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Open Journal of Veterinary Medicine 2020年第3期10卷 27-38页

作者： Daniel Shock steven roche Denis Nagel Merle Olson ACER Consulting Guelph Canada Alberta Veterinary Labs/Solvet Inc. Calgary Canada

The non-steroidal anti-inflammatory drug meloxicam is commonly used as adjunct therapy for neonatal calf diarrhea to control pain and inflammation. The objective of this study was to compare the pharmacokinetics of meloxicam in diarrheic pre-ruminant dairy calves dosed either orally or subcutaneously. Twelve pre-ruminant male dairy calves with mild to moderate diarrhea were randomly assigned to receive one of four treatments (three per group): subcutaneous meloxicam (SM, 0.5 mg/kg body weight);an oral bolus meloxicam suspension (OM, 1 mg/kg body weight);an oral meloxicam suspension added to a feeding of oral electrolytes (EM, 1 mg/kg body weight);and an oral meloxicam suspension added to a feeding of milk replacer (MM, 1 mg/kg body weight). The predicted pharmacokinetic parameters for OM, MM, EM, and SM groups were: half-life (56.8 ± 21.7 vs. 136.0 ± 26.6 vs. 85.2 ± 21.7 vs. 36.3 ± 21.7 h), Cmax (4.3 ± 0.4 vs. 3.7 ± 0.4 vs. 3.9 ± 0.4 vs. 2.1 ± 0.4 μg/mL), Tmax (13.3 ± 4.0 vs. 10.7 ± 4.0 vs. 13.3 ± 4.0 vs. 2.7 ± 4.0 h), and AUC0-∞ (383.4 ± 126.8 vs. 877.8 ± 155.3 vs. 457.1 ± 126.8 vs. 126.4 ± 126.8 h * μg/mL). Oral meloxicam, especially MM, had extended elimination phases relative to SM. All meloxicam therapies provided effective therapeutic levels but all oral therapies (1 mg/kg) provided longer durations of activity than injectable meloxicam (0.5 mg/kg).

关键词： Meloxicam Dairy Calves Pharmacokinetics Diarrhea Anti-Inflammatory

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陆上地震勘探数据处理

石油物探译丛 1990年第1期 60-66页

作者： steven L. roche 王宝祥

在采集和处理过程中,对地层信息反射地震数据的利用需要对数据的相位和振幅作仔细考虑。地层勘探有一种方法就是计算地质模型的地震响应。经常使用一个零相位子波并对最终得出的道的振幅和相位均作了周密检查。对地震数据与模型道相符... 详细信息

在采集和处理过程中,对地层信息反射地震数据的利用需要对数据的相位和振幅作仔细考虑。地层勘探有一种方法就是计算地质模型的地震响应。经常使用一个零相位子波并对最终得出的道的振幅和相位均作了周密检查。对地震数据与模型道相符的程度作了认真的研究。本文对采集方法以及用于得出零相位,相对振幅剖面的处理流程作了描述。振幅问题为本文要具体讨论的话题。反射相对振幅的保持是通过计算和应用一套表层一致的道标定来完成的。处理陆上数据,特别是将要叙述的可控震源数据在取得相对振幅剖面中所出现的困难颇多,包括耦合效应及震源产生的噪声。震源耦合以及接收器耦合的变化直接影响着反射数据的振幅。来自诸如地滚波及空气波等产生的干扰限制了“标定”时窗的能力,致使不能正确计及震源耦合和接收器耦合。应用地表一致标定和球面发散校正可产生一个相对振幅叠加。然而,该叠加并不必然是最佳的信噪比叠加。大的振幅,震源产生的噪声以及随机环境噪声会通过共中心点(CMP)叠加处理造成叠加剖面质量下降。 CMP相异叠加(DIVERSITY STACK)可衰减那些在CMP道集内的振幅大和时间,空间可变的干扰。在通过耦合校正标定来取得恒定的反射信号振幅后,相异叠加可被证明为接近最佳信噪比叠加的真振幅处理。

关键词：陆上地震勘探数据处理震源耦合检测器

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

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亚洲高山流域千年尺度地表剥蚀的制约因素

中国科学:地球科学 2025年第1期 75-94页

作者：杨业 steven A.BINNIE 徐胜刘丛强 Tibor J.DUNAI 天津大学地球系统科学学院表层地球系统科学研究院 Institute of Geology and Mineralogy University of Cologne

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率... 详细信息

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率变化范围从（7.4±0.7）mm ka-1（1σ;青藏高原内部）到（9,646744+777）mm ka-1（1σ;青藏高原南部）跨四个数量级,中位数为186mm ka-1.逐个像元计算的核素产率与传统模型使用质心坐标和平均高程计算的核素产率相比,后者96.6%核素产率被低估,其中高程差越大越被低估.两种方法计算的产率偏差可达40%,究其原因可能是流域高程分布不均和核素产率随海拔和纬度呈非线性变化.通过量化地表剥蚀速率与构造、气候、地形和岩性之间的相关性将有助于推演未知流域的剥蚀速率.从局部小尺度分析,亚热带台湾岛地区剥蚀速率可能主要受降水和新构造驱动的山体滑坡影响,而降水变化范围较窄的青藏高原东部的剥蚀速率主要受控于地形;冰川覆盖的高原地区剥蚀速率受冰川作用影响,如帕米尔、青藏高原内部和南部地区;青藏高原内部剥蚀速率较低是因为较低的降水和较高的侵蚀基准面,从而限制了河流的下切和地表起伏度演化.与局部小尺度强调单一主控因素不同,本研究对亚洲高山流域宏观大尺度进行量化分析发现:（1）地形指标（包括坡度、地形起伏度和河道陡峭指数）与剥蚀速率在千年尺度呈现一致的幂函数关系,而非简单线性;（2）剥蚀速率与气候（包括与海拔相关的降水、温度和植被覆盖度）和新构造活动（地震核密度分布）呈近似幂函数关系,为次要控制因素;（3）岩性与剥蚀速率没有明显的相关性,可能受限于流域复杂的岩性混合和低分辨率的可侵蚀指数数据.

关键词： 10Be剥蚀速率气候变化构造抬升地形梯度亚洲高山流域

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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

Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期 74-93页

作者： Ye YANG steven A.BINNIE Sheng XU Cong-Qiang LIU Tibor J.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

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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

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.