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Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness

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Communications on Applied Mathematics and Computation 2024年第2期6卷 811-836页

作者： Michael Franco Per-Olof Persson Will Pazner Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720-3840USA Fariborz Maseeh Department of Mathematics and Statistics Portland State UniversityPortlandOR 97201USA

We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated *** preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the *** convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging *** approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion *** goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced *** tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence *** present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the *** demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion ***,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack.

关键词： Subregion correction Nested Krylov Geometrically localized stiffness

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Serum ferritin and the risk of early-onset colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3496-3506页

作者： Adam L Urback Kylee Martens Hannah Stowe McMurry Emerson Y Chen Caitlin Citti Anil Sharma Adel Kardosh Joseph J Shatzel Division of Internal Medicine Oregon Health&Science UniversityPortlandOR 97239United States Division of Hematology and Medical Oncology Knight Cancer InstituteOregon Health&Science UniversityPortlandOR 97239United States Division of Gastroenterology&Hepatology Oregon Health&Science UniversityPortlandOR 97239United States

BACKGROUND The incidence of early-onset colorectal cancer(EO-CRC)is rising in the United States,and is often diagnosed at advanced *** serum ferritin is often incidentally discovered in young adults,however,the indication for endoscopy in EO-CRC is *** To compare serum ferritin between patients with EO-CRC and healthy controls(HCs),and examine the association of serum ferritin in EO-CRC with patient-and disease-specific *** A retrospective study of patients<50 years with newly-diagnosed EO-CRC was conducted from 1/2013-12/*** were included if serum ferritin was measured within 2 years prior to 1 year following CRC histologic *** supplement the analysis,a cohort of HCs meeting similar inclusion and exclusion criteria were identified for comparison.A sensitivity analysis including only patients with serum ferritin obtained at or before diagnosis was separately performed to minimize risk of *** Among 85 patients identified with EO-CRC(48 females),the median serum ferritin level was 26 ng/mL(range<1-2759 ng/mL).Compared to HCs(n=80211),there were a higher proportion of individuals with EO-CRC with serum ferritin<20 ng/mL(female 65%,male 40%)versus HCs(female 32.1%,male 7.2%)age 29-39 years(P=0.002 and P<0.00001,respectively).Stage IV disease was associated with significantly higher serum ferritin compared to less advanced stages(P<0.001).Serum ferritin obtained before or at the time of diagnosis was lower than levels obtained after *** findings were confirmed in the sensitivity *** Severe iron deficiency may indicate an increased risk of EO-CRC,particularly at earlier *** studies defining the optimal serum ferritin threshold and routine incorporation of serum ferritin in screening algorithms is essential to develop more effective screening strategies for EO-CRC.

关键词： Early-onset Young-onset Colorectal cancer Age Ferritin Iron deficiency

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Debris Fan Produced by Failure of Canyon-Blocking Pyroclastic Flows

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Journal of Water Resource and Protection 2024年第5期16卷 328-360页

作者： Michael L. Cummings Department of Geology Portland State University Portland Oregon USA

Ash-rich pyroclastic flows from the cataclysmic eruption of Mount Mazama (~7700 yr. B. P.), Cascade volcanic arc, Oregon, entered and blocked the narrow, bedrock-lined canyon of the Williamson River approximately 35 to 44 km from the source volcano. The blockage impounded a body of water which then released producing four stratigraphic units in the downstream debris fan. The four stratigraphic units are a boulder core comprised of locally sourced bedrock boulders and three sand-rich units including a fine-grained sand unit, a sandy pumice gravel (±basalt/hydrovolcanic tuff) unit, and a pumice pebble-bearing, crystal-rich sand unit. Hand-drilled auger holes up to ~1.6 m deep were used to obtain samples of the sand-rich units. Units were delimited using surface and down-hole observations, composition and texture, estimated density, statistical parameters of grain size, and vertical and lateral distribution of properties. Overtopping followed by rapid incision into the ash-rich pyroclastic flows progressively cleared the canyon, but a bedrock knickpoint near the head of the canyon limited the volume of debris available for transport to about 0.04 km3 to 0.08 km3. Co-deposition of bedrock boulders and lithic-rich sand was followed by rapid deposition with minimal reworking of remobilized pyroclastics. Continued draining of the impounded lake sent hyperconcentrated flows onto the debris fan depositing pumice-rich gravels that graded upward to crystal-rich sands.

