A novel anaerobic consortium, named DehaloR^2, that performs rapid and complete reductive dechlorination of trichloroethene (TCE) to ethene is described. DehaloR^2 was developed from estuarine sediment from the Back River of the Chesapeake Bay and has been stably maintained in the laboratory for over 2 years. Initial sediment microcosms showed incomplete reduction of TCE to DCE with a ratio of trans- to cis- isomers of 1.67. However, complete reduction to ethene was achieved within 10 days after transfer of the consortium to sediment-free media and was accompanied by a shift to cis-DCE as the prevailing intermediate metabolite. The microbial community shifted from dominance of the Proteobacterial phylum in the sediment to Firmicutes and Chloroflexi in DehaloR^2, containing the genera Acetobacterium, Clostridium, and the dechlorinators Dehalococcoides. Also present were Spirochaetes, possible acetogens, and Geobacter which encompass previously described dechlorinators. Rates of TCE to ethene reductive dechlorination reached 2.83 mM Cl- d(-1) in batch bottles with a Dehalococcoides sp. density of 1.54E+11 gene copies per liter, comparing favorably to other enrichment cultures described in the literature and identifying DehaloR^2 as a promising consortium for use in bioremediation of chlorinated ethene-impacted environments.

Photochemical weathering leads to degradation of microplastics and releases chemical additives, polymeric fragments, and/or byproducts. This study evaluated the release kinetics of organotin compounds (OTCs) from three different sized (10–300 μm) polyvinyl chloride (PVC) microplastics under UV- and visible light irradiation. Four OTCs, dimethyltin (DMT), monomethyltin (MMT), dibutyltin (DBT), and monobutyltin (MBT), were found to release from PVC particles after 24 h leaching in darkness ranging from 2 to 20 μg·g-PVC–1. Under UV/visible light irradiation, only DMT and DBT were detectable, whereas MMT and MBT were not detected due to rapid photodegradation. The total tin concentrations (including organic and inorganic tins) in the aqueous phase monotonically increased under light exposure. By contrast, they reached plateaus after 24 h in darkness, confirming the photodegradation of OTCs. A release kinetics model was established and correctly interpreted the microplastics size effect on the OTC release process. Finally, the impacts of salinity and dissolved organic matter (DOM) were investigated. The release and photodegradation of OTCs were both inhibited at high salinity conditions, probably due to the enhanced readsorption of OTCs on PVC microplastics and the formation of halogen radicals that were less reactive toward neutral OTCs. The presence of DOM, however, increased OTCs release probably because the excited state triplet DOM (3DOM*) formed and reacted with OTCs from PVC microplastics.

Giant pandas consume different structural parts of bamboo (shoots, leaves and culms) during different seasons. Previous research showed different bamboo parts have varying nutritional content and that a long-term diet consisting of a single part of bamboo resulted in remarkable metabolic changes within captive giant pandas. However, the effects on the gut microbiome of giant pandas, as a result of a single bamboo part diet, have not been investigated. Here, we evaluated the changes in gut microbial communities based on single bamboo part diets and their potential implications by using 16S rRNA gene-based amplicon sequencing and metagenome shotgun sequencing. We found that the composition and function of the gut microbiome from captive giant pandas fed exclusively culms were significantly different from that of individuals fed shoots or leaves. During the culm feeding period, the gut microbiome showed strongest digestive capabilities for cellulose, hemicellulose and starch, and had the highest potential abilities for the biosynthesis of bile acids, fatty acids and amino acids. This suggests the microbiome aids in breaking down culm, which is more difficult for giant pandas to digest, as a means to compensate for the nutrient poor content of the culm. Genes related to fatty acid metabolism and tricarboxylic acid cycle enzymes were more abundant during the leaf stage diet than that in the shoot and culm stages. Thus, the microbiome may help giant pandas, which typically have low lipase levels, with fat digestion. These results illustrate that adaptive changes in the gut microbiome community and function may be an important mechanism to aid giant panda digestion when consuming different structural parts of bamboo.

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Global-change drivers that alter tidal amplitude or sea level could directly impact coastal aquifers' seawater-microbe interactions. The semidiurnal or diurnal tide can have consequences for chemical redistribution, because it deepens oxygen and nutrients penetration depth, thereby increasing O 2 depletion via microbial respiration in sediments during groundwater circulation. However, chemical and microbial distributions in tidal aquifers remain unclear, in deference to their link with depth and lateral location. By combining the microbes-accumulated equation with the traditional groundwater flow model in coastal aquifers, we explicitly unravelled the heterotrophic zonation, the salinity zonation, and the oxic zonation of tidal aquifers. According to the model estimates, salt penetrates deeper than reactive chemicals, and the heterotrophic high biomass zone is presumably 2-3 m deep. Such depth of heterotrophic distribution is 2-3 orders of magnitude higher than phototrophic distribution.Additionally, heterotrophic biomass can exhibit faint oscillations, even under the tide forces, whereas dissolved chemicals fluctuate significantly with tidal pumps. Due to

Our statistical analysis of research publications in the prestigious scientific journals Nature, Science and Cell reveals that papers represented by an image on the journal's cover gain many more citations in the academic literature than those papers in the same journals that are not represented on the cover. Meanwhile, the number of images used by high-prestige journals is much higher than that used by journals in general, which indicates both the emergence of a new aesthetic of prestige scientific publication, and also that this aesthetic is relevant to journals' impact. Furthermore, there are significant differences in the use of images in different countries and in different disciplines.

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