Water use, water use efficiency, water soluble carbohydrate and yield of four varieties of wheat in continuously high temperatures

High temperatures are a common feature of the environment of tropical regions such as Lombok Island and although the effect can be alleviated by altitude, heat stress will be an important limitation to the productivity of wheat in this environment. The objectives of the experiment were to observe the responses of water use (WU), water use efficiency (WUE) and water soluble carbohydrate (WSC) to high temperatures on growth and yield of wheat under controlled conditions. In this experiment plants were grown under growth chambers at temperatures to simulate low and high elevation locations on Lombok Island. Water use, water use efficiency, WSC and yield of 4 wheat genotypes (2 Australian and 2 Indonesian varieties) grown at 3 temperatures (32°/23°C, 28°/20ºC, and 25°/15ºC day/night) were compared. Variation in water use, water use efficiency, and the concentration of water soluble carbohydrate was found. Indonesian wheat varieties, Nias and Dewata produced higher yield and biomass and maintaining higher rates of water use and remobilisation of water soluble carbohydrate from vegetative tissues to grain. The accumulation of water soluble carbohydrates was an important adaptive characteristic that was strongly associated with grain weight and grains per spikelet and maintained better yield.A Zubaidi, D R Anugrahwati, G Gill and G K McDonal

Yield and photosynthetic rate of wheat under continuously high temperature

In tropical regions high temperature occurs throughout wheat growth cycle and is a major factor influencing growth and yield in this area. The aim of this work is to describe the responses to continuously-high temperatures on growth, photosynthesis and yield of wheat, under controlled conditions. Nias and Dewata (Indonesian wheat varieties) and Axe and Gladius (Australian varieties) were tested in growth room experiment with temperature and photoperiod chosen to simulate conditions on Lombok Island, at lowland (32/23°C) and highland (28/20°C) sites. The third temperature (25/15°C) was selected to represent temperature in a more temperate wheat-producing area. High temperature reduced yield and dry matter accumulation which was associated with a reduction in photosynthetic rate and stomata conductance and an increase in respiration rate. The reduction in photosynthetic rate at high temperature was not only due to lower stomatal conductance but also non-stomatal effects as mesophyll conductance and quantum yield were lower. Genetic variability in response to heat stress was evident with the Indonesian varieties being more tolerant to high temperatures than Australian varieties. Nias and Dewata produced higher yield and biomass and maintaining higher rates of photosynthesis. Maintaining high photosynthetic rate and high stomata conductance, are important characters in adapting wheat into tropical environment such as Lombok Island.A Zubaidi, D R Anugrahwati, G K McDonald and G Gil

A decoy receptor 3 analogue reduces localised defects in phagocyte function in pneumococcal pneumonia

Background. Therapeutic strategies to modulate the host response to bacterial pneumonia are needed to improve outcomes during community-acquired pneumonia. This study used mice with impaired Fas signalling to examine susceptibility to pneumococcal pneumonia and decoy receptor 3 analogue (DcR3-a) to correct factors associated with increased susceptibility. Methods. Wild-type mice and those with varying degrees of impairment of Fas (lpr) or Fas ligand signalling (gld) were challenged with Streptococcus pneumoniae and microbiological and immunological outcomes measured in the presence or absence of DcR3-a. Results. During established pneumonia, neutrophils became the predominant cell in the airway and gld mice were less able to clear bacteria from the lungs, demonstrating localised impairment of pulmonary neutrophil function in comparison to lpr or wild-type mice. T-cells from gld mice had enhanced activation and reduced apoptosis in comparison to wild-type and lpr mice during established pneumonia. Treatment with DcR3-a reduced T-cell activation and corrected the defect in pulmonary bacterial clearance in gld mice. Conclusions. The results suggest that imbalance in tumour necrosis factor superfamily signalling and excessive T-cell activation can impair bacterial clearance in the lung but that DcR3-a treatment can reduce T-cell activation, restore optimal pulmonary neutrophil function and enhance bacterial clearance during S pneumoniae infection

Should social enterprises complement or supplement public health provision?

