Band structure and reflectance for a nonlinear one-dimensional photonic crystal

We consider a model for a one-dimensional photonic crystal formed by a succession of Kerr-type equidistant spaceless interfaces immersed in a linear medium. We calculate the band structure and reflectance of this structure as a function of the incident wave intensity, and find two main behaviors: the appearance of prohibited bands, and the separation and narrowing of these bands. A system with these features is obtained by alternating very thin slabs of a soft matter material with thicker solid films, which can be used to design a device to control light propagation for specific wavelength intervals and light intensities.Comment: 6 pages, 6 figure

Classical dynamics of a two-species Bose-Einstein condensate in the presence of nonlinear maser processes

The stability analysis of a generalized Dicke model, in the semi-classical limit, describing the interaction of a two-species Bose-Einstein condensate driven by a quantized field in the presence of Kerr and spontaneous parametric processes is presented. The transitions from Rabi to Josephson dynamics are identified depending on the relative value of the involved parameters. Symmetry-breaking dynamics are shown for both types of coherent oscillations due to the quantized field and nonlinear optical processes.Comment: 12 pages, 5 figures. Accepted for publication as chapter in "Spontaneous Symmetry Breaking, Self-Trapping, and Josephson Oscillations in Nonlinear Systems

Greenhushing: the deliberate under communicating of sustainability practices by tourism businesses

Greenhushing selectively communicates fewer pro-sustainability actions by businesses than are practiced; based on a perception of customers’ rights to consumerism. We first studied the gap between the communication of sustainability practices in the audits and websites of 31 small rural tourism businesses in the Peak District National Park (UK). The analysis showed that businesses only communicate 30% of all the sustainability actions practiced. Their websites emphasised customer benefits, using explicit, affective, experiential and active language that legitimises the customers’ hedonistic use of the landscape, while downplaying complex issues and normalising sustainability to reduce customer guilt. Just one website mentioned climate change. We found that greenhushing results from a low moral intensity, masking potentially negative consequences of perceived lower competence, whilst protecting business from more cynical consumers who may interpret their statements as hypocritical. Subsequent textual analysis and interviews were used to understand how communication constitutes these organisations. We propose that greenhushing reshapes and constitutes tourism businesses through their communications. Moreover, greenhushing is a form of public moralisation that adopts communication practices similar to greenwashing, reflecting the social norms expected from a business; however, in this case, located in a moral muteness, rather than moral hypocrisy, that businesses accept but resent

Guidelines for Innovation Platforms in Agricultural Research for Development : Decision support for research, development and funding agencies on how to design, budget and implement impactful Innovation Platforms

Innovation Platforms are fast becoming part of the mantra of agricultural research for development projects and programmes. Their basic tenet is that stakeholders depend on one another to achieve agricultural development outcomes, and hence need a space where they can learn, negotiate, and coordinate to overcome challenges and capture opportunities through a facilitated innovation process. This important publication provides a critical analysis of Innovation Platforms, their defining features, key functions, and what they can and – as importantly – cannot do.It will be invaluable reading both for those who fund development projects andprogrammes and would like to understand when Innovation Platforms are the approach of choice, and for those practitioners who implement and facilitate Innovation Platforms and would like to understand better their design principles and practical implementation issues.Because Innovation Platforms have been successful in addressing agricultural challenges, there is a risk that they will be promoted as a panacea for all problems in the agricultural sector. As the authors make clear, however, not all constraints will require Innovation Platforms and, if there is a simpler and cheaper alternative, that should be the first choice. It is essential to think more critically about when, how, and in what form Innovation Platforms can contribute meaningfully to Agricultural development impacts.The document was developed through a learning collaboration between CGIARresearch centres and other academic and more applied research centres. Elevenof the 15 CGIAR centres participated and contributed their expertise and experiences across multiple agricultural systems, geographies, and types of complex constraint. The booklet provides information grounded in a rich practical experience of key design and implementation principles, and the financial and human resources that need to be made available, and it makes suggestions for more effective monitoring, evaluation, and learning. It also lists reference materials, answers frequently asked questions, and provides a decision support tool for research, development, and funding agencies.All in all, this publication offers a lot for those who aspire to make sensible use ofInnovation Platforms in pursuing agricultural development

Independent phenotypic plasticity axes define distinct obesity sub-types.

Studies in genetically ‘identical’ individuals indicate that as much as 50% of complex trait variation cannot be traced to genetics or to the environment. The mechanisms that generate this ‘unexplained’ phenotypic variation (UPV) remain largely unknown. Here, we identify neuronatin (NNAT) as a conserved factor that buffers against UPV. We find that Nnat deficiency in isogenic mice triggers the emergence of a bi-stable polyphenism, where littermates emerge into adulthood either ‘normal’ or ‘overgrown’. Mechanistically, this is mediated by an insulin-dependent overgrowth that arises from histone deacetylase (HDAC)-dependent β-cell hyperproliferation. A multi-dimensional analysis of monozygotic twin discordance reveals the existence of two patterns of human UPV, one of which (Type B) phenocopies the NNAT-buffered polyphenism identified in mice. Specifically, Type-B monozygotic co-twins exhibit coordinated increases in fat and lean mass across the body; decreased NNAT expression; increased HDAC-responsive gene signatures; and clinical outcomes linked to insulinemia. Critically, the Type-B UPV signature stratifies both childhood and adult cohorts into four metabolic states, including two phenotypically and molecularly distinct types of obesity