Effect of Strain Rate Sensitivity on Fracture of Laminated Rings under Dynamic Compressive Loading

The effects of cladding layers of rate-sensitive materials on the ductility and fracture strain of compressed rings are numerically investigated by using the finite element method (FEM) and employing the Johnson–Cook (J–C) model. The results show that ductility is governed by the behavior of the material that is located at the ring outer wall regardless of the volume fraction of the core and clad materials. However, as the number of layers increases, this influence becomes less noticeable. Moreover, as barreling increases at the outer wall and decreases at the inner wall, fracture strain increases. Furthermore, the effects of ring shape factor and bonding type of clad and core materials are numerically evaluated. The numerical results show that less force per unit volume is required to fracture narrower rings and that using a noise diffusion pattern at the interface of the materials is more suitable to simulate crack propagation in the compressed rings and functionally graded materials (FGMs). Additionally, delamination has a direct relation to layer thickness and can occur even in the presence of perfect bonding conditions owing to differences among the material and fracture parameters of laminated layers.

In planta dynamics, transport-biases and endogenous functions of mobile siRNAs in Arabidopsis

In RNA interference (RNAi), small-interfering (si)RNAs processed from double-stranded RNA guide ARGONAUTE(AGO) proteins to silence sequence-complementary RNA/DNA. Plant RNAi can propagate locally and systemically, but despite recent mechanistic advances, basic questions/hurdles remain unaddressed. For instance, RNAi is inferred to diffuse through plasmodesmata, yet how its dynamics in planta compares with that of established symplastic-diffusion markers remains unknown. Also unknown is why select siRNA species, or size-classes thereof, are recovered in RNAi-recipient tissues, yet only under some experimental settings. Finally, RNAi shootward movement in micro-grafted Arabidopsis -necessary to study its presumptive transgenerational effects- has not been achieved thus far and endogenous functions of mobile RNAi remain scarcely documented. Focusing on non-amplified RNAi in Arabidopsis, we show here that (i) transgenic RNAi-movement, although symplasmic, only partially recapitulates the diffusion pattern of free GFP in planta, (ii) the presence/absence of specific AGOs in incipient/traversed/recipient tissues likely explains the apparent siRNA-selectivity observed during vascular movement, (iii) stress application allows endo-siRNA translocation against the shoot-to-root phloem flow, and (iv) mobile endo-siRNAs generated from a single inverted-repeat(IR) locus, have the potential to regulate hundreds of transcripts. Our results close important knowledge-gaps, rationalize previously-noted inconsistencies between mobile RNAi settings, and provide a framework for functional endo-siRNA studies.

Modelling the Latent Semantics of Diffusion Sources in Information Cascade Prediction

Predicting the information spread tendency can help products recommendation and public opinion management. The existing information cascade prediction models are devoted to extract the chronological features from diffusion sequences but treat the diffusion sources as ordinary users. Diffusion source, the first user in the information cascade, can indicate the latent topic and diffusion pattern of an information item to mine user potential common interests, which facilitates information cascade prediction. In this paper, for modelling the abundant implicit semantics of diffusion sources in information cascade prediction, we propose a Diffusion Source latent Semantics-Fused cascade prediction framework, named DSSF. Specifically, we firstly apply diffusion sources embedding to model the special role of the source users. To learn the latent interaction between users and diffusion sources, we proposed a co-attention-based fusion gate which fuses the diffusion sources’ latent semantics with user embedding. To address the challenge that the distribution of diffusion sources is long-tailed, we develop an adversarial training framework to transfer the semantics knowledge from head to tail sources. Finally, we conduct experiments on real-world datasets, and the results show that modelling the diffusion sources can significantly improve the prediction performance. Besides, this improvement is limited for the cascades from tail sources, and the adversarial framework can help.

Collective patterns of social diffusion are shaped by individual inertia and trend-seeking

Social conventions change when individuals collectively adopt an alternative over the status quo, in a process known as social diffusion. Our repeated trials of a multi-round experiment provided data that helped motivate the proposal of an agent-based model of social diffusion that incorporates inertia and trend-seeking, two behavioural mechanisms that are well documented in the social psychology literature. The former causes people to stick with their current decision, the latter creates sensitivity to population-level changes. We show that such inclusion resolves the contradictions of existing models, allowing to reproduce patterns of social diffusion which are consistent with our data and existing empirical observations at both the individual and population level. The model reveals how the emergent population-level diffusion pattern is critically shaped by the two individual-level mechanisms; trend-seeking guarantees the diffusion is explosive after the diffusion process takes off, but inertia can greatly delay the time to take-off.

1116Spatial diffusion of the 2015-2016 Zika, dengue, and chikungunya epidemics in Rio de Janeiro, Brazil

Background Text: Different countries, especially Brazil, that have faced recurrent dengue epidemics for decades and chikungunya epidemics since 2014, have had to restructure their health services to combat a triple epidemic of arboviruses - Zika, dengue, and Chikungunya - transmitted by the same vector, mainly Aedes aegypti, in 2015-2016. Several efforts have been made to better understand these three arboviruses. The knowledge of the patterns of spatial diffusion of diseases during an epidemic can contribute to the planning of surveillance actions and control of these diseases. This study aimed to identify spatial diffusion processes of these viruses in the context of the triple epidemic in 2015-2016 in Rio de Janeiro, Brazil. Methods Text: Two study designs were used: cross-sectional and ecological. Zika, dengue, and chikungunya cases notified to the national notificable disease surveillance system of the Ministry of Health of Brazil in 2015 and 2016 were used. The residential addresses of the cases were geocoded. Sequential Kernel maps, nearest-neighbor ratios calculated cumulatively over time, Moran global autocorrelation correlograms, and local autocorrelation changes over time were used to identify spatial diffusion patterns. Results Text: Our findings suggest an expansion diffusion pattern for the 2015-2016 triple epidemic of Zika, dengue and chikungunya in the city of Rio de Janeiro, Brazil, as well as the sites most affected by the diseases. Conclusions Text: The spatial diffusion pattern of expansion was suggested by the results of the spatial analysis used. Key messages Text: These findings can be considered for more effective control measures and for new studies on the dynamics of these three arboviruses.

