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Functional specialization of Nicotiana attenuata phytochromes in leaf development and flowering time

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Journal of Integrative Plant Biology 2017年第3期59卷 205-224页

作者： Variluska Fragoso Youngjoo Oh Sang-Gyu Kim Klaus Gase Ian Thomas baldwin department of Molecular Ecology Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 D-07745 .lena Germany Center for Genome Engineering，Institute of Basic Science，daejeon，South Korea

Phytochromes mainly function in photoau- totrophic organisms to adjust growth in response to fluctuating light signals. The different isoforms of plant phytochromes often display both conserved and divergent roles, presumably to fine-tune plant responses to environmental signals and optimize fitness. Here we describe the distinct, yet partially redundant, roles of phytochromes NaPHYA, NaPHYB1 and NaPHYB2 in a wild tobacco species, Nicotiana attenuata using RNAi-silenced phytochrome lines. Consistent with results reported from other species, silencing the expression of NaPHYA or NaPHYB2 in N. attenuata had mild or no influence on plant develop- ment as long as NaPHYBI was functional; whereas silencing the expression of NaPHYB1 alone strongly altered flowering time and leaf morphology. Thecontribution of NaPHYB2 became significant only in the absence of NaPHYB1; plants silenced for both NaPHYB1 and NaPHYB2 largely skipped the rosette- stage of growth to rapidly produce long, slender stalks that bore flowers early： hallmarks of the shade- avoidance responses. The phenotyping of phyto- chrome-silenced lines, combined with sequence and transcript accumulation independent functional analysis, suggest the diversification of the phytochromes, and a dominant role of NaPHYB1 and NaPHYB2 in N. attenuata＇s vegetative and reproductive development.

关键词： James L. Weller University of Tasmania Australia

MR-GUIdEd PULSE OXIMETRY IMAGING OF BREAST IN VIVO

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 199-208页

作者： ZHIQIU LI SHUdONG JIANG VENKATARAMANAN KRISHNASWAMY SCOTT CdAVIS SUBHAdRA SRINIVASAN keith d.PAULSEN BRIAN W.POGUE Thayer School of Engineering Dartmouth College Hanover NH 03755USA

A near-infrared(NIR)tomography system with spectrally-encoded sources in two wavelength bands was built to quantify the temporal oxyhemoglobin and deoxyhemoglobin contrast in breast tissue at a 20 Hz *** system was integrated into a 3T magnetic resonance(MR)imaging system through a customized breast coil interface for simultaneous optical and MRI *** this configuration,the MR images provide breast tissue structural information for NIR spectroscopy of adipose andfibro-glandular tissue in *** characterization performance of the NIR system was verified through dynamic phantom *** human subjects were imaged withfinger pulse oximeter(PO)plethysmogram synchronized to the NIR system to provide a frequency-locked *** the raw data from the NIR system and the recovered absorption coefficients of the breast at two wavelengths showed the same frequency of about 1.3 Hz as the PO *** frequency lock-in approach provided a practical platform for MR-localized recovery of small pulsatile variations of oxyhemoglobin and deoxyhemoglobin in the breast,which are related to the heartbeat and vascular resistance of the tissue.

关键词： High frame-rate fast imaging MR-guided near-infrared tomography breast hemodynamics

Circadian clock component, LHY, tells a plant when to respond photosynthetically to light in nature

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Journal of Integrative Plant Biology 2017年第8期59卷 572-587页

作者： Youngsung Joo Variluska Fragoso Felipe Yon Ian T. baldwin Sang-Gyu Kim department of Molecular Ecology Max Planck Institute for Chemical EcologyHans-Knoll-Straβe 8D-07745 JenaGermany center for genome engineering institute for basic scienceYuseong-guDaejeon34047South Korea

