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Skeletal microstructures of cheilostome bryozoans(phylum Bryozoa,class Gymnolaemata):crystallography and secretion patterns

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Marine Life Science & Technology 2024年第3期6卷 405-424页

作者： christian Grenier Erika Griesshaber Wolfgang Schmahl Björn Berning Antonio G.Checa Departamento de Estratigrafía y Paleontología Universidad de Granada18071 GranadaSpain Instituto Andaluz de Ciencias de La Tierra CSIC-Universidad de Granada18100 ArmillaSpain Department of Earth and Environmental Sciences Ludwig-Maximilians Universität80333 MunichGermany Institute for Geology University of Hamburg20146 HamburgGermany

Gymnolaemata bryozoans produce CaCO3 skeletons of either calcite,aragonite,or *** extensive research,their crystallography and biomineralization patterns remain *** present a detailed study of the microstructures,min-eralogy,and crystallography of eight extant cheilostome species using scanning electron microscopy,electron backscatter diffraction,atomic force microscopy,and micro-computed *** distinguished five basic microstructures,three calcitic(tabular,irregularly platy,and granular),and two aragonitic(granular-platy and fibrous).The calcitic microstruc-tures consist of crystal aggregates that transition from tabular or irregularly platy to granular *** aragonite consists of fibers arranged into *** all cases,the crystallographic textures are axial,and stronger in aragonite than in calcite,with the c-axis as the fiber *** reconstruct the biomineralization sequence in the different species by considering the distribution and morphology of the growth fronts of crystals and the location of the secretory *** bimineralic species,calcite formation always predates aragonite *** interior compound walls,growth proceeds from the cuticle toward the zooecium *** conclude that,with the exception of tabular calcite,biomineralization is remote and occurs within a relatively wide extrapallial space,which is consistent with the inorganic-like appearance of the *** biomineralization mode is rare among invertebrates.

关键词： Biomineralization Bryozoan Skeleton Calcite Aragonite Electron backscatter diffraction

Univariate and multivariate analysis of risk factors for severe clostridium difficile-associated diarrhoea: Importance of co-morbidity and serum C-reactive protein

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World Journal of Gastroenterology 2008年第27期14卷 4338-4341页

作者： christian Hardt Thomas Berns Wolfgang Treder Franz ludwig Dumoulin Department of Medicine Gemeinschaftskrankenhaus Bonn Department of Surgery St.-Agnes-Hospital Bocholt Münster Center for Laboratory Diagnostics

AIM: To investigate risk factors for severe clostridium difficile associated diarrhoea (CDAD) in hospitalised patients. METHODS: We analysed risk factors for severe CDAD (associated with systemic signs of hypovolemia) in 124 hospitalised patients by retrospective chart review. RESULTS: Severe CDAD was present in 27 patients (22%). Statistical analysis showed a significant association with a higher 30-d mortality (33% vs 4%, P < 0.001) and a higher proportion of longer hospital stay exceeding 14 d (74% vs 52%, P = 0.048). Charlson co-morbidity score (OR 1.29 for 1 point increment, P < 0.05) and serum C-reactive protein at diagnosis (OR 1.15 for 10 mg/L increment, P < 0.001) were independent predictors of severe CDAD. CONCLUSION: Patients with a severe level of co- morbidity and high serum C-reactive protein levels at the time of diagnosis should receive particular attention.

关键词： Clostridium difficile Nosocomial diarrhoea Co-morbidity C-reactive protein 30-day mortality

Inhibition of DNA-Topoisomerase I by Acylated Triterpene Saponins from Pittosporum angustifolium Lodd.

