The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.

/pdf/planetary-boundaries-guiding-human-development-on-a-changing-5gmf909etg.pdf

Planetary boundaries: Guiding human development on a changing planet

We will review some of the major results in random graphs and some of the more challenging open problems. We will cover algorithmic and structural questions. We will touch on newer models, including those related to the WWW.

Random graphs

Impatti, adattamento e vulnerabilita Le cause e le responsabilita dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilita” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici.

/pdf/climate-change-2007-impacts-adaptation-and-vulnerability-31xc1cf4d3.pdf

Climate Change 2007: Impacts, Adaptation and Vulnerability.

Merchants of Doubt. How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming

Researchers have explored the benefits and applications of virtual reality (VR) in different scenarios. VR possesses much potential and its application in education has seen much research interest lately. However, little systematic work currently exists on how researchers have applied immersive VR for higher education purposes that considers the usage of both high-end and budget head-mounted displays (HMDs). Hence, we propose using systematic mapping to identify design elements of existing research dedicated to the application of VR in higher education. The reviewed articles were acquired by extracting key information from documents indexed in four scientific digital libraries, which were filtered systematically using exclusion, inclusion, semi-automatic, and manual methods. Our review emphasizes three key points: the current domain structure in terms of the learning contents, the VR design elements, and the learning theories, as a foundation for successful VR-based learning. The mapping was conducted between application domains and learning contents and between design elements and learning contents. Our analysis has uncovered several gaps in the application of VR in the higher education sphere—for instance, learning theories were not often considered in VR application development to assist and guide toward learning outcomes. Furthermore, the evaluation of educational VR applications has primarily focused on usability of the VR apps instead of learning outcomes and immersive VR has mostly been a part of experimental and development work rather than being applied regularly in actual teaching. Nevertheless, VR seems to be a promising sphere as this study identifies 18 application domains, indicating a better reception of this technology in many disciplines. The identified gaps point toward unexplored regions of VR design for education, which could motivate future work in the field.

A systematic review of immersive virtual reality applications for higher education: Design elements, lessons learned, and research agenda

Action to tackle the complex and divisive issue of climate change will be strongly influenced by public perception. Online social media and associated social networks are an increasingly important forum for public debate and are known to influence individual attitudes and behaviours – yet online discussions and social networks related to climate change are not well understood. Here we construct several forms of social network for users communicating about climate change on the popular microblogging platform Twitter. We classify user attitudes to climate change based on message content and find that social networks are characterised by strong attitude-based homophily and segregation into polarised “sceptic” and “activist” groups. Most users interact only with like-minded others, in communities dominated by a single view. However, we also find mixed-attitude communities in which sceptics and activists frequently interact. Messages between like-minded users typically carry positive sentiment, while messages between sceptics and activists carry negative sentiment. We identify a number of general patterns in user behaviours relating to engagement with alternative views. Users who express negative sentiment are themselves the target of negativity. Users in mixed-attitude communities are less likely to hold a strongly polarised view, but more likely to express negative sentiment towards other users with differing views. Overall, social media discussions of climate change often occur within polarising “echo chambers”, but also within “open forums”, mixed-attitude communities that reduce polarisation and stimulate debate. Our results have implications for public engagement with this important global challenge.

Network analysis reveals open forums and echo chambers in social media discussions of climate change

BACKGROUND: 

Genetic variations might modify associations between schizophrenia and cannabis or tobacco use.

AIMS: 

To examine whether variants within the cannabinoid receptor (CNR1) and alpha(7) nicotinic receptor (CHRNA7) genes are associated with schizophrenia, and whether these effects vary according to cannabis or tobacco use. We also examined a putative interaction between cannabis and Val(158)Met within the catechol-O-methyltransferase gene (COMT).

METHOD: 

Genotype effects of CHRNA7 and CNR1were studied in a case-control sample of 750 individuals with schizophrenia and 688 controls, with interactions for these genes studied in small subsamples. A case-only design of 493 ofthe schizophrenia group was used to examine interactions between cannabis use and COMT.

RESULTS: 

There was no evidence of association between schizophrenia and CNR1 (OR=0.97, 95% CI 0.82-1.13) or CHRNA7 (OR=1.07, 95% CI 0.77-1.49) genotypes, or of interactions between tobacco use and CHRNA7, or cannabis use and CNR1or COMT genotypes.

CONCLUSIONS: 

Neither CNR1 nor CHRNA7 variation appears to alter the risk of schizophrenia. Furthermore, our results do not support the presence of different effects of cannabis use on schizophrenia according to variation within COMT.

/pdf/genotype-effects-of-chrna7-cnr1-and-comt-in-schizophrenia-4lz7b0hibo.pdf

Genotype effects of CHRNA7, CNR1 and COMT in schizophrenia: interactions with tobacco and cannabis use

The media uses specific language to report scientific knowledge to various audiences. A study focused on broadcast, newspapers and twitter reporting of the IPCC Fifth Assessment Report shows that coverage and framing of the Report was influenced by its sequential three-part structure and by the availability of accessible narratives and visuals.

/pdf/dominant-frames-in-legacy-and-social-media-coverage-of-the-1y1of80vyj.pdf

Dominant frames in legacy and social media coverage of the IPCC Fifth Assessment Report

Another sniffer dog for the clinic

Tipping points are recognised in many systems, including ecosystems and elements of the climate system. But can the biosphere as a whole tip and, if so, how? Past global tipping points were rare and occurred in the coupled planetary-scale dynamics of the Earth system, not in the local-scale dynamics of its weakly interacting component ecosystems. Yet, evolutionary innovations have triggered past global transformations, suggesting that tipping point theory needs to go beyond bifurcations and networks to include evolution.

Hywel T. P. Williams

Papers

Network analysis reveals open forums and echo chambers in social media discussions of climate change

Genotype effects of CHRNA7, CNR1 and COMT in schizophrenia: interactions with tobacco and cannabis use

Dominant frames in legacy and social media coverage of the IPCC Fifth Assessment Report

Another sniffer dog for the clinic

On the origin of planetary-scale tipping points