1,073 research outputs found
The structure and possible origins of stacking faults in gamma-yttrium disilicate
Parallel stacking faults on (010) planes are frequently observed in hot-pressed Y2Si2O7. A combination of conventional dark-field imaging and high-resolution transmission electron microscopy was used to investigate the structure of these faults and it was found that they consist of the repeat of one layer of the two layer γ-Y2Si2O7 structure with an associated in-plane rigid body displacement. The resulting structure was confirmed by image simulation of high-resolution images from two perpendicular projections. A model for the formation of the stacking faults is proposed as a consequence of a transformation from β-Y2Si2O7 to γ-Y2Si2O7 in the hot pressing
Detection of flying-foxes using automated audio recorders
Flying-foxes are little understood in Australia largely due to their extreme mobility. This mobility is particularly evident in the two species (spectacled and little red) found across the north of Australia, where huge numbers of animals will suddenly converge on a region and then leave a few weeks later. To improve management of these species we need to understand the movement and ecology of the animals and this is not straightforward as the camps are often remote and inaccessible.
In this project we aimed to test the viability of using automated acoustic recorders for determining the presence of spectacled flying-foxes at camp locations. A Song Meter SM4 recorder was used to record flying-foxes in a number camps around South East QLD/Northern Rivers (black and grey-headed flying-foxes) and Cairns (spectacled flying-fox). A total of 35 hour of flying-foxes calls were recorded over a period of 8 weeks from August to October 2017.
The recordings were processed using a Binary Winnow classifier and Hidden Markov Model in Kaleidoscope Software (Wildlife Acoustics). Tagged one-minute recordings were used to train the Hidden Markov Model in Kaleidoscope which was subsequently used in classifying the remaining recordings.
Using this approach, we were able to quickly and easily detect the presence of flying-foxes in the acoustic recordings. In this way, ecologists can easily implement projects for long-term monitoring of flying-fox populations using remotely deployed acoustic recorders. It may also assist management agencies for urban planning in northern Australia. For future work, we will be investigate advanced machine learning algorithms coupled with flying-fox behavioural call patterns to attempt to distinguish the species of flying-fox from acoustic recordings
Occupant Plugload Management for Demand Response in Commercial Buildings: Field Experimentation and Statistical Characterization
Commercial buildings account for approximately 36% of US electricity
consumption, of which nearly two-thirds is met by fossil fuels [1] resulting in
an adverse impact on the environment. Reducing this impact requires improving
energy efficiency and lowering energy consumption. Most existing studies focus
on designing methods to regulate and reduce HVAC and lighting energy
consumption. However, few studies have focused on the control of occupant
plugload energy consumption. In this study, we conducted multiple experiments
to analyze changes in occupant plugload energy consumption due to monetary
incentives and/or feedback. The experiments were performed in government office
and university buildings at NASA Research Park located in Moffett Field, CA.
Analysis of the data reveal significant plugload energy reduction can be
achieved via feedback and/or incentive mechanisms. Autoregressive models are
used to predict expected plugload savings in the presence of exogenous
variables. The results of this study suggest that occupant-in-the-loop control
architectures have the potential to reduce energy consumption and hence lower
the carbon footprint of commercial buildings.Comment: 20 pages, 15 figures, 4 tables, preprin
The Disappearance of Moral Choice in Serially Reproduced Narratives
How do narratives influence moral decision-making? Our ongoing studies
use serial reproduction of narratives, that is multiple retellings as
in the telephone game, of morally ambiguous situations. In particular,
we tested stories that include a minor misdemeanor, but leave open
whether the wrongdoer will be punished by a bystander. It turns out
that serial reproduction (retelling) of stories tends to eliminate the
possibility of intervention by the bystander under certain conditions.
We reason that this effect can be explained either by preferences of
the readers or by the reader\u27s discomfort to get involved. A second
finding is that retellings of third-person narratives of moral
situations lead to a higher degree of change and invention of the
outcome than first-person narratives
Ostracism and fines in a public goods game with accidental contributions: The importance of punishment type
Punishment is an important method for discouraging uncooperative behavior. We use a novel design for a public goods game in which players have explicit intended contributions with accidentally changed actual contributions, and in which players can apply costly fines or ostracism. Moreover, all players except the subject are automated, whereby we control the intended contributions, actual contributions, costly fines, and ostracisms experienced by the subject. We assess subject’s utilization of other players’ intended and actual contributions when making decisions to fine or ostracize. Hierarchical Bayesian logistic regression provides robust estimates. We find that subjects emphasize actual contribution more than intended contribution when deciding to fine, but emphasize intended contribution more than actual contribution when deciding to ostracize. We also find that the efficacy of past punishment, in terms of changing the contributions of the punished player, influences the type of punishment selected. Finally, we find that the punishment norms of the automated players affect the punishments performed by the subject. These novel paradigms and analyses indicate that punishment is flexible and adaptive, contrary to some evolutionary theories that predict inflexible punishments that emphasize outcomes
Human embryo models: the importance of national policy and governance review
Integrated and non-integrated stem cell-based models of human embryos (SCB-EMs) are becoming widely adopted tools in biomedical research with distinct advantages over animal models for studying human development. Although SCB-EMs have tremendous benefits for research, they raise a number of social, ethical and legal questions which affect future research and widespread adoption in industry and clinical settings. The 2021 ISSCR guidelines for Stem Cell Research and Clinical Translation provide helpful guidance on many of these issues but do not have force in domestic law. Careful appraisal and development of national legal and ethical frameworks is crucial. Paving the way to better regulation provides an ethical and social foundation to continue using human embryo models and to fully realise their potential benefits for reproductive medicine
Molecular determinants of a competent bovine corpus luteum: first vs final wave dominant follicles
Reproductive management in cattle requires the synchrony of follicle development and oestrus before insemination. However, ovulation of follicles that have not undergone normal physiological maturation can lead to suboptimal luteal function. Here, we investigated the expression of a targeted set of 47 genes in (a) a first-wave vs final-wave dominant follicle (DF; the latter destined to ovulate spontaneously) and (b) 6-day-old corpora lutea (CLs) following either spontaneous ovulation or induced ovulation of a first-wave DF to ascertain their functional significance for competent CL development. Both the mass and progesterone-synthesising capacity of a CL formed following induced ovulation of a first-wave DF were impaired. These impaired CLs had reduced expression of steroidogenic enzymes (e.g. STAR and HSD3B1), luteotrophic receptors (LHCGR) and angiogenic regulators (e.g. VEGFA) and increased expression of BMP2 (linked to luteolysis). Relative to final-wave DFs, characteristic features of first-wave DFs included reduced oestradiol concentrations and a reduced oestradiol:progesterone ratio in the face of increased expression of key steroidogenic enzymes (i.e. CYP11A1, HSD3B1 and CYP19A1) in granulosa cells and reduced expression of the HDL receptor SCARB1 in thecal cells. Transcripts for further components of the TGF and IGF systems (e.g. INHA, INHBA, IGF2R and IGFBP2) varied between the first- and final-wave DFs. These results highlight the importance of hormones such as progesterone interacting with local components of both the TGF and IGF systems to affect the maturation of the ovulatory follicle and functional competency of the subsequent CL
Synthesis and Assembly of Nonspherical Hollow Silica Colloids Under Confinement
Hard peanut-shaped colloids were synthesized and organized into a degenerate crystal (DC), a phase previously observed only in simulations. In this structure, particle lobes tile a triangular lattice while their orientations uniformly populate the three underlying crystalline directions
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