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Toward implantable devices for angle-sensitive,lens-less,multifluorescent,single-photon lifetime imaging in the brain using Fabry-Perot and absorptive color filters

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Light(Science & Applications) 2022年第2期11卷 197-211页

作者： Adriaan.j.Taal Changhyuk Lee jaebin Choi björn Hellenkamp Kenneth L.Shepard Columbia University-Department of Electrical Engineering 500W.120th St.Mudd 1310New York 10027 NYUSA Korea Institute of Science and Technology-Brain Science Institute 5 Hwarang-ro 14-gilSeongbuk-guSeoul 02792Republic of Korea

Implantable image sensors have the potential to revolutionize *** to their small form factor requirements;however,conventional filters and optics cannot be *** limitations obstruct highresolution imaging of large neural *** advances in angle-sensitive image sensors and single-photon avalanche diodes have provided a path toward ultrathin lens-less fluorescence imaging,enabling plenoptic sensing by extending sensing capabilities to include photon arrival time and incident angle,thereby providing the opportunity for separability of fluorescence point sources within the context of light-field microscopy(LFM).However,the addition of spectral sensitivity to angle-sensitive LFM reduces imager resolution because each wavelength requires a separate pixel ***,we present a 1024-pixel,50μm thick implantable shank-based neural imager with color-filtergrating-based angle-sensitive *** angular-spectral sensitive front end combines a metal–insulator–metal(MIM)Fabry–Perot color filter and diffractive optics to produce the measurement of orthogonal light-field information from two distinct colors within a single *** result is the ability to add independent color sensing to LFM while doubling the effective pixel *** implantable imager combines angular-spectral and temporal information to demix and localize multispectral fluorescent *** this initial prototype,this is demonstrated with 45μm diameter fluorescently labeled beads in scattering *** lifetime imaging is exploited to further aid source separation,in addition to detecting pH through lifetime changes in fluorescent *** these initial fluorescent targets are considerably brighter than fluorescently labeled neurons,further improvements will allow the application of these techniques to in-vivo multifluorescent structural and functional neural imaging.

关键词： filters lifetime angle

Takotsubo triggered by acute myocardial infarction：a common but overlooked syndrome？

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journal of Geriatric Cardiology 2014年第2期11卷 171-173页

作者： bj orn Redfors Wallenberg Laboratory Department of Molecular and Clinical Medicine Sahlgrenska Academy at University of Gothenburg Bruna Straket 16 413 45 Go-thenburg Sweden Department of Cardiology Sahlgrenska University Hospital Bruna Straket 16 413 45 Gothenburg Sweden

Takotsubo cardiomyopathy （TCM） is an acute cardiac syndrome characterized by extensive, but potentially reversible, left ventricular dysfunction in the absence of an explanatory coronary obstruction. Thus, TCM is distinct from coronary artery disease （CAD） and acute myocardial infarction （AMI）. However, substantial evidence for co-existing CAD in some TCM patients exist. Herein, we take this associa-tion one step further and present a case in which the patient simultaneously suffered from AMI and TCM, and in which we believe that a primary coronary event triggered TCM. An 88-year-old female presented with chest pain. Echocardiography revealed apical akinesia with hypercontractile bases. An occluded diagonal branch with suspected acute plaque rupture was identified on the angiogram, but could not explain the extent of akinesia. Cardiac function recovered completely. Thus, this patient adhered to current diagnostic criteria for TCM. TCM is a well-known complication for other conditions associated with somatic stress. It is therefore intuitive to assume that AMI, which also associates with somatic stress and elevated catecholamine, can cause TCM. Our case illustrates that TCM and AMI may occur simulta-neously. Although causality cannot be conclusively inferred from this association, the somatic stress associated with AMI may have caused TCM in this patient.

关键词： Acute myocardial infaction Catecholamine Coronary artery disease Somatic stress Takotsubo cardiomyopathy

Solanaceae pangenomes are coming of graphical age to bring heritability back

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aBIOTECH 2022年第4期3卷 233-236页

作者： björn Usadel Institute for Biological Data Science CEPLASHeinrich Heine UniversityDüsseldorfGermany IBG-4 Bioinformatics BioSCForschungszentrum JülichJülichGermany

Two recent articles describe a pangenome of potato and a graph-based pangenome for tomato,*** latter improves our understanding of the tomato genomics architecture even further and the use of this graph-based pangenom... 详细信息

关键词： Tomato Potato Pangenome Graph-based pangenome Heritability

Is a catalyst always beneficial in plasma catalysis? Insights from the many physical and chemical interactions

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journal of Energy Chemistry 2023年第10期85卷 501-533,I0013页

作者： björn Loenders Roel Michiels Annemie Bogaerts Research group PLASMAnT Department of ChemistryUniversity of AntwerpUniversiteitsplein 1B-2610 Wilrijk-AntwerpBelgium

