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Biomimetic Leukocyte Adhesion: A Review of Microfluidic and Computational Approaches and Applications

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journal of Bionic engineering 2008年第4期5卷 317-327页

作者： j. Hanzlik e. Cretekos K. A. Lamkin-Kennard Department of Mechanical engineering Rochester Institute of Technology Rochester

Leukocyte rolling and adhesion are complex physiological processes that have received a great deal of attention over the past decade. Significant increases in the knowledge base related to how leukocytes adhere in shear flows have occurred as a result of the development of novel experimental and computational techniques. Micro- and nano-fabrication techniques have enabled the development of novel flow devices for studying leukocyte adhesion in simple and complex geometries. Improvements in computer technology have enabled simulations of complex flow processes to be developed. As a result of these advances in knowledge related to leukocyte adhesion, numerous novel devices have been developed that mimic the leukocyte rolling and adhesion process. examples of these devices include cell separation and enrichment devices and targeted ultrasound contrast agents. Future advances related to leukocyte rolling and adhesion processes hold great promise for advancing our knowledge of disease processes as well as development of novel therapeutic devices.

关键词： leukocyte microfluidics hydrodynamics

AN ACCURATe NUMeRICAL SOLUTION OF A TWO DIMeNSIONAL HeAT TRANSFeR PROBLeM WITH A PARABOLIC BOUNDARY LAYeR

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journal of Computational Mathematics 1998年第1期16卷 27-39页

作者： C.Clavero j.j.H.Miller e.O'Riordan G.I.Shishkin Universidad de Zaragoza 西班牙 Trinity College 爱尔兰 Dublin City University 爱尔兰 Institute of Mathematics and Mechanics 俄罗斯

A singularly perturbed linear convection-diffusion problem for heat transfer in two dimensions with a parabolic boundary layer is solved numerically The numerical method consists of a special piecewise uniform mesh condensing in a neighbourhood of the parabolic layer and a standard finite difference operator satisfying a discrete maximum principle. The numerical computations demonstrate numerically that the method is epsilon-uniform in the sense that the Fate of convergence and error constant of the method are independent of the singular perturbation parameter epsilon. This means that no matter how small the singular perturbation parameter epsilon is, the numerical method produces solutions with guaranteed accuracy depending solely on the number of mesh points used.

关键词： linear convection-diffusion parabolic layer piecewise uniform mesh finite difference

Inscribing the core memories of killers

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Cellular & Molecular Immunology 2019年第2期16卷 104-105页

作者： Sarah j.Dulson Laurie e.Harrington Allan j.Zajac Department of Cell Developmentaland Integrative BiologyUniversity of Alabama at BirminghamBirminghamAL 35294United States Department of Microbiology University of Alabama at BirminghamBirminghamAL 35294United States

Recent studies on natural killer(NK)cells have challenged the dogma that immunological memory is a phenomenon restricted to the adaptive immune *** interactions between the NK cell receptor Ly49H and the murine cytomegalovirus virus(MCMV)-encoded glycoprotein m157 result in selective expansion of the Ly49H+NK cell subpopulation and the establishment of a long-lived memory-like population.1–3 Further,memory NK cells show augmented IFNγresponses,and transfer of the memory population into naive mice confers enhanced protection against infection-induced mortality.1 These observations along with cytotoxicity and cytokine secretion functions that overlap with CD8 T cells have led to the description of NK cells as a bridge between the innate and adaptive immune systems.

