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There have been major advances in the science to predict the likely environmental concentrations of nanomaterials, which is a key component of exposure and subsequent risk assessment. Considerable progress has been since the first Material Flow Analyses (MFAs) in 2008, which were based on very limited information, to more refined current tools that take into account engineered nanoparticle (ENP) size distribution, form, dynamic release, and better-informed release factors. These MFAs provide input for all environmental fate models (EFMs), that generate estimates of particle flows and concentrations in various environmental compartments. While MFA models provide valuable information on the magnitude of ENP release, they do not account for fate processes, such as homo- and heteroaggregation, transformations, dissolution, or corona formation. EFMs account for these processes in differing degrees. EFMs can be divided into multimedia compartment models (e.g., atmosphere, waterbodies and their sediments, soils in various landuses), of which there are currently a handful with varying degrees of complexity and process representation, and spatially-resolved watershed models which focus on the water and sediment compartments. Multimedia models have particular applications for considering predicted environmental concentrations (PECs) in particular regions, or for developing generic "fate factors" (i.e., overall persistence in a given compartment) for life-cycle assessment. Watershed models can track transport and eventual fate of emissions into a flowing river, from multiple sources along the waterway course, providing spatially and temporally resolved PECs. Both types of EFMs can be run with either continuous sources of emissions and environmental conditions, or with dynamic emissions (e.g., temporally varying for example as a new nanomaterial is introduced to the market, or with seasonal applications), to better understand the situations that may lead to peak PECs that are more likely to result in exceedance of a toxicological threshold. In addition, bioaccumulation models have been developed to predict the internal concentrations that may accumulate in exposed organisms, based on the PECs from EFMs. The main challenge for MFA and EFMs is a full validation against observed data. To date there have been no field studies that can provide the kind of dataset(s) needed for a true validation of the PECs. While EFMs have been evaluated against a few observations in a small number of locations, with results that indicate they are in the right order of magnitude, there is a great need for field data. Another major challenge is the input data for the MFAs, which depend on market data to estimate the production of ENPs. The current information has major gaps and large uncertainties. There is also a lack of robust analytical techniques for quantifying ENP properties in complex matrices; machine learning may be able to fill this gap. Nevertheless, there has been major progress in the tools for generating PECs. With the emergence of nano- and microplastics as a leading environmental concern, some EFMs have been adapted to these materials. However, caution is needed, since most nano- and microplastics are not engineered, therefore their characteristics are difficult to generalize, and there are new fate and transport processes to consider.

The evolving dynamics of industrial convergence among the member countries of the Regional Comprehensive Economic Partnership (RCEP) framework have emerged as a significant subject that merits in-depth consideration and analysis. This study initially employs multi-regional input-output (MRIO) data and the social network analysis (SNA) method to delineate the levels and variation trends of this industrial convergence across the RCEP member countries. It then delves into the positive effects of this convergence phenomenon on the trade and investment fields of the member countries. The research findings indicate: (a) In 2006 and 2015, before the implementation of the RCEP, the RCEP member countries displayed a relatively close industrial convergence. The convergence levels exhibited a general upward trend on both the supply and the demand sides, but there were significant disparities in the levels of industrial convergence among the member countries. Furthermore, while the convergence in the three economic sectors showed an increasing trend, the development was uneven across the board. (b) Since the implementation of the RCEP, the trade ties among the member countries within the region have strengthened significantly, and the interplay between the countries' industrial and supply chains has been characterized by high-quality collaboration and demonstrated remarkable resilience. In addition, the convergence in the investment fields of the RCEP member countries and their respective industries has unleashed a wave of positive synergies. These findings offer valuable insights that can serve as a robust foundation for formulating effective policies to advance the growth and prosperity of the RCEP region. [ABSTRACT FROM AUTHOR]

The end of the Neoproterozoic global ice age has promoted the evolution of the Earth's surface system and initiated the 'Great Explosion of Life'. Glaciation deposits provide valuable insights into the extreme climate conditions. In the southern margin of the North China Craton (NCC), an Ediacaran glacial deposit named 'Luoquan Formation' has been recently described in Luonan County, Shaanxi Province. It has significant characteristics of dark grey and black glacial deposits. Through extensive research in sedimentology, geochemistry and geochronology, the glacial sedimentary evolution sequence of the Luoquan Formation has been established. This research also help to define the age of the formation and reveal its provenance and sedimentary environment. The study reveals that four lithofacies associations were identified in the Luoquan Formation: diamictites, carbonates, dropstone‐bearing rock and black shale. The Luoquan Formation has experienced three cycles of glacial advance–retreat. Sedimentological evidence suggests that the sedimentary environments of the Luoquan Formation evolved from subglacial (diamictite) to intertidal, then to intertidal lagoon, or from subglacial deposits to shoreface (inner shelf, subtidal), then to deep water basin and fine‐grained turbidite and ice‐rafting. The age of the Luoquan Formation is estimated to be 562–550 Ma constrained by indirect chronological and paleontological data, maybe representing an Upper Ediacaran glaciation that occurred later than the Gaskiers glaciation. The overall age profile of detrital zircons from the Luoquan Formation can be divided into six groups, ranging from 1.1 to 1.6, 1.85 to 1.95, ~2.1, ~2.3, ~2.5 and 2.65 to 2.9 Ga. These age groups are consistent with the Archean to Meso‐Neoproterozoic magmatic–tectonic events in the southern margin of NCC, indicating they are ascribed to an origination directly from the southern margin of NCC. The Luoquan Formation exhibits the characteristics of isochronous and different sedimentary facies, with the glacial front moving from north to south. The discovery of Luoquan Formation in Lianshuigou section not only reflects the important significance of the restoration and reconstruction of the Ediacaran ice age, paleoenvironment and palaeogeography of the NCC but also provides significant evidence to support the further subdivision and correlation within the Ediacaran glacial deposits globally. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are widely applied in various clinical disorders, including acute lung injury (ALI). We aimed to investigate the effects of human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs)-derived exosomal microRNA-22-3p (miR-22-3p) on lipopolysaccharid (LPS)-induced ALI via regulating frizzled class receptor 6 (FZD6). Rat lung cells were selected to construct the LPS-induced ALI cell model. The LPS-treated cells were transfected with restored miR-22-3p and depleted FZD6 for investigating their roles in ALI. Human UCB-MSCs were cultured and exosomes were extracted. Rat lung cells were co-cultured with exosomes that had been transfected with restored miR-22-3p and upregulated FZD6 to detect their roles in inflammatory reaction, oxidative stress, cell proliferation activity and apoptosis. The ALI rat model was established through LPS inhalation and the rats were respectively treated. Then, the pathology, apoptosis and expression of the NF-κB signaling pathway-related factors in rat lung tissues were determined. miR-22-3p expression was reduced and FZD6 expression was enhanced in LPS-treated rat lung cells while exosomes raised miR-22-3p expression and decreased FZD6 expression. In LPS-treated cells, up-regulating miR-22-3p or depleting FZD6 reduced inflammatory reaction and oxidative stress response, raised rat lung cell proliferation activity and inhibited cell apoptosis rate. In the in vivo ALI model, exosomes suppressed pathological changes, apoptosis and NF-κB expression in LPS-treated rats. Upregulated miR-22-3p further attenuated ALI. Our study highlights the potential of UCB-MSC-exosomal miR-22-3p in preventing ALI. This study may provide further insights into ALI therapy. [ABSTRACT FROM AUTHOR]