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Machine-learning driven global optimization of surface adsorbate geometries

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npj Computational Materials 2023年第1期9卷 1196-1203页

作者： Hyunwook Jung Lena Sauerland Sina Stocker Karsten Reuter johannes T.Margraf Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6D-14195 BerlinGermany

The adsorption energies of molecular adsorbates on catalyst surfaces are key descriptors in computational catalysis *** the relatively large reaction intermediates frequently encountered,e.g.,in syngas conversion,a multitude of possible binding motifs leads to complex potential energy surfaces(PES),*** implies that finding the optimal structure is a difficult global optimization problem,which leads to significant uncertainty about the stability of many *** tackle this issue,we present a global optimization protocol for surface adsorbate geometries which trains a surrogate machine learning potential *** approach is applicable to arbitrary surface models and adsorbates and minimizes both human intervention and the number of required DFT calculations by iteratively updating the training set with configurations explored by the *** demonstrate the efficiency of this approach for a diverse set of adsorbates on the Rh(111)and(211)surfaces.

关键词： optimization global implies

Contact tracing-Old models and new challenges

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Infectious Disease Modelling 2021年第1期6卷 222-231页

作者： johannes Müller Mirjam Kretzschmar Mathematical Institute Technical University of MunichBoltzmannstr.385748GarchingGermany Institute for Computational Biology Helmholtz Center Munich85764NeuherbergGermany Julius Center for Health Sciences and Primary Care University Medical Center UtrechtUtrecht UniversityHeidelberglaan 1003584CXUtrechtthe Netherlands

Contact tracing is an effective method to control emerging infectious *** the 1980’s,modellers are developing a consistent theory for contact tracing,with the aim to find effective and efficient implementations,and to assess the effects of contact tracing on the spread of an infectious *** the progress made in the area,there remain important open *** addition,technological developments,especially in the field of molecular biology(genetic sequencing of pathogens)and modern communication(digital contact tracing),have posed new challenges for the modelling *** the present paper,we discuss modelling approaches for contact tracing and identify some of the current challenges for the field.

关键词： Contact tracing Mathematical models

The Combinatorial Approach to Asymmetric Hydrogenation: More Miles out of Monophos

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复旦学报（自然科学版） 2005年第5期44卷 829-830页

作者： johannes G. de Vries DSM Research DSM Pharma Chemicals-Advanced Synthesis Catalysis & Development P.O. Box 18 6160 MD Geleen The Netherlands.

In custom manufacturing time-to-market is of overriding importance. Thus, asymmetric hydrogenation will be applied only if an appropriate catalyst can be found in a very short period of time. For this reason we have build up a full-scale capability for High Throughput Experimentation, encompassing several robot systems. As ligand synthesis was the last remaining barrier we have explored, together with the University of Groningen, the use of simple monodentate ligands, such as MonoPhosTM. These ligands can be synthesised in two chemical steps, from BINOL, PCl3 and an ***, very high enantioselectivities can be obtained in the asymmetric hydrogenation of α-and β-dehydro-amino acids and esters, aromatic enamides, itaconic acid and ester[1]. See Scheme 1 and 2(at page 830).

关键词：加氢催化同质催化剂铑氨基磷酸脂

Effect of bed load supply on sediment transport in mountain streams

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International Journal of Sediment Research 2017年第2期32卷 240-252页

作者： johannes Kammerlander Bernhard Gems Daniel Kβler Markus Aufleger Unit of Hydraulic Engineering University of Innsbruck Austrian Research Centre for Forests Department of Natural Hazards 3. BERNARD Ingenieure ZT GmbH

Mountain streams with their tributary torrents build the upper part of the fluvial *** are important regarding the transfer of sediment from headwaters to lower *** are typically steep with wide grain size distributions,ranging from fine sand up to large boulders,and a stabilized bed *** streams often are supply-limited with respect to mobile bed load,which needs to be addressed when bed load transport equations are applied to such *** better understand supply limitation,laboratory experiments highlighting the effect of bed load supply on incipient motion and bed load transport rate are *** tests were done in which fine bed load was supplied to a previously armored channel bed,with flow conditions ranging from one-third to twice the critical discharge for the bed *** flows not exceeding the critical discharge,the time series of the bed load transport rate at the downstream model boundary featured consistent patterns which are attributed to distinct phases:(i) a temporal lag,(ii) an equilibrium state,and(iii) a post-supply *** load transport occurred even at flows distinctly below that for incipient motion of the bed ***,with the mass of total bed load outflow approaching the supply amount,the mass did not exclusively consist of supplied *** coarser the supplied bed load,the more sediment was mobilized from the bed *** higher flows,processes *** bed load outflow exceeded the supply amount and the break-up of the armor layer caused a refining of the bed surface.

