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3D U-Net Segmentation Improves Root System Reconstruction from 3D MRI Images in Automated and Manual Virtual Reality Work Flows

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Plant Phenomics 2023年第3期5卷 598-611页

作者： tobias Selzner Jannis Horn Magdalena Landl Andreas Pohlmeier Dirk Helmrich Katrin Huber Jan Vanderborght Harry Vereecken Sven Behnke Andrea Schnepf Forschungszentrum Juelich GmbH Agrosphere(IBG-3)JuelichGermany Autonomous Intelligence Systems Group University of BonnBonnGermany Forschungszentrum Juelich GmbH Juelich Supercomputing CenterJuelichGermany

Magnetic resonance imaging(MRI)is used to image root systems grown in opaque ***,reconstruction of root system architecture(RSA)from 3-dimensional(3D)MRI images is *** resolution and poor contrast-to-noise ratios(CNRs)hinder automated ***,manual reconstruction is still widely ***,we evaluate a novel 2-step work flow for automated RSA *** the first step,a 3D U-Net segments MRI images into root and soil in *** the second step,an automated tracing algorithm reconstructs the root systems from the segmented *** evaluated the merits of both steps for an MRI dataset of 8 lupine root systems,by comparing the automated reconstructions to manual reconstructions of unaltered and segmented MRI images derived with a novel virtual reality *** found that the U-Net segmentation offers profound benefits in manual reconstruction:reconstruction speed was doubled(+97%)for images with low CNR and increased by 27%for images with high *** root lengths were increased by 20%and 3%,***,we propose to use U-Net segmentation as a principal image preprocessing step in manual work *** root length derived by the tracing algorithm was lower than in both manual reconstruction methods,but segmentation allowed automated processing of otherwise not readily usable MRI ***,model-based functional root traits revealed similar hydraulic behavior of automated and manual *** studies will aim to establish a hybrid work flow that utilizes automated reconstructions as scaffolds that can be manually corrected.

关键词： Root utilize otherwise

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Can minimal running shoes imitate barefoot heel-toe running patterns?A comparison of lower leg kinematics

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Journal of Sport and Health Science 2014年第2期3卷 67-73,152+156页

作者： tobias Hein Stefan Grau Department of Food and Nutrition and Sport ScienceUniversity of Gothenburg Medical Clinic Department of Sports MedicineUniversity of Tuebingen

Background:Numerous studies about the interaction between footwear(and barefoot) and kinematic and kinetic outcomes have been published over the last few *** studies however lead to the conclusion that the assumed interactions depend mainly on the subjects" experience of barefoot(BF) walking/running,the preferred running strike pattern,the speed,the hardness of the surface,the thickness of the midsole material,and the runners’ level of *** aim of the present study was to investigate lower leg kinematics o\’ BF running and running in minimal running shoes(MRS) to assess comparability of BF kinematics in both *** systematically compare both conditions we monitored the influencing variables described above in our measurement *** hypothesized that running in MRS does not alter lower leg kinematics compared to BF ***:Thirty-seven subjects,injury-free and active in sports,ran BF on an EVA foam runway,and also ran shod wearing Nike Free 3.0 on a tartan indoor ***-leg 3D kinematics was measured to quantify rearfoot and ankle *** markers were used in both shod and BF ***:All runners revealed rearfoot strike pattern when running *** between BF and MRS running occurred particularly during the initial stance phase of running,both in the sagittal and the frontal *** running revealed a flatter foot placement,a more plantar flexed ankle joint and less inverted rearfoot at touchdown compared to MRS ***:BF running does not change the landing automatically to forefoot running,especially after a systematic exclusion of surface and other influencing *** Nike Free 3.0 mimics some BF ***,changes in design of the Nike Free should be considered in order to mimic BF movement even more closely.

