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On the Naturally Induced sources for Obstacle scattering

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Communications in Computational Physics 2006年第6期1卷 974-983页

作者： Perrin s.meyer Marcos Capistran Yu Chen meyer sound 2832 San Pablo AvenueBerkeleyCA 94702-2204USA Universidad Autonoma del Estado de Morelos Av.Universidad No.1001Col.Chamilpa62210 CuernavacaMorelosMexico Courant Institute of Mathematical sciences New York University251 Mercer StreetNew YorkNY 10012-1110USA.

We introduce the equivalent sources for the Helmholtz equation and estab-lish their connections to the naturally induced sources for the sound-soft,sound-hard,and impedance obstacles for the inverse scattering problems of the Helmholtz *** two applications,we employ the naturally induced sources to improve the bound-ary integral equation formulations for the obstacle scattering problems,and develop a unified,straightforward approach to establishing boundary conditions governing the domain derivatives of scattered waves for the soft,hard,and impedance obstacles.

关键词： Naturally induced sources obstacle scattering domain derivatives

Inocula selection in microbial fuel cells based on anodic biofilm abundance of Geobacter sulfurreducens

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Chinese Journal of Chemical Engineering 2016年第3期24卷 379-387页

作者： Guotao sun Diogo de sacadura Rodrigues Anders Thygesen Geoffrey Daniel Dinesh Fernando Anne s.meyer Center for BioProcess Engineering Department of Chemical and Biochemical EngineeringTechnical University of Denmark Department of Forest Products Swedish University of Agricultural Sciences

Microbial fuel cells （MFCs） rely on microbial conversion of organic substrates to electricity. The optimal perfor- mance depends on the establishment of a microbial community rich in electrogenic bacteria. Usually this micro- bial community is established from inoculation of the MFC anode chamber with naturally occurring mixed inocula. In this study, the electrochemical performance of MFCs and microbial community evolution were eval- uated for three inocula including domestic wastewater （DW）, lake sediment （Ls） and biogas sludge （Bs） with varying substrate loading （Lsub） and external resistance （Rext） on the MFC. The electrogenic bacterium Geobacter sulfurreducens was identified in all inocula and its abundance during MFC operation was positively linked to the MFC performance. The Is inoculated MFCs showed highest abundance （18% ± 1%） of G. sulfurreducens, maximum current density [Imax = （690 ± 30） mA.m 2] and coulombic efficiency （CE = 29% ±1%） with acetate as the substrate./max and CE increased to （1780 ± 30） mA.m-2 and 58%± 1%, respectively, after decreasing the Rext from 1000 Ωto 200 Ω, which also correlated to a higher abundance ofG. sulfurreducens （21% ±0.7%） on the MFC anodic biofilm. The data obtained contribute to understanding the microbial community response to Lsub and Roy, for of timizing electricity eneration in MFCs.

关键词： Lake sediment Coulombic efficiency Denaturing gradient gel electrophoresis Geobacter sulfurreducens Anode polarisation resistance

Investigation of normal,lateral,and oblique impact of microscale projectiles into unidirectional glass/epoxy composites

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Defence Technology（防务技术） 2022年第11期18卷 1960-1978页

作者： Christopher s.meyer Isabel G.Catugas John W.Gillespie Jr. Bazle Z.Gama Haque University of Delaware Center for Composite Materials(UD-CCM) 101 Academy StreetNewarkDE19716USA

spacesuits and spacecraft must endure high velocity impacts from micrometeoroids. This work considers the impact of 100 μm diameter projectiles into composite targets at velocities from 0.5 km/s to 2 km/*** work begins by presenting an energy-based theoretical model relating depth of penetration(Do P)and impact force to impact velocity, characteristic time, and threshold velocity and force. Next, this work compares numerical simulations of normal impact on composites to the theoretical model. Numerical simulations are conducted with Ls-DYNA and the well-known composite model, MAT-162. The numerical models consider unidirectional s2-glass fiber reinforced sC-15 epoxy composite laminates. The numerical model shows good correlation with the theoretical model. The numerical model also investigates lateral impact, parallel to the fiber direction, and oblique impact at angles from 30°to 82.5°.This work decomposes oblique impact into normal and lateral components, and compares them with normal and lateral impact results. The results show good correlation of the normal component of oblique results with the theoretical model. This numerical and theoretical study focuses on Do P, velocity, and penetration resistance force as functions of time. The theoretical model and numerical simulations are used to determine new Do P parameters: characteristic time of depth of penetration and threshold impact velocity. These models are a first step in developing the capability to predict Do P for oblique,microscale, high-speed impact on composite materials.

