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Outlook on the gut microbiota

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Gastroenterology Report 2022年第1期10卷 1-2页

作者： bjoern O.Schroeder Department of Molecular Biology UmeaUniversityUmeaSweden Laboratory for Molecular Infection Medicine Sweden(MIMS) UmeaUniversityUmeaSweden

Despite being a rather young research field that only emerged in the last two decades,it has become clear that the gut microbiota is an essential part of our body that strongly influences the processes that regulate our health and wellbeing.In this Special Issue of Gastroenterology Report,we have compiled a collection of articles which discuss that microbial signals deriving from our internal bioreactor are by no means restricted to the gut environment,and why it is thus reasonable to consider the gut microbial community as an additional organ to our body.

关键词： Outlook spite restricted

Morphological residual convolutional neural network(M-RCNN)for intelligent recognition of wear particles from artificial joints

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Friction 2022年第4期10卷 560-572页

作者： Xiaobin HU Jian SONG Zhenhua LIAO Yuhong LIU Jian GAO bjoern MENZE Weiqiang LIU Department of Computer Science Technical University of MunichGarching 85748Germany School of Biomedical Engineering Sun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Biomedical Materials and Implant Devices Research Institute of Tsinghua University in ShenzhenShenzhen 518057China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Mckelvey School of Engineering Washington University in Saint LouisSt.LouisMO 63130USA

Finding the correct category of wear particles is important to understand the tribological behavior.However,manual identification is tedious and time-consuming.We here propose an automatic morphological residual convolutional neural network(M-RCNN),exploiting the residual knowledge and morphological priors between various particle types.We also employ data augmentation to prevent performance deterioration caused by the extremely imbalanced problem of class distribution.Experimental results indicate that our morphological priors are distinguishable and beneficial to largely boosting overall performance.M-RCNN demonstrates a much higher accuracy(0.940)than the deep residual network(0.845)and support vector machine(0.821).This work provides an effective solution for automatically identifying wear particles and can be a powerful tool to further analyze the failure mechanisms of artificial joints.

关键词： wear particles classifier morphological priors data augmentation deep residual network

Influence of test procedure on dielectric breakdown strength of alumina

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Journal of Advanced Ceramics 2019年第2期8卷 247-255页

作者： bjoern MIELLER Bundesanstalt fuer Materialforschung und-pruefung (BAM) Division Advanced Technical Ceramics

Dielectric strength testing of ceramics can be performed with various setups and parameters. Comparisons of results from different sources are often not meaningful, because the results are strongly dependent on the actual testing procedure. The aim of this study is to quantify the influence of voltage ramp rate, electrode size, electrode conditioning, and sample thickness on the measured AC dielectric strength of a commercial alumina. Mean values, Weibull moduli, and failure probabilities determined in standardized short time tests are evaluated and related to withstand voltage tests. Dielectric strength values in the range from 21.6 to 33.2 kV·mm–1 were obtained for the same material using different testing procedures. Short time tests resulted in small standard deviations(< 2 kV·mm–1) and high Weibull moduli around 30, while withstand tests at voltage levels with low and virtual zero failure probability in short time tests resulted in large scatter of withstand time and Weibull moduli < 1. The strong decrease in Weibull moduli is attributed to progressive damage from partial discharge and depolarization during AC testing. These findings emphasize the necessity of a thorough documentation of testing procedure and highlight the importance of withstand voltage tests for a comprehensive material characterization.

