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Single Molecule Analysis of the Arabidopsis FRA1 Kinesin Shows that It Is a Functional Motor Protein with Unusually High Processivity

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Molecular Plant 2011年第5期4卷 879-885页

作者： Chuanmei Zhu Ram Dixit Biology Department Washington University St Louis MO 63130 USA

The Arabidopsis FRA1 kinesin contributes to the organization of cellulose microfibrils through an unknown mechanism. The cortical localization of this kinesin during interphase raises the possibility that it transports cell wallrelated cargoes along cortical microtubules that either directly or indirectly influence cellulose microfibril patterning. To determine whether FRA1 is an authentic motor protein, we combined bulk biochemical assays and single molecule fluorescence imaging to analyze the motor properties of recombinant, GFP-tagged FRA1 containing the motor and coiled-coil domains （designated as FRAI（707）-GFP）. We found that FRAI（707）-GFP binds to microtubules in an ATP-dependent manner and that its ATPase activity is dramatically stimulated by the presence of microtubules. Using single molecule studies, we found that FRAI（707）-GFP moves processively along microtubule tracks at a velocity of about 0.4 μm s-1. In addition, we found that FRAI（707）-GFP is a microtubule plus-end-directed motor and that it moves along microtubules as a dimer. Interestingly, our single molecule analysis shows that the processivity of FRAI（707）-GFP is at least twice the processivity of conventional kinesin, making FRA1 the most processive kinesin to date. Together, our data show that FRA1 is a bona fide motor protein that has the potential to drive Iong-distance transport of cargo along cortical microtubules.

关键词： Kinesin FRA1 cortical microtubule single molecule cellulose Arabidopsis.

The hyperpycnite problem

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Journal of Palaeogeography 2018年第3期7卷 197-238页

作者： G.Shanmugam Department of Earth and Environmental Sciences The University of Texas at Arlington

Sedimentologic, oceanographic, and hydraulic engineering publications on hyperpycnal flows claim that （1） river flows transform into turbidity currents at plunge points near the shoreline, （2） hyperpycnal flows have the power to erode the seafloor and cause submarine canyons, and, （3） hyperpycnal flows are efficient in transporting sand across the shelf and can deliver sediments into the deep sea for developing submarine fans. Importantly, these claims do have economic implications for the petroleum industry for predicting sandy reservoirs in deep-water petroleum exploration. However, these claims are based strictly on experimental or theoretical basis, without the supporting empirical data from modern depositional systems. Therefore, the primary purpose of this article is to rigorously evaluate the merits of these claims. A global evaluation of density plumes, based on 26 case studies （e.g., Yellow River, Yangtze River, Copper River, Hugli River （Ganges）, Guadalquivir River, Rio de ]a Plata Estuary, Zambezi River, among others）, suggests a complex variability in nature. Real-world examples show that density plumes （1） occur in six different environments （i.e., marine, lacustrine, estuarine, lagoon, bay, and reef）; （2） are composed of six different compositional materials （e.g., siliciclastic, calciclastic, planktonic, etc.）; （3） derive material from 11 different sources （e.g., river flood, tidal estuary, subglacial, etc.）; （4） are subjected to 15 different external controls （e.g., tidal shear fronts, ocean currents, cyclones, tsunamis, etc.）; and, （5） exhibit 24 configurations （e.g., lobate, coalescing, linear, swirly, U-Turn, anastomosing, etc.）. Major problem areas are：（1） There are at least 16 types of hyperpycnal flows （e.g., density flow, underflow, high-density hyperpycnal plume, high-turbid mass flow, tide-modulated hyperpycnal flow, cyclone-induced hyperpycnal turbidity current, multi-layer hyperpycnal flows, etc.）, without an underpinning principle of flu

关键词： Density plumes Facies model Hyperpycnites Submarine fans Tidal shear fronts Ocean currents Turbiditycurrents Yellow River Yangtze River

Free-Trade Agreements in a Model of Trade, Migration and Politics

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2018年第1期13卷 15-31页

作者： John Douglas Wilson Ilkay Yilmaz Department of Economics Michigan State University East Lansing M1 48824 USA Department of Economics Mersin University Ciftlikkoy Yenisehir 33342 Mersin Turkey

This paper uses a probabilistic voting model to investigate voting for a free-trade agreement between a labor-abundant country and a capital-abundant country. Migration from the labor-abundant country to the capital-abundant country increases the probability of a free-trade agreement, with lower migration costs leading to more migration and a higher free-trade probability. On the other hand, if a lower probability of free trade is caused by an increased voter bias against free-trade candidates, then there is less migration. A dynamic extension of the model is also investigated.