关键词： Bed load transport Bed load supply Mountain stream Experimental modeling

Autoantibodies in primary sclerosing cholangitis

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World Journal of Gastroenterology 2008年第24期14卷 3781-3791页

作者： johannes Roksund Hov Kirsten Muri Boberg Tom H Karlsen Medical Department Rikshospitalet University Hospital

The aetiology of primary sclerosing cholangitis (PSC) is not known and controversy exists as to whether PSC should be denominated an autoimmune disease. A large number of autoantibodies have been detected in PSC patients,but the specifi city of these antibodies is generally low,and the frequencies vary largely between different studies. The presence of autoantibodies in PSC may be the result of a nonspecifi c dysregulation of the immune system,but the literature in PSC points to the possible presence of specifi c antibody targets in the biliary epithelium and in neutrophil granulocytes. The present review aims to give an overview of the studies of autoantibodies in PSC,with a particular emphasis on the prevalence,clinical relevance and possible pathogenetic importance of each individual marker.

关键词： Primary sclerosing cholangitis,Autoantibodies, Autoimmunity Antibodies againstcytoplasmic constituents of neutrophil, Tropomyosin

三氧化钨催化糖分子选择裂解新机理及其对生物质利用的重要意义

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Chinese Journal of Catalysis 2023年第3期46卷 1-3页

作者： johannes A.Lercher 德国慕尼黑工业大学德国加兴美国西北太平洋国家实验室美国里奇兰

糖类化合物催化转化合成燃料和化学品为现有化石路线提供了可行的替代方案.碳化钨、氧化钨和钨酸等钨基催化剂具有催化糖分子碳-碳键选择性断裂生成乙二醇、丙二醇等C_(2,3)产物的独特性能.然而,对该催化反应的机理还一直缺乏明确的认识... 详细信息

糖类化合物催化转化合成燃料和化学品为现有化石路线提供了可行的替代方案.碳化钨、氧化钨和钨酸等钨基催化剂具有催化糖分子碳-碳键选择性断裂生成乙二醇、丙二醇等C_(2,3)产物的独特性能.然而,对该催化反应的机理还一直缺乏明确的认识.最近北京大学刘海超团队报道,糖分子的羰基、α-和β-羟基与三氧化钨(WO_(3))表面的两个邻近钨原子(W-O-W结构)配位,形成一种双钨三齿螯合物;该螯合物作为反应的关键中间体,引发羰基β-位的碳-碳键断裂,从而实现糖分子的选择裂解.该新反应机理不仅为糖化学提供了新的认识,而且为糖基生物质提供了一个经乙醇醛、甘油醛等C_(2,3)中间体转化为化学品的有效策略.固体核磁表征结果表明,吸附到WO_(3)表面的^(13)Cc标记葡萄糖的C1、C2和C3三个碳原子与表面钨原子形成了C-O-W键,从而在去屏蔽作用下化学位移向低场移动,说明糖分子需要羰基以及α-和β-羟基三个官能团共同参与才具有反应活性.催化反应结果表明,含有W-O-W结构的钨基化合物均表现出催化糖分子裂解生成C_(2,3)产物的活性,例如:仲钨酸铵、磷钨酸盐和钨青铜等均相、多相催化剂都能有效地将葡萄糖转化为乙二醇.通过理论计算分别模拟L-苏阿糖和2-脱氧-L-苏阿糖在WO_(3)(001)晶面上的反应过程,发现前者形成的L-苏阿糖-三氧化钨三齿螯合物,在后续碳-碳键选择性断裂生成一分子乙醇醛和一分子表面结合的乙烯二醇中间物种过程中,只有-0.01 eV的能量变化以及0.53 eV的能垒;而2-脱氧-L-苏阿糖则不同,由于缺乏α-羟基,后续碳-碳键断裂过程中需要吸收0.20 eV的能量和克服0.62 eV的能垒.计算结果进一步证明了糖-三氧化钨三齿螯合物中间体和糖分子α-羟基在反应中发挥了至关重要的作用.刘海超团队这项开拓性的工作揭示了三氧化钨催化糖分子碳-碳键选择性断裂的新机理,扩展了教科书中对经典逆羟醛缩合反应机理的描述.在该机理指导下,来源多样、纯度不同和结构各异的糖类化合物均能够在钨基催化剂作用下经乙醇醛和甘油醛等C_(2,3)中间体转化为化学品,从而为糖基生物质高效利用提供了具有实用意义的新策略.这正如现代石油化工所普遍采用的方法,首先将石油原料经过催化裂化或水汽裂解转化为乙烯、丙烯等C_(2,3)中间体,然后进一步转化为下游丰富的化学品.因此,该项研究工作对于纤维素、半纤维素等糖基生物质的高效转化利用具有重要意义.