关键词： 3D-kinematics Ankle Barefoot Minimal running shoes Rearfoot Running

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Photonic molecules with a tunable inter-cavity gap

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Light(Science & Applications) 2016年第1期5卷 195-201页

作者： tobias Siegle Stefan Schierle Sarah Kraemmer Benjamin Richter Sentayehu F Wondimu Peter Schuch Christian Koos Heinz Kalt Institute of Applied Physics Karlsruhe Institute of Technology(KIT)76128 KarlsruheGermany Zoological Institute Karlsruhe Institute of Technology(KIT)76128 KarlsruheGermany Institute of Microstructure Technology Karlsruhe Institute of Technology(KIT)76128 KarlsruheGermany Institute of Photonics and Quantum Electronics Karlsruhe Institute of Technology(KIT)76128 KarlsruheGermany

Optical micro-resonators have broad *** are used,for example,to enhance light–matter interactions in optical sensors or as model systems for investigating fundamental physical mechanisms in cavity quantum *** two or more micro-cavities is particularly interesting as it enlarges the design freedom and the field of *** this context,achieving tunability of the coupling strength and hence the inter-cavity gap is of utmost importance for adjusting the properties of the coupled micro-resonator *** this paper,we report on a novel coupling approach that allows highly precise tuning of the coupling gap of polymeric micro-resonators that are fabricated side by side on a common *** structure goblet-shaped whispering-gallery-mode resonators on an elastic silicone-based polymer substrate by direct laser *** silicone substrate is mechanically stretched in order to exploit the lateral shrinkage to reduce the coupling *** a laser dye into the micro-resonators transforms the cavities into micro-lasers that can be pumped *** have investigated the lasing emission by micro-photoluminescence spectroscopy,focusing on the spatial localization of the *** results demonstrate the formation of photonic molecules consisting of two or even three resonators,for which the coupling strengths and hence the lasing performance can be precisely *** and tunability are key elements in future photonics,making our approach interesting for various photonic *** instance,as our coupling approach can also be extended to larger cavity arrays,it might serve as a platform for tunable coupled-resonator optical waveguide devices.

关键词： coupled resonators photonic molecules micro-lasers tunable coupling gap whispering gallery mode resonators

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Bravo capsule system optimizes intragastric pH monitoring over prolonged time:Effects of ghrelin on gastric acid and hormone secretion in the rat

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World Journal of Gastroenterology 2008年第40期14卷 6180-6187页

作者： tobias Rudholm Per Mikael Hellstrm Elvar Theodorsson Colin Allan Campbell Peter Geoffrey McLean Erik Nslund Department of Medicine Solna Karolinska Institutet Department of Neurochemistry Linkping University Hospital Neurology and GI CEDD GlaxoSmithKlineHarlowUKEssex CM19 5AWUnited Kingdom Division of Surgery Department of Clinical SciencesDanderyd HospitalKarolinska Institutet

AIM: To evaluate measurements of intragastric pH with the Bravo capsule system over a prolonged ***: A Bravo capsule was placed inside the rat gastric body and pH was studied for periods up to five consecutive *** comparison,a gastric fistula model was *** of ghrelin and esomeprazole,with or without pentagastrin,on gastric pH were *** addition,effects of esomeprazole on plasma ghrelin,gastrin and somatostatin were ***: All rats recovered after *** average 24-h pH during free feeding was 2.3 ± 0.1 (n = 20) with a variation of 18% ± 6% over 5 ***,2400 pmol/kg,*** pH from 1.7 ± 0.1 to 3.1 ± 0.3 (P < 0.01) as recorded with the Bravo *** esomeprazole (1 mg/kg,3 mg/kg and 5 mg/kg) there was a dose-dependent pH increase of maximally 3.4 ± 0.1,with day-to-day variation over the entire period of 8% ± 3%.The fistula and pH studies generated similar *** inhibition with esomeprazole increased plasma ghrelin from 10 ± 2 pmol/L to 65 ± 26 pmol/L (P < 0.001),and somatostatin from 10 ± 2 pmol/L to 67 ± 18 pmol/L (P < 0.001).CONCLUSION: pH measurements with the Bravo capsule are reliable,and comparable to those of the gastric fistula *** Bravo system optimizes accurate intragastric pH monitoring over prolonged periods and allows both short-and long-term evaluation of effects of drugs and hormones.

关键词： Gastric acid Bravo system Intragastric pH, Ghrelin Somatostatin

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Drought sensitivity of beech on a shallow chalk soil in northeastern Germany - a comparative study

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Forest Ecosystems 2017年第1期4卷 45-54页

作者： Marieke van der Maaten-Theunissen Hanna Bummerstede Janette Iwanowski tobias Scharnweber Martin Wilmking Ernst van der Maaten Institute of Botany and Landscape Ecology University of Greifswald Soldmannstr 15 17487 Greifswald Germany

