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Microsystems & Nanoengineering 2023年第4期9卷 181-195页

作者： Konstantinos Kechagidis Benjamin Owen Lionel Guillou Henry Tse Dino Di Carlo timm krüger School of Engineering Institute for Multiscale ThermofluidsUniversity of EdinburghW Mains RdEdinburgh EH93JW ScotlandUK Cytovale Inc.Executive Park Blvd.San Fransisco CA 90095 CAUSA Department of Bioengineering University of CaliforniaWestwood PlazaLos Angeles 610101 CAUSA

The study of flow and particle dynamics in microfluidic cross-slot channels is of high relevance for lab-on-a-chipapplications. In this work, we investigate the dynamics of a rigid spherical particle in a cross-slot junction for a channelheight-to-width ratio of 0.6 and at a Reynolds number of 120 for which a steady vortex exists in the junction *** an in-house immersed-boundary-lattice-Boltzmann code, we analyse the effect of the entry position of theparticle in the junction and the particle size on the dynamics and trajectory shape of the particle. We find that thedynamics of the particle depend strongly on its lateral entry position in the junction and weakly on its vertical entryposition;particles that enter close to the centre show trajectory oscillations. Larger particles have longer residencetimes in the junction and tend to oscillate less due to their confinement. Our work contributes to the understanding ofparticle dynamics in intersecting flows and enables the design of optimised geometries for cytometry and particlemanipulation.

关键词： particle dynamics spherical

Sequence diversity of hepatitis C virus: Implications for immune control and therapy

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World Journal of Gastroenterology 2007年第36期13卷 4807-4817页

作者： Joerg timm Michael Roggendorf University of Essen Instituteof Virology Essen 45122 Germany

With approximately 3% of the world’s population (170 million people) infected with the hepatitis C virus (HCV), the WHO has declared HCV a global health problem. Upon acute infection about 50%-80% of subjects develop chronic hepatitis with viral persistence being at risk to develop liver cirrhosis and hepatocellular carcinoma. One characteristic of HCV is its enormous sequence diversity, which represents a significant hurdle to the development of both effective vaccines as well as to novel therapeutic interventions. Due to a polymerase that lacks a proofreading function HCV presents with a high rate of evolution, which enables rapid adaptation to a new environment including an activated immune system upon acute infection. Similarly, novel drugs designed to specifically inhibit viral proteins will face the potential problem of rapid selection of drug resistance mutations. This review focuses on the sequence diversity of HCV, the driving forces of evolution and the impact on immune control and treatment response. An important feature of any therapeutic or prophylactic intervention will be an efficient attack of a structurally or functionally important region in the viral protein. The understanding of the driving forces, but also the limits of viral evolution, will be fundamental for the design of novel therapies.

关键词： Hepatitis C Virus Evolution Escape Drug resistance Selection

Generalized Baumslag-Solitar Graphs with Soluble Fundamental Groups

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Algebra Colloquium 2014年第1期21卷 53-58页

作者： Alberto L. Delgado Derek J.S. Robinson Mathew timm vDepartment of Mathematics illinois State University Normal IL 61790 USA Department of Mathematics University of Illinois at Urbana-Champaign Urbana IL 61801 USA Department of Mathematics Bradley University Peoria IL 61625 USA

It is shown that the generalized Baumslag-Solitar graphs which have soluble fundamental groups can be constructed from four simple types of graph by a process of decoration. The method of proof is elementary and emplo... 详细信息

关键词： generalized Baumslag-Solitar graph soluble fundamental group

Perioperative treatment options in resectable pancreatic cancer-how to improve long-term survival

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World Journal of Gastrointestinal Oncology 2016年第3期8卷 248-257页

作者： Marianne Sinn Marcus Bahra timm Denecke Sue Travis Uwe Pelzer Hanno Riess Department of Medical Oncology and Haematology Charité-Universitatsmedizin Berlin Department of General Visceral and Transplantation SurgeryCharité-Universitatsmedizin Berlin Institute of Radiology Charité-Universitatsmedizin Berlin

Surgery remains the only chance of cure for pancreatic cancer, but only 15%-25% of patients present with resectable disease at the time of primary diagnosis. Important goals in clinical research must therefore be to allow early detection with suitable diagnostic procedures, to further broaden operation techniques and to determine the most effective perioperative treatment of either chemotherapy and/or radiation therapy. More extensive operations involving extended pancreatectomy, portal vein resection and pancreatic resection in resectable pancreatic cancer with limited liver metastasis, performed in specialized centers seem to be the surgical procedures with a possible impact on survival. After many years of stagnation in pharmacological clinical research on advanced pancreatic ductal adenocarcinomas(PDAC)- since the approval of gemcitabine in 1997- more effective cytotoxic substances(nab-paclitaxel) and combinations(FOLFIRINOX) are now available for perioperative treatment. Additionally, therapies with a broader mechanism of action are emerging(stroma depletion, immunotherapy, antiinflammation), raising hopes for more effective adjuvant and neoadjuvant treatment concepts, especially in the context of "borderline resectability". Only multidisciplinary approaches including radiology, surgery, medical and radiation oncology as the backbones of the treatment of potentially resectable PDAC may be able to further improve the rate of cure in the future.

