This work shows the results of the biosynthesis of silver nanoparticles using the microalga Chlorella sp, using growth media with different concentrations of glycerol, between 5%–20%, and different light and temperature conditions. The synthesis of nanoparticles was studied using supernatants and pellets from autotrophic, heterotrophic and mixotrophic cultures of the microalga. The presence of nanoparticles was verified by ultraviolet-visible spectroscopy and the samples showing the highest concentration of nanoparticles were characterized by scanning electron microscopy. The mixotrophic growth conditions favored the excretion of exopolymers that enhanced the reduction of silver and thus the formation of nanoparticles. The nanoparticles obtained presented predominantly ellipsoidal shape with dimensions of 108 nm × 156 nm and 87 nm × 123 nm for the reductions carried out with the supernatants of the mixotrophic cultures with 5% and 10% glycerol, respectively.

The wealth of nations depends on the quality of their infrastructure. Often, however, infrastructure suffers from ineffective investments and poor maintenance. Proposed solutions, such as New Public Management or Public-Private Partnerships (PPPs) tend to develop into Politicians-Private Partnerships as politicians collude with private firms to exploit present and future tax-payers. Therefore, it is necessary to give citizens better control over collective decision making. While there is a significant economic literature on empowering citizens via decentralization and direct democratic institutions, the role of electoral rules has thus far been rather neglected. An interesting case in point is Switzerland, which is well known for its high-quality infrastructure, extensive decentralization, and direct democracy. However, this paper argues that there is an additional and previously neglected institution that moves Swiss politicians away from client politics towards better serving public interest: Switzerland’s unique electoral institutions which effectively combine proportional elections with multi-seat majority elections. We explain how these institutions work, how they enhance the relationships between citizens and public and private entities, and we argue that they could be implemented in other countries.

The Belt and Road Initiative (BRI) aims to enhance connectivity and collaboration among 60 countries and beyond in Asia, Africa and Europe. Information and communications technology (ICT) is an indispensable component of the initiative, critical in providing fundamental communication channels for global financial transactions, trade exchanges and transport and energy connectivity, and socio cultural collaboration and scientific exchanges between people, organizations and countries along the BRI corridors. Previously constrained by infrastructure deficits in ICT, the Asia-Pacific region is accelerating its efforts to provide reliable and affordable broadband networks throughout the region, to contribute to successful implementation of the Sustainable Development Goals (SDG).

Within the BRI corridors, this study which has been undertaken as part of the research programme of the United Nations Economic and Social Commission for Asia and the Pacific (ESCAP) on promoting regional economic cooperation and integration, focuses on the China-Central Asia Corridor (China, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan), giving attention to the sub-region’s specific challenges, namely limited international transit opportunities and an increase in bandwidth requirements that is expected to grow exponentially, as the fourth industrial evolution centered on automation and artificial intelligence gathers momentum. The sub-region is characterized as highly dependent on the ease and costs of connecting to neighboring countries for transit, as many countries in the sub-region are landlocked developing countries (LLDC). Because of the geographical features and other factors, the development potential of Central Asia and its integration into globalization, continues to be stymied by insufficient international bandwidth and high transit costs to access international links. Therefore, improved ICT connectivity in Central Asia through the BRI corridor could result in improved availability and affordability of broadband networks and services in the sub-region.

For the purpose of this study, a gap analysis is the methodology that underpins the proposed topology for the China-Central Asia Corridor. The analysis included examining the current state of the optic infrastructure, such as existing and planned fiber-optic networks, existing Internet Exchange Points (IXPs) and international gateways. The study also identifies the key factors that determine the desired future state of infrastructure deployment for the BRI initiative. A topology that consists of connecting Almaty (Kazakhstan) and Urumqi (China), as core nodes, is proposed based on a partial mesh topology. Over and above this core finding, the study concludes that digital infrastructure connectivity has a tendency of lagging behind the rapid opportunities evolving, and the study therefore advocates for sub-regional and regional approaches, including the BRI and Asia-Pacific Information Superhighway (AP-IS) in further expanding regional broadband networks. A key recommendation of the study is co-deployment of broadband infrastructure along passive infrastructure, as an additional cost effective means of achieving fast and affordable broadband connectivity for all.

This study presents a comprehensive two-dimensional numerical analysis of natural laminar convection within a square cavity containing two circular heat sources, which simulate electric cables generating heat due to Joule heating. This scenario is particularly relevant in aeronautics, where excessive heating of electrical installations can lead to significant material and human safety risks. The primary objective of this research is to identify the optimal spacing between the two heat sources to mitigate the risk of overheating and ensure the safe operation of the electrical installation. To achieve this, various configurations were analyzed by adjusting the distance between the heat sources while also varying the Rayleigh number across a range from 10³ to 10⁶. The governing equations for the fluid flow and heat transfer were solved using a FORTRAN-based numerical code employing the finite volume method. The results indicate that the heat transfer characteristics within the cavity are significantly influenced by both the distance between the heat sources and the Rayleigh number. The analysis revealed that the average Nusselt number (Nu_avg) peaked at a value of 14.69 when the distance between the heat sources was set at 0.7 units and the Rayleigh number was at 10⁶. This finding suggests that maintaining this specific spacing between the electrical cables can optimize heat dissipation and enhance the safety of the installation. In conclusion, the study recommends adopting a spacing of 0.7 units between the electrical cables to ensure optimal thermal performance and minimize the risk of overheating, thereby safeguarding both the materials and personnel involved in aeronautical operations.