关键词： Microscale Hypervelocity impact Composites Erosion Penetration

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

A Mathematical Model for simultaneous saccharification and Co-fermentation （ssCF） of C6 and C5 sugars

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Chinese Journal of Chemical Engineering 2011年第2期19卷 185-191页

作者： Ricardo Morales-Rodriguez Krist V.Gernaey Anne s.meyer Gürkan sin Computer Aided Process Engineering Center (CAPEC) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark PROCEss Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark BIOENG Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark

Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search *** this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （ssCF） of C6 and C5 *** model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and *** inhibition of ethanol on cellulose conversion is introduced in order to increase the *** mathematical model for the ssCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill *** fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） *** promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.

关键词： bioethanol dynamic modeling simultaneous saccharification and co-fermentation

The contribution of small leaks in a baghouse filter to dust emission in the PM2.s range-A system approach

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Particuology 2017年第1期15卷 40-52页

作者： Oliver Kurtz Jorg meyer Gerhard Kasper Institut for Mechanische Verfahrenstechnik und Mechanik Karlsruhe Institute of Technology 76131 Karlsruhe Germany Freudenberg Filtration Technologies 69465 WeinheimGermany.

The contribution of leakage in a baghouse filter （defined as a short circuit between the upstream and downstream sides of the filter） to the emission of fine particles is quantified in comparison to other dust emission sources, and the influence of key operating variables on overall system response is analyzed. The study was conducted on a well-maintained pilot-scale filter unit （9 bags of 500 g/m^2 calendered polyester needle felt; total surface area 4.2 m^2） operated in Ap-controlled mode over a range of pulsing intensities, with two types of test dust （one free-flowing and the other cohesive） at inlet concentrations of 10 and 30 g/m^3. Leaks included single holes between 0.5 and 4 mm diameter, intentionally placed in either the plenum plate or one of the filter bags, as well as seamlines from bag confectioning. Emissions were sep- arated by source into a transient contribution due to dust penetration through the filter bags after each cleaning pulse, and a continuous contribution from leaks. This separation was based on a novel method of data processing that relies on time-resolved concentration measurements with a specially calibrated optical particle counter. Tiny leaks on the order of 1 mm generated the same emission level as all the bags combined, and dominated continuous emissions. The equivalent leak cross section （leakage = media emission） was about 1 ppm of the total installed filter surface, independent of upstream dust concentra- tion. Leakage through open seamlines amounted to 75% of media emissions in case of free-flowing test dust. Leakage was restricted to aerodynamic diameters less than ~5 μm （roughly the PM2.s mass frac- tion）. For comparison, time-averaged mass penetration through conventional needle-felt media ranged from about 10^-5 to 10^-6, depending on cohesiveness of the particle material and pulse cleaning intensity, giving emission levels between about 0.02 and 0.2 mg/m^3 at the reference concentration of 10 R/m^2.

关键词： Air filtration Baghouse Pulse-cleaned filters Leaks PM2.5 Dust emission

“Bull’s eye”appearance of hepatocellular adenomas in patients with glycogen storage disease type I-atypical magnetic resonance imaging findings:Two case reports

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World Journal of Clinical Cases 2021年第4期9卷 871-877页

作者： Federica Vernuccio stephanie Austin Mathias.meyer Cynthia D Guy Priya s Kishnani Daniele Marin Department of Biomedicine Neuroscience and Advanced DiagnosticsUniversity of PalermoPalermo 90100Italy Departments of Pediatrics Duke University Medical CenterDurhamNC 27710United States Department of Radiology Duke University Medical HospitalDurhamNC 27708United States Department of Pathology Duke UniversityDurhamNC 27710United States Division of Medical Genetics Department of PediatricsDuke University Medical CenterDurhamNC 27710United States Department of Radiology Duke University Medical CenterDurhamNC 27710United States

BACKGROUND Hepatocellular adenomas are rare tumors that can occur in patients with glycogen storage disease type *** sUMMARY We herein report two cases of histologically proven hepatocellular adenomas in patients with glycogen storage disease type *** resonance imaging(MRI)was performed after bolus injection of gadoxetate disodium,a liver-specific gadolinium-based MRI contrast *** the present cases,some of the hepatocellular adenomas showed unexpectedly a“bull’s eye”appearance on T2-weighted and post-contrast images,which was not previously described as imaging findings of hepatocellular adenomas in glycogen storage disease.A bull’s eye appearance on T2-weighted images can be encountered in both benign(i.e.,abscess)or malignant(i.e.,epithelioid hemangioendothelioma,cholangiocarcinoma,and metastases)hepatic *** We present two cases of hepatocellular adenomas in patients with glycogen storage disease type 1,in which gadoxetate disodium-MRI showed atypical imaging findings for hepatocellular *** present there is no systematic study evaluating MRI findings of hepatocellular adenomas in patients with glycogen storage disease,further studies are needed to specifically investigate this issue.

关键词： Glycogen storage disease Hepatocellular adenoma Bull’s eye Magnetic resonance imaging Case report Gadoxetate disodium