关键词： killer mortality cytotoxicity

Comprehensive insights into the thermal and mechanical effects of metallic glasses via creep

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journal of Materials Science & Technology 2022年第4期99卷 39-47页

作者： Z.R.Xu j.C.Qiao j.Wang e.Pineda D.Crespo School of Mechanics Civil Engineering and ArchitectureNorthwestern PolytechnicalUniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern PolytechnicalUniversityXi’an 710072China Department of Physics Barcelona Research Center in Multiscale Science and TechnologyInstitute of Energy TechnologiesUniversitat Politècnica de CatalunyaBarcelona 08019Spain

evolution of deformation and relaxation behaviors of a prototypical Cu_(46)Zr_(46)A_(l8)metallic glass was explored by extensive creep tests under both physical aging and cyclic *** insights into the microstructure-induced dynamic heterogeneity which accommodates creep deformation were successively revealed via experimental measurements and spectral *** annihilation of local defects within metallic glass with increasing annealing time and cyclic numbers was observed through the reduction of amplitude in both activation energy spectra and relaxation-time spectra,which were also accompanied by an ascending value of β_(KWW).It is further found that the corresponding deformation units within the metallic glass do not disappear permanently,but are recoverable over the course of cyclic *** apparent suppressed relaxation process can be gradually alleviated with increasing resuming time between two consecutive cycles,behaving differently from physical aging,which indicates a notable discrepancy between thermal treatment and mechanical treatment.

关键词： Metallic glasses Creep Physical aging Cyclic loading Relaxation-time spectrum

Assessing the utility of dissolved organic matter photoreactivity as a predictor of in situ methylmercury concentration

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journal of environmental Sciences 2018年第6期30卷 160-168页

作者： Sara j.Klapstein Susan e.Ziegler David A.Risk Nelson j.O'Driscoll environmental Science Program Memorial University of Newfoundland Department of earth Sciences St. Francis Xavier University Department of earth and environmental Science Acadia University

Methylmercury（MeHg） bioaccumulation is a growing concern in ecosystems worldwide. The absorption of solar radiation by dissolved organic matter（DOM） and other photoreactive ligands can convert MeHg into less toxic forms of mercury through photodemethylation. In this study, spectral changes and photoreactivity of DOM were measured to assess the potential to control photoreactions and predict in situ MeHg concentration. Water samples collected from a series of lakes in southwestern Nova Scotia in june, August, and September were exposed to controlled ultraviolet-A（UV-A） radiation for up to 24 hr. Dissolved organic matter photoreactivity, measured as the loss of absorbance at 350 nm at constant UV-A irradiation, was positively dependent on the initial DOM concentration in lake waters（r^2=0.94）. This relationship was consistent over time with both DOM concentration and photoreactivity increasing from summer into fall across lakes. Lake in situ MeHg concentration was positively correlated with DOM concentration and likely catchment transport in june（r = 0.77） but not the other sampling months. Despite a consistent seasonal variation in both DOM and Fe, and their respective correlations with MeHg, no discernable seasonal trend in MeHg was observed. However, a 3-year dataset from the 6 study lakes revealed a positive correlation between DOM concentration and both Fe（r = 0.91） and MeHg concentrations（r = 0.51） suggesting a more dominant landscape mobility control on *** DOM-MeHg relationships observed in these lakes highlights the need to examine DOM photoreactivity controls on MeHg transport and availability in natural waters particularly given future climate perturbations.

关键词： Methylmercury Dissolved organic carbon Photoreactions Kejimkujik National Park Freshwater lakes

Correlation Structures between Satellite All-Sky Infrared Brightness Temperatures and the Atmospheric State at Storm Scales

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Advances in Atmospheric Sciences 2022年第5期39卷 714-732页

作者： Yunji ZHANG eugene e.CLOTHIAUX David j.STeNSRUD Center for Advanced Data Assimilation and Predictability Techniques and Department of Meteorology and Atmospheric ScienceThe Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

This study explores the structures of the correlations between infrared(IR)brightness temperatures(BTs)from the three water vapor channels of the Advanced Baseline Imager(ABI)onboard the GOeS-16 satellite and the atmospheric ***-based data assimilation techniques such as the ensemble Kalman filter(enKF)rely on correlations to propagate innovations of BTs to increments of model state *** the three water vapor channels are sensitive to moisture in different layers of the troposphere,the heights of the strongest correlations between these channels and moisture in clear-sky regions are closely related to the peaks of their respective weighting *** cloudy regions,the strongest correlations appear at the cloud tops of deep clouds,and ice hydrometeors generally have stronger correlations with BT than liquid *** magnitudes of the correlations decrease from the peak value in a column with both vertical and horizontal *** how the correlations decrease depend on both the cloud scenes and the cloud structures,as well as the model *** correlations between BTs and moisture,as well as hydrometeors,in fully cloudy regions decrease to almost 0 at about 30 *** horizontal correlations with atmospheric state variables in clear-sky regions are broader,maintaining non-zero values out to~100 *** results in this study provide information on the proper choice of cut-off radii in horizontal and vertical localization schemes for the assimilation of *** also provide insights on the most efficient and effective use of the different water vapor channels.