关键词： Outburst Flood Mount Mazama Debris Fan Canyon Blockage Pyroclastic Flows

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Monolayer graphene/GaN heterostructure photodetector with UV‑IR dual‑wavelength photoresponses

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Frontiers of Optoelectronics 2024年第2期17卷 61-68页

作者： Junjun Xue Jiaming Tong Zhujun Gao Zhouyu Chen Haoyu Fang Saisai Wang Ting Zhi Jin Wang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China portland Institute Nanjing University of Posts and TelecommunicationsNanjing 210023China

An ultraviolet-infrared(UV-IR)dual-wavelength photodetector(PD)based on a monolayer(ML)graphene/GaN heterostructure has been successfully fabricated in this *** ML graphene was synthesized by chemical vapor deposition(CVD)and subsequently transferred onto GaN substrate using polymethylmethacrylate(PMMA).The morphological and optical properties of the as-prepared graphene and GaN were *** fabricated PD based on the graphene/GaN heterostructure exhibited excellent rectify behavior by measuring the current–voltage(I–V)characteristics under dark conditions,and the spectral response demonstrated that the device revealed an UV-IR dual-wavelength *** addition,the energy band structure and absorption properties of the ML graphene/GaN heterostructure were theoretically investigated based on density functional theory(DFT)to explore the underlying physical mechanism of the two-dimensional(2D)/three-dimensional(3D)hybrid heterostructure PD *** work paves the way for the development of innovative GaNbased dual-wavelength optoelectronic devices,offering a potential strategy for future applications in the field of advanced photodetection technology.

关键词： Wide bandgap semiconductors Graphene Dual-wavelength Photodetector

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Assembling S-scheme heterojunction between basic bismuth nitrate and bismuth tungstate with promoting charges’separation for accelerated photocatalytic sulfamethazine degradation

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Journal of Materials Science & Technology 2024年第4期171卷 185-197页

作者： Wenhan Chen Meng Dai Li Xiang Shan Zhao Shuguang Wang Zuoli He Shandong Key Laboratory of Water Pollution Control and Resource Reuse Shandong Key Laboratory of Environmental Processes and HealthSchool of Environmental Science and EngineeringShandong UniversityQingdao 266237China CEDAR Knight Cancer InstituteSchool of MedicineOregon Health and Science UniversityPortlandOR 97201United States Weihai Research Institute of Industrial Technology of Shandong university Shandong UniversityWeihai 264209China

The S-scheme heterojunction has garnered increasing attention due to its remarkable oxidation capacity and efficient separation of photogenerated *** this study,a one-pot glycerol-assisted hydrothermal process was utilized to successfully synthesize S-scheme heterojunction photocatalysts comprising basic bismuth nitrate(BBN)and bismuth tungstate(BWO).Interestingly,the BBN/BWO heterogeneous photo-catalysts exhibited the highest photocatalytic *** optimized product achieved the degradation of sulfamethazine(SMZ)within 1 h,with a kinetic constant(k)value of 0.05818 min^(−1).The degradation process was influenced significantly by·O^(2)−and h^(+)*** determine the degradation pathway of SMZ in the presence of BBN/BWO-0.6,liquid chromatography-mass spectrometry(LC-MS)analysis was performed,which revealed a decrease in the toxicity of intermediates and *** enhanced pho-tocatalytic activity can be attributed to the internal electric field(IEF)of the S-scheme heterojunction between BBN and BWO,effectively promoting the separation of photogenerated *** research presents a viable approach for developing S-scheme heterojunctions in SMZ photodegradation and other environmental applications.