Purpose This paper explores how stable employment, company culture, and tailored health, digital, and core skills training provided by a social enterprise (SE) in the Philippines affect survivors of exploitation. Research shows survivors experience adverse social conditions and physical and mental health outcomes caused by their exploitative experience. Stable, decent employment has been identified as critical to their recovery and reintegration. This paper discusses the SE’s impact on the employees’ physical, mental, and social health and behaviour. Based on our findings, we discuss the contribution of SE in improving health outcomes and providing health services, and conclude that SEs should not replace but complement public health government programmes. Design/methodology/approach This paper uses mixed methods, presenting data from a longitudinal survey (household income, mental health, and social wellbeing, among others), and a follow-up qualitative study, which uses in-depth interviews and participatory videos to explore survey findings. Findings The quantitative analysis demonstrates positive, but gradual, changes in sexual and reproductive health behaviour; personal empowerment; and trauma, anxiety, and depressive symptoms. The qualitative findings show how improvements in executive functioning, self-regulation, and self-esteem occur incrementally over time. As their self-efficacy improves, employees need to avoid being overly dependent on the SE, to support their autonomy, therefore access to complementary public health services is fundamental. Originality/value This paper focuses, to our knowledge, on a unique SE, which hires survivors of exploitation, without losing their competitiveness in the market

Photoionisation loading of large Sr+ ion clouds with ultrafast pulses

This paper reports on photoionisation loading based on ultrafast pulses of singly-ionised strontium ions in a linear Paul trap. We take advantage of an autoionising resonance of Sr neutral atoms to form Sr+ by two-photon absorption of femtosecond pulses at a wavelength of 431nm. We compare this technique to electron-bombardment ionisation and observe several advantages of photoionisation. It actually allows the loading of a pure Sr+ ion cloud in a low radio-frequency voltage amplitude regime. In these conditions up to 4x10^4 laser-cooled Sr+ ions were trapped

A weakly stable algorithm for general Toeplitz systems

We show that a fast algorithm for the QR factorization of a Toeplitz or Hankel matrix A is weakly stable in the sense that R^T.R is close to A^T.A. Thus, when the algorithm is used to solve the semi-normal equations R^T.Rx = A^Tb, we obtain a weakly stable method for the solution of a nonsingular Toeplitz or Hankel linear system Ax = b. The algorithm also applies to the solution of the full-rank Toeplitz or Hankel least squares problem.Comment: 17 pages. An old Technical Report with postscript added. For further details, see http://wwwmaths.anu.edu.au/~brent/pub/pub143.htm

Antihydrogen formation dynamics in a multipolar neutral anti-atom trap

Antihydrogen production in a neutral atom trap formed by an octupole-based magnetic field minimum is demonstrated using field-ionization of weakly bound anti-atoms. Using our unique annihilation imaging detector, we correlate antihydrogen detection by imaging and by field-ionization for the first time. We further establish how field-ionization causes radial redistribution of the antiprotons during antihydrogen formation and use this effect for the first simultaneous measurements of strongly and weakly bound antihydrogen atoms. Distinguishing between these provides critical information needed in the process of optimizing for trappable antihydrogen. These observations are of crucial importance to the ultimate goal of performing CPT tests involving antihydrogen, which likely depends upon trapping the anti-atom

Search For Trapped Antihydrogen

We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 10^7 antiprotons with 1.3 10^9 positrons to produce 6 10^5 antihydrogen atoms, we have identified six antiproton annihilation events that are consistent with the release of trapped antihydrogen. The cosmic ray background, estimated to contribute 0.14 counts, is incompatible with this observation at a significance of 5.6 sigma. Extensive simulations predict that an alternative source of annihilations, the escape of mirror-trapped antiprotons, is highly unlikely, though this possibility has not yet been ruled out experimentally.Comment: 12 pages, 7 figure

Topological Defects and CMB anisotropies : Are the predictions reliable ?

We consider a network of topological defects which can partly decay into neutrinos, photons, baryons, or Cold Dark Matter. We find that the degree-scale amplitude of the cosmic microwave background (CMB) anisotropies as well as the shape of the matter power spectrum can be considerably modified when such a decay is taken into account. We conclude that present predictions concerning structure formation by defects might be unreliable.Comment: 14 pages, accepted for publication in PR