关键词： dielectric strength dielectric breakdown withstand voltage test high AC voltage testing

Engineering Nannochloropsis oceanica for the production of diterpenoid compounds

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mLife 2023年第4期2卷 428-437页

作者： Zhi-Yan Du Wajid W.Bhat Eric Poliner Sean Johnson Conor Bertucci Eva Farre bjoern Hamberger Department of Molecular Biosciences and Bioengineering University of Hawaii at ManoaHonoluluHawaiiUSA Department of Biochemistry and Molecular Biology Michigan State UniversityEast LansingMichiganUSA Department of Plant Biology Michigan State UniversityEast LansingMichiganUSA New England Biolabs Inc. 240 County Roadlpswich01938 MAUSA

Photosynthetic microalgae like Nannochloropsis hold enormous potential as sustainable,light-driven biofactories for the production of high-value natural products such as terpenoids.Nannochloropsis oceanica is distinguished as a particularly robust host with extensive genomic and transgenic resources available.Its capacity to grow in wastewater,brackish,and sea waters,coupled with advances in microalgal metabolic engineering,genome editing,and synthetic biology,provides an excellent opportunity.In the present work,we demonstrate how N.oceanica can be engineered to produce the diterpene casbene—an important intermediate in the biosynthesis of pharmacologically relevant macrocyclic diterpenoids.Casbene accumulated after stably expressing and targeting the casbene synthase from Daphne genkwa(DgTPS1)to the algal chloroplast.The engineered strains yielded production titers of up to 0.12 mg g^(−1) total dry cell weight(DCW)casbene.Heterologous overexpression and chloroplast targeting of two upstream rate-limiting enzymes in the 2-C-methyl-d-erythritol 4-phosphate pathway,Coleus forskohlii 1-deoxy-d-xylulose-5-phosphate synthase and geranylgeranyl diphosphate synthase genes,further enhanced the yield of casbene to a titer up to 1.80 mg g^(−1) DCW.The results presented here form a basis for further development and production of complex plant diterpenoids in microalgae.

关键词： casbene microalgae plastid targeting synthetic biology terpene synthase

A self-made, low-cost infrared system for evaluating the sciatic functional index in mice

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Neural Regeneration Research 2016年第5期11卷 829-834页

作者： Lukas Fricker Vincenzo Penna Florian Lampert G.bjoern Stark Christian Witzel Georgios Koulaxouzidis Department of Plastic and Hand Surgery University of Freiburg Medical Center Plastic and Reconstructive Surgery Charité – Universit?tsmedizin Berlin

The sciatic functional index（SFI） is a popular parameter for peripheral nerve evaluation that relies on footprints obtained with ink and paper. Drawbacks include smearing artefacts and a lack of dynamic information during measurement. Modern applications use digitized systems that can deliver results with less analytical effort and fewer mice. However, the systems are expensive（€40,000）. This study aimed to evaluate the applicability and precision of a self-made, low-cost infrared system for evaluating SFI in mice. Mice were subjected to unilateral sciatic nerve crush injury（crush group; n = 7） and sham operation（sham group; n = 4）. They were evaluated on the day before surgery, the 2nd, 4th and 6th days after injury, and then every day up to the 23rd day after injury. We compared two SFI evaluation methods, i.e., conventional inkand-paper SFI（C-SFI） and our infrared system（I-SFI）. Our apparatus visualized footprints with totally internally reflected infrared light（950 nm） and a camera that can only detect this wavelength. Additionally we performed an analysis with the ladder beam walking test（LBWT） as a reference test. I-SFI assessment reduced the standard deviation by about 33 percent, from 11.6 to 7.8, and cut the variance around the baseline to 21 percent. The system thus requires fewer measurement repetitions and fewer animals, and cuts the cost of keeping the animals. The apparatus cost €321 to build. Our results show that the process of obtaining the SFI can be made more precise via digitization with a self-made, low-cost infrared system.

关键词： nerve regeneration sciatic nerve crush frustrated total internal reflection infrared ladder beamwalking test error rate mouse peripheral nerve injury neural regeneration

肠道黏液层如何应对肠道菌群:抗击还是哺育?