The circadian clock is known to increase plant growth and fitness, and is thought to prepare plants for photosynthesis at dawn and dusk; whether this happens in nature was unknown. We transformed the native tobacco, Nicotiana attenuata to silence two core clock components, NaLHY （irLHY） and NaTOC1 （irTOC1）. We characterized growth and light- and dark-adapted photosynthetic rates （Ac） throughout a 24 h clay in empty vector-transformed （EV）, irLHY, and irTOC1 plants in the field, and in NaPhyA-and NaPhyB1-silenced plants in the glasshouse. The growth rates of irLHY plants were lower than those of EV plants in the field. While irLHY plants reduced Ac earlier at dusk, no differences between irLHY and EV plants were observed at dawn in the field, irLHY, but not EV plants, responded to light in the night by rapidly increasing Ac. Under controlled conditions, EV plants rapidly increased Ac in the day compared to dark-adapted plants at night; irLHY plants lost these time-dependent responses. The role of NaLHY in gating photosynthesis is independent of the light-depen- dent reactions and red light perceived by NaPhyA, but not NaPhyB1. In summary, the circadian clock allows plants not to respond photosynthetically to light at night by anticipating and gating red light-mediated in native tobacco.

关键词： in et is of Circadian clock component,LHY,tells a plant when to respond photosynthetically to light in nature were for Figure EV TOC

Fitness consequences of a clock pollinator filter in Nicotiana attenuata flowers in nature

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Journal of Integrative Plant Biology 2017年第11期59卷 805-809页

作者： felipe yon danny kessler youngsung joo sang-gyu kim ian t.baldwin department of molecular ecology max planck institute for chemical ecologyHans-Knoll-StraBe 8D-07745 JenaGermany center for genome engineering institute for basic scienceYuseong-gu34047 DaejeonSouth Korea

Nicotiana attenuata flowers, diurnally open,emit scents and move vertically to interact with nocturnal hawkmoth and day-active hummingbird pollinators. To examine the fitness consequences of these floral rhythms, we conducted pollination trials in the plant’s native habitat with phase-shifted flowers of plants silenced in circadian clock genes. The results revealed that some pollination benefits observed under glasshouse conditions were not reproduced under natural field conditions. Floral arrhythmicity increased pollination success by hummingbirds, while reducing those by hawkmoths in the field. Thus, floral circadian rhythms may influence a plant’s fitness by filtering pollinators leading to altered seed set from outcrossed pollen.

关键词： Fitness consequences a clock pollinator filter in Niicotiana attenuata flowers in nature

Connexins in neurons and glia: targets for intervention in disease and injury

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Neural Regeneration Research 2015年第7期10卷 1013-1017页

作者： keith B.Moore John O'Brien Richard S.Ruiz M.D.Department of Ophthalmology & Visual Science The University of Texas Health Science Center at Houston The University of Texas Graduate School of Biomedical Sciences

Both neurons and glia throughout the central nervous system are organized into networks by gap junctions. Among glia, gap junctions facilitate metabolic homeostasis and intercellular communication. Among neurons, gap junctions form electrical synapses that function primarily for communication. However, in neurodegenerative states due to disease or injury gap junctions may be detrimental to survival. Electrical synapses may facilitate hyperactivity and bystander killing among neurons, while gap junction hemichannels in glia may facilitate inflammatory signaling and scar formation. Advances in understanding mechanisms of plasticity of electrical synapses and development of molecular therapeutics to target glial gap junctions and hemichannels offer new hope to pharmacologically limit neuronal degeneration and enhance recovery.

关键词： ischemia retinal degeneration amacrine cells astrocytes dopamine receptors adenosine receptors NMdA receptors connexin mimetic peptides

Liquid deposition photolithography for submicrometer resolution three-dimensional index structuring with large throughput

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Light(Science & Applications) 2013年第1期2卷 209-214页

作者： Adam C Urness Eric d Moore keith K Kamysiak Michael C Cole Robert R McLeod department of Electrical Engineering University of Colorado at BoulderBoulderCO 80309USA.

Photonic devices increasingly require three-dimensional control of refractive index,but existing fabrication methods such as femtosecond micromachining,multilayer lithography and bulk diffusion can only address a select scale range,are often limited in complexity or thickness and have low *** introduce a new fabrication method and polymeric material that can efficiently create mm^(3) optical devices with programmable,gradient index of refraction with arbitrary feature *** contrast of 0.1 is demonstrated,which is 100 times larger than femtosecond micromachining,and 20 times larger than commercial holographic *** is achieved by repetitive microfluidic layering of a self-developing photopolymer structured by projection *** process has the unusual property that total fabrication time for a fixed thickness decreases with the number of layers,enabling fabrication 10^(5) faster than femtosecond *** demonstrate the process by sequentially writing 100 layers to fabricate a mm thick waveguide array.

