The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

The ASKAP-EMU Early Science Project: Radio Continuum Survey of the Small Magellanic Cloud

We present two new radio continuum images from the Australian Square Kilometre Array Pathfinder (ASKAP) survey in the direction of the Small Magellanic Cloud (SMC). These images are part of the Evolutionary Map of the Universe (EMU) Early Science Project (ESP) survey of the Small and Large Magellanic Clouds. The two new source lists produced from these images contain radio continuum sources observed at 960 MHz (4489 sources) and 1320 MHz (5954 sources) with a bandwidth of 192 MHz and beam sizes of 30.0”×30.0” and 16.3”×15.1”, respectively. The median Root Mean Squared (RMS) noise values are 186 μJy beam−1 (960 MHz) and 165 μJy beam−1 (1320 MHz). To create point source catalogues, we use these two source lists, together with the previously published Molonglo Observatory Synthesis Telescope (MOST) and the Australia Telescope Compact Array (ATCA) point source catalogues to estimate spectral indices for the whole population of radio point sources found in the survey region. Combining our ASKAP catalogues with these radio continuum surveys, we found 7736 point-like sources in common over an area of 30 deg2. In addition, we report the detection of two new, low surface brightness supernova remnant candidates in the SMC. The high sensitivity of the new ASKAP ESP survey also enabled us to detect the bright end of the SMC planetary nebula sample, with 22 out of 102 optically known planetary nebulae showing point-like radio continuum emission. Lastly, we present several morphologically interesting background radio galaxies

Food, Nutrition and Agrobiodiversity Under Global Climate Change

Available evidence and predictions suggest overall negative effects on agricultural production as a result of climate change, especially when more food is required by a growing population. Information on the effects of global warming on pests and pathogens affecting agricultural crops is limited, though crop–pest models could offer means to predict changes in pest dynamics, and help design sound plant health management practices. Host-plant resistance should continue to receive high priority as global warming may favor emergence of new pest epidemics. There is increased risk, due to climate change, to food and feed contaminated by mycotoxin-producing fungi. Mycotoxin biosynthesis gene-specific microarray is being used to identify food-born fungi and associated mycotoxins, and investigate the influence of environmental parameters and their interactions for control of mycotoxin in food crops. Some crop wild relatives are threatened plant species and efforts should be made for their in situ conservation to ensure evolution of new variants, which may contribute to addressing new challenges to agricultural production. There should be more emphasis on germplasm enhancement to develop intermediate products with specific characteristics to support plant breeding. Abiotic stress response is routinely dissected to component physiological traits. Use of transgene(s) has led to the development of transgenic events, which could provide enhanced adaptation to abiotic stresses that are exacerbated by climate change. Global warming is also associated with declining nutritional quality of food crops. Micronutrient-dense cultivars have been released in selected areas of the developing world, while various nutritionally enhanced lines are in the release pipeline. The high-throughput phenomic platforms are allowing researchers to accurately measure plant growth and development, analyze nutritional traits, and assess response to stresses on large sets of individuals. Analogs for tomorrow’s agriculture offer a virtual natural laboratory to innovate and test technological options to develop climate resilience production systems. Increased use of agrobiodiversity is crucial to coping with adverse impacts of global warming on food and feed production and quality. No one solution will suffice to adapt to climate change and its variability. Suits of technological innovations, including climate-resilient crop cultivars, will be needed to feed 9 billion people who will be living in the Earth by the middle of the twenty-first century

Towards the conservation of crop wild relative diversity in North Africa: checklist, prioritisation and inventory

Crop wild relatives (CWR) are wild species that are more or less genetically related to crops that can be used to introgress useful genes for improvement of productivity, resistance to biotic and abiotic stresses and quality of cultivated crops. They are important in crop improvement to achieve food security for an increasing population and to overcome the challenges caused by climate change and the new virulence of major diseases and pests. These genetic resources are increasingly threatened in their natural habitats through over-exploitation and land reclamation and degradation. Therefore, their efficient and effective conservation would be taxonomically and genetically valuable and will contribute to maintaining and promoting the sustainability of crop diversity, facilitating agricultural production and supporting the increasing demand for food, feed and natural resources. A checklist of 5780 Crop Wild Relatives (CWR) taxa from North Africa was obtained using the CWR Catalogue for Europe and the Mediterranean (PGR Forum). Of which consists 76% of the flora of North Africa. The checklist contains 5588 (~97%) native taxa and 192 introduced. Families with higher taxa richness are Fabaceae, Asteraceae, and Poaceae. These three families constitute more than 33% of the total taxa included in the checklist. About 9% (502) CWR taxa identified as a priority for conservation in North Africa using four criteria, the economic value of the crop, the relatedness degree of wild relatives to their crop, threat status using IUCN red list assessment, and finally the centre of origin and/or diversity of the crop. Of these, 112 taxa were assigned high, 268 medium and 122 low priorities for effective conservation. Those assessed as threatened using IUCN Red list and national assessment represent approximately 2% (119 taxa) of the CWR in the region. However, 21 taxa are assessed as critically endangered (CR), 53 as endangered (EN), and 45 as vulnerable (VU). Wild relatives of some globally important crops are present, with those related to wheat (Triticum aestivum L. and T. durum L.) and barley (Hordeum vulgare L.) among the highest priority crops for the North Africa region. Amongst CWR assessed as threatened, only 8 (6.7%) CWR are related to food crops, Avena agadiriana B.R. Baum. et G. Fedak (VU), A. atlantica B.R. Baum et G. Fedak (VU), A. murphyi Ladiz. (EN), Beta macrocarpa Guss. (EN), Olea europaea subsp. maroccana Guss. (VU), Rorippa hayanica Maire (VU) and Aegilops bicornis (Forssk.) Jaub. et Spach (VU). The wild relative of Safflower Carthamus glaucus M. Bieb is restricted to Egypt and Libya and assessed as rare in Egypt. The information available about the conservation and threat status of CWR in North Africa still lags behind, and more investigations are required