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Real-Time hybrid Simulation of Seismically Isolated Structures with Full-Scale Bearings and Large Computational Models

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 693-717页

作者： Alireza Sarebanha andreas h.schellenberg Matthew J.Schoettler Gilberto Mosqueda Stephen A.Mahin Arup 900 Wilshire BoulevardLos Angeles90017USA Maffei Structural Engineering 98 Battery StSan Francisco94111USA Department of Civil and Environmental Engineering UC BerkeleyRichmond94804USA Department of Structural Engineering UC San DiegoLa Jolla92093USA

hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical *** dynamic response of a seismically isolated structure depends on the combined characteristics of the ground motion,bearings,and ***,dynamic full-scale system level tests of isolated structures under realistic dynamic loading conditions are desirable towards a holistic validation of this earthquake protection ***,bearing properties and their ultimate behavior have been shown to be highly dependent on rate-of-loading and scale size effects,especially under extreme loading *** laboratory facilities can test full-scale seismic isolation bearings under prescribed displacement and/or loading *** adaptation of a full-scale bearing test machine for the implementation of real-time hybrid simulation is presented here with a focus on the challenges encountered in attaining reliable simulation results for large scale dynamic *** advanced real-time hybrid simulations of large and complex hybrid models with several thousands of degrees of freedom are some of the first to use high performance parallel computing to rapidly execute the numerical *** in the experimental setup included measured forces contaminated by delay and other systematic control errors in applying desired *** and inertial forces generated by the large-scale loading apparatus can affect the accuracy of measured force *** results from real-time hybrid simulation requires implementation of compensation algorithms and correction of these various sources of ***,this research program confirms that real-time hybrid simulation is a viable testing method to experimentally assess the behavior of full-scale isolators while capturing interactions with the numerical models of the superstructure to evaluate

关键词： Real-time hybrid simulation seismic isolation parallel processing full scale bearing experimental testing

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina hromada Patrick heimel Markus Kerbl LászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.heinzel Antal Nógrádi andreas h.Teuschl-Woller David hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). however, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

A DIFFUSION–TRANSPORT hYBRID METhOD FOR ACCELERATING OPTICAL TOMOGRAPhY

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Journal of Innovative Optical health Sciences 2010年第4期3卷 293-305页

作者： hYUN KEOL KIM andreas h.hIELSChER Department of Biomedical Engineering Columbia University New YorkNY 10027USA Department of Radiology Columbia University New YorkNY 10032USA Department of Electrical Engineering Columbia University New YorkNY 10027USA

It is well acknowledged that the equation of radiative transfer(ERT)provides an accurate prediction of light propagation in biological tissues,while the diffusion approximation(DA)is of limited accuracy for the transport ***,ERT-based reconstruction codes require much longer computation times as compared to DA-based reconstruction *** introduce here a computationally efficient algorithm,called a diffusion–transport hybrid solver,that makes use of the DA-or low-order ERT-based inverse solution as an initial guess for the full ERT-based reconstruction *** evaluate the performance of this hybrid method,we present extensive studies involving numerical tissue phantoms and experimental *** a result,we show that the hybrid method reduces the reconstruction time by a factor of up to 23,depending on the physical character of the problem.

关键词： Optical tomography reconstruction time radiative transfer equation

Update on the management of sigmoid diverticulitis

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World Journal of Gastroenterology 2021年第9期27卷 760-781页

作者： Mark h hanna andreas M Kaiser Division of Colorectal Surgery Department of SurgeryCity of Hope National Medical CenterDuarteCA 91010-3000United States

Diverticular disease and diverticulitis are the most common non-cancerous pathology of the *** has traditionally been considered a disease of the elderly and associated with cultural and dietary *** has been a growing evolution in our understanding and the treatment guidelines for this *** provide an updated review of the epidemiology,pathogenesis,classification and highlight changes in the medical and surgical management of *** is increasingly being seen in young patients(han previously *** similarities and overlap with inflammatory bowel disease and irritable bowel syndrome *** tomography imaging represents the standard to classify the severity of *** to the traditional hinchey classification might serve to better delineate mild and intermediate forms as well as better classify chronic presentations of ***-operative management is primarily based on antibiotics and supportive measures,but antibiotics may be omitted in mild *** colonoscopy remains advisable after an acute attack,particularly after a complicated *** surgery is needed for the most severe as well as refractory cases,whereas elective resections are individualized and should be considered for chronic,smoldering,or recurrent forms and respective complications(stricture,fistula,etc.)and for patients with factors highly predictive of recurrent *** is no longer a disease of the *** evolving understanding of diverticulitis as a clinical entity has led into a more nuanced approach in both the medical and surgical management of this common ***-surgical management remains the appropriate treatment for greater than 70%of *** individuals with non-relenting,persistent,or recurrent symptoms and those with complicated disease and sequelae,a segmental colectomy remains the most effec

