictors for the reliable diagnosis of gastroesophageal reflux disease (GERD) and the response to proton pump inhibitor (PPI) therapy.

关键词： Gastroesophageal reflux Gastroesophageal reflux disease Non-erosive reflux disease Impedance pH measurement Follow-up Therapy Proton pump inhibitor

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Derivation of moment Equations for the Theoretical Description of Electrons in Nonthermal Plasmas

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Advances in Pure mathematics 2013年第3期3卷 343-352页

作者： markus m. becker Detlef Loffhagen Leibniz Institute for Plasma Science and Technology Greifswald Germany

The derivation of moment equations for the theoretical description of electrons is of interest for modelling of gas discharge plasmas and semiconductor devices. Usually, certain artificial closure assumptions are applied in order to derive a closed system of moment equations from the electron Boltzmann equation. Here, a novel four-moment model for the description of electrons in nonthermal plasmas is derived by an expansion of the electron velocity distribution function in Legendre polynomials. The proposed system of partial differential equations is consistently closed by definition of transport coefficients that are determined by solving the electron Boltzmann equation and are then used in the fluid calculations as function of the mean electron energy. It is shown that the four-moment model can be simplified to a new drift-diffusion approximation for electrons without loss of accuracy, if the characteristic frequency of the electric field alteration in the discharge is small in comparison with the momentum dissipation frequency of the electrons. Results obtained by the proposed fluid models are compared to those of a conventional drift-diffusion approximation as well as to kinetic results using the example of low pressure argon plasmas. It is shown that the results provided by the new approaches are in good agreement with kinetic results and strongly improve the accuracy of fluid descriptions of gas discharges.

关键词： moment Equations Plasma modelling Electron Transport

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New variable stars from the photographic archive:semi-automated discoveries,attempts at automatic classification and the new field 104 Her

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Research in Astronomy and Astrophysics 2018年第8期18卷 29-40页

作者： Sergei V.Antipin Ignacio becker Alexander A.Belinski Darya m.Kolesnikova Karim Pichara Nikolay N.Samus Kirill V.Sokolovsky Alia V.Zharova Alexandra m.Zubareva P.K.Sternberg Astronomical Institute M.V.Lomonosov Moscow University13University Ave.Moscow 119234Russia Pontificia Universidad Catolica de Chile SantiagoChile Institute of Astronomy Russian Academy of Sciences48Pyatnitskaya Str.Moscow 109017Russia Institute for Applied Computational Science Harvard UniversityCambridgeMAUSA IAASARS National Observatory of Athens15236 PenteliGreece Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str.84/32Moscow 117997Russia

Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute （Lomonosov moscow University） in 1976-1994 and digitized with a resolution of 2400dpi, we dis- covered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type re- main not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys.

关键词： techniques photometric

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