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Integrative Zoology 2024年第1期19卷 143-155页

作者： Katharina schramm Michele SKOPEC Denise DEARING Department of Biology University of UtahSalt Lake CityUtahUSA Department of Zoology Weber State UniversityOgdenUtahUSA

Herbivory is common in mammals,yet our understanding of detoxification processes used by mammals to biotrans-form plant secondary compounds(PSCs)is *** herbivores are thought to have evolved detoxifica-tion mechanisms that rely more heavily on energetically cheap Phase I biotransformation reactions to process high levels of PSCs in their *** explored this hypothesis by comparing the urinary metabolite patterns of two spe-cialist herbivores(genus Neotoma).Neotoma stephensi is an obligate specialist on one-seeded juniper(Juniperus monosperma).Neotoma lepida is a generalist forager across its range,yet populations in the Great Basin specialize on Utah juniper(***).While both juniper species have high levels of terpenes,the terpene profiles and quantities differ between the *** from both woodrat species were fed diets of each juniper in a cross-over ***,collected over a 24-h period,was extracted and analyzed in an untargeted metabolomics approach using both GC-MS and HPLC-MS/*** obligate specialist *** excreted a unique pattern of Phase I metabolites when fed its native juniper,while *** excreted a unique pattern of Phase II metabolites when fed its native *** woodrat species utilized the Phase II metabolic pathway of glucuronidation more heavily when consuming the more chemically diverse ***,and *** utilized less glucuronida-tion than *** when consuming *** results are consistent with the hypothesis that obligate specialists may have evolved unique and efficient biotransformation mechanisms for dealing with PSCs in their diet.

关键词： dietary specialization herbivory juniper metabolomics Neotoma

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认证的可靠性:质量标志是消费者的政策工具

中国农学通报 2010年第7期26卷 55-63页

作者：朱彧邓少军樊红平 Gabriele Jahn matthias schramm Achim Spiller 农业部农产品质量安全中心北京100081 中非发展基金北京100031 The Institute of Agricultural Economics University of Goettingen

目前在食品行业中存在数量众多的认证体系,但是与认证的经济学研究却很少。认证是在市场交易中可确保商品某种隐藏质量声明真实性的有效工具。在信息不对称的情况下,诸如有机生产、动物福利、公平贸易等"过程导向"的品质特性容易产生不... 详细信息

目前在食品行业中存在数量众多的认证体系,但是与认证的经济学研究却很少。认证是在市场交易中可确保商品某种隐藏质量声明真实性的有效工具。在信息不对称的情况下,诸如有机生产、动物福利、公平贸易等"过程导向"的品质特性容易产生不正当使用标志问题。从长远来看,只有可靠的控制程序才能减少食品安全事件的发生。首先提出了一个影响认证结果和认证标志有效性的模型,然后探讨了认证市场价格战的趋势和认证制度变革的必要性,提出了减少对检查员的依赖程度、强化职责、增加公信力效应和降低认证费用等策略,最后讨论了对官方和非官方监管的政策内涵。

关键词：认证质量标志政策工具

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Dynamic convergent shock compression initiated by return current in high-intensity laser-solid interactions

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Matter and Radiation at Extremes 2024年第4期9卷 40-53页

作者： Long Yang Martin Rehwald Thomas Kluge Alejandro LasoGarcia Toma Toncian Karl Zeil Ulrich schramm Thomas E.Cowan Lingen Huang Helmholtz-Zentrum Dresden-Rossendorf 01328 DresdenGermany Technische Universitat Dresden 01062 DresdenGermany

We investigate the dynamics of convergent shock compression in solid cylindrical targets irradiated by an ultrafast relativistic laser *** particle-in-cell simulations and coupled hydrodynamic simulations reveal that the compression process is initiated by both magnetic pressure and surface ablation associated with a strong transient surface return current with density of the order of 10^(17) A/m^(2) and lifetime of 100 *** results show that the dominant compression mechanism is governed by the plasma β,i.e.,the ratio of thermal pressure to magnetic *** targets with small radius and low atomic number Z,the magnetic pressure is the dominant shock compression *** to a scaling law,as the target radius and Z increase,the surface ablation pressure becomes the main mechanism generating convergent ***,an indirect experimental indication of shocked hydrogen compression is provided by optical shadowgraphy measurements of the evolution of the plasma expansion *** results presented here provide a novel basis for the generation of extremely high pressures exceeding Gbar(100 TPa)to enable the investigation of high-pressure physics using femtosecond J-level laser pulses,offering an alternative to nanosecond kJ-laser pulse-driven and pulsed power Z-pinch compression methods.

