检索结果-南通市图书馆

Modeling and measuring glucose diffusion and consumption by colorectal cancer spheroids in hanging drops using integrated biosensors

引用

Microsystems & Nanoengineering 2022年第1期8卷 193-210页

作者： Nassim Rousset Rubén López sandoval Mario Matteo Modena andreas Hierlemann Patrick M.Misun ETH Zürich Department of Biosystems Science and EngineeringBio Engineering LaboratoryMattenstrasse 26CH-4058 BaselSwitzerland

As 3D in vitro tissue models become more pervasive,their built-in nutrient,metabolite,compound,and waste gradients increase biological relevance at the cost of analysis *** these gradients and the resulting metabolic heterogeneity requires invasive and time-consuming *** alternative is using electrochemical biosensors and measuring concentrations around the tissue model to obtain size-dependent metabolism *** our hanging-dropintegrated enzymatic glucose biosensors,we conducted current measurements within hanging-drop compartments hosting spheroids formed from the human colorectal carcinoma cell line *** developed a physics-based mathematical model of analyte consumption and transport,considering(1)diffusion and enzymatic conversion of glucose to form hydrogen peroxide(H_(2)O_(2))by the glucose-oxidase-based hydrogel functionalization of our biosensors at the microscale;(2)H_(2)O_(2)oxidation at the electrode surface,leading to amperometric H_(2)O_(2)readout;(3)glucose diffusion and glucose consumption by cancer cells in a spherical tissue model at the microscale;(4)glucose and H_(2)O_(2)transport in our hangingdrop compartments at the macroscale;and(5)solvent evaporation,leading to glucose and H_(2)O_(2)*** model relates the measured currents to the glucose concentrations generating the *** low limit of detection of our biosensors(0.4±0.1μM),combined with our current-fitting method,enabled us to reveal glucose dynamics within our *** measuring glucose dynamics in hanging-drop compartments populated by cancer spheroids of various sizes,we could infer glucose distributions within the spheroid,which will help translate in vitro 3D tissue model results to in vivo.

关键词： diffusion hanging simplicity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy transition toward carbon-neutrality in China:Pathways,implications and uncertainties

引用

Frontiers of Engineering Management 2022年第3期9卷 358-372页

作者： Yong YANG Hui WANG andreas LOsCHEL Peng ZHOU College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China school of Economics and Management China Universityof Petroleum(East China)Qingdao 266580China Ruhr-Universitat Bochum 44801 BochumGermany

Achieving carbon neutrality in China before 2060 requires a radical energy *** identify the possible transition pathways of China's energy system,this study presents a scenario-based assessment using the Low Emissions Analysis Platform(LEAP)*** could peak the carbon dioxide(CO_(2))emissions before 2030 with current policies,while carbon neutrality entails a reduction of 7.8 Gt CO_(2)in emissions in 2060 and requires an energy system *** assessment of the relationship between the energy transition and energy return on investment(EROI)reveals that energy transition may decrease the EROI,which would trigger increased energy investment,energy demand,and *** analysis further shows that the slow renewable energy integration policies and carbon capture and storage(CCs)penetration pace could hinder the emission mitigation,and the possible fossil fuel shortage calls for a much rapid proliferation of wind and solar *** suggest a continuation of the current preferential policies for renewables and further research and development on deployment of *** results also indicate the need for backup capacities to enhance the energy security during the transition.

关键词： scarbon neutrality energy transition uncertainty EROI LEAP

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

simultaneous multiple time scale imaging for kHz-MHz high-speed accelerometry

引用

Photonics Research 2022年第7期10卷 1712-1722页

作者： VAssILY KORNIENKO DAVID ANDERssON MEHDI sTITI JONAs RAVELID sIMON EK andreas EHN EDOUARD BERROCAL ELIAs KRIsTENssON Division of Combustion Physics Department of PhysicsLund UniversityLundSweden

Fast transient events,such as the disintegration of liquid bodies or chemical reactions between radical species,involve various processes that may occur at different time ***,there are two alternatives for monitoring such events:burst-or high-speed *** imaging at ultrahigh speeds(~100 MHz to THz)allows for the capture of nature's fastest processes but only for a narrowly confined period of time and at a repetition rate of~10 *** long lasting,rapidly evolving transient events requires a significantly higher repetition rate,which is met by existing~kHz to 1 MHz high-speed imaging ***,the use of such systems eliminates the possibility to observe dynamics occurring on the sub-microsecond time *** this paper,we present a solution to this technological gap by combining multiplexed imaging with high-speed sensor technology,resulting in temporally resolved,high-spatial-resolution image series at two simultaneous time *** further demonstrate how the collection of such data opens up the tracking of rapidly evolving structures up to MHz burst rates over long durations,allowing,for the first time,to our knowledge,the extraction of acceleration fields acting upon the liquid bodies of an atomizing spray in two dimensions at k Hz frame rates.

关键词： repetition high transient

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cellular polyploidy in organ homeostasis and regeneration

引用

蛋白质与细胞:英文版 2023年第8期14卷 560-578页

作者： Juntao Fang Alain de Bruin andreas Villunger Raymond schiffelers Zhiyong Lei Joost P.G.sluijter Department of Experimental Cardiology University Medical Center UtrechtHeidelberglaan 1003584 CX UtrechtThe Netherlands Department of Pediatrics University of GroningenPO Box 30.0019700 RB GroningenThe Netherlands Department of Pathobiology Dutch Molecular Pathology CenterUtrecht UniversityYalelaan13584 CL UtrechtThe Netherlands Institute for Developmental Immunology BiocenterMedical University of InnsbruckInnrain 806020 InnsbruckAustria Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases Lazarettgasse 14AKH BT 25.3 c/o CeMM Research BuildingHaupteingang Level 11090 WienOsterreich CeMM Research Center for Molecular Medicine of the Austrian Academy of sciences Lazarettgasse 14AKH BT 25.3A-1090 ViennaAustria CDL Research University Medical Center UtrechtHeidelberglaan 1003584 CX UtrechtThe Netherlands

Polyploid cells,which contain more than one set of chromosome pairs,are very common in *** can provide cells with several potential benefits over their diploid counterparts,including an increase in cell size,contributing to organ growth and tissue homeostasis,and improving cellular robustness via increased tolerance to genomic stress and apoptotic ***,we focus on why polyploidy in the cell occurs and which stress responses and molecular signals trigger cells to become ***,we discuss its crucial roles in cell growth and tissue regeneration in the heart,liver,and other tissues.

关键词： cellular polyploidy tissue regeneration cardiac regeneration liver regeneration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Exploring the degradation behavior of MgXAg alloys by in vitro electrochemical methods

引用

Bioactive Materials 2022年第1期7卷 441-452页

作者： Yuqiuhan Zhang Tycho Zimmermann Wolf-Dieter Mueller Frank Witte Florian Beuer andreas schwitalla Charit´e-Universit¨atsmedizin Berlin corporate member of Freie Universit¨at Berlin and Humboldt-Universit¨at zu BerlinDental Materials and Biomaterial ResearchDepartment of ProsthodonticsGeriatric Dentistry and Craniomandibular DisordersAßmannshauser Str.4-614197BerlinGermany

Magnesium as biodegradable biomaterial could serve as bone augmentation material in implant *** knowledge about the predictability of the biodegradation process is essential as this process needs to go hand in hand with the formation of new bone to gradually replace the augmentation ***,this work aimed to assess if the electrochemistry(EC)measurements of the corrosion process correlate with the surface features at various time points during the surface degradation,in order to describe the degradation process of Mg and Mg alloys more reliably,under the assumption that differences in EC behavior can be detected and related to specific patterns on the *** this test setup,a special optical chamber was used for electrochemical measurements on Mg and Mg-alloys(Mg2Ag,Mg4Ag,and Mg6Ag).specimens were investigated using different circulating cell culture solutions as electrolytes,these were minimum essential medium(MEM),Hank’s Balanced salt solution(HBss),and MEM+(MEM with added sodium hydrogen carbonate)at 37℃.Open circuit potential measurements(OCP)over 30 min followed by cyclic polarization were *** electrochemistry data,including OCP,exchange current density and corrosion potential,were compared with visible changes at the surface during these treatments over *** results show that the addition of silver(Ag)leads to a“standardization”of the degradation regardless of the selected test *** is currently difficult to correlate the visible microscopic changes with the data taken from the ***,further investigations are necessary.

关键词： Biodegradable magnesium Magnesium silver alloys Electrochemistry Hydrogen evolution

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Interaction between an Accelerated Mass in straight Motion and a Hidden Energy Reservoir as a strict Mathematical Consequence of special Relativity

引用

Journal of Modern Physics 2022年第1期13卷 16-33页

作者： andreas Trupp Fachhochschule Muenster (University of Applied science) Muenster Germany

A. Einstein and H.A. Lorentz had found that the mass of an accelerated body traveling at relativistic velocity appears to depend on whether the acceleration is performed in the direction of motion or in a transverse direction. E.P. Epstein rejected this result in the “Annalen der Physik”;he rather postulated an additional force that turns up when the body is accelerated in the longitudinal direction. It can be shown that the concept of an increased longitudinal mass is based on a simple mathematical error. When correcting this error, it turns out that Epstein’s additional, hidden force is indispensable in order to avoid an inner inconsistency of special Relativity. It does most of the total work absorbed by the moving object, and is thus responsible for most of the increase in its energy (=mass), given the speed attained is relativistic. In other words: While the total force on the body needed to maintain a constant acceleration asub>0sub> is “(1-v2/c2)-1ma0=m0(1-v2/c2)-3/2a0”, the technical force needed to maintain that acceleration amounts only to “masub>0sub>=msub>0sub>(1 - vsup>2sup>/csup>2sup>)sup>-1/2sup>asub>0sub>”. The total energy of two objects that undergo a symmetrical, elastic head-on collision is therefore not conserved during the collision, thus requiring the involvement of a hidden reservoir of energy. This result is confirmed by calculations that use the concept of momenergy. The phenomenon of an apparent disappearance of energy has been noticed in particle physics already (target-experiment), but its consequences have been ignored. Instead, an explanation has been given (reduced “energy of the center of mass”) which is inconsistent

关键词： special Relativity Longitudinal Mass Transverse Mass Momenergy Target Experiment Energy of the Center of Mass Dark Energy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pt/TiO_(2–x) nanofibrous aerogel for effective nitrogen reduction: A simple strategy for simultaneous Pt formation and TiO_(2–x) vacancy engineering

引用

Chinese Chemical Letters 2022年第2期33卷 1001-1005页

作者： Meng Zhang Jin Dai shengmei Huang Dan Fang Yitao Liu Jianyong Yu Bin Ding andreas Greiner Innovation Center for Textile science and Technology College of TextilesDonghua UniversityShanghai 201620China Macromolecular Chemistry and Bavarian Polymer Institute University of BayreuthBayreuth 95440Germany

Electrocatalysis plays an increasingly important role in converting atmospheric molecules(e.g.,N_(2),CO_(2) and H_(2)O)to value-added products(e.g.,NH_(3),C_(2)H_(4)and H_(2)).However,developing a simple strategy for preparing catalysts with high performance for the effective conversion of clean energy is still full of ***,we describe a straightforward,one-step reduction method to achieve the formation of Pt nanoparticles(NPs)and the vacancy engineering of TiO_(2-x)nanofibers(NFs)simultaneously,which can be accomplished in 5 ***,a Pt/TiO_(2-x)nanofibrous aerogel(NA)with an ordered cellular archi-tecture is prepared through a directional freezing *** Pt/TiO_(2-x)NA with excellent mechanical properties can be made into a self-supporting electrode for electrocatalytic N_(2)reduction reaction(NRR),showing high NH_(3) yield rate(4.81×10^(-10)mol/s cm^(-2))and Faraday efficiency(14.9%)at-0.35 V ***.

关键词： Vacancy engineering Pt nanoparticles TiO_(2–x)nanofibers Nanofibrous aerogel Electrocatalysis Nitrogen reduction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

structural and microstructural description of relaxor-ferroelectric transition in quenched Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3)

引用

Journal of Materiomics 2022年第4期8卷 823-832页

作者： andreas Wohninsland Ann-Katrin Fetzer Rachel Broughton Jacob L.Jones K.V.Lalitha Department of Materials-and Geosciences Technical University of Darmstadt64287DarmstadtGermany Department of Materials science and Engineering North Carolina State UniversityRaleighNC27695USA

Quenching lead-free Na_(1/2)Bi_(1/2)TiO_(3)-based ceramics from sintering temperature is established to increasethe depolarization temperature,Td and the lattice *** situ synchrotron X-ray diffractionmeasurements were carried out on furnace cooled and quenched Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3)(NBT-BT)with 6and 9 mol.%BT to discern the field-induced ferroelectric *** fractions were determined fromfull pattern Rietveld refinements and utilized together with the change in unit cell volume to calculatevolumetric strain resulting from phase ***-6BT demonstrates a cubic symmetry in thefurnace cooled state but quenching stabilizes the rhombohedral R3c phase and delays the formation of afield-induced,long range-ordered tetragonal phase,thereby shifting the onset of macroscopic strain tohigher fields.A field-induced phase transition from a weakly distorted rhombohedral to tetragonal phasecan be observed in furnace cooled ***,this phase transition cannot be detected inquenched NBT-9BT,since the ferroelectric tetragonal P4mm phase is stabilized in the initial *** to the furnace cooled materials,both the quenched compositions exhibit overall negligiblevolumetric strain as a function of electric ***,scanning electron micrographs of chemi-cally etched,poled and unpoled samples reveal an increased lamellar domain contrast in the *** these findings strengthen the hypothesis of a stabilized ferroelectric order resulting in theabsence of a field-induced phase transformation in quenched NBT-BT.

关键词： Lead-free Quenching Na_(1/2)Bi_(1/2)TiO_(3)-BaTiO_(3) synchrotron diffraction Ferroelectric

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Quasi-optimal control of a solar thermal system via neural networks✩

引用

能源与人工智能(英文) 2023年第2期12卷 128-144页

作者： Jana Friese Niklas Brandt andreas schulte Christian Kirches Wilhelm Tegethoff Jürgen Köhler Technische Universität Braunschweig Institut für ThermodynamikHans–Sommer–Straße 538106 BraunschweigGermany Technische Universität Braunschweig Institut für Mathematische OptimierungUniversitätsplatz 238106 BraunschweigGermany

The optimal control of complex thermal energy systems is a challenge due to their dynamic behavior andconstantly changing boundary conditions. To maximize the energy efficiency of such a dynamic system, optimaltrajectories for the controlled variables are needed. Extensive system knowledge is required to model the systemaccurately enough to be able to compute optimal trajectories. The high computational cost of computingoptimal control solutions with traditional approaches, especially with changing boundary conditions, oftenmakes this approach unusable for applications with limited computational power, such as real-time applicationson electronic control units (ECUs). This study investigates a possible solution to this challenge using a simplifiedexample system. Optimal control solutions for different boundary and initial conditions are generated forthe selected solar thermal system using a direct multiple shooting algorithm. Based on Bellman’s optimalityprinciple, the generated solutions are transformed into a data set of optimal state–action pairs. On this basis,different types of neural networks are trained, specifically a feed-forward, a recurrent, and a radial basisfunction network. Thus, data generation and training can be performed offline, and the required online computations are significantly reduced since the evaluation of a trained neural network requires comparatively lowcentral processing unit (CPU) power. The trained neural network controllers are tested for their ability to outputnear-optimal control actions based on the current system state. The feed-forward and recurrent neural networksshow promising initial results in this regard. Open questions and the need for improvements are discussed.

关键词： Optimal control Neural networks Bellmann equation Thermal systems Optimization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

引用

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

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：