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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 sedimentologically.Three 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 basin.Eleven 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 boreholes.The 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) offshore.Deepening-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 basin.Symmetrical cycles are very rare.The 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 obvious.GR cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),reflecting alternations of facies groups of predomina

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

Temperature Difference and Stack Plate Spacing Effects on Thermodynamic Performances of Standing-Wave Thermoacoustic Engines Driven by Cryogenic Liquids and Waste Heat

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Journal of Thermal Science 2022年第5期31卷 1434-1451页

作者： GUO Lixian ZHAO Dan becker Sid Department of Mechanical Engineering College of EngineeringUniversity of CanterburyPrivate Bag 4800Christchurch8041New Zealand

The standing-wave thermoacoustic engines(TAE)are applied in practice to convert thermal power into acoustic one to generate electricity or to drive cooling devices.Although there is a number of existing numerical researches that provides a design tool for predicting standing-wave TAE performances,few existing works that compare TAE driven by cryogenic liquids and waste heat,and optimize its performance by varying the stack plate spacing.This present work is primarily concerned with the numerical investigation of the performance of TAEs driven by cryogenic liquids and waste heat.For this,three-dimensional(3-D)standing-wave TAE models are developed.Mesh-and time-independence studies are conducted first.Model validations are then performed by comparing with the numerical results available in the literature.The validated model is then applied to simulate the standing-wave TAEs driven by the cryogenic liquids and the waste heat,as the temperature gradientΔT is varied.It is found that limit cycle oscillations in both systems are successfully generated and the oscillations amplitude is increased with increasedΔT.Nonlinearity is identified with acoustic streaming and the flow reversal occurring through the stack.Comparison studied are then conducted between the cryogenic liquid-driven TAE and that driven by waste heat in the presence of the same temperature gradientΔT.It is shown that the limit cycle frequency of the cryogenic liquid system is 4.72%smaller and the critical temperatureΔT_(cri)=131 K is lower than that of the waste heat system(ΔT_(cri)=187 K).Furthermore,the acoustic power is increased by 31%and the energy conversion efficiency is found to increase by 0.42%.Finally,optimization studies on the stack plate spacing are conducted in TAE system driven by cryogenic liquids.It is found that the limit cycle oscillation frequency is increased with the decreased ratio between the stack plate spacing and the heat penetration depth.When the ratio is set to between 2 and 3,the overall performance of the cryogenic liqui

关键词： thermoacoustic engine standing-wave cryogenic thermodynamics acoustical energy plate spacing heat transfer acoustic streaming

Ultrasonically Assisted Cutting of Histological Sections for Reducing the Environmental and Financial Impact of Microtomy

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 200-206页

作者： Dong Wang Daniel De becker Anish Roy Wolfson School of Mechanical and Manufacturing Engineering Loughborough UniversityLoughborough LE113TUUK Department of Engineering College of EngineeringMathematics and Physical SciencesUniversity of ExeterExeter EX44QFUK

Modern-day microtomy requires high precision equipment to thinly section biological tissues.The sectioned tissue must be of good quality not showing cutting tracks or so-called artefacts.The quality of these sections is dependent on the blade wear,which is related to the hardness of the tissue sample,cutting angle and cutting speed.A test rig has been designed and manufactured to allow these parameters to be controlled.This has allowed for the blade wear to be analysed and quantified,and this has been completed for both ultrasonically assisted and conventional cutting.The obtained results showed a 25.2%decrease in average blade roughness after 38 cuts when using the ultrasonically assisted cutting regime.The data also showed no adverse effect on the quality of the slides produced when using this cutting methodology.Finally,the cutting force measured for both cutting regimes showed that ultrasonically assisted cutting required less force compared to conventional cutting.With the reduction of surface roughness and force,it is possible to state that ultrasonically assisted cutting reduces the wear of the blade,thereby increasing the life of the blades.An increase of just 10%in blade life would yield a cost saving of approximately 25%thereby reducing the environmental and financial impact of microtomy.

关键词： Microtome Ultrasonically assisted cutting Blade wear

Data-driven prediction of plate velocities and plate deformation of explosive reactive armor

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Defence Technology（防务技术） 2022年第12期18卷 2141-2149页

作者： Marvin becker Andreas Klavzar Thomas Wolf Melissa Renck Institute of Saint-Louis 5 Rue du Général Cassagnou68330Saint LouisCedexFrance Ecole Centrale de Lille CitéScientifique59651Villeneuve d'AscqCedexFrance

Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets.Considering mobility,the aim is to design a protection system with a minimal amount of required mass.The efficiency of an ERA is sensitive to the impact position and the timing of the detonation.Therefore,different designs have to be tested for several impact scenarios to identify the best design.Since analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed here.The ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with experiments.The ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in real-time.In a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given threat.Then,a measure for the effectiveness of an ERA can be calculated.Finally,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.

