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The spiral of applied research: A methodological view on integrated design research
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Selenate-enriched urea granules are a highly effective fertilizer for selenium biofortification of paddy rice grain
Citation: Premarathna, Lakmalie, Mike J. McLaughlin, Jason K. Kirby, Ganga M. Hettiarachchi, Samuel Stacey, and David J. Chittleborough. “Selenate-Enriched Urea Granules Are a Highly Effective Fertilizer for Selenium Biofortification of Paddy Rice Grain.” Journal of Agricultural and Food Chemistry 60, no. 23 (June 13, 2012): 6037–44. https://doi.org/10.1021/jf3005788.We examined the effects of applied selenium (Se) species, time of application, method of application and soil water management regime on accumulation of Se in rice plants. Plants were grown to maturity in a temperature- and humidity-controlled growth chamber using three water management methods: field capacity (FC), submerged until harvest, and submerged and drained two weeks before harvest; two Se species: selenate (SeO[subscript 4] ˉ²) and selenite (SeO[subscript 3]ˉ²) applied at a rate equivalent to 30 g haˉ¹; and four application methods: i) Se applied at soil preparation, ii) Se-enriched urea granules applied to floodwater at heading iii) foliar Se applied at heading and iv) fluid fertilizer Se applied to soil or floodwater at heading. Total Se concentrations in rice grains, husks, leaves, culms and roots were measured, as well as Se speciation in grains from the Se-enriched urea granule treatment. Highest Se
concentrations in the grain occurred with SeO[subscript 4] ˉ² and with fertilizer applied at heading stage; SeO[subscript 4]ˉ²-enriched urea granules applied at heading increased grain Se concentrations 5 to 6 fold (by 450-600 μg kgˉ¹) compared to the control (no fertilizer Se applied) in all water treatments. Under paddy conditions other Se fertilization strategies were much less effective. Drainage before harvesting caused Se to accumulate in/on rice roots, possibly through adsorption onto iron plaque on roots. Rice grains contained Se mainly in the organic form as selenomethionine (SeM) which comprised over 90 % of the total grain Se in treatments fertilized with SeO[subscript 4]ˉ² -enriched urea granules. The results of this study clearly show of the fertilizer strategies tested that biofortification of Se in rice grains can best be achieved in lowland rice by broadcast application of SeO[subscript 4]ˉ² -enriched urea granules to floodwater at heading stage
\u3cem\u3eRhizobium japonicum\u3c/em\u3e Mutants Defective in Symbiotic Nitrogen Fixation
Rhizobium japonicum strains 3I1b110 and 61A76 were mutagenized to obtain 25 independently derived mutants that produced soybean nodules defective in nitrogen fixation, as assayed by acetylene reduction. The proteins of both the bacterial and the plant portions of the nodules were analyzed by two-dimensional polyacrylamide gel electrophoresis. All of the mutants had lower-than-normal levels of the nitrogenase components, and all but four contained a prominent bacteroid protein not observed in wild-type bacteroids. Experiments with bacteria grown ex planta suggested that this protein was derepressed by the absence of ammonia. Nitrogenase component II of one mutant was altered in isoelectric point. The soluble plant fraction of the nodules of seven mutants had very low levels of heme, yet the nodules of five of these seven mutants contained the polypeptide of leghemoglobin. Thus, the synthesis of the globin may not be coupled to the content of available heme in soybean nodules. The nodules of the other two of these seven mutants lacked not only leghemoglobin but most of the other normal plant and bacteroid proteins. Ultrastructural examination of nodules formed by these two mutants indicated normal ramification of infection threads but suggested a problem in subsequent survival of the bacteria and their release from the infection threads
Eliciting public preferences for managing the public rights of way
Public Rights of Way (PROW) in England and Wales, provides a wide range of social and economic benefits to those other than owners of land. The protection and extension of PROW are an important way of encouraging people to engage in informal enjoyment of urban and rural areas, with beneficial consequences for health and welfare. In urban areas they provide networks of mobility and interaction for people at the community level, helping to reduce reliance on motorised transport. In the rural context they define access to the countryside, critically linked to recreation and tourism, as well as providing mobility networks for local residents. This study describes the use of a Choice Experiment (CE) to derive monetary estimates the social benefits of PROW in an English county.Choice Experiments, Public Rights of Way, Willingness to Pay, Land Economics/Use, Resource /Energy Economics and Policy,
Information Costs and Reverse Payment Settlements: Bridging the Gap Between the Courts and the Antitrust Agencies
Reverse payment settlements have attracted increased scrutiny due to the controversial presence of a payment from a brand-name drug company to a generic company that is ostensibly preparing to infringe on the branded company’s patent. The antitrust agencies and the courts settled into an intergovernmental stalemate regarding the appropriate framework of analysis to apply when reviewing antitrust challenges to these settlements. The FTC and DOJ have viewed the deals skeptically as a vehicle for competitors to split monopoly profits, but the lower courts have generally been deferential to what they identified as an exercise of a patent holder’s lawful right to exclude. Much has been written about which side is correct, yet there has been relatively little exploration of the source of the persistent disagreement.