关键词： severe storm remote sensing data assimilation numerical modeling

单个腺病毒颗粒的原子力显微镜液相成像及样品制备方法

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病毒学报 2015年第6期31卷 601-606页

作者：梁艳李晨 Mariska G M van Rosmalen Gijs j L Wuite Wouter H roos 中国水产科学研究院黄海水产研究所青岛266071 阿姆斯特丹自由大学

原子力显微镜(Atomic force microscopy,AFM)作为一种纳米级高分辨率的探针扫描显微镜,在病毒形态学研究等领域有广泛的应用。为更好地利用AFM在接近病毒生理环境(液相)中观测单个病毒颗粒,选择合适的基底吸附病毒样品是重要的前提保障... 详细信息

原子力显微镜(Atomic force microscopy,AFM)作为一种纳米级高分辨率的探针扫描显微镜,在病毒形态学研究等领域有广泛的应用。为更好地利用AFM在接近病毒生理环境(液相)中观测单个病毒颗粒,选择合适的基底吸附病毒样品是重要的前提保障。本文介绍了一种病毒样品制备及AFM液相成像方法。首先制备疏水化处理的玻璃盖玻片作为吸附基底,再将观察样品腺病毒重组载体颗粒(Adenovirus type 5F35,Ad5F35)吸附于基底上,建立在液相下单个病毒颗粒的原子力显微镜成像方法。通过该方法获取了单个腺病毒颗粒在液相下的高分辨率纳米级高度图(height image),且病毒颗粒保持了约90nm的正确测量高度。实验结果表明疏水化处理的玻璃基底具有良好的吸附力,有助于病毒颗粒牢固地吸附在基底上,且不会引起较大的形变。本研究为AFM观测病毒等生物样品提供了一种较为合适的吸附基底和在液相中的AFM成像方法,对后期开展病毒形态结构、物理属性及其与宿主细胞受体相互作用的研究打下基础。

关键词：原子力显微镜液相成像样品制备腺病毒颗粒

Bayesian model averaging(BMA)for nuclear data evaluation

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Nuclear Science and Techniques 2024年第11期35卷 193-218页

作者： e.Alhassan D.Rochman G.Schnabel A.j.Koning SCK CeN(Belgian Nuclear Research Centre) Boeretang 2002400 MolBelgium Laboratory for Reactor Physics and Thermal‑Hydraulics Paul Scherrer Institute5232 VilligenSwitzerland Nuclear Data Section International Atomic Energy Agency(IAEA)ViennaAustria Division of Applied Nuclear Physics Department of Physics and AstronomyUppsala UniversityUppsalaSweden

To ensure agreement between theoretical calculations and experimental data,parameters to selected nuclear physics models are perturbed and fine-tuned in nuclear data *** approach assumes that the chosen set of models accurately represents the‘true’distribution of considered ***,the models are chosen globally,indicating their applicability across the entire energy range of ***,this approach overlooks uncertainties inherent in the models *** this work,we propose that instead of selecting globally a winning model set and proceeding with it as if it was the‘true’model set,we,instead,take a weighted average over multiple models within a Bayesian model averaging(BMA)framework,each weighted by its posterior *** method involves executing a set of TALYS calculations by randomly varying multiple nuclear physics models and their parameters to yield a vector of calculated ***,computed likelihood function values at each incident energy point were then combined with the prior distributions to obtain updated posterior distributions for selected cross sections and the elastic angular *** the cross sections and elastic angular distributions were updated locally on a per-energy-point basis,the approach typically results in discontinuities or“kinks”in the cross section curves,and these were addressed using spline *** proposed BMA method was applied to the evaluation of proton-induced reactions on ^(58)Ni between 1 and 100 *** results demonstrated a favorable comparison with experimental data as well as with the TeNDL-2023 evaluation.