Background： We compare the climate sensitivity of European beech （Fagus sylvatica L.） in two forest nature reserves in northeastern Germany. The one reserve, Schlossberg, is characterized by shallow chalk soils, whereas in the other reserve, EIdena, soils are deeper and more developed. Little is known about the drought sensitivity of beech on shallow chalk soils. Methods： We collected increment cores at both research sites and established climate-growth relationships. Inter- tree variability was assessed by employing linear mixed-effect models. Results： We expected to find distinctively higher drought sensitivity at Schlossberg due to limited water availability, but find only marginal differences in growth responses. At both sites, drought is the major climatic factor driving tree growth. Adaptations in tree architecture and an underestimation of the water holding capacity of shallow chalk soils are discussed as possible reasons for not finding more distinct climate responses. In analyzing climate-growth relationships, we specifically focused on growth responses of individual trees but observed only low inter-tree variability at both sites. Evident is a shift in climate response patterns from the first to the second half of the twentieth century with previous-year drought conditions becoming more important than current-year drought. This shift is discussed in relation to a warming trend over that same period, as well as possible trends in masting behavior of beech. Conclusion： The investigated beech trees on the shallow chalk soil are only slightly more drought sensitive than beech trees on the reference site with deeper and more developed soils.

关键词： Climate-growth relationships Dendroecology Inter-tree variability Temporal stability Drought stress

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电动车尾门电动推杆用低音调齿轮的开发与验证

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同济大学学报（自然科学版） 2021年第S1期49卷 108-113页

作者：任亚雄 HECHT Matthias ADAMS Christian MELZ tobias 达姆施塔特工业大学系统可靠性、自适应结构和机械声学研究组德国达姆施塔特64287 弗劳恩霍夫结构耐用性和系统可靠性研究所德国达姆施塔特64289

高速电动机目前被广泛用于汽车自主驾驶系统。由于高速电动机采用小质量设计,因此为了使转速和输出扭矩达到目标值,通常将渐开线齿轮组和它配套使用。然而,传统的渐开线齿轮在工作中噪声较大,因此一种新型的具有不规则轮齿设计的低音调(... 详细信息

高速电动机目前被广泛用于汽车自主驾驶系统。由于高速电动机采用小质量设计,因此为了使转速和输出扭矩达到目标值,通常将渐开线齿轮组和它配套使用。然而,传统的渐开线齿轮在工作中噪声较大,因此一种新型的具有不规则轮齿设计的低音调(Low⁃Tone)齿轮被开发,以减少齿轮传动装置的噪声。通过优化算法,开发设计了一种Low⁃Tone齿轮,并应用于一个驱动电动车尾门启闭的电动推杆系统。之后在该系统运行期间,对使用Low⁃Tone齿轮和使用传统齿轮所产生的声压进行测量对比。结果表明,Low⁃Tone齿轮对于噪声有较好的抑制作用,其优势特别体现在音调特性方面。

关键词：低音调齿轮噪声降低音调特性

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Dexamethasone, tetrahydrobiopterin and uncoupling of endothelial nitric oxide synthase

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Journal of Geriatric Cardiology 2015年第5期12卷 528-539页

作者： Silke tobias Alice Habermeier Daniel Siuda Gisela Reifenberg Ning Xia Ellen I Closs Ulrich Forstermann Huige Li Department of Pharmacology Johannes Gutenberg University Medical Center Mainz Germany

Objective To find out whether dexamethasone induces an uncoupling of the endothelial nitric oxide synthase （eNOS）. Methods ＆ Results A major cause of eNOS uncoupling is a deficiency of its cofactor tetrahydrobiopterin （BH4）. Treatment of human *** 926 endothelial cells with dexamethasone decreased mRNA and protein expression of both BH4-synthesizing enzymes： GTP cyclobydrolase I and dihydrofolate reductase. Consistently, a concentration- and time-dependent reduction of BH4, dihydrobiopterin （BH2） as well as BH4：BH2 ratio was observed in dexamethasone-treated cells. Surprisingly, no evidence for eNOS uncoupling was found. We then analyzed the expression and phosphorylation of the eNOS enzyme. Dexamethasone treatment led to a down-regulation of eNOS protein and a reduction of eNOS phosphorylation at serine 1177. A reduction of eNOS expression may lead to a relatively normal BH4： eNOS molar ratio in dexamethasone-treated cells. Because the BH4-eNOS stoichiometry rather than the absolute BH4 amount is the key determinant of eNOS functionality （i.e., coupled or uncoupled）, the down-regulation of eNOS may represent an explanation for the absence of eNOS uncoupling. Phosphorylation of eNOS at serine 1177 is needed for both the NO-producing activity of the coupled eNOS and the superoxide-producing activity of the uncoupled eNOS. Thus, a reduction of serine 1177 phosphorylation may render a potentially uncoupled eNOS hardly detectable. Conclusions Although dexamethasone reduces BH4 levels in endothelial cells, eNOS uncoupling is not evident. The reduction of NO production in dexamethasone-treated endothelial cells is mainly attributable to reduced eNOS expression and decreased eNOS phosphorylation at serine 1177.

