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Virus-Induced Gene Silencing in the Culinary Ginger （Zingiber officinale）： An Effective Mechanism for Down-Regulating Gene Expression in Tropical Monocots

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Molecular Plant 2009年第5期2卷 1084-1094页

作者： Tanya Renner Jennifer Bragg Heather E. Driscoll Juliana Cho Andrew O. Jackson Chelsea D. Specht Department of Plant and Microbial Biology University of California Berkeley CA 94720 USA Present address: Genornics and Gene Discovery USDA ARS PWA WRRC-GGD 800 Buchanan Street Albany CA 94710 USA

Virus-induced gene silencing （VIGS） has been shown to be effective for transient knockdown of gene expression in plants to analyze the effects of specific genes in development and stress-related responses. VlGS is well established for studies of model systems and crops within the Solanaceae, Brassicaceae, Leguminaceae, and Poaceae, but only recently has been applied to plants residing outside these families. Here, we have demonstrated that barley stripe mosaic virus （BSMV） can infect two species within the Zingiberaceae, and that BSMV-VIGS can be applied to specifically down-regulate phytoene desaturase in the culinary ginger Zingiber officinale. These results suggest that extension of BSMV-VlGS to monocots other than cereals has the potential for directed genetic analyses of many important temperate and tropical crop species.

关键词： Barley stripe mosaic virus virus-induced gene silencing VIGS Zingiber officinale Monocot.

Developments in 4D-printing:a review on current smart materials,technologies,and applications

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International Journal of Smart and Nano Materials 2019年第3期10卷 205-224页

作者： Zhizhou Zhang Kahraman G.Demir Grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeleyCAUSA

Recent advances in additive manufacturing(AM),commonly known as three-dimensional(3D)-printing,have allowed researchers to create complex shapes previously impossible using traditional fabrication methods.A research branch that originated from 3D-printing called four-dimensional(4D)-printing involves printing with smart materials that can respond to external stimuli.4Dprinting permits the creation of on-demand dynamically controllable shapes by integrating the dimension of *** achievements in synthetic smart materials,novel printers,deformation mechanism,and mathematical modeling have greatly expanded the feasibility of *** this paper,progress in the 4Dprinting field is reviewed with a focus on its practical *** discuss smart materials developed using 4D-printing with explanations of their morphing ***,case studies are presented on self-constructing structures,medical devices,and soft *** conclude with challenges and future opportunities in the field of 4D-printing.

关键词： 3D-printing 4D-printing smart materials multifunctional soft robotics

What do we know about parasitic plants and the leaf economic spectrum?

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Journal of Plant Ecology 2022年第4期15卷 691-699页

作者： Audrey F.Haynes Department of Integrative Biology University of California BerkeleyBerkeleyCA 94720USA

The leaf economic spectrum(LES)quantifes correlations between key leaf traits across vascular plants and distills much of the variation in these traits to a single *** LES,remarkable in its near universality,has been extensively researched across a variety of ***,parasitic plants relationship to the LES framework remains relatively *** the LES is,in part,driven by physiological tradeoffs in the acquisition of carbon(C),in theory heterotrophy in parasitic plants,which supplants some of the essential functions of leaves,could lead to departures from the *** global leaf trait data from the TRY database,this work assessed the overall representation of parasitic plants in the TRY database,then compared the LES suite of leaf traits in parasitic plants to their non-parasitic *** their unique physiology,parasitic plants did not deviate dramatically from the LES,although there were examples of differences in position on the LES and relationships among *** more importantly,parasitic plants are not well represented in the TRY database,making any conclusions here premature.

关键词： parasitic plants leaf economic spectrum TRY database leaf traits

The Séchilienne (France) Landslide:a Non-typical Progressive Failure Implying Major Risks

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Journal of Mountain Science 2011年第2期8卷 117-123页

作者： Jean-Louis DURVILLE Christophe BONNARD Pierre POTHERAT Conseil général de l'environnement et du développement durable Paris France Independent expert PBBG SA Lausanne Switzerland Centred'études techniques de l'équipement Lyon France

The National Road RN 91 has been threatened for about twenty-five years by a huge landslide, located 25 km south-east to the town of Grenoble (France). If several million cubic meters of rock fall down, the debris will dam the valley. Then the failure of the dam by overtopping and rapid erosion might result in a catastrophic flood and dramatic consequences for human life, environment and economy throughout the valley. The paper presents the hazard assessment based on geological and hydrological surveys, including small scale hydraulic tests, as well as the risk evaluation that has been performed. The risk management relies first upon a high level monitoring and an emergency plan; various mitigation strategies have been considered.