关键词： shock convergent return

Assessment of molecular markers and marker-assisted selection for drought tolerance in barley(Hordeum vulgare L.)

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Journal of Integrative Agriculture 2024年第1期23卷 20-38页

作者： Akmaral Baidyussen Gulmira Khassanova Maral Utebayev Satyvaldy Jatayev Rystay Kushanova Sholpan Khalbayeva Aigul Amangeldiyeva Raushan Yerzhebayeva KulpashBulatova Carly schramm Peter Anderson Colin L.D.Jenkins Kathleen LSoole Yuri Shavrukov Faculty of Agronomy S.Seifullin Kazakh AgroTechnical Research UniversityAstana 010000Kazakhstan A.I.Barayev Research and Production Centre of Grain Farming Shortandy 021601Kazakhstan Kazakh Research Institute of Agriculture and Plant Growing AlmalybakAlmaty District 040909Kazakhstan College of Science and Engineering Biological SciencesFlinders UniversityAdelaideSA 5042Australia

This review updates the present status of the field of molecular markers and marker-assisted selection(MAS),using the example of drought tolerance in *** accuracy of selected quantitative trait loci(QTLs),candidate genes and suggested markers was assessed in the barley genome *** common strategies are described for molecular marker development,candidate gene identification and verification,and their possible applications in MAS to improve the grain yield and yield components in barley under drought *** strategies are based on the following five principles:(1)Molecular markers are designated as genomic‘tags’,and their‘prediction’is strongly dependent on their distance from a candidate gene on genetic or physical maps;(2)plants react differently under favourable and stressful conditions or depending on their stage of development;(3)each candidate gene must be verified by confirming its expression in the relevant conditions,e.g.,drought;(4)the molecular marker identified must be validated for MAS for tolerance to drought stress and improved grain yield;and(5)the small number of molecular markers realized for MAS in breeding,from among the many studies targeting candidate genes,can be explained by the complex nature of drought stress,and multiple stress-responsive genes in each barley genotype that are expressed differentially depending on many other factors.

关键词： barley candidate genes drought tolerance gene verification via expression grain yield marker-assisted selection(MAS) molecular markers quantitative trait loci(QTLs) strategy for MAS

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miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

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Distortions in focusing laser pulses due to spatio-temporal couplings: an analytic description

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High Power Laser Science and Engineering 2024年第3期 25-45页

作者： Klaus Steiniger Fabia Dietrich Daniel Albach Michael Bussmann Arie Irman Markus Loeser Richard Pausch Thomas Püschel Roland Sauerbrey Susanne Sch?bel Ulrich schramm Mathias Siebold Karl Zeil Alexander Debus Helmholtz-Zentrum Dresden-Rossendorf Dresden Germany CASUS-Center for Advanced Systems Understanding G?rlitz Germany Technische Universit?t Dresden Dresden Germany

In ultra-short laser pulses, small changes in dispersion properties before the final focusing mirror can lead to severe pulse distortions around the focus and therefore to very different pulse properties at the point of laser±matter interaction,yielding unexpected interaction results. The mapping between far-and near-field laser properties intricately depends on the spatial and angular dispersion properties as well as the focal geometry. For a focused Gaussian laser pulse under the influence of angular, spatial and group-delay dispersion, we derive analytical expressions for its pulse-front tilt,duration and width from a fully analytic expression for its electric field in the time±space domain obtained with scalar diffraction theory. This expression is not only valid in and near the focus but also along the entire propagation distance from the focusing mirror to the focus. Expressions relating angular, spatial and group-delay dispersion before focusing at an off-axis parabola, where they are well measurable, to the respective values in the pulse’s focus are obtained by a ray tracing approach. Together, these formulas are used to show in example setups that the pulse-front tilts of lasers with small initial dispersion can become several tens of degrees larger in the vicinity of the focus while being small directly in the focus. The formulas derived here provide the analytical foundation for observations previously made in numerical experiments. By numerically simulating Gaussian pulse propagation and measuring properties of the pulse at distances several Rayleigh lengths off the focus, we verify the analytic expressions.