关键词： Diverticulitis Epidemiology Antibiotics Surgical resection Laparoscopic lavage Classification

Source-specific risk assessment for cadmium in wheat and maize:Towards an enrichment model for China

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Journal of Environmental Sciences 2023年第3期125卷 723-734页

作者： Zhong Zhuang Qiqi Wang Siyu huang Andrea Giovanna NinoSavala Yanan Wan huafen Li andreas h.Schweiger andreas Fangmeier Jürgen Franzaring Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Key Laboratory of Plant-Soil Interactions of the Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001China Institute of Landscape and Plant Ecology University of Hohenheim70599 StuttgartGermany

Cadmium (Cd) pollution of agricultural soil is of public concern due to its high potential toxicity and *** study aimed to reveal the risk of Cd accumulation in soil and wheat/maize systems,with a specific focus on the source-specific ecological risk,human health risk and Cd enrichment *** this we investigated more than 6100 paired soil and grain samples with 216 datasets including soil Cd contents,soil ph and grain Cd contents of 85 sites from *** results showed that mining activities,sewage irrigation,industrial activities and agricultural practices were the critical factors causing Cd accumulation in wheat and maize cultivated ***,mining activities contributed to a higher Cd accumulation risk in the southwest China and Middle Yellow River regions;sewage irrigation influenced the Cd accumulation in the North China *** addition,the investigated sites were classified into different categories by comparing their soil and grain Cd contents with the Chinese soil screening values and food safety values,*** enrichment models were developed to predict the Cd levels in wheat and maize *** results showed that the models exhibited a good performance for predicting the grain Cd contents among safe and warning sites of wheat (R2=0.61 and 0.72,respectively);while the well-fitted model for maize was prone to the overestimated sites (R2=0.77).This study will provide national viewpoints for the risk assessments and prediction of Cd accumulation in soil and wheat/maize systems.

关键词： Ecological risk Enrichment models Cadmium health risk assessment Pollution sources

Pressure induced stability: from pneumatic structures to Tensairity~

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Journal of Bionic Engineering 2004年第3期1卷 141-148页

作者： Rolf h. Luchsinger Mauro Pedretti andreas Reinhard Prospective Concepts ag Flughofstrasse 41 8152 Glattbrugg SwitzerlandAirlight Ltd. Via Croce 1 6710 Biasca Switzerland Prospective Concepts ag Flughofstrasse 41 8152 Glattbrugg Switzerland

Structural stabilization by a pressurized fluid is very common in nature, however hardly found in technology. Car tires, hot air balloons, airships and airhouses are among the few technical exceptions, which are stabilized by a compressed medium, typically air. Restricted by simple geometries and a very limited load bearing capacity these pneumatic structures could succeed only in very specialized applications. Nevertheless, prospective concepts ag has systematically investigated pneumatic structures during the last few years. As a major result, it was demonstrated that almost any shape can be made with pneumatic structures and that astonishing structures such as the pneumatic airplane Stingray can be realized even with low air pressure. On top of that, Airlight Ltd. in close collaboration with prospective concepts ag has recently developed the fundamental new structural concept Tensairity. The synergetic combination of an inflated structure with conventional structural elements such as cables and struts yields pneumatic light-weight structures with the load bearing capacity of steel girders. Thus, complex forms and high strength open up many new opportunities for pressure induced stability in technology. An overview of these recent developments is presented and the close relationship of pneumatic structures with biology is outlined.

关键词： pneumatic structures tensairity web technology aviation self-repairing membrane

Achieving single-lobed far-field patterns of broad area laser diode with external cavity feedback

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Chinese Optics Letters 2003年第6期1卷 334-336页

作者：葛剑虹陈军 andreas hermerschmidt h.J.Eichler The State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 Optisches Institut Technische Univeisitat Berlin StraBe des 17. Juni 135 10623 Berlin Germany

We demonstrate a technique for single transverse mode operation of high-power broad area laser diode (BAL). In the experiment, the hR mirror is used as an external cavity mirror and the grating is used as a wavelength selective component. By tiling the hR mirror and the grating, the number of transverse modes oscillating in the cavity can be limited and the spectral bandwidth of the laser diode can be reduced. A single-lobed near diffraction-limited laser beam with the beam divergence (FWhM) of 0.43°, the spectral line-width of 0.7 nm and the output power of 350 mW are obtained. With the feedback, the power density of the output laser beam is increased 6 times in comparison with the free running.

