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A novel method for clustering cellular data to improve classification

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Neural regeneration research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering

Piling up multidecker pyrgos[n]cages as antibacterial materials

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Science China Materials 2025年第1期 314-316页

作者： Miguel A.Liuzzi-Vaamonde Jackson B.Lancaster Samantha A.mason Yuanning Feng Department of Chemistry and Biochemistry The University of Oklahoma

The development of antibiotics is regarded as one of the most significant scientific advances in modern medicine. Before the commercialization of antibiotics, infectious diseases were catastrophic throughout history [1]. Penicillin was used to treat serious infections in the 1940s, but unfortunately, with the introduction of antibiotics came the emergence of antibiotic resistance [2,3]. Evolved and adapted methicillin-resistant Staphylococcus aureus (MrSA) strains are presently impacting community and healthcare systems across the globe [4].

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Sand dunes as potential sources of dust in northern China

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Science China Earth Sciences 2016年第4期59卷 760-769页

作者： Mark r SwEENEY LU HuaYu CUI MengChun Joseph A mason FENG Han XU Zhiwei Department of Earth Sciences University of South Dakota Laboratory of Earth Surface Process and Environment School of Geographic and Oceanographic Sciences Nanjing University Department of Geography University of Wisconsin-Madison

while saltation bombardment of sand grains on a fine substrate can produce considerable dust, the well-sorted nature of sand dunes tends to preclude them from consideration as major dust sources. recent research, however, has revealed that sand dunes can, in some cases, be large sources of dust. we used the PI-SwErL(Portable In-Situ wind Erosion Laboratory) to measure in the field the potential of sand dunes and other desert landforms to emit particulate matter r, Ulan Buh, and Mu Us deserts of northern China. Combined with high resolution particle size measurements of the dune sand, an assessment of sand dunes as a dust source can be made. Large active transverse dunes tend to contain little to no stored PM-10, yet they produce a low dust flux. Coppice dunes stabilized by vegetation contain appreciable PM-10 and have very high dust emission potential. There is a positive correlation between the amount of PM-10 stored in a dune and its potential dust flux. Saltation liberates loose fines stored in dunes, making them very efficient dust emitters compared to landforms such as dry lake beds and washes where dust particles are unavailable for aeolian transport due to protective crusts or sediment cohesion. In cases where large dunes do not store PM-10 yet emit dust when active, two hypotheses can be considered:(1) iron-oxide grain coatings are removed during saltation, creating dust, and(2) sand grains collide during saltation, abrading grains to create dust. Observations reveal that iron oxide coatings are present on some dune sands. PI-SwErL data suggests that low dust fluxes from dunes containing no stored dust may represent an estimate for the amount of PM-10 dust produced by removal of iron oxide coatings. These results are similar to results from dunes in the United States. In addition, PI-SwErL results suggest that dust-bearing coppice dunes, which cover vast areas of China's sandy deserts, may become major sources of dust in the f

关键词： Coppice dunes Transverse dunes Dust PI-SwErL Desert

Standardizing and Centralizing Datasets for Efficient Training of Agricultural Deep Learning Models

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Plant Phenomics 2023年第4期5卷 689-702页

作者： Amogh Joshi Dario Guevara mason Earles Department of Viticulture and Enology University of CaliforniaDavisDavisCAUSA Department of Biological and Agricultural Engineering University of CaliforniaDavisDavisCAUSA AI Institute for Next-Generation Food Systems(AIFS) University of CaliforniaDavisDavisCAUSA

In recent years,deep learning models have become the standard for agricultural computer *** models are typically fine-tuned to agricultural tasks using model weights that were originally fit to more general,non-agricultural *** lack of agriculture-specific fine-tuning potentially increases training time and resource use,and decreases model performance,leading to an overall decrease in data *** overcome this limitation,we collect a wide range of existing public datasets for 3 distinct tasks,standardize them,and construct standard training and evaluation pipelines,providing us with a set of benchmarks and pretrained *** then conduct a number of experiments using methods that are commonly used in deep learning tasks but unexplored in their domain-specific applications for *** experiments guide us in developing a number of approaches to improve data efficiency when training agricultural deep learning models,without large-scale modifications to existing *** results demonstrate that even slight training modifications,such as using agricultural pretrained model weights,or adopting specific spatial augmentations into data processing pipelines,can considerably boost model performance and result in shorter convergence time,saving training ***,we find that even models trained on low-quality annotations can produce comparable levels of performance to their high-quality equivalents,suggesting that datasets with poor annotations can still be used for training,expanding the pool of currently available *** methods are broadly applicable throughout agricultural deep learning and present high potential for substantial data efficiency improvements.

