Eris was a very important discovery in 2005. Since it was larger than Pluto, some astronomers thought it should be considered a planet. However, since Pluto and Eris are located in an asteroid belt, other astronomers began to think maybe Pluto and Eris were both very large asteroids. In 2006, Astronomers decided it was time to update the current definition of a planet and create the new category of dwarf planets.
Climate change has caught great attention. Ecological systems co-evolve with climate systems, thus, understanding the intrinsic dynamics of ecological systems is of paramount importance for exploring and predicting climate change. Food chains, as a systematic and simplistic model, have been a paradigm for investigating the long-term evolution of ecological systems in virtue of the dynamical analysis on the inter-play between the topology and the dynamical processes occurring in a food chain. We build a food chain model by considering energy exchanges among species, which is characterized by using population dynamical equations. We will compare our model with existing food chain models based on sufficiently empirical data. Our work is expected to be able to quantitatively capture and describe the interactions among species with respect to energy exchange, then deepen the understanding of ecological systems and their coevolution with climate change.
The challenges of collective action are presented by leaders in many industrialized countries as a major obstacle to effective action on climate change. Notably, the argument goes, a fair international solution must appropriately constrain large greenhouse gas emitters like China. This paper asks whether citizen support for multilateral climate policies also depends on whether other countries are seen to reciprocate. We analyze results from population-based survey experiments in the US, Canada, Norway, and Sweden, asking subjects whether they think their country should commit internationally to emission reductions. Randomly assigned sub-samples were presented with statements suggesting that China may or may not choose to cooperate, or alternatively making no mention of China. We find that reciprocity is important to respondents in the smaller Scandinavian countries but not in North America. These findings suggest that country size is more important than national traditions of multilateral cooperation in predicting support for unilateral climate action.
The symbiosis between corals and Symbiodinium dinoflagellates is considered a major driver of the distribution and health of reefs worldwide. This study investigated the genetic identities and diversity of Symbiodinium in seven coral species (Porites lutea, Porites lobata, Acropora millepora, Merulina ampliata, Diploastrea heliopora, Pachyseris speciosa, Pocillopora acuta) from three shallow reefs around Singapore (Kusu Island, Pulau Tekukor, Pulau Satumu). Analyses of 31 colonies using denaturing gradient gel electrophoresis of the nuclear internal transcribed spacer region indicated the dominance of C and D Symbiodinium clades. The latter clade was the predominant symbiont in Pachyseris speciosa collected from Pulau Tekukor but those sampled from Pulau Satumu hosted C27, providing evidence for variable symbiosis in this species. The prevalence of the D clade – noted for their stress tolerance (e.g. to elevated temperatures and sedimentation) – in three of seven coral species examined could underlie the importance of this particular symbiotic relationship for the persistence of Singapore’s impacted reefs. Further characterisation of Symbiodinium communities may provide insights into corals’ response to stress and their bleaching patterns in the future.
Human consumption of fish has been trending upwards in the past decades and this is projected to continue. The main sources of fish are from wild fisheries (marine and freshwater) and aquaculture. Climate change is anticipated to affect the availability of fish through its effect on these two sources as well as on supply chain processes such as storage, transport, processing and retail. Climate change is known to result in warmer and more acid oceans. Ocean acidification due to higher CO2 concentration levels at sea modifies the distribution of phytoplankton and zooplankton to affect wild, capture fisheries. Higher temperature causes warm-water coral reefs to respond with species replacement and bleaching, leading to coral cover loss and habitat loss. Global changes in climatic systems may also cause fish invasion, extinction and turnover. While this may be catastrophic for small scale fish farming in poor tropical communities, there are also potential effects on animal protein supply shifts at local and global scales with food security consequences. This paper discusses the potential impacts of climate change on fisheries and aquaculture in the Asian Pacific region, with special emphasis on Southeast Asia. The key question to be addressed is “What are the impacts of global climate change on global fish harvests and what does it mean to the availability of fish?”
This paper provides an overview of food waste in the context of food security, resources management and environment health. It compares approaches taken by various governments, community groups, civil societies and private sector organisations to reduce food waste in the developed and developing countries. What constitutes ‘food waste’ is not as simple as it may appear due to diverse food waste measurement protocols and different data documentation methods used worldwide. There is a need to improve food waste data collection methods and implementation of effective strategies, policies and actions to reduce food waste. Global initiatives are urgently needed to: enhance awareness of the value of food; encourage countries to develop policies that motivate community and businesses to reduce food waste; encourage and provide assistance to needy countries for improving markets, transport and storage infrastructure to minimise food waste across the value chain; and, develop incentives that encourage businesses to donate food. In some countries, particularly in Europe, initiatives on food waste management have started to gain momentum. Food waste is a global problem and it needs urgent attention and integrated actions of stakeholders across the food value chain to develop global solutions for the present and future generations.