Neuroprotective Ability of Apocynin Loaded Nanoparticles (APO-NPs) as NADPH Oxidase (NOX)-Mediated ROS Modulator for Hydrogen Peroxide-Induced Oxidative Neuronal Injuries

Apocynin (APO) is a known multi-enzymatic complexed compound, employed as a viable NADPH oxidase (NOX) inhibitor, extensively used in both traditional and modern-day therapeutic strategies to combat neuronal disorders. However, its therapeutic efficacy is limited by lower solubility and lesser bioavailability; thus, a suitable nanocarrier system to overcome such limitations is needed. The present study is designed to fabricate APO-loaded polymeric nanoparticles (APO-NPs) to enhance its therapeutic efficacy and sustainability in the biological system. The optimized APO NPs in the study exhibited 103.6 ± 6.8 nm and −13.7 ± 0.43 mV of particle size and zeta potential, respectively, along with further confirmation by TEM. In addition, the antioxidant (AO) abilities quantified by DPPH and nitric oxide scavenging assays exhibited comparatively higher AO potential of APO-NPs than APO alone. An in-vitro release profile displayed a linear diffusion pattern of zero order kinetics for APO from the NPs, followed by its cytotoxicity evaluation on the PC12 cell line, which revealed minimal toxicity with higher cell viability, even after treatment with a stress inducer (H2O2). The stability of APO-NPs after six months showed minimal AO decline in comparison to APO only, indicating that the designed nano-formulation enhanced therapeutic efficacy for modulating NOX-mediated ROS generation.

Diffusion of sylvatic yellow fever in the state of São Paulo, Brazil

We investigated the sylvatic yellow fever (SYF) diffusion process in São Paulo (SP) between 2016 and 2019. We developed an ecological study of SYF through autochthonous human cases and epizootics of non-human primates (NHPs) that were spatiotemporally evaluated. We used kriging to obtain maps with isochrones representative of the evolution of the outbreak and characterized its diffusion pattern. We confirmed 648 human cases of SYF in SP, with 230 deaths and 843 NHP epizootics. Two outbreak waves were identified: one from West to East (2016 and 2017), and another from the Campinas region to the municipalities bordering Rio de Janeiro, Minas Gerais, and Paraná and those of the SP coast (2017–2019). The SYF outbreak diffusion process was by contagion. The disease did not exhibit jumps between municipalities, indicating that the mosquitoes and NHPs were responsible for transmitting the virus. There were not enough vaccines to meet the population at risk; hence, health authorities used information about the epizootic occurrence in NHPs in forest fragments to identify priority populations for vaccination.

Global Environment and Local Governments: Global Norms, Policy Adoption, and Local Diffusion

This article investigates a central question in modern organization theory, how organizations adapt to environmental changes by examining the diffusion of environmental ordinances among Korean local governments, 1995 to 2016. There are two waves in the diffusion; ‘Environment Basic Ordinance (1996-2007)’ and ‘Green Growth Ordinance (2010-2013).’ We argue that Korean local governments have increasingly become autonomous and accountable actors that respond to diversified stimulus from surrounding environments, while also concerning about their own needs and capacity. Hence, in adopting ‘Green Growth Ordinances,’ competitively adopted in the 2010s, Korean local governments considered more factors than they had done for ‘Environment Basic Ordinances.’ Employing event history analysis, we find empirical support for this argument. By comparing the diffusion pattern of the two environmental ordinances, this paper traces changing mechanisms of local environmental governance as well as policy diffusion among Korean local governments.

Neuroprotective ability of Apocynin Loaded Nanoparticles (APO-NPs) as NADPH Oxidase (NOX)-Mediated ROS Modulator for Hydrogen Peroxide-Induced Oxidative Neuronal Injuries

Apocynin (APO) is a known multi enzymatic complexed compound, employed as a viable NADPH oxidase (NOX) inhibitor, extensively used in both traditional and modern-day therapeutic strategies to combat neuronal disorders. However, its therapeutic efficacy is limited by its lower solubility and lesser bioavailability thus, a suitable nanocarrier system to overcome such limitations is needed. Present study is designed to fabricate APO loaded polymeric nanoparticles (APO-NPs) to enhance its therapeutic efficacy and sustainability in the biological system. The optimized APO NPs in the study exhibited 103.6 ± 6.8 nm and -13.7 ± 0.43 mV of particle size and zeta potential respectively along with further confirmation by TEM. Also, the antioxidant (AO) abilities quantified by DPPH and Nitric oxide scavenging assays exhibited comparatively higher AO potential of APO-NPs than APO alone. In-vitro release profile displayed a linear diffusion pattern of zero order kinetics for APO–NPs, followed by its cytotoxicity evaluation on PC12 cell line that revealed minimal toxicity with higher cell viability, even after treatment with stress inducer (H2O2). The stability of APO-NPs checked after six months showed minimal AO decline in comparison to APO only, indicating that designed nano formulation has enhanced therapeutic efficacy for modulating NOX mediated ROS generation.