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Hydrologic Data for Urban Studies in The Austin Metropolitan Area, Texas, 1986
The report references Waller Creek and includes data from surrounding watersheds.Waller Creek Working Grou
Energy-harvesting materials
It is shown how key features of natural photosynthesis can be emulated in novel materials based on photoactive multichromophore arrays and crystals. A major consideration in the design of such systems is the means of channeling electronic excitation from sites of light absorption to centers where it is stored or released. Storage is often achieved by driving charge separation or, for the longer term, a more complex chemical reaction whilst rapid release is commonly associated with frequency up-converted emission. In each case channeling to the conversion site generally entails a multi-step energy transfer mechanism whose efficiency is determined by the arrangement and electronic properties of the array chromophores or ions, guided in the more complex systems by a spectroscopic gradient that promotes overall directionality. The functional cascade molecules known as photoactive dendrimers are exemplars of this approach. The latest developments involve new mechanisms for concerted excitation transfer in multichromophore systems, leading towards the tailoring and exploitation of optical nonlinearities for high intensity energy pooling applications
Electromagnetic Radiation
Electromagnetic radiation, commonly referred to as light, underpins all spectroscopic techniques, ranging from the highly energetic gamma rays, through x-rays, ultraviolet, visible, infrared, microwaves to the low-energy radio waves. The principles of wave- and particle-like behaviour determine the nature of the radiation and its interaction with matter, whether in the form of subatomic, atomic, molecular or macromolecular structures
Gravitational energy as dark energy: Towards concordance cosmology without Lambda
I briefly outline a new physical interpretation to the average cosmological
parameters for an inhomogeneous universe with backreaction. The variance in
local geometry and gravitational energy between ideal isotropic observers in
bound structures and isotropic observers at the volume average location in
voids plays a crucial role. Fits of a model universe to observational data
suggest the possibility of a new concordance cosmology, in which dark energy is
revealed as a mis-identification of gravitational energy gradients that become
important when voids grow at late epochs.Comment: 8 pages, 1 figure; in E. Pecontal, T. Buchert, Ph. Di Stefano and Y.
Copin (eds), "Dark Energy and Dark Matter: Observations, Experiments and
Theories", Proceedings, Lyon, 7-11 July, 200
The analysis of fluorophore orientation by multiphoton fluorescence microscopy
The accessibility of tunable, ultrafast laser sources has spurred the development and wide application of specialized microscopy techniques based on chromophore fluorescence following two- and three-photon absorption. The attendant advantages of such methods, which have led to a host of important applications including three-dimensional biological imaging, include some features that have as yet received relatively little attention. In the investigation of cellular or subcellular processes, it is possible to discern not only on the location, concentration, and lifetime of molecular species, but also the orientations of key fluorophores. Detailed information can be secured on the degree of orientational order in specific cellular domains, or the lifetimes associated with the rotational motions of individual fluorophores; both are accessible from polarization-resolved measurements. This paper reports the equations that are required for any such investigation, determined by robust quantum electrodynamical derivation. The general analysis, addressing a system of chromophores oriented in three dimensions, determines the fluorescence signal produced by the nonlinear polarizations that are induced by multiphoton absorption, allowing for any rotational relaxation. The results indicate that multiphoton imaging can be further developed as a diagnostic tool, either to selectively discriminate micro-domains in vivo, or to monitor dynamical changes in intracellular fluorophore orientation
Farm growth and exit: consequences of EU dairy policy reform for Dutch dairy farming
The purpose of this paper is to analyse farm growth and exit and its interaction in Dutch dairy farming as consequences of the 2003 CAP reform and 2008 CAP Health Check. Results indicate that the decision to exit dairy farming is largely determined by household characteristics as age and the size of the household. Farm growth is strongly influenced by the availability of labour, capital and land. Simulation results show that the dairy policy reforms reduce farm growth and exit. This is mainly caused by the quota increases
'Really on the ball': exploring the implications of teachers' PE-CPD experience
Continuing professional development (CPD) is currently high on the Scottish Education agenda. Recent curriculum reform in Scotland, with the introduction of Curriculum for Excellence, places physical education (PE) at the forefront for its role in directly supporting learners' mental, emotional, social and physical well-being. This emphasis on PE, along with concerns about the health of the nation, has resulted in a nationwide initiative providing non-specialist teachers of primary PE with the opportunity to develop a specialism in the subject through government-funded CPD programmes at postgraduate level. Using Knowles' andragogical model as a framework, this paper reports data from a larger research study that evaluated a Scottish PE-CPD initiative. This paper comprises a single case holistic study investigating the impact and implications of a PE-CPD programme through the professional learning journeys, from the outset until completion, of four teachers: a nursery teacher, a class teacher, a cluster cover teacher and a PE specialist who participated in the programme. Data were collected over one academic year using two-stage questionnaire interviews and were analysed thematically with special attention given to the emerging general themes to achieve a holistic understanding of the case. Study findings endorse the positive impact of using the andragogical model of adult learning combined with the literature-supported characteristics of effective PE-CPD programmes. Teachers' perspectives on their CPD experiences, integration of acquired learning into working contexts and teaching post-PE-CPD were then examined to determine the next steps. This led to critical reflection on the implications of the findings for the teachers' ongoing professional development. We then challenged the role that university providers play in supporting teachers' lifelong learning. Instead, we suggest new school-university partnerships and alternative ways to support capacity building and lifelong learning towards a sustainable transformational change in Scotland's primary PE
Prediction for Nonabelian Fine Structure Constants from Multicriticality
In developing a model for predicting the nonabelian gauge coupling constants
we argue for the phenomenological validity of a ``principle of multiple point
criticality''. This is supplemented with the assumption of an ``(grand)
anti-unified'' gauge group that, at the Planck scale, breaks down
to the diagonal subgroup. Here is the number of generations which is
assumed to be 3. According to this ``multiple point criticality principle'',
the Planck scale experimental couplings correspond to multiple point couplings
of the bulk phase transition of a lattice gauge theory (with gauge group
). Predictions from this principle agree with running
nonabelian couplings (after an extrapolation to the Planck scale using the
assumption of a ``desert'') to an accuracy of 7\%. As an explanation for the
existence of the multiple point, a speculative model using a glassy lattice
gauge theory is presented.Comment: 42, NBI-HE-93-2
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