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Natural Products and Bioprospecting 2016年第2期6卷 141-147页

作者： christian Backer Malgorzata N.Drwal Robert Preissner ulrike Lindequist Department of Pharmaceutical Biology Institute of PharmacyErnst Moritz Arndt University GreifswaldFriedrich-Ludwig-Jahn-Straße 1717489 GreifswaldGermany Structural Bioinformatics Group Institute for PhysiologyCharite´-University Medicine BerlinLindenberger Weg 8013125 BerlinGermany

Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium *** to the isolation and structural elucidation of polyphenols and triterpene *** for cytotoxicity of isolated saponins revealed that the predominant structural feature for a cytotoxic activity are acyl substituents at the oleanane aglycon *** present work reports the results of a screening of 10 selected acylated saponins for their potential to inhibit the human DNA-topoisomerase I,giving rise to IC50 values in a range of 2.8-46.5 *** clarify the mode of observed cytotoxic action and,moreover,to distinguish from a pure surfactant effect which is commonly accompanied with saponins,these results indicate an involvement of the topoisomerase I and its role as a possible target structure for a cytotoxic *** addition,computational predictions of the fitting of saponins to the topoisomerase I-DNA complex,indicate a similar binding mode to that of clinically used topoisomerase I *** Abstract Ten acylated triterpene saponins from Pittosporum angustifolium were investigated for their potential to inhibit the human DNA-topoisomerase I and computational predictions of the fitting of saponins to the topoisomerase I-DNA complex were carried out.

关键词： Pittosporum angustifolium Acylated triterpene saponins Cytotoxicity Topoisomerase I Docking

Machine Learning to Detect Alzheimer’s Disease from Circulating Non-coding RNAs

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Genomics, Proteomics & Bioinformatics 2019年第4期17卷 430-440页

作者： Nicole ludwig Tobias Fehlmann Fabian Kern Manfred Gogol Walter Maetzler Stephanie Deutscher Simone Gurlit Claudia Schulte Anna-Katharina von Thaler christian Deuschle Florian Metzger Daniela Berg ulrike Suenkel Verena Keller Christina Backes Hans-Peter Lenhof Eckart Meese Andreas Keller Department of Human Genetics Saarland University66421 Homburg/SaarGermany Chair for Clinical Bioinformatics Saarland University66123 Saarbru¨ckenGermany Institut fur Gerontologie Universitat Heidelberg69047 HeidelbergGermany Department of Neurology Christian-Albrechts-University of Kiel24118 KielGermany Center for Neurology and Hertie Institute for Clinical Brain Research Department of NeurodegenerationUniversity of Tuebingen72074 TuebingenGermany German Center for Neurodegenerative Diseases(DZNE) 72076 TuebingenGermany Department of Anesthesiology and Intensive Care St.Franziskus Hospital Muenster48145 MuensterGermany Department of Psychiatry and Psychotherapy University Hospital Tuebingen72016 TuebingenGermany Department of Medicine II Saarland University Medical Center66421 Homburg/SaarGermany Center for Bioinformatics Saarland Informatics Campus66123 SaarbruckenGermany

Blood-borne small non-coding(snc RNAs)are among the prominent candidates for blood-based diagnostic ***,high-throughput approaches are applied to discover biomarker *** have to be validated in larger cohorts and evaluated by adequate statistical learning ***,we published high-throughput sequencing based microRNA(miRNA)signatures in Alzheimer’s disease(AD)patients in the United States(US)and ***,we determined abundance levels of 21 known circulating miRNAs in 465 individuals encompassing AD patients and controls by *** computed models to assess the relation between miRNA expression and phenotypes,gender,age,or disease severity(Mini-Mental State Examination;MMSE).Of the 21 miRNAs,expression levels of 20 miRNAs were consistently de-regulated in the US and German cohorts.18 miRNAs were significantly correlated with neurodegeneration(Benjamini-Hochberg adjusted P<0.05)with highest significance for miR-532-5 p(BenjaminiHochberg adjusted P=4.8×10^-30).Machine learning models reached an area under the curve(AUC)value of 87.6%in differentiating AD patients from ***,ten miRNAs were significantly correlated with MMSE,in particular miR-26a/26b-5p(adjusted P=0.0002).Interestingly,the miRNAs with lower abundance in AD were enriched in monocytes and T-helper cells,while those up-regulated in AD were enriched in serum,exosomes,cytotoxic t-cells,and *** study represents the next important step in translational research for a miRNA-based AD test.

