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1.
PLoS One ; 16(4): e0249993, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909643

RESUMO

Ever since the web began, the number of websites has been growing exponentially. These websites cover an ever-increasing range of online services that fill a variety of social and economic functions across a growing range of industries. Yet the networked nature of the web, combined with the economics of preferential attachment, increasing returns and global trade, suggest that over the long run a small number of competitive giants are likely to dominate each functional market segment, such as search, retail and social media. Here we perform a large scale longitudinal study to quantify the distribution of attention given in the online environment to competing organisations. In two large online social media datasets, containing more than 10 billion posts and spanning more than a decade, we tally the volume of external links posted towards the organisations' main domain name as a proxy for the online attention they receive. We also use the Common Crawl dataset-which contains the linkage patterns between more than a billion different websites-to study the patterns of link concentration over the past three years across the entire web. Lastly, we showcase the linking between economic, financial and market data by exploring the relationships between online attention on social media and the growth in enterprise value in the electric carmaker Tesla. Our analysis shows that despite the fact that we observe consistent growth in all the macro indicators-the total amount of online attention, in the number of organisations with an online presence, and in the functions they perform-we also observe that a smaller number of organisations account for an ever-increasing proportion of total user attention, usually with one large player dominating each function. These results highlight how evolution of the online economy involves innovation, diversity, and then competitive dominance.


Assuntos
Marketing/economia , Navegador/economia , Evolução Cultural , Humanos , Indústrias/economia , Mídias Sociais/economia
2.
Drug Alcohol Depend ; 217: 108254, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979736

RESUMO

BACKGROUND: Personal vaporisers are gaining popularity as an alternative route of administration for a range of substances. Online cryptomarkets are becoming increasingly popular among people who use substances due to their perceived anonymity, ease of use, and reduced risk of violence compared to traditional face-to-face dealers. We examined the diversity of substances marketed for use in a personal vaporiser on these marketplaces. METHODS: Vaping related listings were extracted from three online cryptomarkets ('Agartha', 'Cryptonia', and 'Tochka') using The Onion Router browser. Data collection occurred between October and November 2019. RESULTS: We identified 1929 listings from 201 unique sellers. The top product on Agartha, Cryptonia, and Tochka were vape cartridges prefilled with the e-liquid (70.4 %, 39.4 %, 52.3 % respectively). The most common substance in these products was cannabis oil (96.1 %, 82.1 %, 87.8 %), followed by synthetic cannabinoids (3.7 %, 9.7 %, 9.8 %) and psychedelic substances (0.2 %, 6.4 %, 1.2 %). Vendors were primarily from the USA. Many products offered worldwide shipping (96.3 %, 42.4 %, 51.2 %). CONCLUSION: Vaping products listed on online cryptomarkets in 2019 primarily contained cannabis oils. Future studies should continue to examine cryptomarkets to identify emerging trends of substances that can be used in personal vaporisers.


Assuntos
Comércio/economia , Sistemas Eletrônicos de Liberação de Nicotina/economia , Fumar Maconha/economia , Nebulizadores e Vaporizadores/economia , Vaping/economia , Navegador/economia , Comércio/tendências , Coleta de Dados/tendências , Tráfico de Drogas/economia , Tráfico de Drogas/tendências , Alucinógenos/administração & dosagem , Alucinógenos/economia , Humanos , Drogas Ilícitas/economia , Fumar Maconha/tendências , Marketing/economia , Marketing/tendências , Nebulizadores e Vaporizadores/tendências , Navegador/tendências
3.
Brief Bioinform ; 20(4): 1215-1221, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-29092005

RESUMO

Sustainable noncommercial bioinformatics infrastructures are a prerequisite to use and take advantage of the potential of big data analysis for research and economy. Consequently, funders, universities and institutes as well as users ask for a transparent value model for the tools and services offered. In this article, a generally applicable lightweight method is described by which bioinformatics infrastructure projects can estimate the value of tools and services offered without determining exactly the total costs of ownership. Five representative scenarios for value estimation from a rough estimation to a detailed breakdown of costs are presented. To account for the diversity in bioinformatics applications and services, the notion of service-specific 'service provision units' is introduced together with the factors influencing them and the main underlying assumptions for these 'value influencing factors'. Special attention is given on how to handle personnel costs and indirect costs such as electricity. Four examples are presented for the calculation of the value of tools and services provided by the German Network for Bioinformatics Infrastructure (de.NBI): one for tool usage, one for (Web-based) database analyses, one for consulting services and one for bioinformatics training events. Finally, from the discussed values, the costs of direct funding and the costs of payment of services by funded projects are calculated and compared.


Assuntos
Biologia Computacional/economia , Biologia Computacional/métodos , Software/economia , Big Data/economia , Biologia Computacional/educação , Consultores , Custos e Análise de Custo , Arquitetura de Instituições de Saúde/economia , Humanos , Serviços de Informação/economia , Modelos Econômicos , Navegador/economia
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