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Gastroenterology Report 2019年第1期7卷 3-12,I0001页

作者： bjoern O.Schroeder Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical MedicineInstitute of MedicineBruna Stra°ket 16University of GothenburgSE 41345 GothenburgSweden

肠道居住着大量微生物,即所谓的肠道菌群。这些微生物与宿主是一种共生关系,可协助宿主降解复杂的碳水复合物。尽管肠道菌群通常被认为是有益的,但大量存在的微生物细胞对宿主来说也是一种永久性的威胁。因此,肠道上皮覆以一层致密的黏... 详细信息

肠道居住着大量微生物,即所谓的肠道菌群。这些微生物与宿主是一种共生关系,可协助宿主降解复杂的碳水复合物。尽管肠道菌群通常被认为是有益的,但大量存在的微生物细胞对宿主来说也是一种永久性的威胁。因此,肠道上皮覆以一层致密的黏液层,以防止肠道菌群进入下层组织。肠道黏液是一种有着宿主特异性多糖结构的糖蛋白网络。黏液层长久以来一直被认为是一种被动的、宿主设计的屏障,但最新研究显示,黏液层的成熟和功能在很大程度上受肠道菌群的影响。反过来,一些黏膜相关的细菌也能特异性地与黏蛋白中的多糖链结合或降解之,将其作为营养来源。由于肠道黏液层处于宿主与微生物相互作用的关键界面,该层结构的损坏会导致肠道菌群的侵入并最终引起炎症和感染。于是我们在结肠炎大鼠模型和结肠炎患者中,可以观察到黏液层的功能丧失。而且,现代社会中低纤维的西方饮食已被证实会引起细菌介导的肠道黏液层结构损害。在此,本文对健康状态和疾病状态下肠道菌群与肠道黏液层之间的相互作用进行阐述。了解宿主与微生物之间相互作用的具体分子机制,或可研发出针对黏液层功能失调相关疾病(如溃疡性结肠炎)新的治疗手段。

关键词： Dietary fiber gut microbiota host-microbe interaction inflammatory bowel disease mucus mucin mucosal barrier metabolic disease probiotics ulcerative colitis

Surface modification of biomedical Mg-Ca and Mg-Zn-Ca alloys using selective laser melting: Corrosion behaviour, microhardness and biocompatibility

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Journal of Magnesium and Alloys 2021年第6期9卷 2155-2168页

作者： Xiyu Yao Jincheng Tang Yinghao Zhou Andrej Atrens Matthew S.Dargusch bjoern Wiese Thomas Ebel Ming Yan School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China The University of Queensland School of Mechanical and Mining EngineeringCentre for Advanced Materials Processing and Manufacturing(AMPAM)QLD 4072 Australia Institute of Materials Research Helmholtz-Zentrum GeesthachtGeesthacht 21502Germany

Magnesium alloys such as Mg–Ca and Mg–Zn–Ca are good orthopaedic materials;however their tendency to corrode is high.Herein we utilize selective laser melting(SLM)to modify the surface of these Mg alloys to simultaneously improve the corrosion behaviour and microhardness.The corrosion rate decreased from 2.1±0.2 mm/y to 1.0±0.1 mm/y for the laser-processed Mg–0.6Ca,and from 1.6±0.1 mm/y to 0.7±0.2 mm/y for laser-processed Mg–0.5Zn–0.3Ca.The microhardness increased from 46±1 HV to 56±1 HV for Mg–0.6Ca,and from 47±3 HV to 55±3 HV for Mg–0.5Zn–0.3Ca.In addition,good biocompatibility remained in the laser processed Mg alloys.The improved properties are attributed to laser-induced grain refinement,confined impurity elements,residual stress,and modified surface chemistry.The results demonstrated the potential of SLM as a surface engineering approach for developing advanced biomedical Mg alloys.

关键词： Mg alloys Selective laser melting Surface modification Corrosion behaviour Microhardness

History of Geology in Norden

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Episodes 2008年第1期31卷 185-192页

作者： bjoern Sundquist Ilmari Haapala Jens Morten Hansen Geir Hestmark Sigurdur Steinthorsson Department of Earth Sciences Uppsala University Villavaegen 16 SE-75236 Uppsala Sweden. Department of Geology University of Helsinki P.O.Box 64 FI-00014 Helsinki Finland. Geological Survey of Denmark and Greenland （GEUS） Фster Voldgade 10 DK-1350 KCbenhavn K Denmark. Institute of Biology University of Oslo P.O.Box 1066 Blindern NO-0316 Oslo Norway. Department of Earth Sciences University of Iceland Jardarhaga 2-6 IS-107 Reykjavfk Iceland.