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Evaluation of Ultrasound-based Surveillance for Hepatocellular Carcinoma in Patients at Risk:Results From a German Multicenter Retrospective Cohort Study

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Journal of Clinical and Translational Hepatology 2023年第3期11卷 626-637页

作者： Johannes Gillessen Philipp Reuken Peter-Marton Hunyady matthias Christian Reichert Lucian Lothschütz Fabian Finkelmeier matthias Nowka Gabriel Allo Fabian Kütting Martin Bürger Dirk Nierhoff Hans-Michael Steffen Christoph schramm University Hospital Cologne Department of Gastroenterology and HepatologyCologneGermany University Hospital Jena Department of Internal Medicine IV-GastroenterologyHepatologyInfectious DiseaseJenaGermany University Hospital Frankfurt Department of Internal Medicine 1-Gastroenterology und HepatologyPulmonology und AllergologyEndocrinologyFrankfurtGermany Department of Medicine II Saarland University Medical CenterHomburgGermany Department of Gastroenterology and Hepatology University Hospital of EssenEssenGermany

Background and Aims:Hepatocellular carcinoma(HCC)surveillance in patients at risk is strongly recommended and usually performed by ultrasound(US)semiannually with or without alfa-fetoprotein(AFP)*** pa-rameters except for surveillance intervals have not been strictly *** aimed to evaluate surveillance success and risk factors for surveillance ***:Patients with≥1 US prior to HCC diagnosis performed at four tertiary referral hospitals in Germany between 2008 and 2019 were retrospectively *** success was defined as HCC detection within Milan ***:Only 47%of 156 patients,median age 63(interquartile range:57-70)years,56%male,and 96%with cirrhosis,received recom-mended surveillance modality and *** fail-ure occurred in 29%and was significantly associated with lower median model for end-stage liver disease(MELD)score odds ratio(OR)1.154,95%confidence interval(CI):1.027-1.297,p=0.025)and HCC localization within right liver lobe(OR:6.083,95%CI:1.303-28.407,p=0.022),but not with AFP≥200μg/*** with surveillance failure had sig-nificantly more intermediate/advanced tumor stages(93%vs.6%,p<0.001),fewer curative treatment options(15%vs.75%,p<0.001)and lower survival at 1 year(54%vs.75%,p=0.041),2 years(32%vs.57%,p=0.019)and 5 years(0%vs.16%,p=0.009).Alcoholic and non-alcoholic fatty liver disease(OR:6.1,95%CI:1.7-21.3,p=0.005)and ascites(OR:3.9,95%CI:1.2-12.6,p=0.021)were in-dependently associated with severe visual limitations on ***:US-based HCC surveillance in patients at risk frequently fails and its failure is associated with unfavorable patient-related *** MELD score and HCC lo-calization within right liver lobe were significantly associated with surveillance failure.

关键词： Hepatocellular carcinoma Surveillance success Screening Ultra-sound.

Effects of propeller load fluctuations on performance and emission of a lean-burn natural gas engine at part-load conditions

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Propulsion and Power Research 2022年第2期11卷 196-208页

作者： S.Tavakoli J.schramm E.Pedersena Department of Marine Technology Norwegian University of Science and TechnologyTrondheimNorway Department of Mechanical Engineering Technical University of DenmarkLyngbyDenmark

Providing stable combustion of lean-burn natural gas engines was always a bigchallenge, particularly during a low load operation. In transient sea conditions, there is an additional concern due to irregular time-varying loads. Therefore, this study aimed at investigatingthe part-load operation of a marine spark-ignition lean-burn natural gas engine by simulatingthe entire engine. The engine’s essential components are modeled, including air manifold,intake valves, fuel system, controllers, combustion chamber, exhaust valves, exhaust manifoldand *** steady-state, the results of emission compounds from modeling have been compared tomeasured data from 25% to 100% loads. For transient conditions, for the sample time of about50 min, the fuel flow and turbocharger output are selected from the vessel logged data andcompared with the simulation results. The model has shown the great potential of predictingthe engine response throughout the steady-state and transient conditions. Simulating the engineat part-load transient condition showed that the unburned hydrocarbon formation, known asmethane slip in lean-burn gas engines, is more than the part-load steady-state. This increaseof methane slip is due to the combustion instability in lower loads and flame extinguishingin such transient conditions. The engine measured data shows a double amount of methane slipin a 25% load than the 100% load in steady-state. However, the simulation output in the transient conditions confirms an increase in methane slip over four times than equivalentsteady-state load. Moreover, the lean-burn gas engine releases less NOX in part-load operationin a steady-state due to lower in-cylinder temperature. In transient conditions, there is remarkable instability in excess air ratio. Due to this instability, there is a rich mixture in instantaneoustime steps during loads up. Therefore, it will result in an unusually high amount of NOX, andmore than two times in comparison with the equivalent

