A Prebiotic Ribosylation of Pyrimidine Nucleobases Enabled by Metal Cations and Clay Minerals

We report a prebiotically relevant solution to the N1-ribosylation of pyrimidine nucleobases, a well-known challenge to the RNA world hypothesis. We found that the presence of metal cations and clay minerals enable the previously unachievable direct ribosylation of uracil. Spectroscopy and chromatography analyses confirmed the formation of ribosylated uracil. The method can be extended to the ribosylation of 2-pyrimidinone. These findings are also compatible with the metal-doped-clay model, developed by our lab for the unified route of the selection of ribose and subsequent syntheses of nucleotide and RNA.

Closing Connectivity Gap: An Overview of Mobile Coverage Solutions for Not-Spots in Rural Zones

Access to broadband communications in different parts of the world has become a priority for some governments and regulatory authorities around the world in recent years. Building new digital roads and pursuing a connected society includes looking for easier access to the internet. In general, not all areas where people congregate are fully covered, especially in rural zones, thus restricting access to data communications and inducing inequality. In the present review article, we have comprehensively surveyed the use of three platforms to deliver broadband services to such remote and low-income areas, and they are proposed as follows: unmanned aerial vehicles (UAV), altitude platforms (AP), and low-Earth orbit (LEO) satellites. These novel strategies support the connected and accessible world hypothesis. Hence, UAVs are considered a noteworthy solution since their efficient maneuverability can solve rural coverage issues or not-spots.

A Prebiotic Ribosylation of Pyrimidine Nucleobases Promoted by Metal Cations and Clay Minerals

We report a prebiotically relevant solution to the N1-ribosylation of pyrimidine nucleobases, a well-known challenge in the RNA World hypothesis. It is found that the presence of metal cations and clay mineral enables the previously unachievable direct ribosylation of uracil, providing by far the highest yield. Spectroscopy and chromatography analyses confirmed the formation of ribosylated uracil. The method can also be extended to the ribosylation of 2-pyrimidinone. These findings are also compatible with the metal-doped-clay model developed by our lab for the unified route of the selection of ribose and subsequent syntheses of nucleotide and RNA.

Gender differences in videoed accounts of victim blaming for revenge porn for self-taken and stealth-taken sexually explicit images and videos

Using video recounts from revenge porn victims, this study explores whether levels of victim blaming differs for the sharing of self- and stealth-taken sexually explicit images and videos. Building on previous work which has demonstrated victim blame for both self- and stealth generated images in occurrences of revenge porn (Zvi & Schechory-Bitton, 2020), the reported study presents an original and ecologically valid methodological approach whereby 342 (76 male, 266 female) participants (Mage = 39.27, SD = 11.70) from the UK watched videoed accounts of real experiences of falling victim to revenge porn, rather than using text based, often fictional, vignettes to attribute blame which dominate studies in this area. All data was collected in 2019. The results demonstrated that significantly more blame was assigned to victims when participants were indirectly rather than directly asked who was to blame for the occurrence of revenge porn, supporting the notion of an unconscious processing bias in attributing blame. More blame was also assigned to those victims who themselves generated the material compared to when it had been acquired without their awareness by a perpetrator, suggesting the cognitive bias to be in line with a just world hypothesis. Male participants were more likely to blame a victim than were female participants, although sex of victim and mode of shared sexually-explicit material (video or image) did not appear to affect levels of victim-blame. Findings are considered in terms of extant research and the need for future work in the area of victim blame and revenge pornography.

Closing Connectivity Gap: An Overview of Mobile Coverage Solutions for Not-Spots in Rural Zones

Access to broadband communications in different parts of the world has become a priority for some governments and regulatory authorities around the world in recent years. Building new digital roads and pursuing a connected society includes looking for easier access to the Internet. In general, not all the areas where people congregate are fully covered, especially in rural zones, thus restricting access to data communications and bringing inequality. In the present review article, we have comprehensively surveyed the use of three platforms to deliver broadband services to such remote and low-income areas are proposed: Unmanned Aerial Vehicles (UAV), Altitude Platforms (APS), and Low-Earth Orbit (LEO) satellites. These novel strategies support the connected and accessible world hypothesis. Hence UAVs are considered a noteworthy solution since their efficient maneuverability can aboard the rural coverage issues or not-spots.