关键词： Photocatalysis S-scheme Heterojunction Bi_(2)WO_(6) Sulfamethazine

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Neuronomodulation of Excitable Neurons

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Neuroscience Bulletin 2024年第1期40卷 103-112页

作者： Yizhang Chen Lin Xiao Jian Qiu Institute of Neuroscience Second Military Medical UniversityShanghai 200433China Institute for Brain Research and Rehabilitation Key Laboratory of BrainCognition and Education Sciences of Ministry of EducationSouth China Normal UniversityGuangzhou 510631China Department of Chemical Physiology and Biochemistry Oregon Health and Science UniversityPortlandOR 97239USA

Neuronomodulation refers to the modulation of neural conduction and synaptic transmission(i.e.,the conduction process involved in synaptic transmission)of excitable neurons via changes in the membrane potential in response to chemical substances,from spillover neuro-transmitters to paracrine or endocrine hormones circulating in the *** can be direct or indirect,depending on the transduction pathways from the ligand binding site to the ion pore,either on the same molecule,*** ion channel,or through an intermediate step on different *** major players in direct neurono-modulation are ligand-gated or voltage-gated ion *** key process of direct neuronomodulation is the binding and chemoactivation of ligand-gated or voltage-gated ion channels,either orthosterically or allosterically,by various *** neuronomodulation involves metabotropic receptor-mediated slow potentials,where steroid hormones,cytokines,and chemokines can implement these *** neuronomodulation is of great significance for understanding the physiological mechanisms of brain function,and the occurrence and treatment of diseases.

关键词： Neuron Membrane potential Excitability Chemoactivation Neuronomodulation

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Design of compact integrated diamond nitrogen-vacancy center quantum probe

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Chinese Physics B 2024年第5期33卷 409-415页

作者：夏圣开卢文韬赵旭彤薛雅文许增博葛仕宇汪洋虞林嫣卞雨辰安思瀚杨博向建军杜关祥 School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China portland Institute Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Economics Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu Institute of Quality and Standardization Nanjing 210012China Chengdu Analog Circuit Technology Inc. Chengdu 201203China

An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring *** flexible polyimide(PI)as the substrate medium,we design a circular microstrip antenna,which can achieve a bandwidth of 140 MHz at Zeeman splitting frequency of 2.87 GHz,specifically suitable for NV center ***,this antenna is seamlessly fixed at a three-dimensional-printed cylindrical support,allowing the optical fiber tip to extend out of a dedicated *** mitigate errors originating from processing,precise tuning within a narrow range can be achieved by adjusting the conformal ***,we image the microwave magnetic field around the integrated probe with high resolution,and determine the suitable area for placing the fiber tip(SAP).

关键词： nitrogen-vacancy center conformal antenna integrated probe magnetic field imaging

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Micron-sized fiber diamond probe for quantum precision measurement of microwave magnetic field

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Chinese Physics B 2024年第8期33卷 186-190页

作者：卢文韬夏圣开陈爱庆何康浩许增博陈艺涵汪洋葛仕宇安思瀚吴建飞马艺菡杜关祥 portland Institute Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Telecommunication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Economics Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic and Optical Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Electronic Science and Technology National University of Defense TechnologyChangsha 410000China

We present a quantitative measurement of the horizontal component of the microwave magnetic field of a coplanar waveguide using a quantum diamond probe in fiber *** measurement results are compared in detail with simulation,showing a good *** simulation shows fiber diamond probe brings negligible disturbance to the field under measurement compared to bulk *** method will find important applications ranging from electromagnetic compatibility test and failure analysis of high frequency and high complexity integrated circuits.

关键词： quantum precision measurement electromagnetic field diamond NV center quantum metrology

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Evaluating for unrecognized deficits in perimetry associated with functional upper eyelid malposition

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Advances in Ophthalmology Practice and Research 2024年第1期4卷 39-44页

作者： Linyan Wang Davin C.Ashraf Michael Deiner Oluwatobi O.Idowu Seanna R.Grob Bryan J.Winn M Reza Vagefi Robert C.Kersten Department of Ophthalmology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiangChina Department of Ophthalmology University of CaliforniaSan FranciscoUSA Department of Ophthalmology Oregon Health and Science UniversityPortlandUSA Department of Ophthalmology Tufts Medical CenterBostonUSA Department of Ophthalmology University of UtahSalt Lake CityUtahUSA