关键词： Lean-burn combustion Emission formation Methane slip NOX Part-load operation

Studies on Differential Nuclear Translocation Mechanism and Assembly of the Three Subunits of the Arabidopsis thaliana Transcription Factor NF-Y

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Molecular Plant 2012年第4期5卷 876-888页

作者： Dieter Hackenberg Yanfang Wu Andrea Voigt Robert Adams Peter schramm Bernhard GrimmI Institute of Biology/Plant Physiology Humboldt University Philippstr. 13 Building 12 10115 Berlin Germany

The eukaryotic transcription factor NF-Y consists of three subunits （A, B, and C）, which are encoded in Ara- bidopsis thaliana in multigene families consisting of 10, 13, and 13 genes, respectively. In principle, all potential combi- nations of the subunits are possible for the assembly of the heterotrimeric complex. We aimed at assessing the probability of each subunit to participate in the assembly of NF-Y. The evaluation of physical interactions among all members of the NF-Y subunit families indicate a strong requirement for NF-YB/NF-YC heterodimerization before the entire complex can be accomplished. By means of a modified yeast two-hybrid system assembly of all three subunits to a heterotrimeric complex was demonstrated. Using GFP fusion constructs, NF-YA and NF-YC localization in the nucleus was demonstrated, while NF- YB is solely imported into the nucleus as a NF-YC-associated heterodimer NF-YC. This piggyback transport of the two Arabidopsis subunits differs from the import of the NF-Y heterotrimer of heterotrophic organisms. Based on a peptide structure model of the histone-fold-motifs, disulfide bonding among intramolecular conserved cysteine residues of NF-YB, which is responsible for the redox-regulated assembly of NF-YB and NF-YC in human and Aspergillus nidulans, can be excluded for Arabidopsis NF-YB.

关键词： gene expression transcriptional control and transcription factors nuclear translocation protein-proteininteraction.

Tunable colors and conductivity by electroless growth of Cu/Cu2O particles on sol-gel modified cellulose

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Nano Research 2020年第10期13卷 2658-2664页

作者： Justus Landsiedel Waleri Root Christian schramm Alexander Menzel Steffen Witzleben Thomas Bechtold Tung Pham Research Institute for Textile Chemistry and Textile Physics University of Innsbruck6850 DornbirnAustria Department of Physical Chemistry University of Innsbruck6020 InmsbruckAustria Department of Natural Sciences Bonn Rhein sSieg University of Applied Sciences5359 RheinbachGermany

Development of colored surfaces by formation of nano-structured aggregates is a widely used strategy in nature to color lightweight structures (e.g. butterflies) without the use of dye pigments. The deposition of nanoscale particles mimics nature in it’s approach coloring surfaces. This work presents sol-gel modification of cellulose surfaces used to form a template for growth of Cu/Cu2O core–shell particles with defined size-distributions. Besides improving the adhesion of the deposited particulate material, the sol-gel matrix serves as a template for the control of particle sizes of the Cu/Cu2O structures, and as a consequence of particle size variation the surface color is tunable. As an example, red color was achieved with an average particle size of 35 nm, and shifts gradually to blue appearance when particles have grown to 80 nm on the sol-gel modified fabric. The copper concentration on representative fabrics is kept low to avoid modifying the textile characteristics and were all in the range of 150–170 mg per g of cellulose material. As a result of copper deposition on the surface of the material, the cellulose fabric also became electrically conductive. Remarkably, the electrical conductivity was found to be dependent on the average particle sizes of the deposits and thus related to the change in observed color. The generation of color by growth of nano-sized particles on sol-gel templates provides a highly promising approach to stain surfaces by physical effects without use of synthetic colorants, which opens a new strategy to improve environmental profile of coloration.

关键词： electroless copper deposition sol-gel support thin film structural coloration tunable sheet resistance LSPR