15 research outputs found

    Agrobacterium-mediated transformation of safflower and the efficient recovery of transgenic plants via grafting

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    <p>Abstract</p> <p>Background</p> <p>Safflower <it>(Carthamus tinctorius L.) </it>is a difficult crop to genetically transform being susceptible to hyperhydration and poor <it>in vitro </it>root formation. In addition to traditional uses safflower has recently emerged as a broadacre platform for the production of transgenic products including modified oils and pharmaceutically active proteins. Despite commercial activities based on the genetic modification of safflower, there is no method available in the public domain describing the transformation of safflower that generates transformed T<sub>1 </sub>progeny.</p> <p>Results</p> <p>An efficient and reproducible protocol has been developed with a transformation efficiency of 4.8% and 3.1% for S-317 (high oleic acid content) and WT (high linoleic acid content) genotypes respectively. An improved safflower transformation T-DNA vector was developed, including a secreted <it>GFP </it>to allow non-destructive assessment of transgenic shoots. Hyperhydration and necrosis of <it>Agrobacterium</it>-infected cotyledons was effectively controlled by using iota-carrageenan, L-cysteine and ascorbic acid. To overcome poor <it>in vitro </it>root formation for the first time a grafting method was developed for safflower in which ~50% of transgenic shoots develop into mature plants bearing viable transgenic T<sub>1 </sub>seed. The integration and expression of secreted <it>GFP </it>and hygromycin genes were confirmed by PCR, Southern and Western blot analysis. Southern blot analysis in nine independent lines indicated that 1-7 transgenes were inserted per line and T<sub>1 </sub>progeny displayed Mendelian inheritance.</p> <p>Conclusions</p> <p>This protocol demonstrates significant improvements in both the efficiency and ease of use over existing safflower transformation protocols. This is the first complete method of genetic transformation of safflower that generates stably-transformed plants and progeny, allowing this crop to benefit from modern molecular applications.</p

    Accommodating 'others'?: housing dispersed, forced migrants in the UK

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    Utilising insights from a qualitative study in the city of Leeds (UK), this paper considers issues related to the housing of dispersed forced migrants. The term 'dispersed forced migrants' is used here as a general label to include four groups of international migrants (i.e. refugees, asylum seekers, those with humanitarian protection status and failed asylum seekers) who have previously been dispersed, on a no choice basis, to a variety of locations across the UK under the requirements of the Immigration and Asylum Act (1999). The tiering of housing entitlement that exists within the generic population of dispersed forced migrants (a consequence of the particular socio-legal status assigned to individuals), and its role in rendering migrants susceptible to homelessness is outlined. The adequacy/standard of accommodation made available to forced migrants is also discussed. It is concluded that current arrangements fail to meet the basic housing needs of many forced migrants. Any future improvement in this situation will require a significant shift in government policy

    Computational optical imaging with a photonic lantern

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    [EN] The thin and flexible nature of optical fibres often makes them the ideal technology to view biological processes in-vivo, but current microendoscopic approaches are limited in spatial resolution. Here, we demonstrate a route to high resolution microendoscopy using a multicore fibre (MCF) with an adiabatic multimode-to-single-mode "photonic lantern" transition formed at the distal end by tapering. We show that distinct multimode patterns of light can be projected from the output of the lantern by individually exciting the single-mode MCF cores, and that these patterns are highly stable to fibre movement. This capability is then exploited to demonstrate a form of single-pixel imaging, where a single pixel detector is used to detect the fraction of light transmitted through the object for each multimode pattern. A custom computational imaging algorithm we call SARA-COIL is used to reconstruct the object using only the pre-measured multimode patterns themselves and the detector signals.This work was funded through the "Proteus" Engineering and Physical Sciences Research Council (EPSRC) Interdisciplinary Research Collaboration (IRC) (EP/K03197X/1), by the Science and Technology Facilities Council (STFC) through STFC-CLASP grants ST/K006509/1 and ST/K006460/1, STFC Consortium grants ST/N000625/1 and ST/N000544/1. S.L. acknowledges support from the National Natural Science Foundation of China under Grant no. 61705073. DBP acknowledges support from the Royal Academy of Engineering, and the European Research Council (PhotUntangle, 804626). The authors thank Philip Emanuel for the use of his confocal image of A549 cells and Eckhardt Optics for their image of the USAF 1951 target. 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    Evidence-based Kernels: Fundamental Units of Behavioral Influence

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    This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior–influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of its components would render it inert. Existing evidence shows that a variety of kernels can influence behavior in context, and some evidence suggests that frequent use or sufficient use of some kernels may produce longer lasting behavioral shifts. The analysis of kernels could contribute to an empirically based theory of behavioral influence, augment existing prevention or treatment efforts, facilitate the dissemination of effective prevention and treatment practices, clarify the active ingredients in existing interventions, and contribute to efficiently developing interventions that are more effective. Kernels involve one or more of the following mechanisms of behavior influence: reinforcement, altering antecedents, changing verbal relational responding, or changing physiological states directly. The paper describes 52 of these kernels, and details practical, theoretical, and research implications, including calling for a national database of kernels that influence human behavior

    Wireless Sensor Networks: A Survey on the State of the Art and the 802.15.4 and Zigbee Standards

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    NoWireless sensor networks are an emerging technology for low-cost, unattended monitoring of a wide range of environments. Their importance has been enforced by the recent delivery of the IEEE 802.15.4 standard for the physical and MAC layers and the forthcoming ZigBee standard for the network and application layers. The fast progress of research on energy efficiency, networking, data management and security in wireless sensor networks, and the need to compare with the solutions adopted in the standards motivates the need for a survey on this field
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