关键词： Pancreatic cancer Perioperative treatment Perioperative radiology Chemotherapy

Synchrotron microtomography reveals insights into the degradation kinetics of bio-degradable coronary magnesium scaffolds

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Bioactive Materials 2024年第2期32卷 1-11页

作者： Roman Menze Bernhard Hesse Maciej Kusmierczuk Duote Chen timm Weitkamp Stephanie Bettink Bruno Scheller MeKo Manufacturing e.K. Im Kirchenfelde 12-1431157SarstedtGermany Xploraytion GmbH Bismarckstr.10-1210625BerlinGermany Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190Saint-AubinFrance InnoRa GmbH Robert-Koch-Platz 410115BerlinGermany Universität des Saarlandes Campus Homburg66421HomburgGermany

Bioresorbable magnesium scaffolds are a promising future treatment option for coronary artery stenosis,especially for young *** to the degradation of these scaffolds(<1 year),long-term device-related clinical events could be reduced compared to treatments with conventional drug eluting *** clinical trials indicate a return of vasomotion after one year,which may be associated with improved long-term clinical ***,even after decades of development,the degradation process,ideal degradation time and biological response in vivo are still not fully *** present study investigates the in vivo degradation of magnesium scaffolds in the coronary arteries of pigs influenced by different strut thicknesses and the presence of antiproliferative *** to high 3D image contrast of synchrotron-based micro-CT with phase contrast(SR-μCT),a qualitative and quantitative evaluation of the degradation morphology of magnesium scaffolds was *** the segmentation of theμCT images a convolutional network architecture(U-net)was exploited,demonstrating the huge potential of merging high resolution SR-μCT with deep learning(DL)supported data *** total,30 scaffolds,made of the rare earth alloy Resoloy^(®),with different strut designs were implanted into the coronary arteries of 10 domestic pigs for 28 days using drug-coated or uncoated angioplasty balloons for *** degradation morphology was analyzed using scanning electron microscopy,energy dispersive x-ray spectroscopy and SR-μ*** data from these methods were then related to data from angiography,optical coherence tomography and histology.A thinner strut size(95 vs.130μm)and the presence of paclitaxel indicated a slower degradation rate at 28 d in vivo,which positively influences the late lumen loss(0.5 and 0.6 mm vs.1.0 and 1.1 mm)and recoil values(0 and 1.7%vs.6.1 and 22%).

关键词： Resoloy Magnesium scaffold DCB Paclitaxel Degradation Inflammation Artificial intelligence

High resolution scanning gate microscopy measurements on InAs/GaSb nanowire Esaki diode devices

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Nano Research 2014年第6期7卷 877-887页

作者： James L. Webb Olof Perssor Kimberly A. Dick Claes Thelander Rainer timm Anders Mikkelsen Division of Synchrotron Radiation Research Lund University Sweden Center forAnalysis and Synthesis Lund University Sweden Division of Solid State Physics Lund University Sweden

Gated transport measurements are the backbone of electrical characterization of nanoscale electronic devices. Scanning gate microscopy （SGM） is one such gating technique that adds crucial spatial information, accessing the localized properties of semiconductor devices. Nanowires represent a central device concept due to the potential to combine very different materials. However, SGM on semiconductor nanowires has been limited to a resolution in the 50-100 nm range. Here, we present a study by SGM of newly developed III-V semiconductor nanowire InAs/GaSb heterojunction Esaki tunnel diode devices under ultra-high vacuum. Sub-5 nm resolution is demonstrated at room temperature via use of quartz resonator atomic force microscopy sensors, with the capability to resolve InAs nanowire facets, the InAs/GaSb tunnel diode transition and nanoscale defects on the device. We demonstrate that such measurements can rapidly give important insight into the device properties via use of a simplified physical model, without the requirement for extensive calculation of the electrostatics of the system. Interestingly, by precise spatial correlation of the device electrical transport properties and surface structure we show the position and existence of a very abrupt （〈10 nm） electrical transition across the InAs/GaSb junction despite the change in material composition occurring only over 30-50 nm. The direct and simultaneous link between nanostructure composition and electrical properties helps set important limits for the precision in structural control needed to achieve desired device performance.