The Nearer, the Better? The Impact of Cultural and Geographic Distance on Crowdfunding Project Attractiveness

Information asymmetry between backers and project creators impedes the crowdfunding success. Consequently, creators usually rely on various information to alleviate information asymmetry. Particularly, the location information of both backers and creators embodies their geographic and cultural distance, which may affect crowdfunding project attractiveness. Whereas current literature almost ignores the role cultural distance in crowdfunding, this research focuses on the reward-based crowdfunding, so that it becomes salient to form the appreciation and judgment of the innovative, creative, or artistic nature of projects. Meanwhile, geographic distance is examined to join the debates between flat world hypothesis and home bias proposition. A series of econometric models are examined based on a sample of 264 fundraising projects collected from Kitckstarter.com through Python program. Results show that cultural distance exerts a U-shape effect, which initially impedes the crowdfunding performance but promote projects when large enough. Geographic distance generally exerts insignificant impact on crowdfunding performance. Furthermore, cultural and geographic distance exerts the asymmetric effects on experienced versus new backers. This article underscores the important implications of cultural distance on reward-based crowdfunding. By showing the differential effects of cultural and geographic distance on experience versus new backers, it empirically infers the social capital as the underlying mechanism.

Colony-like Protocell Superstructures

We report the formation, growth, and dynamics of model protocell superstructures on solid surfaces, resembling single cell colonies. These structures, consisting of several layers of lipidic compartments enveloped in a dome-shaped outer lipid bilayer, emerged as a result of spontaneous shape transformation of lipid agglomerates deposited on thin film aluminum surfaces. Collective protocell structures were observed to be mechanically more stable compared to isolated spherical compartments. We show that the model colonies encapsulate DNA and accommodate non-enzymatic, strand displacement DNA reactions. The membrane envelope is able to disassemble and expose individual daughter protocells, which can migrate and attach via nano-tethers to distant surface locations, while maintaining their encapsulated contents. Some colonies feature ‘exo-compartments’, which spontaneously extend out of the enveloping bilayer, internalize DNA, and merge again with the superstructure. A continuum elastohydrodynamic theory that we developed reveals that the subcompartment formation must be governed by attractive van der Waals (vdW) interactions between the membrane and surface. The balance between membrane bending and vdW interactions yields a critical length scale of 273 nm, above which the membrane invaginations can form subcompartments. The findings support our hypotheses that in extension of the ‘lipid world hypothesis’, protocells may have existed in the form of colonies, potentially benefiting from the increased mechanical stability provided by a superstructure.

Protein world and hemochiralty

Protein world hypothesis and the origin of homochiralty are described. By using enzyme catalyzing itself, L-amino acid can replicate. L-amino acid also catalyze D-sugar production. By using Ramachandran plot, L-amino acid is favored for generating right alpha helix and beta sheet. Thus, homochiralty of earth happened.

Spontaneous formation of prebiotic compartment colonies on Hadean Earth and pre-Noachian Mars

The primitive cells that emerged at the origin of life are commonly viewed as spherical biosurfactant shells, freely suspended in aqueous media (1-3). This model explains initial, but not subsequent events in the development process towards structured protocells. Taking into consideration the involvement of naturally occurring surfaces, which were abundant on the early Earth (4), we report feasible and productive pathways for the development of primitive cells. Surfaces intrinsically possess energy, easily utilized by the interfacing amphiphiles, such as lipids, to attain self-organization and spontaneous transformations (5-7). We show that the physical interaction of phospholipid pools with 20 Hadean Earth analogue materials as well as a Martian meteorite composed of fused regolith representing the ancient crust of Mars, consistently lead to the shape transformation and autonomous formation of surfactant compartment assemblies. Dense, colony-like protocell populations grow from these lipid deposits, predominantly at the grain boundaries or cleavages of the investigated natural surfaces, and remain there for several days. The model protocells in our study are able to autonomously develop, transform and pseudo-divide, and encapsulate RNA as well as DNA. We also demonstrate that they can accommodate non-enzymatic, DNA strand displacement reactions. Our findings suggest a feasible route towards the transformation from non-living to living entities, and provide fresh support for the 'Lipid World' hypothesis (8).