关键词：生物质糖三氧化钨碳–碳键断裂非经典逆羟醛缩合反应机理

Colon capsule endoscopy: Current status and future directions

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World Journal of Gastroenterology 2014年第44期20卷 16596-16602页

作者： Andrea O Tal johannes Vermehren J?rg G Albert Department of Internal Medicine I University Hospital Frankfurt

Colon capsule endoscopy(CCE; Pill Cam Colon; Given Imaging; Yoqneam, Israel) is a minimally invasive wireless technique for the visualization of the colon. With the recent introduction of the second generation colon capsule the diagnostic accuracy of CCE for polyp detection has significantly improved and preliminary data suggest it may be useful to monitor mucosal inflammation in patients with inflammatory bowel disease. Limitations include the inability to take biopsies and the procedural costs. However, given the potentially higher acceptance within an average risk colorectal cancer(CRC) screening population, its usefulness as a screening tool with regard to CRC prevention should be further evaluated.

关键词： Capsule endoscopy Endoscopy Colon capsule endoscopy Colonoscopy Colorectal cancer Colon Colonic capsule endoscopy Inflammatory bowel disease

Predicting the next move: tracking the complexity of lung cancer evolution and metastasis

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Signal Transduction and Targeted Therapy 2023年第9期8卷 3885-3887页

作者： Carina Lorenz Axel M.Hillmer johannes Brägelmann University of Cologne Faculty of Medicine and University Hospital CologneDepartment of Translational GenomicsCologneGermany University of Cologne Faculty of Medicine and University Hospital CologneMildred Scheel School of Oncology CologneCologneGermany University of Cologne Faculty of Medicine and University Hospital CologneCenter for Molecular Medicine CologneCologneGermany University of Cologne Faculty of Medicine and University Hospital CologneInstitute of PathologyCologneGermany

In a series of seven papers in Nature and Nature Medicine,the TRACERx study group presents multi-omic analyses of 421 non-small cell lung cancer(NSCLC)patients,which have yielded a comprehensive map of intratumor heterogeneity(ITH)and lung cancer evolutionary trajectories at an unprecedented level of detail.1–7 The in-depth molecular data,and their subsequent integrated analyses,hold the potential to not only shine light on lung cancer progression but also influence a broad spectrum of scientific disciplines,research fields,and clinical oncology,thereby enhancing our understanding of cancer in general.

关键词： lung cancer metastasis

Noni juice is not hepatotoxic

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World Journal of Gastroenterology 2006年第22期12卷 3616-3619页

作者： Brett J West C Jarakae Jensen johannes Westendorf Research and Development Department Tahitian Noni International American ForkUtahUnited States University Medical School of Hamburg Department of Toxicology HamburgGennany

Noni juice （Morinda citrifolia） has been approved for use as a safe food within the European Union, following a review of safety. Since approval, three cases of acute hepatitis in Austrian noni juice consumers have been published, where a causal link is suggested between the liver dysfunction and ingestion of anthraquinones from the plant. Measurements of liver function in a human clinical safety study of TAHITIAN NONI Juice, as well as subacute and subchronic animal toxicity tests revealed no evidence of adverse liver effects at doses many times higher than those reported in the case studies. Additionally, M. citrifolia anthraquinones occur in the fruit in quantities too small to be of any toxicological significance. Further, these do not have chemical structures capable of being reduced to reactive anthrone radicals, which were implicated in previous cases of herbal hepototoxicity. The available data reveals no evidence of liver toxicity.

关键词： Noni juice Morinda citrifolia Novel food Human clinical safety study