Plasma-catalytic dry reforming of CH_(4)(DRM) is promising to convert the greenhouse gasses CH_(4) and CO_(2) into value-added chemicals, thus simultaneously providing an alternative to fossil resources as feedstock for the chemical industry. However, while many experiments have been dedicated to plasma-catalytic DRM, there is no consensus yet in literature on the optimal choice of catalyst for targeted products,because the underlying mechanisms are far from understood. Indeed, plasma catalysis is very complex,as it encompasses various chemical and physical interactions between plasma and catalyst, which depend on many parameters. This complexity hampers the comparison of experimental results from different studies, which, in our opinion, is an important bottleneck in the further development of this promising research field. Hence, in this perspective paper, we describe the important physical and chemical effects that should be accounted for when designing plasma-catalytic experiments in general, high-lighting the need for standardized experimental setups, as well as careful documentation of packing properties and reaction conditions, to further advance this research field. On the other hand, many parameters also create many windows of opportunity for further optimizing plasma-catalytic ***, various experiments also reveal the lack of improvement in plasma catalysis compared to plasma-only, specifically for DRM, but the underlying mechanisms are unclear. Therefore, we present our newly developed coupled plasma-surface kinetics model for DRM, to provide more insight in the underlying reasons. Our model illustrates that transition metal catalysts can adversely affect plasmacatalytic DRM, if radicals dominate the plasma-catalyst interactions. Thus, we demonstrate that a good understanding of the plasma-catalyst interactions is crucial to avoiding conditions at which these interactions negatively affect the results, and we provide some recommendations for im

关键词： Plasma catalysis Dry reforming of methane Discharges Reaction kinetics Modelling

This study has been supported by the Programme of Introducing Talents of Discipline to Universities(D21025),the national natural Science Foundation of China(U20B6005-05),and the national Key R&D Program of China(2019YFC0312300).

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Petroleum 2021年第4期7卷 364-384页

作者： bjørn Kvamme navid Saeidi Hyzenenergy 26701 Quail CreekLaguna HillsCA92656USA Strategic Carbon LLC 20 Ladd St.Suite 200PortsmouthNH 03801USA State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityXindu Road No.8Chengdu610500China

The global amount of energy contained in natural gas hydrates is huge,maybe as much as twice all known conventional fossil fuel *** the worldwide distribution of conventional fossil fuels,hydrocarbons trapped in water as hydrate is also available in countries with limited conventional hydrocarbon *** development towards lower global emissions of greenhouse gases requires new strategies for the use of hydrocarbons,whether they are available as conventional resources,or in the form of natural gas *** this work we outline some possible strategies of utilizing hydrocarbon energy resources in a clean and environmentally friendly *** use of carbon dioxide for producing hydrates is not *** from several experimental studies are *** this work we shed more light on thermodynamic limitations and the need for additives in order to make the approach technically *** thermodynamic analysis we show that up to 20 mol per cent n2 is feasible in a CO2/n2 injection gas based on ability to form a new hydrate with free pore water and the released enthalpy needed to dissociate in situ CH4 *** is also needed in order to keep the injection gas front free of blocking hydrate *** alcohols like methanol and ethanol have surfactant *** is demonstrated that even 10 wt%ethanol in liquid pore water still makes it feasible to create a new hydrate from injection gas containing 20 mol per cent *** of other components than CH4 in the hydrate are also *** in practical cases with a well-defined source of CO2 it is also important to investigate impact of other components like for instance H2S on the stability of injection gas hydrate,as well as changes in enthalpy of hydrate *** key element of this work is the conversion of produced hydrocarbons over to hydrogen and carbon dioxide using steam *** technology for this is very old and in daily use.

关键词： Hydrate non-equilibrium Thermodynamics Kinetics

Correlation of chromosomal polysomy with overexpression of c-myc and c-erbB-2 in primary nasopharyngeal carcinoma: Tissue microarray study

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Chinese Science Bulletin 2002年第3期47卷 217-220页

作者： Zhang, Lj Yan, j Liang, QW Huang, bj Zeng, YX Fang, Y Sun Yat Sen Univ Med Sci Canc Ctr Canc Inst Guangzhou 510060 Peoples R China

Many genes may be involved in nasopharyn-geal carcinoma (nPC) development and progression. Several known oncogenes, including c-myc and c-erb-B2, have been shown to have structural alteration and aberrant expression in nPC. Here, we constructed a tissue microarray to deter-mine the status of c-myc and c-erbB-2 oncogenes at the DnA and protein levels using interphase fluorescence in situ hy-bridization (FISH) and immunohistochemistry (IHC) and to define the diagnostic, prognostic importance of the genetic changes. Results showed that amplification of c-myc and c-erbB-2 was not found in nPC. Polysemy 8 and 17 were observed in 43%-50% and 20%-27% of nPC tumors, respectively. Overexpressions of c-myc and c-erbB-2 onco-proteins were detected in 53.6% and 54.5% cases of nPC with polysomy 8 and 17, respectively. There was no signifi-cant correlation between c-myc and c-erbB-2 staining and the clinical stage. But overexpression of c-erbB-2 was associ-ated with polysemy 17 in nPC. These findings suggest that

关键词： nasopharyngeal carcinoma c-myc c-erbB-2 tissue mi-croarray chromosomal polysomy.