关键词： miRNAs Neurodegeneration Alzheimer’s disease Biomarker Non-coding RNAs Gene regulation

Norton-Hoff model for deformation of growing solid shell of thin slab casting in funnel-shape mold

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Journal of Iron and Steel Research International 2022年第1期29卷 88-102页

作者： Alexander Vakhrushev Abdellah Kharicha Menghuai Wu Andreas ludwig Gerald Nitzl Yong Tang Gernot Hackl Josef Watzinger christian M.G.Rodrigues christian-Doppler Laboratory for Metallurgical Applications of Magnetohydrodynamics Montanuniversitat Leoben8700 LeobenAustria Primetals Technologies 4031 LinzAustria Chair of Simulation and Modeling of Metallurgical Processes Department of MetallurgyMontanuniversit?t Leoben8700 LeobenAustria RHI Magnesita GmbH 1120 ViennaAustria RHI Magnesita GmbH 8700 LeobenAustria

A funnel-type mold is commonly used to provide necessary clearance for the submerged entry nozzle in the thin slab casting(TSC).The partially solidified shell is subjected to the mechanical deformations,which can lead to the defects formation and,as a results,to a ***,the results of the flow simulation,performed by the finite volume method(FVM),are fed to the external package for the finite element analysis of stress and strain.A coupled model was assembled using“creeping solid”approach by blending the Norton-Hoff viscoplastic stress for the solidifying shell with the Newtonian viscous stress of the liquid *** FVM was used to combine both liquid and solid stress models within a single *** iterative procedure based on the improved both side diffusion method was introduced to treat the nonlinear relation between the viscoplastic stress and the strain *** modeled shell thickness was verified by previously published breakout measurements and the simulation *** distribution,obtained during the TSC simulation,dominantly corresponds to the viscoplastic *** numerical approach is robust and has direct industrial application.

关键词： Solid shell Viscoplastic stress Solidification Norton-Hoff model Thin slab Continuous casting Improved both side diffusion method OpenFOAM

气候对伊比利亚半岛尼安德特人向现代人人种转变的影响

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Science Bulletin 2023年第11期68卷 1176-1186,M0004页

作者： Konstantin Klein Gerd-christian Weniger Patrick ludwig christian Stepanek 张旭 christian Wegener 邵亚平 Institute for Geophysics and Meteorology University of CologneCologne 50923Germany Institute of Prehistory University of CologneCologne 50923Germany Institute of Meteorology and Climate Research Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Paleoclimate Dynamics Alfred Wegener InstituteHelmholtz Centre for Polar and Marine ResearchBremerhaven 27570Germany Alpine Paleoecology and Human Adaption Group State Key Laboratory of Tibetan Plateau Earth SystemChinese Academy of SciencesBeijing 100101China

伊比利亚半岛对从尼安德特人到现代人的人种转变有着特殊的意义.从东欧向西迁徙的现代人较晚才抵达伊比利亚,因此两个种群之间在这里发生任何可能接触的时间要晚于其他地方.伊比利亚半岛的人种转变发生在海洋同位素第3阶段的早期(约6万... 详细信息

伊比利亚半岛对从尼安德特人到现代人的人种转变有着特殊的意义.从东欧向西迁徙的现代人较晚才抵达伊比利亚,因此两个种群之间在这里发生任何可能接触的时间要晚于其他地方.伊比利亚半岛的人种转变发生在海洋同位素第3阶段的早期(约6万到2.7万年前),其间反复强烈的气候变化影响了种群稳定性.本文研究了气候变化和人类相互作用如何影响种群的过渡.结合气候数据与考古遗址数据重建了GI11-10(格陵兰间冰期)和GS10-9/HE4(格陵兰冰期)时期尼安德特人和现代人的生存潜力或生存概率.结果发现,由于气候变化,在GS10-9/HE4期间,伊比利亚半岛的大部分地区已不适合尼安德特人的生存.尼安德特人的定居区收缩为较为孤立的沿海热点.这可能使得尼安德特人的种群结构变得更不稳定,从而引发人口的最终崩溃.现代人大约在GI10期间抵达了伊比利亚,但仅限于半岛最北部地带的局部地区.GS10-9/HE4的寒冷气候阻止了他们的进一步扩张,甚至导致了他们定居区域的缩小.气候变化与人口迁徙使得尼安德特人和现代人两个种群的人口分散在半岛的不同区域.因此,尼安德特人和现代人在广泛的地区共存的可能性不大,而现代人对尼安德特人的最后消亡的影响也有限.