关键词： holographic photopolymers lithography photonic device fabrication single photon polymerization three-dimensional structuring

RISK REdUCTION IN A PROJECT PORTFOLIO

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Journal of Systems Science and Systems Engineering 2017年第1期26卷 3-22页

作者： dujuan Guan Peng Guo keith W. Hipel Liping Fang School of Management Northwestern Polytechnical University Xi 'an 710072 China department of Management Hefei University Hefei 230601 China department of Systems design Engineering University of Waterloo Waterloo Ontario Canada N2L 3G1 Centre for International Governance Innovation Waterloo Ontario Canada N2L 6C2 department of Mechanical and Industrial Engineering Ryerson University Toronto Ontario Canada M5B 2K3

The positive impacts of managing projects as a portfolio are quantified by comparing the value of the integrated risk of a project portfolio and the aggregation of single project risks implemented separately. Firstly, the integrated risk is defined by proposing risky events based on set theory. Secondly, as projects interact with each other in a project portfolio, the integrated risk is evaluated by using a Bayesian network structure learning algorithm to construct an interdependent network of risks. Finally, the integrated risk of a practical case is assessed using this method, and the results show that the proposed method is an effective tool for calculating the extent of risk reduction of implementing a project portfolio and identifying the most risky project, so as to assist companies in making comprehensive decisions in the phase of portfolio selection and portfolio controlling.

关键词： Project portfolio integrated risk set theory Bayesian network risk assessment

Fitness consequences of altering floral circadian oscillations for Nicotiana attenuata

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Journal of Integrative Plant Biology 2017年第3期59卷 180-189页

作者： Felipe Yon danny Kessler Youngsung Joo Lucas Cortes Llorca Sang-Gyu Kim Ian T. baldwin department of Molecular Ecology Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 D-07745 Jena Germany Center for Genome Engineering Institute for Basic Science Yuseong-gu 34047 Daeieon South Korea

Ecological interactions between flowers and pollinators are all about timing. Flower opening/closing and scent emissions are largely synchronized with pollinator activity, and a circadian clock regulates these rhythms. However, whether the circadian clock increases a plant＇s reproductive success by regulating these floral rhythms remains untested. Flowers of Nicotiana attenuata, a wild tobacco, diurnally and rhythmically open, emit scent and move vertically through a 140° arc to interact with nocturnal hawkmoths. We tethered flowers to evaluate the importanceof flower positions for Manduca flower position dramatically sexta-mediated pollinations; nfluenced pollination. We examined the pollination success of phase-shifted flowers, silenced in circadian clock genes, NaZTL, NaLHY, and NaTOCI, by RNAi. Circadian rhythms in N. attenuata flowers are responsible for altered seed set from outcrossed pollen.

关键词： Yonggen Lou Zhejiang University China

COMPARISON OF THE ANALYTIC NETWORK PROCESS ANd THE GRAPH MOdEL FOR CONFLICT RESOLUTION

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Journal of Systems Science and Systems Engineering 2005年第3期14卷 308-325页

作者： Xin SU Ye CHEN keith W. HIPEL d. Marc KILGOUR department of Systems design Engineering University of Waterloo. Waterloo Ontario N2L3G1 Canada department of Mathematics Wilfrid Laurier University Waterloo Ontario N2L3C5 Canada

A comparison of two decision analysis tools for the analysis of strategic conflicts, the Analytic Network Process （ANP） and the graph model for conflict resolution, is carried out by applying them to the China-US TV dumping conflict. Firstly, the graph model is introduced along with practical procedures for modeling and analyzing conflicts using the decision support software, GMCR Ⅱ. Next, ANP is explained, emphasizing structural features and procedures for synthesizing priorities. Then a framework for employing ANP to analyze strategic conflicts is designed and used to compare ANP to the graph model. The case study of the China-US TV dumping conflict provides a basis for the graph model and ANP to be compared; different features of the approaches are highlighted. The study shows that because of different theoretical backgrounds, ANP and the graph model for conflict analysis both provide useful information which can be combined to furnish a better understanding of a strategic conflict.

关键词： Strategic conflict graph model for conflict resolution Analytic Network Process decision support system China-US TV dumping conflict