关键词： nanowire,scanning gate microscopy Esaki tunnel diode,InAs,GaSb,III-V,heterostructure

Perceived damage and areas of needed research for wildlife pests of California agriculture

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Integrative Zoology 2014年第3期9卷 265-279页

作者： Roger A.BALDWIN Terrell P.SALMON Robert H.SCHMIDT Robert M.timm Statewide IPM Program University of California Cooperative ExtensionParlierCAUSA University of California Cooperative Extension San DiegoCAUSA Department of Environment and Society Utah State UniversityLoganUTUSA Hopland Research and Extension Center University of CaliformniaHoplandCAUSA

Many wildife species cause extensive damage to a variety of agricultural commodities in California,with es-timates of damage in the hundreds of millions *** the limited availability of resources to solve all human-wildlife conficts,we should focus management efforts on issues that provide the greatest benefit to ag-ricultural commodities in *** survey provides quantitative data on research needs to better guide future efforts in developing more effective,practical and appropriate methods for managing these *** found that ground squirels,pocket gophers,birds,wild pigs,coyotes and voles were the most common agricul-tural wildlife pest species in *** damage caused by these species could be quite high,but varied by agricultural *** most species,common forms of damage included loss of crop production and di-rect death of the plant,although livestock depredation was the greatest concern for *** methods used most frequently and those deemed most effective varied by pest species,although greater advancements in control methods were listed as a top research priority for all ***,the use of toxicants,biocon-trol and trapping were the most preferred methods for control,but this varied by *** general,integrated pest management practices were used to control wildlife pests,with a special preference for those approaches that were efficacious and quick and inexpensive to *** information and survey design should be useful in establishing research and management priorities for wildlife pest species in California and other similar re-gions.

关键词： agriculture California human-wildlife conflict integrated pest management survey

Analysis of metabolic alterations in Arabidopsis following changes in the carbon dioxide and oxygen partial pressures

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Journal of Integrative Plant Biology 2014年第9期56卷 941-959页

作者： Alexandra Florian Stefan timm Zoran Nikoloski Takayuki Tohge Hermann Bauwe Wagner L.Araujo Alisdair R.Fernie Max Planck Institute for Molecular Plant Physiology Department of Plant Physiology University of Rostock Max-Planck Partner group at the Departament of Plant Biology Federal University of Vicosa

As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the *** the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas ***,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in ***,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains *** address these questions,plants Arabidopsis thaliana（Arabidopsis） ecotype Columbia（Col-O） grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this *** results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite *** results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription.

关键词： Carbon dioxide partial pressures gene expression metabolic profiling oxygen partial pressures

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Wheelchair Seating: Peak Pressure Distribution in Young versus Elderly Healthy Controls

2012年

作者： (德) Angelika Becker-Kavan Jeffrey Lloyd Jochen timm

本书以四位职员的有趣故事为线索贯穿于10个单元。第一单元是启蒙动力期, 帮助学生迈入英语学习的第一步。在其他单元中精选案例教学, 寓教于乐, 将工作和社会交际轻松相结合, 教会学生使用恰当的专业技术语言。每个单元包含语言部分、... 详细信息

ISBN: (纸本)9787894335951;9787111391616

本书以四位职员的有趣故事为线索贯穿于10个单元。第一单元是启蒙动力期, 帮助学生迈入英语学习的第一步。在其他单元中精选案例教学, 寓教于乐, 将工作和社会交际轻松相结合, 教会学生使用恰当的专业技术语言。每个单元包含语言部分、网络资源、词汇部分、语法部分和学习建议五个部分。

关键词：机械工程

来源：畅想之星图书光盘版（南... 评论

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Open Journal of Therapy and Rehabilitation 2019年第2期7卷 25-34页

作者： Marina timm Kersti Samuelsson Center of Assistive Devices County Council Sk&#246 vde Sweden Department of Rehabilitation Medicine and Department of Medical and Health Sciences Link&#246 ping University Link&#246 ping Sweden

Background: People may use a wheelchair when they need assistance with mobility. Some users have to remain seated in their wheelchair for most of their awake time and for a lot of activities. The need for a well fitted and supportive wheelchair is important and, for those who use the wheelchair for many hours, peak pressure distribution is of interest to prevent pressure ulcers and discomfort. Aim: To describe how high local peak pressures may be distributed over risk areas for pressure ulcers in different wheelchair settings. Methods: Two groups of healthy adults were recruited (40 elderly and 30 younger individuals). Two standard models of manual wheelchairs were used together with two types of wheelchair cushions. Results: The elderly group had a higher peak pressure over the ischial tuberosity and increased posterior pelvic rotation in the shaped seat cushion. Both groups had higher peak pressure over the trochanter in the shaped seat cushion. Peak pressure was also higher over the coccyx for the elderly in the shaped seat cushion compared with the plain cushion;this was lower for the younger group. Discussion: The results indicate that age might influence the important physical prerequisites when fitting a wheelchair to an individual.

关键词： Age Interface Pressure Pressure Ulcers Prevention