关键词：尼安德特人伊比利亚半岛数据重建气候变化影响考古遗址人口迁徙生存概率人口分散

survivin、XIAP在骨髓增生异常综合征患者及其细胞株MUTZ-1中的表达及意义

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中华血液学杂志 2004年第1期25卷 26-30页

作者：蔡真包悍英 Wolf-Dieter ludwig christian Wuchter 浙江大学医学院附属第一医院杭州310003 Institute of Hematology Oncology and Tumor ImmunologyRobert Roessle ClinicHumboldt University

目的　研究骨髓增生异常综合征 (MDS)患者及MDS RAEB细胞株MUTZ 1凋亡蛋白抑制因子survivin、XIAP的表达和高三尖杉酯碱 (HHT)诱导MUTZ 1细胞凋亡的作用机制。方法　以 4 7例初发MDS患者及 15名异基因骨髓移植志愿供者为研究对象 ,应用R... 详细信息

目的　研究骨髓增生异常综合征 (MDS)患者及MDS RAEB细胞株MUTZ 1凋亡蛋白抑制因子survivin、XIAP的表达和高三尖杉酯碱 (HHT)诱导MUTZ 1细胞凋亡的作用机制。方法　以 4 7例初发MDS患者及 15名异基因骨髓移植志愿供者为研究对象 ,应用RT PCR方法检测survivin、XIAPmRNA表达 ;采用流式细胞术分析MDS RAEB细胞系MUTZ 1细胞凋亡和细胞周期变化 ,RT PCR技术检测survivin、XIAP在MUTZ 1中的表达 ;研究survivin反义寡脱氧核苷酸 (AS ODN)和HHT对细胞增殖、凋亡的影响。结果　MDS患者survivinmRNA总阳性率高于正常对照组 (分别为 38.3%和 0 ,P <0 .0 1) ,高危组 (RAEB、RAEB t、CMML)阳性率高于低危组 (分别为 5 3.6 %和 16 .7% ,P <0 .0 5 )。MDS患者及正常对照均表达XIAP ,但表达水平不同 ,其中低危组XIAPmRNA(0 .74± 0 .2 4 )低于正常对照组 (1.0 1±0 2 8) (P <0 .0 5 ) ,高危组XIAPmRNA表达 (1.5 5± 0 .34)高于低危组及正常对照组 (P值均 <0 .0 1)。HHT能诱导MUTZ 1细胞凋亡 ,凋亡率与作用浓度和时间呈正相关 ,细胞被阻滞在G2 期 ;HHT作用MUTZ 1细胞 6h后细胞内survivin表达下调 ,而XIAP表达无明显变化。survivinAS ODN能明显抑制细胞增殖及诱导细胞凋亡 ,并提高MUTZ 1细胞对HHT的敏感性。结论　凋亡?

关键词：骨髓增生异常综合征 MUTZ-1细胞株细胞凋亡 survivin基因 XIAP基因三尖杉酯碱细胞培养

F）remature melt solidification during mold filling and its nfluence on the as-cast structure

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Frontiers of Mechanical Engineering 2018年第1期13卷 53-65页

作者： M. WU M. AHMADEIN A. ludwig Chair for Simulation and Modeling of Metallurgical Processes University of Leoben Leoben A-8700 Austria christian-Doppler Laboratory for Advanced Process Simulation ofSolidification and Melting Department of Metallurgy University ofLeoben Leoben A-8700 Austria Production Engineering and Mechanical Design Department Faculty ofEngineering Tanta University Tanta 31111 Egypt

