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rAL Effectors Drive Transcription Bidirectionally in Plants

Molecular Plant 2017年第2期10卷 285-296页

作者： Li Wang Fabio C. Rinaldi Pallavi Singh Erin L. doyle Zoe E. Dubrow Tuan Tu Tran Alvaro L. Perez-Quintero Boris Szurek Adam j. Bogdanove Plant Pathology and Plant-Microbe Biology Section School of Integrative Plant Science Cornell University 334 Plant Science Building Ithaca NY 14853 USA Department of Biology Doane University 1014 Boswell Avenue Crete NE 68333 USA UMR Interactions-Plantes-Microorganismes-Environnement IRD-Cirad-Universite Montpellier Montpellier France

TAL effectors delivered by phytopathogenic Xanthomonas species are DNA-sequence-specific transcrip- tional activators of host susceptibility genes and sometimes resistance genes. The modularity of DNA recognition by TAL effectors makes them important also as tools for gene targeting and genome editing. Effector binding elements （EBEs） recognized by native TAL effectors in plants have been identified only on the forward strand of target promoters. Here, we demonstrate that TAL effectors can drive plant tran- scription from EBEs on either strand and in both directions. Furthermore, we show that a native TAL effector from Xanthomonas oryzae pv. oryzicola drives expression of a target with an EBE on each strand of its promoter. By inserting that promoter and derivatives between two reporter genes oriented head to head, we show that the TAL effector drives expression from either EBE in the respective orientations, and that activity at the reverse-strand EBE also potentiates forward transcription driven by activity at the forward-strand EBE. Our results reveal new modes of action for TAL effectors, suggesting the possibility of yet unrecognized targets important in plant disease, expanding the search space for off-targets of custom TAL effectors, and highlighting the potential of TAL effectors for probing fundamental aspects of plant transcription.

关键词： xanthomonas transcription activator-like effector bidirectional reporter enhancer element off-target

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Silvicultural alternatives to conventional even-aged forest man-agement-what limits global adoption?

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Forest Ecosystems 2015年第2期2卷 123-138页

作者： Klaus j Puettmann Scott McG Wilson Susan C Baker Pablo j Donoso Lars Dr?ssler Girma Amente Brian D Harvey Thomas Knoke Yuanchang Lu Susanna Nocentini francis E Putz Toshiya Yoshida jürgen Bauhus Department of Forest Ecosystems and Society Oregon State University Consultant Forester and Forest Ecologist School ofBiological Sciences University of Tasmania Department of Forests and Society Faculty of Forest Sciences and Natural Resources Universidad Austral de Chile Southern Swedish Forest Research Centre Swedish Agricultural University Haramaya University Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue 445 Boulevard de l’Université Institute of Forest Management TUMSchool of Life Sciences Weihenstephan Technische Universit?t München Department of Forest Management and Statistics IFRIT Chinese Academy of Forestry Department of Agricultural Food and Forestry Systems University of Florence Department of Biology University of Florida Uryu Experimental Forest Field Science Center for Northern Biosphere Hokkaido University Chair of Silviculture Faculty of Environment and Natural Resources University of FreiburgTennenbacherstr

Background： The development of forestry as a scientific and management discipline over the last two centuries has mainly emphasized intensive management operations focused on increased commodity production, mostly wood. This conventionar＇ forest management approach has typically favored production of even-aged, single-species stands. While alternative management regimes have generally received less attention, this has been changing over the last three decades, especially in countries with developed economies. Reasons for this change include a combination of new information and concerns about the ecological consequences of intensive forestry practices and a willingness on the part of many forest owners and society to embrace a wider set of management objectives. Alternative silvicultural approaches are characterized by a set of fundamental principles, including avoidance of clearcutting, an emphasis on structural diversity and small-scale variability, deployment of mixed species with natural regeneration, and avoidance of intensive site-preparation methods. Methods： Our compilation of the authors＇ experiences and perspectives from various parts of the world aims to initiate a larger discussion concerning the constraints to and the potential of adopting alternative silvicultural practices. Results： The results suggest that a wider adoption of alternative silvicultural practices is currently hindered by a suite of ecological, economic, logistical, informational, cultural, and historical constraints. Individual contexts display their own unique combinations and relative significance of these constraints, and accordingly, targeted efforts, such as regulations and incentives, may help to overcome specific challenges. Conclusions： In a broader context, we propose that less emphases on strict applications of principles and on stand structures might provide additional flexibility and facilitate the adoption of alternative silvicultural regimes in a broader set of circumstanc

关键词： Natural Regeneration Forest Owner Stand Structure Commodity Production Private Landowner

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A Proposal for Mitigating Multiple Black-Hole Attack in Wireless Mesh Networks