关键词： free trade migration Heckscher-Ohlin labor-abundant capital-abundant

Understanding Spatial Genome Organization:Methods and Insights

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Genomics, Proteomics & Bioinformatics 2016年第1期14卷 7-20页

作者： Vijay Ramani Jay Shendure Zhijun Duan Department of Genome Sciences University of WashingtonSeattleWA 98195USA Institute for Stem Cell and Regenerative Medicine University of WashingtonSeattleWA 98109USA Division of Hematology University of WashingtonSeattleWA 98195USA Department of Medicine University of WashingtonSeattleWA 98195USA Howard Hughes Medical Institute SeattleWA 98195USA

The manner by which eukaryotic genomes are packaged into nuclei while maintaining crucial nuclear functions remains one of the fundamental mysteries in biology. Over the last ten years, we have witnessed rapid advances in both microscopic and nucleic acid-based approaches to map genome architecture, and the application of these approaches to the dissection of higher- order chromosomal structures has yielded much new information. It is becoming increasingly clear, for example, that interphase chromosomes form stable, multilevel hierarchical structures. Among them, self-associating domains like so-called topologically associating domains （TADs） appear to be building blocks for large-scale genomic organization. This review describes features of these broadly-defined hierarchical structures, insights into the mechanisms underlying their formation, our current understanding of how interactions in the nuclear space are linked to gene regulation, and important future directions for the field.

关键词： Chromatin ChromosomeEpigenomics 4D nucleomeHi-C

Myosin *** Regulates Protonemal Patterning and Developmental Timing in the Moss Physcomitrella patens

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Molecular Plant 2011年第5期4卷 909-921页

作者： Shu-Zon Wu Julie A. Ritchie Ai-Hong Pan Ralph S. Quatrano Magdalena Bezanilla Department of Biology University of Massachusetts Amherst MA 01003 USA Department of Biology Washington University in St Louis St Louis MO 63130 USA

Plants have two classes of myosins. While recent work has focused on class XI myosins showing that myosin XI is responsible for organelle motility and cytoplasmic streaming, much less is known about the role of myosin VIII in plant growth and development. We have used a combination of RNAi and insertional knockouts to probe myosin VIII function in the moss Physcomitrella patens. We isolated Amyo8ABCDE plants demonstrating that myosin VIII is not required for plant viability. However, myosin VIII mutants are smaller than wild-type plants in part due to a defect in cell size. Additionally, Amyo8ABCDE plants produce more side branches and form gametophores much earlier than wild-type plants. In the ab- sence of nutrient media, Amyo8ABCDE plants exhibit significant protonemal patterning defects, including highly curved protonemal filaments, morphologically defective side branches, as well as an increase in the number of branches. Exogenous auxin partially rescues protonemal defects in Amyo8ABCDE plants grown in the absence of nutrients. This result, together with defects in protonemal branching, smaller caulonemal ceils, and accelerated development in the Amyo8ABCDE plants, suggests that myosin VIII is involved in hormone homeostasis in P patens.

关键词： Cell division cell expansion cell morphogenesis cytoskeleton development.

IFRS adoption in China and foreign institutional investments

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China Journal of Accounting Research 2019年第1期12卷 1-32页

作者： Mark DeFond Xinzi Gao Oliver Zhen Li Lijun Xia university of Southern California Sun Yat-Sen university Shanghai Lixin university of Accounting and Finance Shanghai Jiao Tong university

We examine the effectiveness of China’s IFRS adoption from the perspective of an important set of financial report users, foreign institutional investors. We find that foreign institutional investment does not increase after China’s IFRS adoption, and some evidence that it actually declines, particularly among firms with weaker incentives to credibly implement IFRS, or with greater ability to manipulate IFRS’s fair value provisions. We also find that the association between earnings and returns generally declines after IFRS adoption, consistent with reduced earnings quality. In addition, we find that foreign institutional investors’ returns decrease after China’s IFRS adoption. Finally, the decline in foreign institutional investment is greater among investors from countries with weak institutions that have also adopted IFRS. Taken together, our evidence suggests that the weak institutional infrastructure in China’s transitional economy impairs IFRS’s intended goal of attracting institutional investment through improved financial reporting quality. Further, financial information users’ home country institutions and IFRS adoption experience affect the effectiveness of IFRS adoption.

