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Finite size specimens with cracks of icosahedral Al Pd Mn quasicrystals

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Chinese Physics B 2014年第5期23卷 404-413页

作者：杨连枝 Ricoeur andreas 何蕃民高阳 College of Science China Agricultural University College of Engineering China Agricultural University Institute of Mechanics University of Kassel Sichuan Hydropower Investment & Management Group LTD

Icosahedral quasicrystals are the most important and thermodynamically stable in all about 200 kinds of quasicrystals currently observed. Beyond the scope of classical elasticity, apart from a phonon displacement field, there is a phason displacement field in the elasticity of the quasicrystal, which induces an important effect on the mechanical properties of the material and makes an analytical solution difficult to obtain. In this paper, a finite element algorithm for the static elasticity of icosahedral quasicrystals is developed by transforming the elastic boundary value problem of the icosahedral quasicrystals into an equivalent variational problem. Analytical and numerical solutions for an icosahedral A1-Pd-Mn quasicrystal cuboid subjected to a uniaxial tension with different phonon-phason coupling parameters are given to verify the validity of the numerical approach. A comparison between the analytical and numerical solutions of the specimen demonstrates the accuracy and efficiency of the present algorithm. Finally, in order to reveal the fracture behavior of the icosahedral A1-Pd-Mn quasicrystal, a cracked specimen with a finite size of matter is investigated, both with and without phonon-phason coupling. Meanwhile, the geometry factors are calculated, including the stress intensity factor and the crack opening displacement for the finite-size specimen. Computational results reveal the importance of pbonon-phason coupling effect on the icosahedral A1-Pd-Mn quasicrystal. Furthermore, the finite element procedure can be used to solve more complicated boundary value problems.

关键词： icosahedral quasicrystals finite-size crack specimen finite element method cuboid

Combining High-Resolution Imaging,Deep Learning,and Dynamic Modeling to Separate Disease and Senescence in Wheat Canopies

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Plant Phenomics 2023年第2期5卷 295-312页

作者： Jonas Anderegg Radek Zenkl Achim Walter andreas Hund Plant Pathology Group Institute of Integrative BiologyETH ZurichZurichSwitzerland Crop Science Group Institute of Agricultural SciencesETH ZurichZurichSwitzerland

Maintenance of sufficiently healthy green leaf area after anthesis is key to ensuring an adequate assimilate supply for grain *** regulated age-related physiological senescence and various biotic and abiotic stressors drive overall greenness decay dynamics under field *** direct effects on green leaf area in terms of leaf damage,stressors often anticipate or accelerate physiological senescence,which may multiply their negative impact on grain ***,we present an image processing methodology that enables the monitoring of chlorosis and necrosis separately for ears and shoots(stems+leaves)based on deep learning models for semantic segmentation and color properties of vegetation.A vegetation segmentation model was trained using semisynthetic training data generated using image composition and generative adversarial neural networks,which greatly reduced the risk of annotation uncertainties and annotation *** of the models to image time series revealed temporal patterns of greenness decay as well as the relative contributions of chlorosis and ***-based estimation of greenness decay dynamics was highly correlated with scoring-based estimations(r≈0.9).Contrasting patterns were observed for plots with different levels of foliar diseases,particularly septoria tritici *** results suggest that tracking the chlorotic and necrotic fractions separately may enable(a)a separate quantification of the contribution of biotic stress and physiological senescence on overall green leaf area dynamics and(b)investigation of interactions between biotic stress and physiological *** high-throughput nature of our methodology paves the way to conducting genetic studies of disease resistance and tolerance.

关键词： Wheat enable image

Role of minimally invasive surgery for rectal cancer

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World Journal of Gastroenterology 2020年第30期26卷 4394-4414页

作者： Kurt A Melstrom andreas M Kaiser Division of Colorectal Surgery Department of SurgeryCity of Hope National Medical CenterDuarteCA 91010-3000United States

Rectal cancer is one of the most common malignancies *** resection for rectal cancer usually requires a proctectomy with respective lymphadenectomy(total mesorectal excision).This has traditionally been performed transabdominally through an open *** the last thirty years,minimally invasive surgery platforms have rapidly evolved with the goal to accomplish the same quality rectal resection through a less invasive *** are currently three resective modalities that complement the traditional open operation:(1)Laparoscopic surgery;(2)Robotic surgery;and(3)Transanal total mesorectal *** addition,there are several platforms to carry out transluminal local excisions(without lymphadenectomy).Evidence on the various modalities is of mixed to moderate *** is unreasonable to expect a randomized comparison of all options in a single *** review aims at reviewing in detail the various techniques in regard to intra-/perioperative benchmarks,recovery and complications,oncological and functional outcomes.

关键词： Rectal cancer Minimally invasive surgery Laparoscopic surgery Robotic surgery Transanal total mesorectal excision Transanal minimally invasive surgery

Tailored surface textures to increase friction-A review

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Friction 2022年第9期10卷 1285-1304页

作者： Henara L.COSTA Jörg SCHILLE andreas ROSENKRANZ School of Engineering Surface Engineering GroupUniversidade Federal do Rio GrandeRio Grande 96203900Brazil University of Applied Sciences Mittweida Laserinstitut Hochschule Mittweida 09648Germany Department of Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiago 8370459Chile

Surface textures with micro-scale feature dimensions still hold great potential to enhance the frictional performance of tribological *** from the ability of surface texturing to reduce friction,surface textures can also be used to intentionally increase friction in various applications that rely on friction for their adequate ***,this review aims at presenting the state-of-the-art regarding textured surfaces for high-friction *** a brief general introduction,the recent trends and future paths in laser surface texturing are ***,the potential of surface textures to increase friction in different applications including adhesion,movement transmission and control,biomimetic applications,and road-tire contacts is critically *** emphasis in this section is laid on the involved mechanisms responsible for friction ***,current short-comings and future research directions are pointed out thus emphasizing the great potential of(laser-based)surface texturing methods for innovations in modern surface engineering.