The Nordic countries of Denmark, Finland, Iceland, Norway, and Sweden have been closely connected for many centuries, not least from a geological point of view. Scientific cooperation as well as contentions have been common. The earliest known records of "geological" treatises are from the 16th century, but especially in the 18th century, when the natural sciences flourished all over Europe, Nordic scholars were in the forefront in geochemistry, mineralogy, and paleontology. This was also the century when "geology" started to be taught at the universities, and science academies were founded in Norden, adding greatly to "geological" studies. In the 19th century, like in so many other countries, national geological survey organizations and geological societies were founded. In Norden, geological research has long traditions within mineralogy and ore geology, paleontology and stratigraphy, tectonics and structural geology. During the last century, focus has turned also to Quaternary and glacial geology, igneous and metamorphic petrology, geochemistry, micropaleontology, petroleum geology, sedimentology, marine geology, geophysics, geochronology, and research related to geothermal energy and deposition of radioactive waste products. In many of these research areas. Nordic geo-scientists have contributed greatly over the years to the development of the science of geology.

关键词：地质学北欧国家地球化学矿物学

Preoperative Prediction of Lymph Node Metastasis in Colorectal Cancer with Deep Learning

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Biomedical Engineering Frontiers 2022年第1期3卷 93-104页

作者： Hailing Liu Yu Zhao Fan Yang Xiaoying Lou Feng Wu Hang Li Xiaohan Xing Tingying Peng bjoern Menze Junzhou Huang Shujun Zhang Anjia Han Jianhua Yao Xinjuan Fan Department of Pathology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510655China AI Lab TencentShenzhen 518057China Department of Computer Science Technical University of MunichMunich 85748Germany Department of Computer Science Xiamen UniversityXiamen 361005China Department of Electronic Engineering The Chinese University of Hong KongHong Kong 999077China Institute of Computational Biology Helmholtz Zentrum MünchenNeuherberg 85764Germany Helmholtz AI Helmholtz Zentrum MünchenNeuherberg 85764Germany Department of Quantitative Biomedicine University of ZurichZurich 8091Switzerland Department of Pathology The Fourth Hospital of Harbin Medical UniversityHarbin 150001China Department of Pathology The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China

Objective.To develop an artificial intelligence method predicting lymph node metastasis(LNM)for patients with colorectal cancer(CRC).Impact Statement.A novel interpretable multimodal AI-based method to predict LNM for CRC patients by integrating information of pathological images and serum tumor-specific biomarkers.Introduction.Preoperative diagnosis of LNM is essential in treatment planning for CRC patients.Existing radiology imaging and genomic tests approaches are either unreliable or too costly.Methods.A total of 1338 patients were recruited,where 1128 patients from one centre were included as the discovery cohort and 210 patients from other two centres were involved as the external validation cohort.We developed a Multimodal Multiple Instance Learning(MMIL)model to learn latent features from pathological images and then jointly integrated the clinical biomarker features for predicting LNM status.The heatmaps of the obtained MMIL model were generated for model interpretation.Results.The MMIL model outperformed preoperative radiology-imaging diagnosis and yielded high area under the curve(AUCs)of 0.926,0.878,0.809,and 0.857 for patients with stage T1,T2,T3,and T4 CRC,on the discovery cohort.On the external cohort,it obtained AUCs of 0.855,0.832,0.691,and 0.792,respectively(T1-T4),which indicates its prediction accuracy and potential adaptability among multiple centres.Conclusion.The MMIL model showed the potential in the early diagnosis of LNM by referring to pathological images and tumor-specific biomarkers,which is easily accessed in different institutes.We revealed the histomorphologic features determining the LNM prediction indicating the model ability to learn informative latent features.

关键词： diagnosis centre latent