关键词： IFRS Foreign institutional investment Institutions China

Forecasting of in situ electron energy loss spectroscopy

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npj Computational Materials 2022年第1期8卷 2400-2408页

作者： Nicholas R.Lewis Yicheng Jin Xiuyu Tang Vidit Shah Christina Doty Bethany E.Matthews Sarah Akers Steven R.Spurgeon Department of Chemical Engineering University of WashingtonSeattleWA98195USA National Security Directorate Pacific Northwest National LaboratoryRichlandWA99352USA Energy and Environment Directorate Pacific Northwest National LaboratoryRichlandWA99352USA Department of Physics University of WashingtonSeattleWA98195USA

Forecasting models are a central part of many control systems,where high-consequence decisions must be made on long latency control *** models are particularly relevant for emerging artificial intelligence(AI)-guided instrumentation,in which prescriptive knowledge is needed to guide autonomous *** we describe the implementation of a long short-term memory model(LSTM)for forecasting in situ electron energy loss spectroscopy(EELS)data,one of the richest analytical probes of materials and chemical *** describe key considerations for data collection,preprocessing,training,validation,and benchmarking,showing how this approach can yield powerful predictive insight into order-disorder phase ***,we comment on how such a model may integrate with emerging AI-guided instrumentation for powerful high-speed experimentation.

关键词： consequence autonomous transitions

Acute liver failure secondary to acute antibody mediated rejection after compatible liver transplant: A case report

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World Journal of Hepatology 2022年第1期14卷 287-294页

作者： Todd J Robinson James B Hendele Idoia Gimferrer Nicolae Leca Scott W Biggins Jorge D Reyes Lena Sibulesky Department of Surgery Virginia MasonSeattleWA 98101United States Department of Surgery University of Washington Medical CenterSeattleWA 98195United States Bloodworks Northwest SeattleWA 98104United States Department of Nephrology University of Washington Medical CenterSeattleWA 98195United States Department of Gastroenterology and Hepatology University of Washington Medical CenterSeattleWA 98195United States

BACKGROUND The liver has traditionally been regarded as resistant to antibody-mediated rejection(AMR).AMR in liver transplants is a field in its infancy compared to kidney and lung *** our case we present a patient with alpha-1-antitrypsin disease who underwent ABO compatible liver transplant complicated by acute liver failure(ALF)with evidence of antibody mediated rejection on allograft biopsy and elevated serum donor-specific antibodies(DSA).This case highlights the need for further investigations and heightened awareness for timely *** SUMMARY A 56 year-old woman with alpha-1-antitrypsin disease underwent ABO compatible liver transplant from a deceased *** recipient MELD at the time of transplant was *** flow cytometric crossmatches were noted to be positive for T and B *** patient had an uneventful recovery *** on postoperative day 5 the patient developed fevers,elevated liver function tests,distributive shock,renal failure,and hepatic *** went into ALF with evidence of antibody mediated rejection with portal inflammation,bile duct injury,endothelitis,and extensive centrizonal necrosis,and C4d staining on allograft biopsy and elevated *** various interventions including plasmapheresis and immunomodulating therapy,she continued to *** was relisted and successfully underwent liver *** This very rare case highlights AMR as the cause of ALF following liver transplant requiring retransplantation.

关键词： Liver transplant Acute antibody mediated rejection Acute liver failure Donor specific antibody Liver rejection Case report

Design and analysis of extended depth of focus metalenses for achromatic computational imaging

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Photonics Research 2020年第10期8卷 1613-1623页

作者： LUOCHENG HUANA JAMES WHITEHEAD SHANE COLBURN ARKA MAJUMDAR Department of Electrical and Computer Engineering Urniversity of WashingtonSeattleWashington 98195USA Department of Physics University of WashingtonSeatteWashington 98195USA

Metasurface optics have demonstrated vast potential for implementing traditional optical components in an ultracompact and lightweight form ***,however,suffer from severe chromatic aberrations,posing serious limitations on their practical *** approaches for circumventing this involving dispersion engineering are limited to small apertures and often entail multiple scatterers per unit cell with small feature ***,we prescnt an alternative technique to mitigatc chromatic aberration and demonstrate high-quality,full-color imaging using extended depth of focus(EDOF)metalenses and computational *** EDOF metalenses have relied on cubic phase masks,where the image quality suffers from asymmetric *** we demonstrate the use of rotationally symmetric masks,including logarithmic-aspherical,and shifted axicon masks,to mitigate this *** work will inspire further development in achromatic metalenses beyond dispersion engineering and hybrid optical-digital metasurface systems.

关键词： chromatic dispersion optics