Objective:To investigate whether functional upper eyelid malposition is associated with unrecognized deficits in automated perimetry among glaucoma patients by examining patients undergoing eyelid surgery who had not been identified as requiring eyelid taping during glaucoma field ***:In this retrospective pre-post study,an automated database search followed by manual chart review was used to identify eligible patients from January 2012 to March *** patients had reliable visual field testing within two years before and after functional upper blepharoplasty or ptosis repair and no comorbid ocular *** part of routine practice,glaucoma visual field technicians taped patients with pupil-obstructing eyelid malposition;taped examinations were excluded from *** and demographic characteristics,mean deviation,and pattern standard deviation were evaluated within a two year period before and after eyelid ***:The final analysis included 60 eyes of 38 *** in visual field parameters after eyelid surgery did not reach statistical significance in crude or adjusted *** patients with ptosis,the margin reflex distance-1 was not associated with change in mean deviation after surgery(Pearson R2=0.0061;P=0.700).Five of 17 eyes excluded from analysis due to unreliable pre-operative visual fields demonstrated substantial improvement after ***:Functional upper eyelid malposition does not appear to cause spurious visual field abnormalities among glaucoma patients with reliable visual fields who were determined not to require eyelid taping at the time of their visual *** visual fields could be a sign of eyelid interference in this population.

关键词： Visual field Ptosis Dermatochalasis Glaucoma Perimetry Visually significant

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Distinct and Additive Effects of Alcohol and Thiamine Deficiency in the Developing Brain: Relevance to Fetal Alcohol Spectrum Disorder

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Journal of Behavioral and Brain Science 2024年第6期14卷 161-186页

作者： Suzanne M. de la Monte Elizabeth Silbermann Ming Tong Departments of Pathology (Neuropathology) Neurology and Neurosurgery Brown University Providence RI USA Department of Medicine Brown University Providence RI USA Rhode Island Hospital Providence RI USA Women & Infants Hospital Providence RI USA Warren Alpert Medical School of Brown university Providence RI USA portland VA Medical Center Oregon Health & Science University Portland OR USA

Background: Neurodevelopmental abnormalities in fetal alcohol spectrum disorder (FASD) are linked to brain insulin resistance and oxidative stress. However, the role of thiamine deficiency as a distinct or additive factor in the pathogenesis of the neurodevelopmental and metabolic derangements in FASD has not been determined. Methods: Control and ethanol-exposed human PNET2 cerebellar neuronal cells and rat cerebellar slice cultures were treated with vehicle or pyrithiamine (Pyr) to assess independent and additive effects of thiamine deficiency on ethanol-mediated neurotoxicity, mitochondrial dysfunction, insulin resistance, inhibition of neuronal and glial genes, and oxidative stress. Results: Pyr treatments (0 - 200 µM) caused dose-dependent cell loss (Crystal Violet assay) and reduced mitochondrial function (MTT assay) in PNET2 neuronal cultures. Ethanol alone (100 mM) significantly reduced PNET2 neuronal viability, MTT activity, and ATP production. Over the broad dose range of Pyr treatment, ethanol significantly reduced ATP content and cell number and increased mitochondrial mass (MitoTracker Green). Ex vivo cerebellar slice culture studies revealed ethanol-induced developmental architectural disruption that was substantially worsened by Pyr. The adverse effects of ethanol were linked to increased lipid peroxidation and inhibition of asparatyl-asparaginyl-β-hydroxylase (ASPH) expression. The independent and additive effects of Pyr were associated with increased cytotoxicity, lipid peroxidation, Caspase 3 activation, and Tau accumulation. Conclusions: During development, alcohol exposure and thiamine deficiency exert distinct but overlapping molecular pathologies that ultimately impair the structure and function of cerebellar neurons. While both insults drive cell loss and mitochondrial dysfunction with increased lipid peroxidation, ethanol’s additional inhibitory effects on ASPH reflect impairments in insulin and IGF signaling. In contrast, Pyr’s main adverse e

关键词： Fetal Alcohol Spectrum Disorder Thiamine Deficiency Cerebellum Slice Culture Pyrithiamine

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