关键词： weights overcome shorter

The Origin of Spots in Contact Aureoles and Over-Heating of Country rock Next to a Dyke

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Journal of Earth Science 2018年第5期29卷 1005-1009页

作者： roger mason rong Liu School of Earth Sciences China University of Geosciences

Petrographic comparison of andalusite in the contact aureole of the Fangshan pluton, Zhoukoudian, Beijing, China, and hornfels in the aureole of the Markfield diorite, Leicestershire, Eng- land, shows that spots characteristic of the outer zones of contact metamorphic aureoles did not form during the progressive stage of contact metamorphism, but are pseudomorphs after earlier andalusite with characteristic chiastolite microstructure. The baked margin produced by contact metamorphism of syenite against a dyke in the Houshihushan ring complex, Shanhaiguan, Hebei Province, China, is an unusual feature caused by the dyke＇s role as a feeder to a family of cone-sheets.

关键词： contact metamorphism contact aureole retrogression hornfels spots Zhoukoudian Houshihushan.

Poetry Translation Depends on the Translator’s Purpose:An Interview with Ian mason about Poetry Translation and Translation Studies

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Comparative Literature:East & west 2011年第1期 146-154页

作者： Ian mason Heriot-watt University

本文针对诗歌翻译及中西翻译研究的一些问题,对英国翻译研究学者伊恩·梅森进行了访谈。梅森教授据自己的研究角度,指出诗歌翻译取决于译者目的,同时对于诗歌翻译的未来表示了深切的担忧;对于西方翻译研究的成就与现状做了中肯而客观的... 详细信息

本文针对诗歌翻译及中西翻译研究的一些问题,对英国翻译研究学者伊恩·梅森进行了访谈。梅森教授据自己的研究角度,指出诗歌翻译取决于译者目的,同时对于诗歌翻译的未来表示了深切的担忧;对于西方翻译研究的成就与现状做了中肯而客观的评述。这次访谈既讨论了不同视角导致的对诗歌翻译的不同理解,也显示出西方学者对待学术问题的严谨与坦率。

关键词：诗歌翻译翻译研究访谈梅森研究角度不同视角西方学者学术问题译者英国

Optically stimulated luminescence dating of aeolian sand in the Otindag dune field and Holocene climate change

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Science China Earth Sciences 2008年第6期51卷 837-847页

作者： Joseph mason James SwINEHArT ronald GOBLE Department of Geography University of Wisconsin Madison School of Natural resources IANR University of Nebraska-Lincoln Department of Geosciences University of Nebraska-Lincoln

The dune system in Otindag sand field of northern China is sensitive to climate change, where effective moisture and related vegetation cover play a controlling role for dune activity and stability. Therefore, aeolian deposits may be an archive of past environmental changes, possibly at the millennial scale, but previous studies on this topic have rarely been reported. In this study, thirty-five optically stimulated luminescence (OSL) ages of ten representative sand-paleosol profiles in Otindag sand field are ob-tained, and these ages provide a relatively complete and well-dated chronology for.wet and dry varia-tions in Holocene. The results indicate that widespread dune mobilization occurred from 9.9 to 8.2 ka, suggesting a dry early Holocene climate. The dunes were mainly stabilized between 8.0 and 2.7 ka, implying a relatively wet climate, although there were short-term penetrations of dune activity during this wet period. After ~2.3 ka, the region became dry again, as inferred from widespread dune activity. The '8.2 ka' cold event and the Little Ice Age climatic deterioration are detected on the basis of the dune records and OSL ages. During the Medieval warm Period and the Sui-Tang warm Period (570-770 AD), climate in Otindag sand field was relatively humid and the vegetation was denser, and the sand dunes were stabilized again. These aeolian records may indicate climate changes at millennial time scale during Holocene, and these climatic changes may be the teleconnection to the climate changes elsewhere in the world.