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Wireless Sensor Network 2013年第4期5卷 76-83页

作者： Om Shree francis j. Ogwu Computer Science Department University of Botswana Gaborone Botswana

The Network Layer in wireless mesh networks is responsible for routing packets making it a prime target for intruders and hackers. Black-hole attack is a type of denial-of-service attack which when carried out can disrupt the services of this layer. This paper takes a look at some important detection and mitigation techniques and presents the drawbacks. After analysis of current mechanisms, the paper proposes RID-AODV, a security solution for multiple black-hole attack in wireless mesh networks. Based on the backbone of AODV, RID-AODV combines the ability of route skipping of IDSAODV and route failure correction using reverse route establishment of RAODV. The enhanced protocol RID-AODV, AODV, IDSAODV, and RAODV are implemented in a simulated environment using ns-2.35 simulator. The networks for each protocol are bombarded with up to ten black-hole nodes starting from zero. The results obtained are then analyzed and compared and a discussion is presented.

关键词： Mobile Ad-Hoc Network Wireless Mesh Networks Ad-Hoc On-Demand Distance Vector Black-Hole RADOV IDSAODV RID-AODV

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Karyotype Stability and Unbiased Fractionation in the Paleo-Allotetraploid Cucurbita Genomes

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Molecular Plant 2017年第10期10卷 1293-1306页

作者： Honghe Sun Shan WU Guoyu Zhang Chen jiao Shaogui Guo Yi Ren jie Zhang Haiying Zhang Guoyi Gong Zhangcai jia Fan Zhang jiaxing Tian William j. Lucas jeff j. doyle Haizhen Li Zhangjun Fei Yong Xu National Engineering Research Center for Vegetables Beijing Academy of Agriculture and Forestry Sciences Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China) Beijing Key Laboratory of Vegetable Germplasm Improvement Beijing 100097 China Boyce Thompson Institute Cornell University Ithaca NY 14853 USA Department of Plant Biology College of Biological Sciences University of California Davis CA 95616 USA Section of Plant Breeding & Genetics School of Integrated Plant Sciences Cornell University Ithaca NY 14853 USA USDA-ARS Robert W. Holley Center for Agriculture and Health Ithaca NY 14853 USA

The Cucurbita genus contains several economically important species in the Cucurbitaceae family. Here, we report high-quality genome sequences of C. maxima and C. moschata and provide evidence supporting an allotetraploidization event in Cucurbita. We are able to partition the genome into two homoeologous subgenomes based on different genetic distances to melon, cucumber, and watermelon in the Benincaseae tribe. We estimate that the two diploid progenitors successively diverged from Benincaseae around 31 and 26 million years ago （Mya）, respectively, and the allotetraploidization happened at some point between 26 Mya and 3 Mya, the estimated date when C. maxima and C. moschata diverged. The subgenomes have largely maintained the chromosome structures of their diploid progenitors. Such long-term karyotype stability after polyploidization has not been commonly observed in plant polyploids. The two subgenomes have retained similar numbers of genes, and neither subgenome is globally dominant in gene expression. Allele-specific expression analysis in the C. maxima ×C. moschata interspecific F1 hybrid and their two parents indicates the predominance of trans-regulatory effects underlying expression divergence of the parents, and detects transgressive gene expression changes in the hybrid correlated with heterosis in important agronomic traits. Our study provides insights into polyploid genome evolution and valuable resources for genetic improvement of cucurbit crops.

关键词： Cucurbita maxima Cucurbita moschata paleo-allotetraploid karyotype stability unbiased fractionation allele-specific expression

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Solving the Unbalanced Assignment Problem: Simpler Is Better

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American journal of Operations Research 2016年第4期6卷 296-299页

作者： Nathan Betts francis j. Vasko Department of Mathematics Kutztown University Kutztown PA USA

Recently, Yadaiah and Haragopal published in the American journal of Operations Research a new approach to solving the unbalanced assignment problem. They also provide a numerical example which they solve with their approach and get a cost of 1550 which they claim is optimum. This approach might be of interest;however, their approach does not guarantee the optimal solution. In this short paper, we will show that solving this same example from the Yadaiah and Haragopal paper by using a simple textbook formulation to balance the problem and then solve it with the classic Hungarian method of Kuhn yields the true optimal solution with a cost of 1520.