Building off of Henry Smith’s property rights theory and the cognitive miser literature from Peter Lee, this Article explains that the long-standing disagreement stems from the judiciary’s application of information-cost-saving rules. Courts adopted a formalistic approach that would almost invariably uphold a reverse payment settlement because they tend to apply bright-line rules when dealing with property rights, and they are prone to adjudicate complex patent and patent-related cases in ways that economize on the costs of information processing. Although the Supreme Court resolved the disagreement by adopting a more information-demanding rule of reason approach in FTC v. Actavis, the cognitive miser phenomenon will continue to affect how courts adjudicate antitrust challenges to reverse-payment settlements
Exchange Bias Induced by the Fe3O4 Verwey transition
We present a study of the exchange bias in different configurations of V2O3
thin films with ferromagnetic layers. The exchange bias is accompanied by a
large vertical shift in the magnetization. These effects are only observed when
V2O3 is grown on top of Ni80Fe20 permalloy. The magnitude of the vertical shift
is as large as 60% of the total magnetization which has never been reported in
any system. X-Ray diffraction studies show that the growth conditions promote
the formation of a ferrimagnetic Fe3O4 interlayer. The change in the easy
magnetization axis of Fe3O4 across the Verwey transition at 120 K is correlated
with the appearance of exchange bias and vertical shift in magnetization. Both
phenomena disappear above 120 K, indicating for the first time a direct
relationship between the magnetic signature of the Verwey transition and
exchange bias.Comment: Accepted for publication Physical Review
Extensions of C*-dynamical systems to systems with complete transfer operators
Starting from an arbitrary endomorphism of a unital C*-algebra
we construct a bigger C*-algebra and extend onto in such a way
that the extended endomorphism has a unital kernel and a hereditary
range, i.e. there exists a unique non-degenerate transfer operator for
, called the complete transfer operator. The pair is
universal with respect to a suitable notion of a covariant representation and
depends on a choice of an ideal in . The construction enables a natural
definition of the crossed product for arbitrary .Comment: Compressed and submitted version, 9 page
Touch Versus Tech: When Technology Functions as a Barrier or a Benefit to Service Encounters
Interpersonal exchanges between customers and frontline service employees increasingly involve the use of technology, such as point-of-sale terminals, tablets, and kiosks. The present research draws on role and script theories to demonstrate that customer reactions to technology-infused service exchanges depend on the presence of employee rapport. When rapport is present during the exchange, the use of technology functions as an interpersonal barrier preventing the customer from responding in kind to employee rapport-building efforts, thereby decreasing service encounter evaluations. However, during service encounters in which employees are not engaging in rapport building, technology functions as an interpersonal barrier, enabling customers to retreat from the relatively unpleasant service interaction, thereby increasing service encounter evaluations. Two analyses using J.D. Power Guest Satisfaction Index data support the barrier and beneficial effects of technology use during service encounters with and without rapport, respectively. A follow-up experiment replicates this data pattern and identifies psychological discomfort as a key process that governs the effect. For managers, the results demonstrate the inherent incompatibility of initiatives designed to encourage employee–customer rapport with those that introduce technology into frontline service exchanges
Structural insights into the role of the Smoothened cysteine-rich domain in Hedgehog signalling.
Smoothened (Smo) is a member of the Frizzled (FzD) class of G-protein-coupled receptors (GPCRs), and functions as the key transducer in the Hedgehog (Hh) signalling pathway. Smo has an extracellular cysteine-rich domain (CRD), indispensable for its function and downstream Hh signalling. Despite its essential role, the functional contribution of the CRD to Smo signalling has not been clearly elucidated. However, given that the FzD CRD binds to the endogenous Wnt ligand, it has been proposed that the Smo CRD may bind its own endogenous ligand. Here we present the NMR solution structure of the Drosophila Smo CRD, and describe interactions between the glucocorticoid budesonide (Bud) and the Smo CRDs from both Drosophila and human. Our results highlight a function of the Smo CRD, demonstrating its role in binding to small-molecule modulators
Diffusion in a Time-dependent External Field
The problem of diffusion in a time-dependent (and generally inhomogeneous)
external field is considered on the basis of a generalized master equation with
two times, introduced in [1,2]. We consider the case of the quasi Fokker-Planck
approximation, when the probability transition function for diffusion
(PTD-function) does not possess a long tail in coordinate space and can be
expanded as a function of instantaneous displacements. The more complicated
case of long tails in the PTD will be discussed separately. We also discuss
diffusion on the basis of hydrodynamic and kinetic equations and show the
validity of the phenomenological approach. A new type of "collision" integral
is introduced for the description of diffusion in a system of particles, which
can transfer from a moving state to the rest state (with some waiting time
distribution). The solution of the appropriate kinetic equation in the external
field also confirms the phenomenological approach of the generalized master
equation.Comment: 18 pages, no figure
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