687 research outputs found
More than colour attraction: behavioural functions of flower patterns
ReviewFlower patterns are thought to influence foraging decisions of insect pollinators. However, the resolution of insect compound eyes is poor. Insects perceive flower patterns only from short distances when they initiate landing or search for reward on the flower. From further away flower displays jointly form largersized patterns within the visual scene that will guide an insect’s flight behaviour. Chromatic and achromatic cues in such patterns may help insects to find, approach and learn rewarded locations in a flower patch, bringing them close enough to individual flowers. Flight trajectories and the spatial resolution of chromatic and achromatic vision in insects determine the effectiveness of floral displays, and both need to be considered in studies of plant-pollinator communication.BBSR
The impact of drought on wheat leaf cuticle properties
BACKGROUND: The plant cuticle is the outermost layer covering aerial tissues and is composed of cutin and waxes. The cuticle plays an important role in protection from environmental stresses and glaucousness, the bluish-white colouration of plant surfaces associated with cuticular waxes, has been suggested as a contributing factor in crop drought tolerance. However, the cuticle structure and composition is complex and it is not clear which aspects are important in determining a role in drought tolerance. Therefore, we analysed residual transpiration rates, cuticle structure and epicuticular wax composition under well-watered conditions and drought in five Australian bread wheat genotypes, Kukri, Excalibur, Drysdale, RAC875 and Gladius, with contrasting glaucousness and drought tolerance. RESULTS: Significant differences were detected in residual transpiration rates between non-glaucous and drought-sensitive Kukri and four glaucous and drought-tolerant lines. No simple correlation was found between residual transpiration rates and the level of glaucousness among glaucous lines. Modest differences in the thickness of cuticle existed between the examined genotypes, while drought significantly increased thickness in Drysdale and RAC875. Wax composition analyses showed various amounts of C31 ß-diketone among genotypes and increases in the content of alkanes under drought in all examined wheat lines. CONCLUSIONS: The results provide new insights into the relationship between drought stress and the properties and structure of the wheat leaf cuticle. In particular, the data highlight the importance of the cuticle’s biochemical makeup, rather than a simple correlation with glaucousness or stomatal density, for water loss under limited water conditions.Huihui Bi, Nataliya Kovalchuk, Peter Langridge, Penny J. Tricker, Sergiy Lopato, and Nikolai Borisju
The impact of monetary incentives on general fertility rates in Western Australia
Background: There has been widespread international concern about declining fertility rates and the long-term negative consequences particularly for industrialised countries with ageing populations. In an attempt to boost fertility rates, the Australian Government introduced a maternity payment known as the Baby Bonus. However, major concerns have been raised that such monetary incentives would attract teenagers and socially disadvantaged groups. Methods: Population-level data and generalised linear models were used to examine general fertility rates between 1995 and 2006 by socioeconomic group, maternal age group, Aboriginality and location in Western Australia prior to and following the introduction of the Baby Bonus in July 2004.Results: After a steady decline in general fertility rates between 1995 and 2004, rates increased significantly from 52.2 births per 1000 women, aged between 15 and 49 years, in 2004 to 58.6 births per 1000 women in 2006. While there was an overall increase in general fertility rates after adjusting for maternal socio-demographic characteristics, there were no significant differences among maternal age groups (p=0.98), between Aboriginal and non-Aboriginal women(p=0.80), maternal residential locations (p=0.98) or socioeconomic groups (p=0.68). The greatest increase in births were among women residing in the highest socioeconomic areas who had the lowest general fertility rate in 2004 (21.5 births per 1000 women) but the highest in 2006 (38.1 births per 1000 women). Conclusions: Findings suggest that for countries with similar social, economic and political climates to Australia, a monetary incentive may provide a satisfactory solution to declining general fertility rates
Neutron reflection from the liquid helium surface.
The reflection of neutrons from a helium surface has been observed for the first time. The 4He surface is smoother in the superfluid state at 1.54 K than in the case of the normal liquid at 2.3 K. In the superfluid state we also observe a surface layer ~200 Å thick which has a subtly different neutron scattering cross-section, which may be explained by an enhanced Bose-Einstein condensate fraction close to the helium surface. The application of neutron reflectometry described in this paper creates new and exciting opportunities for the surface and interfacial study of quantum fluids
An Ecological Basic Income? Examining the Ecological Credentials of Basic Income Through a Review of Selected Pilot Interventions
While basic income (BI) has long been advocated for its social benefits, some scholars also propose it in response to the ecological crises. However, the empirical evidence to support this position is currently lacking and the concept of an ecological BI (EBI) is underdeveloped. Part one of this paper attempts to develop such a concept, arguing that an EBI should seek to reduce aggregate material throughput, improve human needs satisfaction, reduce inequalities, rebalance productive activity towards social activities in the autonomous sphere, and promote societal values of cooperation and sufficiency. Part two examines how BI interventions consider the principles of an EBI in their designs and discusses what their findings infer about BI’s ecological credentials. The results find that while ecological considerations are largely absent from BI intervention designs, their findings suggest that interventions aligned with the principles of an EBI could play a role in addressing the ecological crises
Mental health of veterinary nurses and student veterinary nurses: A scoping review
Background: Research has found veterinarians around the world to be at high risk of mental health problems, but far less research has examined veterinary nurses (VNs) and student veterinary nurses (SVNs). This scoping review aimed to map existing evidence on this topic, and identify knowledge gaps.
Methods: Literature searches of MEDLINE, PsycINFO, PubMed, Web of Science, and Google Scholar were conducted, and a structured screening and selection procedure applied. To be included, studies had to be peer-reviewed, report relevant results specific to VNs and/or SVNs, and provide descriptive statistics if using quantitative methods.
Results: Of 2,118 publications identified, only 13 journal articles met the inclusion criteria. The findings were summarised in five categories: mental health and wellbeing; burnout; stress; compassion fatigue; and moral distress. While the findings of five of the studies suggested that some VNs and SVNs experienced some form of poor mental health, these lacked generalisability or transferability for multiple reasons. There was also inconsistency and ambiguity in the interpretation of findings, and incompatible or oversimplified definitions of mental health problems.
Conclusions: More research is needed to address the gaps in existing evidence supporting our understanding of VN and SVN mental health. This should establish baseline measures, and include comparisons with other occupational and national populations
Coordinated regulation of enzymes involved in secondary cell wall biosynthesis by a homeodomain transcription factor
Probing the Spiral Magnetic Phase in 6 nm Textured Erbium using Polarised Neutron Reflectometry
We characterise the magnetic state of highly-textured, sputter deposited erbium for a film of thickness 6 nm. Using polarised neutron reflectometry it is found the film has a high degree of magnetic disorder, and we present some evidence that the films’ local magnetic state is consistent with bulk-like spiral magnetism. This, combined with complementary characterisation techniques, show that thin film erbium is a strong candidate material for incorporation into device structures
Generation of drought-resistant transgenic cereals using transcription factors isolated from wheat grain
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