关键词： Otindag sand field OSL dating Holocene drought dune

Dissecting the Native Architecture and Dynamics of Cyanobacterial Photosynthetic Machinery

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Molecular Plant 2017年第11期10卷 1434-1448页

作者： Selene Casella Fang Huang David mason Guo-Yan Zhao Giles N. Johnson Conrad w. Mullineaux Lu-Ning Liu Institute of Integrative Biology University of Liverpool Crown Street Liverpool L69 7ZB UK Centre for Cell Imaging University of Liverpool Crown Street Liverpool L69 7ZB UK College of Life Science Shandong Normal University Jinan 250014 P. R. China School of Earth and Environmental Sciences University of Manchester Oxford Road Manchester M13 9PT UK School of Biological and Chemical Sciences Queen Mary University of London Mile End Road London E1 4NS UK

The structural dynamics and flexibility of cell membranes play fundamental roles in the functions of the cells, i.e., signaling, energy transduction, and physiological adaptation. The cyanobacterial thylakoid membrane represents a model membrane that can conduct both oxygenic photosynthesis and respiration simultaneously. In this study, we conducted direct visualization of the global organization and mobility of photosynthetic complexes in thylakoid membranes from a model cyanobacterium, Synechococcus elongatus PCC 7942, using high-resolution atomic force, confocal, and total internal reflection fluorescence microscopy. we visualized the native arrangement and dense packing of photosystem I （PSI）, photosystem II （PSlI）, and cytochrome （Cyt） befwithin thylakoid membranes at the molecular level. Furthermore, we func- tionally tagged PSI, PSlI, Cyt bef, and ATP synthase individually with fluorescent proteins, and revealed the heterogeneous distribution of these four photosynthetic complexes and determined their dynamic features within the cr.wding membrane environment using live-cell fluorescence imaging. we characterized red light-induced clustering localization and adjustable diffusion of photosynthetic complexes in thylakoid membranes, representative of the reorganization of photosynthetic apparatus in response to environmental changes. Understanding the organization and dynamics of photosynthetic membranes is essential for rational design and construction of artificial photosynthetic systems to undarpin bioenergy development. Knowledge of cyanobacterial thylakoid membranes could also be extended to other cell membranes, such as chloroplast and mitochondrial membranes.

关键词： cyanobacteria thylakoid membrane atomic force microscopy photosynthesis fluorescence imaging protein dynamics

Field scanner design for MUSTANG of the Green Bank Telescope

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2091-2096页

作者： CHENG JingQuan LI Yang LI XinNan mason Brian National radio Astronomy Observatory Charlottesville 22903 USA Nanjing Institute of Astronomical Optics and Technology Nanjing 210042 China

MUSTANG (Multiplex SQUID TES Array at Ninety GHz) is a bolometer camera for the Green Bank Telescope (GBT) working at a frequency of 90 *** detector has a field of view of 40 *** cancel out random emission change from atmosphere and other sources,requires a fast scanning reflecting system with a few arcminute *** this paper,the aberrations of an off-axis system are *** condition for an optimized system is *** an optimized system,as additional image transfer mirrors are introduced,new aberrations of the off-axis system may be reintroduced,resulting in a limited field of *** this paper,different scanning mirror arrangements for the GBT system are analyzed through the ray tracing *** include using the subreflector as the scanning mirror,chopping a flat mirror and transferring image with an ellipse mirror,and chopping a flat mirror and transferring image with a pair of face-to-face paraboloid *** system analysis shows that chopping a flat mirror and using a well aligned pair of paraboloids can generate the required field of view for the MUSTANG detector system,while other systems all suffer from larger off-axis aberrations added by the system *** spot diagrams of the well aligned pair of paraboloids produced are only about one Airy disk size within a scanning angle of about 3 arcmin.

关键词： antenna optics off-axis linear astigmatism coma reflector scanner