Fish is one of the major sources of animal protein. Due to rising world populations, increasing income and urbanization, demand for fish has been increasing. In order to meet the need for more fish, aquaculture has become increasingly important as wild populations and production from capture fisheries have declined due to overfishing and poor management. In recent years, production from aquaculture has increased rapidly to address the shortfalls in capture fisheries, especially in Asia where aquaculture production accounts for about 90% of world aquaculture production by volume. This paper reviews the status of the world’s fish production, provides an update on Asian aquaculture, and highlights developments that are contributing to sustainable fish production, particularly integrated multi-trophic aquaculture and aquaponics.
The world’s population continues to expand and it is expected to cross 9 billion by 2050. This would significantly amplify the demand for food, which will pose serious threats to global food security. Additional challenges are being imposed due to a gradual decrease in the total arable land and global environmental changes. Hence, it is of utmost importance to review and revise the existing food production strategies by incorporating novel biotechnological approaches that can help to break the crop yield barriers in the near future. In this review, we highlight some of the concerns hampering crop yield enhancements. The review also focuses on modern breeding techniques based on genomics as well as proven biotechnological approaches that enable identification and utilization of candidate genes. Another aspect of discussion is the important area of research, namely hormonal regulation of plant development, which is likely to yield valuable regulatory genes for such crop improvement efforts in the future. These strategies can serve as potential tools for developing elite crop varieties for feeding the growing billions.
Food safety and food security are interrelated concepts with a profound impact on the quality of human life. Food security describes the overall availability of food at different levels from global to individual household. While, food safety focuses on handling, preparation and storage of foods in order to prevent foodborne illnesses. This review focuses on innovative thermal and non-thermal technologies in the area of food processing as the means to ensure food security through improving food safety with emphasis on the reduction and control of microbiological risks. The antimicrobial efficiency and mechanism of new technologies to extend the shelf life of food product were also discussed.
Food security is a complex phenomenon made up of multiple dimensions — food availability, physical access to food, economic access to food, food utilization — each of which has a stability dimension which underpins it. This review provides details on these dimensions and links them to two published indices which provide assessments of the state of food security in a country. The paper further provides analyses of the main supply and demand factors in the food security equation. Food security faces natural and anthropogenic threats such as loss of productive land and water, climate change and declining crop productivity, all of which are potentially amenable to solutions provided by science and technology. Demographic and accompanying diet changes further exacerbate the demands made on the natural resource base for food production. Finally, possible responses to the challenges confronting a secured food future are discussed from technological, policy and system level perspectives.
Vegetables that contain most of the essential components of human nutrition are perishable and cannot be stocked. To secure vegetable supply in space limited cities such as Singapore, there are different farming methods to produce vegetables. These include low-cost urban community gardening and innovative rooftop and vertical farms integrated with various technologies such as hydroponics, aquaponics and aeroponics. However, for large-scale vegetable production in space-limited Singapore, we need to develop farming systems that not only increase productivity many-fold per unit of land but also produce all types of vegetable, all year-round for today and the future. This could be resolved through integrated vertical aeroponic farming system. Manipulation of root-zone (RZ) environments such as cooling the RZ, modifying mineral nutrients and introducing elevated RZ CO2 using aeroponics can further boost crop productivity beyond what can be achieved from more efficient use of land area. We could also adopt energy saving light emitting diodes (LEDs) for vertical aeroponic farming system to promote uniform growth and to improve the utilisation of limited space via shortening the growth cycle, thus improving vegetable production in a cost-effective manner.
COSMOSVol. 10, No. 01, pp. 9-12 (2014) Research ArticlesNo AccessSAFE AND EFFICIENT REPROGRAMMING OF SOMATIC CELLS INTO STEM CELLS IN LIVING TISSUEYIN KWAN WONG and THILO HAGENYIN KWAN WONGDepartment of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 117599, Singapore and THILO HAGENDepartment of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 117599, Singaporehttps://doi.org/10.1142/S0219607714400023Cited by:0 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail Keywords:In vivo gene deliveryinduced pluripotentsystem cellsin vivo programming References 1. M Abad, L Mosteiro, C Pantoja, M Cañamero, T Rayon and et al., Reprogramming in vivo produces teratomas and iPS cells with totipotency features, Nature 502 (2013) 340–345. Crossref, Google Scholar2. 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Be inspired by these Popular Science books!Includes all-time bestsellers and new titles FiguresReferencesRelatedDetails Recommended Vol. 10, No. 01 Metrics History Received 6 January 2014 Revised 4 March 2014 Accepted 27 March 2014 Published: 13 February 2015 KeywordsIn vivo gene deliveryinduced pluripotentsystem cellsin vivo programmingPDF download
Mitochondria are indispensable in cellular functions such as energy production and death execution. They are emerging as intriguing therapeutic target as their dysregulation was found to be monumental in diseases such as neurodegenerative disease, obesity, and cancer etc. Despite tremendous interest being focused on therapeutically intervening mitochondrial function, few mito-active drugs were successfully developed, particularly due to challenges in delivering active compound to this organelle. In this review, effort in utilizing nanotechnology for targeted mitochondrial delivery of compound is expounded based on the nature of the nanomaterial used. The advantage and potential offered are discussed alongside the limitation. Finally the review is concluded with perspectives of the application of nanocarrier in mitochondrial medicine, given the unresolved concern on potential complications.