Forecasting the effects of EU policy measures on the nitrate pollution of groundwater and surface waters

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journal of Environmental Sciences 2010年第6期22卷 872-877页

作者： Ralf Kunkel Peter Kreins bjrn Tetzlaff Frank Wendland Research Centre jülich Institute of Chemistry and Dynamics of the Geosphere Institute of Rural Studies Federal Agricultural Research Centre

We used the interdisciplinary model network REGFLUD to predict the actual mean nitrate concentration in percolation water at the scale of the Weser river basin （Germany） using an area differentiated （100 m × 100 m） approach. REGFLUD combines the agro-economic model RAUMIS for estimating nitrogen surpluses and the hydrological models GROWA/DEnUZ for assessing the nitrate leaching from the soil. For areas showing predicted nitrate concentrations in percolation water above the European Union （EU） groundwater quality standard of 50 mg nO3-n/L, effective agri-environmental reduction measures need to be derived and implemented to improve groundwater and surface water quality by 2015. The effects of already implemented agricultural policy are quantified by a baseline scenario projecting the n-surpluses from agricultural sector to 2015. The REGFLUD model is used to estimate the effects of this scenario concerning groundwater and surface water pollution by nitrate. From the results of the model analysis the needs for additional measures can be derived in terms of required additional n-surplus reduction and in terms of regional prioritization of measures. Research work will therefore directly support the implementation of the Water Framework Directive of the European Union in the Weser basin.

关键词： catchment management diffuse source pollution mitigation methods river basin management Water Framework Directive

Construction of Conservative numerical Fluxes for the Entropy Split Method

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Communications on Applied Mathematics and Computation 2023年第2期5卷 653-678页

作者： björn Sjögreen H.C.Yee Multid Analyses AB GothenburgSweden nASA Ames Research Center Moffett FieldCA 94035USA

The entropy split method is based on the physical entropies of the thermally perfect gas Euler *** Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in.j.Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et *** j Comp Phys 162:33-81,2000).Sj?green and Yee(j Sci Comput)recently proved that the entropy split method is entropy conservative and ***-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy *** current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux *** to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split ***,the Tadmor entropy conservative(EC)method(Tadmor in Acta numerica 12:451-512,2003)of the same order requires more operations count than the new *** the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et *** j Comput Phys 150:199-238,1999,j Comp Phys 162:3381,2000;Yee and Sj?green in.j.Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow *** of the ICOSAHOM09,june 22-26,Trondheim,norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock ***-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches.

关键词： Finite-difference method Entropy conservation Entropy splitting Shock capturing

Single and multiple stressor effect of road deicers and Cu on Atlantic salmon (Salmo salar) alevins from hatching till swim-up

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journal of Environmental Sciences 2018年第4期30卷 368-378页

作者： Urma Mahrosh bjФrn Olav Rosseland Brit Salbu Hans-Christian Teien nortuegian Uniuersity of Life Sciences Department of Environmental Sciences N-1432 As Norway national University of Sciences and Technology H-12 Islamabad Pakistan norwegian University of Life Sciences Department of Ecology and Natural Resource Management N-1432 As Norway

Road salts are frequently used for deicing of roads in the nordic countries. During snow-melt, the road run-off containing high concentrations of road salt and various metals such as Cu remobilized from sand, silt and dust may negatively influence organisms in downstream receiving water bodies. The present work focuses on the impact of road salt（naCl） and Cu, separately and in mixtures on Atlantic salmon alevins from hatching till swim-up. The results showed that high road salt concentrations could induce a series of negative effects in alevins such as reduced growth, deformities, delayed swim-up and mortality. For alevins exposed to all tested road salt concentrations（100–1000 mg/L）,mortality was significantly higher compared to control. In exposure to Cu solutions（5–20 μg Cu/L）, no effects on growth, morphology, swim-up or mortality of alevins compared to control were observed. In mixture solutions（road salt and Cu）, ultrafiltration of the exposure water demonstrated that only 20%–40% of Cu was present as positively charged low molecular mass（LMM） Cu species assumed to be bioavailable. When exposed to road salt and Cu mixtures, negative effects in alevins such as reduced growth, deformities,delayed swim-up and mortality were observed. The overall results indicated that the road salt application could seriously affect sensitive life stages of Atlantic salmon, and application of road salt should be avoided during the late winter–early spring period.

关键词： Road deicers Copper Atlantic salmon Alevins Biological effects