关键词： Dexamethasone Endothelial cells eNOS uncoupling Nitric oxide synthase Reactive oxygen species Tetrahydrobiopterin

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Non-substituted fused bis-tetracene based thin-film transistor with self-assembled monolayer hybrid dielectrics

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Frontiers of Materials Science 2020年第3期14卷 314-322页

作者： Baolin Zhao Mikhail Feofanov Dominik Lungerich Hyoungwon Park tobias Rejek Judith Wittmann Marco Sarcletti Konstantin Amsharov Marcus Halik Organic Materials and Devices Institute of Polymer MaterialsDepartment of Materials ScienceFriedrich-Alexander-Universität Erlangen-NürnbergIZNF BuildingCauerstraße 391058ErlangenGermany Chair of Organic Chemistry II Friedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str.1091058ErlangenGermany Molecular Technology Innovation Presidential Endowed Chair The University of Tokyo7-3-1 HongoBunkyo-ku113-0033TokyoJapan

Polycyclic aromatic hydrocarbons with zigzag peripheries are high perspective candidates for organic ***,large fused acenes are still poorly studied due to the tedious *** we report a non-substituted fused bistetracene DBATT(2.3,8.9-dibenzanthanthrene)as the semiconductor on low-voltage-driven organic thin-film *** systematic studies of thin-film growth on various self-assembled monolayer(SAM)modified gate dielectrics and the electrical performances were carried *** sub-monolayer of the semiconductor film shows larger island domains on the alkyl chain *** device exhibits the hole mobility of 0.011 cm2·V−1·s−1 with a current ratio of IonIIoff above 105.

关键词： fused bis-tetracene organic field-effect transistor contact resistance self-assembled monolayer

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On the Separation Mechanism between a Shark’s Tooth and Its Jaw Base, with Special Emphasis on an Observation Made from a White Shark, <i>Carcharodon carcharias</i>

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Open Journal of Animal Sciences 2018年第3期8卷 329-334页

作者： Erich K. ritter Andreas Dellios Department of Mathematics & Statistics University of West Florida Pensacola FL USA Shark Research Institute Global Shark Attack File Princeton NJ USA Shark School 5970 Osprey Place Pensacola FL USA

Feeding is the likely cause for tooth shedding in sharks. Although the overall process of loosing teeth has been well studied, hardly any emphasis has been given to the actual separation mechanism between a shark’s tooth base and the surrounding jaw tissue. Attention is given to this very process, in connection to a never before videotaped tooth loss of a white shark, Carcharodon carcharias, that occurred within 0.3 seconds. Since the shark did not bite into anything prior to this observation, the cause for this tooth loss does not seem feeding but fatigue related, triggered through a combination of mechanical and potentially biochemical degradation processes.

关键词： Shark Tooth Loss Tooth Shedding White Shark

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Developing a Framework to Measure Watershed Sustainability by Using Hydrological/Water Quality Model

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Journal of Water Resource and Protection 2011年第11期3卷 788-804页

作者： Aditya Sood William F. ritter 不详

A framework is built, wherein hydrological/water quality model is used to measure watershed sustainability. For this framework, watershed sustainability has been defined and quantified by defining social, environmental and biodiversity indicators. By providing weightage to these indicators, a “River Basin Sustainability Index” is built. The watershed sustainability is then calculated based on the concepts of reliability, resilience and vulnerability. The framework is then applied to a case study, where, based on watershed management principles, four land use scenarios are created in GIS. The Soil and Water Assessment Tool (SWAT) is used as a hydrology/water quality model. Based on the results the land uses are ranked for sustainability and policy implications have been discussed. This results show that landuse (both type and location) impact watershed sustainability. The existing land use is weak in environmental sustainability. Also, riparian zones play a critical role in watershed sustainability, although beyond certain width their contribution is not significant.

关键词： Sustainability Development Framework Watershed Resilience Reliability Vulnerability Hydrological Models Application Landuse

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