Blockchain and certificate authority cryptography for an asynchronous on-line public notary system

The true innovation behind the Bitcoin protocol is blockchain technology. Blockchain is the underlying distributed database and encryption technology that enables trustless transactions that can be verified, monitored, and enforced without a central institution. This master’s report presents the core concepts behind blockchain that are concerned with carrying instructions for storage, sharing of non-financial data, including an examination of the byzantine fault tolerant cryptography model. A literature review describes the types of blockchains, nodes, proof of work, disadvantages, and risks and provides a survey of future applications related to state government records, such as birth certificates, automobile registrations, land deeds, and voting. This review will answer the question: Is it possible for a state government to use blockchain employing trusted nodes given that the nature of blockchain is that of a distributed network of peers accompanied by a public ledger without a central authority? Finally, the requirements for a specific application case study will be defined and developed. The desired application will be a smart contract to invoke a statutory durable power of attorney using blockchain technology for oneself in case of incapacitation while still living.Electrical and Computer Engineerin

Increasing aridity reduces soil microbial diversity and abundance in global drylands

Artículo de publicación ISISoil bacteria and fungi play key roles in the functioning of terrestrial ecosystems, yet our understanding of their responses to climate change lags significantly behind that of other organisms. This gap in our understanding is particularly true for drylands, which occupy similar to 41% of Earth ' s surface, because no global, systematic assessments of the joint diversity of soil bacteria and fungi have been conducted in these environments to date. Here we present results from a study conducted across 80 dryland sites from all continents, except Antarctica, to assess how changes in aridity affect the composition, abundance, and diversity of soil bacteria and fungi. The diversity and abundance of soil bacteria and fungi was reduced as aridity increased. These results were largely driven by the negative impacts of aridity on soil organic carbon content, which positively affected the abundance and diversity of both bacteria and fungi. Aridity promoted shifts in the composition of soil bacteria, with increases in the relative abundance of Chloroflexi and alpha-Proteobacteria and decreases in Acidobacteria and Verrucomicrobia. Contrary to what has been reported by previous continental and global-scale studies, soil pH was not a major driver of bacterial diversity, and fungal communities were dominated by Ascomycota. Our results fill a critical gap in our understanding of soil microbial communities in terrestrial ecosystems. They suggest that changes in aridity, such as those predicted by climate-change models, may reduce microbial abundance and diversity, a response that will likely impact the provision of key ecosystem services by global drylands.European Research Council (ERC) under European Community 242658 Spanish Ministry of Economy and Competitiveness BIOMOD Project CGL2013-44661-R Australian Research Council DP13010484 Salvador de Madariaga program of the Spanish Ministry of Education, Culture and Sports Grant PRX14/00225 Research Exchange Program of the Hawkesbury Institute for the Environment Alexander Von Humboldt Foundation Iniciativa Cientifica Milenio (MIDEPLAN) PO5-002 Comision Nacional de Investigacion Cientifica y Tecnologica PFB-2

Tríptico

En este documental, Producido por la ENS, reconstruye las vidas de tres líderes sindicales de ADIDA, cuyas historias cuentan la violencia antisindical que sufre el magisterio en Colombia.ENS VIDEO

Plant Species Richness and Ecosystem Multifunctionality in Global Drylands

Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands