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Neural Regeneration Research 2024年第11期19卷 2343-2344页

作者： Gefei Chen Jan johansson Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Department of Cell and Molecular Biology Uppsala UniversityUppsalaSweden

Alzheimer’s disease(AD)is the most prevalent form of dementia,i.e.,progressive memory loss and profound cognitive dysfunction,resulting in a considerable societal *** the neuropathological level,the brains of AD patients exhibit amyloid-β(Aβ)plaques,neurofibrillary tangles,and neuroinflammation(Sala Frigerio and De Strooper,2016).

关键词： Alzheimer inflammation Aβ

Mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus johansson P.MARKLUND M.BJORLING Y.SHI Division of Machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. Moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. Moreover, a loosely adhered tribofilm was observed on top of the CF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere

Integration of multiple flexible electrodes for realtime detection of barrier formation with spatial resolution in a gut-on-chip system

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Microsystems & Nanoengineering 2024年第1期10卷 105-114页

作者： Mara Lucchetti Gabriel Werr Sofia johansson Laurent Barbe Léa Grandmougin Paul Wilmes Maria Tenje Luxembourg Centre for Systems Biomedicine(LCSB) University of LuxembourgEsch-sur-Alzette L-4362Luxembourg Division of Biomedical Engineering Department of Materials Science and EngineeringScience for Life LaboratoryUppsala University75121 UppsalaSweden Department of Life Sciences and Medicine Faculty of ScienceTechnology and MedicineUniversity of LuxembourgEsch-sur-Alzette L-4362Luxembourg

In healthy individuals,the intestinal epithelium forms a tight barrier to prevent gut bacteria from reaching blood *** study the effect of probiotics,dietary compounds and drugs on gut barrier formation and disruption,human gut epithelial and bacterial cells can be cocultured in an in vitro model called the human microbial crosstalk(HuMiX)gut-on-a-chip ***,we present the design,fabrication and integration of thin-film electrodes into the HuMiX platform to measure transepithelial electrical resistance(TEER)as a direct readout on barrier tightness in *** various aspects of the HuMiX platform have already been set in their design,such as multiple compressible layers,uneven surfaces and nontransparent materials,a novel fabrication method was developed whereby thin-film metal electrodes were first deposited on flexible substrates and sequentially integrated with the HuMiX system via a transfer-tape ***,to measure localized TEER along the cell culture chamber,we integrated multiple electrodes that were connected to an impedance analyzer via a *** further developed a dynamic normalization method because the active measurement area depends on the measured TEER *** fabrication process and system setup can be applicable to other barrier-on-chip *** a proof-of-concept,we measured the barrier formation of a cancerous Caco-2 cell line in real-time,which was mapped at four spatially separated positions along the HuMiX culture area.

关键词： barrier system multiple

HLLBY与SDVA E两座土石坝采用电阻监测法探测内部侵蚀

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HLLBY与SDVA E两座土石坝采用电阻监测法探测内部侵蚀

An overview of cryptographic primitives for possible use in 5G and beyond

大坝安全与堤坝隐患探测国际学术研讨会

作者： Torleif Dahlin Pontus Sjdahl sam johansson Lund大学 Lund大学 sam johansson AB水研究

对瑞典的几座大坝采用长期电阻监测,进行渗流测量和确定病险位置。基本原理为温度的季节性变化和所有溶解的固体,它们导致了随大坝季节性电阻变化而变化的渗流。这种变化可以使用高性能监测系统测量,该系统由Lund大学开发。用这种方法... 详细信息

对瑞典的几座大坝采用长期电阻监测,进行渗流测量和确定病险位置。基本原理为温度的季节性变化和所有溶解的固体,它们导致了随大坝季节性电阻变化而变化的渗流。这种变化可以使用高性能监测系统测量,该系统由Lund大学开发。用这种方法进行的测量始于1994年, 1996年进行了第一次永久安装。除了几次短暂中断,到2005年为止,每天都能获取数据。这些数据独特地、清楚地显示了季节变化。对瑞典两座土石坝的长期监测经验说明可以探测渗流的不规则性。渗流率在顺利的情况下可量化,内部侵蚀过程的迹象也已经探测到。

