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Cryopreservation of winter-dormant apple: III Bud water status and survival after cooling to -30°c and during recovery from cryopreservation
Abstract
In a continuing study to improve the efficiency of dormant bud cryopreservation for
tissues hardened in maritime climates, the water status of dormant buds was monitored
between -4°C and recovery from liquid nitrogen (LN). Measurement of water content, simple
thermal analysis and differential scanning calorimetry were employed. Buds did not lose
water during cooling to, or holding at -30°C indicating that cryodehydration and/or other
adaptive responses contributed during this essential step. A bud exotherm that was an artefact
of warming was detected due to necessary handling at -4°C before cooling to -30°C. There
were no significant differences between cultivars with respect to water status at -30°C or
immediately upon rewarming from LN despite significant differences in post-LN survival.
Buds rehydrated in 5 days, but up to 14 days may be needed for recovery for some cultivars.
In some instances buds could be grafted without rehydration, taking up water across the early
graft union
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Cryopreservation of winter-dormant apple buds: II - tissue water status after desiccation at -4°c and before further cooling
Abstract
The established protocol for the cryopreservation of winter-dormant Malus buds requires
that stem explants, containing a single, dormant bud are desiccated at -4°C, for up to 14 days,
to reduce their water content to 25-30% of fresh weight. Using three apple cultivars, with
known differences in response to cryopreservation, the pattern of evaporative water loss has
been characterised, including early freezing events in the bud and cortical tissues that allow
further desiccation by water migration to extracellular ice. There were no significant
differences between cultivars in this respect or in the proportions of tissue water lost during
the desiccation process. Differential Scanning Calorimetry (to -90°C) of intact buds indicated
that bud tissues of the cultivar with the poorest response to cryopreservation had the highest
residual water content at the end of the desiccation process and froze at the highest
temperature
Keywords: Malus, cryopreservation, dormant bud, dehydratio
Search for direct production of charginos, neutralinos and sleptons in final states with two leptons and missing transverse momentum in pp collisions at âs = 8TeV with the ATLAS detector
Searches for the electroweak production of charginos, neutralinos and sleptons in final states characterized by the presence of two leptons (electrons and muons) and missing transverse momentum are performed using 20.3 fbâ1 of proton-proton collision data at sâ = 8 TeV recorded with the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. Limits are set on the masses of the lightest chargino, next-to-lightest neutralino and sleptons for different lightest-neutralino mass hypotheses in simplified models. Results are also interpreted in various scenarios of the phenomenological Minimal Supersymmetric Standard Model
Measurement of the production of a W boson in association with a charm quark in pp collisions at âs = 7 TeV with the ATLAS detector
The production of a W boson in association with a single charm quark is studied using 4.6 fbâ1 of pp collision data at sâ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26â0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio Ď(W + +cÂŻÂŻ)/Ď(W â + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the sâsÂŻÂŻÂŻ quark asymmetry
emiT: an apparatus to test time reversal invariance in polarized neutron decay
We describe an apparatus used to measure the triple-correlation term (\D
\hat{\sigma}_n\cdot p_e\times p_\nu) in the beta-decay of polarized neutrons.
The \D-coefficient is sensitive to possible violations of time reversal
invariance. The detector has an octagonal symmetry that optimizes
electron-proton coincidence rates and reduces systematic effects. A beam of
longitudinally polarized cold neutrons passes through the detector chamber,
where a small fraction beta-decay. The final-state protons are accelerated and
focused onto arrays of cooled semiconductor diodes, while the coincident
electrons are detected using panels of plastic scintillator. Details regarding
the design and performance of the proton detectors, beta detectors and the
electronics used in the data collection system are presented. The neutron beam
characteristics, the spin-transport magnetic fields, and polarization
measurements are also described.Comment: 15 pages, 13 figure
The most creative organization in the world? The BBC, 'creativity' and managerial style
The managerial styles of two BBC directors-general, John Birt and Greg Dyke, have often been contrasted but not so far analysed from the perspective of their different views of 'creative management'. This article first addresses the orthodox reading of 'Birtism'; second, it locates Dyke's 'creative' turn in the wider context of fashionable neo-management theory and UK government creative industries policy; third, it details Dyke's drive to change the BBC's culture; and finally, it concludes with some reflections on the uncertainties inherent in managing a creative organisation
The UK market for energy service contracts in 2014â2015
This paper provides an overview of the UK market for energy service contracts in 2014 and highlights the growing role of intermediaries. Using information from secondary literature and interviews, it identifies the businesses offering energy service contracts, the sectors and organisations that are purchasing those contracts, the types of contract that are available, the areas of market growth and the reasons for that growth. The paper finds that the UK market is relatively large, highly diverse, concentrated in particular sectors and types of site and overwhelmingly focused upon established technologies with high rates of return. A major driver is the emergence of procurement frameworks for energy service contracts in the public sector. These act as intermediaries between clients and contractors, thereby lowering transaction costs and facilitating learning. The market is struggling to become established in commercial offices, largely as a result of split incentives, and is unlikely to develop further in this sector without different business models, tenancy arrangements and policy initiatives. Overall, the paper concludes that energy service contracts can play an important role in the transition to a low-carbon economy, especially when supported by intermediaries, but their potential is still limited by high transaction costs
Affordances, constraints and information flows as âleverage pointsâ in design for sustainable behaviour
Copyright @ 2012 Social Science Electronic PublishingTwo of Donella Meadows' 'leverage points' for intervening in systems (1999) seem particularly pertinent to design for sustainable behaviour, in the sense that designers may have the scope to implement them in (re-)designing everyday products and services. The 'rules of the system' -- interpreted here to refer to affordances and constraints -- and the structure of information flows both offer a range of opportunities for design interventions to in fluence behaviour change, and in this paper, some of the implications and possibilities are discussed with reference to parallel concepts from within design, HCI and relevant areas of psychology
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