关键词： Cavity resonators Diffraction gratings high power lasers Mirrors

Automatic identification of crystal structures and interfaces via artificial-intelligence-based electron microscopy

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npj Computational Materials 2023年第1期9卷 489-499页

作者： andreas Leitherer Byung Chul Yeo Christian h.Liebscher Luca M.Ghiringhelli The NOMAD Laboratory at the Fritz-haber-Institut of the Max-Planck-Gesellschaft and IRIS-Adlershof of the humboldt-Universität zu Berlin BerlinGermany Department of Energy Resources Engineering Pukyong National UniversityBusan 48513Republic of Korea Max-Planck-Institut für Eisenforschung 40237 DüsseldorfGermany Physics Department and IRIS Adlershof Humboldt-Universität zu BerlinBerlinGermany Present address:Department of Materials Science and Engineering Friedrich-Alexander Universität Erlangen-NürnbergErlangenGermany

Characterizing crystal structures and interfaces down to the atomic level is an important step for designing advanced *** electron microscopy routinely achieves atomic resolution and is capable to resolve complex arrangements of atoms with picometer ***,we present AI-STEM,an automatic,artificial-intelligence based method,for accurately identifying key characteristics from atomic-resolution scanning transmission electron microscopy(STEM)images of polycrystalline *** method is based on a Bayesian convolutional neural network(BNN)that is trained only on simulated ***-STEM automatically and accurately identifies crystal structure,lattice orientation,and location of interface regions in synthetic and experimental *** model is trained on cubic and hexagonal crystal structures,yielding classifications and uncertainty estimates,while no explicit information on structural patterns at the interfaces is included during *** work combines principles from probabilistic modeling,deep learning,and information theory,enabling automatic analysis of experimental,atomic-resolution images.

关键词： materials crystal estimates

Anxiety and depression in adult patients with celiac disease on a gluten-free diet

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World Journal of Gastroenterology 2010年第22期16卷 2780-2787页

作者： Winfried huser Karl-heinz Janke Bodo Klump Michael Gregor andreas hinz Department of Internal Medicine I Klinikum Saarbrücken Winterberg 1 D-66119 Saarbrücken and Department of Psychosomatic Medicine and Psychotherapie Technische Universitt München Baden-Württemberg State health Office District Government Stuttgart Gastroenterology and Gastrointestinal Cancer St. Anna Hospital Obere Waiblinger Starβe 101 D-70374 Stuttgart Germany and Department of Internal Medicine 1 Universittskliniken Tübingen Department of Internal Medicine 1 Universittskliniken Tübingen Department of Medical Psychology and Medical Sociology Universitt Leipzig

AIM: To compare anxiety and depression levels in adult patients with celiac disease (CD) on a gluten-free diet (GFD) with ***: The levels of anxiety, depression and of a probable anxiety or depressive disorder were assessed by the hospital Anxiety and Depression Scale in 441 adult patients with CD recruited by the German Celiac Society, in 235 age-and sex-matched patients with inflammatory bowel disease (IBD) in remission or with slight disease activity, and in 441 adult persons of a representative German general population sample (GP). Potential demographic (age, sex, social class, family status) and disease-related (latency to diagnosis, duration of GFD, compliance with GFD, thyroid disease) predictors of anxiety and depression in CD were tested for by regression analyses. RESULTS: The level of anxiety in CD patients was predicted (R 2 = 0.07) by female gender (P = 0.01). Female sex (OR = 3.6, 95% CI: 1.3-9.4, P = 0.01) was associated with a probable anxiety disorder. Living alone (OR = 0.5, 95% CI: 0.2-0.9, P = 0.05) was associated with a reduced risk of an anxiety disorder. The level of depression and a probable depressive disorder were not predicted by any of the demographic and medical variables tested for. The levels of anxiety in patients with CD (6.6 ± 3.4) and with IBD (6.9 ± 3.7) were higher than those of persons in the GP (4.6 ± 3.3) (both P he levels of depression in persons with CD (4.2 ± 3.4), IBD (4.6 ± 3.4) and of the GP (4.2 ± 3.8) did not differ (P = 0.3). The prevalence of a probable anxiety disorder in persons with CD (16.8%) and IBD (14.0%) was higher than that of the GP (5.7%) (P he prevalence of a probable depressive disorder did not differ significantly between the three groups (P = 0.1). CONCLUSION: Anxiety in adult German female celiacs on a GFD is higher than in persons of the GP. Female celiacs on a GFD should be screened for anxiety.

关键词： Celiac disease Anxiety Depression Gender