关键词： Assignment Problem Hungarian Method Textbook Formulation

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可得到高使用性能的一次压制／一次烧结生产工艺

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粉末冶金技术 2013年第1期31卷 62-68页

作者： francis j.Hanejko 韩凤麟 Hoeganaes Corporation

高密度粉末冶金零件(PM)意味着力学性能增高与零件的使用性能改进。虽然,高密度零件生产工艺不是新工艺(熔渗铜与二次压制/二次烧结工艺都已应用了许多年),但是最近10多年的发展,使着用一次压制/一次烧结工艺已可得到较高的密度。这些... 详细信息

高密度粉末冶金零件(PM)意味着力学性能增高与零件的使用性能改进。虽然,高密度零件生产工艺不是新工艺(熔渗铜与二次压制/二次烧结工艺都已应用了许多年),但是最近10多年的发展,使着用一次压制/一次烧结工艺已可得到较高的密度。这些先进的生产工艺叫做温压,其是一种利用有专利权的润滑剂与温模或温热粉末相结合的压制工艺。其在得到高密度烧结件的同时,仍然可保持粉末冶金固有的优势。可得到高密度的其它粉末冶金工艺还有模壁润滑与选择性表面致密化。对于每一种方法都进行了述评,并附带用资料证明了材料的性能与使用性能。

关键词：粉末冶金一次压制一次烧结温压高使用性能

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Exploiting a readily available but hard to digest resource:A review of exudativorous mammals identified thus far and how they cope in captivity

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Integrative Zoology 2018年第1期13卷 94-111页

作者： francis CABANA Ellen S.DIERENFELD Wirdateti Giuseppe DONATI K.A.I.NEKARIS Wildlife Nutrition Centre Wildlife Reserves Singapore Nocturnal Primate Research Group Oxford Brookes UniversityOxfordUK Ellen S.Dierenfeld LLCSt.LouisMissouri USA Zoological Division Indonesian Institute of ScienceCibinongIndonesia

Gum is a widely available carbohydrate,composed mainly of non-digestible structural *** mammalian enzymes can digest gum;therefore,a mammal ingesting gum must rely on microbial fermentation to access the energy it *** are relatively nutrient *** this,some mammals have evolved to exploit this food *** aim to review the literature for all mammal species which have been recorded to ingest gum,whether quantified or not,and discuss this in the context of their evolutionary *** also investigated the recommended captive diets for these species to look at whether gum is *** conducted a literature search on ISI Web of Knowledge to tabulate all mammal species observed ingesting gum and classified them as obligate,facultative or opportunistic *** encountered 94 mammal species that eat gum in the wild(27 obligate feeders,34 facultative feeders and 33 opportunistic feeders).Obligate feeders have entirely evolved to exploit this resource but were found to not be given gum in captivity,which may explain why they are failing to thrive,as opposed to facultative feeders,which have fewer *** may be necessary for the health of obligate feeders in *** research should focus on the physiological effects that gum ingestion poses on different digestive systems.

关键词： feeding ecology gum husbandry marsupial primate

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Novel 2-aryl-3,4,5-trihydroxypiperidines:Synthesis and glycosidase inhibition

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Chinese Chemical Letters 2013年第12期24卷 1059-1063页

作者： Hui Zhao Wu-Bao Wang Shinpei Nakagawa Yue-Mei jia Xiang-Guo Hu George W.j.Fleet francis X.Wilson Robert j.Nash Atsushi Kato Chu-Yi Yu Beijing National Laboratory for Molecular Science (BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of Sciences Department of Hospital Pharmacy University of Toyama2630 SugitaniToyama 930-0194Japan Chemistry Research Laboratory Department of ChemistryUniversity of Oxford Summit PLC 91Milton ParkAbingdonOxon OX14 4RYUK Phytoquest Limited IBERSPlas GogerddanCeredigionAberystwyth SY23 3EBWalesUK

Three pairs of novel 2-aryl-3,4,5-trihydroxypiperidines （6-8 and their enantiomers）, the piperidine analogues of the pyrrolidine alkaloids radicamine A and radicamine B, were prepared from six- membered cyclic nitrones through a concise two-step procedure, i.e., Grignard reagent addition and deprotection. These novel polyhydroxylated piperidine iminosugars were assayed against 10 types of enzymes. Only compound 8 exhibited weak inhibition （IC50 1080 μmol/L） against β-galactosidase from rat intestinal lactases.

