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A common phytoene synthase mutation underlies white petal varieties of the California poppy.
The California poppy (Eschscholzia californica) is renowned for its brilliant golden-orange flowers, though white petal variants have been described. By whole-transcriptome sequencing, we have discovered in multiple white petal varieties a single deletion leading to altered splicing and C-terminal truncation of phytoene synthase (PSY), a key enzyme in carotenoid biosynthesis. Our findings underscore the diverse roles of phytoene synthase in shaping horticultural traits, and resolve a longstanding mystery of the regaled golden poppy
Origin and evolution of the Saturn system: Observational consequences
A number of important cosmogonic questions concerning the Saturn system can be addressed with a Saturn-orbiter-dual-probe spacecraft mission. These questions include: The origin of the Saturn system; the source of Saturn's excess luminosity; the mechanism by which the irregular satellites were captured; the influence of Saturn's early luminosity on the composition of its regular satellites; and the origin of the rings. The first two topics can be studied by measurements made from an entry probe into Saturn's atmosphere, while the remaining issues can be investigated by measurements conducted from an orbiter. Background information is provided on these five questions describing the critical experiments needed to help resolve them
Temperature structure of nongrey planetary atmospheres
Temperature structure of nongrey planetary atmosphere
Models of temperature structure and general circulation
Titan has a warm upper atmosphere. Whether it has a warm lower atmosphere and hot surface is an open question. This question is important not only from a purely scientific point of view, but also for assessing the viability of a Titan entry probe
A critical test of the electrical discharge model of the Venus microwave emission
Critical test of electric discharge model for Venus microwave emissio
Physical properties of aerosols in Titan's atmosphere as deduced from visible observations
Analysis of the absolute value of Titan's albedo and its variation with increasing phase angle has yielded constraints on the optical properties and average particle size of the aerosols responsible for the scattering of visible light. The real index of refraction of the scattering material lies within the range 1.5 approximately less than nr approximately less than 2.0 and the average particle size is somewhere between 0.2 micrometer and 0.4 micrometer. The amount of limb darkening produced by these models leads to an occultation radius of approximately 2700 km
Topological censorship from the initial data point of view
We introduce a natural generalization of marginally outer trapped surfaces,
called immersed marginally outer trapped surfaces, and prove that three
dimensional asymptotically flat initial data sets either contain such surfaces
or are diffeomorphic to R^3. We establish a generalization of the Penrose
singularity theorem which shows that the presence of an immersed marginally
outer trapped surface generically implies the null geodesic incompleteness of
any spacetime that satisfies the null energy condition and which admits a
non-compact Cauchy surface. Taken together, these results can be viewed as an
initial data version of the Gannon-Lee singularity theorem. The first result is
a non-time-symmetric version of a theorem of Meeks-Simon-Yau which implies that
every asymptotically flat Riemannian 3-manifold that is not diffeomorphic to
R^3 contains an embedded stable minimal surface. We also obtain an initial data
version of the spacetime principle of topological censorship. Under physically
natural assumptions, a 3-dimensional asymptotically flat initial data set with
marginally outer trapped boundary and no immersed marginally outer trapped
surfaces in its interior is diffeomorphic to R^3 minus a finite number of open
balls. An extension to higher dimensions is also discussed.Comment: v2: Appendix added, Theorem 5.1 improved, other minor changes. To
appear in J. Diff. Geo
Using Kotter’s Eight Stage Process to Manage an Organisational Change Program: Presentation and Practice
© 2014, Springer Science+Business Media New York. Kotter’s eight stage process for creating a major change is one of the most widely recognised models for change management, and yet there are few case studies in the academic literature that enquire into how this process has been used in practice. This paper describes a change manager’s action research enquiring into the use of this Process to manage a major organisational change. The change was initiated in response to the organisation’s ageing workforce, introducing a knowledge management program focusing on the interpersonal aspects of knowledge retention. Although Kotter’s process emphasises a top-led model for change, the change team found it was necessary to engage at many levels of the organisation to implement the organisational change. The process is typically depicted as a linear sequence of steps. However, this image of the change process was found to not represent the complexity of the required action. Managing the change required the change team to facilitate multiple concurrent instances of Kotter’s process throughout the organisation, to re-create change that was locally relevant to participants in the change process
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