关键词： Landslide Progressive failure Séchilienne France

A hierarchical path-segmentation movement ecology framework

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Ecological Processes 2022年第1期11卷 787-801页

作者： Wayne M.Getz Department of Environmental Sciences University of CaliforniaBerkeley 94708CAUSA School of Mathematical Sciences University of KwaZulu-NatalDurbanSouth Africa

This paper lays out a hierarchical,appropriate-complexity framework for conceptualizing movement-path segments at different spatiotemporal scales in a way that facilitates comparative analyses and bridges behavior and mathematical *** then outlines a process for generating a multimode,multiscale stochastic simulation model that can be used to test animal movement hypotheses and make predictions of movement responses to management and global *** methods for analyzing movement data begin by generating step-length(SL)and turning-angle(TA)distributions from relocation time-series data,some of which are linked to ecological,landscape,and environmental *** frequency at which these data are collected may vary from sub-seconds to several *** kinds of questions that may be asked of these data,however,are very much scale *** hierarchical path-segmentation(HPS)framework presented here clarifies how the scale at which SL and TA data are collected relates to other sub-and super-diel *** arise because the information contained in SL and TA time series are often not directly relatable to the physiological,ecological,and sociological factors that drive the structure of movement paths at longer *** difficulties are overcome by anchoring the classification of movement types around the concept of fixed-period(24 h)diel activity routines and providing a bridge between behavioral/ecological and stochastic-walk concepts(means,variances,correlations,individual-state and local environmental covariates).This bridge is achieved through the generation of relatively short segments conceived as characteristic sequences of fundamental movement *** short segments are then used to characterize longer canonical-activity-mode segments that emerge through movement at behaviorally relevant sub-diel *** thus provides a novel system for integrating sub-minute movement sequences into canonical activity modes(CAMs)that,i

关键词： Hierarchical path segmentation(HPS) Fundamental movement elements(FuMEs) Canonical activity modes(CAMs) Diel activity routines(DARs) Life-history movement phases(LiMPS) Multi-CAM metaFuME Markov(M-cubed)models Biased correlated random walk models

Transport and humification of dissolved organic matter within a semi-arid floodplain

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Journal of Environmental Sciences 2017年第7期29卷 24-32页

作者： Wenming Dong Jiamin Wan Tetsu K.Tokunaga Benjamin Gilbert Kenneth H.Williams Earth and Environment Sciences Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

In order to understand the transport and humification processes of dissolved organic matter（DOM） within sediments of a semi-arid floodplain at Rifle,Colorado,fluorescence excitation–emission matrix（EEM） spectroscopy,humification index（HIX） and specific UV absorbance（SUVA） at 254 nm were applied for characterizing depth and seasonal variations of DOM *** revealed that late spring snowmelt leached relatively fresh DOM from plant residue and soil organic matter down into the deeper vadose zone（VZ）.More humified DOM is preferentially adsorbed by upper VZ sediments,while non-or lesshumified DOM was transported into the deeper ***,DOM at all depths undergoes rapid biological humification process evidenced by the products of microbial by-product-like（i.e.,tyrosine-like and tryptophan-like） matter in late spring and early summer,particularly in the deeper VZ,resulting in more humified DOM（e.g.,fulvic-acid-like and humic-acid-like substances） at the end of *** indicates that DOM transport is dominated by spring snowmelt,and DOM humification is controlled by microbial degradation,with seasonal *** is expected that these relatively simple spectroscopic measurements（e.g.,EEM spectroscopy,HIX and SUVA） applied to depth-and temporally-distributed pore-water samples can provide useful insights into transport and humification of DOM in other subsurface environments as well.

关键词： Dissolved organic matter Transport Humification Semi-arid Fluorescence excitation-emission matrix

Distributed non-cooperative robust MPC based on reduced-order models

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Control Theory and Technology 2016年第1期14卷 11-20页

作者： Yushen LONG Shuai LIU Lihua XIE Karl Henrik JOHANSSON School of Electrical and Electronic Engineering Nanyang Technological University 639798 Singapore ACCESS Linnaeus Center School of Electrical Engineering Royal Institute of Technology SE-100 44 Stockholm Sweden

In this paper, a non-cooperative distributed MPC algorithm based on reduced order model is proposed to stabilize large-scale systems. The large-scale system consists of a group of interconnected subsystems. Each subsystem can be partitioned into two parts： measurable part, whose states can be directly measured by sensors, and the unmeasurable part. In the online computation phase, only the measurable dynamics of the corresponding subsystem and neighbour-to-neighbour communication are necessary for the local controller design. Satisfaction of the state constraints and the practical stability are guaranteed while the complexity of the optimization problem is reduced. Numerical examples are given to show the effectiveness of this algorithm.

