Space, conversations and place: lessons and questions from organisational development

Physical workspace is distinguished from workplace. The latter embodies culture and should become the greater concern of FM. In the field of individual and group development spaces can add an extra gear to stimulate cognitive processes. We provide various examples and suggest modern workplaces, with their emphasis on interaction need to also focus on environments and spaces for individual and collective reflection

The nature of science as a foundation for fostering a better understanding of evolution

Misunderstandings of the nature of science (NOS) contribute greatly to resistance to evolutionary theory especially among non-scientific audiences. Here we delineate three extended instructional examples that make extensive use of NOS to establish a foundation upon which to more successfully introduce evolution. Specifically, these instructional examples enable students to consider evolutionary biology using NOS as a lens for interpretation of evolutionary concepts. We have further found, through our respective research efforts and instructional experiences, that a deep understanding of NOS helps students understand and accept the scientific validity of evolution and, conversely, that evolution provides an especially effective context for helping students and teachers to develop a deep understanding of the nature of science. Based on our research and instructional experiences, we introduce six key factors necessary for enhanced instructional success in teaching evolution. These factors are: (1) foster a deep understanding of NOS; (2) use NOS as a lens for evolution instruction; (3) explicitly compare evolution to alternative explanations; (4) focus on human evolution (where possible); (5) explicitly recognize the power of historical inference and (6) use active, social learning. Finally, we elaborate and ground these key factors in supporting literature

Thermodynamics of the one-dimensional SU(4) symmetric spin-orbital model

The ground state properties and the thermodynamics of the one-dimensional SU(4) symmetric spin system with orbital degeneracy are investigated using the quantum Monte Carlo loop algorithm. The spin-spin correlation functions exhibit a 4-site periodicity, and their low temperature behavior is controlled by two correlation lengths that diverge like the inverse temperature, while the entropy is linear in temperature and its slope is consistent with three gapless modes of velocity $\pi/2$. The physical implications of these results are discussed.Comment: 4 pages, 4 figures, RevTe

Ultrafast supercontinuum spectroscopy of carrier multiplication and biexcitonic effects in excited states of PbS quantum dots

We examine the multiple exciton population dynamics in PbS quantum dots by ultrafast spectrally-resolved supercontinuum transient absorption (SC-TA). We simultaneously probe the first three excitonic transitions over a broad spectral range. Transient spectra show the presence of first order bleach of absorption for the 1S_h-1S_e transition and second order bleach along with photoinduced absorption band for 1P_h-1P_e transition. We also report evidence of the one-photon forbidden 1S_{h,e}-1P_{h,e} transition. We examine signatures of carrier multiplication (multiexcitons for the single absorbed photon) from analysis of the first and second order bleaches, in the limit of low absorbed photon numbers (~ 10^-2), at pump energies from two to four times the semiconductor band gap. The multiexciton generation efficiency is discussed both in terms of a broadband global fit and the ratio between early- to long-time transient absorption signals.. Analysis of population dynamics shows that the bleach peak due to the biexciton population is red-shifted respect the single exciton one, indicating a positive binding energy.Comment: 16 pages, 5 figure

Body Temperature In Captive Long-Beaked Echidnas (Zaglossus Bartoni)

The routine occurrence of both short-term (daily) and long-term torpor (hibernation) in short-beaked echidnas, but not platypus, raises questions about the third monotreme genus, New Guinea's Zaglossus. We measured body temperatures (Tb) with implanted data loggers over three and a half years in two captive Zaglossus bartoni at Taronga Zoo, Sydney. The modal Tb of both long-beaks was 31 degrees C, similar to non-hibernating short-beaked echidnas, Tachyglossus aculeatus, in the wild (30-32 degrees C) and to platypus (32 degrees C), suggesting that this is characteristic of normothermic monotremes. Tb cycled daily, usually over 2-4 degrees C. There were some departures from this pattern to suggest periods of inactivity but nothing to indicate the occurrence of long-term torpor. In contrast, two short-beaked echidnas monitored concurrently in the same pen showed extended periods of low Tb in the cooler months (hibernation) and short periods of torpor at any time of the year, as they do in the wild. Whether torpor or hibernation occurs in Zaglossus in the wild or in juveniles remains unknown. However, given that the environment in this study was conducive to hibernation in short-beaks, which do not easily enter torpor in captivity, and their large size, we think that torpor in wild adult Zaglossus is unlikely

Elementary excitations of the symmetric spin-orbital model: The XY limit

The elementary excitations of the 1D, symmetric, spin-orbital model are investigated by studying two anisotropic versions of the model, the pure XY and the dimerized XXZ case, with analytical and numerical methods. While they preserve the symmetry between spin and orbital degrees of freedom, these models allow for a simple and transparent picture of the low--lying excitations: In the pure XY case, a phase separation takes place between two phases with free--fermion like, gapless excitations, while in the dimerized case, the low-energy effective Hamiltonian reduces to the 1D Ising model with gapped excitations. In both cases, all the elementary excitations involve simultaneous flips of the spin and orbital degrees of freedom, a clear indication of the breakdown of the traditional mean-field theory.Comment: Revtex, two figure

The Physical Origins of Entropy Production, Free Energy Dissipation and their Mathematical Representations

A complete mathematical theory of nonequilibrium thermodynamics of stochastic systems in terms of master equations is presented. As generalizations of isothermal entropy and free energy, two functions of states play central roles: the Gibbs entropy $S$ and the relative entropy $F$, which are related via the stationary distribution of the stochastic dynamics. $S$ satisfies the fundamental entropy balance equation $dS/dt=e_p-h_d/T$ with entropy production rate $e_p\ge 0$ and heat dissipation rate $h_d$, while $dF/dt=-f_d\le 0$. For closed systems that satisfy detailed balance: $Te_p(t)=f_d(t)$. For open system one has $Te_p(t)=f_d(t)+Q_{hk}(t)$ where the housekeeping heat $Q_{hk}\ge 0$ was first introduced in the phenomenological nonequilibrium steady state thermodynamics. Entropy production $e_p$ consists of free energy dissipation associated with spontaneous relaxation, $f_d$, and active energy pumping that sustains the open system $Q_{hk}$. The amount of excess heat involved in the relaxation $Q_{ex}=h_d-Q_{hk} = f_d-T(dS/dt)$.Comment: 4 pages, no figure

Duality, thermodynamics, and the linear programming problem in constraint-based models of metabolism

It is shown that the dual to the linear programming problem that arises in constraint-based models of metabolism can be given a thermodynamic interpretation in which the shadow prices are chemical potential analogues, and the objective is to minimise free energy consumption given a free energy drain corresponding to growth. The interpretation is distinct from conventional non-equilibrium thermodynamics, although it does satisfy a minimum entropy production principle. It can be used to motivate extensions of constraint-based modelling, for example to microbial ecosystems.Comment: 4 pages, 2 figures, 1 table, RevTeX 4, final accepted versio

Pamela: development of the RF system for a non-relativistic non-scaling FFAG

The PAMELA project(Particle Accelerator For MEdical Applications) currently consists of the design of a particle therapy facility. The project, which is in the design phase, contains Non-Scaling FFAG, particle accelerator capable of rapid beam acceleration, giving a pulse repetition rate of 1kHz, far beyond that of a conventional synchrotron. To realise the repetition rate, a key component of the accelerator is the rf accelerating system. The combination of a high energy gain per turn and a high repetition rate is a significant challenge. In this paper, options for the rf system of the proton ring and the status of development are presented