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CFD modeling and laboratory studies of dust cleaning efficacy of an efficient four stage non-clogging impingement filter for flooded-bed dust scrubbers

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International Journal of Coal Science & Technology 2022年第2期9卷 211-219页

作者： Ashish Ranjan Kumar Neeraj Gupta steven schafrik Department of Mining Engineering University of KentuckyLexingtonKYUSA Department of Mining and Nuclear Engineering Missouri University of Science and Technology1400 N.Bishop AveRollaMO 65401USA

Fibrous-type flters are used to capture dust particles in mining and other occupations where personnel are exposed for prolonged *** cleansing devices including fooded-bed dust scrubbers use these mesh-type multi-layered *** flters trap dust particles efciently on their surface and inside their ***,their continued operation leads to dust build-up and *** results in increased resistance of the flter and lowered airfow rate through the *** could potentially enhance the exposure of the miners.A non-clogging self-cleaning impingement screen type dust flter was designed by the authors for use in mining and industrial dust cleansing *** flter guides dirt-laden air through rapidly turning paths which forces it to shed heavier *** particles impact one of the impermeable solid metallic flter surfaces and are removed from the airstream.A full cone water spray installed upstream prevents any surface buildup of *** paper summaried the computer models generated to show the flter operations and laboratory experiments including optical particle counting to establish the cleaning efciency.

关键词： Dust flter Computational fuid dynamics modeling Iso-kinetic sampling Optical particle counting Flooded-bed dust scrubber

Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics

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Neural Regeneration Research 2025年第11期20卷 3179-3192页

作者： Pieter-Jan Serneels Julie D.De Schutter Lies De Groef Lieve Moons steven Bergmans KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionNeural Circuit Development&Regeneration Research GroupLeuvenBelgium KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionCellular Communication&Neurodegeneration Research GroupLeuvenBelgium

Decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and ***,recent studies employing single-cell RNA sequencing techniques have uncovered novel cell states,prompting a revision of the existing *** forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature *** new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological *** this uniform terminology will facilitate comparison and integration of data across ***,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating ***,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination ***,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction.

关键词： animal models demyelination fish mammals multiple sclerosis myelin neurodegeneration oligodendrocytes oligodendroglial lineage remyelination

Applying machine learning to study fluid mechanics

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Acta Mechanica Sinica 2021年第12期37卷 1718-1726页

作者： steven L.Brunton Department of Mechanical Engineering University of WashingtonSeattleWA 98195USA

This paper provides a short overview of how to use machine learning to build data-driven models in fluid *** process of machine learning is broken down into five stages:(1)formulating a problem to model,(2)collecting and curating training data to inform the model,(3)choosing an architecture with which to represent themodel,(4)designing a loss function to assess the performance of the model,and(5)selecting and implementing an optimization algorithm to train the *** each stage,we discuss how prior physical knowledge may be embedding into the process,with specific examples from the field of fluid mechanics.

关键词： Machine learning Fluid mechanics Physics-informed machine learning Neural networks Deep learning

Some highlights of the Gamma-ray first four years of the Fermi Space Telescope

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Frontiers of physics 2013年第6期8卷 693-713页

作者： steven Ritz Department of Physics and the SCIPP University of California Santa Cruz Santa Cruz CA 95064 USA

The Fermi Gamma-ray Space Telescope, formerly called GLAST, measures the cosmic gamma-ray flux in the energy range 8 keV to 〉 300 GeV. In addition to breakthrough capabilities in energy coverage and localization, the very large field of view enables observations of 20~ of the sky at any instant, and the entire sky on a timescale of a few hours. With its launch in 2008, Fermi opens a new and important window on a wide variety of phenomena, including pulsars, black holes and active galactic nuclei, gamma-ray bursts, supernova remnants and the origins of cosmic rays, and searches for hypothetical new phenomena such as particle dark matter annihilations. A brief overview and selected science highlights from the first four years are provided.