关键词： Bayesian model averaging(BMA) Nuclear data Nuclear reaction models Model parameters TALYS code system Covariances

endovascular treatment in anterior circulation stroke beyond 6.5 hours after onset or time last seen well:results from the MR CLeAN Registry

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Stroke & Vascular Neurology 2021年第4期6卷 572-580,I0037-I0048页

作者： Luuk Dekker esmee Venema F Anne V Pirson Charles B L M Majoie Bart j emmer Ivo G H jansen Maxim j H L Mulder Robin Lemmens Robert-jan B Goldhoorn Marieke j H Wermer jelis Boiten Geert j LycklamaàNijeholt Yvo B W e M roos Adriaan C G M van es Hester F Lingsma Diederik W j Dippel Wim H van Zwam Robert j van Oostenbrugge Ido R van den Wijngaard on behalf of the MR CLeAN Registry investigators Neurology Leiden University Medical CentreLeidenThe Netherlands Neurology Erasmus MCRotterdamThe Netherlands Public Health Erasmus MCRotterdamThe Netherlands Neurology Maastricht University Medical Centre+MaastrichtThe Netherlands Radiology and Nuclear Medicine Amsterdam University Medical CentreLocation AMCAmsterdamThe Netherlands Neurology University Hospitals LeuvenLeuvenBelgium Neurosciences Experimental Neurology and Leuven Brain InstituteUniversity of LeuvenLeuvenBelgium VIB Center for Brain&Disease ResearchLaboratory of NeurobiologyLeuvenBelgium Neurology Haaglanden Medical CentreDen HaagThe Netherlands Radiology Haaglanden Medical CentreDen HaagThe Netherlands Neurology Amsterdam University Medical CentreLocation AMCAmsterdamThe Netherlands Radiology Leiden University Medical CentreLeidenThe Netherlands Radiology Maastricht University Medical Centre+MaastrichtThe Netherlands

Background Randomised controlled trials with perfusion selection have shown benefit of endovascular treatment(eVT)for ischaemic stroke between 6 and 24 hours after symptom onset or time last seen ***,outcomes after eVT in these late window patients without perfusion imaging are largely *** assessed their characteristics and outcomes in routine clinical *** The Multicenter Randomized Clinical Trial of endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry,a prospective,multicentre study in the Netherlands,included patients with an anterior circulation occlusion who underwent eVT between 2014 and *** perfusion was no standard imaging *** used adjusted ordinal logistic regression analysis to compare patients treated within versus beyond 6.5 hours after propensity score matching on age,prestroke modified Rankin Scale(mRS),National Institutes of Health Stroke Scale,Alberta Stroke Programme early CT Score(ASPeCTS),collateral status,location of occlusion and treatment with intravenous *** included 3-month mRS score,functional independence(defined as mRS 0-2),and *** Of 3264 patients who underwent eVT,106(3.2%)were treated beyond 6.5 hours(median 8.5,IQR 6.9-10.6),of whom 93(87.7%)had unknown time of stroke *** perfusion was not performed in 87/106(80.2%)late window *** window patients were younger(mean 67 vs 70 years,per ASPeCTS(median 8 vs 9,petter collateral status(collateral score 2-3:68.3%vs 57.7%,p=0.03).No differences were observed in proportions of functional independence(43.3%vs 40.5%,p=0.57)or death(24.0%vs 28.9%,p=0.28).After matching,outcomes remained similar(adjusted common OR for 1 point improvement in mRS 1.04,95%CI 0.56 to 1.93).Conclusions Without the use of CT perfusion selection criteria,eVT in the 6.5-24-hour time window was not associated with poorer outcome in selected patients with favourable clinical and CT/C

关键词： treatment beyond Registry