关键词： surface texturing tribology laser processing friction increase

Recent Developments in the Chemistry of Woody Odorants

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复旦学报（自然科学版） 2005年第5期44卷 777-778页

作者： andreas Goeke Shanghai Givaudan Ltd Pu Dong Zhangjiang High-Tech Park 298 Li Shi-zhen Road Shanghai 201203 China

Woody odorants constitute an important olfactory family in perfumery[1]. Essential wood oils, traditionally being obtained by steam distillation of plant materials, are extensively being used in a variety of *** oil (e. g. in "Gentlemen", Givenchy), vetiver oil ("Vetiver", J. P. Guerlain) and cedar wood oil ("Déclaration", Cartier) are classics in this field. On the other hand, many terpenic hydrocarbons which are perse not particularly useful as perfume ingredients, have been functionalized in order to obtain more sophisticated scents. Javanol(R), Belambre(R), Ysamber K(R) and Ambrocenide(R) (prepared from pinene, camphor,logifolene and cedrene) are the names of potent and recently commercialized wood odorants. However, due to variable qualities of the natural starting materials, it has been an important task in fragrance research to find inexpensive but fully synthetic alternatives which, in light of the complexity of the structures, remains challenging. See Fig. 1.

关键词：木制香料嗅觉阳离子环化作用氢化物

Organocatalytic Domino-methylenation/Diels-Alder Reactions

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复旦学报（自然科学版） 2007年第5期46卷 600-601页

作者： andreas Goeke Shanghai Givaudan Ltd Pu Dong Zhang Jiang High-Tech Park

1 Results Organocatalytic reactions are currently very much en vogue as the term implies a connotation of ecologically benign *** addition,beautiful new results have been achieved over the last few years which triggered a dramatic increase in publications[1].Related to this topic is the catalysis of organic transformations by hydrogen bond donors and organic Brnsted acids[2].From an industrial point of view,these reactions can be beneficial when performed in water in high concentration,prerequ...

关键词： Diels-Alder organocatalysis methylenation selectivity odor

Educating Learners for Their Future,Not Our Past

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ECNU Review of Education 2018年第1期1卷 58-75页

作者： andreas Schleicher The Organization for Economic Co-operation and Development(OECD)

Purpose-This paper aims to examine the educational demands in the digital age from tomorrow’s teachers and policy-makers,and to encourage and incentivize all actors to develop the innovative learning environments that we need for tomorrow’s ***/Approach/Methods-As a conceptual paper,this article has consulted and analyzed a wide range of updated data and literature to consolidate the argumentation on tomorrow’s educational ***-The paper mainly provides possible answers on how to educate students for their future,rather than our *** heart of future education is to help students develop a reliable compass and tools,transformative competency,and to navigate through an increasingly complex,volatile,and uncertain *** fulfill this core mission,a new set of curriculum design principles,changing school system,renewed teacher culture,and an alternative assessment program are highly ***/Value-Based on the latest observations and reflections,the paper broadens our visions on tomorrow’s education and future schools.

关键词： Transformative competencies learning compass school system professional development

Ischemic long-term-potentiation(iLTP): perspectives to set the threshold of neural plasticity toward therapy

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Neural Regeneration Research 2015年第10期10卷 1537-1539页

作者： Maximilian Lenz andreas Vlachos Nicola Maggio Department of Neurology The J.Sagol Neuroscience Center The Chaim Sheba Medical Center Institute of Clinical Neuroanatomy Neuroscience Center Frankfurt Goethe-University Frankfurt Talpiot Medical Leadership Program The Chaim Sheba Medical Center

The precise role of neural plasticity under pathological conditions remains not well understood. It appears to be well accepted, however, that changes in the ability of neurons to express plasticity accompany neurological diseases. Here, we discuss recent experimental evidence, which suggests that synaptic plasticity induced by a pathological stimulus, i.e., ischemic long-term-potentiation（i LTP） of excitatory synapses, could play an important role for post-stroke recovery by influencing the post-lesional reorganization of surviving neuronal networks.

关键词： ischemic LTP(iLTP) stroke neural repair synaptic plasticity neural homeostasis

Liver transplantation for severe hepatic trauma:Experience from a single center

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World Journal of Gastroenterology 2009年第13期15卷 1641-1644页

作者： Spiros G Delis andreas Bakoyiannis Gennaro Selvaggi Debbie Weppler David Levi andreas G Tzakis Department of Surgery Division of TransplantationUniversity of Miami Miller School of Medicine

Liver transplantation has been reported in the literature as an extreme intervention in cases of severe and complicated hepatic *** main indications for liver transplant in such cases were uncontrollable bleeding and postoperative hepatic *** here describe four cases of orthotopic liver transplantation after penetrating or blunt liver *** indications were liver failure,extended liver necrosis,liver gangrene and multiple episodes of gastrointestinal bleeding related to portal hypertension,*** patient died due to postoperative cerebral *** other three patients recovered well and remain on *** transplantation should be considered as a saving procedure in severe hepatic trauma,when all other treatment modalities fail.

关键词： Liver injury Orthotopic liver transplantation Severe liver trauma Hepatic coma Hepatic trauma