关键词： Model predictive control distributed control building energy efficiency

Heterologous Expression of the Mevalonic Acid Pathway in Cyanobacteria Enhances Endogenous Carbon Partitioning to Isoprene

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Molecular Plant 2014年第1期7卷 71-86页

作者： Fiona K. Bentley Andreas Zurbriggen Anastasios Melis Department of Plant and Microbial Biology University of California 111 Koshland Hall Berkeley CA 94720-3102 USA

Heterologous expression of the isoprene synthase gene in the cyanobacterium Synechocystis PCC 6803 conferred upon these microorganisms the property of photosynthetic isoprene （C5H8） hYdrocarbons production. Continuous production of isoprene from CO2 and H2O was achieved in the light, occurring via the endogenous methylerythritolphosphate （MEP） pathway, in tandem with the growth of Synechocystis. This work addressed the issue of photosynthetic carbon partitioning between isoprene and biomass in Synechocystis. Evidence is presented to show heterologous genomic integration and cellular expression of the mevalonic acid （MVA） pathway genes in Synechocystis endowing a non-native pathway for carbon flux amplification to isopentenyl-diphosphate （IPP） and dimethylallyl-diphosphate （DMAPP） precursors of isoprene. Heterologous expression of the isoprene synthase in combination with the MVA pathway enzymes resulted in photosynthetic isoprene yield improvement by approximately 2.5-fold, compared with that measured in cyanobacteria transformed with the isoprene synthase gene only. These results suggest that the MVA pathway introduces a bypass in the flux of endogenous cellular substrate in Synechocystis to IPP and DMAPP, overcoming flux limitations of the native MEP pathway. The work employed a novel chromosomal integration and expression of synthetic gene operons in Synechocystis, comprising up to four genes under the control of a single promoter, and expressing three operons simultaneously. This is the first time an entire biosynthetic pathway with seven recombinant enzymes has been heterologously expressed in a photosynthetic microorganism. It constitutes contribution to the genetic engineering toolkit of photosynthetic microorganisms and a paradigm in the pursuit of photosynthetic approaches for the renewable generation of high-impact products.

关键词： biofuels cyanobacteria isoprene isoprene synthase metabolic engineering photosynthesis Synechocystis.

An electronic nose using a single graphene FET and machine learning for water, methanol, and ethanol

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Microsystems & Nanoengineering 2020年第1期6卷 969-981页

作者： Takeshi Hayasaka Albert Lin Vernalyn C.Copa Lorenzo P.Lopez Jr Regine A.Loberternos Laureen Ida M.Ballesteros Yoshihiro Kubota Yumeng Liu Arnel A.Salvador Liwei Lin berkeley Sensor and Actuator Center&Department of Mechanical Engineering University of California at BerkeleyBerkeleyCA 94720USA Materials Science and Engineering Program College of ScienceUniversity of the Philippines Diliman1101 Quezon CityPhilippines National Institute of Physics College of ScienceUniversity of the Philippines Diliman1101 Quezon CityPhilippines

The poor gas selectivity problem has been a long-standing issue for miniaturized chemical-resistor gas *** electronic nose(e-nose)was proposed in the 1980s to tackle the selectivity issue,but it required top-down chemical functionalization processes to deposit multiple functional ***,we report a novel gas-sensing scheme using a single graphene field-effect transistor(GFET)and machine learning to realize gas selectivity under particular conditions by combining the unique properties of the GFET and e-nose *** of using multiple functional materials,the gas-sensing conductivity profiles of a GFET are recorded and decoupled into four distinctive physical properties and projected onto a feature space as 4D output vectors and classified to differentiated target gases by using machine-learning *** single-GFET approach coupled with trained pattern recognition algorithms was able to classify water,methanol,and ethanol vapors with high accuracy quantitatively when they were tested ***,the gas-sensing patterns of methanol were qualitatively distinguished from those of water vapor in a binary mixture condition,suggesting that the proposed scheme is capable of differentiating a gas from the realistic scenario of an ambient environment with background *** such,this work offers a new class of gas-sensing schemes using a single GFET without multiple functional materials toward miniaturized e-noses.

关键词： methanol selectivity electronic