Premature melt solidification is the solidifica- tion of a melt during mold filling. In this study, a numerical model is used to analyze the influence of the pouring process on the premature solidification. The numerical model considers three phases, namely, air, melt, and equiaxed crystals. The crystals are assumed to have originated from the heterogeneous nucleation in the undercooled melt resulting from the first contact of the melt with the cold mold during pouring. The transport of the crystals by the melt flow, in accordance with the so- called ＂big bang＂ theory, is considered. The crystals are assumed globular in morphology and capable of growing according to the local constitutional undercooling. These crystals can also be remelted by mixing with the super- heated melt. As the modeling results, the evolutionary trends of the number density of the crystals and the volume fraction of the solid crystals in the melt during pouring are presented. The calculated number density of the crystals and the volume fraction of the solid crystals in the melt at the end of pouring are used as the initial conditions for the subsequent solidification simulation of the evolution of the as-cast structure. A five-phase volume-average model for mixed columnar-equiaxed solidification is used for the solidification simulation. An improved agreement between the simulation and experimental results is achieved by considering the effect of premature melt solidification during mold filling. Finally, the influences of pouring parameters, namely, pouring temperature, initial mold temperature, and pouring rate, on the premature melt solidification are discussed.

关键词： premature solidification mold filling as-caststructure modeling

Systematic Cross-biospecimen Evaluation of DNA Extraction Kits for Long-and Short-read Multi-metagenomic Sequencing Studies

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Genomics, Proteomics & Bioinformatics 2022年第2期20卷 405-417页

作者： Jacqueline Rehner Georges Pierre Schmartz Laura Groeger Jan Dastbaz Nicole ludwig Matthias Hannig Stefan Rupf Berthold Seitz Elias Flockerzi Tim Berger Matthias christian Reichert Marcin Krawczyk Eckart Meese christian Herr Robert Bals Soren L.Becker Andreas Keller Rolf Muller The IMAGINE Consortium Institute of Medical Microbiology and Hygiene Saarland UniversityD-66421 HomburgGermany Clinical Bioinformatics Saarland UniversityD-66123 SaarbruckenGermany Department of Human Genetics Saarland UniversityD-66421 HomburgGermany Helmholtz Institute for Pharmaceutical Research Saarland D-66123 SaarbruckenGermany Clinic of Operative Dentistry Periodontology and Preventive DentistrySaarland UniversityD-66421 HomburgGermany Department of Ophthalmology Saarland University Medical CenterD-66421 HomburgGermany Department of Medicine Ⅱ Saarland University Medical CenterD-66421 HomburgGermany Department of Internal Medicine V–Pulmonology AllergologyIntensive Care MedicineSaarland UniversityD-66421 HomburgGermany

High-quality DNA extraction is a crucial step in metagenomic *** by different isolation kits impairs the comparison across datasets.A trending topic is,however,the analysis of multiple metagenomes from the same patients to draw a holistic picture of microbiota associated with *** thus collected bile,stool,saliva,plaque,sputum,and conjunctival swab samples and performed DNA extraction with three commercial *** each combination of the specimen type and DNA extraction kit,20-gigabase(Gb)metagenomic data were generated using short-read *** profiles of the specimen types showed close proximity to each other,we observed notable differences in the alpha diversity and composition of the microbiota depending on the DNA extraction *** kit outperformed all selected kits on every *** reached consistently good results using the Qiagen QiAamp DNA Microbiome *** on the specimen,our data indicate that over 10 Gb of sequencing data are required to achieve sufficient resolution,but DNA-based identification is superior to identification by mass ***,longread nanopore sequencing confirmed the results(correlation coefficient>0.98).Our results thus suggest using a strategy with only one kit for studies aiming for a direct comparison of multiple microbiotas from the same patients.

关键词： Whole-genome analysis Comparative genomics Short-read sequencing Long-read sequencing DNA extraction Metagenomics