关键词： Artificial neural network Explosive reactive armor Finite element simulation Particle simulation Flash X-ray

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 variation.Joint calling is routinely used to combine identified variants across multiple related samples.However,the improvement of variants identification using the mutual support information from mul-tiple samples remains quite limited for population-scale genotyping.Results 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’data.The 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 variants.The 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 identification of genetic variants.This strategy did not

关键词： Computational framework Genetic variants Multiple samples Sheep

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 cost.Conventional approaches,including selfing or backcrossing,cannot provide this.Haploid 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

利用微流控技术应对COVID-19和其他肺部疾病的全球挑战

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Engineering 2023年第5期24卷 17-20,I0001页

作者： Yuliang Xie Ryan becker Michael Scott Kayla Bean Tony Jun Huang Roy J.Carver Department of Biomedical Engineering College of EngineeringUniversity of IowaIowa CityIA 52242USA Department of Biomedical Engineering Pratt School of EngineeringDuke UniversityDurhamNC 27710USA Department of Mechanical Engineering and Materials Science Pratt School of EngineeringDuke UniversityDurhamNC 27710USA

1. Introduction Pulmonary diseases present one of the most severe threats to human society. Since late 2019, the coronavirus disease 2019(COVID-19) pandemic has significantly impacted the lifestyle, culture, and politics of almost everyone in the world. COVID-19 causes severe pulmonary dysfunction, which is a major cause of mortality for those affected [1].

关键词：微流控技术肺部疾病全球挑战

Involvement of CYP347W1 in neurotoxin 3-nitropropionic acid-based chemical defense in mustard leaf beetle Phaedon cochleariae

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Insect Science 2022年第2期29卷 453-466页

作者： Nanxia Fu Tobias becker Wolfgang Brandt Maritta Kunert Antje Burse Wilhelm Boland Department of Bioorganic Chemistry Max Planck Institute for Chemical EcologyJenaGermany Key Laboratory of Tea Biology and Resource Utilization Tea Research InstituteChinese Academy of Agricultural SciencesHangzhouChina Department of Bioorganic Chemistry Leibniz Institute of Plant BiochemistryHalle(Saale)Germany Department of Natural Product Biosynthesis Max Planck Institute for Chemical EcologyJenaGermany Department of Medical Technology and Biotechnology Ernst Abbe Hochschule JenaJenaGermany

Chrysomelina beetlesstore 3-nitropropionic acid in form of a pretoxin,isoxazolin-5-one glucoside-conjugated ester,to protect themselves against predators.Here we identified a cytochrome P450 monooxygenase,CYP347W1,to be involved in the production of the 3-nitropropionic acid moiety of the isoxazolin-5-one glucoside ester.Knocking down CYP347W1 led to a significant depletion in the concentration of the isoxazolin-5-one glucoside ester and an increase in the concentration of the isoxazolin-5-one glucoside in the larval hemolymph.Enzyme assays with the heterologously expressed CYP347W1 showed freeβ-alanine was not the direct substrate.Homology modeling indicated thatβ-alanine-CoA ester can fit into CYP347W1’s active site.Furthermore,we proved that Phaedon cochleariae eggs are not able to de novo synthesize 3-NPA,although both isoxazolin-5-one glucoside and its 3-NPA-conjugated ester are present in the eggs.These results provide direct evidence for the involvement of CYP347W1 in the biosynthesis of a P.cochleariae chemical defense compound.

关键词： chemical defense isoxazolin-5-one glucoside isoxazolin-5-one glucoside ester leaf beetles P450 3-nitropropionic acid(3-NPA)

Labor Market Performance and Manufacturing Sector Contribution of Immigrants in Germany ——A Geographical Comparison

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Labor Market Performance and Manufacturing Sector Contributi...

作者： becker IRINA 山东大学

学位级别：硕士

Immigration and refugee integration are some of the great global challenges of the present.Based on an OECD ranking,Germany is the second most popular migration destination after the US（OECD Migration Outlook,2018）.In 2015,it adopted an open border policy and took in 890,000 refugees,where over 70,000 formally applied for political asylum.What started as a humanitarian act could result in an economic benefit for Germany:There is a growing demand for skilled workers on the one hand and Germany’s ageing population as well as shrinking birth rates on the other.Once successfully integrated,immigrants could advert the predicted demographic development.In order to achieve that,the importance of developing a deep understanding of the labor and manufacturing sector performance of refugees and immigrants is a necessity.Therefore,the paper aims to investigate the nexus between an increase in the refugee flock,the labor market and manufacturing sector performance based on geographical regions within Germany.As such,the paper adopted both,time series and panel data using different econometric models in order to estimate the impact of immigrants and especially refugees.To avoid working with inconsistent and unreliable data,the paper ran different diagnostic tests,revealing that the variables and models are consistent.Differently,the regression estimates revealed that an increase in refugees is associated with a fall in both,the unemployment rate and the wage rate.Moreover,the adopted IV model showed that the impact is based on gender with males negatively contributing to the unemployment rate,and females positively contributing to the unemployment rate.Under the wage rate IV model,the estimates indicate that immigrants’ origin significantly and differently affect the wage rate.Focusing on manufacturing performance:the paper concluded by stating that city immigrants contribute more to the return on equity of manufacturing companies than immigrants in municipal regions.The paper also revealed that the performance of the labor m

关键词： Manufacturing Immigrants Labor Market Performance Germany