关键词： high-energy gamma-ray astrophysics dark matter fundamental physics tests spacebased astrophysics space-based particle astrophysics gamma-ray bursts blazars pulsars

What really happens in strongly correlated superconductors:insights from a quantum Monte-Carlo study of high temperature superconductivity in FeSe films

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Science Bulletin 2016年第12期61卷 911-913页

作者： steven A.Kivelson Department of Physics Stanford University

BCS theory and its extensions form the basis of a compelling and elegant understanding of the properties of conventional ***,it is a weak-coupling theory,organized around the infinitesimal‘‘Cooper’’instability of the Fermi *** is not merely a theoretical abstraction:Schrieffer(among others)has emphasized that it is only because the normal state above T_c is

关键词：高温超导电性蒙特卡罗方法超导体强关联薄膜量子 BCS理论扩展形式

Seven possible states of geospatial data with respect to map projection and definition: a novel pedagogical device for GIS education

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Geo-Spatial Information Science 2018年第4期21卷 288-293页

作者： steven E.Greco Department of Human Ecology University of CaliforniaDavisCAUSA

Conceptually,the theory and implementation of“map projection”in geographic information system(GIS)technology is difficult to comprehend for most introductory students and novice *** this difficulty is the concept of a“map projection file”that defines map projection parameters of geo-spatial *** problem of the“missing projection file”appears ubiquitous for all users,especially in practice where data is widely *** common problem is inadvertent misapplication of the“Define Projection”tool that can result in a GIS dataset with an incorrectly defined map projection *** education should provide more guidance in differentiating the concepts of map projection versus projection files by increasing understanding and minimizing common errors.A novel pedagogical device is introduced in this paper:the seven possible states of GIS data with respect to map projection and *** seven possible states are:(1)a projected coordinate system(PCS)that is correctly defined,(2)a PCS that is incorrectly defined,(3)a PCS that is undefined,(4)a geographic coordinate system(GCS)that is correctly defined,(5)a GCS that is incorrectly defined,(6)a GCS that is undefined,and(7)a *** created automated troubleshooting tools to determine a missing map projection file are discussed.

关键词： GIS education map projection error map projection file define projection

Cancer in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 378-389页

作者： steven H Itzkowitz Division of Gastroenterology Department of Medicine Mount Sinai School of Medicine New York City NY 10029 United States

Patients with long-standing inflammatory bowel disease (IBD) have an increased risk of developing colorectal cancer (CRC). Many of the molecular alterations responsible for sporadic colorectal cancer, namely chromosomal instability, microsatellite instability, and hypermethylation, also play a role in colitis-associated colon carcinogenesis. Colon cancer risk in inflammatory bowel disease increases with longer duration of colitis, greater anatomic extent of colitis, the presence of primary sclerosing cholangitis, family history of CRC and degree of inflammation of the bowel. Chemoprevention includes aminosalicylates, ursodeoxycholic acid, and possibly folic acid and statins. To reduce CRC mortality in IBD, colonoscopic surveillance with random biopsies remains the major way to detect early mucosal dysplasia. When dysplasia is confirmed, proctocolectomy is considered for these patients. Patients with small intestinal Crohn’s disease are at increased risk of small bowel adenocarcinoma. Ulcerative colitis patients with total proctocolectomy and ileal pouch anal- anastomosis have a rather low risk of dysplasia in the ileal pouch, but the anal transition zone should be monitored periodically. Other extra intestinal cancers, such as hepatobiliary and hematopoietic cancer, have shown variable incidence rates. New endoscopic and molecular screening approaches may further refine our current surveillance guidelines and our understanding of the natural history of dysplasia.

关键词： Colon cancer Inflammatory bowel disease Dysplasia Chemoprevention Colonoscopy Genomicinstability

VARIABLE STEP-SIZE IMPLICIT-EXPLICIT LINEAR MULTISTEP METHODS FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven J. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have been developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementable variable step-size implicit-explicit （VSIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VSIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the Burgers＇ equation. These results demonstrate that by varying the time step-size, VSIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical behavior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variable step-size Zero-stability Burgers' equation.

RNAi screen in Drosophila yields a fat catch of Hedgehog

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Protein & Cell 2010年第3期1卷 205-206页

作者： steven Y Cheng Center for Regenerative Medicine and Department of Developmental Genetics Nanjing Medical UniversityNanjing 210029China

Obesity,the scrooge of technological advances of the human society,just had its genetic makings revealed once again.A large international team led by Josef *** and Harald Esterbauer from the Austrian Academy of Sciences and Medical University of Vienna have conducted a systemic hunt for obesity genes in adult Drosophila using an ingenious design of RNAi-based screening strategy(Pospisilik et al.,2010).This study covered 78%of Drosophila genome,including 30%of genes that would otherwise cause embryonic lethality if inactivated by conventional *** findings included~500 obesity genes that have their functions linked to control of differentiation along neuronal,muscle,and oenocyte lineages,but components of the Hedgehog(Hh)signaling distinguished themselves as the top-scoring hits。

关键词： Hedgehog otherwise finding