关键词： 2-Aryl polyhydroxylated piperidine lminosugars Radicamine mimics Glycosidase inhibitors

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Tissue distribution and tumor uptake of folate receptor–targeted epothilone folate conjugate,BMS-753493,in CD2F1 mice after systemic administration

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Acta Pharmaceutica Sinica B 2016年第5期6卷 460-467页

作者： Hong Shen Lifei Wang Weiqi Chen Krista Menard Yang Hong Yuan Tian Samuel j.Bonacorsi W.Griffith Humphreys francis Y.Lee jinping Gan Pharmaceutical Candidate Optimization Bristol-Myers Squibb Research & Development Discovery Oncology Bristol-Myers Squibb Research & Development Chemistry Bristol-Myers Squibb Research & Development

To assess targeting of an epothilone folate conjugate(BMS-753493) to the folate receptor(FR)-overexpressed tumor in mice bearing both FRt and FR– tumors,a series of experiments were conducted by quantitative whole-body autoradiography(QWBA) and LC–MS/MS following *** of BMS-753493 or its active moiety,BMS-748285 in mice bearing FRt(98M109) and FR–(M109) *** showed [3H]BMS-753493–derived radioactivity was extensively distributed to various *** FR over-expressing 98M109 tumors showed consistently higher level of radioactivity than FR-negative tumors(i.e.,M109 tumors) up to 48 h post dose of [3H]BMS-753493,despite the magnitude of difference between the tumors is relatively small(generally 3 5-fold).The radioactivity level in 98M109 tumors was 2 12-fold of normal tissues except intestine/content at 48 h post *** selective radioactivity uptake into 98M109 tumors over M109 or normal tissues was observed after *** of the active epothilone,[3H]***–MS/MS measurements demonstrated that the concentrations of BMS-748285,presumably from hydrolysis of the folate conjugate,in 98M109 tumors were greater than those in M109 tumors after *** of BMS-753493(2–3-fold) whereas no differential uptake in the tumors following BMS-748285 *** data were consistent with radioactivity *** results demonstrated that the folate conjugation in BMS-753493 enabled moderately preferential distribution of the active epothilone to FR overexpressing 98M109 tumors,thereby supporting targeted delivery of cytotoxics through the folate receptor.

关键词： Folate receptor Tumor selective targeting Folate receptor–expressing tumor Epothilone folate conjugate Tissue distribution Tumor uptake

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Neurocognitive and mental health outcomes in children with tungiasis:a cross-sectional study in rural Kenya and Uganda

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Infectious Diseases of Poverty 2023年第6期12卷 98-98页

作者： Berrick Otieno Lynne Elson Abneel K.Matharu Naomi Riithi Esther Chongwo Khamis Katana Carophine Nasambu francis Mutebi Herman Feldmeier jürgen Krücken Ulrike Fillinger Amina Abubakar Kenya Medical Research Institute (KEMRI)-Wellcome Trust Programme Hospital Road Kilifi Kenya Centre for Tropical Medicine and Global Health Nuffield Department of Medicine University of Oxford Oxford UK International Centre of Insect Physiology and Ecology (ICIE) Human Health Theme Nairobi Kenya Institute for Parasitology and Tropical Veterinary Medicine Freie Universität Berlin Berlin Germany Institute for Human Development Aga Khan University Nairobi Kenya School of Veterinary Medicine and Animal Resources College of Veterinary Medicine Animal Resources and Biosecurity Makerere University Kampala Uganda Charité University Medicine Berlin Germany

Background Tungiasis,a neglected tropical parasitosis,disproportionately afects *** empirical studies have reported neurocognitive and mental health outcomes of children with ectoparasitic skin diseases like *** of tungiasis suggests it could detrimentally afect cognition and *** study pioneered the investigation of neurocognitive and mental health outcomes in children with *** This was a multi-site cross-sectional study including 454 quasi-randomly sampled school-children aged 8-14 from 48 randomly selected schools in two counties in Kenya and a district in *** participants were stratifed into infected and uninfected based on the presence of *** infected were further classifed into mild and severe infection groups based on the intensity of the ***,validated,and standardized measures of cognition and mental health such as Raven Matrices and Child Behaviour Checklist were used to collect *** tests including a multilevel,generalized mixed-efects linear models with family link set to identity were used to compare the scores of uninfected and infected children and to identify other potential risk factors for neurocognitive and behavioural *** When adjusted for covariates,mild infection was associated with lower scores in literacy[adjustedβ(aβ)=−8.9;95%confdence interval(CI)−17.2,−0.6],language(aβ=−1.7;95%CI−3.2,−0.3),cognitive fexibility(aβ=−6.1;95%CI−10.4,−1.7)and working memory(aβ=−0.3;95%CI−0.6,−0.1).Severe infection was associated with lower scores in literacy(aβ=−11.0;95%CI−19.3,−2.8),response inhibition,(aβ=−2.2;95%CI−4.2,−0.2),fne motor control(aβ=−0.7;95%CI−1.1,−0.4)and numeracy(aβ=−3;95%CI−5.5,−0.4).Conclusions This study provides frst evidence that tungiasis is associated with poor neurocognitive functioning in *** tungiasis is a chronic disease with frequent reinfections,such negative efects may potentially impair their development and l

关键词： Tungiasis Tunga penetrans Neglected tropical disease Neurocognition Mental health School-aged children Africa

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