A Large-area dc Grid Anode Glow Discharge in Helium

Plasma Physics Reports - A grid anode glow discharge is a promising source of plasma for absorbing electromagnetic radiation. This paper presents an experimental study of a large-area dc grid anode...     

Microalgae–bacteria symbiosis in microalgal growth and biofuel production: a review

Photosynthetic microalgae can capture solar energy and convert it to bioenergy and biochemical products. In nature or industrial processes, microalgae live together with bacterial communities and may maintain symbiotic relationships. In general interactions, microalgae exude dissolved organic carbon that becomes available to bacteria. In return, the bacteria remineralize sulphur, nitrogen and phosphorous to support the further growth of microalgae. In specific interactions, heterotrophic bacteria supply B vitamins as organic cofactors or produce siderophores to bind iron, which could be utilized by microalgae, while the algae supply fixed carbon to the bacteria in return. In this review, we focus on mutualistic relationship between microalgae and bacteria, summarizing recent studies on the mechanisms involved in microalgae–bacteria symbiosis. Symbiotic bacteria on promoting microalgal growth are described and the relevance of microalgae–bacteria interactions for biofuel production processes is discussed. Symbiotic microalgae–bacteria consortia could be utilized to improve microalgal biomass production and to enrich the biomass with valuable chemical and energy compounds. The suitable control of such biological interactions between microalgae and bacteria will help to improve the microalgae-based biomass and biofuel production in the future.     

Establishment of intestinal organoid cultures modeling injury-associated epithelial regeneration

The capacity of 3D organoids to mimic physiological tissue organization and functionality has provided an invaluable tool to model development and disease in vitro. However, conventional organoid cultures primarily represent the homeostasis of self-organizing stem cells and their derivatives. Here, we established a novel intestinal organoid culture system composed of 8 components, mainly including VPA, EPZ6438, LDN193189, and R-Spondin 1 conditioned medium, which mimics the gut epithelium regeneration that produces hyperplastic crypts following injury; therefore, these organoids were designated hyperplastic intestinal organoids (Hyper-organoids). Single-cell RNA sequencing identified different regenerative stem cell populations in our Hyper-organoids that shared molecular features with in vivo injury-responsive Lgr5⁺ stem cells or Clu⁺ revival stem cells. Further analysis revealed that VPA and EPZ6438 were indispensable for epigenome reprogramming and regeneration in Hyper-organoids, which functioned through epigenetically regulating YAP signaling. Furthermore, VPA and EPZ6438 synergistically promoted regenerative response in gut upon damage in vivo. In summary, our results demonstrated a new in vitro organoid model to study epithelial regeneration, highlighting the importance of epigenetic reprogramming that pioneers tissue repair.Subject terms: Intestinal stem cells, Regeneration     

Polyphyly and species delimitation of Picea brachytyla (Pinaceae) based on population genetic data

Accurate species delimitation is fundamental to biodiversity conservation. The endangered spruce Picea brachytyla (Franch.) E. Pritz. was suggested to be polyphyletic based on a limited number of samples in previous studies. To evaluate polyphyly of P. brachytyla, we sampled 139 individuals from 16 populations across most of its distributional range, plus representatives of two related species, Picea likiangensis (Franch.) E. Pritz. and Picea wilsonii Mast. We sequenced 13 nuclear loci and three chloroplast and two mitochondrial loci for the following species delimitation. Phylogenetic analyses of nuclear loci grouped all individuals of P. brachytyla from Sichuan and Chongqing into one distinct lineage and those from Yunnan and Tibet (southern distribution) nested within the P. likiangensis species complex. Structure analyses confirmed this result. Networks of chloroplast DNA haplotypes similarly showed that P. brachytyla from the southern distribution nested within the P. likiangensis species complex, whereas haplotypes for the northern distribution comprised a separate and well-supported lineage. These results suggest that P. brachytyla from the southern distribution is a part of the P. likiangensis species complex and should be removed from P. brachytyla. Our study highlights the utility of population genetic evidence in delimitating endangered species and understanding the conservation status of such species.     

Computational discovery of nanoporous materials for energy- and environment-related applications

ABSTRACT

Our society is currently facing critical energy and environment issues, due to the consistent increase in the usage of fossil fuels and anthropogenic activities. One of the viable solutions is to develop better materials to enable more energy-efficient processes for various applications, including gas separations, energy storage, desalination, etc. Nanoporous materials such as zeolites, metal–organic frameworks (MOFs), and nanoporous graphene have drawn considerable attention as promising candidates in these applications owing to many of their favourable properties. Moreover, the tunability of porous materials results in essentially infinitely large number of possible candidates. While such vast materials space provides great opportunities, it also imposes a significant challenge on the selection of promising candidates. To this end, computational methods, such as molecular simulations, can play an important role in facilitating the discovery and design of optimal materials. In this review, we introduce several computational studies conducted for large-scale materials screenings for gas separations and for the discovery of novel membranes for water filtrations. Furthermore, in light of the importance of molecular force fields for reliable computational predictions, we also discuss some recent developments in this field. Overall, this article discusses the recent advances of computational material discoveries and methodology developments.     

Transformative Network Modeling of Multi-omics Data Reveals Detailed Circuits,Key Regulators,and Potential Therapeutics for Alzheimer’s Disease

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