关键词：电阻渗流探测内部侵蚀堤坝

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Science China(Information Sciences) 2020年第12期63卷 5-26页

作者： Jing YANG Thomas johansson Department of Electrical and Information Technology Lund University

This survey overviews the potential use of cryptographic primitives in the fifth-generation mobile communications system(aka 5G) and beyond. It discusses the new security challenges that come with 5G and presents the upcoming security architecture. It shows the use of current cryptographic algorithms and discusses new algorithms or modifications of existing ones, that can be relevant. It also discusses the need for lightweight algorithms to meet the new use cases as well as the general demand for algorithms secure even when large quantum computers are available.

关键词： 5G cryptographic primitives lightweight cryptography post-quantum cryptography

A site dependent top height growth model for hybrid aspen

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Journal of Forestry Research 2013年第4期24卷 691-698页

作者： Tord johansson Department of Energy and Technology Swedish University of Agricul- tural Sciences

In this study height growth models for hybrid aspen were developed using three growth equations. The mean age of the hybrid aspen was 21 years （range 15-51 years） with a mean stand density of 946 stems ha-~ （87-2374） and a mean diameter at breast height （over bark） of 19.6 cm （8.5-40.8 cm）. Site index was also examined in relation to soil type. Multiple samples were collected for three types of soil： light clay, medium clay and till. Site index curves were constructed using the col- lected data and compared with published reports. A number of dynamic equations were assessed for modeling top-height growth from total age.

关键词： top height farmland hybrid aspen site index soil types stands total age soil type

Biomass production of hybrid aspen growing on former farm land in Sweden

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Journal of Forestry Research 2013年第2期24卷 237-246页

作者： Tord johansson Department of Energy and Technology Swedish University of Agricultural Sciences

We construct dry weight equations for hybrid aspen growing on former farmland in Sweden. Dry weight equations for fractions of hybrid aspen trees were also made. We estimated biomass production in 24 stands. The stands were located in Sweden at latitudes ranging from 55 to 60o N. The mean age was 18 years （range 15-23）, the mean stand density 1090 stems·ha-1 （range 378 2374）, and the mean diameter at breast height （over bark） 178 mm （range 85 244 mm）. Soil types in the hybrid aspen stands were mainly clay （21 stands）, tills （2 stands） and other （1 stand）. The mean total standing dry weight above stump level （≈ 200 mm） for the hybrid aspen stands was 135±53 t·ha-1 with a range of 42 219 t·ha-1 . In addition to estimating conventional dry weights of trees and tree components, basic density, specific leaf area （SLA）, projected leaf area （PLA） and leaf area index （LAI） were estimated and were in agreement with published figures.

关键词： basic density biomass production farmland hybrid aspen MAI plantation forestry

Misconceptions in global reactions and formula writing

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Defence Technology（防务技术） 2016年第5期12卷 419-421页

作者： Stig R. johansson The Swedish Section for Detonics and Combustion Sweden

The frequently used concept of "global reaction" is discussed and the reason for the confusion behind explained. The misconception is cleared by formula writing based on the donor–acceptor(donac) reaction concept and... 详细信息

关键词： Global reaction Donac reactions Formula writing Pyrotechnics Chlorate manufacture

Rock mass response for lined rock caverns subjected to high internal gas pressure

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第1期15卷 119-129页

作者： Davi Rodrigues Damasceno Johan Spross Fredrik johansson Division of Soil and Rock Mechanics KTH Royal Institute of TechnologySE-10044StockholmSweden

The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude *** the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not *** and numerical models can be used to estimate the rock mass response to high internal pressure;however,the fitness of these models under different in situ stress conditions and cavern shapes has not been *** this paper,the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is *** analytical model is derived in detail and finite element(FE)models considering both two-dimensional(2D)and three-dimensional(3D)geometries are *** models are verified with field measurements from the LRC in Skallen,southwestern *** analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern *** the case of anisotropic horizontal in situ stresses,as the conditions in Skallen,the 3D FE model is the best approach.

关键词： Lined rock caverns(LRCs) High pressure Rock mass response In situ stress condition Cavern shape Gas storage